/* Rewrite a program in Normal form into SSA.
- Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
+ Free Software Foundation, Inc.
Contributed by Diego Novillo <dnovillo@redhat.com>
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
+the Free Software Foundation; either version 3, or (at your option)
any later version.
GCC is distributed in the hope that it will be useful,
GNU General Public License for more details.
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, 51 Franklin Street, Fifth Floor,
-Boston, MA 02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "tm.h"
#include "tree.h"
#include "flags.h"
-#include "rtl.h"
#include "tm_p.h"
#include "langhooks.h"
-#include "hard-reg-set.h"
#include "basic-block.h"
#include "output.h"
-#include "expr.h"
#include "function.h"
-#include "diagnostic.h"
+#include "tree-pretty-print.h"
+#include "gimple-pretty-print.h"
#include "bitmap.h"
#include "tree-flow.h"
-#include "tree-gimple.h"
+#include "gimple.h"
#include "tree-inline.h"
-#include "varray.h"
#include "timevar.h"
#include "hashtab.h"
#include "tree-dump.h"
#include "tree-pass.h"
#include "cfgloop.h"
#include "domwalk.h"
-#include "ggc.h"
#include "params.h"
#include "vecprim.h"
+
/* This file builds the SSA form for a function as described in:
R. Cytron, J. Ferrante, B. Rosen, M. Wegman, and K. Zadeck. Efficiently
Computing Static Single Assignment Form and the Control Dependence
Graph. ACM Transactions on Programming Languages and Systems,
13(4):451-490, October 1991. */
-/* True if the code is in ssa form. */
-bool in_ssa_p;
-
/* Structure to map a variable VAR to the set of blocks that contain
definitions for VAR. */
struct def_blocks_d
state after completing rewriting of a block and its dominator
children. Its elements have the following properties:
- - An SSA_NAME indicates that the current definition of the
- underlying variable should be set to the given SSA_NAME.
+ - An SSA_NAME (N) indicates that the current definition of the
+ underlying variable should be set to the given SSA_NAME. If the
+ symbol associated with the SSA_NAME is not a GIMPLE register, the
+ next slot in the stack must be a _DECL node (SYM). In this case,
+ the name N in the previous slot is the current reaching
+ definition for SYM.
- A _DECL node indicates that the underlying variable has no
current definition.
- - A NULL node is used to mark the last node associated with the
- current block.
-
- - A NULL node at the top entry is used to mark the last node
+ - A NULL node at the top entry is used to mark the last slot
associated with the current block. */
static VEC(tree,heap) *block_defs_stack;
+
/* Set of existing SSA names being replaced by update_ssa. */
static sbitmap old_ssa_names;
the operations done on them are presence tests. */
static sbitmap new_ssa_names;
-/* Symbols whose SSA form needs to be updated or created for the first
- time. */
-static bitmap syms_to_rename;
+sbitmap interesting_blocks;
/* Set of SSA names that have been marked to be released after they
were registered in the replacement table. They will be finally
released after we finish updating the SSA web. */
static bitmap names_to_release;
-/* For each block, the phi nodes that need to be rewritten are stored into
- these vectors. */
-
-typedef VEC(tree, heap) *tree_vec;
-DEF_VEC_P (tree_vec);
-DEF_VEC_ALLOC_P (tree_vec, heap);
-
-static VEC(tree_vec, heap) *phis_to_rewrite;
+static VEC(gimple_vec, heap) *phis_to_rewrite;
/* The bitmap of non-NULL elements of PHIS_TO_REWRITE. */
-
static bitmap blocks_with_phis_to_rewrite;
/* Growth factor for NEW_SSA_NAMES and OLD_SSA_NAMES. These sets need
bitmap set;
};
+
/* NEW -> OLD_SET replacement table. If we are replacing several
existing SSA names O_1, O_2, ..., O_j with a new name N_i,
then REPL_TBL[N_i] = { O_1, O_2, ..., O_j }. */
static htab_t repl_tbl;
-/* true if register_new_name_mapping needs to initialize the data
- structures needed by update_ssa. */
-static bool need_to_initialize_update_ssa_p = true;
-
-/* true if update_ssa needs to update virtual operands. */
-static bool need_to_update_vops_p = false;
+/* The function the SSA updating data structures have been initialized for.
+ NULL if they need to be initialized by register_new_name_mapping. */
+static struct function *update_ssa_initialized_fn = NULL;
/* Statistics kept by update_ssa to use in the virtual mapping
heuristic. If the number of virtual mappings is beyond certain
/* This bitmap contains the variables which are set before they
are used in a basic block. */
bitmap kills;
-
- /* Bitmap of names to rename. */
- sbitmap names_to_rename;
-
- /* Set of blocks that mark_def_sites deems interesting for the
- renamer to process. */
- sbitmap interesting_blocks;
};
/* Information stored for SSA names. */
struct ssa_name_info
{
- /* The actual definition of the ssa name. */
+ /* The current reaching definition replacing this SSA name. */
tree current_def;
/* This field indicates whether or not the variable may need PHI nodes.
ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
/* Age of this record (so that info_for_ssa_name table can be cleared
- quicky); if AGE < CURRENT_INFO_FOR_SSA_NAME_AGE, then the fields
+ quickly); if AGE < CURRENT_INFO_FOR_SSA_NAME_AGE, then the fields
are assumed to be null. */
unsigned age;
};
static unsigned current_info_for_ssa_name_age;
/* The set of blocks affected by update_ssa. */
-
static bitmap blocks_to_update;
/* The main entry point to the SSA renamer (rewrite_blocks) may be
};
-/* Use TREE_VISITED to keep track of which statements we want to
- rename. When renaming a subset of the variables, not all
- statements will be processed. This is decided in mark_def_sites. */
-#define REWRITE_THIS_STMT(T) TREE_VISITED (T)
-
-/* Use the unsigned flag to keep track of which statements we want to
- visit when marking new definition sites. This is slightly
- different than REWRITE_THIS_STMT: it's used by update_ssa to
- distinguish statements that need to have both uses and defs
- processed from those that only need to have their defs processed.
- Statements that define new SSA names only need to have their defs
- registered, but they don't need to have their uses renamed. */
-#define REGISTER_DEFS_IN_THIS_STMT(T) (T)->common.unsigned_flag
/* Prototypes for debugging functions. */
extern void debug_def_blocks (void);
extern void dump_tree_ssa_stats (FILE *);
extern void debug_tree_ssa_stats (void);
-void dump_update_ssa (FILE *);
-void debug_update_ssa (void);
-void dump_names_replaced_by (FILE *, tree);
-void debug_names_replaced_by (tree);
+extern void dump_update_ssa (FILE *);
+extern void debug_update_ssa (void);
+extern void dump_names_replaced_by (FILE *, tree);
+extern void debug_names_replaced_by (tree);
+extern void dump_def_blocks (FILE *);
+extern void debug_def_blocks (void);
+extern void dump_defs_stack (FILE *, int);
+extern void debug_defs_stack (int);
+extern void dump_currdefs (FILE *);
+extern void debug_currdefs (void);
+
+/* Return true if STMT needs to be rewritten. When renaming a subset
+ of the variables, not all statements will be processed. This is
+ decided in mark_def_sites. */
+
+static inline bool
+rewrite_uses_p (gimple stmt)
+{
+ return gimple_visited_p (stmt);
+}
+
+
+/* Set the rewrite marker on STMT to the value given by REWRITE_P. */
+
+static inline void
+set_rewrite_uses (gimple stmt, bool rewrite_p)
+{
+ gimple_set_visited (stmt, rewrite_p);
+}
+
+
+/* Return true if the DEFs created by statement STMT should be
+ registered when marking new definition sites. This is slightly
+ different than rewrite_uses_p: it's used by update_ssa to
+ distinguish statements that need to have both uses and defs
+ processed from those that only need to have their defs processed.
+ Statements that define new SSA names only need to have their defs
+ registered, but they don't need to have their uses renamed. */
+
+static inline bool
+register_defs_p (gimple stmt)
+{
+ return gimple_plf (stmt, GF_PLF_1) != 0;
+}
+
+
+/* If REGISTER_DEFS_P is true, mark STMT to have its DEFs registered. */
+
+static inline void
+set_register_defs (gimple stmt, bool register_defs_p)
+{
+ gimple_set_plf (stmt, GF_PLF_1, register_defs_p);
+}
+
/* Get the information associated with NAME. */
-static inline struct ssa_name_info *
+static inline ssa_name_info_p
get_ssa_name_ann (tree name)
{
unsigned ver = SSA_NAME_VERSION (name);
info = VEC_index (ssa_name_info_p, info_for_ssa_name, ver);
if (info->age < current_info_for_ssa_name_age)
{
- info->need_phi_state = 0;
+ info->need_phi_state = NEED_PHI_STATE_UNKNOWN;
info->current_def = NULL_TREE;
info->age = current_info_for_ssa_name_age;
}
return info;
}
-/* Clears info for ssa names. */
+
+/* Clears info for SSA names. */
static void
clear_ssa_name_info (void)
current_info_for_ssa_name_age++;
}
-/* Gets phi_state field for VAR. */
+
+/* Get phi_state field for VAR. */
static inline enum need_phi_state
get_phi_state (tree var)
}
-/* Compute global livein information given the set of blockx where
+/* Compute global livein information given the set of blocks where
an object is locally live at the start of the block (LIVEIN)
and the set of blocks where the object is defined (DEF_BLOCKS).
for LIVEIN). */
void
-compute_global_livein (bitmap livein, bitmap def_blocks)
+compute_global_livein (bitmap livein ATTRIBUTE_UNUSED, bitmap def_blocks ATTRIBUTE_UNUSED)
{
basic_block bb, *worklist, *tos;
unsigned i;
= (basic_block *) xmalloc (sizeof (basic_block) * (last_basic_block + 1));
EXECUTE_IF_SET_IN_BITMAP (livein, 0, i, bi)
- {
- *tos++ = BASIC_BLOCK (i);
- }
+ *tos++ = BASIC_BLOCK (i);
/* Iterate until the worklist is empty. */
while (tos != worklist)
static void
initialize_flags_in_bb (basic_block bb)
{
- tree phi, stmt;
- block_stmt_iterator bsi;
+ gimple stmt;
+ gimple_stmt_iterator gsi;
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+ for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
- REWRITE_THIS_STMT (phi) = 0;
- REGISTER_DEFS_IN_THIS_STMT (phi) = 0;
+ gimple phi = gsi_stmt (gsi);
+ set_rewrite_uses (phi, false);
+ set_register_defs (phi, false);
}
- for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
- stmt = bsi_stmt (bsi);
+ stmt = gsi_stmt (gsi);
+
/* We are going to use the operand cache API, such as
SET_USE, SET_DEF, and FOR_EACH_IMM_USE_FAST. The operand
cache for each statement should be up-to-date. */
- gcc_assert (!stmt_modified_p (stmt));
- REWRITE_THIS_STMT (stmt) = 0;
- REGISTER_DEFS_IN_THIS_STMT (stmt) = 0;
+ gcc_assert (!gimple_modified_p (stmt));
+ set_rewrite_uses (stmt, false);
+ set_register_defs (stmt, false);
}
}
mark_block_for_update (basic_block bb)
{
gcc_assert (blocks_to_update != NULL);
- if (bitmap_bit_p (blocks_to_update, bb->index))
+ if (!bitmap_set_bit (blocks_to_update, bb->index))
return;
- bitmap_set_bit (blocks_to_update, bb->index);
initialize_flags_in_bb (bb);
}
/* Return true if symbol SYM is marked for renaming. */
-static inline bool
+bool
symbol_marked_for_renaming (tree sym)
{
- gcc_assert (DECL_P (sym));
- return bitmap_bit_p (syms_to_rename, DECL_UID (sym));
+ return bitmap_bit_p (SYMS_TO_RENAME (cfun), DECL_UID (sym));
}
is_old_name (tree name)
{
unsigned ver = SSA_NAME_VERSION (name);
+ if (!new_ssa_names)
+ return false;
return ver < new_ssa_names->n_bits && TEST_BIT (old_ssa_names, ver);
}
is_new_name (tree name)
{
unsigned ver = SSA_NAME_VERSION (name);
+ if (!new_ssa_names)
+ return false;
return ver < new_ssa_names->n_bits && TEST_BIT (new_ssa_names, ver);
}
}
-/* Return the names replaced by NEW (i.e., REPL_TBL[NEW].SET). */
+/* Return the names replaced by NEW_TREE (i.e., REPL_TBL[NEW_TREE].SET). */
static inline bitmap
-names_replaced_by (tree new)
+names_replaced_by (tree new_tree)
{
struct repl_map_d m;
void **slot;
- m.name = new;
+ m.name = new_tree;
slot = htab_find_slot (repl_tbl, (void *) &m, NO_INSERT);
/* If N was not registered in the replacement table, return NULL. */
}
-/* Add OLD to REPL_TBL[NEW].SET. */
+/* Add OLD to REPL_TBL[NEW_TREE].SET. */
static inline void
-add_to_repl_tbl (tree new, tree old)
+add_to_repl_tbl (tree new_tree, tree old)
{
struct repl_map_d m, *mp;
void **slot;
- m.name = new;
+ m.name = new_tree;
slot = htab_find_slot (repl_tbl, (void *) &m, INSERT);
if (*slot == NULL)
{
mp = XNEW (struct repl_map_d);
- mp->name = new;
+ mp->name = new_tree;
mp->set = BITMAP_ALLOC (NULL);
*slot = (void *) mp;
}
}
-/* Add a new mapping NEW -> OLD REPL_TBL. Every entry N_i in REPL_TBL
+/* Add a new mapping NEW_TREE -> OLD REPL_TBL. Every entry N_i in REPL_TBL
represents the set of names O_1 ... O_j replaced by N_i. This is
used by update_ssa and its helpers to introduce new SSA names in an
already formed SSA web. */
static void
-add_new_name_mapping (tree new, tree old)
+add_new_name_mapping (tree new_tree, tree old)
{
timevar_push (TV_TREE_SSA_INCREMENTAL);
- /* OLD and NEW must be different SSA names for the same symbol. */
- gcc_assert (new != old && SSA_NAME_VAR (new) == SSA_NAME_VAR (old));
-
- /* We may need to grow NEW_SSA_NAMES and OLD_SSA_NAMES because our
- caller may have created new names since the set was created. */
- if (new_ssa_names->n_bits <= num_ssa_names - 1)
- {
- unsigned int new_sz = num_ssa_names + NAME_SETS_GROWTH_FACTOR;
- new_ssa_names = sbitmap_resize (new_ssa_names, new_sz, 0);
- old_ssa_names = sbitmap_resize (old_ssa_names, new_sz, 0);
- }
+ /* OLD and NEW_TREE must be different SSA names for the same symbol. */
+ gcc_assert (new_tree != old && SSA_NAME_VAR (new_tree) == SSA_NAME_VAR (old));
/* If this mapping is for virtual names, we will need to update
- virtual operands. */
- if (!is_gimple_reg (new))
+ virtual operands. If this is a mapping for .MEM, then we gather
+ the symbols associated with each name. */
+ if (!is_gimple_reg (new_tree))
{
tree sym;
- size_t uid;
- need_to_update_vops_p = true;
+ update_ssa_stats.num_virtual_mappings++;
+ update_ssa_stats.num_virtual_symbols++;
/* Keep counts of virtual mappings and symbols to use in the
virtual mapping heuristic. If we have large numbers of
will make more sense to rename the symbols from scratch.
Otherwise, the insertion of PHI nodes for each of the old
names in these mappings will be very slow. */
- sym = SSA_NAME_VAR (new);
- uid = DECL_UID (sym);
- update_ssa_stats.num_virtual_mappings++;
- if (!bitmap_bit_p (update_ssa_stats.virtual_symbols, uid))
- {
- bitmap_set_bit (update_ssa_stats.virtual_symbols, uid);
- update_ssa_stats.num_virtual_symbols++;
- }
+ sym = SSA_NAME_VAR (new_tree);
+ bitmap_set_bit (update_ssa_stats.virtual_symbols, DECL_UID (sym));
+ }
+
+ /* We may need to grow NEW_SSA_NAMES and OLD_SSA_NAMES because our
+ caller may have created new names since the set was created. */
+ if (new_ssa_names->n_bits <= num_ssa_names - 1)
+ {
+ unsigned int new_sz = num_ssa_names + NAME_SETS_GROWTH_FACTOR;
+ new_ssa_names = sbitmap_resize (new_ssa_names, new_sz, 0);
+ old_ssa_names = sbitmap_resize (old_ssa_names, new_sz, 0);
}
/* Update the REPL_TBL table. */
- add_to_repl_tbl (new, old);
+ add_to_repl_tbl (new_tree, old);
/* If OLD had already been registered as a new name, then all the
- names that OLD replaces should also be replaced by NEW. */
+ names that OLD replaces should also be replaced by NEW_TREE. */
if (is_new_name (old))
- bitmap_ior_into (names_replaced_by (new), names_replaced_by (old));
+ bitmap_ior_into (names_replaced_by (new_tree), names_replaced_by (old));
- /* Register NEW and OLD in NEW_SSA_NAMES and OLD_SSA_NAMES,
+ /* Register NEW_TREE and OLD in NEW_SSA_NAMES and OLD_SSA_NAMES,
respectively. */
- SET_BIT (new_ssa_names, SSA_NAME_VERSION (new));
+ SET_BIT (new_ssa_names, SSA_NAME_VERSION (new_tree));
SET_BIT (old_ssa_names, SSA_NAME_VERSION (old));
/* Update mapping counter to use in the virtual mapping heuristic. */
BB:
1- Variables defined by S in the DEFS of S are marked in the bitmap
- WALK_DATA->GLOBAL_DATA->KILLS.
+ KILLS.
2- If S uses a variable VAR and there is no preceding kill of VAR,
then it is marked in the LIVEIN_BLOCKS bitmap associated with VAR.
we create. */
static void
-mark_def_sites (struct dom_walk_data *walk_data,
- basic_block bb,
- block_stmt_iterator bsi)
-{
- struct mark_def_sites_global_data *gd =
- (struct mark_def_sites_global_data *) walk_data->global_data;
- bitmap kills = gd->kills;
- tree stmt, def;
+mark_def_sites (basic_block bb, gimple stmt, bitmap kills)
+{
+ tree def;
use_operand_p use_p;
- def_operand_p def_p;
ssa_op_iter iter;
- stmt = bsi_stmt (bsi);
- update_stmt_if_modified (stmt);
+ /* Since this is the first time that we rewrite the program into SSA
+ form, force an operand scan on every statement. */
+ update_stmt (stmt);
gcc_assert (blocks_to_update == NULL);
- REGISTER_DEFS_IN_THIS_STMT (stmt) = 0;
- REWRITE_THIS_STMT (stmt) = 0;
+ set_register_defs (stmt, false);
+ set_rewrite_uses (stmt, false);
+
+ if (is_gimple_debug (stmt))
+ {
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
+ {
+ tree sym = USE_FROM_PTR (use_p);
+ gcc_assert (DECL_P (sym));
+ set_rewrite_uses (stmt, true);
+ }
+ if (rewrite_uses_p (stmt))
+ SET_BIT (interesting_blocks, bb->index);
+ return;
+ }
/* If a variable is used before being set, then the variable is live
across a block boundary, so mark it live-on-entry to BB. */
- FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter,
- SSA_OP_USE | SSA_OP_VUSE | SSA_OP_VMUSTKILL)
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
{
tree sym = USE_FROM_PTR (use_p);
gcc_assert (DECL_P (sym));
if (!bitmap_bit_p (kills, DECL_UID (sym)))
set_livein_block (sym, bb);
- REWRITE_THIS_STMT (stmt) = 1;
- }
-
- /* Note that virtual definitions are irrelevant for computing KILLS
- because a V_MAY_DEF does not constitute a killing definition of the
- variable. However, the operand of a virtual definitions is a use
- of the variable, so it may cause the variable to be considered
- live-on-entry. */
- FOR_EACH_SSA_MAYDEF_OPERAND (def_p, use_p, stmt, iter)
- {
- tree sym = USE_FROM_PTR (use_p);
- gcc_assert (DECL_P (sym));
- set_livein_block (sym, bb);
- set_def_block (sym, bb, false);
- REGISTER_DEFS_IN_THIS_STMT (stmt) = 1;
- REWRITE_THIS_STMT (stmt) = 1;
+ set_rewrite_uses (stmt, true);
}
- /* Now process the defs and must-defs made by this statement. */
- FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_DEF | SSA_OP_VMUSTDEF)
+ /* Now process the defs. Mark BB as the definition block and add
+ each def to the set of killed symbols. */
+ FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_DEF)
{
gcc_assert (DECL_P (def));
set_def_block (def, bb, false);
bitmap_set_bit (kills, DECL_UID (def));
- REGISTER_DEFS_IN_THIS_STMT (stmt) = 1;
+ set_register_defs (stmt, true);
}
/* If we found the statement interesting then also mark the block BB
as interesting. */
- if (REWRITE_THIS_STMT (stmt) || REGISTER_DEFS_IN_THIS_STMT (stmt))
- SET_BIT (gd->interesting_blocks, bb->index);
+ if (rewrite_uses_p (stmt) || register_defs_p (stmt))
+ SET_BIT (interesting_blocks, bb->index);
}
/* Structure used by prune_unused_phi_nodes to record bounds of the intervals
static int
cmp_dfsnum (const void *a, const void *b)
{
- const struct dom_dfsnum *da = a;
- const struct dom_dfsnum *db = b;
+ const struct dom_dfsnum *const da = (const struct dom_dfsnum *) a;
+ const struct dom_dfsnum *const db = (const struct dom_dfsnum *) b;
return (int) da->dfs_num - (int) db->dfs_num;
}
then for each of them find the nearest def that dominates them. If this
def is a phi node, we mark it live, and if it was not live before, we
add the predecessors of its basic block to the worklist.
-
+
To quickly locate the nearest def that dominates use, we use dfs numbering
of the dominance tree (that is already available in order to speed up
queries). For each def, we have the interval given by the dfs number on
}
/* If the phi node is already live, there is nothing to do. */
- if (bitmap_bit_p (live_phis, p))
+ if (!bitmap_set_bit (live_phis, p))
continue;
- /* Mark the phi as live, and add the new uses to the worklist. */
- bitmap_set_bit (live_phis, p);
+ /* Add the new uses to the worklist. */
def_bb = BASIC_BLOCK (p);
FOR_EACH_EDGE (e, ei, def_bb->preds)
{
free (defs);
}
-/* Given a set of blocks with variable definitions (DEF_BLOCKS),
- return a bitmap with all the blocks in the iterated dominance
- frontier of the blocks in DEF_BLOCKS. DFS contains dominance
- frontier information as returned by compute_dominance_frontiers.
-
- The resulting set of blocks are the potential sites where PHI nodes
- are needed. The caller is responsible from freeing the memory
- allocated for the return value. */
-
-static bitmap
-find_idf (bitmap def_blocks, bitmap *dfs)
-{
- bitmap_iterator bi;
- unsigned bb_index;
- VEC(int,heap) *work_stack;
- bitmap phi_insertion_points;
-
- work_stack = VEC_alloc (int, heap, n_basic_blocks);
- phi_insertion_points = BITMAP_ALLOC (NULL);
-
- /* Seed the work list with all the blocks in DEF_BLOCKS. */
- EXECUTE_IF_SET_IN_BITMAP (def_blocks, 0, bb_index, bi)
- /* We use VEC_quick_push here for speed. This is safe because we
- know that the number of definition blocks is no greater than
- the number of basic blocks, which is the initial capacity of
- WORK_STACK. */
- VEC_quick_push (int, work_stack, bb_index);
-
- /* Pop a block off the worklist, add every block that appears in
- the original block's DF that we have not already processed to
- the worklist. Iterate until the worklist is empty. Blocks
- which are added to the worklist are potential sites for
- PHI nodes. */
- while (VEC_length (int, work_stack) > 0)
- {
- bb_index = VEC_pop (int, work_stack);
-
- /* Since the registration of NEW -> OLD name mappings is done
- separately from the call to update_ssa, when updating the SSA
- form, the basic blocks where new and/or old names are defined
- may have disappeared by CFG cleanup calls. In this case,
- we may pull a non-existing block from the work stack. */
- gcc_assert (bb_index < (unsigned) last_basic_block);
-
- EXECUTE_IF_AND_COMPL_IN_BITMAP (dfs[bb_index], phi_insertion_points,
- 0, bb_index, bi)
- {
- /* Use a safe push because if there is a definition of VAR
- in every basic block, then WORK_STACK may eventually have
- more than N_BASIC_BLOCK entries. */
- VEC_safe_push (int, heap, work_stack, bb_index);
- bitmap_set_bit (phi_insertion_points, bb_index);
- }
- }
-
- VEC_free (int, heap, work_stack);
-
- return phi_insertion_points;
-}
-
-
/* Return the set of blocks where variable VAR is defined and the blocks
where VAR is live on entry (livein). Return NULL, if no entry is
found in DEF_BLOCKS. */
static inline tree
get_default_def_for (tree sym)
{
- tree ddef = default_def (sym);
+ tree ddef = gimple_default_def (cfun, sym);
if (ddef == NULL_TREE)
{
- ddef = make_ssa_name (sym, build_empty_stmt ());
+ ddef = make_ssa_name (sym, gimple_build_nop ());
set_default_def (sym, ddef);
}
/* Marks phi node PHI in basic block BB for rewrite. */
static void
-mark_phi_for_rewrite (basic_block bb, tree phi)
+mark_phi_for_rewrite (basic_block bb, gimple phi)
{
- tree_vec phis;
+ gimple_vec phis;
unsigned i, idx = bb->index;
- if (REWRITE_THIS_STMT (phi))
+ if (rewrite_uses_p (phi))
return;
- REWRITE_THIS_STMT (phi) = 1;
+
+ set_rewrite_uses (phi, true);
if (!blocks_with_phis_to_rewrite)
return;
bitmap_set_bit (blocks_with_phis_to_rewrite, idx);
- VEC_reserve (tree_vec, heap, phis_to_rewrite, last_basic_block + 1);
- for (i = VEC_length (tree_vec, phis_to_rewrite); i <= idx; i++)
- VEC_quick_push (tree_vec, phis_to_rewrite, NULL);
+ VEC_reserve (gimple_vec, heap, phis_to_rewrite, last_basic_block + 1);
+ for (i = VEC_length (gimple_vec, phis_to_rewrite); i <= idx; i++)
+ VEC_quick_push (gimple_vec, phis_to_rewrite, NULL);
- phis = VEC_index (tree_vec, phis_to_rewrite, idx);
+ phis = VEC_index (gimple_vec, phis_to_rewrite, idx);
if (!phis)
- phis = VEC_alloc (tree, heap, 10);
+ phis = VEC_alloc (gimple, heap, 10);
- VEC_safe_push (tree, heap, phis, phi);
- VEC_replace (tree_vec, phis_to_rewrite, idx, phis);
+ VEC_safe_push (gimple, heap, phis, phi);
+ VEC_replace (gimple_vec, phis_to_rewrite, idx, phis);
}
/* Insert PHI nodes for variable VAR using the iterated dominance
frontier given in PHI_INSERTION_POINTS. If UPDATE_P is true, this
- function assumes that the caller is incrementally updating the SSA
- form, in which case (1) VAR is assumed to be an SSA name, (2) a new
- SSA name is created for VAR's symbol, and, (3) all the arguments
- for the newly created PHI node are set to VAR.
+ function assumes that the caller is incrementally updating the
+ existing SSA form, in which case VAR may be an SSA name instead of
+ a symbol.
PHI_INSERTION_POINTS is updated to reflect nodes that already had a
PHI node for VAR. On exit, only the nodes that received a PHI node
{
unsigned bb_index;
edge e;
- tree phi;
+ gimple phi;
basic_block bb;
bitmap_iterator bi;
struct def_blocks_d *def_map;
if (update_p)
mark_block_for_update (bb);
- if (update_p && TREE_CODE (var) == SSA_NAME)
+ phi = NULL;
+
+ if (TREE_CODE (var) == SSA_NAME)
{
/* If we are rewriting SSA names, create the LHS of the PHI
node by duplicating VAR. This is useful in the case of
edge_iterator ei;
tree new_lhs;
+ gcc_assert (update_p);
phi = create_phi_node (var, bb);
+
new_lhs = duplicate_ssa_name (var, phi);
- SET_PHI_RESULT (phi, new_lhs);
+ gimple_phi_set_result (phi, new_lhs);
add_new_name_mapping (new_lhs, var);
/* Add VAR to every argument slot of PHI. We need VAR in
renamer will use the symbol on the LHS to get its
reaching definition. */
FOR_EACH_EDGE (e, ei, bb->preds)
- add_phi_arg (phi, var, e);
+ add_phi_arg (phi, var, e, UNKNOWN_LOCATION);
}
else
{
- tree sym = DECL_P (var) ? var : SSA_NAME_VAR (var);
- phi = create_phi_node (sym, bb);
+ tree tracked_var;
+
+ gcc_assert (DECL_P (var));
+ phi = create_phi_node (var, bb);
+
+ tracked_var = target_for_debug_bind (var);
+ if (tracked_var)
+ {
+ gimple note = gimple_build_debug_bind (tracked_var,
+ PHI_RESULT (phi),
+ phi);
+ gimple_stmt_iterator si = gsi_after_labels (bb);
+ gsi_insert_before (&si, note, GSI_SAME_STMT);
+ }
}
/* Mark this PHI node as interesting for update_ssa. */
- REGISTER_DEFS_IN_THIS_STMT (phi) = 1;
+ set_register_defs (phi, true);
mark_phi_for_rewrite (bb, phi);
}
}
/* Insert PHI nodes at the dominance frontier of blocks with variable
definitions. DFS contains the dominance frontier information for
- the flowgraph. PHI nodes will only be inserted at the dominance
- frontier of definition blocks for variables whose NEED_PHI_STATE
- annotation is marked as ``maybe'' or ``unknown'' (computed by
- mark_def_sites). */
+ the flowgraph. */
static void
-insert_phi_nodes (bitmap *dfs)
+insert_phi_nodes (bitmap_head *dfs)
{
referenced_var_iterator rvi;
+ bitmap_iterator bi;
tree var;
+ bitmap vars;
+ unsigned uid;
timevar_push (TV_TREE_INSERT_PHI_NODES);
-
- FOR_EACH_REFERENCED_VAR (var, rvi)
+
+ /* Do two stages to avoid code generation differences for UID
+ differences but no UID ordering differences. */
+
+ vars = BITMAP_ALLOC (NULL);
+ FOR_EACH_REFERENCED_VAR (cfun, var, rvi)
{
struct def_blocks_d *def_map;
- bitmap idf;
def_map = find_def_blocks_for (var);
if (def_map == NULL)
continue;
if (get_phi_state (var) != NEED_PHI_STATE_NO)
- {
- idf = find_idf (def_map->def_blocks, dfs);
- insert_phi_nodes_for (var, idf, false);
- BITMAP_FREE (idf);
- }
+ bitmap_set_bit (vars, DECL_UID (var));
}
+ EXECUTE_IF_SET_IN_BITMAP (vars, 0, uid, bi)
+ {
+ tree var = referenced_var (uid);
+ struct def_blocks_d *def_map;
+ bitmap idf;
+
+ def_map = find_def_blocks_for (var);
+ idf = compute_idf (def_map->def_blocks, dfs);
+ insert_phi_nodes_for (var, idf, false);
+ BITMAP_FREE (idf);
+ }
+
+ BITMAP_FREE (vars);
+
timevar_pop (TV_TREE_INSERT_PHI_NODES);
}
-/* Register DEF (an SSA_NAME) to be a new definition for its underlying
- variable (SSA_NAME_VAR (DEF)) and push VAR's current reaching definition
- into the stack pointed to by BLOCK_DEFS_P. */
+/* Push SYM's current reaching definition into BLOCK_DEFS_STACK and
+ register DEF (an SSA_NAME) to be a new definition for SYM. */
-void
-register_new_def (tree def, VEC(tree,heap) **block_defs_p)
+static void
+register_new_def (tree def, tree sym)
{
- tree var = SSA_NAME_VAR (def);
tree currdef;
-
+
/* If this variable is set in a single basic block and all uses are
dominated by the set(s) in that single basic block, then there is
no reason to record anything for this variable in the block local
This is the same test to prune the set of variables which may
need PHI nodes. So we just use that information since it's already
computed and available for us to use. */
- if (get_phi_state (var) == NEED_PHI_STATE_NO)
+ if (get_phi_state (sym) == NEED_PHI_STATE_NO)
{
- set_current_def (var, def);
+ set_current_def (sym, def);
return;
}
- currdef = get_current_def (var);
+ currdef = get_current_def (sym);
- /* Push the current reaching definition into *BLOCK_DEFS_P. This stack is
- later used by the dominator tree callbacks to restore the reaching
- definitions for all the variables defined in the block after a recursive
- visit to all its immediately dominated blocks. If there is no current
- reaching definition, then just record the underlying _DECL node. */
- VEC_safe_push (tree, heap, *block_defs_p, currdef ? currdef : var);
+ /* If SYM is not a GIMPLE register, then CURRDEF may be a name whose
+ SSA_NAME_VAR is not necessarily SYM. In this case, also push SYM
+ in the stack so that we know which symbol is being defined by
+ this SSA name when we unwind the stack. */
+ if (currdef && !is_gimple_reg (sym))
+ VEC_safe_push (tree, heap, block_defs_stack, sym);
- /* Set the current reaching definition for VAR to be DEF. */
- set_current_def (var, def);
+ /* Push the current reaching definition into BLOCK_DEFS_STACK. This
+ stack is later used by the dominator tree callbacks to restore
+ the reaching definitions for all the variables defined in the
+ block after a recursive visit to all its immediately dominated
+ blocks. If there is no current reaching definition, then just
+ record the underlying _DECL node. */
+ VEC_safe_push (tree, heap, block_defs_stack, currdef ? currdef : sym);
+
+ /* Set the current reaching definition for SYM to be DEF. */
+ set_current_def (sym, def);
}
2- Every statement in BB is rewritten. USE and VUSE operands are
rewritten with their corresponding reaching definition. DEF and
VDEF targets are registered as new definitions.
-
+
3- All the PHI nodes in successor blocks of BB are visited. The
argument corresponding to BB is replaced with its current reaching
definition.
definitions are restored to the names that were valid in the
dominator parent of BB. */
-/* SSA Rewriting Step 1. Initialization, create a block local stack
- of reaching definitions for new SSA names produced in this block
- (BLOCK_DEFS). Register new definitions for every PHI node in the
- block. */
-
-static void
-rewrite_initialize_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb)
-{
- tree phi;
-
- if (dump_file && (dump_flags & TDF_DETAILS))
- fprintf (dump_file, "\n\nRenaming block #%d\n\n", bb->index);
-
- /* Mark the unwind point for this block. */
- VEC_safe_push (tree, heap, block_defs_stack, NULL_TREE);
-
- /* Step 1. Register new definitions for every PHI node in the block.
- Conceptually, all the PHI nodes are executed in parallel and each PHI
- node introduces a new version for the associated variable. */
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- {
- tree result = PHI_RESULT (phi);
- register_new_def (result, &block_defs_stack);
- }
-}
-
-
/* Return the current definition for variable VAR. If none is found,
- create a new SSA name to act as the zeroth definition for VAR. If VAR
- is call clobbered and there exists a more recent definition of
- GLOBAL_VAR, return the definition for GLOBAL_VAR. This means that VAR
- has been clobbered by a function call since its last assignment. */
+ create a new SSA name to act as the zeroth definition for VAR. */
static tree
get_reaching_def (tree var)
{
- tree currdef_var, avar;
-
+ tree currdef;
+
/* Lookup the current reaching definition for VAR. */
- currdef_var = get_current_def (var);
+ currdef = get_current_def (var);
/* If there is no reaching definition for VAR, create and register a
default definition for it (if needed). */
- if (currdef_var == NULL_TREE)
+ if (currdef == NULL_TREE)
{
- avar = DECL_P (var) ? var : SSA_NAME_VAR (var);
- currdef_var = get_default_def_for (avar);
- set_current_def (var, currdef_var);
+ tree sym = DECL_P (var) ? var : SSA_NAME_VAR (var);
+ currdef = get_default_def_for (sym);
+ set_current_def (var, currdef);
}
/* Return the current reaching definition for VAR, or the default
definition, if we had to create one. */
- return currdef_var;
+ return currdef;
}
+/* Helper function for rewrite_stmt. Rewrite uses in a debug stmt. */
+
+static void
+rewrite_debug_stmt_uses (gimple stmt)
+{
+ use_operand_p use_p;
+ ssa_op_iter iter;
+ bool update = false;
+
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
+ {
+ tree var = USE_FROM_PTR (use_p), def = NULL_TREE;
+ gcc_assert (DECL_P (var));
+ if (var_ann (var) == NULL)
+ {
+ if (TREE_CODE (var) == PARM_DECL && single_succ_p (ENTRY_BLOCK_PTR))
+ {
+ gimple_stmt_iterator gsi
+ = gsi_after_labels (single_succ (ENTRY_BLOCK_PTR));
+ int lim;
+ /* Search a few source bind stmts at the start of first bb to
+ see if a DEBUG_EXPR_DECL can't be reused. */
+ for (lim = 32;
+ !gsi_end_p (gsi) && lim > 0;
+ gsi_next (&gsi), lim--)
+ {
+ gimple gstmt = gsi_stmt (gsi);
+ if (!gimple_debug_source_bind_p (gstmt))
+ break;
+ if (gimple_debug_source_bind_get_value (gstmt) == var)
+ {
+ def = gimple_debug_source_bind_get_var (gstmt);
+ if (TREE_CODE (def) == DEBUG_EXPR_DECL)
+ break;
+ else
+ def = NULL_TREE;
+ }
+ }
+ /* If not, add a new source bind stmt. */
+ if (def == NULL_TREE)
+ {
+ gimple def_temp;
+ def = make_node (DEBUG_EXPR_DECL);
+ def_temp = gimple_build_debug_source_bind (def, var, NULL);
+ DECL_ARTIFICIAL (def) = 1;
+ TREE_TYPE (def) = TREE_TYPE (var);
+ DECL_MODE (def) = DECL_MODE (var);
+ gsi = gsi_after_labels (single_succ (ENTRY_BLOCK_PTR));
+ gsi_insert_before (&gsi, def_temp, GSI_SAME_STMT);
+ }
+ update = true;
+ }
+ }
+ else
+ {
+ def = get_current_def (var);
+ /* Check if get_current_def can be trusted. */
+ if (def)
+ {
+ basic_block bb = gimple_bb (stmt);
+ basic_block def_bb
+ = SSA_NAME_IS_DEFAULT_DEF (def)
+ ? NULL : gimple_bb (SSA_NAME_DEF_STMT (def));
+
+ /* If definition is in current bb, it is fine. */
+ if (bb == def_bb)
+ ;
+ /* If definition bb doesn't dominate the current bb,
+ it can't be used. */
+ else if (def_bb && !dominated_by_p (CDI_DOMINATORS, bb, def_bb))
+ def = NULL;
+ /* If there is just one definition and dominates the current
+ bb, it is fine. */
+ else if (get_phi_state (var) == NEED_PHI_STATE_NO)
+ ;
+ else
+ {
+ struct def_blocks_d *db_p = get_def_blocks_for (var);
+
+ /* If there are some non-debug uses in the current bb,
+ it is fine. */
+ if (bitmap_bit_p (db_p->livein_blocks, bb->index))
+ ;
+ /* Otherwise give up for now. */
+ else
+ def = NULL;
+ }
+ }
+ }
+ if (def == NULL)
+ {
+ gimple_debug_bind_reset_value (stmt);
+ update_stmt (stmt);
+ return;
+ }
+ SET_USE (use_p, def);
+ }
+ if (update)
+ update_stmt (stmt);
+}
+
/* SSA Rewriting Step 2. Rewrite every variable used in each statement in
the block with its immediate reaching definitions. Update the current
definition of a variable when a new real or virtual definition is found. */
static void
-rewrite_stmt (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb ATTRIBUTE_UNUSED,
- block_stmt_iterator si)
+rewrite_stmt (gimple_stmt_iterator si)
{
- tree stmt;
use_operand_p use_p;
def_operand_p def_p;
ssa_op_iter iter;
-
- stmt = bsi_stmt (si);
+ gimple stmt = gsi_stmt (si);
/* If mark_def_sites decided that we don't need to rewrite this
statement, ignore it. */
gcc_assert (blocks_to_update == NULL);
- if (!REWRITE_THIS_STMT (stmt) && !REGISTER_DEFS_IN_THIS_STMT (stmt))
+ if (!rewrite_uses_p (stmt) && !register_defs_p (stmt))
return;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "Renaming statement ");
- print_generic_stmt (dump_file, stmt, TDF_SLIM);
+ print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
fprintf (dump_file, "\n");
}
- /* Step 1. Rewrite USES and VUSES in the statement. */
- if (REWRITE_THIS_STMT (stmt))
- FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter,
- SSA_OP_ALL_USES|SSA_OP_ALL_KILLS)
- {
- tree var = USE_FROM_PTR (use_p);
- gcc_assert (DECL_P (var));
- SET_USE (use_p, get_reaching_def (var));
- }
+ /* Step 1. Rewrite USES in the statement. */
+ if (rewrite_uses_p (stmt))
+ {
+ if (is_gimple_debug (stmt))
+ rewrite_debug_stmt_uses (stmt);
+ else
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
+ {
+ tree var = USE_FROM_PTR (use_p);
+ gcc_assert (DECL_P (var));
+ SET_USE (use_p, get_reaching_def (var));
+ }
+ }
- /* Step 2. Register the statement's DEF and VDEF operands. */
- if (REGISTER_DEFS_IN_THIS_STMT (stmt))
- FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_ALL_DEFS)
+ /* Step 2. Register the statement's DEF operands. */
+ if (register_defs_p (stmt))
+ FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_DEF)
{
tree var = DEF_FROM_PTR (def_p);
+ tree name = make_ssa_name (var, stmt);
+ tree tracked_var;
gcc_assert (DECL_P (var));
- SET_DEF (def_p, make_ssa_name (var, stmt));
- register_new_def (DEF_FROM_PTR (def_p), &block_defs_stack);
+ SET_DEF (def_p, name);
+ register_new_def (DEF_FROM_PTR (def_p), var);
+
+ tracked_var = target_for_debug_bind (var);
+ if (tracked_var)
+ {
+ gimple note = gimple_build_debug_bind (tracked_var, name, stmt);
+ gsi_insert_after (&si, note, GSI_SAME_STMT);
+ }
}
}
that definition is reaching the PHI node. */
static void
-rewrite_add_phi_arguments (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb)
+rewrite_add_phi_arguments (basic_block bb)
{
edge e;
edge_iterator ei;
FOR_EACH_EDGE (e, ei, bb->succs)
{
- tree phi;
+ gimple phi;
+ gimple_stmt_iterator gsi;
- for (phi = phi_nodes (e->dest); phi; phi = PHI_CHAIN (phi))
+ for (gsi = gsi_start_phis (e->dest); !gsi_end_p (gsi);
+ gsi_next (&gsi))
{
tree currdef;
- currdef = get_reaching_def (SSA_NAME_VAR (PHI_RESULT (phi)));
- add_phi_arg (phi, currdef, e);
+ gimple stmt;
+
+ phi = gsi_stmt (gsi);
+ currdef = get_reaching_def (SSA_NAME_VAR (gimple_phi_result (phi)));
+ stmt = SSA_NAME_DEF_STMT (currdef);
+ add_phi_arg (phi, currdef, e, gimple_location (stmt));
}
}
}
+/* SSA Rewriting Step 1. Initialization, create a block local stack
+ of reaching definitions for new SSA names produced in this block
+ (BLOCK_DEFS). Register new definitions for every PHI node in the
+ block. */
+
+static void
+rewrite_enter_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
+ basic_block bb)
+{
+ gimple phi;
+ gimple_stmt_iterator gsi;
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "\n\nRenaming block #%d\n\n", bb->index);
+
+ /* Mark the unwind point for this block. */
+ VEC_safe_push (tree, heap, block_defs_stack, NULL_TREE);
+
+ /* Step 1. Register new definitions for every PHI node in the block.
+ Conceptually, all the PHI nodes are executed in parallel and each PHI
+ node introduces a new version for the associated variable. */
+ for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ tree result;
+
+ phi = gsi_stmt (gsi);
+ result = gimple_phi_result (phi);
+ gcc_assert (is_gimple_reg (result));
+ register_new_def (result, SSA_NAME_VAR (result));
+ }
+
+ /* Step 2. Rewrite every variable used in each statement in the block
+ with its immediate reaching definitions. Update the current definition
+ of a variable when a new real or virtual definition is found. */
+ if (TEST_BIT (interesting_blocks, bb->index))
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ rewrite_stmt (gsi);
+
+ /* Step 3. Visit all the successor blocks of BB looking for PHI nodes.
+ For every PHI node found, add a new argument containing the current
+ reaching definition for the variable and the edge through which that
+ definition is reaching the PHI node. */
+ rewrite_add_phi_arguments (bb);
+}
+
-/* Called after visiting basic block BB. Restore CURRDEFS to its
- original value. */
+
+/* Called after visiting all the statements in basic block BB and all
+ of its dominator children. Restore CURRDEFS to its original value. */
static void
-rewrite_finalize_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb ATTRIBUTE_UNUSED)
+rewrite_leave_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
+ basic_block bb ATTRIBUTE_UNUSED)
{
/* Restore CURRDEFS to its original state. */
while (VEC_length (tree, block_defs_stack) > 0)
if (tmp == NULL_TREE)
break;
- /* If we recorded an SSA_NAME, then make the SSA_NAME the current
- definition of its underlying variable. If we recorded anything
- else, it must have been an _DECL node and its current reaching
- definition must have been NULL. */
if (TREE_CODE (tmp) == SSA_NAME)
{
+ /* If we recorded an SSA_NAME, then make the SSA_NAME the
+ current definition of its underlying variable. Note that
+ if the SSA_NAME is not for a GIMPLE register, the symbol
+ being defined is stored in the next slot in the stack.
+ This mechanism is needed because an SSA name for a
+ non-register symbol may be the definition for more than
+ one symbol (e.g., SFTs, aliased variables, etc). */
saved_def = tmp;
var = SSA_NAME_VAR (saved_def);
+ if (!is_gimple_reg (var))
+ var = VEC_pop (tree, block_defs_stack);
}
else
{
+ /* If we recorded anything else, it must have been a _DECL
+ node and its current reaching definition must have been
+ NULL. */
saved_def = NULL;
var = tmp;
}
-
+
set_current_def (var, saved_def);
}
}
+/* Dump bitmap SET (assumed to contain VAR_DECLs) to FILE. */
+
+void
+dump_decl_set (FILE *file, bitmap set)
+{
+ if (set)
+ {
+ bitmap_iterator bi;
+ unsigned i;
+
+ fprintf (file, "{ ");
+
+ EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi)
+ {
+ tree var = referenced_var_lookup (cfun, i);
+ if (var)
+ print_generic_expr (file, var, 0);
+ else
+ fprintf (file, "D.%u", i);
+ fprintf (file, " ");
+ }
+
+ fprintf (file, "}");
+ }
+ else
+ fprintf (file, "NIL");
+}
+
+
+/* Dump bitmap SET (assumed to contain VAR_DECLs) to FILE. */
+
+DEBUG_FUNCTION void
+debug_decl_set (bitmap set)
+{
+ dump_decl_set (stderr, set);
+ fprintf (stderr, "\n");
+}
+
+
+/* Dump the renaming stack (block_defs_stack) to FILE. Traverse the
+ stack up to a maximum of N levels. If N is -1, the whole stack is
+ dumped. New levels are created when the dominator tree traversal
+ used for renaming enters a new sub-tree. */
+
+void
+dump_defs_stack (FILE *file, int n)
+{
+ int i, j;
+
+ fprintf (file, "\n\nRenaming stack");
+ if (n > 0)
+ fprintf (file, " (up to %d levels)", n);
+ fprintf (file, "\n\n");
+
+ i = 1;
+ fprintf (file, "Level %d (current level)\n", i);
+ for (j = (int) VEC_length (tree, block_defs_stack) - 1; j >= 0; j--)
+ {
+ tree name, var;
+
+ name = VEC_index (tree, block_defs_stack, j);
+ if (name == NULL_TREE)
+ {
+ i++;
+ if (n > 0 && i > n)
+ break;
+ fprintf (file, "\nLevel %d\n", i);
+ continue;
+ }
+
+ if (DECL_P (name))
+ {
+ var = name;
+ name = NULL_TREE;
+ }
+ else
+ {
+ var = SSA_NAME_VAR (name);
+ if (!is_gimple_reg (var))
+ {
+ j--;
+ var = VEC_index (tree, block_defs_stack, j);
+ }
+ }
+
+ fprintf (file, " Previous CURRDEF (");
+ print_generic_expr (file, var, 0);
+ fprintf (file, ") = ");
+ if (name)
+ print_generic_expr (file, name, 0);
+ else
+ fprintf (file, "<NIL>");
+ fprintf (file, "\n");
+ }
+}
+
+
+/* Dump the renaming stack (block_defs_stack) to stderr. Traverse the
+ stack up to a maximum of N levels. If N is -1, the whole stack is
+ dumped. New levels are created when the dominator tree traversal
+ used for renaming enters a new sub-tree. */
+
+DEBUG_FUNCTION void
+debug_defs_stack (int n)
+{
+ dump_defs_stack (stderr, n);
+}
+
+
+/* Dump the current reaching definition of every symbol to FILE. */
+
+void
+dump_currdefs (FILE *file)
+{
+ referenced_var_iterator i;
+ tree var;
+
+ fprintf (file, "\n\nCurrent reaching definitions\n\n");
+ FOR_EACH_REFERENCED_VAR (cfun, var, i)
+ if (SYMS_TO_RENAME (cfun) == NULL
+ || bitmap_bit_p (SYMS_TO_RENAME (cfun), DECL_UID (var)))
+ {
+ fprintf (file, "CURRDEF (");
+ print_generic_expr (file, var, 0);
+ fprintf (file, ") = ");
+ if (get_current_def (var))
+ print_generic_expr (file, get_current_def (var), 0);
+ else
+ fprintf (file, "<NIL>");
+ fprintf (file, "\n");
+ }
+}
+
+
+/* Dump the current reaching definition of every symbol to stderr. */
+
+DEBUG_FUNCTION void
+debug_currdefs (void)
+{
+ dump_currdefs (stderr);
+}
+
+
/* Dump SSA information to FILE. */
void
dump_tree_ssa (FILE *file)
{
- basic_block bb;
const char *funcname
= lang_hooks.decl_printable_name (current_function_decl, 2);
- fprintf (file, "SSA information for %s\n\n", funcname);
+ fprintf (file, "SSA renaming information for %s\n\n", funcname);
- FOR_EACH_BB (bb)
- {
- dump_bb (bb, file, 0);
- fputs (" ", file);
- print_generic_stmt (file, phi_nodes (bb), dump_flags);
- fputs ("\n\n", file);
- }
+ dump_def_blocks (file);
+ dump_defs_stack (file, -1);
+ dump_currdefs (file);
+ dump_tree_ssa_stats (file);
}
/* Dump SSA information to stderr. */
-void
+DEBUG_FUNCTION void
debug_tree_ssa (void)
{
dump_tree_ssa (stderr);
void
dump_tree_ssa_stats (FILE *file)
{
- fprintf (file, "\nHash table statistics:\n");
+ if (def_blocks || repl_tbl)
+ fprintf (file, "\nHash table statistics:\n");
- fprintf (file, " def_blocks: ");
- htab_statistics (file, def_blocks);
+ if (def_blocks)
+ {
+ fprintf (file, " def_blocks: ");
+ htab_statistics (file, def_blocks);
+ }
+
+ if (repl_tbl)
+ {
+ fprintf (file, " repl_tbl: ");
+ htab_statistics (file, repl_tbl);
+ }
- fprintf (file, "\n");
+ if (def_blocks || repl_tbl)
+ fprintf (file, "\n");
}
/* Dump SSA statistics on stderr. */
-void
+DEBUG_FUNCTION void
debug_tree_ssa_stats (void)
{
dump_tree_ssa_stats (stderr);
/* Callback for htab_traverse to dump the DEF_BLOCKS hash table. */
static int
-debug_def_blocks_r (void **slot, void *data ATTRIBUTE_UNUSED)
+debug_def_blocks_r (void **slot, void *data)
{
+ FILE *file = (FILE *) data;
struct def_blocks_d *db_p = (struct def_blocks_d *) *slot;
-
- fprintf (stderr, "VAR: ");
- print_generic_expr (stderr, db_p->var, dump_flags);
- bitmap_print (stderr, db_p->def_blocks, ", DEF_BLOCKS: { ", "}");
- bitmap_print (stderr, db_p->livein_blocks, ", LIVEIN_BLOCKS: { ", "}\n");
+
+ fprintf (file, "VAR: ");
+ print_generic_expr (file, db_p->var, dump_flags);
+ bitmap_print (file, db_p->def_blocks, ", DEF_BLOCKS: { ", "}");
+ bitmap_print (file, db_p->livein_blocks, ", LIVEIN_BLOCKS: { ", "}");
+ bitmap_print (file, db_p->phi_blocks, ", PHI_BLOCKS: { ", "}\n");
return 1;
}
-/* Dump the DEF_BLOCKS hash table on stderr. */
+/* Dump the DEF_BLOCKS hash table on FILE. */
void
+dump_def_blocks (FILE *file)
+{
+ fprintf (file, "\n\nDefinition and live-in blocks:\n\n");
+ if (def_blocks)
+ htab_traverse (def_blocks, debug_def_blocks_r, file);
+}
+
+
+/* Dump the DEF_BLOCKS hash table on stderr. */
+
+DEBUG_FUNCTION void
debug_def_blocks (void)
{
- htab_traverse (def_blocks, debug_def_blocks_r, NULL);
+ dump_def_blocks (stderr);
}
{
tree currdef = get_current_def (old_name);
- /* Push the current reaching definition into *BLOCK_DEFS_P.
+ /* Push the current reaching definition into BLOCK_DEFS_STACK.
This stack is later used by the dominator tree callbacks to
restore the reaching definitions for all the variables
defined in the block after a recursive visit to all its
}
-/* Initialization of block data structures for the incremental SSA
- update pass. Create a block local stack of reaching definitions
- for new SSA names produced in this block (BLOCK_DEFS). Register
- new definitions for every PHI node in the block. */
-
-static void
-rewrite_update_init_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb)
-{
- edge e;
- edge_iterator ei;
- tree phi;
- bool is_abnormal_phi;
-
- if (dump_file && (dump_flags & TDF_DETAILS))
- fprintf (dump_file, "\n\nRegistering new PHI nodes in block #%d\n\n",
- bb->index);
-
- /* Mark the unwind point for this block. */
- VEC_safe_push (tree, heap, block_defs_stack, NULL_TREE);
-
- if (!bitmap_bit_p (blocks_to_update, bb->index))
- return;
-
- /* Mark the LHS if any of the arguments flows through an abnormal
- edge. */
- is_abnormal_phi = false;
- FOR_EACH_EDGE (e, ei, bb->preds)
- if (e->flags & EDGE_ABNORMAL)
- {
- is_abnormal_phi = true;
- break;
- }
-
- /* If any of the PHI nodes is a replacement for a name in
- OLD_SSA_NAMES or it's one of the names in NEW_SSA_NAMES, then
- register it as a new definition for its corresponding name. Also
- register definitions for names whose underlying symbols are
- marked for renaming. */
-
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
- {
- tree lhs, lhs_sym;
-
- if (!REGISTER_DEFS_IN_THIS_STMT (phi))
- continue;
-
- lhs = PHI_RESULT (phi);
- lhs_sym = SSA_NAME_VAR (lhs);
-
- if (symbol_marked_for_renaming (lhs_sym))
- register_new_update_single (lhs, lhs_sym);
- else
- {
- /* If LHS is a new name, register a new definition for all
- the names replaced by LHS. */
- if (is_new_name (lhs))
- register_new_update_set (lhs, names_replaced_by (lhs));
-
- /* If LHS is an OLD name, register it as a new definition
- for itself. */
- if (is_old_name (lhs))
- register_new_update_single (lhs, lhs);
- }
-
- if (is_abnormal_phi)
- SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs) = 1;
- }
-}
-
-
-/* Called after visiting block BB. Unwind BLOCK_DEFS_STACK to restore
- the current reaching definition of every name re-written in BB to
- the original reaching definition before visiting BB. This
- unwinding must be done in the opposite order to what is done in
- register_new_update_set. */
-
-static void
-rewrite_update_fini_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb ATTRIBUTE_UNUSED)
-{
- while (VEC_length (tree, block_defs_stack) > 0)
- {
- tree var = VEC_pop (tree, block_defs_stack);
- tree saved_def;
-
- /* NULL indicates the unwind stop point for this block (see
- rewrite_update_init_block). */
- if (var == NULL)
- return;
-
- saved_def = VEC_pop (tree, block_defs_stack);
- set_current_def (var, saved_def);
- }
-}
-
/* If the operand pointed to by USE_P is a name in OLD_SSA_NAMES or
it is a symbol marked for renaming, replace it with USE_P's current
}
+/* Same as maybe_replace_use, but without introducing default stmts,
+ returning false to indicate a need to do so. */
+
+static inline bool
+maybe_replace_use_in_debug_stmt (use_operand_p use_p)
+{
+ tree rdef = NULL_TREE;
+ tree use = USE_FROM_PTR (use_p);
+ tree sym = DECL_P (use) ? use : SSA_NAME_VAR (use);
+
+ if (symbol_marked_for_renaming (sym))
+ rdef = get_current_def (sym);
+ else if (is_old_name (use))
+ {
+ rdef = get_current_def (use);
+ /* We can't assume that, if there's no current definition, the
+ default one should be used. It could be the case that we've
+ rearranged blocks so that the earlier definition no longer
+ dominates the use. */
+ if (!rdef && SSA_NAME_IS_DEFAULT_DEF (use))
+ rdef = use;
+ }
+ else
+ rdef = use;
+
+ if (rdef && rdef != use)
+ SET_USE (use_p, rdef);
+
+ return rdef != NULL_TREE;
+}
+
+
/* If the operand pointed to by DEF_P is an SSA name in NEW_SSA_NAMES
or OLD_SSA_NAMES, or if it is a symbol marked for renaming,
register it as the current definition for the names replaced by
DEF_P. */
static inline void
-maybe_register_def (def_operand_p def_p, tree stmt)
+maybe_register_def (def_operand_p def_p, gimple stmt,
+ gimple_stmt_iterator gsi)
{
tree def = DEF_FROM_PTR (def_p);
tree sym = DECL_P (def) ? def : SSA_NAME_VAR (def);
- /* If DEF is a naked symbol that needs renaming, create a
- new name for it. */
+ /* If DEF is a naked symbol that needs renaming, create a new
+ name for it. */
if (symbol_marked_for_renaming (sym))
{
if (DECL_P (def))
{
+ tree tracked_var;
+
def = make_ssa_name (def, stmt);
SET_DEF (def_p, def);
+
+ tracked_var = target_for_debug_bind (sym);
+ if (tracked_var)
+ {
+ gimple note = gimple_build_debug_bind (tracked_var, def, stmt);
+ /* If stmt ends the bb, insert the debug stmt on the single
+ non-EH edge from the stmt. */
+ if (gsi_one_before_end_p (gsi) && stmt_ends_bb_p (stmt))
+ {
+ basic_block bb = gsi_bb (gsi);
+ edge_iterator ei;
+ edge e, ef = NULL;
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ if (!(e->flags & EDGE_EH))
+ {
+ gcc_assert (!ef);
+ ef = e;
+ }
+ /* If there are other predecessors to ef->dest, then
+ there must be PHI nodes for the modified
+ variable, and therefore there will be debug bind
+ stmts after the PHI nodes. The debug bind notes
+ we'd insert would force the creation of a new
+ block (diverging codegen) and be redundant with
+ the post-PHI bind stmts, so don't add them.
+
+ As for the exit edge, there wouldn't be redundant
+ bind stmts, but there wouldn't be a PC to bind
+ them to either, so avoid diverging the CFG. */
+ if (ef && single_pred_p (ef->dest)
+ && ef->dest != EXIT_BLOCK_PTR)
+ {
+ /* If there were PHI nodes in the node, we'd
+ have to make sure the value we're binding
+ doesn't need rewriting. But there shouldn't
+ be PHI nodes in a single-predecessor block,
+ so we just add the note. */
+ gsi_insert_on_edge_immediate (ef, note);
+ }
+ }
+ else
+ gsi_insert_after (&gsi, note, GSI_SAME_STMT);
+ }
}
register_new_update_single (def, sym);
in OLD_SSA_NAMES. */
static void
-rewrite_update_stmt (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb ATTRIBUTE_UNUSED,
- block_stmt_iterator si)
+rewrite_update_stmt (gimple stmt, gimple_stmt_iterator gsi)
{
- stmt_ann_t ann;
- tree stmt;
use_operand_p use_p;
def_operand_p def_p;
ssa_op_iter iter;
- stmt = bsi_stmt (si);
- ann = stmt_ann (stmt);
-
- gcc_assert (bitmap_bit_p (blocks_to_update, bb->index));
-
/* Only update marked statements. */
- if (!REWRITE_THIS_STMT (stmt) && !REGISTER_DEFS_IN_THIS_STMT (stmt))
+ if (!rewrite_uses_p (stmt) && !register_defs_p (stmt))
return;
if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "Updating SSA information for statement ");
- print_generic_stmt (dump_file, stmt, TDF_SLIM);
- fprintf (dump_file, "\n");
+ print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
}
/* Rewrite USES included in OLD_SSA_NAMES and USES whose underlying
symbol is marked for renaming. */
- if (REWRITE_THIS_STMT (stmt))
+ if (rewrite_uses_p (stmt))
{
- FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
- maybe_replace_use (use_p);
+ if (is_gimple_debug (stmt))
+ {
+ bool failed = false;
- if (need_to_update_vops_p)
- FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter,
- SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
- maybe_replace_use (use_p);
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
+ if (!maybe_replace_use_in_debug_stmt (use_p))
+ {
+ failed = true;
+ break;
+ }
+
+ if (failed)
+ {
+ /* DOM sometimes threads jumps in such a way that a
+ debug stmt ends up referencing a SSA variable that no
+ longer dominates the debug stmt, but such that all
+ incoming definitions refer to the same definition in
+ an earlier dominator. We could try to recover that
+ definition somehow, but this will have to do for now.
+
+ Introducing a default definition, which is what
+ maybe_replace_use() would do in such cases, may
+ modify code generation, for the otherwise-unused
+ default definition would never go away, modifying SSA
+ version numbers all over. */
+ gimple_debug_bind_reset_value (stmt);
+ update_stmt (stmt);
+ }
+ }
+ else
+ {
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_ALL_USES)
+ maybe_replace_use (use_p);
+ }
}
/* Register definitions of names in NEW_SSA_NAMES and OLD_SSA_NAMES.
Also register definitions for names whose underlying symbol is
marked for renaming. */
- if (REGISTER_DEFS_IN_THIS_STMT (stmt))
- {
- FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_DEF)
- maybe_register_def (def_p, stmt);
-
- if (need_to_update_vops_p)
- FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_VIRTUAL_DEFS)
- maybe_register_def (def_p, stmt);
- }
-}
-
-
-/* Replace the operand pointed to by USE_P with USE's current reaching
- definition. */
-
-static inline void
-replace_use (use_operand_p use_p, tree use)
-{
- tree rdef = get_reaching_def (use);
- if (rdef != use)
- SET_USE (use_p, rdef);
+ if (register_defs_p (stmt))
+ FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, iter, SSA_OP_ALL_DEFS)
+ maybe_register_def (def_p, stmt, gsi);
}
definition, replace it. */
static void
-rewrite_update_phi_arguments (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
- basic_block bb)
+rewrite_update_phi_arguments (basic_block bb)
{
edge e;
edge_iterator ei;
FOR_EACH_EDGE (e, ei, bb->succs)
{
- tree phi;
- tree_vec phis;
+ gimple phi;
+ gimple_vec phis;
if (!bitmap_bit_p (blocks_with_phis_to_rewrite, e->dest->index))
continue;
-
- phis = VEC_index (tree_vec, phis_to_rewrite, e->dest->index);
- for (i = 0; VEC_iterate (tree, phis, i, phi); i++)
+
+ phis = VEC_index (gimple_vec, phis_to_rewrite, e->dest->index);
+ FOR_EACH_VEC_ELT (gimple, phis, i, phi)
{
- tree arg;
+ tree arg, lhs_sym, reaching_def = NULL;
use_operand_p arg_p;
- gcc_assert (REWRITE_THIS_STMT (phi));
+ gcc_assert (rewrite_uses_p (phi));
arg_p = PHI_ARG_DEF_PTR_FROM_EDGE (phi, e);
arg = USE_FROM_PTR (arg_p);
if (arg && !DECL_P (arg) && TREE_CODE (arg) != SSA_NAME)
continue;
+ lhs_sym = SSA_NAME_VAR (gimple_phi_result (phi));
+
if (arg == NULL_TREE)
{
/* When updating a PHI node for a recently introduced
symbol we may find NULL arguments. That's why we
take the symbol from the LHS of the PHI node. */
- replace_use (arg_p, SSA_NAME_VAR (PHI_RESULT (phi)));
+ reaching_def = get_reaching_def (lhs_sym);
+
}
else
{
tree sym = DECL_P (arg) ? arg : SSA_NAME_VAR (arg);
if (symbol_marked_for_renaming (sym))
- replace_use (arg_p, sym);
+ reaching_def = get_reaching_def (sym);
else if (is_old_name (arg))
- replace_use (arg_p, arg);
+ reaching_def = get_reaching_def (arg);
+ }
+
+ /* Update the argument if there is a reaching def. */
+ if (reaching_def)
+ {
+ gimple stmt;
+ source_location locus;
+ int arg_i = PHI_ARG_INDEX_FROM_USE (arg_p);
+
+ SET_USE (arg_p, reaching_def);
+ stmt = SSA_NAME_DEF_STMT (reaching_def);
+
+ /* Single element PHI nodes behave like copies, so get the
+ location from the phi argument. */
+ if (gimple_code (stmt) == GIMPLE_PHI &&
+ gimple_phi_num_args (stmt) == 1)
+ locus = gimple_phi_arg_location (stmt, 0);
+ else
+ locus = gimple_location (stmt);
+
+ gimple_phi_arg_set_location (phi, arg_i, locus);
}
+
if (e->flags & EDGE_ABNORMAL)
SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (arg_p)) = 1;
}
}
+/* Initialization of block data structures for the incremental SSA
+ update pass. Create a block local stack of reaching definitions
+ for new SSA names produced in this block (BLOCK_DEFS). Register
+ new definitions for every PHI node in the block. */
+
+static void
+rewrite_update_enter_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
+ basic_block bb)
+{
+ bool is_abnormal_phi;
+ gimple_stmt_iterator gsi;
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "Registering new PHI nodes in block #%d\n",
+ bb->index);
+
+ /* Mark the unwind point for this block. */
+ VEC_safe_push (tree, heap, block_defs_stack, NULL_TREE);
+
+ if (!bitmap_bit_p (blocks_to_update, bb->index))
+ return;
+
+ /* Mark the LHS if any of the arguments flows through an abnormal
+ edge. */
+ is_abnormal_phi = bb_has_abnormal_pred (bb);
+
+ /* If any of the PHI nodes is a replacement for a name in
+ OLD_SSA_NAMES or it's one of the names in NEW_SSA_NAMES, then
+ register it as a new definition for its corresponding name. Also
+ register definitions for names whose underlying symbols are
+ marked for renaming. */
+ for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ tree lhs, lhs_sym;
+ gimple phi = gsi_stmt (gsi);
+
+ if (!register_defs_p (phi))
+ continue;
+
+ lhs = gimple_phi_result (phi);
+ lhs_sym = SSA_NAME_VAR (lhs);
+
+ if (symbol_marked_for_renaming (lhs_sym))
+ register_new_update_single (lhs, lhs_sym);
+ else
+ {
+
+ /* If LHS is a new name, register a new definition for all
+ the names replaced by LHS. */
+ if (is_new_name (lhs))
+ register_new_update_set (lhs, names_replaced_by (lhs));
+
+ /* If LHS is an OLD name, register it as a new definition
+ for itself. */
+ if (is_old_name (lhs))
+ register_new_update_single (lhs, lhs);
+ }
+
+ if (is_abnormal_phi)
+ SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs) = 1;
+ }
+
+ /* Step 2. Rewrite every variable used in each statement in the block. */
+ if (TEST_BIT (interesting_blocks, bb->index))
+ {
+ gcc_assert (bitmap_bit_p (blocks_to_update, bb->index));
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ rewrite_update_stmt (gsi_stmt (gsi), gsi);
+ }
+
+ /* Step 3. Update PHI nodes. */
+ rewrite_update_phi_arguments (bb);
+}
+
+/* Called after visiting block BB. Unwind BLOCK_DEFS_STACK to restore
+ the current reaching definition of every name re-written in BB to
+ the original reaching definition before visiting BB. This
+ unwinding must be done in the opposite order to what is done in
+ register_new_update_set. */
+
+static void
+rewrite_update_leave_block (struct dom_walk_data *walk_data ATTRIBUTE_UNUSED,
+ basic_block bb ATTRIBUTE_UNUSED)
+{
+ while (VEC_length (tree, block_defs_stack) > 0)
+ {
+ tree var = VEC_pop (tree, block_defs_stack);
+ tree saved_def;
+
+ /* NULL indicates the unwind stop point for this block (see
+ rewrite_update_enter_block). */
+ if (var == NULL)
+ return;
+
+ saved_def = VEC_pop (tree, block_defs_stack);
+ set_current_def (var, saved_def);
+ }
+}
+
+
/* Rewrite the actual blocks, statements, and PHI arguments, to be in SSA
- form.
+ form.
ENTRY indicates the block where to start. Every block dominated by
ENTRY will be rewritten.
are not present in BLOCKS are ignored. */
static void
-rewrite_blocks (basic_block entry, enum rewrite_mode what, sbitmap blocks)
+rewrite_blocks (basic_block entry, enum rewrite_mode what)
{
struct dom_walk_data walk_data;
-
+
/* Rewrite all the basic blocks in the program. */
timevar_push (TV_TREE_SSA_REWRITE_BLOCKS);
memset (&walk_data, 0, sizeof (walk_data));
walk_data.dom_direction = CDI_DOMINATORS;
- walk_data.interesting_blocks = blocks;
-
- if (what == REWRITE_UPDATE)
- walk_data.before_dom_children_before_stmts = rewrite_update_init_block;
- else
- walk_data.before_dom_children_before_stmts = rewrite_initialize_block;
-
- if (what == REWRITE_ALL)
- walk_data.before_dom_children_walk_stmts = rewrite_stmt;
- else if (what == REWRITE_UPDATE)
- walk_data.before_dom_children_walk_stmts = rewrite_update_stmt;
- else
- gcc_unreachable ();
if (what == REWRITE_ALL)
- walk_data.before_dom_children_after_stmts = rewrite_add_phi_arguments;
- else if (what == REWRITE_UPDATE)
- walk_data.before_dom_children_after_stmts = rewrite_update_phi_arguments;
- else
- gcc_unreachable ();
-
- if (what == REWRITE_ALL)
- walk_data.after_dom_children_after_stmts = rewrite_finalize_block;
+ {
+ walk_data.before_dom_children = rewrite_enter_block;
+ walk_data.after_dom_children = rewrite_leave_block;
+ }
else if (what == REWRITE_UPDATE)
- walk_data.after_dom_children_after_stmts = rewrite_update_fini_block;
+ {
+ walk_data.before_dom_children = rewrite_update_enter_block;
+ walk_data.after_dom_children = rewrite_update_leave_block;
+ }
else
gcc_unreachable ();
dump_tree_ssa_stats (dump_file);
}
- if (def_blocks)
- {
- htab_delete (def_blocks);
- def_blocks = NULL;
- }
-
VEC_free (tree, heap, block_defs_stack);
timevar_pop (TV_TREE_SSA_REWRITE_BLOCKS);
}
-/* Block initialization routine for mark_def_sites. Clear the
- KILLS bitmap at the start of each block. */
+/* Block processing routine for mark_def_sites. Clear the KILLS bitmap
+ at the start of each block, and call mark_def_sites for each statement. */
static void
-mark_def_sites_initialize_block (struct dom_walk_data *walk_data,
- basic_block bb ATTRIBUTE_UNUSED)
+mark_def_sites_block (struct dom_walk_data *walk_data, basic_block bb)
{
- struct mark_def_sites_global_data *gd =
- (struct mark_def_sites_global_data *) walk_data->global_data;
- bitmap kills = gd->kills;
+ struct mark_def_sites_global_data *gd;
+ bitmap kills;
+ gimple_stmt_iterator gsi;
+
+ gd = (struct mark_def_sites_global_data *) walk_data->global_data;
+ kills = gd->kills;
+
bitmap_clear (kills);
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ mark_def_sites (bb, gsi_stmt (gsi), kills);
}
/* Mark the definition site blocks for each variable, so that we know
where the variable is actually live.
- INTERESTING_BLOCKS will be filled in with all the blocks that
- should be processed by the renamer. It is assumed to be
- initialized and zeroed by the caller. */
+ The INTERESTING_BLOCKS global will be filled in with all the blocks
+ that should be processed by the renamer. It is assumed that the
+ caller has already initialized and zeroed it. */
static void
-mark_def_site_blocks (sbitmap interesting_blocks)
+mark_def_site_blocks (void)
{
struct dom_walk_data walk_data;
struct mark_def_sites_global_data mark_def_sites_global_data;
- referenced_var_iterator rvi;
- tree var;
-
- /* Allocate memory for the DEF_BLOCKS hash table. */
- def_blocks = htab_create (num_referenced_vars,
- def_blocks_hash, def_blocks_eq, def_blocks_free);
- FOR_EACH_REFERENCED_VAR(var, rvi)
- set_current_def (var, NULL_TREE);
/* Setup callbacks for the generic dominator tree walker to find and
mark definition sites. */
- walk_data.walk_stmts_backward = false;
walk_data.dom_direction = CDI_DOMINATORS;
walk_data.initialize_block_local_data = NULL;
- walk_data.before_dom_children_before_stmts = mark_def_sites_initialize_block;
- walk_data.before_dom_children_walk_stmts = mark_def_sites;
- walk_data.before_dom_children_after_stmts = NULL;
- walk_data.after_dom_children_before_stmts = NULL;
- walk_data.after_dom_children_walk_stmts = NULL;
- walk_data.after_dom_children_after_stmts = NULL;
- walk_data.interesting_blocks = NULL;
+ walk_data.before_dom_children = mark_def_sites_block;
+ walk_data.after_dom_children = NULL;
/* Notice that this bitmap is indexed using variable UIDs, so it must be
large enough to accommodate all the variables referenced in the
function, not just the ones we are renaming. */
mark_def_sites_global_data.kills = BITMAP_ALLOC (NULL);
-
- /* Create the set of interesting blocks that will be filled by
- mark_def_sites. */
- mark_def_sites_global_data.interesting_blocks = interesting_blocks;
walk_data.global_data = &mark_def_sites_global_data;
/* We do not have any local data. */
}
+/* Initialize internal data needed during renaming. */
+
+static void
+init_ssa_renamer (void)
+{
+ tree var;
+ referenced_var_iterator rvi;
+
+ cfun->gimple_df->in_ssa_p = false;
+
+ /* Allocate memory for the DEF_BLOCKS hash table. */
+ gcc_assert (def_blocks == NULL);
+ def_blocks = htab_create (num_referenced_vars, def_blocks_hash,
+ def_blocks_eq, def_blocks_free);
+
+ FOR_EACH_REFERENCED_VAR (cfun, var, rvi)
+ set_current_def (var, NULL_TREE);
+}
+
+
+/* Deallocate internal data structures used by the renamer. */
+
+static void
+fini_ssa_renamer (void)
+{
+ if (def_blocks)
+ {
+ htab_delete (def_blocks);
+ def_blocks = NULL;
+ }
+
+ cfun->gimple_df->in_ssa_p = true;
+}
+
/* Main entry point into the SSA builder. The renaming process
proceeds in four main phases:
static unsigned int
rewrite_into_ssa (void)
{
- bitmap *dfs;
+ bitmap_head *dfs;
basic_block bb;
- sbitmap interesting_blocks;
-
- timevar_push (TV_TREE_SSA_OTHER);
/* Initialize operand data structures. */
init_ssa_operands ();
+ /* Initialize internal data needed by the renamer. */
+ init_ssa_renamer ();
+
/* Initialize the set of interesting blocks. The callback
mark_def_sites will add to this set those blocks that the renamer
should process. */
sbitmap_zero (interesting_blocks);
/* Initialize dominance frontier. */
- dfs = (bitmap *) xmalloc (last_basic_block * sizeof (bitmap));
+ dfs = XNEWVEC (bitmap_head, last_basic_block);
FOR_EACH_BB (bb)
- dfs[bb->index] = BITMAP_ALLOC (NULL);
+ bitmap_initialize (&dfs[bb->index], &bitmap_default_obstack);
/* 1- Compute dominance frontiers. */
calculate_dominance_info (CDI_DOMINATORS);
compute_dominance_frontiers (dfs);
/* 2- Find and mark definition sites. */
- mark_def_site_blocks (interesting_blocks);
+ mark_def_site_blocks ();
/* 3- Insert PHI nodes at dominance frontiers of definition blocks. */
insert_phi_nodes (dfs);
/* 4- Rename all the blocks. */
- rewrite_blocks (ENTRY_BLOCK_PTR, REWRITE_ALL, interesting_blocks);
+ rewrite_blocks (ENTRY_BLOCK_PTR, REWRITE_ALL);
/* Free allocated memory. */
FOR_EACH_BB (bb)
- BITMAP_FREE (dfs[bb->index]);
+ bitmap_clear (&dfs[bb->index]);
free (dfs);
+
sbitmap_free (interesting_blocks);
- timevar_pop (TV_TREE_SSA_OTHER);
- in_ssa_p = true;
+ fini_ssa_renamer ();
+
return 0;
}
-struct tree_opt_pass pass_build_ssa =
+struct gimple_opt_pass pass_build_ssa =
{
+ {
+ GIMPLE_PASS,
"ssa", /* name */
NULL, /* gate */
rewrite_into_ssa, /* execute */
NULL, /* sub */
NULL, /* next */
0, /* static_pass_number */
- 0, /* tv_id */
+ TV_TREE_SSA_OTHER, /* tv_id */
PROP_cfg | PROP_referenced_vars, /* properties_required */
PROP_ssa, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_func
+ TODO_update_ssa_only_virtuals
| TODO_verify_ssa
- | TODO_remove_unused_locals, /* todo_flags_finish */
- 0 /* letter */
+ | TODO_remove_unused_locals /* todo_flags_finish */
+ }
};
renamer. BLOCKS is the set of blocks that need updating. */
static void
-mark_def_interesting (tree var, tree stmt, basic_block bb, bool insert_phi_p)
+mark_def_interesting (tree var, gimple stmt, basic_block bb, bool insert_phi_p)
{
gcc_assert (bitmap_bit_p (blocks_to_update, bb->index));
- REGISTER_DEFS_IN_THIS_STMT (stmt) = 1;
+ set_register_defs (stmt, true);
if (insert_phi_p)
{
- bool is_phi_p = TREE_CODE (stmt) == PHI_NODE;
+ bool is_phi_p = gimple_code (stmt) == GIMPLE_PHI;
set_def_block (var, bb, is_phi_p);
nodes. */
static inline void
-mark_use_interesting (tree var, tree stmt, basic_block bb, bool insert_phi_p)
+mark_use_interesting (tree var, gimple stmt, basic_block bb, bool insert_phi_p)
{
- basic_block def_bb = bb_for_stmt (stmt);
+ basic_block def_bb = gimple_bb (stmt);
mark_block_for_update (def_bb);
mark_block_for_update (bb);
- if (TREE_CODE (stmt) == PHI_NODE)
+ if (gimple_code (stmt) == GIMPLE_PHI)
mark_phi_for_rewrite (def_bb, stmt);
else
- REWRITE_THIS_STMT (stmt) = 1;
+ {
+ set_rewrite_uses (stmt, true);
+
+ if (is_gimple_debug (stmt))
+ return;
+ }
/* If VAR has not been defined in BB, then it is live-on-entry
to BB. Note that we cannot just use the block holding VAR's
If INSERT_PHI_P is true, mark those uses as live in the
corresponding block. This is later used by the PHI placement
- algorithm to make PHI pruning decisions. */
+ algorithm to make PHI pruning decisions.
+
+ FIXME. Most of this would be unnecessary if we could associate a
+ symbol to all the SSA names that reference it. But that
+ sounds like it would be expensive to maintain. Still, it
+ would be interesting to see if it makes better sense to do
+ that. */
static void
prepare_block_for_update (basic_block bb, bool insert_phi_p)
{
basic_block son;
- block_stmt_iterator si;
- tree phi;
+ gimple_stmt_iterator si;
edge e;
edge_iterator ei;
/* Process PHI nodes marking interesting those that define or use
the symbols that we are interested in. */
- for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+ for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si))
{
- tree lhs_sym, lhs = PHI_RESULT (phi);
+ gimple phi = gsi_stmt (si);
+ tree lhs_sym, lhs = gimple_phi_result (phi);
lhs_sym = DECL_P (lhs) ? lhs : SSA_NAME_VAR (lhs);
if (!symbol_marked_for_renaming (lhs_sym))
continue;
+
mark_def_interesting (lhs_sym, phi, bb, insert_phi_p);
/* Mark the uses in phi nodes as interesting. It would be more correct
block that also contains its definition, and thus insert a few more
phi nodes for it. */
FOR_EACH_EDGE (e, ei, bb->preds)
- {
- mark_use_interesting (lhs_sym, phi, e->src, insert_phi_p);
- }
+ mark_use_interesting (lhs_sym, phi, e->src, insert_phi_p);
}
/* Process the statements. */
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
+ for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
{
- tree stmt;
+ gimple stmt;
ssa_op_iter i;
use_operand_p use_p;
def_operand_p def_p;
-
- stmt = bsi_stmt (si);
- FOR_EACH_SSA_USE_OPERAND (use_p, stmt, i, SSA_OP_USE)
+ stmt = gsi_stmt (si);
+
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, i, SSA_OP_ALL_USES)
{
tree use = USE_FROM_PTR (use_p);
tree sym = DECL_P (use) ? use : SSA_NAME_VAR (use);
if (symbol_marked_for_renaming (sym))
- mark_use_interesting (use, stmt, bb, insert_phi_p);
- }
-
- FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, i, SSA_OP_DEF)
- {
- tree def = DEF_FROM_PTR (def_p);
- tree sym = DECL_P (def) ? def : SSA_NAME_VAR (def);
-
- if (symbol_marked_for_renaming (sym))
- mark_def_interesting (def, stmt, bb, insert_phi_p);
+ mark_use_interesting (sym, stmt, bb, insert_phi_p);
}
- FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, i, SSA_OP_VIRTUAL_DEFS)
+ FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, i, SSA_OP_ALL_DEFS)
{
tree def = DEF_FROM_PTR (def_p);
tree sym = DECL_P (def) ? def : SSA_NAME_VAR (def);
-
- if (symbol_marked_for_renaming (sym))
- {
- mark_use_interesting (sym, stmt, bb, insert_phi_p);
- mark_def_interesting (sym, stmt, bb, insert_phi_p);
- }
- }
-
- FOR_EACH_SSA_USE_OPERAND (use_p, stmt, i, SSA_OP_VUSE)
- {
- tree use = USE_FROM_PTR (use_p);
- tree sym = DECL_P (use) ? use : SSA_NAME_VAR (use);
-
if (symbol_marked_for_renaming (sym))
- mark_use_interesting (sym, stmt, bb, insert_phi_p);
+ mark_def_interesting (sym, stmt, bb, insert_phi_p);
}
}
/* Now visit all the blocks dominated by BB. */
for (son = first_dom_son (CDI_DOMINATORS, bb);
- son;
- son = next_dom_son (CDI_DOMINATORS, son))
+ son;
+ son = next_dom_son (CDI_DOMINATORS, son))
prepare_block_for_update (son, insert_phi_p);
}
FOR_EACH_IMM_USE_FAST (use_p, iter, name)
{
- tree stmt = USE_STMT (use_p);
- basic_block bb = bb_for_stmt (stmt);
+ gimple stmt = USE_STMT (use_p);
+ basic_block bb = gimple_bb (stmt);
- if (TREE_CODE (stmt) == PHI_NODE)
+ if (gimple_code (stmt) == GIMPLE_PHI)
{
int ix = PHI_ARG_INDEX_FROM_USE (use_p);
- edge e = PHI_ARG_EDGE (stmt, ix);
+ edge e = gimple_phi_arg_edge (stmt, ix);
mark_use_interesting (name, stmt, e->src, insert_phi_p);
}
else
static void
prepare_def_site_for (tree name, bool insert_phi_p)
{
- tree stmt;
+ gimple stmt;
basic_block bb;
gcc_assert (names_to_release == NULL
|| !bitmap_bit_p (names_to_release, SSA_NAME_VERSION (name)));
stmt = SSA_NAME_DEF_STMT (name);
- bb = bb_for_stmt (stmt);
+ bb = gimple_bb (stmt);
if (bb)
{
gcc_assert (bb->index < last_basic_block);
/* Dump all the names replaced by NAME to stderr. */
-void
+DEBUG_FUNCTION void
debug_names_replaced_by (tree name)
{
dump_names_replaced_by (stderr, name);
unsigned i = 0;
bitmap_iterator bi;
- if (!need_ssa_update_p ())
+ if (!need_ssa_update_p (cfun))
return;
if (new_ssa_names && sbitmap_first_set_bit (new_ssa_names) >= 0)
update_ssa_stats.num_virtual_symbols);
}
- if (syms_to_rename && !bitmap_empty_p (syms_to_rename))
+ if (!bitmap_empty_p (SYMS_TO_RENAME (cfun)))
{
- fprintf (file, "\n\nSymbols to be put in SSA form\n\n");
- EXECUTE_IF_SET_IN_BITMAP (syms_to_rename, 0, i, bi)
- {
- print_generic_expr (file, referenced_var (i), 0);
- fprintf (file, " ");
- }
+ fprintf (file, "\nSymbols to be put in SSA form\n");
+ dump_decl_set (file, SYMS_TO_RENAME (cfun));
+ fprintf (file, "\n");
}
if (names_to_release && !bitmap_empty_p (names_to_release))
{
- fprintf (file, "\n\nSSA names to release after updating the SSA web\n\n");
+ fprintf (file, "\nSSA names to release after updating the SSA web\n\n");
EXECUTE_IF_SET_IN_BITMAP (names_to_release, 0, i, bi)
{
print_generic_expr (file, ssa_name (i), 0);
fprintf (file, " ");
}
+ fprintf (file, "\n");
}
-
- fprintf (file, "\n\n");
}
/* Dump SSA update information to stderr. */
-void
+DEBUG_FUNCTION void
debug_update_ssa (void)
{
dump_update_ssa (stderr);
/* Initialize data structures used for incremental SSA updates. */
static void
-init_update_ssa (void)
+init_update_ssa (struct function *fn)
{
/* Reserve more space than the current number of names. The calls to
add_new_name_mapping are typically done after creating new SSA
sbitmap_zero (new_ssa_names);
repl_tbl = htab_create (20, repl_map_hash, repl_map_eq, repl_map_free);
- need_to_initialize_update_ssa_p = false;
- need_to_update_vops_p = false;
- syms_to_rename = BITMAP_ALLOC (NULL);
names_to_release = NULL;
memset (&update_ssa_stats, 0, sizeof (update_ssa_stats));
update_ssa_stats.virtual_symbols = BITMAP_ALLOC (NULL);
+ update_ssa_initialized_fn = fn;
}
htab_delete (repl_tbl);
repl_tbl = NULL;
- need_to_initialize_update_ssa_p = true;
- need_to_update_vops_p = false;
- BITMAP_FREE (syms_to_rename);
+ bitmap_clear (SYMS_TO_RENAME (update_ssa_initialized_fn));
BITMAP_FREE (update_ssa_stats.virtual_symbols);
if (names_to_release)
}
clear_ssa_name_info ();
+
+ fini_ssa_renamer ();
+
+ if (blocks_with_phis_to_rewrite)
+ EXECUTE_IF_SET_IN_BITMAP (blocks_with_phis_to_rewrite, 0, i, bi)
+ {
+ gimple_vec phis = VEC_index (gimple_vec, phis_to_rewrite, i);
+
+ VEC_free (gimple, heap, phis);
+ VEC_replace (gimple_vec, phis_to_rewrite, i, NULL);
+ }
+
+ BITMAP_FREE (blocks_with_phis_to_rewrite);
+ BITMAP_FREE (blocks_to_update);
+ update_ssa_initialized_fn = NULL;
}
update_ssa's tables. */
tree
-create_new_def_for (tree old_name, tree stmt, def_operand_p def)
+create_new_def_for (tree old_name, gimple stmt, def_operand_p def)
{
tree new_name = duplicate_ssa_name (old_name, stmt);
SET_DEF (def, new_name);
- if (TREE_CODE (stmt) == PHI_NODE)
+ if (gimple_code (stmt) == GIMPLE_PHI)
{
- edge e;
- edge_iterator ei;
- basic_block bb = bb_for_stmt (stmt);
+ basic_block bb = gimple_bb (stmt);
/* If needed, mark NEW_NAME as occurring in an abnormal PHI node. */
- FOR_EACH_EDGE (e, ei, bb->preds)
- if (e->flags & EDGE_ABNORMAL)
- {
- SSA_NAME_OCCURS_IN_ABNORMAL_PHI (new_name) = 1;
- break;
- }
+ SSA_NAME_OCCURS_IN_ABNORMAL_PHI (new_name) = bb_has_abnormal_pred (bb);
}
register_new_name_mapping (new_name, old_name);
update_ssa. */
void
-register_new_name_mapping (tree new, tree old)
+register_new_name_mapping (tree new_tree, tree old)
{
- if (need_to_initialize_update_ssa_p)
- init_update_ssa ();
+ if (!update_ssa_initialized_fn)
+ init_update_ssa (cfun);
- add_new_name_mapping (new, old);
+ gcc_assert (update_ssa_initialized_fn == cfun);
+
+ add_new_name_mapping (new_tree, old);
}
void
mark_sym_for_renaming (tree sym)
{
- if (need_to_initialize_update_ssa_p)
- init_update_ssa ();
-
- bitmap_set_bit (syms_to_rename, DECL_UID (sym));
-
- if (!is_gimple_reg (sym))
- need_to_update_vops_p = true;
+ bitmap_set_bit (SYMS_TO_RENAME (cfun), DECL_UID (sym));
}
bitmap_iterator bi;
unsigned i;
- if (bitmap_empty_p (set))
+ if (set == NULL || bitmap_empty_p (set))
return;
- if (need_to_initialize_update_ssa_p)
- init_update_ssa ();
-
- bitmap_ior_into (syms_to_rename, set);
-
EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi)
- if (!is_gimple_reg (referenced_var (i)))
- {
- need_to_update_vops_p = true;
- break;
- }
+ mark_sym_for_renaming (referenced_var (i));
}
-/* Return true if there is any work to be done by update_ssa. */
+/* Return true if there is any work to be done by update_ssa
+ for function FN. */
bool
-need_ssa_update_p (void)
+need_ssa_update_p (struct function *fn)
{
- return syms_to_rename || old_ssa_names || new_ssa_names;
+ gcc_assert (fn != NULL);
+ return (update_ssa_initialized_fn == fn
+ || (fn->gimple_df
+ && !bitmap_empty_p (SYMS_TO_RENAME (fn))));
}
+/* Return true if SSA name mappings have been registered for SSA updating. */
+
+bool
+name_mappings_registered_p (void)
+{
+ if (!update_ssa_initialized_fn)
+ return false;
+
+ gcc_assert (update_ssa_initialized_fn == cfun);
+
+ return repl_tbl && htab_elements (repl_tbl) > 0;
+}
/* Return true if name N has been registered in the replacement table. */
bool
-name_registered_for_update_p (tree n)
+name_registered_for_update_p (tree n ATTRIBUTE_UNUSED)
{
- if (!need_ssa_update_p ())
+ if (!update_ssa_initialized_fn)
return false;
- return is_new_name (n)
- || is_old_name (n)
- || symbol_marked_for_renaming (SSA_NAME_VAR (n));
+ gcc_assert (update_ssa_initialized_fn == cfun);
+
+ return is_new_name (n) || is_old_name (n);
}
unsigned i = 0;
bitmap ret;
sbitmap_iterator sbi;
-
+
+ gcc_assert (update_ssa_initialized_fn == NULL
+ || update_ssa_initialized_fn == cfun);
+
ret = BITMAP_ALLOC (NULL);
EXECUTE_IF_SET_IN_SBITMAP (old_ssa_names, 0, i, sbi)
bitmap_set_bit (ret, i);
void
release_ssa_name_after_update_ssa (tree name)
{
- gcc_assert (!need_to_initialize_update_ssa_p);
+ gcc_assert (cfun && update_ssa_initialized_fn == cfun);
if (names_to_release == NULL)
names_to_release = BITMAP_ALLOC (NULL);
This is slightly different than the regular PHI insertion
algorithm. The value of UPDATE_FLAGS controls how PHI nodes for
real names (i.e., GIMPLE registers) are inserted:
-
+
- If UPDATE_FLAGS == TODO_update_ssa, we are only interested in PHI
nodes inside the region affected by the block that defines VAR
and the blocks that define all its replacements. All these
names is not pruned. PHI nodes are inserted at every IDF block. */
static void
-insert_updated_phi_nodes_for (tree var, bitmap *dfs, bitmap blocks,
+insert_updated_phi_nodes_for (tree var, bitmap_head *dfs, bitmap blocks,
unsigned update_flags)
{
basic_block entry;
bitmap_iterator bi;
unsigned i;
-#if defined ENABLE_CHECKING
if (TREE_CODE (var) == SSA_NAME)
- gcc_assert (is_old_name (var));
+ gcc_checking_assert (is_old_name (var));
else
- gcc_assert (symbol_marked_for_renaming (var));
-#endif
+ gcc_checking_assert (symbol_marked_for_renaming (var));
/* Get all the definition sites for VAR. */
db = find_def_blocks_for (var);
return;
/* Compute the initial iterated dominance frontier. */
- idf = find_idf (db->def_blocks, dfs);
+ idf = compute_idf (db->def_blocks, dfs);
pruned_idf = BITMAP_ALLOC (NULL);
if (TREE_CODE (var) == SSA_NAME)
common dominator of all the definition blocks. */
entry = nearest_common_dominator_for_set (CDI_DOMINATORS,
db->def_blocks);
-
if (entry != ENTRY_BLOCK_PTR)
EXECUTE_IF_SET_IN_BITMAP (idf, 0, i, bi)
if (BASIC_BLOCK (i) != entry
are included in the region to be updated. The feeding blocks
are important to guarantee that the PHI arguments are renamed
properly. */
+
+ /* FIXME, this is not needed if we are updating symbols. We are
+ already starting at the ENTRY block anyway. */
bitmap_ior_into (blocks, pruned_idf);
EXECUTE_IF_SET_IN_BITMAP (pruned_idf, 0, i, bi)
{
if (!is_gimple_reg (ssa_name (i)))
RESET_BIT (old_ssa_names, i);
- bitmap_ior_into (syms_to_rename, update_ssa_stats.virtual_symbols);
+ mark_set_for_renaming (update_ssa_stats.virtual_symbols);
}
basic_block bb, start_bb;
bitmap_iterator bi;
unsigned i = 0;
- sbitmap tmp;
bool insert_phi_p;
sbitmap_iterator sbi;
- if (!need_ssa_update_p ())
+ if (!need_ssa_update_p (cfun))
return;
timevar_push (TV_TREE_SSA_INCREMENTAL);
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "\nUpdating SSA:\n");
+
+ if (!update_ssa_initialized_fn)
+ init_update_ssa (cfun);
+ gcc_assert (update_ssa_initialized_fn == cfun);
+
blocks_with_phis_to_rewrite = BITMAP_ALLOC (NULL);
if (!phis_to_rewrite)
- phis_to_rewrite = VEC_alloc (tree_vec, heap, last_basic_block);
+ phis_to_rewrite = VEC_alloc (gimple_vec, heap, last_basic_block);
blocks_to_update = BITMAP_ALLOC (NULL);
/* Ensure that the dominance information is up-to-date. */
removal, and there are no symbols to rename, then there's
nothing else to do. */
if (sbitmap_first_set_bit (new_ssa_names) < 0
- && bitmap_empty_p (syms_to_rename))
+ && bitmap_empty_p (SYMS_TO_RENAME (cfun)))
goto done;
}
/* Next, determine the block at which to start the renaming process. */
- if (!bitmap_empty_p (syms_to_rename))
+ if (!bitmap_empty_p (SYMS_TO_RENAME (cfun)))
{
/* If we have to rename some symbols from scratch, we need to
start the process at the root of the CFG. FIXME, it should
updating. For now this seems more work than it's worth. */
start_bb = ENTRY_BLOCK_PTR;
- /* Traverse the CFG looking for definitions and uses of symbols
- in SYMS_TO_RENAME. Mark interesting blocks and statements
- and set local live-in information for the PHI placement
- heuristics. */
+ /* Traverse the CFG looking for existing definitions and uses of
+ symbols in SYMS_TO_RENAME. Mark interesting blocks and
+ statements and set local live-in information for the PHI
+ placement heuristics. */
prepare_block_for_update (start_bb, insert_phi_p);
}
else
and for symbols in SYMS_TO_RENAME. */
if (insert_phi_p)
{
- bitmap *dfs;
+ bitmap_head *dfs;
/* If the caller requested PHI nodes to be added, compute
dominance frontiers. */
- dfs = XNEWVEC (bitmap, last_basic_block);
+ dfs = XNEWVEC (bitmap_head, last_basic_block);
FOR_EACH_BB (bb)
- dfs[bb->index] = BITMAP_ALLOC (NULL);
+ bitmap_initialize (&dfs[bb->index], &bitmap_default_obstack);
compute_dominance_frontiers (dfs);
if (sbitmap_first_set_bit (old_ssa_names) >= 0)
sbitmap_free (tmp);
}
- EXECUTE_IF_SET_IN_BITMAP (syms_to_rename, 0, i, bi)
- insert_updated_phi_nodes_for (referenced_var (i), dfs,
- blocks_to_update, update_flags);
+ EXECUTE_IF_SET_IN_BITMAP (SYMS_TO_RENAME (cfun), 0, i, bi)
+ insert_updated_phi_nodes_for (referenced_var (i), dfs, blocks_to_update,
+ update_flags);
FOR_EACH_BB (bb)
- BITMAP_FREE (dfs[bb->index]);
+ bitmap_clear (&dfs[bb->index]);
free (dfs);
/* Insertion of PHI nodes may have added blocks to the region.
EXECUTE_IF_SET_IN_SBITMAP (old_ssa_names, 0, i, sbi)
set_current_def (ssa_name (i), NULL_TREE);
- EXECUTE_IF_SET_IN_BITMAP (syms_to_rename, 0, i, bi)
+ EXECUTE_IF_SET_IN_BITMAP (SYMS_TO_RENAME (cfun), 0, i, bi)
set_current_def (referenced_var (i), NULL_TREE);
/* Now start the renaming process at START_BB. */
- tmp = sbitmap_alloc (last_basic_block);
- sbitmap_zero (tmp);
+ interesting_blocks = sbitmap_alloc (last_basic_block);
+ sbitmap_zero (interesting_blocks);
EXECUTE_IF_SET_IN_BITMAP (blocks_to_update, 0, i, bi)
- SET_BIT (tmp, i);
+ SET_BIT (interesting_blocks, i);
- rewrite_blocks (start_bb, REWRITE_UPDATE, tmp);
+ rewrite_blocks (start_bb, REWRITE_UPDATE);
- sbitmap_free (tmp);
+ sbitmap_free (interesting_blocks);
/* Debugging dumps. */
if (dump_file)
dump_update_ssa (dump_file);
- fprintf (dump_file, "Incremental SSA update started at block: %d\n\n",
+ fprintf (dump_file, "Incremental SSA update started at block: %d\n",
start_bb->index);
c = 0;
EXECUTE_IF_SET_IN_BITMAP (blocks_to_update, 0, i, bi)
c++;
fprintf (dump_file, "Number of blocks in CFG: %d\n", last_basic_block);
- fprintf (dump_file, "Number of blocks to update: %d (%3.0f%%)\n\n",
+ fprintf (dump_file, "Number of blocks to update: %d (%3.0f%%)\n",
c, PERCENT (c, last_basic_block));
if (dump_flags & TDF_DETAILS)
{
- fprintf (dump_file, "Affected blocks: ");
+ fprintf (dump_file, "Affected blocks:");
EXECUTE_IF_SET_IN_BITMAP (blocks_to_update, 0, i, bi)
- fprintf (dump_file, "%u ", i);
+ fprintf (dump_file, " %u", i);
fprintf (dump_file, "\n");
}
/* Free allocated memory. */
done:
- EXECUTE_IF_SET_IN_BITMAP (blocks_with_phis_to_rewrite, 0, i, bi)
- {
- tree_vec phis = VEC_index (tree_vec, phis_to_rewrite, i);
-
- VEC_free (tree, heap, phis);
- VEC_replace (tree_vec, phis_to_rewrite, i, NULL);
- }
- BITMAP_FREE (blocks_with_phis_to_rewrite);
- BITMAP_FREE (blocks_to_update);
delete_update_ssa ();
timevar_pop (TV_TREE_SSA_INCREMENTAL);
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