https://gcc.gnu.org/g:59afd44ffb1bd55fc84b4a36107a9bdba708e9a0
commit r15-4422-g59afd44ffb1bd55fc84b4a36107a9bdba708e9a0
Author: Richard Biener <rguent...@suse.de>
Date: Thu Oct 17 14:27:13 2024 +0200
Relax boolean processing in vect_maybe_update_slp_op_vectype
The following makes VECTOR_BOOLEAN_TYPE_P processing consistent with
what we do without SLP. The original motivation for rejecting of
VECTOR_BOOLEAN_TYPE_P extern defs was bad code generation. But
the non-SLP codepath happily goes along - but always hits the
case of an uniform vector and this case specifically we can now
code-generate optimally. So the following allows single-lane
externs as well.
Requiring patterns to code-generate can have bad influence on
the vectorization factor though a prototype patch of mine shows
that generating vector compares externally isn't always trivial.
The patch fixes the gcc.dg/vect/vect-early-break_82.c FAIL on x86_64
when --param vect-force-slp=1 is in effect.
PR tree-optimization/117171
* tree-vect-stmts.cc (vect_maybe_update_slp_op_vectype):
Relax vect_external_def VECTOR_BOOLEAN_TYPE_P constraint.
Diff:
---
gcc/tree-vect-stmts.cc | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc
index 6967d50288e9..e7f14c3144c3 100644
--- a/gcc/tree-vect-stmts.cc
+++ b/gcc/tree-vect-stmts.cc
@@ -14290,9 +14290,12 @@ vect_maybe_update_slp_op_vectype (slp_tree op, tree
vectype)
if (SLP_TREE_VECTYPE (op))
return types_compatible_p (SLP_TREE_VECTYPE (op), vectype);
/* For external defs refuse to produce VECTOR_BOOLEAN_TYPE_P, those
- should be handled by patters. Allow vect_constant_def for now. */
+ should be handled by patters. Allow vect_constant_def for now
+ as well as the trivial single-lane uniform vect_external_def case
+ both of which we code-generate reasonably. */
if (VECTOR_BOOLEAN_TYPE_P (vectype)
- && SLP_TREE_DEF_TYPE (op) == vect_external_def)
+ && SLP_TREE_DEF_TYPE (op) == vect_external_def
+ && SLP_TREE_LANES (op) > 1)
return false;
SLP_TREE_VECTYPE (op) = vectype;
return true;
