PATCH: Simplify AVX check

[H.J. Lu]

On Sat, Jul 23, 2011 at 10:15:55AM -0700, H.J. Lu wrote:
> Hi,
> 
> The only possible values in EAX are 0 or 6.  We can just subtract it by
> -1 to get the possible/negative value.
> 
> 

4 is also possible.  We just need to subtract it by 5 so that if EAX
is 0 or 4, we get a negative value and otherwise, we get 1.


H.J.
---
2011-07-24  H.J. Lu  <hongjiu.lu@intel.com>
 
	* sysdeps/x86_64/dl-trampoline.S (_dl_runtime_profile): Simplify
	AVX check.

diff --git a/sysdeps/x86_64/dl-trampoline.S b/sysdeps/x86_64/dl-trampoline.S
index 45a2dc2..f07df18 100644
--- a/sysdeps/x86_64/dl-trampoline.S
+++ b/sysdeps/x86_64/dl-trampoline.S
@@ -148,10 +148,8 @@ L(have_avx):
 	// Get XFEATURE_ENABLED_MASK
 	xgetbv
 	andl	$0x6, %eax
-	cmpl	$0x6, %eax
-	// Nonzero if SSE and AVX state saving is enabled.
-	sete	%al
-2:	leal	-1(%eax,%eax), %eax
+	// EAX is 6 if SSE and AVX state saving is enabled.
+2:	subl	$5, %eax
 	movl	%eax, L(have_avx)(%rip)
 	cmpl	$0, %eax
 
@@ -194,10 +192,8 @@ _dl_x86_64_save_sse:
 	// Get XFEATURE_ENABLED_MASK
 	xgetbv
 	andl	$0x6, %eax
-	cmpl	$0x6, %eax
-	// Nonzero if SSE and AVX state saving is enabled.
-	sete	%al
-2:	leal	-1(%eax,%eax), %eax
+	// EAX is 6 if SSE and AVX state saving is enabled.
+2:	subl	$5, %eax
 	movl	%eax, L(have_avx)(%rip)
 	cmpl	$0, %eax