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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44637 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index af73658bb36215b0533468e7cd6f2dc819f66443..7705c1ba31e2473d13fa008153a924623455c6d6 100644 (file)
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -1532,3 +1532,23 @@ _test:
        ret
 
 This should just fldl directly from the input stack slot.
+
+//===---------------------------------------------------------------------===//
+
+This code:
+int foo (int x) { return (x & 65535) | 255; }
+
+Should compile into:
+
+_foo:
+        movzwl  4(%esp), %eax
+        orb     $-1, %al           ;; 'orl 255' is also fine :)
+        ret
+
+instead of:
+_foo:
+        movl    $255, %eax
+        orl     4(%esp), %eax
+        andl    $65535, %eax
+        ret
+