The expander and the insn pattern did not match, leading to
recognition failures in expand.
* config/aarch64/aarch64.md (*add<GPI>3_carryin): Accept zeros.
---
gcc/config/aarch64/aarch64.md | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
index 6fdab5f3402..b242f2b1c73 100644
--- a/gcc/config/aarch64/aarch64.md
+++ b/gcc/config/aarch64/aarch64.md
@@ -2606,16 +2606,17 @@
""
)
-;; Note that add with carry with two zero inputs is matched by cset,
-;; and that add with carry with one zero input is matched by cinc.
+;; While add with carry with two zero inputs will be folded to cset,
+;; and add with carry with one zero input will be folded to cinc,
+;; accept the zeros during initial expansion.
(define_insn "*add<mode>3_carryin"
[(set (match_operand:GPI 0 "register_operand" "=r")
(plus:GPI
(plus:GPI
(match_operand:GPI 3 "aarch64_carry_operation" "")
- (match_operand:GPI 1 "register_operand" "r"))
- (match_operand:GPI 2 "register_operand" "r")))]
+ (match_operand:GPI 1 "aarch64_reg_or_zero" "rZ"))
+ (match_operand:GPI 2 "aarch64_reg_or_zero" "rZ")))]
""
"adc\\t%<w>0, %<w>1, %<w>2"
[(set_attr "type" "adc_reg")]
--
2.20.1
