[gcc(refs/vendors/riscv/heads/gcc-15-with-riscv-opts)] [PR rtl-optimization/122575] Fix mode on optimized IOR comparison
Jeff Law
law@gcc.gnu.org
Mon Nov 17 21:09:40 GMT 2025
https://gcc.gnu.org/g:b9f8770053cc6769dc72a3539349e98a5b756ddb
commit b9f8770053cc6769dc72a3539349e98a5b756ddb
Author: Jeff Law <jlaw@ventanamicro.com>
Date: Mon Nov 17 10:40:46 2025 -0700
[PR rtl-optimization/122575] Fix mode on optimized IOR comparison
As Andrew P recognized, we were using the wrong mode when simplifying certain
equality tests like (eq (ior (ne x 0 (y)). Sam took Andrew's suggestion and
verified it fixed the problem he was stumbling over.
So even though I haven't recreated the problem, I'm reasonably confident we've
got the right fix. I've bootstrapped and regression tested on x86.
PR rtl-optimization/122575
gcc/
* simplify-rtx.cc (simplify_context::simplify_relational_operation_1):
Use correct mode for simplified IOR expression inside equality
conditional.
(cherry picked from commit 2e1d74b27283b5c20b0e1611c358dbf4e62db54f)
Diff:
---
gcc/simplify-rtx.cc | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/gcc/simplify-rtx.cc b/gcc/simplify-rtx.cc
index 1b32f0137568..a9091add76ef 100644
--- a/gcc/simplify-rtx.cc
+++ b/gcc/simplify-rtx.cc
@@ -6379,10 +6379,10 @@ simplify_context::simplify_relational_operation_1 (rtx_code code,
/* only enters if op1 is 0 */
/* Verify IOR operand is NE */
&& GET_CODE (XEXP (op0, 0)) == NE
- /* Verfiy second NE operand is 0 */
+ /* Verify second NE operand is 0 */
&& XEXP (XEXP (op0, 0), 1) == CONST0_RTX (mode))
{
- rtx t = gen_rtx_IOR (mode, XEXP (XEXP (op0, 0), 0), XEXP (op0, 1));
+ rtx t = gen_rtx_IOR (cmp_mode, XEXP (XEXP (op0, 0), 0), XEXP (op0, 1));
t = gen_rtx_fmt_ee (code, mode, t, CONST0_RTX (mode));
return t;
}
More information about the Gcc-cvs
mailing list