xf86-video-ati: Branch 'master'

[Alex Deucher]

 src/radeon_exa.c    |    9 ++++++++-
 src/radeon_render.c |    9 ++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

New commits:
commit 17cd42ed31814ba329a6a68edd0d75390a7da40e
Author: Matt Turner <mattst88 at gmail.com>
Date:   Wed Mar 19 18:17:10 2008 -0400

    Enable BSR in Log2 functions
    
    This patch edits RADEONLog2 and ATILog2 to use the x86 BSR instruction instead
    of looping through bits. It should provide a somewhat of a speed increase in
    this function on x86 and AMD64 architectures.
    
    Note: the BSR instruction was added with the 80386 CPU and is therefore not
    compatible with earlier CPUs, though I highly doubt it's even possible to use a
    286 in conjunction with a Radeon.
    
    The inline assembly also works with Intel's compiler (icc).

diff --git a/src/radeon_exa.c b/src/radeon_exa.c
index 4da4841..a6ededa 100644
--- a/src/radeon_exa.c
+++ b/src/radeon_exa.c
@@ -99,10 +99,17 @@ static __inline__ int
 RADEONLog2(int val)
 {
 	int bits;
-
+#if (defined __i386__ || defined __x86_64__) && (defined __GNUC__)
+	__asm volatile("bsrl	%1, %0"
+		: "=r" (bits)
+		: "c" (val)
+	);
+	return bits;
+#else
 	for (bits = 0; val != 0; val >>= 1, ++bits)
 		;
 	return bits - 1;
+#endif
 }
 
 static __inline__ CARD32 F_TO_DW(float val)
diff --git a/src/radeon_render.c b/src/radeon_render.c
index a80d136..950753c 100644
--- a/src/radeon_render.c
+++ b/src/radeon_render.c
@@ -250,10 +250,17 @@ static __inline__ int
 ATILog2(int val)
 {
 	int bits;
-
+#if (defined __i386__ || defined __x86_64__) && (defined __GNUC__)
+	__asm volatile("bsrl	%1, %0"
+		: "=r" (bits)
+		: "c" (val)
+	);
+	return bits;
+#else
 	for (bits = 0; val != 0; val >>= 1, ++bits)
 		;
 	return bits - 1;
+#endif
 }
 
 static void