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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35435 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 0 deletions

diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index 72965d0759..0bf8c4f8b4 100644
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -23,6 +23,14 @@ generic code.
 
 //===---------------------------------------------------------------------===//
 
+CodeGen/X86/lea-3.ll:test3 should be a single LEA, not a shift/move.  The X86
+backend knows how to three-addressify this shift, but it appears the register
+allocator isn't even asking it to do so in this case.  We should investigate
+why this isn't happening, it could have significant impact on other important
+cases for X86 as well.
+
+//===---------------------------------------------------------------------===//
+
 This should be one DIV/IDIV instruction, not a libcall:
 
 unsigned test(unsigned long long X, unsigned Y) {