/* Analysis Utilities for Loop Vectorization.
- Copyright (C) 2003,2004,2005 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.
#include "cfgloop.h"
#include "expr.h"
#include "optabs.h"
+#include "params.h"
#include "tree-chrec.h"
#include "tree-data-ref.h"
#include "tree-scalar-evolution.h"
#include "tree-vectorizer.h"
+#include "toplev.h"
/* Main analysis functions. */
static loop_vec_info vect_analyze_loop_form (struct loop *);
static bool vect_analyze_data_ref_dependences (loop_vec_info);
static bool vect_analyze_data_refs_alignment (loop_vec_info);
static bool vect_compute_data_refs_alignment (loop_vec_info);
-static void vect_enhance_data_refs_alignment (loop_vec_info);
+static bool vect_enhance_data_refs_alignment (loop_vec_info);
static bool vect_analyze_operations (loop_vec_info);
static bool vect_determine_vectorization_factor (loop_vec_info);
/* Utility functions for the analyses. */
static bool exist_non_indexing_operands_for_use_p (tree, tree);
-static void vect_mark_relevant (VEC(tree,heap) **, tree, bool, bool);
-static bool vect_stmt_relevant_p (tree, loop_vec_info, bool *, bool *);
static tree vect_get_loop_niters (struct loop *, tree *);
static bool vect_analyze_data_ref_dependence
(struct data_dependence_relation *, loop_vec_info);
static bool vect_compute_data_ref_alignment (struct data_reference *);
static bool vect_analyze_data_ref_access (struct data_reference *);
static bool vect_can_advance_ivs_p (loop_vec_info);
+static void vect_update_misalignment_for_peel
+ (struct data_reference *, struct data_reference *, int npeel);
/* Function vect_determine_vectorization_factor
for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
{
- tree stmt = bsi_stmt (si);
- unsigned int nunits;
- stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- tree vectype;
+ tree stmt = bsi_stmt (si);
+ unsigned int nunits;
+ stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
+ tree vectype;
- if (vect_print_dump_info (REPORT_DETAILS))
- {
- fprintf (vect_dump, "==> examining statement: ");
- print_generic_expr (vect_dump, stmt, TDF_SLIM);
- }
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "==> examining statement: ");
+ print_generic_expr (vect_dump, stmt, TDF_SLIM);
+ }
+
+ if (TREE_CODE (stmt) != GIMPLE_MODIFY_STMT)
+ continue;
+
+ gcc_assert (stmt_info);
- gcc_assert (stmt_info);
- /* skip stmts which do not need to be vectorized. */
- if (!STMT_VINFO_RELEVANT_P (stmt_info)
+ /* skip stmts which do not need to be vectorized. */
+ if (!STMT_VINFO_RELEVANT_P (stmt_info)
&& !STMT_VINFO_LIVE_P (stmt_info))
- {
- if (vect_print_dump_info (REPORT_DETAILS))
- fprintf (vect_dump, "skip.");
- continue;
- }
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "skip.");
+ continue;
+ }
- if (VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))))
- {
- if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
- {
- fprintf (vect_dump, "not vectorized: vector stmt in loop:");
- print_generic_expr (vect_dump, stmt, TDF_SLIM);
- }
- return false;
- }
+ if (!GIMPLE_STMT_P (stmt)
+ && VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))))
+ {
+ if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+ {
+ fprintf (vect_dump, "not vectorized: vector stmt in loop:");
+ print_generic_expr (vect_dump, 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 (STMT_VINFO_VECTYPE (stmt_info))
+ {
+ /* The only case when a vectype had been already set is for stmts
+ that contain a dataref, or for "pattern-stmts" (stmts generated
+ by the vectorizer to represent/replace a certain idiom). */
+ gcc_assert (STMT_VINFO_DATA_REF (stmt_info)
+ || is_pattern_stmt_p (stmt_info));
+ vectype = STMT_VINFO_VECTYPE (stmt_info);
+ }
+ else
+ {
+ gcc_assert (! STMT_VINFO_DATA_REF (stmt_info)
+ && !is_pattern_stmt_p (stmt_info));
+
+ /* We set the vectype according to the type of the result (lhs).
+ For stmts whose result-type is different than the type of the
+ arguments (e.g. demotion, promotion), vectype will be reset
+ appropriately (later). Note that we have to visit the smallest
+ datatype in this function, because that determines the VF.
+ If the samallest datatype in the loop is present only as the
+ rhs of a promotion operation - we'd miss it here.
+ However, in such a case, that a variable of this datatype
+ does not appear in the lhs anywhere in the loop, it shouldn't
+ affect the vectorization factor. */
+ scalar_type = TREE_TYPE (GIMPLE_STMT_OPERAND (stmt, 0));
- if (vect_print_dump_info (REPORT_DETAILS))
- {
- fprintf (vect_dump, "get vectype for scalar type: ");
- print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
- }
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "get vectype for scalar type: ");
+ print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
+ }
- vectype = get_vectype_for_scalar_type (scalar_type);
- if (!vectype)
- {
- if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
- {
- fprintf (vect_dump, "not vectorized: unsupported data-type ");
- print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
- }
- return false;
- }
- if (vect_print_dump_info (REPORT_DETAILS))
- {
- fprintf (vect_dump, "vectype: ");
- print_generic_expr (vect_dump, vectype, TDF_SLIM);
+ vectype = get_vectype_for_scalar_type (scalar_type);
+ if (!vectype)
+ {
+ if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+ {
+ fprintf (vect_dump,
+ "not vectorized: unsupported data-type ");
+ print_generic_expr (vect_dump, scalar_type, TDF_SLIM);
+ }
+ return false;
+ }
+ STMT_VINFO_VECTYPE (stmt_info) = vectype;
}
- STMT_VINFO_VECTYPE (stmt_info) = vectype;
- nunits = TYPE_VECTOR_SUBPARTS (vectype);
- if (vect_print_dump_info (REPORT_DETAILS))
- fprintf (vect_dump, "nunits = %d", nunits);
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "vectype: ");
+ print_generic_expr (vect_dump, vectype, TDF_SLIM);
+ }
- if (vectorization_factor)
- {
- /* FORNOW: don't allow mixed units.
- This restriction will be relaxed in the future. */
- if (nunits != vectorization_factor)
- {
- if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
- fprintf (vect_dump, "not vectorized: mixed data-types");
- return false;
- }
- }
- else
- vectorization_factor = nunits;
+ nunits = TYPE_VECTOR_SUBPARTS (vectype);
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "nunits = %d", nunits);
+
+ if (!vectorization_factor
+ || (nunits > vectorization_factor))
+ vectorization_factor = nunits;
- gcc_assert (GET_MODE_SIZE (TYPE_MODE (scalar_type))
- * vectorization_factor == UNITS_PER_SIMD_WORD);
}
}
if (STMT_VINFO_RELEVANT_P (stmt_info))
{
- gcc_assert (!VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))));
+ gcc_assert (GIMPLE_STMT_P (stmt)
+ || !VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (stmt))));
gcc_assert (STMT_VINFO_VECTYPE (stmt_info));
- ok = (vectorizable_operation (stmt, NULL, NULL)
+ ok = (vectorizable_type_promotion (stmt, NULL, NULL)
+ || vectorizable_type_demotion (stmt, NULL, NULL)
+ || vectorizable_operation (stmt, NULL, NULL)
|| vectorizable_assignment (stmt, NULL, NULL)
|| vectorizable_load (stmt, NULL, NULL)
+ || vectorizable_call (stmt, NULL, NULL)
|| vectorizable_store (stmt, NULL, NULL)
|| vectorizable_condition (stmt, NULL, NULL));
vectorization_factor, LOOP_VINFO_INT_NITERS (loop_vinfo));
if (LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
- && LOOP_VINFO_INT_NITERS (loop_vinfo) < vectorization_factor)
+ && ((LOOP_VINFO_INT_NITERS (loop_vinfo) < vectorization_factor)
+ || (LOOP_VINFO_INT_NITERS (loop_vinfo) <=
+ ((unsigned) (PARAM_VALUE (PARAM_MIN_VECT_LOOP_BOUND))
+ * vectorization_factor))))
{
if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
fprintf (vect_dump, "not vectorized: iteration count too small.");
}
if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)
- || LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0)
+ || LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0
+ || LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo))
{
if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump, "epilog loop required.");
"not vectorized: can't create epilog loop 1.");
return false;
}
- if (!slpeel_can_duplicate_loop_p (loop, loop->single_exit))
+ if (!slpeel_can_duplicate_loop_p (loop, single_exit (loop)))
{
if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
fprintf (vect_dump,
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)
+ if (TREE_CODE (GIMPLE_STMT_OPERAND (stmt, 0)) == SSA_NAME)
return false;
- operand = TREE_OPERAND (stmt, 1);
+ operand = GIMPLE_STMT_OPERAND (stmt, 1);
if (TREE_CODE (operand) != SSA_NAME)
return false;
}
+/* Function vect_insert_into_interleaving_chain.
+
+ Insert DRA into the interleaving chain of DRB according to DRA's INIT. */
+
+static void
+vect_insert_into_interleaving_chain (struct data_reference *dra,
+ struct data_reference *drb)
+{
+ tree prev, next, next_init;
+ stmt_vec_info stmtinfo_a = vinfo_for_stmt (DR_STMT (dra));
+ stmt_vec_info stmtinfo_b = vinfo_for_stmt (DR_STMT (drb));
+
+ prev = DR_GROUP_FIRST_DR (stmtinfo_b);
+ next = DR_GROUP_NEXT_DR (vinfo_for_stmt (prev));
+ while (next)
+ {
+ next_init = DR_INIT (STMT_VINFO_DATA_REF (vinfo_for_stmt (next)));
+ if (tree_int_cst_compare (next_init, DR_INIT (dra)) > 0)
+ {
+ /* Insert here. */
+ DR_GROUP_NEXT_DR (vinfo_for_stmt (prev)) = DR_STMT (dra);
+ DR_GROUP_NEXT_DR (stmtinfo_a) = next;
+ return;
+ }
+ prev = next;
+ next = DR_GROUP_NEXT_DR (vinfo_for_stmt (prev));
+ }
+
+ /* We got to the end of the list. Insert here. */
+ DR_GROUP_NEXT_DR (vinfo_for_stmt (prev)) = DR_STMT (dra);
+ DR_GROUP_NEXT_DR (stmtinfo_a) = NULL_TREE;
+}
+
+
+/* Function vect_update_interleaving_chain.
+
+ For two data-refs DRA and DRB that are a part of a chain interleaved data
+ accesses, update the interleaving chain. DRB's INIT is smaller than DRA's.
+
+ There are four possible cases:
+ 1. New stmts - both DRA and DRB are not a part of any chain:
+ FIRST_DR = DRB
+ NEXT_DR (DRB) = DRA
+ 2. DRB is a part of a chain and DRA is not:
+ no need to update FIRST_DR
+ no need to insert DRB
+ insert DRA according to init
+ 3. DRA is a part of a chain and DRB is not:
+ if (init of FIRST_DR > init of DRB)
+ FIRST_DR = DRB
+ NEXT(FIRST_DR) = previous FIRST_DR
+ else
+ insert DRB according to its init
+ 4. both DRA and DRB are in some interleaving chains:
+ choose the chain with the smallest init of FIRST_DR
+ insert the nodes of the second chain into the first one. */
+
+static void
+vect_update_interleaving_chain (struct data_reference *drb,
+ struct data_reference *dra)
+{
+ stmt_vec_info stmtinfo_a = vinfo_for_stmt (DR_STMT (dra));
+ stmt_vec_info stmtinfo_b = vinfo_for_stmt (DR_STMT (drb));
+ tree next_init, init_dra_chain, init_drb_chain, first_a, first_b;
+ tree node, prev, next, node_init, first_stmt;
+
+ /* 1. New stmts - both DRA and DRB are not a part of any chain. */
+ if (!DR_GROUP_FIRST_DR (stmtinfo_a) && !DR_GROUP_FIRST_DR (stmtinfo_b))
+ {
+ DR_GROUP_FIRST_DR (stmtinfo_a) = DR_STMT (drb);
+ DR_GROUP_FIRST_DR (stmtinfo_b) = DR_STMT (drb);
+ DR_GROUP_NEXT_DR (stmtinfo_b) = DR_STMT (dra);
+ return;
+ }
+
+ /* 2. DRB is a part of a chain and DRA is not. */
+ if (!DR_GROUP_FIRST_DR (stmtinfo_a) && DR_GROUP_FIRST_DR (stmtinfo_b))
+ {
+ DR_GROUP_FIRST_DR (stmtinfo_a) = DR_GROUP_FIRST_DR (stmtinfo_b);
+ /* Insert DRA into the chain of DRB. */
+ vect_insert_into_interleaving_chain (dra, drb);
+ return;
+ }
+
+ /* 3. DRA is a part of a chain and DRB is not. */
+ if (DR_GROUP_FIRST_DR (stmtinfo_a) && !DR_GROUP_FIRST_DR (stmtinfo_b))
+ {
+ tree old_first_stmt = DR_GROUP_FIRST_DR (stmtinfo_a);
+ tree init_old = DR_INIT (STMT_VINFO_DATA_REF (vinfo_for_stmt (
+ old_first_stmt)));
+ tree tmp;
+
+ if (tree_int_cst_compare (init_old, DR_INIT (drb)) > 0)
+ {
+ /* DRB's init is smaller than the init of the stmt previously marked
+ as the first stmt of the interleaving chain of DRA. Therefore, we
+ update FIRST_STMT and put DRB in the head of the list. */
+ DR_GROUP_FIRST_DR (stmtinfo_b) = DR_STMT (drb);
+ DR_GROUP_NEXT_DR (stmtinfo_b) = old_first_stmt;
+
+ /* Update all the stmts in the list to point to the new FIRST_STMT. */
+ tmp = old_first_stmt;
+ while (tmp)
+ {
+ DR_GROUP_FIRST_DR (vinfo_for_stmt (tmp)) = DR_STMT (drb);
+ tmp = DR_GROUP_NEXT_DR (vinfo_for_stmt (tmp));
+ }
+ }
+ else
+ {
+ /* Insert DRB in the list of DRA. */
+ vect_insert_into_interleaving_chain (drb, dra);
+ DR_GROUP_FIRST_DR (stmtinfo_b) = DR_GROUP_FIRST_DR (stmtinfo_a);
+ }
+ return;
+ }
+
+ /* 4. both DRA and DRB are in some interleaving chains. */
+ first_a = DR_GROUP_FIRST_DR (stmtinfo_a);
+ first_b = DR_GROUP_FIRST_DR (stmtinfo_b);
+ if (first_a == first_b)
+ return;
+ init_dra_chain = DR_INIT (STMT_VINFO_DATA_REF (vinfo_for_stmt (first_a)));
+ init_drb_chain = DR_INIT (STMT_VINFO_DATA_REF (vinfo_for_stmt (first_b)));
+
+ if (tree_int_cst_compare (init_dra_chain, init_drb_chain) > 0)
+ {
+ /* Insert the nodes of DRA chain into the DRB chain.
+ After inserting a node, continue from this node of the DRB chain (don't
+ start from the beginning. */
+ node = DR_GROUP_FIRST_DR (stmtinfo_a);
+ prev = DR_GROUP_FIRST_DR (stmtinfo_b);
+ first_stmt = first_b;
+ }
+ else
+ {
+ /* Insert the nodes of DRB chain into the DRA chain.
+ After inserting a node, continue from this node of the DRA chain (don't
+ start from the beginning. */
+ node = DR_GROUP_FIRST_DR (stmtinfo_b);
+ prev = DR_GROUP_FIRST_DR (stmtinfo_a);
+ first_stmt = first_a;
+ }
+
+ while (node)
+ {
+ node_init = DR_INIT (STMT_VINFO_DATA_REF (vinfo_for_stmt (node)));
+ next = DR_GROUP_NEXT_DR (vinfo_for_stmt (prev));
+ while (next)
+ {
+ next_init = DR_INIT (STMT_VINFO_DATA_REF (vinfo_for_stmt (next)));
+ if (tree_int_cst_compare (next_init, node_init) > 0)
+ {
+ /* Insert here. */
+ DR_GROUP_NEXT_DR (vinfo_for_stmt (prev)) = node;
+ DR_GROUP_NEXT_DR (vinfo_for_stmt (node)) = next;
+ prev = node;
+ break;
+ }
+ prev = next;
+ next = DR_GROUP_NEXT_DR (vinfo_for_stmt (prev));
+ }
+ if (!next)
+ {
+ /* We got to the end of the list. Insert here. */
+ DR_GROUP_NEXT_DR (vinfo_for_stmt (prev)) = node;
+ DR_GROUP_NEXT_DR (vinfo_for_stmt (node)) = NULL_TREE;
+ prev = node;
+ }
+ DR_GROUP_FIRST_DR (vinfo_for_stmt (node)) = first_stmt;
+ node = DR_GROUP_NEXT_DR (vinfo_for_stmt (node));
+ }
+}
+
+
+/* Function vect_equal_offsets.
+
+ Check if OFFSET1 and OFFSET2 are identical expressions. */
+
+static bool
+vect_equal_offsets (tree offset1, tree offset2)
+{
+ bool res0, res1;
+
+ STRIP_NOPS (offset1);
+ STRIP_NOPS (offset2);
+
+ if (offset1 == offset2)
+ return true;
+
+ if (TREE_CODE (offset1) != TREE_CODE (offset2)
+ || !BINARY_CLASS_P (offset1)
+ || !BINARY_CLASS_P (offset2))
+ return false;
+
+ res0 = vect_equal_offsets (TREE_OPERAND (offset1, 0),
+ TREE_OPERAND (offset2, 0));
+ res1 = vect_equal_offsets (TREE_OPERAND (offset1, 1),
+ TREE_OPERAND (offset2, 1));
+
+ return (res0 && res1);
+}
+
+
+/* Function vect_check_interleaving.
+
+ Check if DRA and DRB are a part of interleaving. In case they are, insert
+ DRA and DRB in an interleaving chain. */
+
+static void
+vect_check_interleaving (struct data_reference *dra,
+ struct data_reference *drb)
+{
+ HOST_WIDE_INT type_size_a, type_size_b, diff_mod_size, step, init_a, init_b;
+
+ /* Check that the data-refs have same first location (except init) and they
+ are both either store or load (not load and store). */
+ if ((DR_BASE_ADDRESS (dra) != DR_BASE_ADDRESS (drb)
+ && (TREE_CODE (DR_BASE_ADDRESS (dra)) != ADDR_EXPR
+ || TREE_CODE (DR_BASE_ADDRESS (drb)) != ADDR_EXPR
+ || TREE_OPERAND (DR_BASE_ADDRESS (dra), 0)
+ != TREE_OPERAND (DR_BASE_ADDRESS (drb),0)))
+ || !vect_equal_offsets (DR_OFFSET (dra), DR_OFFSET (drb))
+ || !tree_int_cst_compare (DR_INIT (dra), DR_INIT (drb))
+ || DR_IS_READ (dra) != DR_IS_READ (drb))
+ return;
+
+ /* Check:
+ 1. data-refs are of the same type
+ 2. their steps are equal
+ 3. the step is greater than the difference between data-refs' inits */
+ type_size_a = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (DR_REF (dra))));
+ type_size_b = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (DR_REF (drb))));
+
+ if (type_size_a != type_size_b
+ || tree_int_cst_compare (DR_STEP (dra), DR_STEP (drb)))
+ return;
+
+ init_a = TREE_INT_CST_LOW (DR_INIT (dra));
+ init_b = TREE_INT_CST_LOW (DR_INIT (drb));
+ step = TREE_INT_CST_LOW (DR_STEP (dra));
+
+ if (init_a > init_b)
+ {
+ /* If init_a == init_b + the size of the type * k, we have an interleaving,
+ and DRB is accessed before DRA. */
+ diff_mod_size = (init_a - init_b) % type_size_a;
+
+ if ((init_a - init_b) > step)
+ return;
+
+ if (diff_mod_size == 0)
+ {
+ vect_update_interleaving_chain (drb, dra);
+ if (vect_print_dump_info (REPORT_DR_DETAILS))
+ {
+ fprintf (vect_dump, "Detected interleaving ");
+ print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
+ fprintf (vect_dump, " and ");
+ print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
+ }
+ return;
+ }
+ }
+ else
+ {
+ /* If init_b == init_a + the size of the type * k, we have an
+ interleaving, and DRA is accessed before DRB. */
+ diff_mod_size = (init_b - init_a) % type_size_a;
+
+ if ((init_b - init_a) > step)
+ return;
+
+ if (diff_mod_size == 0)
+ {
+ vect_update_interleaving_chain (dra, drb);
+ if (vect_print_dump_info (REPORT_DR_DETAILS))
+ {
+ fprintf (vect_dump, "Detected interleaving ");
+ print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
+ fprintf (vect_dump, " and ");
+ print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
+ }
+ return;
+ }
+ }
+}
+
+
/* Function vect_analyze_data_ref_dependence.
Return TRUE if there (might) exist a dependence between a memory-reference
vect_analyze_data_ref_dependence (struct data_dependence_relation *ddr,
loop_vec_info loop_vinfo)
{
+ unsigned int i;
struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
int vectorization_factor = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
- int dist = 0;
- unsigned int loop_depth = 0;
- struct loop *loop_nest = loop;
struct data_reference *dra = DDR_A (ddr);
struct data_reference *drb = DDR_B (ddr);
stmt_vec_info stmtinfo_a = vinfo_for_stmt (DR_STMT (dra));
stmt_vec_info stmtinfo_b = vinfo_for_stmt (DR_STMT (drb));
+ int dra_size = GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dra))));
+ int drb_size = GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (drb))));
+ lambda_vector dist_v;
+ unsigned int loop_depth;
if (DDR_ARE_DEPENDENT (ddr) == chrec_known)
+ {
+ /* Independent data accesses. */
+ vect_check_interleaving (dra, drb);
+ return false;
+ }
+
+ if ((DR_IS_READ (dra) && DR_IS_READ (drb)) || dra == drb)
return false;
if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know)
return true;
}
- if (!DDR_DIST_VECT (ddr))
+ if (DDR_NUM_DIST_VECTS (ddr) == 0)
{
if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
{
return true;
}
- /* Find loop depth. */
- while (loop_nest && loop_nest->outer && loop_nest->outer->outer)
+ loop_depth = index_in_loop_nest (loop->num, DDR_LOOP_NEST (ddr));
+ for (i = 0; VEC_iterate (lambda_vector, DDR_DIST_VECTS (ddr), i, dist_v); i++)
{
- loop_nest = loop_nest->outer;
- loop_depth++;
- }
-
- dist = DDR_DIST_VECT (ddr)[loop_depth];
- if (vect_print_dump_info (REPORT_DR_DETAILS))
- fprintf (vect_dump, "dependence distance = %d.",dist);
-
- /* Same loop iteration. */
- if (dist % vectorization_factor == 0)
- {
- /* Two references with distance zero have the same alignment. */
- VEC_safe_push (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmtinfo_a), drb);
- VEC_safe_push (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmtinfo_b), dra);
- if (vect_print_dump_info (REPORT_ALIGNMENT))
- fprintf (vect_dump, "accesses have the same alignment.");
- if (vect_print_dump_info (REPORT_DR_DETAILS))
- {
- fprintf (vect_dump, "dependence distance modulo vf == 0 between ");
- print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
- fprintf (vect_dump, " and ");
- print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
- }
- return false;
- }
+ int dist = dist_v[loop_depth];
- if (abs (dist) >= vectorization_factor)
- {
- /* Dependence distance does not create dependence, as far as vectorization
- is concerned, in this case. */
if (vect_print_dump_info (REPORT_DR_DETAILS))
- fprintf (vect_dump, "dependence distance >= VF.");
- return false;
- }
-
- if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
- {
- fprintf (vect_dump,
- "not vectorized: possible dependence between data-refs ");
- print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
- fprintf (vect_dump, " and ");
- print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
+ fprintf (vect_dump, "dependence distance = %d.", dist);
+
+ /* Same loop iteration. */
+ if (dist % vectorization_factor == 0 && dra_size == drb_size)
+ {
+ /* Two references with distance zero have the same alignment. */
+ VEC_safe_push (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmtinfo_a), drb);
+ VEC_safe_push (dr_p, heap, STMT_VINFO_SAME_ALIGN_REFS (stmtinfo_b), dra);
+ if (vect_print_dump_info (REPORT_ALIGNMENT))
+ fprintf (vect_dump, "accesses have the same alignment.");
+ if (vect_print_dump_info (REPORT_DR_DETAILS))
+ {
+ fprintf (vect_dump, "dependence distance modulo vf == 0 between ");
+ print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
+ fprintf (vect_dump, " and ");
+ print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
+ }
+
+ /* For interleaving, mark that there is a read-write dependency if
+ necessary. We check before that one of the data-refs is store. */
+ if (DR_IS_READ (dra))
+ DR_GROUP_READ_WRITE_DEPENDENCE (stmtinfo_a) = true;
+ else
+ {
+ if (DR_IS_READ (drb))
+ DR_GROUP_READ_WRITE_DEPENDENCE (stmtinfo_b) = true;
+ }
+
+ continue;
+ }
+
+ if (abs (dist) >= vectorization_factor)
+ {
+ /* Dependence distance does not create dependence, as far as vectorization
+ is concerned, in this case. */
+ if (vect_print_dump_info (REPORT_DR_DETAILS))
+ fprintf (vect_dump, "dependence distance >= VF.");
+ continue;
+ }
+
+ if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+ {
+ fprintf (vect_dump,
+ "not vectorized: possible dependence between data-refs ");
+ print_generic_expr (vect_dump, DR_REF (dra), TDF_SLIM);
+ fprintf (vect_dump, " and ");
+ print_generic_expr (vect_dump, DR_REF (drb), TDF_SLIM);
+ }
+
+ return true;
}
-
- return true;
+
+ return false;
}
vect_analyze_data_ref_dependences (loop_vec_info loop_vinfo)
{
unsigned int i;
- varray_type ddrs = LOOP_VINFO_DDRS (loop_vinfo);
+ VEC (ddr_p, heap) *ddrs = LOOP_VINFO_DDRS (loop_vinfo);
+ struct data_dependence_relation *ddr;
if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump, "=== vect_analyze_dependences ===");
- for (i = 0; i < VARRAY_ACTIVE_SIZE (ddrs); i++)
- {
- struct data_dependence_relation *ddr = VARRAY_GENERIC_PTR (ddrs, i);
-
- if (vect_analyze_data_ref_dependence (ddr, loop_vinfo))
- return false;
- }
+ for (i = 0; VEC_iterate (ddr_p, ddrs, i, ddr); i++)
+ if (vect_analyze_data_ref_dependence (ddr, loop_vinfo))
+ return false;
return true;
}
if (!base_aligned)
{
- if (!vect_can_force_dr_alignment_p (base, TYPE_ALIGN (vectype)))
+ /* Do not change the alignment of global variables if
+ flag_section_anchors is enabled. */
+ if (!vect_can_force_dr_alignment_p (base, TYPE_ALIGN (vectype))
+ || (TREE_STATIC (base) && flag_section_anchors))
{
if (vect_print_dump_info (REPORT_DETAILS))
{
/* Modulo alignment. */
misalign = size_binop (TRUNC_MOD_EXPR, misalign, alignment);
- if (tree_int_cst_sgn (misalign) < 0)
+ if (!host_integerp (misalign, 1))
{
- /* Negative misalignment value. */
+ /* Negative or overflowed misalignment value. */
if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump, "unexpected misalign value");
return false;
}
- DR_MISALIGNMENT (dr) = tree_low_cst (misalign, 1);
+ DR_MISALIGNMENT (dr) = TREE_INT_CST_LOW (misalign);
if (vect_print_dump_info (REPORT_DETAILS))
{
/* 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. */
+ Return FALSE if a data reference is found that cannot be vectorized. */
static bool
vect_compute_data_refs_alignment (loop_vec_info loop_vinfo)
{
- varray_type datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
+ VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
+ struct data_reference *dr;
unsigned int i;
- for (i = 0; i < VARRAY_ACTIVE_SIZE (datarefs); i++)
+ for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
+ if (!vect_compute_data_ref_alignment (dr))
+ return false;
+
+ return true;
+}
+
+
+/* Function vect_update_misalignment_for_peel
+
+ DR - the data reference whose misalignment is to be adjusted.
+ DR_PEEL - the data reference whose misalignment is being made
+ zero in the vector loop by the peel.
+ NPEEL - the number of iterations in the peel loop if the misalignment
+ of DR_PEEL is known at compile time. */
+
+static void
+vect_update_misalignment_for_peel (struct data_reference *dr,
+ struct data_reference *dr_peel, int npeel)
+{
+ unsigned int i;
+ VEC(dr_p,heap) *same_align_drs;
+ struct data_reference *current_dr;
+ int dr_size = GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr))));
+ int dr_peel_size = GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr_peel))));
+ stmt_vec_info stmt_info = vinfo_for_stmt (DR_STMT (dr));
+ stmt_vec_info peel_stmt_info = vinfo_for_stmt (DR_STMT (dr_peel));
+
+ /* For interleaved data accesses the step in the loop must be multiplied by
+ the size of the interleaving group. */
+ if (DR_GROUP_FIRST_DR (stmt_info))
+ dr_size *= DR_GROUP_SIZE (vinfo_for_stmt (DR_GROUP_FIRST_DR (stmt_info)));
+ if (DR_GROUP_FIRST_DR (peel_stmt_info))
+ dr_peel_size *= DR_GROUP_SIZE (peel_stmt_info);
+
+ if (known_alignment_for_access_p (dr)
+ && known_alignment_for_access_p (dr_peel)
+ && (DR_MISALIGNMENT (dr) / dr_size ==
+ DR_MISALIGNMENT (dr_peel) / dr_peel_size))
{
- struct data_reference *dr = VARRAY_GENERIC_PTR (datarefs, i);
- if (!vect_compute_data_ref_alignment (dr))
- return false;
+ DR_MISALIGNMENT (dr) = 0;
+ return;
+ }
+
+ /* It can be assumed that the data refs with the same alignment as dr_peel
+ are aligned in the vector loop. */
+ same_align_drs
+ = STMT_VINFO_SAME_ALIGN_REFS (vinfo_for_stmt (DR_STMT (dr_peel)));
+ for (i = 0; VEC_iterate (dr_p, same_align_drs, i, current_dr); i++)
+ {
+ if (current_dr != dr)
+ continue;
+ gcc_assert (DR_MISALIGNMENT (dr) / dr_size ==
+ DR_MISALIGNMENT (dr_peel) / dr_peel_size);
+ DR_MISALIGNMENT (dr) = 0;
+ return;
+ }
+
+ if (known_alignment_for_access_p (dr)
+ && known_alignment_for_access_p (dr_peel))
+ {
+ DR_MISALIGNMENT (dr) += npeel * dr_size;
+ DR_MISALIGNMENT (dr) %= UNITS_PER_SIMD_WORD;
+ return;
}
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "Setting misalignment to -1.");
+ DR_MISALIGNMENT (dr) = -1;
+}
+
+
+/* Function vect_verify_datarefs_alignment
+
+ Return TRUE if all data references in the loop can be
+ handled with respect to alignment. */
+
+static bool
+vect_verify_datarefs_alignment (loop_vec_info loop_vinfo)
+{
+ VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
+ struct data_reference *dr;
+ enum dr_alignment_support supportable_dr_alignment;
+ unsigned int i;
+
+ for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
+ {
+ tree stmt = DR_STMT (dr);
+ stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
+
+ /* For interleaving, only the alignment of the first access matters. */
+ if (DR_GROUP_FIRST_DR (stmt_info)
+ && DR_GROUP_FIRST_DR (stmt_info) != stmt)
+ continue;
+
+ supportable_dr_alignment = vect_supportable_dr_alignment (dr);
+ if (!supportable_dr_alignment)
+ {
+ if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+ {
+ if (DR_IS_READ (dr))
+ fprintf (vect_dump,
+ "not vectorized: unsupported unaligned load.");
+ else
+ fprintf (vect_dump,
+ "not vectorized: unsupported unaligned store.");
+ }
+ return false;
+ }
+ if (supportable_dr_alignment != dr_aligned
+ && vect_print_dump_info (REPORT_ALIGNMENT))
+ fprintf (vect_dump, "Vectorizing an unaligned access.");
+ }
return true;
}
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. */
+ vectorized. This restriction will be relaxed.
+
+ 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 are the general steps involved in alignment enhancements:
-static void
-vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
-{
- varray_type loop_datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
- varray_type datarefs;
- VEC(dr_p,heap) *same_align_drs;
- struct data_reference *dr0 = NULL;
- struct data_reference *dr;
- unsigned int i, j;
- bool check_loads;
-
- /*
- 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
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;
}
if (p is aligned) {
- for (i = 3; i<N; i++){ # loop 3A
+ 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
}
}
- 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).
- */
+ 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). */
+
+static bool
+vect_enhance_data_refs_alignment (loop_vec_info loop_vinfo)
+{
+ VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
+ enum dr_alignment_support supportable_dr_alignment;
+ struct data_reference *dr0 = NULL;
+ struct data_reference *dr;
+ unsigned int i;
+ bool do_peeling = false;
+ bool do_versioning = false;
+ bool stat;
+ tree stmt;
+ stmt_vec_info stmt_info;
+
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "=== vect_enhance_data_refs_alignment ===");
+
+ /* While cost model enhancements are expected in the future, the high level
+ view of the code at this time is as follows:
+
+ A) If there is a misaligned write then see if peeling to align this write
+ can make all data references satisfy vect_supportable_dr_alignment.
+ If so, update data structures as needed and return true. Note that
+ at this time vect_supportable_dr_alignment is known to return false
+ for a a misaligned write.
+
+ B) If peeling wasn't possible and there is a data reference with an
+ unknown misalignment that does not satisfy vect_supportable_dr_alignment
+ then see if loop versioning checks can be used to make all data
+ references satisfy vect_supportable_dr_alignment. If so, update
+ data structures as needed and return true.
+
+ C) If neither peeling nor versioning were successful then return false if
+ any data reference does not satisfy vect_supportable_dr_alignment.
+
+ D) Return true (all data references satisfy vect_supportable_dr_alignment).
+
+ Note, Possibility 3 above (which is peeling and versioning together) is not
+ being done at this time. */
/* (1) Peeling to force alignment. */
misaligned store in the loop.
Rationale: misaligned stores are not yet supported.
- TODO: Use a better cost model. */
+ TODO: Use a cost model. */
- for (i = 0; i < VARRAY_ACTIVE_SIZE (loop_datarefs); i++)
+ for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
{
- dr0 = VARRAY_GENERIC_PTR (loop_datarefs, i);
- if (!DR_IS_READ (dr0) && !aligned_access_p (dr0))
- {
- LOOP_VINFO_UNALIGNED_DR (loop_vinfo) = dr0;
- LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo) = DR_MISALIGNMENT (dr0);
+ stmt = DR_STMT (dr);
+ stmt_info = vinfo_for_stmt (stmt);
+
+ /* For interleaving, only the alignment of the first access
+ matters. */
+ if (DR_GROUP_FIRST_DR (stmt_info)
+ && DR_GROUP_FIRST_DR (stmt_info) != stmt)
+ continue;
+
+ if (!DR_IS_READ (dr) && !aligned_access_p (dr))
+ {
+ if (DR_GROUP_FIRST_DR (stmt_info))
+ {
+ /* For interleaved access we peel only if number of iterations in
+ the prolog loop ({VF - misalignment}), is a multiple of the
+ number of the interleaved accesses. */
+ int elem_size, mis_in_elements;
+ int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
+
+ /* FORNOW: handle only known alignment. */
+ if (!known_alignment_for_access_p (dr))
+ {
+ do_peeling = false;
+ break;
+ }
+
+ elem_size = UNITS_PER_SIMD_WORD / vf;
+ mis_in_elements = DR_MISALIGNMENT (dr) / elem_size;
+
+ if ((vf - mis_in_elements) % DR_GROUP_SIZE (stmt_info))
+ {
+ do_peeling = false;
+ break;
+ }
+ }
+ dr0 = dr;
+ do_peeling = true;
break;
}
}
- /* (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.
-
- TODO: - consider accesses that are known to have the same
- alignment, even if that alignment is unknown. */
+ /* Often peeling for alignment will require peeling for loop-bound, which in
+ turn requires that we know how to adjust the loop ivs after the loop. */
+ if (!vect_can_advance_ivs_p (loop_vinfo))
+ do_peeling = false;
- if (LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo))
+ if (do_peeling)
{
int mis;
int npeel = 0;
if (known_alignment_for_access_p (dr0))
- {
- /* Since it's known at compile time, compute the number of iterations
- in the peeled loop (the peeling factor) for use in updating
- DR_MISALIGNMENT values. The peeling factor is the vectorization
- factor minus the misalignment as an element count. */
- mis = DR_MISALIGNMENT (dr0);
- mis /= GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr0))));
- npeel = LOOP_VINFO_VECT_FACTOR (loop_vinfo) - mis;
- }
+ {
+ /* Since it's known at compile time, compute the number of iterations
+ in the peeled loop (the peeling factor) for use in updating
+ DR_MISALIGNMENT values. The peeling factor is the vectorization
+ factor minus the misalignment as an element count. */
+ mis = DR_MISALIGNMENT (dr0);
+ mis /= GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr0))));
+ npeel = LOOP_VINFO_VECT_FACTOR (loop_vinfo) - mis;
+
+ /* For interleaved data access every iteration accesses all the
+ members of the group, therefore we divide the number of iterations
+ by the group size. */
+ stmt_info = vinfo_for_stmt (DR_STMT (dr0));
+ if (DR_GROUP_FIRST_DR (stmt_info))
+ npeel /= DR_GROUP_SIZE (stmt_info);
- datarefs = loop_datarefs;
- check_loads = false;
- for (j = 0; j < 2; j++)
- {
- for (i = 0; i < VARRAY_ACTIVE_SIZE (datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (datarefs, i);
-
- if (dr == dr0 || (!check_loads && DR_IS_READ (dr)))
- continue;
- if (known_alignment_for_access_p (dr)
- && DR_MISALIGNMENT (dr) == DR_MISALIGNMENT (dr0))
- DR_MISALIGNMENT (dr) = 0;
- else if (known_alignment_for_access_p (dr)
- && known_alignment_for_access_p (dr0))
- {
- int drsize =
- GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (DR_REF (dr))));
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "Try peeling by %d", npeel);
+ }
- DR_MISALIGNMENT (dr) += npeel * drsize;
- DR_MISALIGNMENT (dr) %= UNITS_PER_SIMD_WORD;
- }
- else
- DR_MISALIGNMENT (dr) = -1;
+ /* Ensure that all data refs can be vectorized after the peel. */
+ for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
+ {
+ int save_misalignment;
+
+ if (dr == dr0)
+ continue;
+
+ stmt = DR_STMT (dr);
+ stmt_info = vinfo_for_stmt (stmt);
+ /* For interleaving, only the alignment of the first access
+ matters. */
+ if (DR_GROUP_FIRST_DR (stmt_info)
+ && DR_GROUP_FIRST_DR (stmt_info) != stmt)
+ continue;
+
+ save_misalignment = DR_MISALIGNMENT (dr);
+ vect_update_misalignment_for_peel (dr, dr0, npeel);
+ supportable_dr_alignment = vect_supportable_dr_alignment (dr);
+ DR_MISALIGNMENT (dr) = save_misalignment;
+
+ if (!supportable_dr_alignment)
+ {
+ do_peeling = false;
+ break;
}
- check_loads = true;
}
- same_align_drs =
- STMT_VINFO_SAME_ALIGN_REFS (vinfo_for_stmt (DR_STMT (dr0)));
- for (i = 0; VEC_iterate (dr_p, same_align_drs, i, dr); i++)
+ if (do_peeling)
{
+ /* (1.2) Update the DR_MISALIGNMENT of each data reference DR_i.
+ If the misalignment of DR_i is identical to that of dr0 then set
+ DR_MISALIGNMENT (DR_i) to zero. If the misalignment of DR_i and
+ dr0 are known at compile time then increment DR_MISALIGNMENT (DR_i)
+ by the peeling factor times the element size of DR_i (MOD the
+ vectorization factor times the size). Otherwise, the
+ misalignment of DR_i must be set to unknown. */
+ for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
+ if (dr != dr0)
+ vect_update_misalignment_for_peel (dr, dr0, npeel);
+
+ LOOP_VINFO_UNALIGNED_DR (loop_vinfo) = dr0;
+ LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo) = DR_MISALIGNMENT (dr0);
+ DR_MISALIGNMENT (dr0) = 0;
+ if (vect_print_dump_info (REPORT_ALIGNMENT))
+ fprintf (vect_dump, "Alignment of access forced using peeling.");
+
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "Peeling for alignment will be applied.");
+
+ stat = vect_verify_datarefs_alignment (loop_vinfo);
+ gcc_assert (stat);
+ return stat;
+ }
+ }
+
+
+ /* (2) Versioning to force alignment. */
+
+ /* Try versioning if:
+ 1) flag_tree_vect_loop_version is TRUE
+ 2) optimize_size is FALSE
+ 3) there is at least one unsupported misaligned data ref with an unknown
+ misalignment, and
+ 4) all misaligned data refs with a known misalignment are supported, and
+ 5) the number of runtime alignment checks is within reason. */
+
+ do_versioning = flag_tree_vect_loop_version && (!optimize_size);
+
+ if (do_versioning)
+ {
+ for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
+ {
+ stmt = DR_STMT (dr);
+ stmt_info = vinfo_for_stmt (stmt);
+
+ /* For interleaving, only the alignment of the first access
+ matters. */
+ if (aligned_access_p (dr)
+ || (DR_GROUP_FIRST_DR (stmt_info)
+ && DR_GROUP_FIRST_DR (stmt_info) != stmt))
+ continue;
+
+ supportable_dr_alignment = vect_supportable_dr_alignment (dr);
+
+ if (!supportable_dr_alignment)
+ {
+ tree stmt;
+ int mask;
+ tree vectype;
+
+ if (known_alignment_for_access_p (dr)
+ || VEC_length (tree,
+ LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo))
+ >= (unsigned) PARAM_VALUE (PARAM_VECT_MAX_VERSION_CHECKS))
+ {
+ do_versioning = false;
+ break;
+ }
+
+ stmt = DR_STMT (dr);
+ vectype = STMT_VINFO_VECTYPE (vinfo_for_stmt (stmt));
+ gcc_assert (vectype);
+
+ /* The rightmost bits of an aligned address must be zeros.
+ Construct the mask needed for this test. For example,
+ GET_MODE_SIZE for the vector mode V4SI is 16 bytes so the
+ mask must be 15 = 0xf. */
+ mask = GET_MODE_SIZE (TYPE_MODE (vectype)) - 1;
+
+ /* FORNOW: use the same mask to test all potentially unaligned
+ references in the loop. The vectorizer currently supports
+ a single vector size, see the reference to
+ GET_MODE_NUNITS (TYPE_MODE (vectype)) where the
+ vectorization factor is computed. */
+ gcc_assert (!LOOP_VINFO_PTR_MASK (loop_vinfo)
+ || LOOP_VINFO_PTR_MASK (loop_vinfo) == mask);
+ LOOP_VINFO_PTR_MASK (loop_vinfo) = mask;
+ VEC_safe_push (tree, heap,
+ LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo),
+ DR_STMT (dr));
+ }
+ }
+
+ /* Versioning requires at least one misaligned data reference. */
+ if (VEC_length (tree, LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo)) == 0)
+ do_versioning = false;
+ else if (!do_versioning)
+ VEC_truncate (tree, LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo), 0);
+ }
+
+ if (do_versioning)
+ {
+ VEC(tree,heap) *may_misalign_stmts
+ = LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo);
+ tree stmt;
+
+ /* It can now be assumed that the data references in the statements
+ in LOOP_VINFO_MAY_MISALIGN_STMTS will be aligned in the version
+ of the loop being vectorized. */
+ for (i = 0; VEC_iterate (tree, may_misalign_stmts, i, stmt); i++)
+ {
+ stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
+ dr = STMT_VINFO_DATA_REF (stmt_info);
DR_MISALIGNMENT (dr) = 0;
+ if (vect_print_dump_info (REPORT_ALIGNMENT))
+ fprintf (vect_dump, "Alignment of access forced using versioning.");
}
- DR_MISALIGNMENT (dr0) = 0;
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "Versioning for alignment will be applied.");
+
+ /* Peeling and versioning can't be done together at this time. */
+ gcc_assert (! (do_peeling && do_versioning));
+
+ stat = vect_verify_datarefs_alignment (loop_vinfo);
+ gcc_assert (stat);
+ return stat;
}
+
+ /* This point is reached if neither peeling nor versioning is being done. */
+ gcc_assert (! (do_peeling || do_versioning));
+
+ stat = vect_verify_datarefs_alignment (loop_vinfo);
+ return stat;
}
/* Function vect_analyze_data_refs_alignment
Analyze the alignment of the data-references in the loop.
- FOR NOW: Until support for misaligned accesses is in place, only if all
- accesses are aligned can the loop be vectorized. This restriction will be
- relaxed. */
+ Return FALSE if a data reference is found that cannot be vectorized. */
static bool
vect_analyze_data_refs_alignment (loop_vec_info loop_vinfo)
{
- varray_type datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
- enum dr_alignment_support supportable_dr_alignment;
- unsigned int i;
-
if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump, "=== vect_analyze_data_refs_alignment ===");
-
- /* This pass may take place at function granularity instead of at loop
- granularity. */
-
if (!vect_compute_data_refs_alignment (loop_vinfo))
{
if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
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 (datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (datarefs, i);
- supportable_dr_alignment = vect_supportable_dr_alignment (dr);
- if (!supportable_dr_alignment)
- {
- if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
- {
- if (DR_IS_READ (dr))
- fprintf (vect_dump,
- "not vectorized: unsupported unaligned load.");
- else
- fprintf (vect_dump,
- "not vectorized: unsupported unaligned store.");
- }
- return false;
- }
- if (supportable_dr_alignment != dr_aligned
- && (vect_print_dump_info (REPORT_ALIGNMENT)))
- fprintf (vect_dump, "Vectorizing an unaligned access.");
- }
- if (LOOP_VINFO_UNALIGNED_DR (loop_vinfo)
- && vect_print_dump_info (REPORT_ALIGNMENT))
- fprintf (vect_dump, "Alignment of access forced using peeling.");
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 to be considered vectorizable. */
+ has to be consecutive to be considered vectorizable. */
static bool
vect_analyze_data_ref_access (struct data_reference *dr)
{
tree step = DR_STEP (dr);
+ HOST_WIDE_INT dr_step = TREE_INT_CST_LOW (step);
tree scalar_type = TREE_TYPE (DR_REF (dr));
+ HOST_WIDE_INT type_size = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (scalar_type));
+ tree stmt = DR_STMT (dr);
+ /* For interleaving, STRIDE is STEP counted in elements, i.e., the size of the
+ interleaving group (including gaps). */
+ HOST_WIDE_INT stride = dr_step / type_size;
- if (!step || tree_int_cst_compare (step, TYPE_SIZE_UNIT (scalar_type)))
+ if (!step)
{
if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "bad data-ref access");
+ return false;
+ }
+
+ /* Consecutive? */
+ if (!tree_int_cst_compare (step, TYPE_SIZE_UNIT (scalar_type)))
+ {
+ /* Mark that it is not interleaving. */
+ DR_GROUP_FIRST_DR (vinfo_for_stmt (stmt)) = NULL_TREE;
+ return true;
+ }
+
+ /* Not consecutive access is possible only if it is a part of interleaving. */
+ if (!DR_GROUP_FIRST_DR (vinfo_for_stmt (stmt)))
+ {
+ /* Check if it this DR is a part of interleaving, and is a single
+ element of the group that is accessed in the loop. */
+
+ /* Gaps are supported only for loads. STEP must be a multiple of the type
+ size. The size of the group must be a power of 2. */
+ if (DR_IS_READ (dr)
+ && (dr_step % type_size) == 0
+ && stride > 0
+ && exact_log2 (stride) != -1)
+ {
+ DR_GROUP_FIRST_DR (vinfo_for_stmt (stmt)) = stmt;
+ DR_GROUP_SIZE (vinfo_for_stmt (stmt)) = stride;
+ if (vect_print_dump_info (REPORT_DR_DETAILS))
+ {
+ fprintf (vect_dump, "Detected single element interleaving %d ",
+ DR_GROUP_SIZE (vinfo_for_stmt (stmt)));
+ print_generic_expr (vect_dump, DR_REF (dr), TDF_SLIM);
+ fprintf (vect_dump, " step ");
+ print_generic_expr (vect_dump, step, TDF_SLIM);
+ }
+ return true;
+ }
+ if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump, "not consecutive access");
return false;
}
+
+ if (DR_GROUP_FIRST_DR (vinfo_for_stmt (stmt)) == stmt)
+ {
+ /* First stmt in the interleaving chain. Check the chain. */
+ tree next = DR_GROUP_NEXT_DR (vinfo_for_stmt (stmt));
+ struct data_reference *data_ref = dr;
+ unsigned int count = 1;
+ tree next_step;
+ tree prev_init = DR_INIT (data_ref);
+ tree prev = stmt;
+ HOST_WIDE_INT diff, count_in_bytes;
+
+ while (next)
+ {
+ /* Skip same data-refs. In case that two or more stmts share data-ref
+ (supported only for loads), we vectorize only the first stmt, and
+ the rest get their vectorized loads from the the first one. */
+ if (!tree_int_cst_compare (DR_INIT (data_ref),
+ DR_INIT (STMT_VINFO_DATA_REF (
+ vinfo_for_stmt (next)))))
+ {
+ if (!DR_IS_READ (data_ref))
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "Two store stmts share the same dr.");
+ return false;
+ }
+
+ /* Check that there is no load-store dependecies for this loads
+ to prevent a case of load-store-load to the same location. */
+ if (DR_GROUP_READ_WRITE_DEPENDENCE (vinfo_for_stmt (next))
+ || DR_GROUP_READ_WRITE_DEPENDENCE (vinfo_for_stmt (prev)))
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump,
+ "READ_WRITE dependence in interleaving.");
+ return false;
+ }
+
+ /* For load use the same data-ref load. */
+ DR_GROUP_SAME_DR_STMT (vinfo_for_stmt (next)) = prev;
+
+ prev = next;
+ next = DR_GROUP_NEXT_DR (vinfo_for_stmt (next));
+ continue;
+ }
+ prev = next;
+
+ /* Check that all the accesses have the same STEP. */
+ next_step = DR_STEP (STMT_VINFO_DATA_REF (vinfo_for_stmt (next)));
+ if (tree_int_cst_compare (step, next_step))
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "not consecutive access in interleaving");
+ return false;
+ }
+
+ data_ref = STMT_VINFO_DATA_REF (vinfo_for_stmt (next));
+ /* Check that the distance between two accesses is equal to the type
+ size. Otherwise, we have gaps. */
+ diff = (TREE_INT_CST_LOW (DR_INIT (data_ref))
+ - TREE_INT_CST_LOW (prev_init)) / type_size;
+ if (!DR_IS_READ (data_ref) && diff != 1)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "interleaved store with gaps");
+ return false;
+ }
+ /* Store the gap from the previous member of the group. If there is no
+ gap in the access, DR_GROUP_GAP is always 1. */
+ DR_GROUP_GAP (vinfo_for_stmt (next)) = diff;
+
+ prev_init = DR_INIT (data_ref);
+ next = DR_GROUP_NEXT_DR (vinfo_for_stmt (next));
+ /* Count the number of data-refs in the chain. */
+ count++;
+ }
+
+ /* COUNT is the number of accesses found, we multiply it by the size of
+ the type to get COUNT_IN_BYTES. */
+ count_in_bytes = type_size * count;
+
+ /* Check that the size of the interleaving is not greater than STEP. */
+ if (dr_step < count_in_bytes)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "interleaving size is greater than step for ");
+ print_generic_expr (vect_dump, DR_REF (dr), TDF_SLIM);
+ }
+ return false;
+ }
+
+ /* Check that the size of the interleaving is equal to STEP for stores,
+ i.e., that there are no gaps. */
+ if (!DR_IS_READ (dr) && dr_step != count_in_bytes)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "interleaved store with gaps");
+ return false;
+ }
+
+ /* Check that STEP is a multiple of type size. */
+ if ((dr_step % type_size) != 0)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ {
+ fprintf (vect_dump, "step is not a multiple of type size: step ");
+ print_generic_expr (vect_dump, step, TDF_SLIM);
+ fprintf (vect_dump, " size ");
+ print_generic_expr (vect_dump, TYPE_SIZE_UNIT (scalar_type),
+ TDF_SLIM);
+ }
+ return false;
+ }
+
+ /* FORNOW: we handle only interleaving that is a power of 2. */
+ if (exact_log2 (stride) == -1)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "interleaving is not a power of 2");
+ return false;
+ }
+ DR_GROUP_SIZE (vinfo_for_stmt (stmt)) = stride;
+ }
return true;
}
vect_analyze_data_ref_accesses (loop_vec_info loop_vinfo)
{
unsigned int i;
- varray_type datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
+ VEC (data_reference_p, heap) *datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
+ struct data_reference *dr;
if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump, "=== vect_analyze_data_ref_accesses ===");
- for (i = 0; i < VARRAY_ACTIVE_SIZE (datarefs); i++)
- {
- struct data_reference *dr = VARRAY_GENERIC_PTR (datarefs, i);
- if (!vect_analyze_data_ref_access (dr))
- {
- if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
- fprintf (vect_dump, "not vectorized: complicated access pattern.");
- return false;
- }
- }
+ for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
+ if (!vect_analyze_data_ref_access (dr))
+ {
+ if (vect_print_dump_info (REPORT_UNVECTORIZED_LOOPS))
+ fprintf (vect_dump, "not vectorized: complicated access pattern.");
+ return false;
+ }
return true;
}
{
struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
unsigned int i;
- varray_type datarefs;
+ VEC (data_reference_p, heap) *datarefs;
+ struct data_reference *dr;
tree scalar_type;
if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump, "=== vect_analyze_data_refs ===");
- compute_data_dependences_for_loop (loop, false,
- &(LOOP_VINFO_DATAREFS (loop_vinfo)),
- &(LOOP_VINFO_DDRS (loop_vinfo)));
+ compute_data_dependences_for_loop (loop, true,
+ &LOOP_VINFO_DATAREFS (loop_vinfo),
+ &LOOP_VINFO_DDRS (loop_vinfo));
/* Go through the data-refs, check that the analysis succeeded. Update pointer
from stmt_vec_info struct to DR and vectype. */
datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
- for (i = 0; i < VARRAY_ACTIVE_SIZE (datarefs); i++)
+
+ for (i = 0; VEC_iterate (data_reference_p, datarefs, i, dr); i++)
{
- struct data_reference *dr = VARRAY_GENERIC_PTR (datarefs, i);
tree stmt;
stmt_vec_info stmt_info;
static void
vect_mark_relevant (VEC(tree,heap) **worklist, tree stmt,
- bool relevant_p, bool live_p)
+ enum vect_relevant relevant, bool live_p)
{
stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
- bool save_relevant_p = STMT_VINFO_RELEVANT_P (stmt_info);
+ enum vect_relevant save_relevant = STMT_VINFO_RELEVANT (stmt_info);
bool save_live_p = STMT_VINFO_LIVE_P (stmt_info);
if (vect_print_dump_info (REPORT_DETAILS))
- fprintf (vect_dump, "mark relevant %d, live %d.",relevant_p, live_p);
+ fprintf (vect_dump, "mark relevant %d, live %d.", relevant, live_p);
+
+ if (STMT_VINFO_IN_PATTERN_P (stmt_info))
+ {
+ tree pattern_stmt;
+
+ /* This is the last stmt in a sequence that was detected as a
+ pattern that can potentially be vectorized. Don't mark the stmt
+ as relevant/live because it's not going to vectorized.
+ Instead mark the pattern-stmt that replaces it. */
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "last stmt in pattern. don't mark relevant/live.");
+ pattern_stmt = STMT_VINFO_RELATED_STMT (stmt_info);
+ stmt_info = vinfo_for_stmt (pattern_stmt);
+ gcc_assert (STMT_VINFO_RELATED_STMT (stmt_info) == stmt);
+ save_relevant = STMT_VINFO_RELEVANT (stmt_info);
+ save_live_p = STMT_VINFO_LIVE_P (stmt_info);
+ stmt = pattern_stmt;
+ }
STMT_VINFO_LIVE_P (stmt_info) |= live_p;
- STMT_VINFO_RELEVANT_P (stmt_info) |= relevant_p;
+ if (relevant > STMT_VINFO_RELEVANT (stmt_info))
+ STMT_VINFO_RELEVANT (stmt_info) = relevant;
if (TREE_CODE (stmt) == PHI_NODE)
/* Don't put phi-nodes in the worklist. Phis that are marked relevant
or live will fail vectorization later on. */
return;
- if (STMT_VINFO_RELEVANT_P (stmt_info) == save_relevant_p
+ if (STMT_VINFO_RELEVANT (stmt_info) == save_relevant
&& STMT_VINFO_LIVE_P (stmt_info) == save_live_p)
{
if (vect_print_dump_info (REPORT_DETAILS))
static bool
vect_stmt_relevant_p (tree stmt, loop_vec_info loop_vinfo,
- bool *relevant_p, bool *live_p)
+ enum vect_relevant *relevant, bool *live_p)
{
struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
ssa_op_iter op_iter;
use_operand_p use_p;
def_operand_p def_p;
- *relevant_p = false;
+ *relevant = vect_unused_in_loop;
*live_p = false;
/* cond stmt other than loop exit cond. */
if (is_ctrl_stmt (stmt) && (stmt != LOOP_VINFO_EXIT_COND (loop_vinfo)))
- *relevant_p = true;
+ *relevant = vect_used_in_loop;
/* changing memory. */
if (TREE_CODE (stmt) != PHI_NODE)
{
if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump, "vec_stmt_relevant_p: stmt has vdefs.");
- *relevant_p = true;
+ *relevant = vect_used_in_loop;
}
/* uses outside the loop. */
/* We expect all such uses to be in the loop exit phis
(because of loop closed form) */
gcc_assert (TREE_CODE (USE_STMT (use_p)) == PHI_NODE);
- gcc_assert (bb == loop->single_exit->dest);
+ gcc_assert (bb == single_exit (loop)->dest);
*live_p = true;
}
}
}
- return (*live_p || *relevant_p);
+ return (*live_p || *relevant);
}
stmt_vec_info stmt_vinfo;
basic_block bb;
tree phi;
- bool relevant_p, live_p;
+ bool live_p;
+ enum vect_relevant relevant;
tree def, def_stmt;
enum vect_def_type dt;
print_generic_expr (vect_dump, phi, TDF_SLIM);
}
- if (vect_stmt_relevant_p (phi, loop_vinfo, &relevant_p, &live_p))
- vect_mark_relevant (&worklist, phi, relevant_p, live_p);
+ if (vect_stmt_relevant_p (phi, loop_vinfo, &relevant, &live_p))
+ vect_mark_relevant (&worklist, phi, relevant, live_p);
}
for (i = 0; i < nbbs; i++)
print_generic_expr (vect_dump, stmt, TDF_SLIM);
}
- if (vect_stmt_relevant_p (stmt, loop_vinfo, &relevant_p, &live_p))
- vect_mark_relevant (&worklist, stmt, relevant_p, live_p);
+ if (vect_stmt_relevant_p (stmt, loop_vinfo, &relevant, &live_p))
+ vect_mark_relevant (&worklist, stmt, relevant, live_p);
}
}
print_generic_expr (vect_dump, stmt, TDF_SLIM);
}
- /* Examine the USEs of STMT. For each ssa-name USE thta is defined
+ /* Examine the USEs of STMT. For each ssa-name USE that is defined
in the loop, mark the stmt that defines it (DEF_STMT) as
relevant/irrelevant and live/dead according to the liveness and
relevance properties of STMT.
ann = stmt_ann (stmt);
stmt_vinfo = vinfo_for_stmt (stmt);
- relevant_p = STMT_VINFO_RELEVANT_P (stmt_vinfo);
+ relevant = STMT_VINFO_RELEVANT (stmt_vinfo);
live_p = STMT_VINFO_LIVE_P (stmt_vinfo);
/* Generally, the liveness and relevance properties of STMT are
propagated to the DEF_STMTs of its USEs:
STMT_VINFO_LIVE_P (DEF_STMT_info) <-- live_p
- STMT_VINFO_RELEVANT_P (DEF_STMT_info) <-- relevant_p
+ STMT_VINFO_RELEVANT (DEF_STMT_info) <-- relevant
Exceptions:
the def_stmt of these uses we want to set liveness/relevance
as follows:
STMT_VINFO_LIVE_P (DEF_STMT_info) <-- false
- STMT_VINFO_RELEVANT_P (DEF_STMT_info) <-- true
+ STMT_VINFO_RELEVANT (DEF_STMT_info) <-- vect_used_by_reduction
because even though STMT is classified as live (since it defines a
value that is used across loop iterations) and irrelevant (since it
is not used inside the loop), it will be vectorized, and therefore
the corresponding DEF_STMTs need to marked as relevant.
+ We distinguish between two kinds of relevant stmts - those that are
+ used by a reduction computation, and those that are (also) used by
+ a regular computation. This allows us later on to identify stmts
+ that are used solely by a reduction, and therefore the order of
+ the results that they produce does not have to be kept.
*/
/* case 2.2: */
if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def)
{
- gcc_assert (!relevant_p && live_p);
- relevant_p = true;
+ gcc_assert (relevant == vect_unused_in_loop && live_p);
+ relevant = vect_used_by_reduction;
live_p = false;
}
&& TREE_CODE (def_stmt) == PHI_NODE)
continue;
- vect_mark_relevant (&worklist, def_stmt, relevant_p, live_p);
+ vect_mark_relevant (&worklist, def_stmt, relevant, live_p);
}
} /* while worklist */
/* Function vect_can_advance_ivs_p
- In case the number of iterations that LOOP iterates in unknown at compile
+ In case the number of iterations that LOOP iterates is 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
/* Analyze phi functions of the loop header. */
if (vect_print_dump_info (REPORT_DETAILS))
- fprintf (vect_dump, "=== vect_can_advance_ivs_p ===");
+ fprintf (vect_dump, "vect_can_advance_ivs_p:");
for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
{
if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump, "=== get_loop_niters ===");
- niters = number_of_iterations_in_loop (loop);
+ niters = number_of_exit_cond_executions (loop);
if (niters != NULL_TREE
&& niters != chrec_dont_know)
return NULL;
}
- if (!loop->single_exit
+ if (!single_exit (loop)
|| loop->num_nodes != 2
|| EDGE_COUNT (loop->header->preds) != 2)
{
if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
{
- if (!loop->single_exit)
+ if (!single_exit (loop))
fprintf (vect_dump, "not vectorized: multiple exits.");
else if (loop->num_nodes != 2)
fprintf (vect_dump, "not vectorized: too many BBs in loop.");
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 (!empty_block_p (loop->latch)
+ || phi_nodes (loop->latch))
{
if (vect_print_dump_info (REPORT_BAD_FORM_LOOPS))
fprintf (vect_dump, "not vectorized: unexpected loop form.");
}
/* Make sure there exists a single-predecessor exit bb: */
- if (!single_pred_p (loop->single_exit->dest))
+ if (!single_pred_p (single_exit (loop)->dest))
{
- edge e = loop->single_exit;
+ edge e = single_exit (loop);
if (!(e->flags & EDGE_ABNORMAL))
{
split_loop_exit_edge (e);
vect_analyze_scalar_cycles (loop_vinfo);
+ vect_pattern_recog (loop_vinfo);
+
/* Data-flow analysis to detect stmts that do not need to be vectorized. */
ok = vect_mark_stmts_to_be_vectorized (loop_vinfo);
return NULL;
}
+ /* Analyze the alignment of the data-refs in the loop.
+ Fail if a data reference is found that cannot be vectorized. */
+
+ ok = vect_analyze_data_refs_alignment (loop_vinfo);
+ if (!ok)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "bad data alignment.");
+ destroy_loop_vec_info (loop_vinfo);
+ return NULL;
+ }
+
ok = vect_determine_vectorization_factor (loop_vinfo);
if (!ok)
{
return NULL;
}
- /* Analyze the alignment of the data-refs in the loop.
- FORNOW: Only aligned accesses are handled. */
+ /* This pass will decide on using loop versioning and/or loop peeling in
+ order to enhance the alignment of data references in the loop. */
- ok = vect_analyze_data_refs_alignment (loop_vinfo);
+ ok = vect_enhance_data_refs_alignment (loop_vinfo);
if (!ok)
{
if (vect_print_dump_info (REPORT_DETAILS))
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