From: Guoqi Chen <chenguoqi@loongson.cn>
Date: Wed, 27 Aug 2025 06:45:58 +0000 (+0800)
Subject: internal/runtime/atomic: reset wrong jump target in Cas{,64} on loong64
X-Git-Tag: go1.26rc1~985
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=d4b17f58695337c7eefa9d066cc51a425842e491;p=gostls13.git

internal/runtime/atomic: reset wrong jump target in Cas{,64} on loong64

The implementation here needs to be consistent with ssa.OpLOONG64LoweredAtomicCas{32,64},
which was ignored in CL 613396.

Change-Id: I72e8d2318e0c1935cc3a35ab5098f8a84e48bcd5
Reviewed-on: https://go-review.googlesource.com/c/go/+/699395
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: sophie zhao <zhaoxiaolin@loongson.cn>
Reviewed-by: Meidan Li <limeidan@loongson.cn>
---

diff --git a/src/internal/runtime/atomic/atomic_loong64.s b/src/internal/runtime/atomic/atomic_loong64.s
index 95d3e2bdab..4215af24fe 100644
--- a/src/internal/runtime/atomic/atomic_loong64.s
+++ b/src/internal/runtime/atomic/atomic_loong64.s
@@ -19,7 +19,7 @@ TEXT ·Cas(SB), NOSPLIT, $0-17
 	MOVW	new+12(FP), R6
 
 	MOVBU	internal∕cpu·Loong64+const_offsetLOONG64HasLAMCAS(SB), R8
-	BEQ	R8, cas_again
+	BEQ	R8, ll_sc
 	MOVV	R5, R7  // backup old value
 	AMCASDBW	R6, (R4), R5
 	BNE	R7, R5, cas_fail0
@@ -30,6 +30,7 @@ cas_fail0:
 	MOVB	R0, ret+16(FP)
 	RET
 
+ll_sc:
 	// Implemented using the ll-sc instruction pair
 	DBAR	$0x14	// LoadAcquire barrier
 cas_again:
@@ -60,7 +61,7 @@ TEXT ·Cas64(SB), NOSPLIT, $0-25
 	MOVV	new+16(FP), R6
 
 	MOVBU	internal∕cpu·Loong64+const_offsetLOONG64HasLAMCAS(SB), R8
-	BEQ	R8, cas64_again
+	BEQ	R8, ll_sc_64
 	MOVV	R5, R7  // backup old value
 	AMCASDBV	R6, (R4), R5
 	BNE	R7, R5, cas64_fail0
@@ -71,6 +72,7 @@ cas64_fail0:
 	MOVB	R0, ret+24(FP)
 	RET
 
+ll_sc_64:
 	// Implemented using the ll-sc instruction pair
 	DBAR	$0x14
 cas64_again: