[llvm-commits] [llvm] r60632 - /llvm/trunk/lib/Target/X86/README.txt

[Chris Lattner]

Author: lattner
Date: Sat Dec  6 16:49:05 2008
New Revision: 60632

URL: http://llvm.org/viewvc/llvm-project?rev=60632&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=60632&r1=60631&r2=60632&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/README.txt (original)
+++ llvm/trunk/lib/Target/X86/README.txt Sat Dec  6 16:49:05 2008
@@ -1816,3 +1816,18 @@
 A similar code sequence works for division.
 
 //===---------------------------------------------------------------------===//
+
+These should compile to the same code, but the later codegen's to useless
+instructions on X86. This may be a trivial dag combine (GCC PR7061):
+
+struct s1 { unsigned char a, b; };
+unsigned long f1(struct s1 x) {
+    return x.a + x.b;
+}
+struct s2 { unsigned a: 8, b: 8; };
+unsigned long f2(struct s2 x) {
+    return x.a + x.b;
+}
+
+//===---------------------------------------------------------------------===//
+