It could cause weired spill in RA when register pressure is high.
Bootstrapped and regtested on x86_64-pc-linux-gnu{-m32,}.
Ok for trunk?
BTW, It's difficult to get a decent testcase for the issue since the spill
is not exposed in simple testcase.
gcc/ChangeLog:
PR target/117562
* config/i386/sse.md (vec_unpacks_hi_v4sf): Initialize
operands[2] with CONST0_RTX.
---
gcc/config/i386/sse.md | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/gcc/config/i386/sse.md b/gcc/config/i386/sse.md
index 72acd5bde5e..498a42d6e1e 100644
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -10424,7 +10424,10 @@ (define_expand "vec_unpacks_hi_v4sf"
(match_dup 2)
(parallel [(const_int 0) (const_int 1)]))))]
"TARGET_SSE2"
- "operands[2] = gen_reg_rtx (V4SFmode);")
+{
+ operands[2] = gen_reg_rtx (V4SFmode);
+ emit_move_insn (operands[2], CONST0_RTX (V4SFmode));
+})
(define_expand "vec_unpacks_hi_v8sf"
[(set (match_dup 2)
--
2.34.1
