2 files changed, 134 insertions, 0 deletions
diff --git a/llvm/unittests/Analysis/CMakeLists.txt b/llvm/unittests/Analysis/CMakeLists.txt
index 06560cf14d4..743af1ddf85 100644
--- a/llvm/unittests/Analysis/CMakeLists.txt
+++ b/llvm/unittests/Analysis/CMakeLists.txt
@@ -13,4 +13,5 @@ add_llvm_unittest(AnalysisTests
   ScalarEvolutionTest.cpp
   MixedTBAATest.cpp
   ValueTrackingTest.cpp
+  UnrollAnalyzer.cpp
   )
diff --git a/llvm/unittests/Analysis/UnrollAnalyzer.cpp b/llvm/unittests/Analysis/UnrollAnalyzer.cpp
new file mode 100644
index 00000000000..79800ef1086
--- /dev/null
+++ b/llvm/unittests/Analysis/UnrollAnalyzer.cpp
@@ -0,0 +1,133 @@
+//===- UnrollAnalyzerTest.cpp - UnrollAnalyzer unit tests -----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/AsmParser/Parser.h"
+#include "llvm/IR/LegacyPassManager.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Analysis/LoopUnrollAnalyzer.h"
+#include "llvm/IR/Dominators.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+namespace llvm {
+void initializeUnrollAnalyzerTestPass(PassRegistry &);
+
+static SmallVector<DenseMap<Value *, Constant *>, 16> SimplifiedValuesVector;
+static unsigned TripCount = 0;
+
+namespace {
+struct UnrollAnalyzerTest : public FunctionPass {
+  static char ID;
+  bool runOnFunction(Function &F) override {
+    LoopInfo *LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
+    ScalarEvolution *SE = &getAnalysis<ScalarEvolutionWrapperPass>().getSE();
+
+    Function::iterator FI = F.begin();
+    FI++; // First basic block is entry - skip it.
+    BasicBlock *Header = &*FI++;
+    Loop *L = LI->getLoopFor(Header);
+
+    SimplifiedValuesVector.clear();
+    TripCount = SE->getSmallConstantTripCount(L, Header);
+    for (unsigned Iteration = 0; Iteration < TripCount; Iteration++) {
+      DenseMap<Value *, Constant *> SimplifiedValues;
+      UnrolledInstAnalyzer Analyzer(Iteration, SimplifiedValues, *SE);
+      for (Instruction &I : *Header)
+        Analyzer.visit(I);
+      SimplifiedValuesVector.push_back(SimplifiedValues);
+    }
+    return false;
+  }
+  void getAnalysisUsage(AnalysisUsage &AU) const override {
+    AU.addRequired<DominatorTreeWrapperPass>();
+    AU.addRequired<LoopInfoWrapperPass>();
+    AU.addRequired<ScalarEvolutionWrapperPass>();
+    AU.setPreservesAll();
+  }
+  UnrollAnalyzerTest() : FunctionPass(ID) {
+    initializeUnrollAnalyzerTestPass(*PassRegistry::getPassRegistry());
+  }
+};
+}
+
+char UnrollAnalyzerTest::ID = 0;
+
+std::unique_ptr<Module> makeLLVMModule(UnrollAnalyzerTest *P,
+                                       const char *ModuleStr) {
+  LLVMContext &C = getGlobalContext();
+  SMDiagnostic Err;
+  return parseAssemblyString(ModuleStr, Err, C);
+}
+
+TEST(UnrollAnalyzerTest, BasicSimplifications) {
+  const char *ModuleStr =
+      "target datalayout = \"e-m:o-i64:64-f80:128-n8:16:32:64-S128\"\n"
+      "define i64 @propagate_loop_phis() {\n"
+      "entry:\n"
+      "  br label %loop\n"
+      "loop:\n"
+      "  %iv = phi i64 [ 0, %entry ], [ %inc, %loop ]\n"
+      "  %x0 = phi i64 [ 0, %entry ], [ %x2, %loop ]\n"
+      "  %x1 = or i64 %x0, 1\n"
+      "  %x2 = or i64 %x1, 2\n"
+      "  %inc = add nuw nsw i64 %iv, 1\n"
+      "  %cond = icmp sge i64 %inc, 8\n"
+      "  br i1 %cond, label %loop.end, label %loop\n"
+      "loop.end:\n"
+      "  %x.lcssa = phi i64 [ %x2, %loop ]\n"
+      "  ret i64 %x.lcssa\n"
+      "}\n";
+  UnrollAnalyzerTest *P = new UnrollAnalyzerTest();
+  std::unique_ptr<Module> M = makeLLVMModule(P, ModuleStr);
+  legacy::PassManager Passes;
+  Passes.add(P);
+  Passes.run(*M);
+
+  // Perform checks
+  Module::iterator MI = M->begin();
+  Function *F = &*MI++;
+  Function::iterator FI = F->begin();
+  FI++; // First basic block is entry - skip it.
+  BasicBlock *Header = &*FI++;
+
+  BasicBlock::iterator BBI = Header->begin();
+  std::advance(BBI, 4);
+  Instruction *Y1 = &*BBI++;
+  Instruction *Y2 = &*BBI++;
+  // Check simplification expected on the 1st iteration.
+  // Check that "%inc = add nuw nsw i64 %iv, 1" is simplified to 1
+  auto I1 = SimplifiedValuesVector[0].find(Y1);
+  EXPECT_TRUE(I1 != SimplifiedValuesVector[0].end());
+  EXPECT_EQ(dyn_cast<ConstantInt>((*I1).second)->getZExtValue(), 1U);
+
+  // Check that "%cond = icmp sge i64 %inc, 10" is simplified to false
+  auto I2 = SimplifiedValuesVector[0].find(Y2);
+  EXPECT_TRUE(I2 != SimplifiedValuesVector[0].end());
+  EXPECT_FALSE(dyn_cast<ConstantInt>((*I2).second)->getZExtValue());
+
+  // Check simplification expected on the last iteration.
+  // Check that "%inc = add nuw nsw i64 %iv, 1" is simplified to 8
+  I1 = SimplifiedValuesVector[TripCount - 1].find(Y1);
+  EXPECT_TRUE(I1 != SimplifiedValuesVector[TripCount - 1].end());
+  EXPECT_EQ(dyn_cast<ConstantInt>((*I1).second)->getZExtValue(), TripCount);
+
+  // Check that "%cond = icmp sge i64 %inc, 10" is simplified to false
+  I2 = SimplifiedValuesVector[TripCount - 1].find(Y2);
+  EXPECT_TRUE(I2 != SimplifiedValuesVector[TripCount - 1].end());
+  EXPECT_TRUE(dyn_cast<ConstantInt>((*I2).second)->getZExtValue());
+}
+} // end namespace llvm
+
+INITIALIZE_PASS_BEGIN(UnrollAnalyzerTest, "unrollanalyzertestpass",
+                      "unrollanalyzertestpass", false, false)
+INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass)
+INITIALIZE_PASS_END(UnrollAnalyzerTest, "unrollanalyzertestpass",
+                    "unrollanalyzertestpass", false, false)