From fc2f52128a106c99b0f2388f9954119dc29701fd Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Fri, 2 Mar 2007 05:04:52 +0000
Subject: [PATCH] add a note

llvm-svn: 34837
---
 llvm/lib/Target/X86/README.txt | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/llvm/lib/Target/X86/README.txt b/llvm/lib/Target/X86/README.txt
index 554c49beba1e..1c067f537177 100644
--- a/llvm/lib/Target/X86/README.txt
+++ b/llvm/lib/Target/X86/README.txt
@@ -920,3 +920,25 @@ LBB1_1:
 Though this probably isn't worth it.
 
 //===---------------------------------------------------------------------===//
+
+We need to teach the codegen to convert two-address INC instructions to LEA
+when the flags are dead.  For example, on X86-64, compile:
+
+int foo(int A, int B) {
+  return A+1;
+}
+
+to:
+
+_foo:
+        leal    1(%edi), %eax
+        ret
+
+instead of:
+
+_foo:
+        incl %edi
+        movl %edi, %eax
+        ret
+
+//===---------------------------------------------------------------------===//