/* Loop Vectorization
- Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
Contributed by Dorit Naishlos <dorit@il.ibm.com>
This file is part of GCC.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA. */
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA. */
/* Loop Vectorization Pass.
To vectorize stmt S2, the vectorizer first finds the stmt that defines
the operand 'b' (S1), and gets the relevant vector def 'vb' from the
- vector stmt VS1 pointed by STMT_VINFO_VEC_STMT (stmt_info (S1)). The
+ vector stmt VS1 pointed to by STMT_VINFO_VEC_STMT (stmt_info (S1)). The
resulting sequence would be:
VS1: vb = px[i];
#include "system.h"
#include "coretypes.h"
#include "tm.h"
-#include "errors.h"
#include "ggc.h"
#include "tree.h"
#include "target.h"
-
#include "rtl.h"
#include "basic-block.h"
#include "diagnostic.h"
#include "cfglayout.h"
#include "expr.h"
#include "optabs.h"
+#include "params.h"
#include "toplev.h"
#include "tree-chrec.h"
#include "tree-data-ref.h"
#include "tree-scalar-evolution.h"
+#include "input.h"
#include "tree-vectorizer.h"
#include "tree-pass.h"
-
/*************************************************************************
Simple Loop Peeling Utilities
*************************************************************************/
-
-/* Entry point for peeling of simple loops.
- Peel the first/last iterations of a loop.
- It can be used outside of the vectorizer for loops that are simple enough
- (see function documentation). In the vectorizer it is used to peel the
- last few iterations when the loop bound is unknown or does not evenly
- divide by the vectorization factor, and to peel the first few iterations
- to force the alignment of data references in the loop. */
-struct loop *slpeel_tree_peel_loop_to_edge
- (struct loop *, struct loops *, edge, tree, tree, bool);
static struct loop *slpeel_tree_duplicate_loop_to_edge_cfg
(struct loop *, struct loops *, edge);
static void slpeel_update_phis_for_duplicate_loop
(struct loop *, struct loop *, bool after);
-static void slpeel_update_phi_nodes_for_guard (edge, struct loop *);
-static void slpeel_make_loop_iterate_ntimes (struct loop *, tree, tree, tree);
-static edge slpeel_add_loop_guard (basic_block, tree, basic_block);
-static void allocate_new_names (bitmap);
+static void slpeel_update_phi_nodes_for_guard1
+ (edge, struct loop *, bool, basic_block *, bitmap *);
+static void slpeel_update_phi_nodes_for_guard2
+ (edge, struct loop *, bool, basic_block *);
+static edge slpeel_add_loop_guard (basic_block, tree, basic_block, basic_block);
+
static void rename_use_op (use_operand_p);
-static void rename_def_op (def_operand_p, tree);
static void rename_variables_in_bb (basic_block);
-static void free_new_names (bitmap);
static void rename_variables_in_loop (struct loop *);
-
/*************************************************************************
- Vectorization Utilities.
+ General Vectorization Utilities
*************************************************************************/
+static void vect_set_dump_settings (void);
+
+/* vect_dump will be set to stderr or dump_file if exist. */
+FILE *vect_dump;
+
+/* vect_verbosity_level set to an invalid value
+ to mark that it's uninitialized. */
+enum verbosity_levels vect_verbosity_level = MAX_VERBOSITY_LEVEL;
+
+/* Number of loops, at the beginning of vectorization. */
+unsigned int vect_loops_num;
-/* Main analysis functions. */
-static loop_vec_info vect_analyze_loop (struct loop *);
-static loop_vec_info vect_analyze_loop_form (struct loop *);
-static bool vect_analyze_data_refs (loop_vec_info);
-static bool vect_mark_stmts_to_be_vectorized (loop_vec_info);
-static bool vect_analyze_scalar_cycles (loop_vec_info);
-static bool vect_analyze_data_ref_accesses (loop_vec_info);
-static bool vect_analyze_data_refs_alignment (loop_vec_info);
-static bool vect_compute_data_refs_alignment (loop_vec_info);
-static bool vect_analyze_operations (loop_vec_info);
-
-/* Main code transformation functions. */
-static void vect_transform_loop (loop_vec_info, struct loops *);
-static void vect_transform_loop_bound (loop_vec_info, tree niters);
-static bool vect_transform_stmt (tree, block_stmt_iterator *);
-static bool vectorizable_load (tree, block_stmt_iterator *, tree *);
-static bool vectorizable_store (tree, block_stmt_iterator *, tree *);
-static bool vectorizable_operation (tree, block_stmt_iterator *, tree *);
-static bool vectorizable_assignment (tree, block_stmt_iterator *, tree *);
-static enum dr_alignment_support vect_supportable_dr_alignment
- (struct data_reference *);
-static void vect_align_data_ref (tree);
-static void vect_enhance_data_refs_alignment (loop_vec_info);
-
-/* Utility functions for the analyses. */
-static bool vect_is_simple_use (tree , struct loop *, tree *);
-static bool exist_non_indexing_operands_for_use_p (tree, tree);
-static bool vect_is_simple_iv_evolution (unsigned, tree, tree *, tree *, bool);
-static void vect_mark_relevant (varray_type, tree);
-static bool vect_stmt_relevant_p (tree, loop_vec_info);
-static tree vect_get_loop_niters (struct loop *, tree *);
-static bool vect_compute_data_ref_alignment
- (struct data_reference *, loop_vec_info);
-static bool vect_analyze_data_ref_access (struct data_reference *);
-static bool vect_get_first_index (tree, tree *);
-static bool vect_can_force_dr_alignment_p (tree, unsigned int);
-static struct data_reference * vect_analyze_pointer_ref_access
- (tree, tree, bool);
-static bool vect_analyze_loop_with_symbolic_num_of_iters
- (tree niters, struct loop *loop);
-static tree vect_get_base_and_bit_offset
- (struct data_reference *, tree, tree, loop_vec_info, tree *, bool*);
-static struct data_reference * vect_analyze_pointer_ref_access
- (tree, tree, bool);
-static tree vect_compute_array_base_alignment (tree, tree, tree *, tree *);
-static tree vect_compute_array_ref_alignment
- (struct data_reference *, loop_vec_info, tree, tree *);
-static tree vect_get_ptr_offset (tree, tree, tree *);
-static tree vect_get_symbl_and_dr
- (tree, tree, bool, loop_vec_info, struct data_reference **);
-
-/* Utility functions for the code transformation. */
-static tree vect_create_destination_var (tree, tree);
-static tree vect_create_data_ref_ptr
- (tree, block_stmt_iterator *, tree, tree *, bool);
-static tree vect_create_index_for_vector_ref
- (struct loop *, block_stmt_iterator *);
-static tree vect_create_addr_base_for_vector_ref (tree, tree *, tree);
-static tree get_vectype_for_scalar_type (tree);
-static tree vect_get_new_vect_var (tree, enum vect_var_kind, const char *);
-static tree vect_get_vec_def_for_operand (tree, tree);
-static tree vect_init_vector (tree, tree);
-static tree vect_build_symbol_bound (tree, int, struct loop *);
-static void vect_finish_stmt_generation
- (tree stmt, tree vec_stmt, block_stmt_iterator *bsi);
-
-/* Utility function dealing with loop peeling (not peeling itself). */
-static void vect_generate_tmps_on_preheader
- (loop_vec_info, tree *, tree *, tree *);
-static tree vect_build_loop_niters (loop_vec_info);
-static void vect_update_ivs_after_vectorizer (struct loop *, tree);
-static tree vect_gen_niters_for_prolog_loop (loop_vec_info, tree);
-static void vect_update_niters_after_peeling (loop_vec_info, tree);
-static void vect_update_inits_of_dr
- (struct data_reference *, struct loop *, tree niters);
-static void vect_update_inits_of_drs (loop_vec_info, tree);
-static void vect_do_peeling_for_alignment (loop_vec_info, struct loops *);
-static void vect_transform_for_unknown_loop_bound
- (loop_vec_info, tree *, struct loops *);
-
-/* Utilities for creation and deletion of vec_info structs. */
-loop_vec_info new_loop_vec_info (struct loop *loop);
-void destroy_loop_vec_info (loop_vec_info);
-stmt_vec_info new_stmt_vec_info (tree stmt, struct loop *loop);
-
-static bool vect_debug_stats (struct loop *loop);
-static bool vect_debug_details (struct loop *loop);
+/* Loop location. */
+static LOC vect_loop_location;
+/* Bitmap of virtual variables to be renamed. */
+bitmap vect_vnames_to_rename;
\f
/*************************************************************************
Simple Loop Peeling Utilities
*************************************************************************/
-/* For each definition in DEFINITIONS this function allocates
- new ssa name. */
-
-static void
-allocate_new_names (bitmap definitions)
-{
- unsigned ver;
- bitmap_iterator bi;
-
- EXECUTE_IF_SET_IN_BITMAP (definitions, 0, ver, bi)
- {
- tree def = ssa_name (ver);
- tree *new_name_ptr = xmalloc (sizeof (tree));
-
- bool abnormal = SSA_NAME_OCCURS_IN_ABNORMAL_PHI (def);
-
- *new_name_ptr = duplicate_ssa_name (def, SSA_NAME_DEF_STMT (def));
- SSA_NAME_OCCURS_IN_ABNORMAL_PHI (*new_name_ptr) = abnormal;
-
- SSA_NAME_AUX (def) = new_name_ptr;
- }
-}
-
-
/* Renames the use *OP_P. */
static void
rename_use_op (use_operand_p op_p)
{
- tree *new_name_ptr;
+ tree new_name;
if (TREE_CODE (USE_FROM_PTR (op_p)) != SSA_NAME)
return;
- new_name_ptr = SSA_NAME_AUX (USE_FROM_PTR (op_p));
-
- /* Something defined outside of the loop. */
- if (!new_name_ptr)
- return;
-
- /* An ordinary ssa name defined in the loop. */
-
- SET_USE (op_p, *new_name_ptr);
-}
-
-
-/* Renames the def *OP_P in statement STMT. */
-
-static void
-rename_def_op (def_operand_p op_p, tree stmt)
-{
- tree *new_name_ptr;
-
- if (TREE_CODE (DEF_FROM_PTR (op_p)) != SSA_NAME)
- return;
-
- new_name_ptr = SSA_NAME_AUX (DEF_FROM_PTR (op_p));
+ new_name = get_current_def (USE_FROM_PTR (op_p));
/* Something defined outside of the loop. */
- if (!new_name_ptr)
+ if (!new_name)
return;
/* An ordinary ssa name defined in the loop. */
- SET_DEF (op_p, *new_name_ptr);
- SSA_NAME_DEF_STMT (DEF_FROM_PTR (op_p)) = stmt;
+ SET_USE (op_p, new_name);
}
tree phi;
block_stmt_iterator bsi;
tree stmt;
- stmt_ann_t ann;
- use_optype uses;
- vuse_optype vuses;
- def_optype defs;
- v_may_def_optype v_may_defs;
- v_must_def_optype v_must_defs;
- unsigned i;
+ use_operand_p use_p;
+ ssa_op_iter iter;
edge e;
edge_iterator ei;
-
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- rename_def_op (PHI_RESULT_PTR (phi), phi);
+ struct loop *loop = bb->loop_father;
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
{
stmt = bsi_stmt (bsi);
- get_stmt_operands (stmt);
- ann = stmt_ann (stmt);
-
- uses = USE_OPS (ann);
- for (i = 0; i < NUM_USES (uses); i++)
- rename_use_op (USE_OP_PTR (uses, i));
-
- defs = DEF_OPS (ann);
- for (i = 0; i < NUM_DEFS (defs); i++)
- rename_def_op (DEF_OP_PTR (defs, i), stmt);
-
- vuses = VUSE_OPS (ann);
- for (i = 0; i < NUM_VUSES (vuses); i++)
- rename_use_op (VUSE_OP_PTR (vuses, i));
-
- v_may_defs = V_MAY_DEF_OPS (ann);
- for (i = 0; i < NUM_V_MAY_DEFS (v_may_defs); i++)
- {
- rename_use_op (V_MAY_DEF_OP_PTR (v_may_defs, i));
- rename_def_op (V_MAY_DEF_RESULT_PTR (v_may_defs, i), stmt);
- }
-
- v_must_defs = V_MUST_DEF_OPS (ann);
- for (i = 0; i < NUM_V_MUST_DEFS (v_must_defs); i++)
- {
- rename_use_op (V_MUST_DEF_KILL_PTR (v_must_defs, i));
- rename_def_op (V_MUST_DEF_RESULT_PTR (v_must_defs, i), stmt);
- }
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter,
+ (SSA_OP_ALL_USES | SSA_OP_ALL_KILLS))
+ rename_use_op (use_p);
}
FOR_EACH_EDGE (e, ei, bb->succs)
- for (phi = phi_nodes (e->dest); phi; phi = PHI_CHAIN (phi))
- rename_use_op (PHI_ARG_DEF_PTR_FROM_EDGE (phi, e));
-}
-
-
-/* Releases the structures holding the new ssa names. */
-
-static void
-free_new_names (bitmap definitions)
-{
- unsigned ver;
- bitmap_iterator bi;
-
- EXECUTE_IF_SET_IN_BITMAP (definitions, 0, ver, bi)
{
- tree def = ssa_name (ver);
-
- if (SSA_NAME_AUX (def))
- {
- free (SSA_NAME_AUX (def));
- SSA_NAME_AUX (def) = NULL;
- }
+ if (!flow_bb_inside_loop_p (loop, e->dest))
+ continue;
+ for (phi = phi_nodes (e->dest); phi; phi = PHI_CHAIN (phi))
+ rename_use_op (PHI_ARG_DEF_PTR_FROM_EDGE (phi, e));
}
}
}
-/* This function copies phis from LOOP header to
- NEW_LOOP header. AFTER is as
- in update_phis_for_duplicate_loop function. */
-
-static void
-copy_phi_nodes (struct loop *loop, struct loop *new_loop,
- bool after)
-{
- tree phi, new_phi, def;
- edge new_e;
- edge e = (after ? loop_latch_edge (loop) : loop_preheader_edge (loop));
-
- /* Second add arguments to newly created phi nodes. */
- for (phi = phi_nodes (loop->header),
- new_phi = phi_nodes (new_loop->header);
- phi;
- phi = PHI_CHAIN (phi),
- new_phi = PHI_CHAIN (new_phi))
- {
- new_e = loop_preheader_edge (new_loop);
- def = PHI_ARG_DEF_FROM_EDGE (phi, e);
- add_phi_arg (&new_phi, def, new_e);
- }
-}
-
+/* Update the PHI nodes of NEW_LOOP.
-/* Update the PHI nodes of the NEW_LOOP. AFTER is true if the NEW_LOOP
- executes after LOOP, and false if it executes before it. */
+ NEW_LOOP is a duplicate of ORIG_LOOP.
+ AFTER indicates whether NEW_LOOP executes before or after ORIG_LOOP:
+ AFTER is true if NEW_LOOP executes after ORIG_LOOP, and false if it
+ executes before it. */
static void
-slpeel_update_phis_for_duplicate_loop (struct loop *loop,
+slpeel_update_phis_for_duplicate_loop (struct loop *orig_loop,
struct loop *new_loop, bool after)
{
- edge old_latch;
- tree *new_name_ptr, new_ssa_name;
- tree phi_new, phi_old, def;
- edge orig_entry_e = loop_preheader_edge (loop);
+ tree new_ssa_name;
+ tree phi_new, phi_orig;
+ tree def;
+ edge orig_loop_latch = loop_latch_edge (orig_loop);
+ edge orig_entry_e = loop_preheader_edge (orig_loop);
+ edge new_loop_exit_e = new_loop->single_exit;
+ edge new_loop_entry_e = loop_preheader_edge (new_loop);
+ edge entry_arg_e = (after ? orig_loop_latch : orig_entry_e);
+
+ /*
+ step 1. For each loop-header-phi:
+ Add the first phi argument for the phi in NEW_LOOP
+ (the one associated with the entry of NEW_LOOP)
+
+ step 2. For each loop-header-phi:
+ Add the second phi argument for the phi in NEW_LOOP
+ (the one associated with the latch of NEW_LOOP)
+
+ step 3. Update the phis in the successor block of NEW_LOOP.
+
+ case 1: NEW_LOOP was placed before ORIG_LOOP:
+ The successor block of NEW_LOOP is the header of ORIG_LOOP.
+ Updating the phis in the successor block can therefore be done
+ along with the scanning of the loop header phis, because the
+ header blocks of ORIG_LOOP and NEW_LOOP have exactly the same
+ phi nodes, organized in the same order.
+
+ case 2: NEW_LOOP was placed after ORIG_LOOP:
+ The successor block of NEW_LOOP is the original exit block of
+ ORIG_LOOP - the phis to be updated are the loop-closed-ssa phis.
+ We postpone updating these phis to a later stage (when
+ loop guards are added).
+ */
- /* Copy phis from loop->header to new_loop->header. */
- copy_phi_nodes (loop, new_loop, after);
- old_latch = loop_latch_edge (loop);
+ /* Scan the phis in the headers of the old and new loops
+ (they are organized in exactly the same order). */
- /* Update PHI args for the new loop latch edge, and
- the old loop preheader edge, we know that the PHI nodes
- are ordered appropriately in copy_phi_nodes. */
for (phi_new = phi_nodes (new_loop->header),
- phi_old = phi_nodes (loop->header);
- phi_new && phi_old;
- phi_new = PHI_CHAIN (phi_new), phi_old = PHI_CHAIN (phi_old))
+ phi_orig = phi_nodes (orig_loop->header);
+ phi_new && phi_orig;
+ phi_new = PHI_CHAIN (phi_new), phi_orig = PHI_CHAIN (phi_orig))
{
- def = PHI_ARG_DEF_FROM_EDGE (phi_old, old_latch);
+ /* step 1. */
+ def = PHI_ARG_DEF_FROM_EDGE (phi_orig, entry_arg_e);
+ add_phi_arg (phi_new, def, new_loop_entry_e);
+ /* step 2. */
+ def = PHI_ARG_DEF_FROM_EDGE (phi_orig, orig_loop_latch);
if (TREE_CODE (def) != SSA_NAME)
- continue;
-
- new_name_ptr = SSA_NAME_AUX (def);
+ continue;
- /* Something defined outside of the loop. */
- if (!new_name_ptr)
- continue;
+ new_ssa_name = get_current_def (def);
+ if (!new_ssa_name)
+ {
+ /* This only happens if there are no definitions
+ inside the loop. use the phi_result in this case. */
+ new_ssa_name = PHI_RESULT (phi_new);
+ }
/* An ordinary ssa name defined in the loop. */
- new_ssa_name = *new_name_ptr;
-
- add_phi_arg (&phi_new, new_ssa_name, loop_latch_edge(new_loop));
+ add_phi_arg (phi_new, new_ssa_name, loop_latch_edge (new_loop));
- /* Update PHI args for the original loop pre-header edge. */
- if (! after)
- SET_USE (PHI_ARG_DEF_PTR_FROM_EDGE (phi_old, orig_entry_e),
- new_ssa_name);
+ /* step 3 (case 1). */
+ if (!after)
+ {
+ gcc_assert (new_loop_exit_e == orig_entry_e);
+ SET_PHI_ARG_DEF (phi_orig,
+ new_loop_exit_e->dest_idx,
+ new_ssa_name);
+ }
}
}
/* Update PHI nodes for a guard of the LOOP.
- LOOP is supposed to have a preheader bb at which a guard condition is
- located. The true edge of this condition skips the LOOP and ends
- at the destination of the (unique) LOOP exit. The loop exit bb is supposed
- to be an empty bb (created by this transformation) with one successor.
+ Input:
+ - LOOP, GUARD_EDGE: LOOP is a loop for which we added guard code that
+ controls whether LOOP is to be executed. GUARD_EDGE is the edge that
+ originates from the guard-bb, skips LOOP and reaches the (unique) exit
+ bb of LOOP. This loop-exit-bb is an empty bb with one successor.
+ We denote this bb NEW_MERGE_BB because before the guard code was added
+ it had a single predecessor (the LOOP header), and now it became a merge
+ point of two paths - the path that ends with the LOOP exit-edge, and
+ the path that ends with GUARD_EDGE.
+ - NEW_EXIT_BB: New basic block that is added by this function between LOOP
+ and NEW_MERGE_BB. It is used to place loop-closed-ssa-form exit-phis.
+
+ ===> The CFG before the guard-code was added:
+ LOOP_header_bb:
+ loop_body
+ if (exit_loop) goto update_bb
+ else goto LOOP_header_bb
+ update_bb:
+
+ ==> The CFG after the guard-code was added:
+ guard_bb:
+ if (LOOP_guard_condition) goto new_merge_bb
+ else goto LOOP_header_bb
+ LOOP_header_bb:
+ loop_body
+ if (exit_loop_condition) goto new_merge_bb
+ else goto LOOP_header_bb
+ new_merge_bb:
+ goto update_bb
+ update_bb:
+
+ ==> The CFG after this function:
+ guard_bb:
+ if (LOOP_guard_condition) goto new_merge_bb
+ else goto LOOP_header_bb
+ LOOP_header_bb:
+ loop_body
+ if (exit_loop_condition) goto new_exit_bb
+ else goto LOOP_header_bb
+ new_exit_bb:
+ new_merge_bb:
+ goto update_bb
+ update_bb:
+
+ This function:
+ 1. creates and updates the relevant phi nodes to account for the new
+ incoming edge (GUARD_EDGE) into NEW_MERGE_BB. This involves:
+ 1.1. Create phi nodes at NEW_MERGE_BB.
+ 1.2. Update the phi nodes at the successor of NEW_MERGE_BB (denoted
+ UPDATE_BB). UPDATE_BB was the exit-bb of LOOP before NEW_MERGE_BB
+ 2. preserves loop-closed-ssa-form by creating the required phi nodes
+ at the exit of LOOP (i.e, in NEW_EXIT_BB).
+
+ There are two flavors to this function:
+
+ slpeel_update_phi_nodes_for_guard1:
+ Here the guard controls whether we enter or skip LOOP, where LOOP is a
+ prolog_loop (loop1 below), and the new phis created in NEW_MERGE_BB are
+ for variables that have phis in the loop header.
+
+ slpeel_update_phi_nodes_for_guard2:
+ Here the guard controls whether we enter or skip LOOP, where LOOP is an
+ epilog_loop (loop2 below), and the new phis created in NEW_MERGE_BB are
+ for variables that have phis in the loop exit.
+
+ I.E., the overall structure is:
+
+ loop1_preheader_bb:
+ guard1 (goto loop1/merg1_bb)
+ loop1
+ loop1_exit_bb:
+ guard2 (goto merge1_bb/merge2_bb)
+ merge1_bb
+ loop2
+ loop2_exit_bb
+ merge2_bb
+ next_bb
+
+ slpeel_update_phi_nodes_for_guard1 takes care of creating phis in
+ loop1_exit_bb and merge1_bb. These are entry phis (phis for the vars
+ that have phis in loop1->header).
+
+ slpeel_update_phi_nodes_for_guard2 takes care of creating phis in
+ loop2_exit_bb and merge2_bb. These are exit phis (phis for the vars
+ that have phis in next_bb). It also adds some of these phis to
+ loop1_exit_bb.
+
+ slpeel_update_phi_nodes_for_guard1 is always called before
+ slpeel_update_phi_nodes_for_guard2. They are both needed in order
+ to create correct data-flow and loop-closed-ssa-form.
+
+ Generally slpeel_update_phi_nodes_for_guard1 creates phis for variables
+ that change between iterations of a loop (and therefore have a phi-node
+ at the loop entry), whereas slpeel_update_phi_nodes_for_guard2 creates
+ phis for variables that are used out of the loop (and therefore have
+ loop-closed exit phis). Some variables may be both updated between
+ iterations and used after the loop. This is why in loop1_exit_bb we
+ may need both entry_phis (created by slpeel_update_phi_nodes_for_guard1)
+ and exit phis (created by slpeel_update_phi_nodes_for_guard2).
+
+ - IS_NEW_LOOP: if IS_NEW_LOOP is true, then LOOP is a newly created copy of
+ an original loop. i.e., we have:
+
+ orig_loop
+ guard_bb (goto LOOP/new_merge)
+ new_loop <-- LOOP
+ new_exit
+ new_merge
+ next_bb
+
+ If IS_NEW_LOOP is false, then LOOP is an original loop, in which case we
+ have:
+
+ new_loop
+ guard_bb (goto LOOP/new_merge)
+ orig_loop <-- LOOP
+ new_exit
+ new_merge
+ next_bb
+
+ The SSA names defined in the original loop have a current
+ reaching definition that that records the corresponding new
+ ssa-name used in the new duplicated loop copy.
+ */
+
+/* Function slpeel_update_phi_nodes_for_guard1
+
+ Input:
+ - GUARD_EDGE, LOOP, IS_NEW_LOOP, NEW_EXIT_BB - as explained above.
+ - DEFS - a bitmap of ssa names to mark new names for which we recorded
+ information.
+
+ In the context of the overall structure, we have:
+
+ loop1_preheader_bb:
+ guard1 (goto loop1/merg1_bb)
+LOOP-> loop1
+ loop1_exit_bb:
+ guard2 (goto merge1_bb/merge2_bb)
+ merge1_bb
+ loop2
+ loop2_exit_bb
+ merge2_bb
+ next_bb
+
+ For each name updated between loop iterations (i.e - for each name that has
+ an entry (loop-header) phi in LOOP) we create a new phi in:
+ 1. merge1_bb (to account for the edge from guard1)
+ 2. loop1_exit_bb (an exit-phi to keep LOOP in loop-closed form)
+*/
- This function creates phi nodes at the LOOP exit bb. These phis need to be
- created as a result of adding true edge coming from guard.
+static void
+slpeel_update_phi_nodes_for_guard1 (edge guard_edge, struct loop *loop,
+ bool is_new_loop, basic_block *new_exit_bb,
+ bitmap *defs)
+{
+ tree orig_phi, new_phi;
+ tree update_phi, update_phi2;
+ tree guard_arg, loop_arg;
+ basic_block new_merge_bb = guard_edge->dest;
+ edge e = EDGE_SUCC (new_merge_bb, 0);
+ basic_block update_bb = e->dest;
+ basic_block orig_bb = loop->header;
+ edge new_exit_e;
+ tree current_new_name;
+ tree name;
+
+ /* Create new bb between loop and new_merge_bb. */
+ *new_exit_bb = split_edge (loop->single_exit);
+ add_bb_to_loop (*new_exit_bb, loop->outer);
+
+ new_exit_e = EDGE_SUCC (*new_exit_bb, 0);
+
+ for (orig_phi = phi_nodes (orig_bb), update_phi = phi_nodes (update_bb);
+ orig_phi && update_phi;
+ orig_phi = PHI_CHAIN (orig_phi), update_phi = PHI_CHAIN (update_phi))
+ {
+ /* Virtual phi; Mark it for renaming. We actually want to call
+ mar_sym_for_renaming, but since all ssa renaming datastructures
+ are going to be freed before we get to call ssa_upate, we just
+ record this name for now in a bitmap, and will mark it for
+ renaming later. */
+ name = PHI_RESULT (orig_phi);
+ if (!is_gimple_reg (SSA_NAME_VAR (name)))
+ bitmap_set_bit (vect_vnames_to_rename, SSA_NAME_VERSION (name));
+
+ /** 1. Handle new-merge-point phis **/
+
+ /* 1.1. Generate new phi node in NEW_MERGE_BB: */
+ new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)),
+ new_merge_bb);
+
+ /* 1.2. NEW_MERGE_BB has two incoming edges: GUARD_EDGE and the exit-edge
+ of LOOP. Set the two phi args in NEW_PHI for these edges: */
+ loop_arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, EDGE_SUCC (loop->latch, 0));
+ guard_arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, loop_preheader_edge (loop));
+
+ add_phi_arg (new_phi, loop_arg, new_exit_e);
+ add_phi_arg (new_phi, guard_arg, guard_edge);
+
+ /* 1.3. Update phi in successor block. */
+ gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi, e) == loop_arg
+ || PHI_ARG_DEF_FROM_EDGE (update_phi, e) == guard_arg);
+ SET_PHI_ARG_DEF (update_phi, e->dest_idx, PHI_RESULT (new_phi));
+ update_phi2 = new_phi;
+
+
+ /** 2. Handle loop-closed-ssa-form phis **/
+
+ /* 2.1. Generate new phi node in NEW_EXIT_BB: */
+ new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)),
+ *new_exit_bb);
+
+ /* 2.2. NEW_EXIT_BB has one incoming edge: the exit-edge of the loop. */
+ add_phi_arg (new_phi, loop_arg, loop->single_exit);
+
+ /* 2.3. Update phi in successor of NEW_EXIT_BB: */
+ gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi2, new_exit_e) == loop_arg);
+ SET_PHI_ARG_DEF (update_phi2, new_exit_e->dest_idx, PHI_RESULT (new_phi));
+
+ /* 2.4. Record the newly created name with set_current_def.
+ We want to find a name such that
+ name = get_current_def (orig_loop_name)
+ and to set its current definition as follows:
+ set_current_def (name, new_phi_name)
+
+ If LOOP is a new loop then loop_arg is already the name we're
+ looking for. If LOOP is the original loop, then loop_arg is
+ the orig_loop_name and the relevant name is recorded in its
+ current reaching definition. */
+ if (is_new_loop)
+ current_new_name = loop_arg;
+ else
+ {
+ current_new_name = get_current_def (loop_arg);
+ /* current_def is not available only if the variable does not
+ change inside the loop, in which case we also don't care
+ about recording a current_def for it because we won't be
+ trying to create loop-exit-phis for it. */
+ if (!current_new_name)
+ continue;
+ }
+ gcc_assert (get_current_def (current_new_name) == NULL_TREE);
- FORNOW: Only phis which have corresponding phi nodes at the header of the
- LOOP are created. Here we use the assumption that after the LOOP there
- are no uses of defs generated in LOOP.
+ set_current_def (current_new_name, PHI_RESULT (new_phi));
+ bitmap_set_bit (*defs, SSA_NAME_VERSION (current_new_name));
+ }
- After the phis creation, the function updates the values of phi nodes at
- the LOOP exit successor bb:
+ set_phi_nodes (new_merge_bb, phi_reverse (phi_nodes (new_merge_bb)));
+}
- Original loop:
- bb0: loop preheader
- goto bb1
- bb1: loop header
- if (exit_cond) goto bb3 else goto bb2
- bb2: loop latch
- goto bb1
- bb3:
+/* Function slpeel_update_phi_nodes_for_guard2
+ Input:
+ - GUARD_EDGE, LOOP, IS_NEW_LOOP, NEW_EXIT_BB - as explained above.
+
+ In the context of the overall structure, we have:
+
+ loop1_preheader_bb:
+ guard1 (goto loop1/merg1_bb)
+ loop1
+ loop1_exit_bb:
+ guard2 (goto merge1_bb/merge2_bb)
+ merge1_bb
+LOOP-> loop2
+ loop2_exit_bb
+ merge2_bb
+ next_bb
+
+ For each name used out side the loop (i.e - for each name that has an exit
+ phi in next_bb) we create a new phi in:
+ 1. merge2_bb (to account for the edge from guard_bb)
+ 2. loop2_exit_bb (an exit-phi to keep LOOP in loop-closed form)
+ 3. guard2 bb (an exit phi to keep the preceding loop in loop-closed form),
+ if needed (if it wasn't handled by slpeel_update_phis_nodes_for_phi1).
+*/
- After guard creation (the loop before this function):
+static void
+slpeel_update_phi_nodes_for_guard2 (edge guard_edge, struct loop *loop,
+ bool is_new_loop, basic_block *new_exit_bb)
+{
+ tree orig_phi, new_phi;
+ tree update_phi, update_phi2;
+ tree guard_arg, loop_arg;
+ basic_block new_merge_bb = guard_edge->dest;
+ edge e = EDGE_SUCC (new_merge_bb, 0);
+ basic_block update_bb = e->dest;
+ edge new_exit_e;
+ tree orig_def, orig_def_new_name;
+ tree new_name, new_name2;
+ tree arg;
+
+ /* Create new bb between loop and new_merge_bb. */
+ *new_exit_bb = split_edge (loop->single_exit);
+ add_bb_to_loop (*new_exit_bb, loop->outer);
+
+ new_exit_e = EDGE_SUCC (*new_exit_bb, 0);
+
+ for (update_phi = phi_nodes (update_bb); update_phi;
+ update_phi = PHI_CHAIN (update_phi))
+ {
+ orig_phi = update_phi;
+ orig_def = PHI_ARG_DEF_FROM_EDGE (orig_phi, e);
+ /* This loop-closed-phi actually doesn't represent a use
+ out of the loop - the phi arg is a constant. */
+ if (TREE_CODE (orig_def) != SSA_NAME)
+ continue;
+ orig_def_new_name = get_current_def (orig_def);
+ arg = NULL_TREE;
- bb0: loop preheader
- if (guard_condition) goto bb4 else goto bb1
- bb1: loop header
- if (exit_cond) goto bb4 else goto bb2
- bb2: loop latch
- goto bb1
- bb4: loop exit
- (new empty bb)
- goto bb3
- bb3:
+ /** 1. Handle new-merge-point phis **/
- This function updates the phi nodes in bb4 and in bb3, to account for the
- new edge from bb0 to bb4. */
+ /* 1.1. Generate new phi node in NEW_MERGE_BB: */
+ new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)),
+ new_merge_bb);
-static void
-slpeel_update_phi_nodes_for_guard (edge guard_true_edge, struct loop * loop)
-{
- tree phi, phi1;
- basic_block bb = loop->exit_edges[0]->dest;
-
- for (phi = phi_nodes (loop->header); phi; phi = PHI_CHAIN (phi))
- {
- tree new_phi;
- tree phi_arg;
-
- /* Generate new phi node. */
- new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (phi)), bb);
-
- /* Add argument coming from guard true edge. */
- phi_arg = PHI_ARG_DEF_FROM_EDGE (phi, loop->entry_edges[0]);
- add_phi_arg (&new_phi, phi_arg, guard_true_edge);
-
- /* Add argument coming from loop exit edge. */
- phi_arg = PHI_ARG_DEF_FROM_EDGE (phi, EDGE_SUCC (loop->latch, 0));
- add_phi_arg (&new_phi, phi_arg, loop->exit_edges[0]);
-
- /* Update all phi nodes at the loop exit successor. */
- for (phi1 = phi_nodes (EDGE_SUCC (bb, 0)->dest);
- phi1;
- phi1 = PHI_CHAIN (phi1))
- {
- tree old_arg = PHI_ARG_DEF_FROM_EDGE (phi1, EDGE_SUCC (bb, 0));
- if (old_arg == phi_arg)
- {
- edge e = EDGE_SUCC (bb, 0);
-
- SET_PHI_ARG_DEF (phi1,
- phi_arg_from_edge (phi1, e),
- PHI_RESULT (new_phi));
- }
- }
- }
-
- set_phi_nodes (bb, phi_reverse (phi_nodes (bb)));
+ /* 1.2. NEW_MERGE_BB has two incoming edges: GUARD_EDGE and the exit-edge
+ of LOOP. Set the two PHI args in NEW_PHI for these edges: */
+ new_name = orig_def;
+ new_name2 = NULL_TREE;
+ if (orig_def_new_name)
+ {
+ new_name = orig_def_new_name;
+ /* Some variables have both loop-entry-phis and loop-exit-phis.
+ Such variables were given yet newer names by phis placed in
+ guard_bb by slpeel_update_phi_nodes_for_guard1. I.e:
+ new_name2 = get_current_def (get_current_def (orig_name)). */
+ new_name2 = get_current_def (new_name);
+ }
+
+ if (is_new_loop)
+ {
+ guard_arg = orig_def;
+ loop_arg = new_name;
+ }
+ else
+ {
+ guard_arg = new_name;
+ loop_arg = orig_def;
+ }
+ if (new_name2)
+ guard_arg = new_name2;
+
+ add_phi_arg (new_phi, loop_arg, new_exit_e);
+ add_phi_arg (new_phi, guard_arg, guard_edge);
+
+ /* 1.3. Update phi in successor block. */
+ gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi, e) == orig_def);
+ SET_PHI_ARG_DEF (update_phi, e->dest_idx, PHI_RESULT (new_phi));
+ update_phi2 = new_phi;
+
+
+ /** 2. Handle loop-closed-ssa-form phis **/
+
+ /* 2.1. Generate new phi node in NEW_EXIT_BB: */
+ new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)),
+ *new_exit_bb);
+
+ /* 2.2. NEW_EXIT_BB has one incoming edge: the exit-edge of the loop. */
+ add_phi_arg (new_phi, loop_arg, loop->single_exit);
+
+ /* 2.3. Update phi in successor of NEW_EXIT_BB: */
+ gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi2, new_exit_e) == loop_arg);
+ SET_PHI_ARG_DEF (update_phi2, new_exit_e->dest_idx, PHI_RESULT (new_phi));
+
+
+ /** 3. Handle loop-closed-ssa-form phis for first loop **/
+
+ /* 3.1. Find the relevant names that need an exit-phi in
+ GUARD_BB, i.e. names for which
+ slpeel_update_phi_nodes_for_guard1 had not already created a
+ phi node. This is the case for names that are used outside
+ the loop (and therefore need an exit phi) but are not updated
+ across loop iterations (and therefore don't have a
+ loop-header-phi).
+
+ slpeel_update_phi_nodes_for_guard1 is responsible for
+ creating loop-exit phis in GUARD_BB for names that have a
+ loop-header-phi. When such a phi is created we also record
+ the new name in its current definition. If this new name
+ exists, then guard_arg was set to this new name (see 1.2
+ above). Therefore, if guard_arg is not this new name, this
+ is an indication that an exit-phi in GUARD_BB was not yet
+ created, so we take care of it here. */
+ if (guard_arg == new_name2)
+ continue;
+ arg = guard_arg;
+
+ /* 3.2. Generate new phi node in GUARD_BB: */
+ new_phi = create_phi_node (SSA_NAME_VAR (PHI_RESULT (orig_phi)),
+ guard_edge->src);
+
+ /* 3.3. GUARD_BB has one incoming edge: */
+ gcc_assert (EDGE_COUNT (guard_edge->src->preds) == 1);
+ add_phi_arg (new_phi, arg, EDGE_PRED (guard_edge->src, 0));
+
+ /* 3.4. Update phi in successor of GUARD_BB: */
+ gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi2, guard_edge)
+ == guard_arg);
+ SET_PHI_ARG_DEF (update_phi2, guard_edge->dest_idx, PHI_RESULT (new_phi));
+ }
+
+ set_phi_nodes (new_merge_bb, phi_reverse (phi_nodes (new_merge_bb)));
}
/* Make the LOOP iterate NITERS times. This is done by adding a new IV
- that starts at zero, increases by one and its limit is NITERS. */
+ that starts at zero, increases by one and its limit is NITERS.
-static void
-slpeel_make_loop_iterate_ntimes (struct loop *loop, tree niters,
- tree begin_label, tree exit_label)
+ Assumption: the exit-condition of LOOP is the last stmt in the loop. */
+
+void
+slpeel_make_loop_iterate_ntimes (struct loop *loop, tree niters)
{
tree indx_before_incr, indx_after_incr, cond_stmt, cond;
tree orig_cond;
- edge exit_edge = loop->exit_edges[0];
- block_stmt_iterator loop_exit_bsi = bsi_last (exit_edge->src);
+ edge exit_edge = loop->single_exit;
+ block_stmt_iterator loop_cond_bsi;
+ block_stmt_iterator incr_bsi;
+ bool insert_after;
+ tree begin_label = tree_block_label (loop->latch);
+ tree exit_label = tree_block_label (loop->single_exit->dest);
+ tree init = build_int_cst (TREE_TYPE (niters), 0);
+ tree step = build_int_cst (TREE_TYPE (niters), 1);
+ tree then_label;
+ tree else_label;
+ LOC loop_loc;
- /* Flow loop scan does not update loop->single_exit field. */
- loop->single_exit = loop->exit_edges[0];
orig_cond = get_loop_exit_condition (loop);
gcc_assert (orig_cond);
- create_iv (integer_zero_node, integer_one_node, NULL_TREE, loop,
- &loop_exit_bsi, false, &indx_before_incr, &indx_after_incr);
-
- /* CREATE_IV uses BSI_INSERT with TSI_NEW_STMT, so we want to get
- back to the exit condition statement. */
- bsi_next (&loop_exit_bsi);
- gcc_assert (bsi_stmt (loop_exit_bsi) == orig_cond);
+ loop_cond_bsi = bsi_for_stmt (orig_cond);
+ standard_iv_increment_position (loop, &incr_bsi, &insert_after);
+ create_iv (init, step, NULL_TREE, loop,
+ &incr_bsi, insert_after, &indx_before_incr, &indx_after_incr);
if (exit_edge->flags & EDGE_TRUE_VALUE) /* 'then' edge exits the loop. */
- cond = build2 (GE_EXPR, boolean_type_node, indx_after_incr, niters);
+ {
+ cond = build2 (GE_EXPR, boolean_type_node, indx_after_incr, niters);
+ then_label = build1 (GOTO_EXPR, void_type_node, exit_label);
+ else_label = build1 (GOTO_EXPR, void_type_node, begin_label);
+ }
else /* 'then' edge loops back. */
- cond = build2 (LT_EXPR, boolean_type_node, indx_after_incr, niters);
+ {
+ cond = build2 (LT_EXPR, boolean_type_node, indx_after_incr, niters);
+ then_label = build1 (GOTO_EXPR, void_type_node, begin_label);
+ else_label = build1 (GOTO_EXPR, void_type_node, exit_label);
+ }
- begin_label = build1 (GOTO_EXPR, void_type_node, begin_label);
- exit_label = build1 (GOTO_EXPR, void_type_node, exit_label);
- cond_stmt = build (COND_EXPR, TREE_TYPE (orig_cond), cond,
- begin_label, exit_label);
- bsi_insert_before (&loop_exit_bsi, cond_stmt, BSI_SAME_STMT);
+ cond_stmt = build3 (COND_EXPR, TREE_TYPE (orig_cond), cond,
+ then_label, else_label);
+ bsi_insert_before (&loop_cond_bsi, cond_stmt, BSI_SAME_STMT);
/* Remove old loop exit test: */
- bsi_remove (&loop_exit_bsi);
+ bsi_remove (&loop_cond_bsi, true);
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- print_generic_expr (dump_file, cond_stmt, TDF_SLIM);
+ loop_loc = find_loop_location (loop);
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ if (loop_loc != UNKNOWN_LOC)
+ fprintf (dump_file, "\nloop at %s:%d: ",
+ LOC_FILE (loop_loc), LOC_LINE (loop_loc));
+ print_generic_expr (dump_file, cond_stmt, TDF_SLIM);
+ }
loop->nb_iterations = niters;
}
basic_block exit_dest;
tree phi, phi_arg;
- at_exit = (e == loop->exit_edges[0]);
+ at_exit = (e == loop->single_exit);
if (!at_exit && e != loop_preheader_edge (loop))
- {
- if (dump_file && (dump_flags & TDF_DETAILS))
- fprintf (dump_file,
- "Edge is not an entry nor an exit edge.\n");
- return NULL;
- }
+ return NULL;
bbs = get_loop_body (loop);
/* Check whether duplication is possible. */
if (!can_copy_bbs_p (bbs, loop->num_nodes))
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "Cannot copy basic blocks.\n");
free (bbs);
return NULL;
}
new_loop = duplicate_loop (loops, loop, loop->outer);
if (!new_loop)
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "The duplicate_loop returns NULL.\n");
free (bbs);
return NULL;
}
- exit_dest = loop->exit_edges[0]->dest;
+ exit_dest = loop->single_exit->dest;
was_imm_dom = (get_immediate_dominator (CDI_DOMINATORS,
exit_dest) == loop->header ?
true : false);
- new_bbs = xmalloc (sizeof (basic_block) * loop->num_nodes);
+ new_bbs = XNEWVEC (basic_block, loop->num_nodes);
- copy_bbs (bbs, loop->num_nodes, new_bbs, NULL, 0, NULL, NULL);
+ copy_bbs (bbs, loop->num_nodes, new_bbs,
+ &loop->single_exit, 1, &new_loop->single_exit, NULL,
+ e->src);
/* Duplicating phi args at exit bbs as coming
also from exit of duplicated loop. */
for (phi = phi_nodes (exit_dest); phi; phi = PHI_CHAIN (phi))
{
- phi_arg = PHI_ARG_DEF_FROM_EDGE (phi, loop->exit_edges[0]);
+ phi_arg = PHI_ARG_DEF_FROM_EDGE (phi, loop->single_exit);
if (phi_arg)
{
edge new_loop_exit_edge;
else
new_loop_exit_edge = EDGE_SUCC (new_loop->header, 0);
- add_phi_arg (&phi, phi_arg, new_loop_exit_edge);
+ add_phi_arg (phi, phi_arg, new_loop_exit_edge);
}
}
{
phi_arg = PHI_ARG_DEF_FROM_EDGE (phi, entry_e);
if (phi_arg)
- add_phi_arg (&phi, phi_arg, new_exit_e);
+ add_phi_arg (phi, phi_arg, new_exit_e);
}
redirect_edge_and_branch_force (entry_e, new_loop->header);
set_immediate_dominator (CDI_DOMINATORS, new_loop->header, preheader);
}
- flow_loop_scan (new_loop, LOOP_ALL);
- flow_loop_scan (loop, LOOP_ALL);
free (new_bbs);
free (bbs);
Returns the skip edge. */
static edge
-slpeel_add_loop_guard (basic_block guard_bb, tree cond, basic_block exit_bb)
+slpeel_add_loop_guard (basic_block guard_bb, tree cond, basic_block exit_bb,
+ basic_block dom_bb)
{
block_stmt_iterator bsi;
edge new_e, enter_e;
tree_block_label (exit_bb));
else_label = build1 (GOTO_EXPR, void_type_node,
tree_block_label (enter_e->dest));
- cond_stmt = build (COND_EXPR, void_type_node, cond,
+ cond_stmt = build3 (COND_EXPR, void_type_node, cond,
then_label, else_label);
bsi_insert_after (&bsi, cond_stmt, BSI_NEW_STMT);
- /* Add new edge to connect entry block to the second loop. */
+ /* Add new edge to connect guard block to the merge/loop-exit block. */
new_e = make_edge (guard_bb, exit_bb, EDGE_TRUE_VALUE);
- set_immediate_dominator (CDI_DOMINATORS, exit_bb, guard_bb);
+ set_immediate_dominator (CDI_DOMINATORS, exit_bb, dom_bb);
return new_e;
}
-/* This function verifies that certain restrictions apply to LOOP. */
+/* This function verifies that the following restrictions apply to LOOP:
+ (1) it is innermost
+ (2) it consists of exactly 2 basic blocks - header, and an empty latch.
+ (3) it is single entry, single exit
+ (4) its exit condition is the last stmt in the header
+ (5) E is the entry/exit edge of LOOP.
+ */
-static bool
-slpeel_verify_loop_for_duplication (struct loop *loop,
- bool update_first_loop_count, edge e)
+bool
+slpeel_can_duplicate_loop_p (struct loop *loop, edge e)
{
- edge exit_e = loop->exit_edges [0];
+ edge exit_e = loop->single_exit;
edge entry_e = loop_preheader_edge (loop);
+ tree orig_cond = get_loop_exit_condition (loop);
+ block_stmt_iterator loop_exit_bsi = bsi_last (exit_e->src);
- /* We duplicate only innermost loops. */
- if (loop->inner)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "Loop duplication failed. Loop is not innermost.\n");
- return false;
- }
-
- /* Only loops with 1 exit. */
- if (loop->num_exits != 1)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "More than one exit from loop.\n");
- return false;
- }
-
- /* Only loops with 1 entry. */
- if (loop->num_entries != 1)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "More than one exit from loop.\n");
- return false;
- }
-
- /* All loops has outers, the only case loop->outer is NULL is for
- the function itself. */
- if (!loop->outer)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "Loop is outer-most loop.\n");
- return false;
- }
-
- /* Verify that new IV can be created and loop condition
- can be changed to make first loop iterate first_niters times. */
- if (!update_first_loop_count)
- {
- tree orig_cond = get_loop_exit_condition (loop);
- block_stmt_iterator loop_exit_bsi = bsi_last (exit_e->src);
-
- if (!orig_cond)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "Loop has no exit condition.\n");
- return false;
- }
- if (orig_cond != bsi_stmt (loop_exit_bsi))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "Loop exit condition is not loop header last stmt.\n");
- return false;
- }
- }
+ if (need_ssa_update_p ())
+ return false;
- /* Make sure E is either an entry or an exit edge. */
- if (e != exit_e && e != entry_e)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "E is not loop entry or exit edge.\n");
- return false;
- }
+ if (loop->inner
+ /* All loops have an outer scope; the only case loop->outer is NULL is for
+ the function itself. */
+ || !loop->outer
+ || loop->num_nodes != 2
+ || !empty_block_p (loop->latch)
+ || !loop->single_exit
+ /* Verify that new loop exit condition can be trivially modified. */
+ || (!orig_cond || orig_cond != bsi_stmt (loop_exit_bsi))
+ || (e != exit_e && e != entry_e))
+ return false;
return true;
}
+#ifdef ENABLE_CHECKING
+void
+slpeel_verify_cfg_after_peeling (struct loop *first_loop,
+ struct loop *second_loop)
+{
+ basic_block loop1_exit_bb = first_loop->single_exit->dest;
+ basic_block loop2_entry_bb = loop_preheader_edge (second_loop)->src;
+ basic_block loop1_entry_bb = loop_preheader_edge (first_loop)->src;
-/* Given LOOP this function duplicates it to the edge E.
-
- This transformation takes place before the loop is vectorized.
- For now, there are two main cases when it's used
- by the vectorizer: to support loops with unknown loop bounds
- (or loop bounds indivisible by vectorization factor) and to force the
- alignment of data references in the loop. In the first case, LOOP is
- duplicated to the exit edge, producing epilog loop. In the second case, LOOP
- is duplicated to the preheader edge thus generating prolog loop. In both
- cases, the original loop will be vectorized after the transformation.
-
- The edge E is supposed to be either preheader edge of the LOOP or
- its exit edge. If preheader edge is specified, the LOOP copy
- will precede the original one. Otherwise the copy will be located
- at the exit of the LOOP.
-
- FIRST_NITERS (SSA_NAME) parameter specifies how many times to iterate
- the first loop. If UPDATE_FIRST_LOOP_COUNT parameter is false, the first
- loop will be iterated FIRST_NITERS times by introducing additional
- induction variable and replacing loop exit condition. If
- UPDATE_FIRST_LOOP_COUNT is true no change to the first loop is made and
- the caller to tree_duplicate_loop_to_edge is responsible for updating
- the first loop count.
+ /* A guard that controls whether the second_loop is to be executed or skipped
+ is placed in first_loop->exit. first_loopt->exit therefore has two
+ successors - one is the preheader of second_loop, and the other is a bb
+ after second_loop.
+ */
+ gcc_assert (EDGE_COUNT (loop1_exit_bb->succs) == 2);
- NITERS (also SSA_NAME) parameter defines the number of iteration the
- original loop iterated. The function generates two if-then guards:
- one prior to the first loop and the other prior to the second loop.
- The first guard will be:
-
- if (FIRST_NITERS == 0) then skip the first loop
+ /* 1. Verify that one of the successors of first_loopt->exit is the preheader
+ of second_loop. */
- The second guard will be:
-
- if (FIRST_NITERS == NITERS) then skip the second loop
+ /* The preheader of new_loop is expected to have two predecessors:
+ first_loop->exit and the block that precedes first_loop. */
+
+ gcc_assert (EDGE_COUNT (loop2_entry_bb->preds) == 2
+ && ((EDGE_PRED (loop2_entry_bb, 0)->src == loop1_exit_bb
+ && EDGE_PRED (loop2_entry_bb, 1)->src == loop1_entry_bb)
+ || (EDGE_PRED (loop2_entry_bb, 1)->src == loop1_exit_bb
+ && EDGE_PRED (loop2_entry_bb, 0)->src == loop1_entry_bb)));
+
+ /* Verify that the other successor of first_loopt->exit is after the
+ second_loop. */
+ /* TODO */
+}
+#endif
- Thus the equivalence to the original code is guaranteed by correct values
- of NITERS and FIRST_NITERS and generation of if-then loop guards.
+/* Function slpeel_tree_peel_loop_to_edge.
- For now this function supports only loop forms that are candidate for
- vectorization. Such types are the following:
+ Peel the first (last) iterations of LOOP into a new prolog (epilog) loop
+ that is placed on the entry (exit) edge E of LOOP. After this transformation
+ we have two loops one after the other - first-loop iterates FIRST_NITERS
+ times, and second-loop iterates the remainder NITERS - FIRST_NITERS times.
- (1) only innermost loops
- (2) loops built from 2 basic blocks
- (3) loops with one entry and one exit
- (4) loops without function calls
- (5) loops without defs that are used after the loop
+ Input:
+ - LOOP: the loop to be peeled.
+ - E: the exit or entry edge of LOOP.
+ If it is the entry edge, we peel the first iterations of LOOP. In this
+ case first-loop is LOOP, and second-loop is the newly created loop.
+ If it is the exit edge, we peel the last iterations of LOOP. In this
+ case, first-loop is the newly created loop, and second-loop is LOOP.
+ - NITERS: the number of iterations that LOOP iterates.
+ - FIRST_NITERS: the number of iterations that the first-loop should iterate.
+ - UPDATE_FIRST_LOOP_COUNT: specified whether this function is responsible
+ for updating the loop bound of the first-loop to FIRST_NITERS. If it
+ is false, the caller of this function may want to take care of this
+ (this can be useful if we don't want new stmts added to first-loop).
- (1), (3) are checked in this function; (2) - in function
- vect_analyze_loop_form; (4) - in function vect_analyze_data_refs;
- (5) is checked as part of the function vect_mark_stmts_to_be_vectorized,
- when excluding induction/reduction support.
+ Output:
+ The function returns a pointer to the new loop-copy, or NULL if it failed
+ to perform the transformation.
+
+ The function generates two if-then-else guards: one before the first loop,
+ and the other before the second loop:
+ The first guard is:
+ if (FIRST_NITERS == 0) then skip the first loop,
+ and go directly to the second loop.
+ The second guard is:
+ if (FIRST_NITERS == NITERS) then skip the second loop.
+
+ FORNOW only simple loops are supported (see slpeel_can_duplicate_loop_p).
+ FORNOW the resulting code will not be in loop-closed-ssa form.
+*/
- The function returns NULL in case one of these checks or
- transformations failed. */
-
struct loop*
slpeel_tree_peel_loop_to_edge (struct loop *loop, struct loops *loops,
edge e, tree first_niters,
edge skip_e;
tree pre_condition;
bitmap definitions;
- basic_block first_exit_bb, second_exit_bb;
- basic_block pre_header_bb;
- edge exit_e = loop->exit_edges [0];
-
- gcc_assert (!any_marked_for_rewrite_p ());
-
- if (!slpeel_verify_loop_for_duplication (loop, update_first_loop_count, e))
- return NULL;
-
- /* We have to initialize cfg_hooks. Then, when calling
+ basic_block bb_before_second_loop, bb_after_second_loop;
+ basic_block bb_before_first_loop;
+ basic_block bb_between_loops;
+ basic_block new_exit_bb;
+ edge exit_e = loop->single_exit;
+ LOC loop_loc;
+
+ if (!slpeel_can_duplicate_loop_p (loop, e))
+ return NULL;
+
+ /* We have to initialize cfg_hooks. Then, when calling
cfg_hooks->split_edge, the function tree_split_edge
- is actually called and, when calling cfg_hooks->duplicate_block,
+ is actually called and, when calling cfg_hooks->duplicate_block,
the function tree_duplicate_bb is called. */
tree_register_cfg_hooks ();
- /* 1. Generate a copy of LOOP and put it on E (entry or exit). */
+
+ /* 1. Generate a copy of LOOP and put it on E (E is the entry/exit of LOOP).
+ Resulting CFG would be:
+
+ first_loop:
+ do {
+ } while ...
+
+ second_loop:
+ do {
+ } while ...
+
+ orig_exit_bb:
+ */
+
if (!(new_loop = slpeel_tree_duplicate_loop_to_edge_cfg (loop, loops, e)))
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "The tree_duplicate_loop_to_edge_cfg failed.\n");
+ loop_loc = find_loop_location (loop);
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ if (loop_loc != UNKNOWN_LOC)
+ fprintf (dump_file, "\n%s:%d: note: ",
+ LOC_FILE (loop_loc), LOC_LINE (loop_loc));
+ fprintf (dump_file, "tree_duplicate_loop_to_edge_cfg failed.\n");
+ }
return NULL;
}
-
- definitions = marked_ssa_names ();
- allocate_new_names (definitions);
- slpeel_update_phis_for_duplicate_loop (loop, new_loop, e == exit_e);
- /* Here, using assumption (5), we do not propagate new names further
- than on phis of the exit from the second loop. */
- rename_variables_in_loop (new_loop);
- free_new_names (definitions);
-
+
if (e == exit_e)
{
+ /* NEW_LOOP was placed after LOOP. */
first_loop = loop;
second_loop = new_loop;
}
- else
+ else
{
+ /* NEW_LOOP was placed before LOOP. */
first_loop = new_loop;
second_loop = loop;
}
- /* 2. Generate bb between the loops. */
- first_exit_bb = split_edge (first_loop->exit_edges[0]);
- add_bb_to_loop (first_exit_bb, first_loop->outer);
-
- /* We need to update here first loop exit edge
- and second loop preheader edge. */
- flow_loop_scan (first_loop, LOOP_ALL);
- flow_loop_scan (second_loop, LOOP_ALL);
+ definitions = ssa_names_to_replace ();
+ slpeel_update_phis_for_duplicate_loop (loop, new_loop, e == exit_e);
+ rename_variables_in_loop (new_loop);
- /* 3. Make first loop iterate FIRST_NITERS times, if needed. */
- if (!update_first_loop_count)
- {
- tree first_loop_latch_lbl = tree_block_label (first_loop->latch);
- tree first_loop_exit_lbl = tree_block_label (first_exit_bb);
- slpeel_make_loop_iterate_ntimes (first_loop, first_niters,
- first_loop_latch_lbl,
- first_loop_exit_lbl);
- }
-
- /* 4. Add the guard before first loop:
+ /* 2. Add the guard that controls whether the first loop is executed.
+ Resulting CFG would be:
- if FIRST_NITERS == 0
- skip first loop
- else
- enter first loop */
+ bb_before_first_loop:
+ if (FIRST_NITERS == 0) GOTO bb_before_second_loop
+ GOTO first-loop
- /* 4a. Generate bb before first loop. */
- pre_header_bb = split_edge (loop_preheader_edge (first_loop));
- add_bb_to_loop (pre_header_bb, first_loop->outer);
+ first_loop:
+ do {
+ } while ...
- /* First loop preheader edge is changed. */
- flow_loop_scan (first_loop, LOOP_ALL);
+ bb_before_second_loop:
- /* 4b. Generate guard condition. */
- pre_condition = build (LE_EXPR, boolean_type_node,
- first_niters, integer_zero_node);
+ second_loop:
+ do {
+ } while ...
- /* 4c. Add condition at the end of preheader bb. */
- skip_e = slpeel_add_loop_guard (pre_header_bb, pre_condition, first_exit_bb);
+ orig_exit_bb:
+ */
- /* 4d. Update phis at first loop exit and propagate changes
- to the phis of second loop. */
- slpeel_update_phi_nodes_for_guard (skip_e, first_loop);
+ bb_before_first_loop = split_edge (loop_preheader_edge (first_loop));
+ add_bb_to_loop (bb_before_first_loop, first_loop->outer);
+ bb_before_second_loop = split_edge (first_loop->single_exit);
+ add_bb_to_loop (bb_before_second_loop, first_loop->outer);
- /* 5. Add the guard before second loop:
+ pre_condition =
+ fold_build2 (LE_EXPR, boolean_type_node, first_niters,
+ build_int_cst (TREE_TYPE (first_niters), 0));
+ skip_e = slpeel_add_loop_guard (bb_before_first_loop, pre_condition,
+ bb_before_second_loop, bb_before_first_loop);
+ slpeel_update_phi_nodes_for_guard1 (skip_e, first_loop,
+ first_loop == new_loop,
+ &new_exit_bb, &definitions);
- if FIRST_NITERS == NITERS SKIP
- skip second loop
- else
- enter second loop */
- /* 5a. Generate empty bb at the exit from the second loop. */
- second_exit_bb = split_edge (second_loop->exit_edges[0]);
- add_bb_to_loop (second_exit_bb, second_loop->outer);
+ /* 3. Add the guard that controls whether the second loop is executed.
+ Resulting CFG would be:
- /* Second loop preheader edge is changed. */
- flow_loop_scan (second_loop, LOOP_ALL);
+ bb_before_first_loop:
+ if (FIRST_NITERS == 0) GOTO bb_before_second_loop (skip first loop)
+ GOTO first-loop
- /* 5b. Generate guard condition. */
- pre_condition = build (EQ_EXPR, boolean_type_node,
- first_niters, niters);
+ first_loop:
+ do {
+ } while ...
- /* 5c. Add condition at the end of preheader bb. */
- skip_e = slpeel_add_loop_guard (first_exit_bb, pre_condition, second_exit_bb);
- slpeel_update_phi_nodes_for_guard (skip_e, second_loop);
+ bb_between_loops:
+ if (FIRST_NITERS == NITERS) GOTO bb_after_second_loop (skip second loop)
+ GOTO bb_before_second_loop
- BITMAP_XFREE (definitions);
- unmark_all_for_rewrite ();
-
- return new_loop;
-}
+ bb_before_second_loop:
+ second_loop:
+ do {
+ } while ...
-\f
-/* Here the proper Vectorizer starts. */
+ bb_after_second_loop:
-/*************************************************************************
- Vectorization Utilities.
- *************************************************************************/
+ orig_exit_bb:
+ */
-/* Function new_stmt_vec_info.
+ bb_between_loops = new_exit_bb;
+ bb_after_second_loop = split_edge (second_loop->single_exit);
+ add_bb_to_loop (bb_after_second_loop, second_loop->outer);
- Create and initialize a new stmt_vec_info struct for STMT. */
+ pre_condition =
+ fold_build2 (EQ_EXPR, boolean_type_node, first_niters, niters);
+ skip_e = slpeel_add_loop_guard (bb_between_loops, pre_condition,
+ bb_after_second_loop, bb_before_first_loop);
+ slpeel_update_phi_nodes_for_guard2 (skip_e, second_loop,
+ second_loop == new_loop, &new_exit_bb);
-stmt_vec_info
-new_stmt_vec_info (tree stmt, struct loop *loop)
-{
- stmt_vec_info res;
- res = (stmt_vec_info) xcalloc (1, sizeof (struct _stmt_vec_info));
+ /* 4. Make first-loop iterate FIRST_NITERS times, if requested.
+ */
+ if (update_first_loop_count)
+ slpeel_make_loop_iterate_ntimes (first_loop, first_niters);
- STMT_VINFO_TYPE (res) = undef_vec_info_type;
- STMT_VINFO_STMT (res) = stmt;
- STMT_VINFO_LOOP (res) = loop;
- STMT_VINFO_RELEVANT_P (res) = 0;
- STMT_VINFO_VECTYPE (res) = NULL;
- STMT_VINFO_VEC_STMT (res) = NULL;
- STMT_VINFO_DATA_REF (res) = NULL;
- STMT_VINFO_MEMTAG (res) = NULL;
- STMT_VINFO_VECT_DR_BASE (res) = NULL;
+ BITMAP_FREE (definitions);
+ delete_update_ssa ();
- return res;
+ return new_loop;
}
+/* Function vect_get_loop_location.
-/* Function new_loop_vec_info.
-
- Create and initialize a new loop_vec_info struct for LOOP, as well as
- stmt_vec_info structs for all the stmts in LOOP. */
+ Extract the location of the loop in the source code.
+ If the loop is not well formed for vectorization, an estimated
+ location is calculated.
+ Return the loop location if succeed and NULL if not. */
-loop_vec_info
-new_loop_vec_info (struct loop *loop)
+LOC
+find_loop_location (struct loop *loop)
{
- loop_vec_info res;
- basic_block *bbs;
+ tree node = NULL_TREE;
+ basic_block bb;
block_stmt_iterator si;
- unsigned int i;
- res = (loop_vec_info) xcalloc (1, sizeof (struct _loop_vec_info));
+ if (!loop)
+ return UNKNOWN_LOC;
- bbs = get_loop_body (loop);
+ node = get_loop_exit_condition (loop);
- /* Create stmt_info for all stmts in the loop. */
- for (i = 0; i < loop->num_nodes; i++)
- {
- basic_block bb = bbs[i];
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- tree stmt = bsi_stmt (si);
- stmt_ann_t ann;
-
- get_stmt_operands (stmt);
- ann = stmt_ann (stmt);
- set_stmt_info (ann, new_stmt_vec_info (stmt, loop));
- }
- }
-
- LOOP_VINFO_LOOP (res) = loop;
- LOOP_VINFO_BBS (res) = bbs;
- LOOP_VINFO_EXIT_COND (res) = NULL;
- LOOP_VINFO_NITERS (res) = NULL;
- LOOP_VINFO_VECTORIZABLE_P (res) = 0;
- LOOP_DO_PEELING_FOR_ALIGNMENT (res) = false;
- LOOP_VINFO_VECT_FACTOR (res) = 0;
- VARRAY_GENERIC_PTR_INIT (LOOP_VINFO_DATAREF_WRITES (res), 20,
- "loop_write_datarefs");
- VARRAY_GENERIC_PTR_INIT (LOOP_VINFO_DATAREF_READS (res), 20,
- "loop_read_datarefs");
- LOOP_VINFO_UNALIGNED_DR (res) = NULL;
-
- return res;
-}
-
-
-/* Function destroy_loop_vec_info.
-
- Free LOOP_VINFO struct, as well as all the stmt_vec_info structs of all the
- stmts in the loop. */
-
-void
-destroy_loop_vec_info (loop_vec_info loop_vinfo)
-{
- struct loop *loop;
- basic_block *bbs;
- int nbbs;
- block_stmt_iterator si;
- int j;
+ if (node && EXPR_P (node) && EXPR_HAS_LOCATION (node)
+ && EXPR_FILENAME (node) && EXPR_LINENO (node))
+ return EXPR_LOC (node);
- if (!loop_vinfo)
- return;
+ /* If we got here the loop is probably not "well formed",
+ try to estimate the loop location */
- loop = LOOP_VINFO_LOOP (loop_vinfo);
+ if (!loop->header)
+ return UNKNOWN_LOC;
- bbs = LOOP_VINFO_BBS (loop_vinfo);
- nbbs = loop->num_nodes;
+ bb = loop->header;
- for (j = 0; j < nbbs; j++)
+ for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
{
- basic_block bb = bbs[j];
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- tree stmt = bsi_stmt (si);
- stmt_ann_t ann = stmt_ann (stmt);
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- free (stmt_info);
- set_stmt_info (ann, NULL);
- }
+ node = bsi_stmt (si);
+ if (node && EXPR_P (node) && EXPR_HAS_LOCATION (node))
+ return EXPR_LOC (node);
}
- free (LOOP_VINFO_BBS (loop_vinfo));
- varray_clear (LOOP_VINFO_DATAREF_WRITES (loop_vinfo));
- varray_clear (LOOP_VINFO_DATAREF_READS (loop_vinfo));
-
- free (loop_vinfo);
+ return UNKNOWN_LOC;
}
-/* Function debug_loop_stats.
+/*************************************************************************
+ Vectorization Debug Information.
+ *************************************************************************/
+
+/* Function vect_set_verbosity_level.
- For vectorization statistics dumps. */
+ Called from toplev.c upon detection of the
+ -ftree-vectorizer-verbose=N option. */
-static bool
-vect_debug_stats (struct loop *loop)
+void
+vect_set_verbosity_level (const char *val)
{
- basic_block bb;
- block_stmt_iterator si;
- tree node = NULL_TREE;
+ unsigned int vl;
- if (!dump_file || !(dump_flags & TDF_STATS))
- return false;
+ vl = atoi (val);
+ if (vl < MAX_VERBOSITY_LEVEL)
+ vect_verbosity_level = vl;
+ else
+ vect_verbosity_level = MAX_VERBOSITY_LEVEL - 1;
+}
- if (!loop)
- {
- fprintf (dump_file, "\n");
- return true;
- }
- if (!loop->header)
- return false;
+/* Function vect_set_dump_settings.
- bb = loop->header;
+ Fix the verbosity level of the vectorizer if the
+ requested level was not set explicitly using the flag
+ -ftree-vectorizer-verbose=N.
+ Decide where to print the debugging information (dump_file/stderr).
+ If the user defined the verbosity level, but there is no dump file,
+ print to stderr, otherwise print to the dump file. */
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- node = bsi_stmt (si);
- if (node && EXPR_P (node) && EXPR_LOCUS (node))
- break;
- }
+static void
+vect_set_dump_settings (void)
+{
+ vect_dump = dump_file;
- if (node && EXPR_P (node) && EXPR_LOCUS (node)
- && EXPR_FILENAME (node) && EXPR_LINENO (node))
+ /* Check if the verbosity level was defined by the user: */
+ if (vect_verbosity_level != MAX_VERBOSITY_LEVEL)
{
- fprintf (dump_file, "\nloop at %s:%d: ",
- EXPR_FILENAME (node), EXPR_LINENO (node));
- return true;
+ /* If there is no dump file, print to stderr. */
+ if (!dump_file)
+ vect_dump = stderr;
+ return;
}
- return false;
+ /* User didn't specify verbosity level: */
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ vect_verbosity_level = REPORT_DETAILS;
+ else if (dump_file && (dump_flags & TDF_STATS))
+ vect_verbosity_level = REPORT_UNVECTORIZED_LOOPS;
+ else
+ vect_verbosity_level = REPORT_NONE;
+
+ gcc_assert (dump_file || vect_verbosity_level == REPORT_NONE);
}
For vectorization debug dumps. */
-static bool
-vect_debug_details (struct loop *loop)
+bool
+vect_print_dump_info (enum verbosity_levels vl)
{
- basic_block bb;
- block_stmt_iterator si;
- tree node = NULL_TREE;
-
- if (!dump_file || !(dump_flags & TDF_DETAILS))
+ if (vl > vect_verbosity_level)
return false;
- if (!loop)
- {
- fprintf (dump_file, "\n");
- return true;
- }
-
- if (!loop->header)
+ if (!current_function_decl || !vect_dump)
return false;
- bb = loop->header;
-
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- node = bsi_stmt (si);
- if (node && EXPR_P (node) && EXPR_LOCUS (node))
- break;
- }
-
- if (node && EXPR_P (node) && EXPR_LOCUS (node)
- && EXPR_FILENAME (node) && EXPR_LINENO (node))
- {
- fprintf (dump_file, "\nloop at %s:%d: ",
- EXPR_FILENAME (node), EXPR_LINENO (node));
- return true;
- }
+ if (vect_loop_location == UNKNOWN_LOC)
+ fprintf (vect_dump, "\n%s:%d: note: ",
+ DECL_SOURCE_FILE (current_function_decl),
+ DECL_SOURCE_LINE (current_function_decl));
+ else
+ fprintf (vect_dump, "\n%s:%d: note: ",
+ LOC_FILE (vect_loop_location), LOC_LINE (vect_loop_location));
- return false;
+ return true;
}
-/* Function vect_get_ptr_offset
+/*************************************************************************
+ Vectorization Utilities.
+ *************************************************************************/
+
+/* Function new_stmt_vec_info.
- Compute the OFFSET modulo vector-type alignment of pointer REF in bits. */
+ Create and initialize a new stmt_vec_info struct for STMT. */
-static tree
-vect_get_ptr_offset (tree ref ATTRIBUTE_UNUSED,
- tree vectype ATTRIBUTE_UNUSED,
- tree *offset ATTRIBUTE_UNUSED)
+stmt_vec_info
+new_stmt_vec_info (tree stmt, loop_vec_info loop_vinfo)
{
- /* TODO: Use alignment information. */
- return NULL_TREE;
+ stmt_vec_info res;
+ res = (stmt_vec_info) xcalloc (1, sizeof (struct _stmt_vec_info));
+
+ STMT_VINFO_TYPE (res) = undef_vec_info_type;
+ STMT_VINFO_STMT (res) = stmt;
+ STMT_VINFO_LOOP_VINFO (res) = loop_vinfo;
+ STMT_VINFO_RELEVANT_P (res) = 0;
+ STMT_VINFO_LIVE_P (res) = 0;
+ STMT_VINFO_VECTYPE (res) = NULL;
+ STMT_VINFO_VEC_STMT (res) = NULL;
+ STMT_VINFO_IN_PATTERN_P (res) = false;
+ STMT_VINFO_RELATED_STMT (res) = NULL;
+ STMT_VINFO_DATA_REF (res) = NULL;
+ if (TREE_CODE (stmt) == PHI_NODE)
+ STMT_VINFO_DEF_TYPE (res) = vect_unknown_def_type;
+ else
+ STMT_VINFO_DEF_TYPE (res) = vect_loop_def;
+ STMT_VINFO_SAME_ALIGN_REFS (res) = VEC_alloc (dr_p, heap, 5);
+
+ return res;
}
-/* Function vect_get_base_and_bit_offset
+/* Function new_loop_vec_info.
- Return the BASE of the data reference EXPR.
- If VECTYPE is given, also compute the OFFSET from BASE in bits.
- E.g., for EXPR a.b[i] + 4B, BASE is a, and OFFSET is the overall offset in
- bits of 'a.b[i] + 4B' from a.
+ Create and initialize a new loop_vec_info struct for LOOP, as well as
+ stmt_vec_info structs for all the stmts in LOOP. */
- Input:
- EXPR - the memory reference that is being analyzed
- DR - the data_reference struct of the _original_ memory reference
- (Note: DR_REF (DR) is not necessarily EXPR)
- VECTYPE - the type that defines the alignment (i.e, we compute
- alignment relative to TYPE_ALIGN(VECTYPE))
-
- Output:
- BASE (returned value) - the base of the data reference EXPR.
- E.g, if EXPR is a.b[k].c[i][j] the returned
- base is a.
- OFFSET - offset of EXPR from BASE in bits
- BASE_ALIGNED_P - indicates if BASE is aligned
-
- If something unexpected is encountered (an unsupported form of data-ref),
- or if VECTYPE is given but OFFSET cannot be determined:
- then NULL_TREE is returned. */
-
-static tree
-vect_get_base_and_bit_offset (struct data_reference *dr,
- tree expr,
- tree vectype,
- loop_vec_info loop_vinfo,
- tree *offset,
- bool *base_aligned_p)
+loop_vec_info
+new_loop_vec_info (struct loop *loop)
{
- tree this_offset = size_zero_node;
- tree base = NULL_TREE;
- tree next_ref;
- tree oprnd0, oprnd1;
- struct data_reference *array_dr;
- enum tree_code code = TREE_CODE (expr);
+ loop_vec_info res;
+ basic_block *bbs;
+ block_stmt_iterator si;
+ unsigned int i;
- *base_aligned_p = false;
+ res = (loop_vec_info) xcalloc (1, sizeof (struct _loop_vec_info));
- switch (code)
+ bbs = get_loop_body (loop);
+
+ /* Create stmt_info for all stmts in the loop. */
+ for (i = 0; i < loop->num_nodes; i++)
{
- /* These cases end the recursion: */
- case VAR_DECL:
- *offset = size_zero_node;
- if (vectype && DECL_ALIGN (expr) >= TYPE_ALIGN (vectype))
- *base_aligned_p = true;
- return expr;
-
- case SSA_NAME:
- if (!vectype)
- return expr;
-
- if (TREE_CODE (TREE_TYPE (expr)) != POINTER_TYPE)
- return NULL_TREE;
-
- if (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (expr))) < TYPE_ALIGN (vectype))
- {
- base = vect_get_ptr_offset (expr, vectype, offset);
- if (base)
- *base_aligned_p = true;
- }
- else
- {
- *base_aligned_p = true;
- *offset = size_zero_node;
- base = expr;
- }
- return base;
-
- case INTEGER_CST:
- *offset = int_const_binop (MULT_EXPR, expr,
- build_int_cst (NULL_TREE, BITS_PER_UNIT), 1);
- return expr;
-
- /* These cases continue the recursion: */
- case COMPONENT_REF:
- oprnd0 = TREE_OPERAND (expr, 0);
- oprnd1 = TREE_OPERAND (expr, 1);
-
- this_offset = bit_position (oprnd1);
- if (vectype && !host_integerp (this_offset, 1))
- return NULL_TREE;
- next_ref = oprnd0;
- break;
+ basic_block bb = bbs[i];
+ tree phi;
- case ADDR_EXPR:
- oprnd0 = TREE_OPERAND (expr, 0);
- next_ref = oprnd0;
- break;
+ for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+ {
+ stmt_ann_t ann = get_stmt_ann (phi);
+ set_stmt_info (ann, new_stmt_vec_info (phi, res));
+ }
- case INDIRECT_REF:
- oprnd0 = TREE_OPERAND (expr, 0);
- next_ref = oprnd0;
- break;
-
- case ARRAY_REF:
- if (DR_REF (dr) != expr)
- /* Build array data_reference struct if the existing DR_REF
- doesn't match EXPR. This happens, for example, when the
- EXPR is *T and T is initialized to &arr[indx]. The DR struct
- contains information on the access of T, not of arr. In order
- to continue the analysis, we create a new DR struct that
- describes the access of arr.
- */
- array_dr = analyze_array (DR_STMT (dr), expr, DR_IS_READ (dr));
- else
- array_dr = dr;
-
- next_ref = vect_compute_array_ref_alignment (array_dr, loop_vinfo,
- vectype, &this_offset);
- if (!next_ref)
- return NULL_TREE;
-
- if (vectype &&
- TYPE_ALIGN (TREE_TYPE (TREE_TYPE (next_ref))) >= TYPE_ALIGN (vectype))
+ for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
{
- *offset = this_offset;
- *base_aligned_p = true;
- return next_ref;
+ tree stmt = bsi_stmt (si);
+ stmt_ann_t ann;
+
+ ann = stmt_ann (stmt);
+ set_stmt_info (ann, new_stmt_vec_info (stmt, res));
}
- break;
+ }
+
+ LOOP_VINFO_LOOP (res) = loop;
+ LOOP_VINFO_BBS (res) = bbs;
+ LOOP_VINFO_EXIT_COND (res) = NULL;
+ LOOP_VINFO_NITERS (res) = NULL;
+ LOOP_VINFO_VECTORIZABLE_P (res) = 0;
+ LOOP_PEELING_FOR_ALIGNMENT (res) = 0;
+ LOOP_VINFO_VECT_FACTOR (res) = 0;
+ LOOP_VINFO_DATAREFS (res) = VEC_alloc (data_reference_p, heap, 10);
+ LOOP_VINFO_DDRS (res) = VEC_alloc (ddr_p, heap, 10 * 10);
+ LOOP_VINFO_UNALIGNED_DR (res) = NULL;
+ LOOP_VINFO_MAY_MISALIGN_STMTS (res)
+ = VEC_alloc (tree, heap, PARAM_VALUE (PARAM_VECT_MAX_VERSION_CHECKS));
- case PLUS_EXPR:
- case MINUS_EXPR:
- /* In case we have a PLUS_EXPR of the form
- (oprnd0 + oprnd1), we assume that only oprnd0 determines the base.
- This is verified in vect_get_symbl_and_dr. */
- oprnd0 = TREE_OPERAND (expr, 0);
- oprnd1 = TREE_OPERAND (expr, 1);
+ return res;
+}
- base = vect_get_base_and_bit_offset
- (dr, oprnd1, vectype, loop_vinfo, &this_offset, base_aligned_p);
- if (vectype && !base)
- return NULL_TREE;
- next_ref = oprnd0;
- break;
+/* Function destroy_loop_vec_info.
+
+ Free LOOP_VINFO struct, as well as all the stmt_vec_info structs of all the
+ stmts in the loop. */
- default:
- return NULL_TREE;
- }
+void
+destroy_loop_vec_info (loop_vec_info loop_vinfo)
+{
+ struct loop *loop;
+ basic_block *bbs;
+ int nbbs;
+ block_stmt_iterator si;
+ int j;
+
+ if (!loop_vinfo)
+ return;
+
+ loop = LOOP_VINFO_LOOP (loop_vinfo);
- base = vect_get_base_and_bit_offset (dr, next_ref, vectype,
- loop_vinfo, offset, base_aligned_p);
+ bbs = LOOP_VINFO_BBS (loop_vinfo);
+ nbbs = loop->num_nodes;
- if (vectype && base)
+ for (j = 0; j < nbbs; j++)
{
- *offset = int_const_binop (PLUS_EXPR, *offset, this_offset, 1);
- if (!host_integerp (*offset, 1) || TREE_OVERFLOW (*offset))
- return NULL_TREE;
+ basic_block bb = bbs[j];
+ tree phi;
+ stmt_vec_info stmt_info;
- if (vect_debug_details (NULL))
+ for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
{
- print_generic_expr (dump_file, expr, TDF_SLIM);
- fprintf (dump_file, " --> total offset for ref: ");
- print_generic_expr (dump_file, *offset, TDF_SLIM);
+ stmt_ann_t ann = stmt_ann (phi);
+
+ stmt_info = vinfo_for_stmt (phi);
+ free (stmt_info);
+ set_stmt_info (ann, NULL);
}
- }
- return base;
+
+ for (si = bsi_start (bb); !bsi_end_p (si); )
+ {
+ tree stmt = bsi_stmt (si);
+ stmt_ann_t ann = stmt_ann (stmt);
+ stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
+
+ if (stmt_info)
+ {
+ /* Check if this is a "pattern stmt" (introduced by the
+ vectorizer during the pattern recognition pass). */
+ bool remove_stmt_p = false;
+ tree orig_stmt = STMT_VINFO_RELATED_STMT (stmt_info);
+ if (orig_stmt)
+ {
+ stmt_vec_info orig_stmt_info = vinfo_for_stmt (orig_stmt);
+ if (orig_stmt_info
+ && STMT_VINFO_IN_PATTERN_P (orig_stmt_info))
+ remove_stmt_p = true;
+ }
+
+ /* Free stmt_vec_info. */
+ VEC_free (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmt_info));
+ free (stmt_info);
+ set_stmt_info (ann, NULL);
+
+ /* Remove dead "pattern stmts". */
+ if (remove_stmt_p)
+ bsi_remove (&si, true);
+ }
+ bsi_next (&si);
+ }
+ }
+
+ free (LOOP_VINFO_BBS (loop_vinfo));
+ free_data_refs (LOOP_VINFO_DATAREFS (loop_vinfo));
+ free_dependence_relations (LOOP_VINFO_DDRS (loop_vinfo));
+ VEC_free (tree, heap, LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo));
+
+ free (loop_vinfo);
}
Returns whether the alignment of a DECL can be forced to be aligned
on ALIGNMENT bit boundary. */
-static bool
+bool
vect_can_force_dr_alignment_p (tree decl, unsigned int alignment)
{
if (TREE_CODE (decl) != VAR_DECL)
if (DECL_EXTERNAL (decl))
return false;
+ if (TREE_ASM_WRITTEN (decl))
+ return false;
+
if (TREE_STATIC (decl))
return (alignment <= MAX_OFILE_ALIGNMENT);
else
}
-/* Function vect_get_new_vect_var.
+/* Function get_vectype_for_scalar_type.
- Returns a name for a new variable. The current naming scheme appends the
- prefix "vect_" or "vect_p" (depending on the value of VAR_KIND) to
- the name of vectorizer generated variables, and appends that to NAME if
- provided. */
+ Returns the vector type corresponding to SCALAR_TYPE as supported
+ by the target. */
-static tree
-vect_get_new_vect_var (tree type, enum vect_var_kind var_kind, const char *name)
+tree
+get_vectype_for_scalar_type (tree scalar_type)
{
- const char *prefix;
- int prefix_len;
- tree new_vect_var;
-
- if (var_kind == vect_simple_var)
- prefix = "vect_";
- else
- prefix = "vect_p";
-
- prefix_len = strlen (prefix);
-
- if (name)
- new_vect_var = create_tmp_var (type, concat (prefix, name, NULL));
- else
- new_vect_var = create_tmp_var (type, prefix);
-
- return new_vect_var;
-}
-
-
-/* Function vect_create_index_for_vector_ref.
-
- Create (and return) an index variable, along with it's update chain in the
- loop. This variable will be used to access a memory location in a vector
- operation.
-
- Input:
- LOOP: The loop being vectorized.
- BSI: The block_stmt_iterator where STMT is. Any new stmts created by this
- function can be added here, or in the loop pre-header.
-
- Output:
- Return an index that will be used to index a vector array. It is expected
- that a pointer to the first vector will be used as the base address for the
- indexed reference.
-
- FORNOW: we are not trying to be efficient, just creating a new index each
- time from scratch. At this time all vector references could use the same
- index.
-
- TODO: create only one index to be used by all vector references. Record
- the index in the LOOP_VINFO the first time this procedure is called and
- return it on subsequent calls. The increment of this index must be placed
- just before the conditional expression that ends the single block loop. */
+ enum machine_mode inner_mode = TYPE_MODE (scalar_type);
+ int nbytes = GET_MODE_SIZE (inner_mode);
+ int nunits;
+ tree vectype;
-static tree
-vect_create_index_for_vector_ref (struct loop *loop, block_stmt_iterator *bsi)
-{
- tree init, step;
- tree indx_before_incr, indx_after_incr;
+ if (nbytes == 0 || nbytes >= UNITS_PER_SIMD_WORD)
+ return NULL_TREE;
- /* It is assumed that the base pointer used for vectorized access contains
- the address of the first vector. Therefore the index used for vectorized
- access must be initialized to zero and incremented by 1. */
+ /* FORNOW: Only a single vector size per target (UNITS_PER_SIMD_WORD)
+ is expected. */
+ nunits = UNITS_PER_SIMD_WORD / nbytes;
- init = integer_zero_node;
- step = integer_one_node;
+ vectype = build_vector_type (scalar_type, nunits);
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "get vectype with %d units of type ", nunits);
+ print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
+ }
- /* Assuming that bsi_insert is used with BSI_NEW_STMT */
- create_iv (init, step, NULL_TREE, loop, bsi, false,
- &indx_before_incr, &indx_after_incr);
+ if (!vectype)
+ return NULL_TREE;
- return indx_before_incr;
-}
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "vectype: ");
+ print_generic_expr (vect_dump, vectype, TDF_SLIM);
+ }
+ if (!VECTOR_MODE_P (TYPE_MODE (vectype))
+ && !INTEGRAL_MODE_P (TYPE_MODE (vectype)))
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "mode not supported by target.");
+ return NULL_TREE;
+ }
-/* Function vect_create_addr_base_for_vector_ref.
-
- Create an expression that computes the address of the first memory location
- that will be accessed for a data reference.
-
- Input:
- STMT: The statement containing the data reference.
- NEW_STMT_LIST: Must be initialized to NULL_TREE or a statement list.
- OFFSET: Optional. If supplied, it is be added to the initial address.
-
- Output:
- 1. Return an SSA_NAME whose value is the address of the memory location of
- the first vector of the data reference.
- 2. If new_stmt_list is not NULL_TREE after return then the caller must insert
- these statement(s) which define the returned SSA_NAME.
-
- FORNOW: We are only handling array accesses with step 1. */
-
-static tree
-vect_create_addr_base_for_vector_ref (tree stmt,
- tree *new_stmt_list,
- tree offset)
-{
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
- tree data_ref_base = unshare_expr (STMT_VINFO_VECT_DR_BASE (stmt_info));
- tree base_name = unshare_expr (DR_BASE_NAME (dr));
- tree ref = DR_REF (dr);
- tree data_ref_base_type = TREE_TYPE (data_ref_base);
- tree scalar_type = TREE_TYPE (ref);
- tree scalar_ptr_type = build_pointer_type (scalar_type);
- tree access_fn;
- tree init_val, step, init_oval;
- bool ok;
- bool is_ptr_ref, is_array_ref, is_addr_expr;
- tree array_base;
- tree vec_stmt;
- tree new_temp;
- tree array_ref;
- tree addr_base, addr_expr;
- tree dest, new_stmt;
-
- /* Only the access function of the last index is relevant (i_n in
- a[i_1][i_2]...[i_n]), the others correspond to loop invariants. */
- access_fn = DR_ACCESS_FN (dr, 0);
- ok = vect_is_simple_iv_evolution (loop->num, access_fn, &init_oval, &step,
- true);
- if (!ok)
- init_oval = integer_zero_node;
-
- is_ptr_ref = TREE_CODE (data_ref_base_type) == POINTER_TYPE
- && TREE_CODE (data_ref_base) == SSA_NAME;
- is_array_ref = TREE_CODE (data_ref_base_type) == ARRAY_TYPE;
- is_addr_expr = TREE_CODE (data_ref_base) == ADDR_EXPR
- || TREE_CODE (data_ref_base) == PLUS_EXPR
- || TREE_CODE (data_ref_base) == MINUS_EXPR;
- gcc_assert (is_ptr_ref || is_array_ref || is_addr_expr);
-
- /** Create: &(base[init_val])
-
- if data_ref_base is an ARRAY_TYPE:
- base = data_ref_base
-
- if data_ref_base is the SSA_NAME of a POINTER_TYPE:
- base = *((scalar_array *) data_ref_base)
- **/
-
- if (is_array_ref)
- array_base = data_ref_base;
- else /* is_ptr_ref or is_addr_expr */
- {
- /* array_ptr = (scalar_array_ptr_type *) data_ref_base; */
- tree scalar_array_type = build_array_type (scalar_type, 0);
- tree scalar_array_ptr_type = build_pointer_type (scalar_array_type);
- tree array_ptr = create_tmp_var (scalar_array_ptr_type, "array_ptr");
- add_referenced_tmp_var (array_ptr);
-
- dest = create_tmp_var (TREE_TYPE (data_ref_base), "dataref");
- add_referenced_tmp_var (dest);
- data_ref_base =
- force_gimple_operand (data_ref_base, &new_stmt, false, dest);
- append_to_statement_list_force (new_stmt, new_stmt_list);
-
- vec_stmt = fold_convert (scalar_array_ptr_type, data_ref_base);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, array_ptr, vec_stmt);
- new_temp = make_ssa_name (array_ptr, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- append_to_statement_list_force (vec_stmt, new_stmt_list);
-
- /* (*array_ptr) */
- array_base = build_fold_indirect_ref (new_temp);
- }
-
- dest = create_tmp_var (TREE_TYPE (init_oval), "newinit");
- add_referenced_tmp_var (dest);
- init_val = force_gimple_operand (init_oval, &new_stmt, false, dest);
- append_to_statement_list_force (new_stmt, new_stmt_list);
-
- if (offset)
- {
- tree tmp = create_tmp_var (TREE_TYPE (init_val), "offset");
- add_referenced_tmp_var (tmp);
- vec_stmt = build2 (PLUS_EXPR, TREE_TYPE (init_val), init_val, offset);
- vec_stmt = build2 (MODIFY_EXPR, TREE_TYPE (init_val), tmp, vec_stmt);
- init_val = make_ssa_name (tmp, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = init_val;
- append_to_statement_list_force (vec_stmt, new_stmt_list);
- }
-
- array_ref = build4 (ARRAY_REF, scalar_type, array_base, init_val,
- NULL_TREE, NULL_TREE);
- addr_base = build_fold_addr_expr (array_ref);
-
- /* addr_expr = addr_base */
- addr_expr = vect_get_new_vect_var (scalar_ptr_type, vect_pointer_var,
- get_name (base_name));
- add_referenced_tmp_var (addr_expr);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, addr_expr, addr_base);
- new_temp = make_ssa_name (addr_expr, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- append_to_statement_list_force (vec_stmt, new_stmt_list);
-
- return new_temp;
-}
-
-
-/* Function get_vectype_for_scalar_type.
-
- Returns the vector type corresponding to SCALAR_TYPE as supported
- by the target. */
-
-static tree
-get_vectype_for_scalar_type (tree scalar_type)
-{
- enum machine_mode inner_mode = TYPE_MODE (scalar_type);
- int nbytes = GET_MODE_SIZE (inner_mode);
- int nunits;
- tree vectype;
-
- if (nbytes == 0)
- return NULL_TREE;
-
- /* FORNOW: Only a single vector size per target (UNITS_PER_SIMD_WORD)
- is expected. */
- nunits = UNITS_PER_SIMD_WORD / nbytes;
-
- vectype = build_vector_type (scalar_type, nunits);
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "get vectype with %d units of type ", nunits);
- print_generic_expr (dump_file, scalar_type, TDF_SLIM);
- }
-
- if (!vectype)
- return NULL_TREE;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "vectype: ");
- print_generic_expr (dump_file, vectype, TDF_SLIM);
- }
-
- if (!VECTOR_MODE_P (TYPE_MODE (vectype)))
- {
- /* TODO: tree-complex.c sometimes can parallelize operations
- on generic vectors. We can vectorize the loop in that case,
- but then we should re-run the lowering pass. */
- if (vect_debug_details (NULL))
- fprintf (dump_file, "mode not supported by target.");
- return NULL_TREE;
- }
-
- return vectype;
-}
-
-
-/* Function vect_align_data_ref.
-
- Handle mislignment of a memory accesses.
-
- FORNOW: Can't handle misaligned accesses.
- Make sure that the dataref is aligned. */
-
-static void
-vect_align_data_ref (tree stmt)
-{
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
-
- /* FORNOW: can't handle misaligned accesses;
- all accesses expected to be aligned. */
- gcc_assert (aligned_access_p (dr));
-}
-
-
-/* Function vect_create_data_ref_ptr.
-
- Create a memory reference expression for vector access, to be used in a
- vector load/store stmt. The reference is based on a new pointer to vector
- type (vp).
-
- Input:
- 1. STMT: a stmt that references memory. Expected to be of the form
- MODIFY_EXPR <name, data-ref> or MODIFY_EXPR <data-ref, name>.
- 2. BSI: block_stmt_iterator where new stmts can be added.
- 3. OFFSET (optional): an offset to be added to the initial address accessed
- by the data-ref in STMT.
- 4. ONLY_INIT: indicate if vp is to be updated in the loop, or remain
- pointing to the initial address.
-
- Output:
- 1. Declare a new ptr to vector_type, and have it point to the base of the
- data reference (initial addressed accessed by the data reference).
- For example, for vector of type V8HI, the following code is generated:
-
- v8hi *vp;
- vp = (v8hi *)initial_address;
-
- if OFFSET is not supplied:
- initial_address = &a[init];
- if OFFSET is supplied:
- initial_address = &a[init + OFFSET];
-
- Return the initial_address in INITIAL_ADDRESS.
-
- 2. Create a data-reference in the loop based on the new vector pointer vp,
- and using a new index variable 'idx' as follows:
-
- vp' = vp + update
-
- where if ONLY_INIT is true:
- update = zero
- and otherwise
- update = idx + vector_type_size
-
- Return the pointer vp'.
-
-
- FORNOW: handle only aligned and consecutive accesses. */
-
-static tree
-vect_create_data_ref_ptr (tree stmt, block_stmt_iterator *bsi, tree offset,
- tree *initial_address, bool only_init)
-{
- tree base_name;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- tree vect_ptr_type;
- tree vect_ptr;
- tree tag;
- v_may_def_optype v_may_defs = STMT_V_MAY_DEF_OPS (stmt);
- v_must_def_optype v_must_defs = STMT_V_MUST_DEF_OPS (stmt);
- vuse_optype vuses = STMT_VUSE_OPS (stmt);
- int nvuses, nv_may_defs, nv_must_defs;
- int i;
- tree new_temp;
- tree vec_stmt;
- tree new_stmt_list = NULL_TREE;
- tree idx;
- edge pe = loop_preheader_edge (loop);
- basic_block new_bb;
- tree vect_ptr_init;
- tree vectype_size;
- tree ptr_update;
- tree data_ref_ptr;
-
- base_name = unshare_expr (DR_BASE_NAME (dr));
- if (vect_debug_details (NULL))
- {
- tree data_ref_base = base_name;
- fprintf (dump_file, "create array_ref of type: ");
- print_generic_expr (dump_file, vectype, TDF_SLIM);
- if (TREE_CODE (data_ref_base) == VAR_DECL)
- fprintf (dump_file, "vectorizing a one dimensional array ref: ");
- else if (TREE_CODE (data_ref_base) == ARRAY_REF)
- fprintf (dump_file, "vectorizing a multidimensional array ref: ");
- else if (TREE_CODE (data_ref_base) == COMPONENT_REF)
- fprintf (dump_file, "vectorizing a record based array ref: ");
- else if (TREE_CODE (data_ref_base) == SSA_NAME)
- fprintf (dump_file, "vectorizing a pointer ref: ");
- print_generic_expr (dump_file, base_name, TDF_SLIM);
- }
-
- /** (1) Create the new vector-pointer variable: **/
-
- vect_ptr_type = build_pointer_type (vectype);
- vect_ptr = vect_get_new_vect_var (vect_ptr_type, vect_pointer_var,
- get_name (base_name));
- add_referenced_tmp_var (vect_ptr);
-
-
- /** (2) Handle aliasing information of the new vector-pointer: **/
-
- tag = STMT_VINFO_MEMTAG (stmt_info);
- gcc_assert (tag);
- get_var_ann (vect_ptr)->type_mem_tag = tag;
-
- /* Mark for renaming all aliased variables
- (i.e, the may-aliases of the type-mem-tag). */
- nvuses = NUM_VUSES (vuses);
- nv_may_defs = NUM_V_MAY_DEFS (v_may_defs);
- nv_must_defs = NUM_V_MUST_DEFS (v_must_defs);
- for (i = 0; i < nvuses; i++)
- {
- tree use = VUSE_OP (vuses, i);
- if (TREE_CODE (use) == SSA_NAME)
- bitmap_set_bit (vars_to_rename, var_ann (SSA_NAME_VAR (use))->uid);
- }
- for (i = 0; i < nv_may_defs; i++)
- {
- tree def = V_MAY_DEF_RESULT (v_may_defs, i);
- if (TREE_CODE (def) == SSA_NAME)
- bitmap_set_bit (vars_to_rename, var_ann (SSA_NAME_VAR (def))->uid);
- }
- for (i = 0; i < nv_must_defs; i++)
- {
- tree def = V_MUST_DEF_RESULT (v_must_defs, i);
- if (TREE_CODE (def) == SSA_NAME)
- bitmap_set_bit (vars_to_rename, var_ann (SSA_NAME_VAR (def))->uid);
- }
-
-
- /** (3) Calculate the initial address the vector-pointer, and set
- the vector-pointer to point to it before the loop: **/
-
- /* Create: (&(base[init_val+offset]) in the loop preheader. */
- new_temp = vect_create_addr_base_for_vector_ref (stmt, &new_stmt_list,
- offset);
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, new_stmt_list);
- gcc_assert (!new_bb);
- *initial_address = new_temp;
-
- /* Create: p = (vectype *) initial_base */
- vec_stmt = fold_convert (vect_ptr_type, new_temp);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, vect_ptr, vec_stmt);
- new_temp = make_ssa_name (vect_ptr, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- new_bb = bsi_insert_on_edge_immediate (pe, vec_stmt);
- gcc_assert (!new_bb);
- vect_ptr_init = TREE_OPERAND (vec_stmt, 0);
-
-
- /** (4) Handle the updating of the vector-pointer inside the loop: **/
-
- if (only_init) /* No update in loop is required. */
- return vect_ptr_init;
-
- idx = vect_create_index_for_vector_ref (loop, bsi);
-
- /* Create: update = idx * vectype_size */
- ptr_update = create_tmp_var (integer_type_node, "update");
- add_referenced_tmp_var (ptr_update);
- vectype_size = build_int_cst (integer_type_node,
- GET_MODE_SIZE (TYPE_MODE (vectype)));
- vec_stmt = build2 (MULT_EXPR, integer_type_node, idx, vectype_size);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, ptr_update, vec_stmt);
- new_temp = make_ssa_name (ptr_update, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- bsi_insert_before (bsi, vec_stmt, BSI_SAME_STMT);
-
- /* Create: data_ref_ptr = vect_ptr_init + update */
- vec_stmt = build2 (PLUS_EXPR, vect_ptr_type, vect_ptr_init, new_temp);
- vec_stmt = build2 (MODIFY_EXPR, void_type_node, vect_ptr, vec_stmt);
- new_temp = make_ssa_name (vect_ptr, vec_stmt);
- TREE_OPERAND (vec_stmt, 0) = new_temp;
- bsi_insert_before (bsi, vec_stmt, BSI_SAME_STMT);
- data_ref_ptr = TREE_OPERAND (vec_stmt, 0);
-
- return data_ref_ptr;
-}
-
-
-/* Function vect_create_destination_var.
-
- Create a new temporary of type VECTYPE. */
-
-static tree
-vect_create_destination_var (tree scalar_dest, tree vectype)
-{
- tree vec_dest;
- const char *new_name;
-
- gcc_assert (TREE_CODE (scalar_dest) == SSA_NAME);
-
- new_name = get_name (scalar_dest);
- if (!new_name)
- new_name = "var_";
- vec_dest = vect_get_new_vect_var (vectype, vect_simple_var, new_name);
- add_referenced_tmp_var (vec_dest);
-
- return vec_dest;
-}
-
-
-/* Function vect_init_vector.
-
- Insert a new stmt (INIT_STMT) that initializes a new vector variable with
- the vector elements of VECTOR_VAR. Return the DEF of INIT_STMT. It will be
- used in the vectorization of STMT. */
-
-static tree
-vect_init_vector (tree stmt, tree vector_var)
-{
- stmt_vec_info stmt_vinfo = vinfo_for_stmt (stmt);
- struct loop *loop = STMT_VINFO_LOOP (stmt_vinfo);
- tree new_var;
- tree init_stmt;
- tree vectype = STMT_VINFO_VECTYPE (stmt_vinfo);
- tree vec_oprnd;
- edge pe;
- tree new_temp;
- basic_block new_bb;
-
- new_var = vect_get_new_vect_var (vectype, vect_simple_var, "cst_");
- add_referenced_tmp_var (new_var);
-
- init_stmt = build2 (MODIFY_EXPR, vectype, new_var, vector_var);
- new_temp = make_ssa_name (new_var, init_stmt);
- TREE_OPERAND (init_stmt, 0) = new_temp;
-
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, init_stmt);
- gcc_assert (!new_bb);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "created new init_stmt: ");
- print_generic_expr (dump_file, init_stmt, TDF_SLIM);
- }
-
- vec_oprnd = TREE_OPERAND (init_stmt, 0);
- return vec_oprnd;
-}
-
-
-/* Function vect_get_vec_def_for_operand.
-
- OP is an operand in STMT. This function returns a (vector) def that will be
- used in the vectorized stmt for STMT.
-
- In the case that OP is an SSA_NAME which is defined in the loop, then
- STMT_VINFO_VEC_STMT of the defining stmt holds the relevant def.
-
- In case OP is an invariant or constant, a new stmt that creates a vector def
- needs to be introduced. */
-
-static tree
-vect_get_vec_def_for_operand (tree op, tree stmt)
-{
- tree vec_oprnd;
- tree vec_stmt;
- tree def_stmt;
- stmt_vec_info def_stmt_info = NULL;
- stmt_vec_info stmt_vinfo = vinfo_for_stmt (stmt);
- tree vectype = STMT_VINFO_VECTYPE (stmt_vinfo);
- int nunits = GET_MODE_NUNITS (TYPE_MODE (vectype));
- struct loop *loop = STMT_VINFO_LOOP (stmt_vinfo);
- basic_block bb;
- tree vec_inv;
- tree t = NULL_TREE;
- tree def;
- int i;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "vect_get_vec_def_for_operand: ");
- print_generic_expr (dump_file, op, TDF_SLIM);
- }
-
- /** ===> Case 1: operand is a constant. **/
-
- if (TREE_CODE (op) == INTEGER_CST || TREE_CODE (op) == REAL_CST)
- {
- /* Create 'vect_cst_ = {cst,cst,...,cst}' */
-
- tree vec_cst;
-
- /* Build a tree with vector elements. */
- if (vect_debug_details (NULL))
- fprintf (dump_file, "Create vector_cst. nunits = %d", nunits);
-
- for (i = nunits - 1; i >= 0; --i)
- {
- t = tree_cons (NULL_TREE, op, t);
- }
- vec_cst = build_vector (vectype, t);
- return vect_init_vector (stmt, vec_cst);
- }
-
- gcc_assert (TREE_CODE (op) == SSA_NAME);
-
- /** ===> Case 2: operand is an SSA_NAME - find the stmt that defines it. **/
-
- def_stmt = SSA_NAME_DEF_STMT (op);
- def_stmt_info = vinfo_for_stmt (def_stmt);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "vect_get_vec_def_for_operand: def_stmt: ");
- print_generic_expr (dump_file, def_stmt, TDF_SLIM);
- }
-
-
- /** ==> Case 2.1: operand is defined inside the loop. **/
-
- if (def_stmt_info)
- {
- /* Get the def from the vectorized stmt. */
-
- vec_stmt = STMT_VINFO_VEC_STMT (def_stmt_info);
- gcc_assert (vec_stmt);
- vec_oprnd = TREE_OPERAND (vec_stmt, 0);
- return vec_oprnd;
- }
-
-
- /** ==> Case 2.2: operand is defined by the loop-header phi-node -
- it is a reduction/induction. **/
-
- bb = bb_for_stmt (def_stmt);
- if (TREE_CODE (def_stmt) == PHI_NODE && flow_bb_inside_loop_p (loop, bb))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "reduction/induction - unsupported.");
- internal_error ("no support for reduction/induction"); /* FORNOW */
- }
-
-
- /** ==> Case 2.3: operand is defined outside the loop -
- it is a loop invariant. */
-
- switch (TREE_CODE (def_stmt))
- {
- case PHI_NODE:
- def = PHI_RESULT (def_stmt);
- break;
- case MODIFY_EXPR:
- def = TREE_OPERAND (def_stmt, 0);
- break;
- case NOP_EXPR:
- def = TREE_OPERAND (def_stmt, 0);
- gcc_assert (IS_EMPTY_STMT (def_stmt));
- def = op;
- break;
- default:
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unsupported defining stmt: ");
- print_generic_expr (dump_file, def_stmt, TDF_SLIM);
- }
- internal_error ("unsupported defining stmt");
- }
-
- /* Build a tree with vector elements. Create 'vec_inv = {inv,inv,..,inv}' */
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "Create vector_inv.");
-
- for (i = nunits - 1; i >= 0; --i)
- {
- t = tree_cons (NULL_TREE, def, t);
- }
-
- vec_inv = build_constructor (vectype, t);
- return vect_init_vector (stmt, vec_inv);
-}
-
-
-/* Function vect_finish_stmt_generation.
-
- Insert a new stmt. */
-
-static void
-vect_finish_stmt_generation (tree stmt, tree vec_stmt, block_stmt_iterator *bsi)
-{
- bsi_insert_before (bsi, vec_stmt, BSI_SAME_STMT);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "add new stmt: ");
- print_generic_expr (dump_file, vec_stmt, TDF_SLIM);
- }
-
- /* Make sure bsi points to the stmt that is being vectorized. */
-
- /* Assumption: any stmts created for the vectorization of stmt S were
- inserted before S. BSI is expected to point to S or some new stmt before S. */
-
- while (stmt != bsi_stmt (*bsi) && !bsi_end_p (*bsi))
- bsi_next (bsi);
- gcc_assert (stmt == bsi_stmt (*bsi));
-}
-
-
-/* Function vectorizable_assignment.
-
- Check if STMT performs an assignment (copy) that can be vectorized.
- If VEC_STMT is also passed, vectorize the STMT: create a vectorized
- stmt to replace it, put it in VEC_STMT, and insert it at BSI.
- Return FALSE if not a vectorizable STMT, TRUE otherwise. */
-
-static bool
-vectorizable_assignment (tree stmt, block_stmt_iterator *bsi, tree *vec_stmt)
-{
- tree vec_dest;
- tree scalar_dest;
- tree op;
- tree vec_oprnd;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- tree new_temp;
-
- /* Is vectorizable assignment? */
-
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- return false;
-
- scalar_dest = TREE_OPERAND (stmt, 0);
- if (TREE_CODE (scalar_dest) != SSA_NAME)
- return false;
-
- op = TREE_OPERAND (stmt, 1);
- if (!vect_is_simple_use (op, loop, NULL))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "use not simple.");
- return false;
- }
-
- if (!vec_stmt) /* transformation not required. */
- {
- STMT_VINFO_TYPE (stmt_info) = assignment_vec_info_type;
- return true;
- }
-
- /** Trasform. **/
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform assignment.");
-
- /* Handle def. */
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
-
- /* Handle use. */
- op = TREE_OPERAND (stmt, 1);
- vec_oprnd = vect_get_vec_def_for_operand (op, stmt);
-
- /* Arguments are ready. create the new vector stmt. */
- *vec_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, vec_oprnd);
- new_temp = make_ssa_name (vec_dest, *vec_stmt);
- TREE_OPERAND (*vec_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, *vec_stmt, bsi);
-
- return true;
-}
-
-
-/* Function vectorizable_operation.
-
- Check if STMT performs a binary or unary operation that can be vectorized.
- If VEC_STMT is also passed, vectorize the STMT: create a vectorized
- stmt to replace it, put it in VEC_STMT, and insert it at BSI.
- Return FALSE if not a vectorizable STMT, TRUE otherwise. */
-
-static bool
-vectorizable_operation (tree stmt, block_stmt_iterator *bsi, tree *vec_stmt)
-{
- tree vec_dest;
- tree scalar_dest;
- tree operation;
- tree op0, op1 = NULL;
- tree vec_oprnd0, vec_oprnd1=NULL;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- int i;
- enum tree_code code;
- enum machine_mode vec_mode;
- tree new_temp;
- int op_type;
- tree op;
- optab optab;
-
- /* Is STMT a vectorizable binary/unary operation? */
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- return false;
-
- if (TREE_CODE (TREE_OPERAND (stmt, 0)) != SSA_NAME)
- return false;
-
- operation = TREE_OPERAND (stmt, 1);
- code = TREE_CODE (operation);
- optab = optab_for_tree_code (code, vectype);
-
- /* Support only unary or binary operations. */
- op_type = TREE_CODE_LENGTH (code);
- if (op_type != unary_op && op_type != binary_op)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "num. args = %d (not unary/binary op).", op_type);
- return false;
- }
-
- for (i = 0; i < op_type; i++)
- {
- op = TREE_OPERAND (operation, i);
- if (!vect_is_simple_use (op, loop, NULL))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "use not simple.");
- return false;
- }
- }
-
- /* Supportable by target? */
- if (!optab)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "no optab.");
- return false;
- }
- vec_mode = TYPE_MODE (vectype);
- if (optab->handlers[(int) vec_mode].insn_code == CODE_FOR_nothing)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "op not supported by target.");
- return false;
- }
-
- if (!vec_stmt) /* transformation not required. */
- {
- STMT_VINFO_TYPE (stmt_info) = op_vec_info_type;
- return true;
- }
-
- /** Transform. **/
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform binary/unary operation.");
-
- /* Handle def. */
- scalar_dest = TREE_OPERAND (stmt, 0);
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
-
- /* Handle uses. */
- op0 = TREE_OPERAND (operation, 0);
- vec_oprnd0 = vect_get_vec_def_for_operand (op0, stmt);
-
- if (op_type == binary_op)
- {
- op1 = TREE_OPERAND (operation, 1);
- vec_oprnd1 = vect_get_vec_def_for_operand (op1, stmt);
- }
-
- /* Arguments are ready. create the new vector stmt. */
-
- if (op_type == binary_op)
- *vec_stmt = build2 (MODIFY_EXPR, vectype, vec_dest,
- build2 (code, vectype, vec_oprnd0, vec_oprnd1));
- else
- *vec_stmt = build2 (MODIFY_EXPR, vectype, vec_dest,
- build1 (code, vectype, vec_oprnd0));
- new_temp = make_ssa_name (vec_dest, *vec_stmt);
- TREE_OPERAND (*vec_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, *vec_stmt, bsi);
-
- return true;
-}
-
-
-/* Function vectorizable_store.
-
- Check if STMT defines a non scalar data-ref (array/pointer/structure) that
- can be vectorized.
- If VEC_STMT is also passed, vectorize the STMT: create a vectorized
- stmt to replace it, put it in VEC_STMT, and insert it at BSI.
- Return FALSE if not a vectorizable STMT, TRUE otherwise. */
-
-static bool
-vectorizable_store (tree stmt, block_stmt_iterator *bsi, tree *vec_stmt)
-{
- tree scalar_dest;
- tree data_ref;
- tree op;
- tree vec_oprnd1;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- enum machine_mode vec_mode;
- tree dummy;
- enum dr_alignment_support alignment_support_cheme;
-
- /* Is vectorizable store? */
-
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- return false;
-
- scalar_dest = TREE_OPERAND (stmt, 0);
- if (TREE_CODE (scalar_dest) != ARRAY_REF
- && TREE_CODE (scalar_dest) != INDIRECT_REF)
- return false;
-
- op = TREE_OPERAND (stmt, 1);
- if (!vect_is_simple_use (op, loop, NULL))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "use not simple.");
- return false;
- }
-
- vec_mode = TYPE_MODE (vectype);
- /* FORNOW. In some cases can vectorize even if data-type not supported
- (e.g. - array initialization with 0). */
- if (mov_optab->handlers[(int)vec_mode].insn_code == CODE_FOR_nothing)
- return false;
-
- if (!STMT_VINFO_DATA_REF (stmt_info))
- return false;
-
-
- if (!vec_stmt) /* transformation not required. */
- {
- STMT_VINFO_TYPE (stmt_info) = store_vec_info_type;
- return true;
- }
-
- /** Trasform. **/
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform store");
-
- alignment_support_cheme = vect_supportable_dr_alignment (dr);
- gcc_assert (alignment_support_cheme);
- gcc_assert (alignment_support_cheme = dr_aligned); /* FORNOW */
-
- /* Handle use - get the vectorized def from the defining stmt. */
- vec_oprnd1 = vect_get_vec_def_for_operand (op, stmt);
-
- /* Handle def. */
- /* FORNOW: make sure the data reference is aligned. */
- vect_align_data_ref (stmt);
- data_ref = vect_create_data_ref_ptr (stmt, bsi, NULL_TREE, &dummy, false);
- data_ref = build_fold_indirect_ref (data_ref);
-
- /* Arguments are ready. create the new vector stmt. */
- *vec_stmt = build2 (MODIFY_EXPR, vectype, data_ref, vec_oprnd1);
- vect_finish_stmt_generation (stmt, *vec_stmt, bsi);
-
- return true;
-}
-
-
-/* vectorizable_load.
-
- Check if STMT reads a non scalar data-ref (array/pointer/structure) that
- can be vectorized.
- If VEC_STMT is also passed, vectorize the STMT: create a vectorized
- stmt to replace it, put it in VEC_STMT, and insert it at BSI.
- Return FALSE if not a vectorizable STMT, TRUE otherwise. */
-
-static bool
-vectorizable_load (tree stmt, block_stmt_iterator *bsi, tree *vec_stmt)
-{
- tree scalar_dest;
- tree vec_dest = NULL;
- tree data_ref = NULL;
- tree op;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info);
- tree vectype = STMT_VINFO_VECTYPE (stmt_info);
- tree new_temp;
- int mode;
- tree init_addr;
- tree new_stmt;
- tree dummy;
- basic_block new_bb;
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- edge pe = loop_preheader_edge (loop);
- enum dr_alignment_support alignment_support_cheme;
-
- /* Is vectorizable load? */
-
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- return false;
-
- scalar_dest = TREE_OPERAND (stmt, 0);
- if (TREE_CODE (scalar_dest) != SSA_NAME)
- return false;
-
- op = TREE_OPERAND (stmt, 1);
- if (TREE_CODE (op) != ARRAY_REF && TREE_CODE (op) != INDIRECT_REF)
- return false;
-
- if (!STMT_VINFO_DATA_REF (stmt_info))
- return false;
-
- mode = (int) TYPE_MODE (vectype);
-
- /* FORNOW. In some cases can vectorize even if data-type not supported
- (e.g. - data copies). */
- if (mov_optab->handlers[mode].insn_code == CODE_FOR_nothing)
- {
- if (vect_debug_details (loop))
- fprintf (dump_file, "Aligned load, but unsupported type.");
- return false;
- }
-
- if (!vec_stmt) /* transformation not required. */
- {
- STMT_VINFO_TYPE (stmt_info) = load_vec_info_type;
- return true;
- }
-
- /** Trasform. **/
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform load.");
-
- alignment_support_cheme = vect_supportable_dr_alignment (dr);
- gcc_assert (alignment_support_cheme);
-
- if (alignment_support_cheme == dr_aligned
- || alignment_support_cheme == dr_unaligned_supported)
- {
- /* Create:
- p = initial_addr;
- indx = 0;
- loop {
- vec_dest = *(p);
- indx = indx + 1;
- }
- */
-
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- data_ref = vect_create_data_ref_ptr (stmt, bsi, NULL_TREE, &dummy, false);
- if (aligned_access_p (dr))
- data_ref = build_fold_indirect_ref (data_ref);
- else
- {
- int mis = DR_MISALIGNMENT (dr);
- tree tmis = (mis == -1 ?
- integer_zero_node :
- build_int_cst (integer_type_node, mis));
- tmis = int_const_binop (MULT_EXPR, tmis,
- build_int_cst (integer_type_node, BITS_PER_UNIT), 1);
- data_ref = build2 (MISALIGNED_INDIRECT_REF, vectype, data_ref, tmis);
- }
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, data_ref);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, new_stmt, bsi);
- }
- else if (alignment_support_cheme == dr_unaligned_software_pipeline)
- {
- /* Create:
- p1 = initial_addr;
- msq_init = *(floor(p1))
- p2 = initial_addr + VS - 1;
- magic = have_builtin ? builtin_result : initial_address;
- indx = 0;
- loop {
- p2' = p2 + indx * vectype_size
- lsq = *(floor(p2'))
- vec_dest = realign_load (msq, lsq, magic)
- indx = indx + 1;
- msq = lsq;
- }
- */
-
- tree offset;
- tree magic;
- tree phi_stmt;
- tree msq_init;
- tree msq, lsq;
- tree dataref_ptr;
- tree params;
-
- /* <1> Create msq_init = *(floor(p1)) in the loop preheader */
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- data_ref = vect_create_data_ref_ptr (stmt, bsi, NULL_TREE,
- &init_addr, true);
- data_ref = build1 (ALIGN_INDIRECT_REF, vectype, data_ref);
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, data_ref);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- new_bb = bsi_insert_on_edge_immediate (pe, new_stmt);
- gcc_assert (!new_bb);
- msq_init = TREE_OPERAND (new_stmt, 0);
-
-
- /* <2> Create lsq = *(floor(p2')) in the loop */
- offset = build_int_cst (integer_type_node,
- GET_MODE_NUNITS (TYPE_MODE (vectype)));
- offset = int_const_binop (MINUS_EXPR, offset, integer_one_node, 1);
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- dataref_ptr = vect_create_data_ref_ptr (stmt, bsi, offset, &dummy, false);
- data_ref = build1 (ALIGN_INDIRECT_REF, vectype, dataref_ptr);
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, data_ref);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, new_stmt, bsi);
- lsq = TREE_OPERAND (new_stmt, 0);
-
-
- /* <3> */
- if (targetm.vectorize.builtin_mask_for_load)
- {
- /* Create permutation mask, if required, in loop preheader. */
- tree builtin_decl;
- params = build_tree_list (NULL_TREE, init_addr);
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- builtin_decl = targetm.vectorize.builtin_mask_for_load ();
- new_stmt = build_function_call_expr (builtin_decl, params);
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, new_stmt);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- new_bb = bsi_insert_on_edge_immediate (pe, new_stmt);
- gcc_assert (!new_bb);
- magic = TREE_OPERAND (new_stmt, 0);
- }
- else
- {
- /* Use current address instead of init_addr for reduced reg pressure.
- */
- magic = dataref_ptr;
- }
-
-
- /* <4> Create msq = phi <msq_init, lsq> in loop */
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- msq = make_ssa_name (vec_dest, NULL_TREE);
- phi_stmt = create_phi_node (msq, loop->header); /* CHECKME */
- SSA_NAME_DEF_STMT (msq) = phi_stmt;
- add_phi_arg (&phi_stmt, msq_init, loop_preheader_edge (loop));
- add_phi_arg (&phi_stmt, lsq, loop_latch_edge (loop));
-
-
- /* <5> Create <vec_dest = realign_load (msq, lsq, magic)> in loop */
- vec_dest = vect_create_destination_var (scalar_dest, vectype);
- new_stmt = build3 (REALIGN_LOAD_EXPR, vectype, msq, lsq, magic);
- new_stmt = build2 (MODIFY_EXPR, vectype, vec_dest, new_stmt);
- new_temp = make_ssa_name (vec_dest, new_stmt);
- TREE_OPERAND (new_stmt, 0) = new_temp;
- vect_finish_stmt_generation (stmt, new_stmt, bsi);
- }
- else
- gcc_unreachable ();
-
- *vec_stmt = new_stmt;
- return true;
-}
-
-
-/* Function vect_supportable_dr_alignment
-
- Return whether the data reference DR is supported with respect to its
- alignment. */
-
-static enum dr_alignment_support
-vect_supportable_dr_alignment (struct data_reference *dr)
-{
- tree vectype = STMT_VINFO_VECTYPE (vinfo_for_stmt (DR_STMT (dr)));
- enum machine_mode mode = (int) TYPE_MODE (vectype);
-
- if (aligned_access_p (dr))
- return dr_aligned;
-
- /* Possibly unaligned access. */
-
- if (DR_IS_READ (dr))
- {
- if (vec_realign_load_optab->handlers[mode].insn_code != CODE_FOR_nothing
- && (!targetm.vectorize.builtin_mask_for_load
- || targetm.vectorize.builtin_mask_for_load ()))
- return dr_unaligned_software_pipeline;
-
- if (targetm.vectorize.misaligned_mem_ok (mode))
- /* Can't software pipeline the loads. */
- return dr_unaligned_supported;
- }
-
- /* Unsupported. */
- return dr_unaligned_unsupported;
-}
-
-
-/* Function vect_transform_stmt.
-
- Create a vectorized stmt to replace STMT, and insert it at BSI. */
-
-static bool
-vect_transform_stmt (tree stmt, block_stmt_iterator *bsi)
-{
- bool is_store = false;
- tree vec_stmt = NULL_TREE;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- bool done;
-
- switch (STMT_VINFO_TYPE (stmt_info))
- {
- case op_vec_info_type:
- done = vectorizable_operation (stmt, bsi, &vec_stmt);
- gcc_assert (done);
- break;
-
- case assignment_vec_info_type:
- done = vectorizable_assignment (stmt, bsi, &vec_stmt);
- gcc_assert (done);
- break;
-
- case load_vec_info_type:
- done = vectorizable_load (stmt, bsi, &vec_stmt);
- gcc_assert (done);
- break;
-
- case store_vec_info_type:
- done = vectorizable_store (stmt, bsi, &vec_stmt);
- gcc_assert (done);
- is_store = true;
- break;
- default:
- if (vect_debug_details (NULL))
- fprintf (dump_file, "stmt not supported.");
- gcc_unreachable ();
- }
-
- STMT_VINFO_VEC_STMT (stmt_info) = vec_stmt;
-
- return is_store;
-}
-
-
-/* This function builds ni_name = number of iterations loop executes
- on the loop preheader. */
-
-static tree
-vect_build_loop_niters (loop_vec_info loop_vinfo)
-{
- tree ni_name, stmt, var;
- edge pe;
- basic_block new_bb = NULL;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- tree ni = unshare_expr (LOOP_VINFO_NITERS(loop_vinfo));
-
- var = create_tmp_var (TREE_TYPE (ni), "niters");
- add_referenced_tmp_var (var);
- if (TREE_CODE (ni) == INTEGER_CST)
- {
- /* This case is generated when treating a known loop bound
- indivisible by VF. Here we cannot use force_gimple_operand. */
- stmt = build (MODIFY_EXPR, void_type_node, var, ni);
- ni_name = make_ssa_name (var, stmt);
- TREE_OPERAND (stmt, 0) = ni_name;
- }
- else
- ni_name = force_gimple_operand (ni, &stmt, false, var);
-
- pe = loop_preheader_edge (loop);
- if (stmt)
- new_bb = bsi_insert_on_edge_immediate (pe, stmt);
- if (new_bb)
- add_bb_to_loop (new_bb, EDGE_PRED (new_bb, 0)->src->loop_father);
-
- return ni_name;
-}
-
-
-/* This function generates the following statements:
-
- ni_name = number of iterations loop executes
- ratio = ni_name / vf
- ratio_mult_vf_name = ratio * vf
-
- and places them at the loop preheader edge. */
-
-static void
-vect_generate_tmps_on_preheader (loop_vec_info loop_vinfo, tree *ni_name_p,
- tree *ratio_mult_vf_name_p, tree *ratio_p)
-{
-
- edge pe;
- basic_block new_bb;
- tree stmt, ni_name;
- tree ratio;
- tree ratio_mult_vf_name, ratio_mult_vf;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- tree ni = LOOP_VINFO_NITERS(loop_vinfo);
-
- int vf, i;
-
- /* Generate temporary variable that contains
- number of iterations loop executes. */
-
- ni_name = vect_build_loop_niters (loop_vinfo);
-
- /* ratio = ni / vf.
- vf is power of 2; then if ratio = = n >> log2 (vf). */
- vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
- ratio = vect_build_symbol_bound (ni_name, vf, loop);
-
- /* Update initial conditions of loop copy. */
-
- /* ratio_mult_vf = ratio * vf;
- then if ratio_mult_vf = ratio << log2 (vf). */
-
- i = exact_log2 (vf);
- ratio_mult_vf = create_tmp_var (TREE_TYPE (ni), "ratio_mult_vf");
- add_referenced_tmp_var (ratio_mult_vf);
-
- ratio_mult_vf_name = make_ssa_name (ratio_mult_vf, NULL_TREE);
-
- stmt = build2 (MODIFY_EXPR, void_type_node, ratio_mult_vf_name,
- build2 (LSHIFT_EXPR, TREE_TYPE (ratio),
- ratio, build_int_cst (unsigned_type_node,
- i)));
-
- SSA_NAME_DEF_STMT (ratio_mult_vf_name) = stmt;
-
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, stmt);
- if (new_bb)
- add_bb_to_loop (new_bb, EDGE_PRED (new_bb, 0)->src->loop_father);
-
- *ni_name_p = ni_name;
- *ratio_mult_vf_name_p = ratio_mult_vf_name;
- *ratio_p = ratio;
-
- return;
-}
-
-
-/* This function generates stmt
-
- tmp = n / vf;
-
- and attaches it to preheader of LOOP. */
-
-static tree
-vect_build_symbol_bound (tree n, int vf, struct loop * loop)
-{
- tree var, stmt, var_name;
- edge pe;
- basic_block new_bb;
- int i;
-
- /* create temporary variable */
- var = create_tmp_var (TREE_TYPE (n), "bnd");
- add_referenced_tmp_var (var);
-
- var_name = make_ssa_name (var, NULL_TREE);
-
- /* vf is power of 2; then n/vf = n >> log2 (vf). */
-
- i = exact_log2 (vf);
- stmt = build2 (MODIFY_EXPR, void_type_node, var_name,
- build2 (RSHIFT_EXPR, TREE_TYPE (n),
- n, build_int_cst (unsigned_type_node,i)));
-
- SSA_NAME_DEF_STMT (var_name) = stmt;
-
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, stmt);
- if (new_bb)
- add_bb_to_loop (new_bb, EDGE_PRED (new_bb, 0)->src->loop_father);
- else
- if (vect_debug_details (NULL))
- fprintf (dump_file, "New bb on preheader edge was not generated.");
-
- return var_name;
-}
-
-
-/* Function vect_transform_loop_bound.
-
- Create a new exit condition for the loop. */
-
-static void
-vect_transform_loop_bound (loop_vec_info loop_vinfo, tree niters)
-{
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- edge exit_edge = loop->single_exit;
- block_stmt_iterator loop_exit_bsi = bsi_last (exit_edge->src);
- tree indx_before_incr, indx_after_incr;
- tree orig_cond_expr;
- HOST_WIDE_INT old_N = 0;
- int vf;
- tree cond_stmt;
- tree new_loop_bound;
- bool symbol_niters;
- tree cond;
- tree lb_type;
-
- symbol_niters = !LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo);
-
- if (!symbol_niters)
- old_N = LOOP_VINFO_INT_NITERS (loop_vinfo);
-
- vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
-
- orig_cond_expr = LOOP_VINFO_EXIT_COND (loop_vinfo);
-#ifdef ENABLE_CHECKING
- gcc_assert (orig_cond_expr);
-#endif
- gcc_assert (orig_cond_expr == bsi_stmt (loop_exit_bsi));
-
- create_iv (integer_zero_node, integer_one_node, NULL_TREE, loop,
- &loop_exit_bsi, false, &indx_before_incr, &indx_after_incr);
-
- /* bsi_insert is using BSI_NEW_STMT. We need to bump it back
- to point to the exit condition. */
- bsi_next (&loop_exit_bsi);
- gcc_assert (bsi_stmt (loop_exit_bsi) == orig_cond_expr);
-
- /* new loop exit test: */
- lb_type = TREE_TYPE (TREE_OPERAND (COND_EXPR_COND (orig_cond_expr), 1));
- if (!symbol_niters)
- new_loop_bound = fold_convert (lb_type,
- build_int_cst (unsigned_type_node,
- old_N/vf));
- else
- new_loop_bound = niters;
-
- if (exit_edge->flags & EDGE_TRUE_VALUE) /* 'then' edge exits the loop. */
- cond = build2 (GE_EXPR, boolean_type_node,
- indx_after_incr, new_loop_bound);
- else /* 'then' edge loops back. */
- cond = build2 (LT_EXPR, boolean_type_node,
- indx_after_incr, new_loop_bound);
-
- cond_stmt = build3 (COND_EXPR, TREE_TYPE (orig_cond_expr), cond,
- COND_EXPR_THEN (orig_cond_expr),
- COND_EXPR_ELSE (orig_cond_expr));
-
- bsi_insert_before (&loop_exit_bsi, cond_stmt, BSI_SAME_STMT);
-
- /* remove old loop exit test: */
- bsi_remove (&loop_exit_bsi);
-
- if (vect_debug_details (NULL))
- print_generic_expr (dump_file, cond_stmt, TDF_SLIM);
-
- loop->nb_iterations = new_loop_bound;
-}
-
-
-/* Function vect_update_ivs_after_vectorizer.
-
- "Advance" the induction variables of LOOP to the value they should take
- after the execution of LOOP. This is currently necessary because the
- vectorizer does not handle induction variables that are used after the
- loop. Such a situation occurs when the last iterations of LOOP are
- peeled, because:
- 1. We introduced new uses after LOOP for IVs that were not originally used
- after LOOP: the IVs of LOOP are now used by an epilog loop.
- 2. LOOP is going to be vectorized; this means that it will iterate N/VF
- times, whereas the loop IVs should be bumped N times.
-
- Input:
- - LOOP - a loop that is going to be vectorized. The last few iterations
- of LOOP were peeled.
- - NITERS - the number of iterations that LOOP executes (before it is
- vectorized). i.e, the number of times the ivs should be bumped.
-
- We have:
-
- bb_before_loop:
- if (guard-cond) GOTO bb_before_epilog_loop
- else GOTO loop
-
- loop:
- do {
- } while ...
-
- bb_before_epilog_loop:
-
- bb_before_epilog_loop has edges coming in form the loop exit and
- from bb_before_loop. New definitions for ivs will be placed on the edge
- from loop->exit to bb_before_epilog_loop. This also requires that we update
- the phis in bb_before_epilog_loop. (In the code this bb is denoted
- "update_bb").
-
- Assumption 1: Like the rest of the vectorizer, this function assumes
- a single loop exit that has a single predecessor.
-
- Assumption 2: The phi nodes in the LOOP header and in update_bb are
- organized in the same order.
-
- Assumption 3: The access function of the ivs is simple enough (see
- vect_can_advance_ivs_p). This assumption will be relaxed in the future.
- */
-
-static void
-vect_update_ivs_after_vectorizer (struct loop *loop, tree niters)
-{
- edge exit = loop->exit_edges[0];
- tree phi, phi1;
- basic_block update_bb = exit->dest;
- edge update_e;
-
- /* Generate basic block at the exit from the loop. */
- basic_block new_bb = split_edge (exit);
-
- add_bb_to_loop (new_bb, EDGE_SUCC (new_bb, 0)->dest->loop_father);
- loop->exit_edges[0] = EDGE_PRED (new_bb, 0);
- update_e = EDGE_SUCC (new_bb, 0);
-
- for (phi = phi_nodes (loop->header), phi1 = phi_nodes (update_bb);
- phi && phi1;
- phi = PHI_CHAIN (phi), phi1 = PHI_CHAIN (phi1))
- {
- tree access_fn = NULL;
- tree evolution_part;
- tree init_expr;
- tree step_expr;
- tree var, stmt, ni, ni_name;
- block_stmt_iterator last_bsi;
-
- /* Skip virtual phi's. The data dependences that are associated with
- virtual defs/uses (i.e., memory accesses) are analyzed elsewhere. */
-
- if (!is_gimple_reg (SSA_NAME_VAR (PHI_RESULT (phi))))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "virtual phi. skip.");
- continue;
- }
-
- access_fn = analyze_scalar_evolution (loop, PHI_RESULT (phi));
- gcc_assert (access_fn);
- evolution_part =
- unshare_expr (evolution_part_in_loop_num (access_fn, loop->num));
-
- /* FORNOW: We do not transform initial conditions of IVs
- which evolution functions are a polynomial of degree >= 2 or
- exponential. */
- gcc_assert (!tree_is_chrec (evolution_part));
-
- step_expr = evolution_part;
- init_expr = unshare_expr (initial_condition (access_fn));
-
- ni = build2 (PLUS_EXPR, TREE_TYPE (init_expr),
- build2 (MULT_EXPR, TREE_TYPE (niters),
- niters, step_expr), init_expr);
-
- var = create_tmp_var (TREE_TYPE (init_expr), "tmp");
- add_referenced_tmp_var (var);
-
- ni_name = force_gimple_operand (ni, &stmt, false, var);
-
- /* Insert stmt into new_bb. */
- last_bsi = bsi_last (new_bb);
- if (stmt)
- bsi_insert_after (&last_bsi, stmt, BSI_NEW_STMT);
-
- /* Fix phi expressions in duplicated loop. */
- gcc_assert (PHI_ARG_DEF_FROM_EDGE (phi1, update_e) ==
- PHI_ARG_DEF_FROM_EDGE (phi, EDGE_SUCC (loop->latch, 0)));
- SET_PHI_ARG_DEF (phi1, phi_arg_from_edge (phi1, update_e), ni_name);
- }
-}
-
-
-/* This function is the main driver of transformation
- to be done for loop before vectorizing it in case of
- unknown loop bound. */
-
-static void
-vect_transform_for_unknown_loop_bound (loop_vec_info loop_vinfo, tree * ratio,
- struct loops *loops)
-{
-
- tree ni_name, ratio_mult_vf_name;
-#ifdef ENABLE_CHECKING
- int loop_num;
-#endif
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- struct loop *new_loop;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_transtorm_for_unknown_loop_bound>>\n");
-
- /* Generate the following variables on the preheader of original loop:
-
- ni_name = number of iteration the original loop executes
- ratio = ni_name / vf
- ratio_mult_vf_name = ratio * vf */
- vect_generate_tmps_on_preheader (loop_vinfo, &ni_name,
- &ratio_mult_vf_name, ratio);
-
- /* Update loop info. */
- loop->pre_header = loop_preheader_edge (loop)->src;
- loop->pre_header_edges[0] = loop_preheader_edge (loop);
-
-#ifdef ENABLE_CHECKING
- loop_num = loop->num;
-#endif
- new_loop = slpeel_tree_peel_loop_to_edge (loop, loops, loop->exit_edges[0],
- ratio_mult_vf_name, ni_name, true);
-#ifdef ENABLE_CHECKING
- gcc_assert (new_loop);
- gcc_assert (loop_num == loop->num);
-#endif
-
- /* Update IVs of original loop as if they were advanced
- by ratio_mult_vf_name steps. */
-
-#ifdef ENABLE_CHECKING
- /* Check existence of intermediate bb. */
- gcc_assert (loop->exit_edges[0]->dest == new_loop->pre_header);
-#endif
- vect_update_ivs_after_vectorizer (loop, ratio_mult_vf_name);
-
- return;
-
-}
-
-
-/* Function vect_gen_niters_for_prolog_loop
-
- Set the number of iterations for the loop represented by LOOP_VINFO
- to the minimum between NITERS (the original iteration count of the loop)
- and the misalignment of DR - the first data reference recorded in
- LOOP_VINFO_UNALIGNED_DR (LOOP_VINFO). As a result, after the execution of
- this loop, the data reference DR will refer to an aligned location. */
-
-static tree
-vect_gen_niters_for_prolog_loop (loop_vec_info loop_vinfo, tree niters)
-{
- struct data_reference *dr = LOOP_VINFO_UNALIGNED_DR (loop_vinfo);
- int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- tree var, stmt;
- tree iters, iters_name;
- edge pe;
- basic_block new_bb;
- tree dr_stmt = DR_STMT (dr);
- stmt_vec_info stmt_info = vinfo_for_stmt (dr_stmt);
- tree start_addr, byte_miss_align, elem_miss_align;
- int vec_type_align =
- GET_MODE_ALIGNMENT (TYPE_MODE (STMT_VINFO_VECTYPE (stmt_info)))
- / BITS_PER_UNIT;
- tree tmp1, tmp2;
- tree new_stmt_list = NULL_TREE;
-
- start_addr = vect_create_addr_base_for_vector_ref (dr_stmt,
- &new_stmt_list, NULL_TREE);
-
- pe = loop_preheader_edge (loop);
- new_bb = bsi_insert_on_edge_immediate (pe, new_stmt_list);
- if (new_bb)
- add_bb_to_loop (new_bb, EDGE_PRED (new_bb, 0)->src->loop_father);
-
- byte_miss_align =
- build (BIT_AND_EXPR, integer_type_node, start_addr,
- build (MINUS_EXPR, integer_type_node,
- build_int_cst (unsigned_type_node,
- vec_type_align), integer_one_node));
- tmp1 = build_int_cst (unsigned_type_node, vec_type_align/vf);
- elem_miss_align = build (FLOOR_DIV_EXPR, integer_type_node,
- byte_miss_align, tmp1);
-
- tmp2 =
- build (BIT_AND_EXPR, integer_type_node,
- build (MINUS_EXPR, integer_type_node,
- build_int_cst (unsigned_type_node, vf), elem_miss_align),
- build (MINUS_EXPR, integer_type_node,
- build_int_cst (unsigned_type_node, vf), integer_one_node));
-
- iters = build2 (MIN_EXPR, TREE_TYPE (tmp2), tmp2, niters);
- var = create_tmp_var (TREE_TYPE (iters), "iters");
- add_referenced_tmp_var (var);
- iters_name = force_gimple_operand (iters, &stmt, false, var);
-
- /* Insert stmt on loop preheader edge. */
- pe = loop_preheader_edge (loop);
- if (stmt)
- new_bb = bsi_insert_on_edge_immediate (pe, stmt);
- if (new_bb)
- add_bb_to_loop (new_bb, EDGE_PRED (new_bb, 0)->src->loop_father);
-
- return iters_name;
-}
-
-
-/* Function vect_update_niters_after_peeling
-
- NITERS iterations were peeled from the loop represented by LOOP_VINFO.
- The new number of iterations is therefore original_niters - NITERS.
- Record the new number of iterations in LOOP_VINFO. */
-
-static void
-vect_update_niters_after_peeling (loop_vec_info loop_vinfo, tree niters)
-{
- tree n_iters = LOOP_VINFO_NITERS (loop_vinfo);
- LOOP_VINFO_NITERS (loop_vinfo) =
- build (MINUS_EXPR, integer_type_node, n_iters, niters);
-}
-
-
-/* Function vect_update_inits_of_dr
-
- NITERS iterations were peeled from LOOP. DR represents a data reference
- in LOOP. This function updates the information recorded in DR to
- account for the fact that the first NITERS iterations had already been
- executed. Specifically, it updates the initial_condition of the
- access_function of DR. */
-
-static void
-vect_update_inits_of_dr (struct data_reference *dr, struct loop *loop,
- tree niters)
-{
- tree access_fn = DR_ACCESS_FN (dr, 0);
- tree init, init_new, step;
-
- step = evolution_part_in_loop_num (access_fn, loop->num);
- init = initial_condition (access_fn);
-
- init_new = build (PLUS_EXPR, TREE_TYPE (init),
- build (MULT_EXPR, TREE_TYPE (niters),
- niters, step), init);
- DR_ACCESS_FN (dr, 0) = chrec_replace_initial_condition (access_fn, init_new);
-
- return;
-}
-
-
-/* Function vect_update_inits_of_drs
-
- NITERS iterations were peeled from the loop represented by LOOP_VINFO.
- This function updates the information recorded for the data references in
- the loop to account for the fact that the first NITERS iterations had
- already been executed. Specifically, it updates the initial_condition of the
- access_function of all the data_references in the loop. */
-
-static void
-vect_update_inits_of_drs (loop_vec_info loop_vinfo, tree niters)
-{
- unsigned int i;
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
-
- if (dump_file && (dump_flags & TDF_DETAILS))
- fprintf (dump_file, "\n<<vect_update_inits_of_dr>>\n");
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- vect_update_inits_of_dr (dr, loop, niters);
- }
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- vect_update_inits_of_dr (dr, loop, niters);
- }
-}
-
-
-/* Function vect_do_peeling_for_alignment
-
- Peel the first 'niters' iterations of the loop represented by LOOP_VINFO.
- 'niters' is set to the misalignment of one of the data references in the
- loop, thereby forcing it to refer to an aligned location at the beginning
- of the execution of this loop. The data reference for which we are
- peeling is recorded in LOOP_VINFO_UNALIGNED_DR. */
-
-static void
-vect_do_peeling_for_alignment (loop_vec_info loop_vinfo, struct loops *loops)
-{
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- tree niters_of_prolog_loop, ni_name;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_do_peeling_for_alignment>>\n");
-
- ni_name = vect_build_loop_niters (loop_vinfo);
- niters_of_prolog_loop = vect_gen_niters_for_prolog_loop (loop_vinfo, ni_name);
-
-
- /* Peel the prolog loop and iterate it niters_of_prolog_loop. */
- slpeel_tree_peel_loop_to_edge (loop, loops, loop_preheader_edge(loop),
- niters_of_prolog_loop, ni_name, false);
-
- /* Update number of times loop executes. */
- vect_update_niters_after_peeling (loop_vinfo, niters_of_prolog_loop);
-
- /* Update all inits of access functions of all data refs. */
- vect_update_inits_of_drs (loop_vinfo, niters_of_prolog_loop);
-
- /* After peeling we have to reset scalar evolution analyzer. */
- scev_reset ();
-
- return;
-}
-
-
-/* Function vect_transform_loop.
-
- The analysis phase has determined that the loop is vectorizable.
- Vectorize the loop - created vectorized stmts to replace the scalar
- stmts in the loop, and update the loop exit condition. */
-
-static void
-vect_transform_loop (loop_vec_info loop_vinfo,
- struct loops *loops ATTRIBUTE_UNUSED)
-{
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
- int nbbs = loop->num_nodes;
- block_stmt_iterator si;
- int i;
- tree ratio = NULL;
- int vectorization_factor = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vec_transform_loop>>\n");
-
-
- /* Peel the loop if there are data refs with unknown alignment.
- Only one data ref with unknown store is allowed. */
-
-
- if (LOOP_DO_PEELING_FOR_ALIGNMENT (loop_vinfo))
- vect_do_peeling_for_alignment (loop_vinfo, loops);
-
- /* If the loop has a symbolic number of iterations 'n'
- (i.e. it's not a compile time constant),
- then an epilog loop needs to be created. We therefore duplicate
- the initial loop. The original loop will be vectorized, and will compute
- the first (n/VF) iterations. The second copy of the loop will remain
- serial and will compute the remaining (n%VF) iterations.
- (VF is the vectorization factor). */
-
- if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo))
- vect_transform_for_unknown_loop_bound (loop_vinfo, &ratio, loops);
-
- /* FORNOW: we'll treat the case where niters is constant and
-
- niters % vf != 0
-
- in the way similar to one with symbolic niters.
- For this we'll generate variable which value is equal to niters. */
-
- if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
- && (LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0))
- vect_transform_for_unknown_loop_bound (loop_vinfo, &ratio, loops);
-
-
- /* 1) Make sure the loop header has exactly two entries
- 2) Make sure we have a preheader basic block. */
-
- gcc_assert (EDGE_COUNT (loop->header->preds) == 2);
-
- loop_split_edge_with (loop_preheader_edge (loop), NULL);
-
-
- /* FORNOW: the vectorizer supports only loops which body consist
- of one basic block (header + empty latch). When the vectorizer will
- support more involved loop forms, the order by which the BBs are
- traversed need to be reconsidered. */
-
- for (i = 0; i < nbbs; i++)
- {
- basic_block bb = bbs[i];
-
- for (si = bsi_start (bb); !bsi_end_p (si);)
- {
- tree stmt = bsi_stmt (si);
- stmt_vec_info stmt_info;
- bool is_store;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "------>vectorizing statement: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- stmt_info = vinfo_for_stmt (stmt);
- gcc_assert (stmt_info);
- if (!STMT_VINFO_RELEVANT_P (stmt_info))
- {
- bsi_next (&si);
- continue;
- }
-#ifdef ENABLE_CHECKING
- /* FORNOW: Verify that all stmts operate on the same number of
- units and no inner unrolling is necessary. */
- gcc_assert
- (GET_MODE_NUNITS (TYPE_MODE (STMT_VINFO_VECTYPE (stmt_info)))
- == vectorization_factor);
-#endif
- /* -------- vectorize statement ------------ */
- if (vect_debug_details (NULL))
- fprintf (dump_file, "transform statement.");
-
- is_store = vect_transform_stmt (stmt, &si);
- if (is_store)
- {
- /* free the attached stmt_vec_info and remove the stmt. */
- stmt_ann_t ann = stmt_ann (stmt);
- free (stmt_info);
- set_stmt_info (ann, NULL);
- bsi_remove (&si);
- continue;
- }
-
- bsi_next (&si);
- } /* stmts in BB */
- } /* BBs in loop */
-
- vect_transform_loop_bound (loop_vinfo, ratio);
-
- if (vect_debug_details (loop))
- fprintf (dump_file,"Success! loop vectorized.");
- if (vect_debug_stats (loop))
- fprintf (dump_file, "LOOP VECTORIZED.");
-}
-
-
-/* Function vect_is_simple_use.
-
- Input:
- LOOP - the loop that is being vectorized.
- OPERAND - operand of a stmt in LOOP.
- DEF - the defining stmt in case OPERAND is an SSA_NAME.
-
- Returns whether a stmt with OPERAND can be vectorized.
- Supportable operands are constants, loop invariants, and operands that are
- defined by the current iteration of the loop. Unsupportable operands are
- those that are defined by a previous iteration of the loop (as is the case
- in reduction/induction computations). */
-
-static bool
-vect_is_simple_use (tree operand, struct loop *loop, tree *def)
-{
- tree def_stmt;
- basic_block bb;
-
- if (def)
- *def = NULL_TREE;
-
- if (TREE_CODE (operand) == INTEGER_CST || TREE_CODE (operand) == REAL_CST)
- return true;
-
- if (TREE_CODE (operand) != SSA_NAME)
- return false;
-
- def_stmt = SSA_NAME_DEF_STMT (operand);
- if (def_stmt == NULL_TREE )
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "no def_stmt.");
- return false;
- }
-
- /* empty stmt is expected only in case of a function argument.
- (Otherwise - we expect a phi_node or a modify_expr). */
- if (IS_EMPTY_STMT (def_stmt))
- {
- tree arg = TREE_OPERAND (def_stmt, 0);
- if (TREE_CODE (arg) == INTEGER_CST || TREE_CODE (arg) == REAL_CST)
- return true;
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Unexpected empty stmt: ");
- print_generic_expr (dump_file, def_stmt, TDF_SLIM);
- }
- return false;
- }
-
- /* phi_node inside the loop indicates an induction/reduction pattern.
- This is not supported yet. */
- bb = bb_for_stmt (def_stmt);
- if (TREE_CODE (def_stmt) == PHI_NODE && flow_bb_inside_loop_p (loop, bb))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "reduction/induction - unsupported.");
- return false; /* FORNOW: not supported yet. */
- }
-
- /* Expecting a modify_expr or a phi_node. */
- if (TREE_CODE (def_stmt) == MODIFY_EXPR
- || TREE_CODE (def_stmt) == PHI_NODE)
- {
- if (def)
- *def = def_stmt;
- return true;
- }
-
- return false;
-}
-
-
-/* Function vect_analyze_operations.
-
- Scan the loop stmts and make sure they are all vectorizable. */
-
-static bool
-vect_analyze_operations (loop_vec_info loop_vinfo)
-{
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
- int nbbs = loop->num_nodes;
- block_stmt_iterator si;
- int vectorization_factor = 0;
- int i;
- bool ok;
- tree scalar_type;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_operations>>\n");
-
- for (i = 0; i < nbbs; i++)
- {
- basic_block bb = bbs[i];
-
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- tree stmt = bsi_stmt (si);
- int nunits;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree vectype;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "==> examining statement: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
-
- gcc_assert (stmt_info);
-
- /* skip stmts which do not need to be vectorized.
- this is expected to include:
- - the COND_EXPR which is the loop exit condition
- - any LABEL_EXPRs in the loop
- - computations that are used only for array indexing or loop
- control */
-
- if (!STMT_VINFO_RELEVANT_P (stmt_info))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "irrelevant.");
- continue;
- }
-
- if (VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: vector stmt in loop:");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- if (STMT_VINFO_DATA_REF (stmt_info))
- scalar_type = TREE_TYPE (DR_REF (STMT_VINFO_DATA_REF (stmt_info)));
- else if (TREE_CODE (stmt) == MODIFY_EXPR)
- scalar_type = TREE_TYPE (TREE_OPERAND (stmt, 0));
- else
- scalar_type = TREE_TYPE (stmt);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "get vectype for scalar type: ");
- print_generic_expr (dump_file, scalar_type, TDF_SLIM);
- }
-
- vectype = get_vectype_for_scalar_type (scalar_type);
- if (!vectype)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: unsupported data-type ");
- print_generic_expr (dump_file, scalar_type, TDF_SLIM);
- }
- return false;
- }
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "vectype: ");
- print_generic_expr (dump_file, vectype, TDF_SLIM);
- }
- STMT_VINFO_VECTYPE (stmt_info) = vectype;
-
- ok = (vectorizable_operation (stmt, NULL, NULL)
- || vectorizable_assignment (stmt, NULL, NULL)
- || vectorizable_load (stmt, NULL, NULL)
- || vectorizable_store (stmt, NULL, NULL));
-
- if (!ok)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: stmt not supported: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- nunits = GET_MODE_NUNITS (TYPE_MODE (vectype));
- if (vect_debug_details (NULL))
- fprintf (dump_file, "nunits = %d", nunits);
-
- if (vectorization_factor)
- {
- /* FORNOW: don't allow mixed units.
- This restriction will be relaxed in the future. */
- if (nunits != vectorization_factor)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: mixed data-types");
- return false;
- }
- }
- else
- vectorization_factor = nunits;
-
-#ifdef ENABLE_CHECKING
- gcc_assert (GET_MODE_SIZE (TYPE_MODE (scalar_type))
- * vectorization_factor == UNITS_PER_SIMD_WORD);
-#endif
- }
- }
-
- /* TODO: Analyze cost. Decide if worth while to vectorize. */
-
- if (vectorization_factor <= 1)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unsupported data-type");
- return false;
- }
- LOOP_VINFO_VECT_FACTOR (loop_vinfo) = vectorization_factor;
-
-
- if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
- && vect_debug_details (NULL))
- fprintf (dump_file,
- "vectorization_factor = %d, niters = " HOST_WIDE_INT_PRINT_DEC,
- vectorization_factor, LOOP_VINFO_INT_NITERS (loop_vinfo));
-
- if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
- && LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0)
- {
- /* In this case we have to generate epilog loop, that
- can be done only for loops with one entry edge. */
- if (LOOP_VINFO_LOOP (loop_vinfo)->num_entries != 1
- || !(LOOP_VINFO_LOOP (loop_vinfo)->pre_header))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: more than one entry.");
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function exist_non_indexing_operands_for_use_p
-
- USE is one of the uses attached to STMT. Check if USE is
- used in STMT for anything other than indexing an array. */
-
-static bool
-exist_non_indexing_operands_for_use_p (tree use, tree stmt)
-{
- tree operand;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
-
- /* USE corresponds to some operand in STMT. If there is no data
- reference in STMT, then any operand that corresponds to USE
- is not indexing an array. */
- if (!STMT_VINFO_DATA_REF (stmt_info))
- return true;
-
- /* STMT has a data_ref. FORNOW this means that its of one of
- the following forms:
- -1- ARRAY_REF = var
- -2- var = ARRAY_REF
- (This should have been verified in analyze_data_refs).
-
- 'var' in the second case corresponds to a def, not a use,
- so USE cannot correspond to any operands that are not used
- for array indexing.
-
- Therefore, all we need to check is if STMT falls into the
- first case, and whether var corresponds to USE. */
-
- if (TREE_CODE (TREE_OPERAND (stmt, 0)) == SSA_NAME)
- return false;
-
- operand = TREE_OPERAND (stmt, 1);
-
- if (TREE_CODE (operand) != SSA_NAME)
- return false;
-
- if (operand == use)
- return true;
-
- return false;
-}
-
-
-/* Function vect_is_simple_iv_evolution.
-
- FORNOW: A simple evolution of an induction variables in the loop is
- considered a polynomial evolution with constant step. */
-
-static bool
-vect_is_simple_iv_evolution (unsigned loop_nb, tree access_fn, tree * init,
- tree * step, bool strict)
-{
- tree init_expr;
- tree step_expr;
-
- tree evolution_part = evolution_part_in_loop_num (access_fn, loop_nb);
-
- /* When there is no evolution in this loop, the evolution function
- is not "simple". */
- if (evolution_part == NULL_TREE)
- return false;
-
- /* When the evolution is a polynomial of degree >= 2
- the evolution function is not "simple". */
- if (tree_is_chrec (evolution_part))
- return false;
-
- step_expr = evolution_part;
- init_expr = unshare_expr (initial_condition (access_fn));
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "step: ");
- print_generic_expr (dump_file, step_expr, TDF_SLIM);
- fprintf (dump_file, ", init: ");
- print_generic_expr (dump_file, init_expr, TDF_SLIM);
- }
-
- *init = init_expr;
- *step = step_expr;
-
- if (TREE_CODE (step_expr) != INTEGER_CST)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "step unknown.");
- return false;
- }
-
- if (strict)
- if (!integer_onep (step_expr))
- {
- if (vect_debug_details (NULL))
- print_generic_expr (dump_file, step_expr, TDF_SLIM);
- return false;
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_scalar_cycles.
-
- Examine the cross iteration def-use cycles of scalar variables, by
- analyzing the loop (scalar) PHIs; verify that the cross iteration def-use
- cycles that they represent do not impede vectorization.
-
- FORNOW: Reduction as in the following loop, is not supported yet:
- loop1:
- for (i=0; i<N; i++)
- sum += a[i];
- The cross-iteration cycle corresponding to variable 'sum' will be
- considered too complicated and will impede vectorization.
-
- FORNOW: Induction as in the following loop, is not supported yet:
- loop2:
- for (i=0; i<N; i++)
- a[i] = i;
-
- However, the following loop *is* vectorizable:
- loop3:
- for (i=0; i<N; i++)
- a[i] = b[i];
-
- In both loops there exists a def-use cycle for the variable i:
- loop: i_2 = PHI (i_0, i_1)
- a[i_2] = ...;
- i_1 = i_2 + 1;
- GOTO loop;
-
- The evolution of the above cycle is considered simple enough,
- however, we also check that the cycle does not need to be
- vectorized, i.e - we check that the variable that this cycle
- defines is only used for array indexing or in stmts that do not
- need to be vectorized. This is not the case in loop2, but it
- *is* the case in loop3. */
-
-static bool
-vect_analyze_scalar_cycles (loop_vec_info loop_vinfo)
-{
- tree phi;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block bb = loop->header;
- tree dummy;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_scalar_cycles>>\n");
-
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- {
- tree access_fn = NULL;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Analyze phi: ");
- print_generic_expr (dump_file, phi, TDF_SLIM);
- }
-
- /* Skip virtual phi's. The data dependences that are associated with
- virtual defs/uses (i.e., memory accesses) are analyzed elsewhere. */
-
- if (!is_gimple_reg (SSA_NAME_VAR (PHI_RESULT (phi))))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "virtual phi. skip.");
- continue;
- }
-
- /* Analyze the evolution function. */
-
- /* FORNOW: The only scalar cross-iteration cycles that we allow are
- those of loop induction variables; This property is verified here.
-
- Furthermore, if that induction variable is used in an operation
- that needs to be vectorized (i.e, is not solely used to index
- arrays and check the exit condition) - we do not support its
- vectorization yet. This property is verified in vect_is_simple_use,
- during vect_analyze_operations. */
-
- access_fn = /* instantiate_parameters
- (loop,*/
- analyze_scalar_evolution (loop, PHI_RESULT (phi));
-
- if (!access_fn)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unsupported scalar cycle.");
- return false;
- }
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Access function of PHI: ");
- print_generic_expr (dump_file, access_fn, TDF_SLIM);
- }
-
- if (!vect_is_simple_iv_evolution (loop->num, access_fn, &dummy,
- &dummy, false))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unsupported scalar cycle.");
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_data_ref_dependence.
-
- Return TRUE if there (might) exist a dependence between a memory-reference
- DRA and a memory-reference DRB. */
-
-static bool
-vect_analyze_data_ref_dependence (struct data_reference *dra,
- struct data_reference *drb,
- struct loop *loop)
-{
- bool differ_p;
- struct data_dependence_relation *ddr;
-
- if (!array_base_name_differ_p (dra, drb, &differ_p))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file,
- "not vectorized: can't determine dependence between: ");
- print_generic_expr (dump_file, DR_REF (dra), TDF_SLIM);
- fprintf (dump_file, " and ");
- print_generic_expr (dump_file, DR_REF (drb), TDF_SLIM);
- }
- return true;
- }
-
- if (differ_p)
- return false;
-
- ddr = initialize_data_dependence_relation (dra, drb);
- compute_affine_dependence (ddr);
-
- if (DDR_ARE_DEPENDENT (ddr) == chrec_known)
- return false;
-
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file,
- "not vectorized: possible dependence between data-refs ");
- print_generic_expr (dump_file, DR_REF (dra), TDF_SLIM);
- fprintf (dump_file, " and ");
- print_generic_expr (dump_file, DR_REF (drb), TDF_SLIM);
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_data_ref_dependences.
-
- Examine all the data references in the loop, and make sure there do not
- exist any data dependences between them.
-
- TODO: dependences which distance is greater than the vectorization factor
- can be ignored. */
-
-static bool
-vect_analyze_data_ref_dependences (loop_vec_info loop_vinfo)
-{
- unsigned int i, j;
- varray_type loop_write_refs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- varray_type loop_read_refs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
-
- /* Examine store-store (output) dependences. */
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_dependences>>\n");
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "compare all store-store pairs.");
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_refs); i++)
- {
- for (j = i + 1; j < VARRAY_ACTIVE_SIZE (loop_write_refs); j++)
- {
- struct data_reference *dra =
- VARRAY_GENERIC_PTR (loop_write_refs, i);
- struct data_reference *drb =
- VARRAY_GENERIC_PTR (loop_write_refs, j);
- if (vect_analyze_data_ref_dependence (dra, drb, loop))
- return false;
- }
- }
-
- /* Examine load-store (true/anti) dependences. */
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "compare all load-store pairs.");
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_refs); i++)
- {
- for (j = 0; j < VARRAY_ACTIVE_SIZE (loop_write_refs); j++)
- {
- struct data_reference *dra = VARRAY_GENERIC_PTR (loop_read_refs, i);
- struct data_reference *drb =
- VARRAY_GENERIC_PTR (loop_write_refs, j);
- if (vect_analyze_data_ref_dependence (dra, drb, loop))
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function vect_get_first_index.
-
- REF is a data reference.
- If it is an ARRAY_REF: if its lower bound is simple enough,
- put it in ARRAY_FIRST_INDEX and return TRUE; otherwise - return FALSE.
- If it is not an ARRAY_REF: REF has no "first index";
- ARRAY_FIRST_INDEX in zero, and the function returns TRUE. */
-
-static bool
-vect_get_first_index (tree ref, tree *array_first_index)
-{
- tree array_start;
-
- if (TREE_CODE (ref) != ARRAY_REF)
- *array_first_index = size_zero_node;
- else
- {
- array_start = array_ref_low_bound (ref);
- if (!host_integerp (array_start,0))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "array min val not simple integer cst.");
- print_generic_expr (dump_file, array_start, TDF_DETAILS);
- }
- return false;
- }
- *array_first_index = array_start;
- }
-
- return true;
-}
-
-
-/* Function vect_compute_array_base_alignment.
- A utility function of vect_compute_array_ref_alignment.
-
- Compute the misalignment of ARRAY in bits.
-
- Input:
- ARRAY - an array_ref (possibly multidimensional) of type ARRAY_TYPE.
- VECTYPE - we are interested in the misalignment modulo the size of vectype.
- if NULL: don't compute misalignment, just return the base of ARRAY.
- PREV_DIMENSIONS - initialized to one.
- MISALIGNMENT - the computed misalignment in bits.
-
- Output:
- If VECTYPE is not NULL:
- Return NULL_TREE if the misalignment cannot be computed. Otherwise, return
- the base of the array, and put the computed misalignment in MISALIGNMENT.
- If VECTYPE is NULL:
- Return the base of the array.
-
- For a[idx_N]...[idx_2][idx_1][idx_0], the address of
- a[idx_N]...[idx_2][idx_1] is
- {&a + idx_1 * dim_0 + idx_2 * dim_0 * dim_1 + ...
- ... + idx_N * dim_0 * ... * dim_N-1}.
- (The misalignment of &a is not checked here).
- Note, that every term contains dim_0, therefore, if dim_0 is a
- multiple of NUNITS, the whole sum is a multiple of NUNITS.
- Otherwise, if idx_1 is constant, and dim_1 is a multiple of
- NUINTS, we can say that the misalignment of the sum is equal to
- the misalignment of {idx_1 * dim_0}. If idx_1 is not constant,
- we can't determine this array misalignment, and we return
- false.
- We proceed recursively in this manner, accumulating total misalignment
- and the multiplication of previous dimensions for correct misalignment
- calculation. */
-
-static tree
-vect_compute_array_base_alignment (tree array,
- tree vectype,
- tree *prev_dimensions,
- tree *misalignment)
-{
- tree index;
- tree domain;
- tree dimension_size;
- tree mis;
- tree bits_per_vectype;
- tree bits_per_vectype_unit;
-
- /* The 'stop condition' of the recursion. */
- if (TREE_CODE (array) != ARRAY_REF)
- return array;
-
- if (!vectype)
- /* Just get the base decl. */
- return vect_compute_array_base_alignment
- (TREE_OPERAND (array, 0), NULL, NULL, NULL);
-
- if (!host_integerp (*misalignment, 1) || TREE_OVERFLOW (*misalignment) ||
- !host_integerp (*prev_dimensions, 1) || TREE_OVERFLOW (*prev_dimensions))
- return NULL_TREE;
-
- domain = TYPE_DOMAIN (TREE_TYPE (array));
- dimension_size =
- int_const_binop (PLUS_EXPR,
- int_const_binop (MINUS_EXPR, TYPE_MAX_VALUE (domain),
- TYPE_MIN_VALUE (domain), 1),
- size_one_node, 1);
-
- /* Check if the dimension size is a multiple of NUNITS, the remaining sum
- is a multiple of NUNITS:
-
- dimension_size % GET_MODE_NUNITS (TYPE_MODE (vectype)) == 0 ?
- */
- mis = int_const_binop (TRUNC_MOD_EXPR, dimension_size,
- build_int_cst (NULL_TREE, GET_MODE_NUNITS (TYPE_MODE (vectype))), 1);
- if (integer_zerop (mis))
- /* This array is aligned. Continue just in order to get the base decl. */
- return vect_compute_array_base_alignment
- (TREE_OPERAND (array, 0), NULL, NULL, NULL);
-
- index = TREE_OPERAND (array, 1);
- if (!host_integerp (index, 1))
- /* The current index is not constant. */
- return NULL_TREE;
-
- index = int_const_binop (MINUS_EXPR, index, TYPE_MIN_VALUE (domain), 0);
-
- bits_per_vectype = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, BITS_PER_UNIT *
- GET_MODE_SIZE (TYPE_MODE (vectype))));
- bits_per_vectype_unit = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, BITS_PER_UNIT *
- GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (vectype)))));
-
- /* Add {idx_i * dim_i-1 * ... * dim_0 } to the misalignment computed
- earlier:
-
- *misalignment =
- (*misalignment + index_val * dimension_size * *prev_dimensions)
- % vectype_nunits;
- */
-
- mis = int_const_binop (MULT_EXPR, index, dimension_size, 1);
- mis = int_const_binop (MULT_EXPR, mis, *prev_dimensions, 1);
- mis = int_const_binop (MULT_EXPR, mis, bits_per_vectype_unit, 1);
- mis = int_const_binop (PLUS_EXPR, *misalignment, mis, 1);
- *misalignment = int_const_binop (TRUNC_MOD_EXPR, mis, bits_per_vectype, 1);
-
-
- *prev_dimensions = int_const_binop (MULT_EXPR,
- *prev_dimensions, dimension_size, 1);
-
- return vect_compute_array_base_alignment (TREE_OPERAND (array, 0), vectype,
- prev_dimensions,
- misalignment);
-}
-
-
-/* Function vect_compute_data_ref_alignment
-
- Compute the misalignment of the data reference DR.
-
- Output:
- 1. If during the misalignment computation it is found that the data reference
- cannot be vectorized then false is returned.
- 2. DR_MISALIGNMENT (DR) is defined.
-
- FOR NOW: No analysis is actually performed. Misalignment is calculated
- only for trivial cases. TODO. */
-
-static bool
-vect_compute_data_ref_alignment (struct data_reference *dr,
- loop_vec_info loop_vinfo)
-{
- tree stmt = DR_STMT (dr);
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree ref = DR_REF (dr);
- tree vectype;
- tree scalar_type;
- tree offset = size_zero_node;
- tree base, bit_offset, alignment;
- tree unit_bits = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, BITS_PER_UNIT));
- tree dr_base;
- bool base_aligned_p;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "vect_compute_data_ref_alignment:");
-
- /* Initialize misalignment to unknown. */
- DR_MISALIGNMENT (dr) = -1;
-
- scalar_type = TREE_TYPE (ref);
- vectype = get_vectype_for_scalar_type (scalar_type);
- if (!vectype)
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "no vectype for stmt: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- fprintf (dump_file, " scalar_type: ");
- print_generic_expr (dump_file, scalar_type, TDF_DETAILS);
- }
- /* It is not possible to vectorize this data reference. */
- return false;
- }
- STMT_VINFO_VECTYPE (stmt_info) = vectype;
- gcc_assert (TREE_CODE (ref) == ARRAY_REF || TREE_CODE (ref) == INDIRECT_REF);
-
- if (TREE_CODE (ref) == ARRAY_REF)
- dr_base = ref;
- else
- dr_base = STMT_VINFO_VECT_DR_BASE (stmt_info);
-
- base = vect_get_base_and_bit_offset (dr, dr_base, vectype,
- loop_vinfo, &bit_offset, &base_aligned_p);
- if (!base)
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Unknown alignment for access: ");
- print_generic_expr (dump_file,
- STMT_VINFO_VECT_DR_BASE (stmt_info), TDF_SLIM);
- }
- return true;
- }
-
- if (!base_aligned_p)
- {
- if (!vect_can_force_dr_alignment_p (base, TYPE_ALIGN (vectype)))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "can't force alignment of ref: ");
- print_generic_expr (dump_file, ref, TDF_SLIM);
- }
- return true;
- }
-
- /* Force the alignment of the decl.
- NOTE: This is the only change to the code we make during
- the analysis phase, before deciding to vectorize the loop. */
- if (vect_debug_details (NULL))
- fprintf (dump_file, "force alignment");
- DECL_ALIGN (base) = TYPE_ALIGN (vectype);
- DECL_USER_ALIGN (base) = TYPE_ALIGN (vectype);
- }
-
- /* At this point we assume that the base is aligned, and the offset from it
- (including index, if relevant) has been computed and is in BIT_OFFSET. */
- gcc_assert (base_aligned_p
- || (TREE_CODE (base) == VAR_DECL
- && DECL_ALIGN (base) >= TYPE_ALIGN (vectype)));
-
- /* Convert into bytes. */
- offset = int_const_binop (TRUNC_DIV_EXPR, bit_offset, unit_bits, 1);
- /* Check that there is no remainder in bits. */
- bit_offset = int_const_binop (TRUNC_MOD_EXPR, bit_offset, unit_bits, 1);
- if (!integer_zerop (bit_offset))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "bit offset alignment: ");
- print_generic_expr (dump_file, bit_offset, TDF_SLIM);
- }
- return false;
- }
-
- /* Alignment required, in bytes: */
- alignment = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, TYPE_ALIGN (vectype)/BITS_PER_UNIT));
-
- /* Modulo alignment. */
- offset = int_const_binop (TRUNC_MOD_EXPR, offset, alignment, 0);
- if (!host_integerp (offset, 1) || TREE_OVERFLOW (offset))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "unexpected misalign value");
- return false;
- }
-
- DR_MISALIGNMENT (dr) = tree_low_cst (offset, 1);
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "misalign = %d", DR_MISALIGNMENT (dr));
-
- return true;
-}
-
-
-/* Function vect_compute_array_ref_alignment
-
- Compute the alignment of an array-ref.
- The alignment we compute here is relative to
- TYPE_ALIGN(VECTYPE) boundary.
-
- Output:
- OFFSET - the alignment in bits
- Return value - the base of the array-ref. E.g,
- if the array-ref is a.b[k].c[i][j] the returned
- base is a.b[k].c
-*/
-
-static tree
-vect_compute_array_ref_alignment (struct data_reference *dr,
- loop_vec_info loop_vinfo,
- tree vectype,
- tree *offset)
-{
- tree array_first_index = size_zero_node;
- tree init;
- tree ref = DR_REF (dr);
- tree scalar_type = TREE_TYPE (ref);
- tree oprnd0 = TREE_OPERAND (ref, 0);
- tree dims = size_one_node;
- tree misalign = size_zero_node;
- tree next_ref, this_offset = size_zero_node;
- tree nunits;
- tree nbits;
-
- if (TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE)
- /* The reference is an array without its last index. */
- next_ref = vect_compute_array_base_alignment (ref, vectype, &dims,
- &misalign);
- else
- next_ref = vect_compute_array_base_alignment (oprnd0, vectype, &dims,
- &misalign);
- if (!vectype)
- /* Alignment is not requested. Just return the base. */
- return next_ref;
-
- /* Compute alignment. */
- if (!host_integerp (misalign, 1) || TREE_OVERFLOW (misalign) || !next_ref)
- return NULL_TREE;
- this_offset = misalign;
-
- /* Check the first index accessed. */
- if (!vect_get_first_index (ref, &array_first_index))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "no first_index for array.");
- return NULL_TREE;
- }
-
- /* Check the index of the array_ref. */
- init = initial_condition_in_loop_num (DR_ACCESS_FN (dr, 0),
- LOOP_VINFO_LOOP (loop_vinfo)->num);
-
- /* FORNOW: In order to simplify the handling of alignment, we make sure
- that the first location at which the array is accessed ('init') is on an
- 'NUNITS' boundary, since we are assuming here that 'array base' is aligned.
- This is too conservative, since we require that
- both {'array_base' is a multiple of NUNITS} && {'init' is a multiple of
- NUNITS}, instead of just {('array_base' + 'init') is a multiple of NUNITS}.
- This should be relaxed in the future. */
-
- if (!init || !host_integerp (init, 0))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "non constant init. ");
- return NULL_TREE;
- }
-
- /* bytes per scalar element: */
- nunits = fold_convert (unsigned_type_node,
- build_int_cst (NULL_TREE, GET_MODE_SIZE (TYPE_MODE (scalar_type))));
- nbits = int_const_binop (MULT_EXPR, nunits,
- build_int_cst (NULL_TREE, BITS_PER_UNIT), 1);
-
- /* misalign = offset + (init-array_first_index)*nunits*bits_in_byte */
- misalign = int_const_binop (MINUS_EXPR, init, array_first_index, 0);
- misalign = int_const_binop (MULT_EXPR, misalign, nbits, 0);
- misalign = int_const_binop (PLUS_EXPR, misalign, this_offset, 0);
-
- /* TODO: allow negative misalign values. */
- if (!host_integerp (misalign, 1) || TREE_OVERFLOW (misalign))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "unexpected misalign value");
- return NULL_TREE;
- }
- *offset = misalign;
- return next_ref;
-}
-
-
-/* Function vect_compute_data_refs_alignment
-
- Compute the misalignment of data references in the loop.
- This pass may take place at function granularity instead of at loop
- granularity.
-
- FOR NOW: No analysis is actually performed. Misalignment is calculated
- only for trivial cases. TODO. */
-
-static bool
-vect_compute_data_refs_alignment (loop_vec_info loop_vinfo)
-{
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- unsigned int i;
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- if (!vect_compute_data_ref_alignment (dr, loop_vinfo))
- return false;
- }
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- if (!vect_compute_data_ref_alignment (dr, loop_vinfo))
- return false;
- }
-
- return true;
-}
-
-
-/* Function vect_enhance_data_refs_alignment
-
- This pass will use loop versioning and loop peeling in order to enhance
- the alignment of data references in the loop.
-
- FOR NOW: we assume that whatever versioning/peeling takes place, only the
- original loop is to be vectorized; Any other loops that are created by
- the transformations performed in this pass - are not supposed to be
- vectorized. This restriction will be relaxed.
-
- FOR NOW: No transformation is actually performed. TODO. */
-
-static void
-vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
-{
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- unsigned int i;
-
- /*
- This pass will require a cost model to guide it whether to apply peeling
- or versioning or a combination of the two. For example, the scheme that
- intel uses when given a loop with several memory accesses, is as follows:
- choose one memory access ('p') which alignment you want to force by doing
- peeling. Then, either (1) generate a loop in which 'p' is aligned and all
- other accesses are not necessarily aligned, or (2) use loop versioning to
- generate one loop in which all accesses are aligned, and another loop in
- which only 'p' is necessarily aligned.
-
- ("Automatic Intra-Register Vectorization for the Intel Architecture",
- Aart J.C. Bik, Milind Girkar, Paul M. Grey and Ximmin Tian, International
- Journal of Parallel Programming, Vol. 30, No. 2, April 2002.)
-
- Devising a cost model is the most critical aspect of this work. It will
- guide us on which access to peel for, whether to use loop versioning, how
- many versions to create, etc. The cost model will probably consist of
- generic considerations as well as target specific considerations (on
- powerpc for example, misaligned stores are more painful than misaligned
- loads).
-
- Here is the general steps involved in alignment enhancements:
-
- -- original loop, before alignment analysis:
- for (i=0; i<N; i++){
- x = q[i]; # DR_MISALIGNMENT(q) = unknown
- p[i] = y; # DR_MISALIGNMENT(p) = unknown
- }
-
- -- After vect_compute_data_refs_alignment:
- for (i=0; i<N; i++){
- x = q[i]; # DR_MISALIGNMENT(q) = 3
- p[i] = y; # DR_MISALIGNMENT(p) = unknown
- }
-
- -- Possibility 1: we do loop versioning:
- if (p is aligned) {
- for (i=0; i<N; i++){ # loop 1A
- x = q[i]; # DR_MISALIGNMENT(q) = 3
- p[i] = y; # DR_MISALIGNMENT(p) = 0
- }
- }
- else {
- for (i=0; i<N; i++){ # loop 1B
- x = q[i]; # DR_MISALIGNMENT(q) = 3
- p[i] = y; # DR_MISALIGNMENT(p) = unaligned
- }
- }
-
- -- Possibility 2: we do loop peeling:
- for (i = 0; i < 3; i++){ # (scalar loop, not to be vectorized).
- x = q[i];
- p[i] = y;
- }
- for (i = 3; i < N; i++){ # loop 2A
- x = q[i]; # DR_MISALIGNMENT(q) = 0
- p[i] = y; # DR_MISALIGNMENT(p) = unknown
- }
-
- -- Possibility 3: combination of loop peeling and versioning:
- for (i = 0; i < 3; i++){ # (scalar loop, not to be vectorized).
- x = q[i];
- p[i] = y;
- }
- if (p is aligned) {
- for (i = 3; i<N; i++){ # loop 3A
- x = q[i]; # DR_MISALIGNMENT(q) = 0
- p[i] = y; # DR_MISALIGNMENT(p) = 0
- }
- }
- else {
- for (i = 3; i<N; i++){ # loop 3B
- x = q[i]; # DR_MISALIGNMENT(q) = 0
- p[i] = y; # DR_MISALIGNMENT(p) = unaligned
- }
- }
-
- These loops are later passed to loop_transform to be vectorized. The
- vectorizer will use the alignment information to guide the transformation
- (whether to generate regular loads/stores, or with special handling for
- misalignment).
- */
-
- /* (1) Peeling to force alignment. */
-
- /* (1.1) Decide whether to perform peeling, and how many iterations to peel:
- Considerations:
- + How many accesses will become aligned due to the peeling
- - How many accesses will become unaligned due to the peeling,
- and the cost of misaligned accesses.
- - The cost of peeling (the extra runtime checks, the increase
- in code size).
-
- The scheme we use FORNOW: peel to force the alignment of the first
- misaligned store in the loop.
- Rationale: misaligned stores are not yet supported.
-
- TODO: Use a better cost model. */
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- if (!aligned_access_p (dr))
- {
- LOOP_VINFO_UNALIGNED_DR (loop_vinfo) = dr;
- LOOP_DO_PEELING_FOR_ALIGNMENT (loop_vinfo) = true;
- break;
- }
- }
-
- if (!LOOP_VINFO_UNALIGNED_DR (loop_vinfo))
- {
- if (vect_debug_details (loop))
- fprintf (dump_file, "Peeling for alignment will not be applied.");
- return;
- }
- else
- if (vect_debug_details (loop))
- fprintf (dump_file, "Peeling for alignment will be applied.");
-
-
- /* (1.2) Update the alignment info according to the peeling factor.
- If the misalignment of the DR we peel for is M, then the
- peeling factor is VF - M, and the misalignment of each access DR_i
- in the loop is DR_MISALIGNMENT (DR_i) + VF - M.
- If the misalignment of the DR we peel for is unknown, then the
- misalignment of each access DR_i in the loop is also unknown.
-
- FORNOW: set the misalignment of the accesses to unknown even
- if the peeling factor is known at compile time.
-
- TODO: - if the peeling factor is known at compile time, use that
- when updating the misalignment info of the loop DRs.
- - consider accesses that are known to have the same
- alignment, even if that alignment is unknown. */
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- if (dr == LOOP_VINFO_UNALIGNED_DR (loop_vinfo))
- DR_MISALIGNMENT (dr) = 0;
- else
- DR_MISALIGNMENT (dr) = -1;
- }
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- if (dr == LOOP_VINFO_UNALIGNED_DR (loop_vinfo))
- DR_MISALIGNMENT (dr) = 0;
- else
- DR_MISALIGNMENT (dr) = -1;
- }
-}
-
-
-/* Function vect_analyze_data_refs_alignment
-
- Analyze the alignment of the data-references in the loop.
- FOR NOW: Until support for misliagned accesses is in place, only if all
- accesses are aligned can the loop be vectorized. This restriction will be
- relaxed. */
-
-static bool
-vect_analyze_data_refs_alignment (loop_vec_info loop_vinfo)
-{
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- enum dr_alignment_support supportable_dr_alignment;
- unsigned int i;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_data_refs_alignment>>\n");
-
-
- /* This pass may take place at function granularity instead of at loop
- granularity. */
-
- if (!vect_compute_data_refs_alignment (loop_vinfo))
- {
- if (vect_debug_details (loop) || vect_debug_stats (loop))
- fprintf (dump_file,
- "not vectorized: can't calculate alignment for data ref.");
- return false;
- }
-
-
- /* This pass will decide on using loop versioning and/or loop peeling in
- order to enhance the alignment of data references in the loop. */
-
- vect_enhance_data_refs_alignment (loop_vinfo);
-
-
- /* Finally, check that all the data references in the loop can be
- handled with respect to their alignment. */
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- supportable_dr_alignment = vect_supportable_dr_alignment (dr);
- if (!supportable_dr_alignment)
- {
- if (vect_debug_details (loop) || vect_debug_stats (loop))
- fprintf (dump_file, "not vectorized: unsupported unaligned load.");
- return false;
- }
- }
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- supportable_dr_alignment = vect_supportable_dr_alignment (dr);
- if (!supportable_dr_alignment)
- {
- if (vect_debug_details (loop) || vect_debug_stats (loop))
- fprintf (dump_file, "not vectorized: unsupported unaligned store.");
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_data_ref_access.
-
- Analyze the access pattern of the data-reference DR. For now, a data access
- has to consecutive and aligned to be considered vectorizable. */
-
-static bool
-vect_analyze_data_ref_access (struct data_reference *dr)
-{
- varray_type access_fns = DR_ACCESS_FNS (dr);
- tree access_fn;
- tree init, step;
- unsigned int dimensions, i;
-
- /* Check that in case of multidimensional array ref A[i1][i2]..[iN],
- i1, i2, ..., iN-1 are loop invariant (to make sure that the memory
- access is contiguous). */
- dimensions = VARRAY_ACTIVE_SIZE (access_fns);
-
- for (i = 1; i < dimensions; i++) /* Not including the last dimension. */
- {
- access_fn = DR_ACCESS_FN (dr, i);
-
- if (evolution_part_in_loop_num (access_fn,
- loop_containing_stmt (DR_STMT (dr))->num))
- {
- /* Evolution part is not NULL in this loop (it is neither constant
- nor invariant). */
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file,
- "not vectorized: complicated multidim. array access.");
- print_generic_expr (dump_file, access_fn, TDF_SLIM);
- }
- return false;
- }
- }
-
- access_fn = DR_ACCESS_FN (dr, 0); /* The last dimension access function. */
- if (!evolution_function_is_constant_p (access_fn)
- && !vect_is_simple_iv_evolution (loop_containing_stmt (DR_STMT (dr))->num,
- access_fn, &init, &step, true))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "not vectorized: complicated access function.");
- print_generic_expr (dump_file, access_fn, TDF_SLIM);
- }
- return false;
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_data_ref_accesses.
-
- Analyze the access pattern of all the data references in the loop.
-
- FORNOW: the only access pattern that is considered vectorizable is a
- simple step 1 (consecutive) access.
-
- FORNOW: handle only arrays and pointer accesses. */
-
-static bool
-vect_analyze_data_ref_accesses (loop_vec_info loop_vinfo)
-{
- unsigned int i;
- varray_type loop_write_datarefs = LOOP_VINFO_DATAREF_WRITES (loop_vinfo);
- varray_type loop_read_datarefs = LOOP_VINFO_DATAREF_READS (loop_vinfo);
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_data_ref_accesses>>\n");
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_write_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_write_datarefs, i);
- bool ok = vect_analyze_data_ref_access (dr);
- if (!ok)
- {
- if (vect_debug_stats (LOOP_VINFO_LOOP (loop_vinfo))
- || vect_debug_details (LOOP_VINFO_LOOP (loop_vinfo)))
- fprintf (dump_file, "not vectorized: complicated access pattern.");
- return false;
- }
- }
-
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_read_datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (loop_read_datarefs, i);
- bool ok = vect_analyze_data_ref_access (dr);
- if (!ok)
- {
- if (vect_debug_stats (LOOP_VINFO_LOOP (loop_vinfo))
- || vect_debug_details (LOOP_VINFO_LOOP (loop_vinfo)))
- fprintf (dump_file, "not vectorized: complicated access pattern.");
- return false;
- }
- }
-
- return true;
-}
-
-
-/* Function vect_analyze_pointer_ref_access.
-
- Input:
- STMT - a stmt that contains a data-ref
- MEMREF - a data-ref in STMT, which is an INDIRECT_REF.
-
- If the data-ref access is vectorizable, return a data_reference structure
- that represents it (DR). Otherwise - return NULL. */
-
-static struct data_reference *
-vect_analyze_pointer_ref_access (tree memref, tree stmt, bool is_read)
-{
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- struct loop *loop = STMT_VINFO_LOOP (stmt_info);
- tree access_fn = analyze_scalar_evolution (loop, TREE_OPERAND (memref, 0));
- tree init, step;
- int step_val;
- tree reftype, innertype;
- enum machine_mode innermode;
- tree indx_access_fn;
- int loopnum = loop->num;
- struct data_reference *dr;
-
- if (!access_fn)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: complicated pointer access.");
- return NULL;
- }
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Access function of ptr: ");
- print_generic_expr (dump_file, access_fn, TDF_SLIM);
- }
-
- if (!vect_is_simple_iv_evolution (loopnum, access_fn, &init, &step, false))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: pointer access is not simple.");
- return NULL;
- }
-
- STRIP_NOPS (init);
-
- if (!host_integerp (step,0))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "not vectorized: non constant step for pointer access.");
- return NULL;
- }
-
- step_val = TREE_INT_CST_LOW (step);
-
- reftype = TREE_TYPE (TREE_OPERAND (memref, 0));
- if (TREE_CODE (reftype) != POINTER_TYPE)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unexpected pointer access form.");
- return NULL;
- }
-
- reftype = TREE_TYPE (init);
- if (TREE_CODE (reftype) != POINTER_TYPE)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unexpected pointer access form.");
- return NULL;
- }
-
- innertype = TREE_TYPE (reftype);
- innermode = TYPE_MODE (innertype);
- if (GET_MODE_SIZE (innermode) != step_val)
- {
- /* FORNOW: support only consecutive access */
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: non consecutive access.");
- return NULL;
- }
-
- indx_access_fn =
- build_polynomial_chrec (loopnum, integer_zero_node, integer_one_node);
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Access function of ptr indx: ");
- print_generic_expr (dump_file, indx_access_fn, TDF_SLIM);
- }
- dr = init_data_ref (stmt, memref, init, indx_access_fn, is_read);
- return dr;
-}
-
-
-/* Function vect_get_symbl_and_dr.
-
- The function returns SYMBL - the relevant variable for
- memory tag (for aliasing purposes).
- Also data reference structure DR is created.
-
- Input:
- MEMREF - data reference in STMT
- IS_READ - TRUE if STMT reads from MEMREF, FALSE if writes to MEMREF
-
- Output:
- DR - data_reference struct for MEMREF
- return value - the relevant variable for memory tag (for aliasing purposes).
-
-*/
-
-static tree
-vect_get_symbl_and_dr (tree memref, tree stmt, bool is_read,
- loop_vec_info loop_vinfo, struct data_reference **dr)
-{
- tree symbl, oprnd0, oprnd1;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree offset;
- tree array_base, base;
- struct data_reference *new_dr;
- bool base_aligned_p;
-
- *dr = NULL;
- switch (TREE_CODE (memref))
- {
- case INDIRECT_REF:
- new_dr = vect_analyze_pointer_ref_access (memref, stmt, is_read);
- if (! new_dr)
- return NULL_TREE;
- *dr = new_dr;
- symbl = DR_BASE_NAME (new_dr);
- STMT_VINFO_VECT_DR_BASE (stmt_info) = symbl;
-
- switch (TREE_CODE (symbl))
- {
- case PLUS_EXPR:
- case MINUS_EXPR:
- oprnd0 = TREE_OPERAND (symbl, 0);
- oprnd1 = TREE_OPERAND (symbl, 1);
-
- STRIP_NOPS(oprnd1);
- /* Only {address_base + offset} expressions are supported,
- where address_base can be POINTER_TYPE or ARRAY_TYPE and
- offset can be anything but POINTER_TYPE or ARRAY_TYPE.
- TODO: swap operands if {offset + address_base}. */
- if ((TREE_CODE (TREE_TYPE (oprnd1)) == POINTER_TYPE
- && TREE_CODE (oprnd1) != INTEGER_CST)
- || TREE_CODE (TREE_TYPE (oprnd1)) == ARRAY_TYPE)
- return NULL_TREE;
-
- if (TREE_CODE (TREE_TYPE (oprnd0)) == POINTER_TYPE)
- symbl = oprnd0;
- else
- symbl = vect_get_symbl_and_dr (oprnd0, stmt, is_read,
- loop_vinfo, &new_dr);
-
- case SSA_NAME:
- case ADDR_EXPR:
- /* symbl remains unchanged. */
- break;
-
- default:
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unhandled data ref: ");
- print_generic_expr (dump_file, memref, TDF_SLIM);
- fprintf (dump_file, " (symbl ");
- print_generic_expr (dump_file, symbl, TDF_SLIM);
- fprintf (dump_file, ") in stmt ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return NULL_TREE;
- }
- break;
-
- case ARRAY_REF:
- offset = size_zero_node;
-
- /* Store the array base in the stmt info.
- For one dimensional array ref a[i], the base is a,
- for multidimensional a[i1][i2]..[iN], the base is
- a[i1][i2]..[iN-1]. */
- array_base = TREE_OPERAND (memref, 0);
- STMT_VINFO_VECT_DR_BASE (stmt_info) = array_base;
-
- new_dr = analyze_array (stmt, memref, is_read);
- *dr = new_dr;
-
- /* Find the relevant symbol for aliasing purposes. */
- base = DR_BASE_NAME (new_dr);
- switch (TREE_CODE (base))
- {
- case VAR_DECL:
- symbl = base;
- break;
-
- case INDIRECT_REF:
- symbl = TREE_OPERAND (base, 0);
- break;
-
- case COMPONENT_REF:
- /* Could have recorded more accurate information -
- i.e, the actual FIELD_DECL that is being referenced -
- but later passes expect VAR_DECL as the nmt. */
- symbl = vect_get_base_and_bit_offset (new_dr, base, NULL_TREE,
- loop_vinfo, &offset, &base_aligned_p);
- if (symbl)
- break;
- /* fall through */
- default:
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unhandled struct/class field access ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return NULL_TREE;
- }
- break;
-
- default:
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unhandled data ref: ");
- print_generic_expr (dump_file, memref, TDF_SLIM);
- fprintf (dump_file, " in stmt ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return NULL_TREE;
- }
- return symbl;
-}
-
-
-/* Function vect_analyze_data_refs.
-
- Find all the data references in the loop.
-
- FORNOW: Handle aligned INDIRECT_REFs and ARRAY_REFs
- which base is really an array (not a pointer) and which alignment
- can be forced. This restriction will be relaxed. */
-
-static bool
-vect_analyze_data_refs (loop_vec_info loop_vinfo)
-{
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
- int nbbs = loop->num_nodes;
- block_stmt_iterator si;
- int j;
- struct data_reference *dr;
- tree tag;
- tree address_base;
- bool base_aligned_p;
- tree offset;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_analyze_data_refs>>\n");
-
- for (j = 0; j < nbbs; j++)
- {
- basic_block bb = bbs[j];
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- bool is_read = false;
- tree stmt = bsi_stmt (si);
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- v_may_def_optype v_may_defs = STMT_V_MAY_DEF_OPS (stmt);
- v_must_def_optype v_must_defs = STMT_V_MUST_DEF_OPS (stmt);
- vuse_optype vuses = STMT_VUSE_OPS (stmt);
- varray_type *datarefs = NULL;
- int nvuses, nv_may_defs, nv_must_defs;
- tree memref = NULL;
- tree symbl;
-
- /* Assumption: there exists a data-ref in stmt, if and only if
- it has vuses/vdefs. */
-
- if (!vuses && !v_may_defs && !v_must_defs)
- continue;
-
- nvuses = NUM_VUSES (vuses);
- nv_may_defs = NUM_V_MAY_DEFS (v_may_defs);
- nv_must_defs = NUM_V_MUST_DEFS (v_must_defs);
-
- if (nvuses && (nv_may_defs || nv_must_defs))
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unexpected vdefs and vuses in stmt: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "unexpected vops in stmt: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- if (vuses)
- {
- memref = TREE_OPERAND (stmt, 1);
- datarefs = &(LOOP_VINFO_DATAREF_READS (loop_vinfo));
- is_read = true;
- }
- else /* vdefs */
- {
- memref = TREE_OPERAND (stmt, 0);
- datarefs = &(LOOP_VINFO_DATAREF_WRITES (loop_vinfo));
- is_read = false;
- }
-
- /* Analyze MEMREF. If it is of a supported form, build data_reference
- struct for it (DR) and find the relevant symbol for aliasing
- purposes. */
- symbl = vect_get_symbl_and_dr (memref, stmt, is_read, loop_vinfo,
- &dr);
- if (!symbl)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: unhandled data ref: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
-
- /* Find and record the memtag assigned to this data-ref. */
- switch (TREE_CODE (symbl))
- {
- case VAR_DECL:
- STMT_VINFO_MEMTAG (stmt_info) = symbl;
- break;
-
- case SSA_NAME:
- symbl = SSA_NAME_VAR (symbl);
- tag = get_var_ann (symbl)->type_mem_tag;
- if (!tag)
- {
- tree ptr = TREE_OPERAND (memref, 0);
- if (TREE_CODE (ptr) == SSA_NAME)
- tag = get_var_ann (SSA_NAME_VAR (ptr))->type_mem_tag;
- }
- if (!tag)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: no memtag for ref.");
- return false;
- }
- STMT_VINFO_MEMTAG (stmt_info) = tag;
- break;
-
- case ADDR_EXPR:
- address_base = TREE_OPERAND (symbl, 0);
-
- switch (TREE_CODE (address_base))
- {
- case ARRAY_REF:
- dr = analyze_array (stmt, TREE_OPERAND (symbl, 0),
- DR_IS_READ(dr));
- STMT_VINFO_MEMTAG (stmt_info) =
- vect_get_base_and_bit_offset (dr, DR_BASE_NAME (dr), NULL_TREE,
- loop_vinfo, &offset,
- &base_aligned_p);
- break;
-
- case VAR_DECL:
- STMT_VINFO_MEMTAG (stmt_info) = address_base;
- break;
-
- default:
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file,
- "not vectorized: unhandled address expr: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return false;
- }
- break;
-
- default:
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: unsupported data-ref: ");
- print_generic_expr (dump_file, memref, TDF_SLIM);
- }
- return false;
- }
-
- VARRAY_PUSH_GENERIC_PTR (*datarefs, dr);
- STMT_VINFO_DATA_REF (stmt_info) = dr;
- }
- }
-
- return true;
-}
-
-
-/* Utility functions used by vect_mark_stmts_to_be_vectorized. */
-
-/* Function vect_mark_relevant.
-
- Mark STMT as "relevant for vectorization" and add it to WORKLIST. */
-
-static void
-vect_mark_relevant (varray_type worklist, tree stmt)
-{
- stmt_vec_info stmt_info;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "mark relevant.");
-
- if (TREE_CODE (stmt) == PHI_NODE)
- {
- VARRAY_PUSH_TREE (worklist, stmt);
- return;
- }
-
- stmt_info = vinfo_for_stmt (stmt);
-
- if (!stmt_info)
- {
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "mark relevant: no stmt info!!.");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
- return;
- }
-
- if (STMT_VINFO_RELEVANT_P (stmt_info))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "already marked relevant.");
- return;
- }
-
- STMT_VINFO_RELEVANT_P (stmt_info) = 1;
- VARRAY_PUSH_TREE (worklist, stmt);
-}
-
-
-/* Function vect_stmt_relevant_p.
-
- Return true if STMT in loop that is represented by LOOP_VINFO is
- "relevant for vectorization".
-
- A stmt is considered "relevant for vectorization" if:
- - it has uses outside the loop.
- - it has vdefs (it alters memory).
- - control stmts in the loop (except for the exit condition).
-
- CHECKME: what other side effects would the vectorizer allow? */
-
-static bool
-vect_stmt_relevant_p (tree stmt, loop_vec_info loop_vinfo)
-{
- v_may_def_optype v_may_defs;
- v_must_def_optype v_must_defs;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- int i;
- dataflow_t df;
- int num_uses;
-
- /* cond stmt other than loop exit cond. */
- if (is_ctrl_stmt (stmt) && (stmt != LOOP_VINFO_EXIT_COND (loop_vinfo)))
- return true;
-
- /* changing memory. */
- v_may_defs = STMT_V_MAY_DEF_OPS (stmt);
- v_must_defs = STMT_V_MUST_DEF_OPS (stmt);
- if (v_may_defs || v_must_defs)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "vec_stmt_relevant_p: stmt has vdefs.");
- return true;
- }
-
- /* uses outside the loop. */
- df = get_immediate_uses (stmt);
- num_uses = num_immediate_uses (df);
- for (i = 0; i < num_uses; i++)
- {
- tree use = immediate_use (df, i);
- basic_block bb = bb_for_stmt (use);
- if (!flow_bb_inside_loop_p (loop, bb))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "vec_stmt_relevant_p: used out of loop.");
- return true;
- }
- }
-
- return false;
-}
-
-
-/* Function vect_mark_stmts_to_be_vectorized.
-
- Not all stmts in the loop need to be vectorized. For example:
-
- for i...
- for j...
- 1. T0 = i + j
- 2. T1 = a[T0]
-
- 3. j = j + 1
-
- Stmt 1 and 3 do not need to be vectorized, because loop control and
- addressing of vectorized data-refs are handled differently.
-
- This pass detects such stmts. */
-
-static bool
-vect_mark_stmts_to_be_vectorized (loop_vec_info loop_vinfo)
-{
- varray_type worklist;
- struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo);
- unsigned int nbbs = loop->num_nodes;
- block_stmt_iterator si;
- tree stmt;
- stmt_ann_t ann;
- unsigned int i;
- int j;
- use_optype use_ops;
- stmt_vec_info stmt_info;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<vect_mark_stmts_to_be_vectorized>>\n");
-
- VARRAY_TREE_INIT (worklist, 64, "work list");
-
- /* 1. Init worklist. */
-
- for (i = 0; i < nbbs; i++)
- {
- basic_block bb = bbs[i];
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
- {
- stmt = bsi_stmt (si);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "init: stmt relevant? ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
-
- stmt_info = vinfo_for_stmt (stmt);
- STMT_VINFO_RELEVANT_P (stmt_info) = 0;
-
- if (vect_stmt_relevant_p (stmt, loop_vinfo))
- vect_mark_relevant (worklist, stmt);
- }
- }
-
-
- /* 2. Process_worklist */
-
- while (VARRAY_ACTIVE_SIZE (worklist) > 0)
- {
- stmt = VARRAY_TOP_TREE (worklist);
- VARRAY_POP (worklist);
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "worklist: examine stmt: ");
- print_generic_expr (dump_file, stmt, TDF_SLIM);
- }
+ return vectype;
+}
- /* Examine the USES in this statement. Mark all the statements which
- feed this statement's uses as "relevant", unless the USE is used as
- an array index. */
- if (TREE_CODE (stmt) == PHI_NODE)
- {
- /* follow the def-use chain inside the loop. */
- for (j = 0; j < PHI_NUM_ARGS (stmt); j++)
- {
- tree arg = PHI_ARG_DEF (stmt, j);
- tree def_stmt = NULL_TREE;
- basic_block bb;
- if (!vect_is_simple_use (arg, loop, &def_stmt))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "worklist: unsupported use.");
- varray_clear (worklist);
- return false;
- }
- if (!def_stmt)
- continue;
+/* Function vect_supportable_dr_alignment
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "worklist: def_stmt: ");
- print_generic_expr (dump_file, def_stmt, TDF_SLIM);
- }
+ Return whether the data reference DR is supported with respect to its
+ alignment. */
- bb = bb_for_stmt (def_stmt);
- if (flow_bb_inside_loop_p (loop, bb))
- vect_mark_relevant (worklist, def_stmt);
- }
- }
+enum dr_alignment_support
+vect_supportable_dr_alignment (struct data_reference *dr)
+{
+ tree vectype = STMT_VINFO_VECTYPE (vinfo_for_stmt (DR_STMT (dr)));
+ enum machine_mode mode = (int) TYPE_MODE (vectype);
- ann = stmt_ann (stmt);
- use_ops = USE_OPS (ann);
+ if (aligned_access_p (dr))
+ return dr_aligned;
- for (i = 0; i < NUM_USES (use_ops); i++)
- {
- tree use = USE_OP (use_ops, i);
+ /* Possibly unaligned access. */
+
+ if (DR_IS_READ (dr))
+ {
+ if (vec_realign_load_optab->handlers[mode].insn_code != CODE_FOR_nothing
+ && (!targetm.vectorize.builtin_mask_for_load
+ || targetm.vectorize.builtin_mask_for_load ()))
+ return dr_unaligned_software_pipeline;
- /* We are only interested in uses that need to be vectorized. Uses
- that are used for address computation are not considered relevant.
- */
- if (exist_non_indexing_operands_for_use_p (use, stmt))
- {
- tree def_stmt = NULL_TREE;
- basic_block bb;
- if (!vect_is_simple_use (use, loop, &def_stmt))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "worklist: unsupported use.");
- varray_clear (worklist);
- return false;
- }
-
- if (!def_stmt)
- continue;
-
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "worklist: examine use %d: ", i);
- print_generic_expr (dump_file, use, TDF_SLIM);
- }
-
- bb = bb_for_stmt (def_stmt);
- if (flow_bb_inside_loop_p (loop, bb))
- vect_mark_relevant (worklist, def_stmt);
- }
- }
- } /* while worklist */
+ if (movmisalign_optab->handlers[mode].insn_code != CODE_FOR_nothing)
+ /* Can't software pipeline the loads, but can at least do them. */
+ return dr_unaligned_supported;
+ }
- varray_clear (worklist);
- return true;
+ /* Unsupported. */
+ return dr_unaligned_unsupported;
}
-/* Function vect_analyze_loop_with_symbolic_num_of_iters.
+/* Function vect_is_simple_use.
- In case the number of iterations that LOOP iterates in unknown at compile
- time, an epilog loop will be generated, and the loop induction variables
- (IVs) will be "advanced" to the value they are supposed to take just before
- the epilog loop. Here we check that the access function of the loop IVs
- and the expression that represents the loop bound are simple enough.
- These restrictions will be relaxed in the future. */
+ Input:
+ LOOP - the loop that is being vectorized.
+ OPERAND - operand of a stmt in LOOP.
+ DEF - the defining stmt in case OPERAND is an SSA_NAME.
-static bool
-vect_analyze_loop_with_symbolic_num_of_iters (tree niters,
- struct loop *loop)
-{
- basic_block bb = loop->header;
- tree phi;
+ Returns whether a stmt with OPERAND can be vectorized.
+ Supportable operands are constants, loop invariants, and operands that are
+ defined by the current iteration of the loop. Unsupportable operands are
+ those that are defined by a previous iteration of the loop (as is the case
+ in reduction/induction computations). */
+
+bool
+vect_is_simple_use (tree operand, loop_vec_info loop_vinfo, tree *def_stmt,
+ tree *def, enum vect_def_type *dt)
+{
+ basic_block bb;
+ stmt_vec_info stmt_vinfo;
+ struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
- if (vect_debug_details (NULL))
- fprintf (dump_file,
- "\n<<vect_analyze_loop_with_symbolic_num_of_iters>>\n");
+ *def_stmt = NULL_TREE;
+ *def = NULL_TREE;
- if (chrec_contains_undetermined (niters))
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "vect_is_simple_use: operand ");
+ print_generic_expr (vect_dump, operand, TDF_SLIM);
+ }
+
+ if (TREE_CODE (operand) == INTEGER_CST || TREE_CODE (operand) == REAL_CST)
+ {
+ *dt = vect_constant_def;
+ return true;
+ }
+
+ if (TREE_CODE (operand) != SSA_NAME)
{
- if (vect_debug_details (NULL))
- fprintf (dump_file, "Infinite number of iterations.");
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "not ssa-name.");
return false;
}
-
- if (!niters)
+
+ *def_stmt = SSA_NAME_DEF_STMT (operand);
+ if (*def_stmt == NULL_TREE )
{
- if (vect_debug_details (NULL))
- fprintf (dump_file, "niters is NULL pointer.");
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "no def_stmt.");
return false;
}
- if (vect_debug_details (NULL))
+ if (vect_print_dump_info (REPORT_DETAILS))
{
- fprintf (dump_file, "Symbolic number of iterations is ");
- print_generic_expr (dump_file, niters, TDF_DETAILS);
+ fprintf (vect_dump, "def_stmt: ");
+ print_generic_expr (vect_dump, *def_stmt, TDF_SLIM);
}
-
- /* Analyze phi functions of the loop header. */
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+ /* empty stmt is expected only in case of a function argument.
+ (Otherwise - we expect a phi_node or a modify_expr). */
+ if (IS_EMPTY_STMT (*def_stmt))
{
- tree access_fn = NULL;
- tree evolution_part;
+ tree arg = TREE_OPERAND (*def_stmt, 0);
+ if (TREE_CODE (arg) == INTEGER_CST || TREE_CODE (arg) == REAL_CST)
+ {
+ *def = operand;
+ *dt = vect_invariant_def;
+ return true;
+ }
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Analyze phi: ");
- print_generic_expr (dump_file, phi, TDF_SLIM);
- }
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "Unexpected empty stmt.");
+ return false;
+ }
- /* Skip virtual phi's. The data dependences that are associated with
- virtual defs/uses (i.e., memory accesses) are analyzed elsewhere. */
+ bb = bb_for_stmt (*def_stmt);
+ if (!flow_bb_inside_loop_p (loop, bb))
+ *dt = vect_invariant_def;
+ else
+ {
+ stmt_vinfo = vinfo_for_stmt (*def_stmt);
+ *dt = STMT_VINFO_DEF_TYPE (stmt_vinfo);
+ }
- if (!is_gimple_reg (SSA_NAME_VAR (PHI_RESULT (phi))))
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "virtual phi. skip.");
- continue;
- }
+ if (*dt == vect_unknown_def_type)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "Unsupported pattern.");
+ return false;
+ }
- /* Analyze the evolution function. */
+ /* stmts inside the loop that have been identified as performing
+ a reduction operation cannot have uses in the loop. */
+ if (*dt == vect_reduction_def && TREE_CODE (*def_stmt) != PHI_NODE)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "reduction used in loop.");
+ return false;
+ }
- access_fn = instantiate_parameters
- (loop, analyze_scalar_evolution (loop, PHI_RESULT (phi)));
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "type of def: %d.",*dt);
- if (!access_fn)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "No Access function.");
- return false;
- }
+ switch (TREE_CODE (*def_stmt))
+ {
+ case PHI_NODE:
+ *def = PHI_RESULT (*def_stmt);
+ gcc_assert (*dt == vect_induction_def || *dt == vect_reduction_def
+ || *dt == vect_invariant_def);
+ break;
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "Access function of PHI: ");
- print_generic_expr (dump_file, access_fn, TDF_SLIM);
- }
+ case MODIFY_EXPR:
+ *def = TREE_OPERAND (*def_stmt, 0);
+ gcc_assert (*dt == vect_loop_def || *dt == vect_invariant_def);
+ break;
- evolution_part = evolution_part_in_loop_num (access_fn, loop->num);
-
- if (evolution_part == NULL_TREE)
- return false;
-
- /* FORNOW: We do not transform initial conditions of IVs
- which evolution functions are a polynomial of degree >= 2. */
+ default:
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "unsupported defining stmt: ");
+ return false;
+ }
- if (tree_is_chrec (evolution_part))
- return false;
+ if (*dt == vect_induction_def)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "induction not supported.");
+ return false;
}
- return true;
+ return true;
}
-/* Function vect_get_loop_niters.
+/* Function reduction_code_for_scalar_code
- Determine how many iterations the loop is executed. */
+ Input:
+ CODE - tree_code of a reduction operations.
-static tree
-vect_get_loop_niters (struct loop *loop, tree *number_of_iterations)
-{
- tree niters;
+ Output:
+ REDUC_CODE - the corresponding tree-code to be used to reduce the
+ vector of partial results into a single scalar result (which
+ will also reside in a vector).
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<get_loop_niters>>\n");
+ Return TRUE if a corresponding REDUC_CODE was found, FALSE otherwise. */
- niters = number_of_iterations_in_loop (loop);
+bool
+reduction_code_for_scalar_code (enum tree_code code,
+ enum tree_code *reduc_code)
+{
+ switch (code)
+ {
+ case MAX_EXPR:
+ *reduc_code = REDUC_MAX_EXPR;
+ return true;
- if (niters != NULL_TREE
- && niters != chrec_dont_know)
- {
- *number_of_iterations = niters;
+ case MIN_EXPR:
+ *reduc_code = REDUC_MIN_EXPR;
+ return true;
- if (vect_debug_details (NULL))
- {
- fprintf (dump_file, "==> get_loop_niters:" );
- print_generic_expr (dump_file, *number_of_iterations, TDF_SLIM);
- }
- }
+ case PLUS_EXPR:
+ *reduc_code = REDUC_PLUS_EXPR;
+ return true;
- return get_loop_exit_condition (loop);
+ default:
+ return false;
+ }
}
-/* Function vect_analyze_loop_form.
+/* Function vect_is_simple_reduction
- Verify the following restrictions (some may be relaxed in the future):
- - it's an inner-most loop
- - number of BBs = 2 (which are the loop header and the latch)
- - the loop has a pre-header
- - the loop has a single entry and exit
- - the loop exit condition is simple enough, and the number of iterations
- can be analyzed (a countable loop). */
+ Detect a cross-iteration def-use cucle that represents a simple
+ reduction computation. We look for the following pattern:
-static loop_vec_info
-vect_analyze_loop_form (struct loop *loop)
-{
- loop_vec_info loop_vinfo;
- tree loop_cond;
- tree number_of_iterations = NULL;
+ loop_header:
+ a1 = phi < a0, a2 >
+ a3 = ...
+ a2 = operation (a3, a1)
+
+ such that:
+ 1. operation is commutative and associative and it is safe to
+ change the order of the computation.
+ 2. no uses for a2 in the loop (a2 is used out of the loop)
+ 3. no uses of a1 in the loop besides the reduction operation.
- if (vect_debug_details (loop))
- fprintf (dump_file, "\n<<vect_analyze_loop_form>>\n");
+ Condition 1 is tested here.
+ Conditions 2,3 are tested in vect_mark_stmts_to_be_vectorized. */
- if (loop->inner
- || !loop->single_exit
- || loop->num_nodes != 2)
+tree
+vect_is_simple_reduction (struct loop *loop, tree phi)
+{
+ edge latch_e = loop_latch_edge (loop);
+ tree loop_arg = PHI_ARG_DEF_FROM_EDGE (phi, latch_e);
+ tree def_stmt, def1, def2;
+ enum tree_code code;
+ int op_type;
+ tree operation, op1, op2;
+ tree type;
+
+ if (TREE_CODE (loop_arg) != SSA_NAME)
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- {
- fprintf (dump_file, "not vectorized: bad loop form. ");
- if (loop->inner)
- fprintf (dump_file, "nested loop.");
- else if (!loop->single_exit)
- fprintf (dump_file, "multiple exits.");
- else if (loop->num_nodes != 2)
- fprintf (dump_file, "too many BBs in loop.");
- }
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "reduction: not ssa_name: ");
+ print_generic_expr (vect_dump, loop_arg, TDF_SLIM);
+ }
+ return NULL_TREE;
+ }
- return NULL;
+ def_stmt = SSA_NAME_DEF_STMT (loop_arg);
+ if (!def_stmt)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "reduction: no def_stmt.");
+ return NULL_TREE;
}
- /* We assume that the loop exit condition is at the end of the loop. i.e,
- that the loop is represented as a do-while (with a proper if-guard
- before the loop if needed), where the loop header contains all the
- executable statements, and the latch is empty. */
- if (!empty_block_p (loop->latch))
+ if (TREE_CODE (def_stmt) != MODIFY_EXPR)
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unexpectd loop form.");
- return NULL;
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ print_generic_expr (vect_dump, def_stmt, TDF_SLIM);
+ }
+ return NULL_TREE;
}
- if (empty_block_p (loop->header))
+ operation = TREE_OPERAND (def_stmt, 1);
+ code = TREE_CODE (operation);
+ if (!commutative_tree_code (code) || !associative_tree_code (code))
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: empty loop.");
- return NULL;
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "reduction: not commutative/associative: ");
+ print_generic_expr (vect_dump, operation, TDF_SLIM);
+ }
+ return NULL_TREE;
}
- loop_cond = vect_get_loop_niters (loop, &number_of_iterations);
- if (!loop_cond)
+ op_type = TREE_CODE_LENGTH (code);
+ if (op_type != binary_op)
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: complicated exit condition.");
- return NULL;
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "reduction: not binary operation: ");
+ print_generic_expr (vect_dump, operation, TDF_SLIM);
+ }
+ return NULL_TREE;
}
-
- if (!number_of_iterations)
+
+ op1 = TREE_OPERAND (operation, 0);
+ op2 = TREE_OPERAND (operation, 1);
+ if (TREE_CODE (op1) != SSA_NAME || TREE_CODE (op2) != SSA_NAME)
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "not vectorized: number of iterations cannot be computed.");
- return NULL;
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "reduction: uses not ssa_names: ");
+ print_generic_expr (vect_dump, operation, TDF_SLIM);
+ }
+ return NULL_TREE;
}
- loop_vinfo = new_loop_vec_info (loop);
- LOOP_VINFO_NITERS (loop_vinfo) = number_of_iterations;
- if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo))
+ /* Check that it's ok to change the order of the computation. */
+ type = TREE_TYPE (operation);
+ if (TYPE_MAIN_VARIANT (type) != TYPE_MAIN_VARIANT (TREE_TYPE (op1))
+ || TYPE_MAIN_VARIANT (type) != TYPE_MAIN_VARIANT (TREE_TYPE (op2)))
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "loop bound unknown.");
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "reduction: multiple types: operation type: ");
+ print_generic_expr (vect_dump, type, TDF_SLIM);
+ fprintf (vect_dump, ", operands types: ");
+ print_generic_expr (vect_dump, TREE_TYPE (op1), TDF_SLIM);
+ fprintf (vect_dump, ",");
+ print_generic_expr (vect_dump, TREE_TYPE (op2), TDF_SLIM);
+ }
+ return NULL_TREE;
+ }
- /* Unknown loop bound. */
- if (!vect_analyze_loop_with_symbolic_num_of_iters
- (number_of_iterations, loop))
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "not vectorized: can't determine loop bound.");
- return NULL;
- }
- else
- {
- /* We need only one loop entry for unknown loop bound support. */
- if (loop->num_entries != 1 || !loop->pre_header)
- {
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file,
- "not vectorized: more than one loop entry.");
- return NULL;
- }
- }
+ /* CHECKME: check for !flag_finite_math_only too? */
+ if (SCALAR_FLOAT_TYPE_P (type) && !flag_unsafe_math_optimizations)
+ {
+ /* Changing the order of operations changes the semantics. */
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "reduction: unsafe fp math optimization: ");
+ print_generic_expr (vect_dump, operation, TDF_SLIM);
+ }
+ return NULL_TREE;
}
- else
- if (LOOP_VINFO_INT_NITERS (loop_vinfo) == 0)
+ else if (INTEGRAL_TYPE_P (type) && !TYPE_UNSIGNED (type) && flag_trapv)
{
- if (vect_debug_stats (loop) || vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: number of iterations = 0.");
- return NULL;
+ /* Changing the order of operations changes the semantics. */
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "reduction: unsafe int math optimization: ");
+ print_generic_expr (vect_dump, operation, TDF_SLIM);
+ }
+ return NULL_TREE;
}
- LOOP_VINFO_EXIT_COND (loop_vinfo) = loop_cond;
-
- return loop_vinfo;
-}
-
-
-/* Function vect_analyze_loop.
-
- Apply a set of analyses on LOOP, and create a loop_vec_info struct
- for it. The different analyses will record information in the
- loop_vec_info struct. */
-
-static loop_vec_info
-vect_analyze_loop (struct loop *loop)
-{
- bool ok;
- loop_vec_info loop_vinfo;
-
- if (vect_debug_details (NULL))
- fprintf (dump_file, "\n<<<<<<< analyze_loop_nest >>>>>>>\n");
-
- /* Check the CFG characteristics of the loop (nesting, entry/exit, etc. */
-
- loop_vinfo = vect_analyze_loop_form (loop);
- if (!loop_vinfo)
+ /* reduction is safe. we're dealing with one of the following:
+ 1) integer arithmetic and no trapv
+ 2) floating point arithmetic, and special flags permit this optimization.
+ */
+ def1 = SSA_NAME_DEF_STMT (op1);
+ def2 = SSA_NAME_DEF_STMT (op2);
+ if (!def1 || !def2)
{
- if (vect_debug_details (loop))
- fprintf (dump_file, "bad loop form.");
- return NULL;
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "reduction: no defs for operands: ");
+ print_generic_expr (vect_dump, operation, TDF_SLIM);
+ }
+ return NULL_TREE;
}
- /* Find all data references in the loop (which correspond to vdefs/vuses)
- and analyze their evolution in the loop.
-
- FORNOW: Handle only simple, array references, which
- alignment can be forced, and aligned pointer-references. */
-
- ok = vect_analyze_data_refs (loop_vinfo);
- if (!ok)
+ if (TREE_CODE (def1) == MODIFY_EXPR
+ && flow_bb_inside_loop_p (loop, bb_for_stmt (def1))
+ && def2 == phi)
{
- if (vect_debug_details (loop))
- fprintf (dump_file, "bad data references.");
- destroy_loop_vec_info (loop_vinfo);
- return NULL;
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "detected reduction:");
+ print_generic_expr (vect_dump, operation, TDF_SLIM);
+ }
+ return def_stmt;
}
-
- /* Data-flow analysis to detect stmts that do not need to be vectorized. */
-
- ok = vect_mark_stmts_to_be_vectorized (loop_vinfo);
- if (!ok)
+ else if (TREE_CODE (def2) == MODIFY_EXPR
+ && flow_bb_inside_loop_p (loop, bb_for_stmt (def2))
+ && def1 == phi)
{
- if (vect_debug_details (loop))
- fprintf (dump_file, "unexpected pattern.");
- if (vect_debug_details (loop))
- fprintf (dump_file, "not vectorized: unexpected pattern.");
- destroy_loop_vec_info (loop_vinfo);
- return NULL;
+ /* Swap operands (just for simplicity - so that the rest of the code
+ can assume that the reduction variable is always the last (second)
+ argument). */
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "detected reduction: need to swap operands:");
+ print_generic_expr (vect_dump, operation, TDF_SLIM);
+ }
+ swap_tree_operands (def_stmt, &TREE_OPERAND (operation, 0),
+ &TREE_OPERAND (operation, 1));
+ return def_stmt;
}
-
- /* Check that all cross-iteration scalar data-flow cycles are OK.
- Cross-iteration cycles caused by virtual phis are analyzed separately. */
-
- ok = vect_analyze_scalar_cycles (loop_vinfo);
- if (!ok)
+ else
{
- if (vect_debug_details (loop))
- fprintf (dump_file, "bad scalar cycle.");
- destroy_loop_vec_info (loop_vinfo);
- return NULL;
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "reduction: unknown pattern.");
+ print_generic_expr (vect_dump, operation, TDF_SLIM);
+ }
+ return NULL_TREE;
}
+}
- /* Analyze data dependences between the data-refs in the loop.
- FORNOW: fail at the first data dependence that we encounter. */
- ok = vect_analyze_data_ref_dependences (loop_vinfo);
- if (!ok)
- {
- if (vect_debug_details (loop))
- fprintf (dump_file, "bad data dependence.");
- destroy_loop_vec_info (loop_vinfo);
- return NULL;
- }
+/* Function vect_is_simple_iv_evolution.
- /* Analyze the access patterns of the data-refs in the loop (consecutive,
- complex, etc.). FORNOW: Only handle consecutive access pattern. */
+ FORNOW: A simple evolution of an induction variables in the loop is
+ considered a polynomial evolution with constant step. */
- ok = vect_analyze_data_ref_accesses (loop_vinfo);
- if (!ok)
- {
- if (vect_debug_details (loop))
- fprintf (dump_file, "bad data access.");
- destroy_loop_vec_info (loop_vinfo);
- return NULL;
- }
+bool
+vect_is_simple_iv_evolution (unsigned loop_nb, tree access_fn, tree * init,
+ tree * step)
+{
+ tree init_expr;
+ tree step_expr;
+
+ tree evolution_part = evolution_part_in_loop_num (access_fn, loop_nb);
- /* Analyze the alignment of the data-refs in the loop.
- FORNOW: Only aligned accesses are handled. */
+ /* When there is no evolution in this loop, the evolution function
+ is not "simple". */
+ if (evolution_part == NULL_TREE)
+ return false;
+
+ /* When the evolution is a polynomial of degree >= 2
+ the evolution function is not "simple". */
+ if (tree_is_chrec (evolution_part))
+ return false;
+
+ step_expr = evolution_part;
+ init_expr = unshare_expr (initial_condition_in_loop_num (access_fn,
+ loop_nb));
- ok = vect_analyze_data_refs_alignment (loop_vinfo);
- if (!ok)
+ if (vect_print_dump_info (REPORT_DETAILS))
{
- if (vect_debug_details (loop))
- fprintf (dump_file, "bad data alignment.");
- destroy_loop_vec_info (loop_vinfo);
- return NULL;
+ fprintf (vect_dump, "step: ");
+ print_generic_expr (vect_dump, step_expr, TDF_SLIM);
+ fprintf (vect_dump, ", init: ");
+ print_generic_expr (vect_dump, init_expr, TDF_SLIM);
}
- /* Scan all the operations in the loop and make sure they are
- vectorizable. */
+ *init = init_expr;
+ *step = step_expr;
- ok = vect_analyze_operations (loop_vinfo);
- if (!ok)
+ if (TREE_CODE (step_expr) != INTEGER_CST)
{
- if (vect_debug_details (loop))
- fprintf (dump_file, "bad operation or unsupported loop bound.");
- destroy_loop_vec_info (loop_vinfo);
- return NULL;
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "step unknown.");
+ return false;
}
- LOOP_VINFO_VECTORIZABLE_P (loop_vinfo) = 1;
-
- return loop_vinfo;
-}
-
-
-/* Function need_imm_uses_for.
-
- Return whether we ought to include information for 'var'
- when calculating immediate uses. For this pass we only want use
- information for non-virtual variables. */
-
-static bool
-need_imm_uses_for (tree var)
-{
- return is_gimple_reg (var);
+ return true;
}
void
vectorize_loops (struct loops *loops)
{
- unsigned int i, loops_num;
+ unsigned int i;
unsigned int num_vectorized_loops = 0;
- /* Does the target support SIMD? */
- /* FORNOW: until more sophisticated machine modelling is in place. */
- if (!UNITS_PER_SIMD_WORD)
- {
- if (vect_debug_details (NULL))
- fprintf (dump_file, "vectorizer: target vector size is not defined.");
- return;
- }
+ /* Fix the verbosity level if not defined explicitly by the user. */
+ vect_set_dump_settings ();
- compute_immediate_uses (TDFA_USE_OPS, need_imm_uses_for);
+ /* Allocate the bitmap that records which virtual variables that
+ need to be renamed. */
+ vect_vnames_to_rename = BITMAP_ALLOC (NULL);
/* ----------- Analyze loops. ----------- */
/* If some loop was duplicated, it gets bigger number
than all previously defined loops. This fact allows us to run
only over initial loops skipping newly generated ones. */
- loops_num = loops->num;
- for (i = 1; i < loops_num; i++)
+ vect_loops_num = loops->num;
+ for (i = 1; i < vect_loops_num; i++)
{
loop_vec_info loop_vinfo;
struct loop *loop = loops->parray[i];
if (!loop)
continue;
+ vect_loop_location = find_loop_location (loop);
loop_vinfo = vect_analyze_loop (loop);
loop->aux = loop_vinfo;
if (!loop_vinfo || !LOOP_VINFO_VECTORIZABLE_P (loop_vinfo))
continue;
- vect_transform_loop (loop_vinfo, loops);
+ vect_transform_loop (loop_vinfo, loops);
num_vectorized_loops++;
}
+ vect_loop_location = UNKNOWN_LOC;
- if (vect_debug_stats (NULL) || vect_debug_details (NULL))
- fprintf (dump_file, "\nvectorized %u loops in function.\n",
+ if (vect_print_dump_info (REPORT_VECTORIZED_LOOPS))
+ fprintf (vect_dump, "vectorized %u loops in function.\n",
num_vectorized_loops);
/* ----------- Finalize. ----------- */
- free_df ();
- for (i = 1; i < loops_num; i++)
+ BITMAP_FREE (vect_vnames_to_rename);
+
+ for (i = 1; i < vect_loops_num; i++)
{
struct loop *loop = loops->parray[i];
loop_vec_info loop_vinfo;
destroy_loop_vec_info (loop_vinfo);
loop->aux = NULL;
}
-
- rewrite_into_ssa (false);
- if (!bitmap_empty_p (vars_to_rename))
- {
- /* The rewrite of ssa names may cause violation of loop closed ssa
- form invariants. TODO -- avoid these rewrites completely.
- Information in virtual phi nodes is sufficient for it. */
- rewrite_into_loop_closed_ssa ();
- }
- rewrite_into_loop_closed_ssa ();
- bitmap_clear (vars_to_rename);
}