From b34487dcbac342512502894abee21d1dc874c767 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Sun, 8 Mar 2009 01:54:43 +0000
Subject: [PATCH] add a note.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66359 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/X86/README.txt | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index e8c2561d417..c4746d0c756 100644
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -1818,3 +1818,25 @@ LBB1_1:	## bb1
 	jne	LBB1_1	## bb1
 
 //===---------------------------------------------------------------------===//
+
+test/CodeGen/X86/2009-03-07-FPConstSelect.ll compiles to:
+
+_f:
+	xorl	%eax, %eax
+	cmpl	$0, 4(%esp)
+	movl	$4, %ecx
+	cmovne	%eax, %ecx
+	flds	LCPI1_0(%ecx)
+	ret
+
+we should recognize cmov of 0 and a power of two and compile it into a 
+setcc+shift.  This would give us something like:
+
+_f:
+	xorl %eax,%eax
+	cmpl	$0, 4(%esp)
+	seteq  %al
+	flds	LCPI1_0(%ecx, %eax,4)
+	ret
+
+//===---------------------------------------------------------------------===//
-- 
2.11.0