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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32347 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index 422d02165519247186122f17cae7f63028956842..c04e06fbfe0d078bf4e53ae454493c9dce48deee 100644 (file)
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -303,6 +303,16 @@ unsigned int swap_32(unsigned int v) {
   return v;
 }
 
+Nor is this (yes, it really is bswap):
+
+unsigned long reverse(unsigned v) {
+    unsigned t;
+    t = v ^ ((v << 16) | (v >> 16));
+    t &= ~0xff0000;
+    v = (v << 24) | (v >> 8);
+    return v ^ (t >> 8);
+}
+
 //===---------------------------------------------------------------------===//
 
 These should turn into single 16-bit (unaligned?) loads on little/big endian