From ef7b8d9e5a66f411b396b4ae8fc6b6640ffb2ba8 Mon Sep 17 00:00:00 2001
From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Fri, 25 Mar 2011 17:32:40 +0000
Subject: [PATCH] Add a note.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128286 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/README.txt | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index 33941f451a0..99616b47c84 100644
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -2238,4 +2238,23 @@ missed cases:
 
 //===---------------------------------------------------------------------===//
 
+define i1 @test1(i32 %x) nounwind {
+  %and = and i32 %x, 3
+  %cmp = icmp ult i32 %and, 2
+  ret i1 %cmp
+}
+
+Can be folded to (x & 2) == 0.
+
+define i1 @test2(i32 %x) nounwind {
+  %and = and i32 %x, 3
+  %cmp = icmp ugt i32 %and, 1
+  ret i1 %cmp
+}
 
+Can be folded to (x & 2) != 0.
+
+SimplifyDemandedBits shrinks the "and" constant to 2 but instcombine misses the
+icmp transform.
+
+//===---------------------------------------------------------------------===//
-- 
2.34.1