[llvm] r198552 - Add in a unittest for the one-use pattern matcher.

[Chandler Carruth]

Author: chandlerc
Date: Sun Jan  5 03:14:53 2014
New Revision: 198552

URL: http://llvm.org/viewvc/llvm-project?rev=198552&view=rev
Log:
Add in a unittest for the one-use pattern matcher.

Modified:
    llvm/trunk/unittests/IR/PatternMatch.cpp

Modified: llvm/trunk/unittests/IR/PatternMatch.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/IR/PatternMatch.cpp?rev=198552&r1=198551&r2=198552&view=diff
==============================================================================
--- llvm/trunk/unittests/IR/PatternMatch.cpp (original)
+++ llvm/trunk/unittests/IR/PatternMatch.cpp Sun Jan  5 03:14:53 2014
@@ -45,6 +45,26 @@ struct PatternMatchTest : ::testing::Tes
         BB(BasicBlock::Create(Ctx, "entry", F)), IRB(BB) {}
 };
 
+TEST_F(PatternMatchTest, OneUse) {
+  // Build up a little tree of values:
+  //
+  //   One  = (1 + 2) + 42
+  //   Two  = One + 42
+  //   Leaf = (Two + 8) + (Two + 13)
+  Value *One = IRB.CreateAdd(IRB.CreateAdd(IRB.getInt32(1), IRB.getInt32(2)),
+                             IRB.getInt32(42));
+  Value *Two = IRB.CreateAdd(One, IRB.getInt32(42));
+  Value *Leaf = IRB.CreateAdd(IRB.CreateAdd(Two, IRB.getInt32(8)),
+                              IRB.CreateAdd(Two, IRB.getInt32(13)));
+  Value *V;
+
+  EXPECT_TRUE(m_OneUse(m_Value(V)).match(One));
+  EXPECT_EQ(One, V);
+
+  EXPECT_FALSE(m_OneUse(m_Value()).match(Two));
+  EXPECT_FALSE(m_OneUse(m_Value()).match(Leaf));
+}
+
 TEST_F(PatternMatchTest, FloatingPointOrderedMin) {
   Type *FltTy = IRB.getFloatTy();
   Value *L = ConstantFP::get(FltTy, 1.0);