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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27954 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index 5812512..a4611b2 100644
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -1123,3 +1123,10 @@
 
 //===---------------------------------------------------------------------===//
 
+We generate significantly worse code for this than GCC:
+http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21150
+http://gcc.gnu.org/bugzilla/attachment.cgi?id=8701
+
+There is also one case we do worse on PPC.
+
+//===---------------------------------------------------------------------===//