The J constraint can invoke undefined behavior due to it taking the
negative of the ival if ival was HWI_MIN. The fix is simple as casting
to `unsigned HOST_WIDE_INT` before doing the negative of it. This
does that.
Committed as obvious after build/test for aarch64-linux-gnu.
gcc/ChangeLog:
PR target/100204
* config/aarch64/constraints.md (J): Cast to `unsigned HOST_WIDE_INT`
before taking the negative of it.
Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>
---
gcc/config/aarch64/constraints.md | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gcc/config/aarch64/constraints.md
b/gcc/config/aarch64/constraints.md
index 8566befd727..a2569cea510 100644
--- a/gcc/config/aarch64/constraints.md
+++ b/gcc/config/aarch64/constraints.md
@@ -118,7 +118,7 @@ (define_constraint "Uat"
(define_constraint "J"
"A constant that can be used with a SUB operation (once negated)."
(and (match_code "const_int")
- (match_test "aarch64_uimm12_shift (-ival)")))
+ (match_test "aarch64_uimm12_shift (- (unsigned HOST_WIDE_INT) ival)")))
;; We can't use the mode of a CONST_INT to determine the context in
;; which it is being used, so we must have a separate constraint for
--
2.39.3
