[llvm-commits] [llvm] r74508 - /llvm/trunk/lib/Target/X86/README.txt

[Chris Lattner]

Author: lattner
Date: Mon Jun 29 23:20:46 2009
New Revision: 74508

URL: http://llvm.org/viewvc/llvm-project?rev=74508&view=rev
Log:
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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=74508&r1=74507&r2=74508&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/README.txt (original)
+++ llvm/trunk/lib/Target/X86/README.txt Mon Jun 29 23:20:46 2009
@@ -1932,3 +1932,23 @@
 instcombine.
 
 //===---------------------------------------------------------------------===//
+
+It looks like we don't have patterns (or they aren't matching) for adc with
+immediate:
+
+define i64 @f1(i64 %a) nounwind {
+   %tmp = sub i64 %a, 734439407618
+   ret i64 %tmp
+}
+$ llvm-as < t.ll | llc -march=x86
+
+_f1:
+	movl	4(%esp), %eax
+	addl	$4294967294, %eax
+	movl	$4294967124, %edx
+	adcl	8(%esp), %edx
+	ret
+
+There is no need to clobber %edx there.
+
+//===---------------------------------------------------------------------===//