From: Nick Craig-Wood <nick@craig-wood.com>
Date: Mon, 22 Jul 2013 23:29:25 +0000 (+1000)
Subject: runtime: Stop arm memmove corrupting its parameters
X-Git-Tag: go1.2rc2~972
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=f8fd77baa9e57b2de6b9c0e08a3de0a7a8ad8947;p=gostls13.git

runtime: Stop arm memmove corrupting its parameters

Change use of x+(SP) to access the stack frame into x-(SP)

Fixes #5925.

R=golang-dev, bradfitz, dave, remyoudompheng, nick, rsc
CC=dave cheney <dave, golang-dev
https://golang.org/cl/11647043
---

diff --git a/src/pkg/runtime/memmove_arm.s b/src/pkg/runtime/memmove_arm.s
index 562fc0fad1..ce8f9fd4d5 100644
--- a/src/pkg/runtime/memmove_arm.s
+++ b/src/pkg/runtime/memmove_arm.s
@@ -85,7 +85,7 @@ _b4aligned:				/* is source now aligned? */
 	BNE	_bunaligned
 
 	ADD	$31, R(TS), R(TMP)	/* do 32-byte chunks if possible */
-	MOVW	R(TS), savedts+4(SP)
+	MOVW	R(TS), savedts-4(SP)
 _b32loop:
 	CMP	R(TMP), R(TE)
 	BLS	_b4tail
@@ -95,7 +95,7 @@ _b32loop:
 	B	_b32loop
 
 _b4tail:				/* do remaining words if possible */
-	MOVW	savedts+4(SP), R(TS)
+	MOVW	savedts-4(SP), R(TS)
 	ADD	$3, R(TS), R(TMP)
 _b4loop:
 	CMP	R(TMP), R(TE)
@@ -130,7 +130,7 @@ _f4aligned:				/* is source now aligned? */
 	BNE	_funaligned
 
 	SUB	$31, R(TE), R(TMP)	/* do 32-byte chunks if possible */
-	MOVW	R(TE), savedte+4(SP)
+	MOVW	R(TE), savedte-4(SP)
 _f32loop:
 	CMP	R(TMP), R(TS)
 	BHS	_f4tail
@@ -140,7 +140,7 @@ _f32loop:
 	B	_f32loop
 
 _f4tail:
-	MOVW	savedte+4(SP), R(TE)
+	MOVW	savedte-4(SP), R(TE)
 	SUB	$3, R(TE), R(TMP)	/* do remaining words if possible */
 _f4loop:
 	CMP	R(TMP), R(TS)
@@ -182,7 +182,7 @@ _bunaligned:
 	BLS	_b1tail
 
 	BIC	$3, R(FROM)		/* align source */
-	MOVW	R(TS), savedts+4(SP)
+	MOVW	R(TS), savedts-4(SP)
 	MOVW	(R(FROM)), R(BR0)	/* prime first block register */
 
 _bu16loop:
@@ -206,7 +206,7 @@ _bu16loop:
 	B	_bu16loop
 
 _bu1tail:
-	MOVW	savedts+4(SP), R(TS)
+	MOVW	savedts-4(SP), R(TS)
 	ADD	R(OFFSET), R(FROM)
 	B	_b1tail
 
@@ -230,7 +230,7 @@ _funaligned:
 	BHS	_f1tail
 
 	BIC	$3, R(FROM)		/* align source */
-	MOVW	R(TE), savedte+4(SP)
+	MOVW	R(TE), savedte-4(SP)
 	MOVW.P	4(R(FROM)), R(FR3)	/* prime last block register, implicit write back */
 
 _fu16loop:
@@ -254,6 +254,6 @@ _fu16loop:
 	B	_fu16loop
 
 _fu1tail:
-	MOVW	savedte+4(SP), R(TE)
+	MOVW	savedte-4(SP), R(TE)
 	SUB	R(OFFSET), R(FROM)
 	B	_f1tail