[llvm-commits] [llvm] r42542 - /llvm/trunk/lib/Target/X86/README-SSE.txt

[Bill Wendling]

Author: void
Date: Tue Oct  2 14:55:05 2007
New Revision: 42542

URL: http://llvm.org/viewvc/llvm-project?rev=42542&view=rev
Log:
Micro-optimization -- missed LICM opportunity.

Modified:
    llvm/trunk/lib/Target/X86/README-SSE.txt

Modified: llvm/trunk/lib/Target/X86/README-SSE.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/README-SSE.txt?rev=42542&r1=42541&r2=42542&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/README-SSE.txt (original)
+++ llvm/trunk/lib/Target/X86/README-SSE.txt Tue Oct  2 14:55:05 2007
@@ -671,3 +671,27 @@
 
 //===---------------------------------------------------------------------===//
 
+In this loop:
+
+LBB4_6:	# bb47.preheader
+	shlw	$2, %si
+	decw	%si
+	movzwl	%si, %eax
+	incl	%eax
+	xorl	%ecx, %ecx
+LBB4_7:	# bb47
+	xorps	%xmm0, %xmm0            # (1)
+	movaps	%xmm0, (%edx)
+	movaps	%xmm0, 16(%edx)
+	addl	$32, %edx
+	incl	%ecx
+	cmpl	%eax, %ecx
+	jne	LBB4_7	# bb47
+LBB4_8:	# bb42.return_crit_edge
+	xorw	%si, %si
+	jmp	LBB4_12	# return
+
+The instruction at (1) can be moved out of the main body of the loop.
+
+//===---------------------------------------------------------------------===//
+