add a note


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22982 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt
index dc1bc57..649986e 100644
--- a/lib/Target/PowerPC/README.txt
+++ b/lib/Target/PowerPC/README.txt
@@ -51,3 +51,23 @@
 	b .LBBl42__2E_expand_function_8_674	; loopentry.24
 	b .LBBl42__2E_expand_function_8_42	; NewDefault
 	b .LBBl42__2E_expand_function_8_42	; NewDefault
+
+* Codegen this:
+
+   void test2(int X) {
+     if (X == 0x12345678) bar();
+   }
+
+    as:
+
+       xoris r0,r3,0x1234
+       cmpwi cr0,r0,0x5678
+       beq cr0,L6
+
+    not:
+
+        lis r2, 4660
+        ori r2, r2, 22136 
+        cmpw cr0, r3, r2  
+        bne .LBB_test2_2
+