[parisc-linux] __arch__swab24()

[LaMont Jones]

The following patch implements __arch__swab24() optimally for hppa.

It also has the side effect of making some other things happier. :-)

Any comments before I commit it to 2.4 and 2.5?

lamont

Index: include/asm-parisc/byteorder.h
===================================================================
RCS file: /var/cvs/linux/include/asm-parisc/byteorder.h,v
retrieving revision 1.7
diff -u -r1.7 byteorder.h
--- include/asm-parisc/byteorder.h	8 Jul 2003 16:50:09 -0000	1.7
+++ include/asm-parisc/byteorder.h	1 Aug 2003 16:25:00 -0000
@@ -14,6 +14,17 @@
 	return x;
 }
 
+static __inline__ __const__ __u32 ___arch__swab24(__u32 x)
+{
+	unsigned int temp;
+	__asm__("shd %0, %0, 8, %1\n\t"		/* shift xabcxabc -> cxab */
+		"dep %1, 15, 8, %1\n\t"		/* deposit cxab -> cbab */
+		"shd %r0, %1, 8, %0"		/* shift 0000cbab -> 0cba */
+		: "=r" (x), "=&r" (temp)
+		: "0" (x));
+	return x;
+}
+
 static __inline__ __const__ __u32 ___arch__swab32(__u32 x)
 {
 	unsigned int temp;
@@ -63,6 +74,7 @@
 #endif
 
 #define __arch__swab16(x) ___arch__swab16(x)
+#define __arch__swab24(x) ___arch__swab24(x)
 #define __arch__swab32(x) ___arch__swab32(x)
 
 #endif /* __GNUC__ */