[llvm-commits] [llvm] r45343 - /llvm/trunk/lib/Target/X86/README.txt

[Chris Lattner]

Author: lattner
Date: Mon Dec 24 13:27:46 2007
New Revision: 45343

URL: http://llvm.org/viewvc/llvm-project?rev=45343&view=rev
Log:
add a simple hack


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

Modified: llvm/trunk/lib/Target/X86/README.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/README.txt?rev=45343&r1=45342&r2=45343&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/README.txt (original)
+++ llvm/trunk/lib/Target/X86/README.txt Mon Dec 24 13:27:46 2007
@@ -1573,3 +1573,15 @@
 
 //===---------------------------------------------------------------------===//
 
+We can fold a store into "zeroing a reg".  Instead of:
+
+xorl    %eax, %eax
+movl    %eax, 124(%esp)
+
+we should get:
+
+movl    $0, 124(%esp)
+
+if the flags of the xor are dead.
+
+//===---------------------------------------------------------------------===//