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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26472 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index 4affd7c0844c4fcaaf88cd228924425be5948560..1ab1f16c71a225a18f39fdd00e950cc16734e580 100644 (file)
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -79,3 +79,10 @@ int f(unsigned x) {
 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25600
 http://gcc.gnu.org/ml/gcc-patches/2006-02/msg01492.html
 
+//===---------------------------------------------------------------------===//
+
+We should reassociate:
+int f(int a, int b){ return a * a + 2 * a * b + b * b; }
+into:
+int f(int a, int b) { return a * (a + 2 * b) + b * b; }
+to eliminate a multiply.