The following avoids the multiplication by niters when the step
is equal.
Boostrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.
Richard.
2011-05-13 Richard Guenther <rguent...@suse.de>
PR tree-optimization/48172
* tree-vect-loop-manip.c (vect_vfa_segment_size): Avoid
multiplying by number of iterations for equal step.
(vect_create_cond_for_alias_checks): Likewise.
Index: gcc/tree-vect-loop-manip.c
===================================================================
*** gcc/tree-vect-loop-manip.c (revision 173704)
--- gcc/tree-vect-loop-manip.c (working copy)
*************** vect_create_cond_for_align_checks (loop_
*** 2353,2375 ****
Input:
DR: The data reference.
! VECT_FACTOR: vectorization factor.
! SCALAR_LOOP_NITERS: number of iterations.
Return an expression whose value is the size of segment which will be
accessed by DR. */
static tree
! vect_vfa_segment_size (struct data_reference *dr, int vect_factor,
! tree scalar_loop_niters)
{
tree segment_length;
segment_length = size_binop (MULT_EXPR,
fold_convert (sizetype, DR_STEP (dr)),
! size_int (vect_factor));
! segment_length = size_binop (MULT_EXPR,
! segment_length,
! fold_convert (sizetype, scalar_loop_niters));
if (vect_supportable_dr_alignment (dr, false)
== dr_explicit_realign_optimized)
{
--- 2353,2370 ----
Input:
DR: The data reference.
! LENGTH_FACTOR: segment length to consider.
Return an expression whose value is the size of segment which will be
accessed by DR. */
static tree
! vect_vfa_segment_size (struct data_reference *dr, tree length_factor)
{
tree segment_length;
segment_length = size_binop (MULT_EXPR,
fold_convert (sizetype, DR_STEP (dr)),
! fold_convert (sizetype, length_factor));
if (vect_supportable_dr_alignment (dr, false)
== dr_explicit_realign_optimized)
{
*************** vect_create_cond_for_alias_checks (loop_
*** 2417,2423 ****
ddr_p ddr;
unsigned int i;
! tree part_cond_expr;
/* Create expression
((store_ptr_0 + store_segment_length_0) < load_ptr_0)
--- 2412,2418 ----
ddr_p ddr;
unsigned int i;
! tree part_cond_expr, length_factor;
/* Create expression
((store_ptr_0 + store_segment_length_0) < load_ptr_0)
*************** vect_create_cond_for_alias_checks (loop_
*** 2465,2474 ****
vect_create_addr_base_for_vector_ref (stmt_b, cond_expr_stmt_list,
NULL_TREE, loop);
! segment_length_a = vect_vfa_segment_size (dr_a, vect_factor,
! scalar_loop_iters);
! segment_length_b = vect_vfa_segment_size (dr_b, vect_factor,
! scalar_loop_iters);
if (vect_print_dump_info (REPORT_DR_DETAILS))
{
--- 2460,2471 ----
vect_create_addr_base_for_vector_ref (stmt_b, cond_expr_stmt_list,
NULL_TREE, loop);
! if (!operand_equal_p (DR_STEP (dr_a), DR_STEP (dr_b), 0))
! length_factor = scalar_loop_iters;
! else
! length_factor = size_int (vect_factor);
! segment_length_a = vect_vfa_segment_size (dr_a, length_factor);
! segment_length_b = vect_vfa_segment_size (dr_b, length_factor);
if (vect_print_dump_info (REPORT_DR_DETAILS))
{
