Plus simplification in get_initial_def_for_reduction, avoiding some
of the + 0 adjustments I've seen created.
Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.
Richard.
2019-09-20 Richard Biener <rguent...@suse.de>
* tree-vect-loop.c (get_initial_def_for_reduction): Simplify,
avoid adjusting by + 0 or * 1.
(vect_create_epilog_for_reduction): Get reduction code only
when necessary. Deal with adjustment_def only when necessary.
Index: gcc/tree-vect-loop.c
===================================================================
--- gcc/tree-vect-loop.c (revision 275997)
+++ gcc/tree-vect-loop.c (working copy)
@@ -4003,8 +4003,10 @@ get_initial_def_for_reduction (stmt_vec_
gcc_assert (nested_in_vect_loop_p (loop, stmt_vinfo)
|| loop == (gimple_bb (stmt_vinfo->stmt))->loop_father);
- vect_reduction_type reduction_type
- = STMT_VINFO_VEC_REDUCTION_TYPE (stmt_vinfo);
+ /* ADJUSTMENT_DEF is NULL when called from
+ vect_create_epilog_for_reduction to vectorize double reduction. */
+ if (adjustment_def)
+ *adjustment_def = NULL;
switch (code)
{
@@ -4018,11 +4020,6 @@ get_initial_def_for_reduction (stmt_vec_
case MULT_EXPR:
case BIT_AND_EXPR:
{
- /* ADJUSTMENT_DEF is NULL when called from
- vect_create_epilog_for_reduction to vectorize double reduction. */
- if (adjustment_def)
- *adjustment_def = init_val;
-
if (code == MULT_EXPR)
{
real_init_val = dconst1;
@@ -4037,10 +4034,14 @@ get_initial_def_for_reduction (stmt_vec_
else
def_for_init = build_int_cst (scalar_type, int_init_val);
- if (adjustment_def)
- /* Option1: the first element is '0' or '1' as well. */
- init_def = gimple_build_vector_from_val (&stmts, vectype,
- def_for_init);
+ if (adjustment_def || operand_equal_p (def_for_init, init_val, 0))
+ {
+ /* Option1: the first element is '0' or '1' as well. */
+ if (!operand_equal_p (def_for_init, init_val, 0))
+ *adjustment_def = init_val;
+ init_def = gimple_build_vector_from_val (&stmts, vectype,
+ def_for_init);
+ }
else if (!TYPE_VECTOR_SUBPARTS (vectype).is_constant ())
{
/* Option2 (variable length): the first element is INIT_VAL. */
@@ -4064,16 +4065,8 @@ get_initial_def_for_reduction (stmt_vec_
case MAX_EXPR:
case COND_EXPR:
{
- if (adjustment_def)
- {
- *adjustment_def = NULL_TREE;
- if (reduction_type != COND_REDUCTION
- && reduction_type != EXTRACT_LAST_REDUCTION)
- {
- init_def = vect_get_vec_def_for_operand (init_val, stmt_vinfo);
- break;
- }
- }
+ gcc_assert (useless_type_conversion_p (TREE_TYPE (vectype),
+ TREE_TYPE (init_val)));
init_val = gimple_convert (&stmts, TREE_TYPE (vectype), init_val);
init_def = gimple_build_vector_from_val (&stmts, vectype, init_val);
}
@@ -4304,7 +4297,6 @@ vect_create_epilog_for_reduction (vec<tr
tree vec_dest;
tree new_temp = NULL_TREE, new_dest, new_name, new_scalar_dest;
gimple *epilog_stmt = NULL;
- enum tree_code code = gimple_assign_rhs_code (stmt_info->stmt);
gimple *exit_phi;
tree bitsize;
tree adjustment_def = NULL;
@@ -4645,12 +4637,6 @@ vect_create_epilog_for_reduction (vec<tr
gcc_assert (STMT_VINFO_IN_PATTERN_P (orig_stmt_info));
gcc_assert (STMT_VINFO_RELATED_STMT (orig_stmt_info) == stmt_info);
}
-
- code = gimple_assign_rhs_code (orig_stmt_info->stmt);
- /* For MINUS_EXPR the initial vector is [init_val,0,...,0], therefore,
- partial results are added and not subtracted. */
- if (code == MINUS_EXPR)
- code = PLUS_EXPR;
scalar_dest = gimple_assign_lhs (orig_stmt_info->stmt);
scalar_type = TREE_TYPE (scalar_dest);
@@ -4665,7 +4651,14 @@ vect_create_epilog_for_reduction (vec<tr
in the vectorized outer-loop, or reduced to a scalar result at the end of
the outer-loop. */
if (nested_in_vect_loop && !double_reduc)
- goto vect_finalize_reduction;
+ ;
+ else
+ {
+ enum tree_code code = gimple_assign_rhs_code (orig_stmt_info->stmt);
+ /* For MINUS_EXPR the initial vector is [init_val,0,...,0], therefore,
+ partial results are added and not subtracted. */
+ if (code == MINUS_EXPR)
+ code = PLUS_EXPR;
/* SLP reduction without reduction chain, e.g.,
# a1 = phi <a2, a0>
@@ -5352,12 +5345,7 @@ vect_create_epilog_for_reduction (vec<tr
scalar_results[0] = tmp;
}
}
-
-vect_finalize_reduction:
-
- if (double_reduc)
- loop = loop->inner;
-
+
/* 2.5 Adjust the final result by the initial value of the reduction
variable. (When such adjustment is not needed, then
'adjustment_def' is zero). For example, if code is PLUS we create:
@@ -5401,6 +5389,10 @@ vect_finalize_reduction:
new_phis[0] = epilog_stmt;
}
+ }
+
+ if (double_reduc)
+ loop = loop->inner;
/* 2.6 Handle the loop-exit phis. Replace the uses of scalar loop-exit
phis with new adjusted scalar results, i.e., replace use <s_out0>
