From f6661675729bcd9d2dd0149bbcbfccd3facb22f6 Mon Sep 17 00:00:00 2001
From: Ian Lance Taylor <iant@golang.org>
Date: Sun, 9 Nov 2014 18:55:36 -0800
Subject: [PATCH] cmd/5g: fix bit mask for div/mod routines clobbering R12

This patch is based only on reading the code.  I have not
tried to construct a test case.

Fixes #9077.

LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/172110043
---
 src/cmd/5g/reg.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/cmd/5g/reg.c b/src/cmd/5g/reg.c
index 27d9d3e8be..b78c268df5 100644
--- a/src/cmd/5g/reg.c
+++ b/src/cmd/5g/reg.c
@@ -230,7 +230,7 @@ regopt(Prog *firstp)
 
 		/* the mod/div runtime routines smash R12 */
 		if(p->as == ADIV || p->as == ADIVU || p->as == AMOD || p->as == AMODU)
-			r->set.b[z] |= RtoB(12);
+			r->set.b[0] |= RtoB(12);
 	}
 	if(firstr == R)
 		return;
-- 
2.50.0