---

yaml --- r: 18221 b: refs/heads/master c: a3e4943 h: refs/heads/master i: 18219: 1364607 v: v3
git-mirror · Jan 10, 2006 · dbcef66 · dbcef66
1 parent 2846d60
commit dbcef66
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Showing 2 changed files with 11 additions and 2 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: b016450f9f603210239e1a91e3c28f17c310dcc7
+refs/heads/master: a3e49436867e6c7acc1b5eed21d30c88d156825b
diff --git a/trunk/include/asm-arm/byteorder.h b/trunk/include/asm-arm/byteorder.h
@@ -22,7 +22,16 @@ static inline __attribute_const__ __u32 ___arch__swab32(__u32 x)
 {
 	__u32 t;
 
-	t = x ^ ((x << 16) | (x >> 16));	/* eor r1,r0,r0,ror #16  */
+	if (__builtin_constant_p(x)) {
+		t = x ^ ((x << 16) | (x >> 16)); /* eor r1,r0,r0,ror #16 */
+	} else {
+		/*
+		 * The compiler needs a bit of a hint here to always do the
+		 * right thing and not screw it up to different degrees
+		 * depending on the gcc version.
+		 */
+		asm ("eor\t%0, %1, %1, ror #16" : "=r" (t) : "r" (x));
+	}
 	x = (x << 24) | (x >> 8);		/* mov r0,r0,ror #8      */
 	t &= ~0x00FF0000;			/* bic r1,r1,#0x00FF0000 */
 	x ^= (t >> 8);				/* eor r0,r0,r1,lsr #8   */