From: Chris Lattner <sabre@nondot.org>
Date: Mon, 21 Feb 2011 01:33:38 +0000 (+0000)
Subject: add an idiom that loop idiom could theoretically catch.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=477a98824aaa173e8b4c327a82426de5c1197923;p=oota-llvm.git

add an idiom that loop idiom could theoretically catch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126101 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index 4e14fbbb09b..bda764deffe 100644
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -287,6 +287,16 @@ unsigned int popcount(unsigned int input) {
   return count;
 }
 
+This should be recognized as CLZ:  rdar://8459039
+
+unsigned clz_a(unsigned a) {
+  int i;
+  for (i=0;i<32;i++)
+    if (a & (1<<(31-i)))
+      return i;
+  return 32;
+}
+
 This sort of thing should be added to the loop idiom pass.
 
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