From: H. Peter Anvin <hpa@zytor.com>
Date: Mon, 26 May 2008 20:36:53 +0000 (-0700)
Subject: x86: string_32.h: workaround for broken gcc 4.0
X-Git-Tag: v2.6.27-rc1~1106^2~251^6~22
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=1a20d3ecf5c2a6435df2b756435b1eb1c657d45b;p=linux-2.6-omap-h63xx.git

x86: string_32.h: workaround for broken gcc 4.0

gcc 4.0 fails to allocate %eax for the pattern operand in the rep
store instructions used by memset; force it to do so by declaring a
register variable.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---

diff --git a/include/asm-x86/string_32.h b/include/asm-x86/string_32.h
index 8d0c593c441..193578cd1fd 100644
--- a/include/asm-x86/string_32.h
+++ b/include/asm-x86/string_32.h
@@ -267,11 +267,18 @@ void *__constant_c_and_count_memset(void *s, unsigned long pattern,
 	asm volatile("rep ; stosl"					\
 		     x							\
 		     : "=&c" (d0), "=&D" (d1)				\
-		     : "a" (pattern), "0" (count/4), "1" ((long)s)	\
+		     : "a" (eax), "0" (count/4), "1" ((long)s)	\
 		     : "memory")
 
 	{
 		int d0, d1;
+#if __GNUC__ == 4 && __GNUC_MINOR__ == 0
+		/* Workaround for broken gcc 4.0 */
+		register unsigned long eax asm("%eax") = pattern;
+#else
+		unsigned long eax = pattern;
+#endif
+
 		switch (count % 4) {
 		case 0:
 			COMMON("");