runtime: add atomicor8 for amd64p32

LGTM=khr
R=golang-codereviews, daniel.morsing, khr, rsc
CC=golang-codereviews, khr, rlh
https://golang.org/cl/131950043

diff --git a/src/pkg/runtime/asm_amd64p32.s b/src/pkg/runtime/asm_amd64p32.s
index 71ea4f385a222dd45619676955dd932210cb27e8..3e84d95d3f8747af2e442f2c6b8d4641b9fbaf81 100644 (file)
--- a/src/pkg/runtime/asm_amd64p32.s
+++ b/src/pkg/runtime/asm_amd64p32.s
@@ -660,6 +660,14 @@ TEXT runtime·atomicstore64(SB), NOSPLIT, $0-16
        XCHGQ   AX, 0(BX)
        RET
 
+// void        runtime·atomicor8(byte volatile*, byte);
+TEXT runtime·atomicor8(SB), NOSPLIT, $0-8
+       MOVL    ptr+0(FP), BX
+       MOVB    val+4(FP), AX
+       LOCK
+       ORB     AX, 0(BX)
+       RET
+
 // void jmpdefer(fn, sp);
 // called from deferreturn.
 // 1. pop the caller