From 5bcea612f4b6ed60aa2bc1c1c632dcb4c5b508b4 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Mon, 8 May 2006 21:24:21 +0000
Subject: add a note

llvm-svn: 28176
---
 llvm/lib/Target/X86/README.txt | 9 +++++++++
 1 file changed, 9 insertions(+)

(limited to 'llvm/lib/Target')

diff --git a/llvm/lib/Target/X86/README.txt b/llvm/lib/Target/X86/README.txt
index b8ec59ae364..af520afe1d8 100644
--- a/llvm/lib/Target/X86/README.txt
+++ b/llvm/lib/Target/X86/README.txt
@@ -1166,4 +1166,13 @@ pressure.  The scheduling issue is more pronounced without -static.
 The 2) marked instructions are the lowered form of the 1,undef,3,4 
 shufflevector.  It seems that there should be a better way to do it :)
 
+//===---------------------------------------------------------------------===//
+
+If shorter, we should use things like:
+movzwl %ax, %eax
+instead of:
+andl $65535, %EAX
+
+The former can also be used when the two-addressy nature of the 'and' would
+require a copy to be inserted (in X86InstrInfo::convertToThreeAddress).
 
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