With the extra GENERIC folding we now do to
(unsigned int) __v._M_value & 1 != (unsigned int) __v._M_value
we end up with a sign-extending conversion to unsigned int
rather than the sign-conversion to unsigned char we expect.
Relaxing that fixes the regression.
Bootstrapped and tested on x86_64-unknown-linux-gnu, OK?
Thanks,
Richard.
2022-05-23 Richard Biener <rguent...@suse.de>
PR tree-optimization/105629
* tree-ssa-phiopt.cc (spaceship_replacement): Allow
a sign-extending conversion.
---
gcc/tree-ssa-phiopt.cc | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc
index 8c9c46d41f1..e61d9736937 100644
--- a/gcc/tree-ssa-phiopt.cc
+++ b/gcc/tree-ssa-phiopt.cc
@@ -2217,7 +2217,7 @@ spaceship_replacement (basic_block cond_bb, basic_block
middle_bb,
if (!TYPE_UNSIGNED (ty2) || !INTEGRAL_TYPE_P (ty2))
return false;
- if (TYPE_PRECISION (ty1) != TYPE_PRECISION (ty2))
+ if (TYPE_PRECISION (ty1) > TYPE_PRECISION (ty2))
return false;
if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (orig_use_lhs))
return false;
--
2.35.3
