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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28424 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index 24fb24d3867bbef8334052d83be17976e08aae23..807768002b520e39d6787e359a6b1c11a67098c3 100644 (file)
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -239,3 +239,15 @@ ulong %bar() {
 it should be extended to do so.
 
 //===---------------------------------------------------------------------===//
+
+Turn this into a single byte store with no load (the other 3 bytes are
+unmodified):
+
+void %test(uint* %P) {
+       %tmp = load uint* %P
+        %tmp14 = or uint %tmp, 3305111552
+        %tmp15 = and uint %tmp14, 3321888767
+        store uint %tmp15, uint* %P
+        ret void
+}
+