From: David Chase <drchase@google.com>
Date: Wed, 2 Jul 2025 18:28:10 +0000 (-0400)
Subject: [dev.simd] cmd/compile: fix the "always panic" code to actually panic
X-Git-Tag: go1.26rc1~147^2~203
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=72c39ef834;p=gostls13.git

[dev.simd] cmd/compile: fix the "always panic" code to actually panic

without this change, the intrinsics of non-constant immediates
just substitute a zero, which is wrong.

Change-Id: I2c39ebedcfb0d0d6c072f4434f393027c6f3f033
Reviewed-on: https://go-review.googlesource.com/c/go/+/685575
Reviewed-by: Junyang Shao <shaojunyang@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
---

diff --git a/src/cmd/compile/internal/ssagen/intrinsics.go b/src/cmd/compile/internal/ssagen/intrinsics.go
index 73e84077fd..c47b089815 100644
--- a/src/cmd/compile/internal/ssagen/intrinsics.go
+++ b/src/cmd/compile/internal/ssagen/intrinsics.go
@@ -1636,7 +1636,7 @@ func opLen4(op ssa.Op, t *types.Type) func(s *state, n *ir.CallExpr, args []*ssa
 
 func plainPanicSimdImm(s *state) {
 	cmp := s.newValue0(ssa.OpConstBool, types.Types[types.TBOOL])
-	cmp.AuxInt = 1
+	cmp.AuxInt = 0
 	// TODO: make this a standalone panic instead of reusing the overflow panic.
 	// Or maybe after we implement the switch table this will be obsolete anyway.
 	s.check(cmp, ir.Syms.Panicoverflow)