From 964bf9d8f7224bc91023df9f0e4ed3694db44c62 Mon Sep 17 00:00:00 2001
From: cognet <cognet@FreeBSD.org>
Date: Sun, 7 Nov 2004 16:53:29 +0000
Subject: Implement ffs with clz for Xscale. Idea taken from:	NetBSD

---
 sys/libkern/arm/ffs.S | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

(limited to 'sys/libkern')

diff --git a/sys/libkern/arm/ffs.S b/sys/libkern/arm/ffs.S
index 4e6fe3d..6fe31b9 100644
--- a/sys/libkern/arm/ffs.S
+++ b/sys/libkern/arm/ffs.S
@@ -46,9 +46,12 @@ __FBSDID("$FreeBSD$");
  */
 
 ENTRY(ffs)
+
 	/* Standard trick to isolate bottom bit in r0 or 0 if r0 = 0 on entry */
  	rsb     r1, r0, #0
  	ands    r0, r0, r1
+#ifndef __XSCALE__
+	
 	/*
 	 * now r0 has at most one set bit, call this X
 	 * if X = 0, all further instructions are skipped
@@ -74,4 +77,8 @@ ENTRY(ffs)
 	.byte	10,  0,  0, 25,  0,  0, 21, 27  /* 40-47 */
 	.byte	31,  0,  0,  0,  0, 24,  0, 20  /* 48-55 */
 	.byte   30,  0, 23, 19, 29, 18, 17,  0  /* 56-63 */
-
+#else
+	clzne	r0, r0
+	rsbne	r0, r0, #32
+	mov	pc, lr
+#endif
-- 
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