The product of two chrec's can always be represented as a chrec.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141066 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 159 insertions, 7 deletions

diff --git a/unittests/Analysis/ScalarEvolutionTest.cpp b/unittests/Analysis/ScalarEvolutionTest.cpp
index a09cb1c..ea5aeb3 100644
--- a/unittests/Analysis/ScalarEvolutionTest.cpp
+++ b/unittests/Analysis/ScalarEvolutionTest.cpp
@@ -8,20 +8,35 @@
 //===----------------------------------------------------------------------===//
 
 #include <llvm/Analysis/ScalarEvolutionExpressions.h>
+#include <llvm/Analysis/LoopInfo.h>
 #include <llvm/GlobalVariable.h>
 #include <llvm/Constants.h>
 #include <llvm/LLVMContext.h>
 #include <llvm/Module.h>
 #include <llvm/PassManager.h>
+#include <llvm/ADT/SmallVector.h>
 #include "gtest/gtest.h"
 
 namespace llvm {
 namespace {
 
-TEST(ScalarEvolutionsTest, SCEVUnknownRAUW) {
+// We use this fixture to ensure that we clean up ScalarEvolution before
+// deleting the PassManager.
+class ScalarEvolutionsTest : public testing::Test {
+protected:
+  ScalarEvolutionsTest() : M("", Context), SE(*new ScalarEvolution) {}
+  ~ScalarEvolutionsTest() {
+    // Manually clean up, since we allocated new SCEV objects after the
+    // pass was finished.
+    SE.releaseMemory();
+  }
   LLVMContext Context;
-  Module M("world", Context);
+  Module M;
+  PassManager PM;
+  ScalarEvolution &SE;
+};
 
+TEST_F(ScalarEvolutionsTest, SCEVUnknownRAUW) {
   FunctionType *FTy = FunctionType::get(Type::getVoidTy(Context),
                                               std::vector<Type *>(), false);
   Function *F = cast<Function>(M.getOrInsertFunction("f", FTy));
@@ -35,8 +50,6 @@ TEST(ScalarEvolutionsTest, SCEVUnknownRAUW) {
   Value *V2 = new GlobalVariable(M, Ty, false, GlobalValue::ExternalLinkage, Init, "V2");
 
   // Create a ScalarEvolution and "run" it so that it gets initialized.
-  PassManager PM;
-  ScalarEvolution &SE = *new ScalarEvolution();
   PM.add(&SE);
   PM.run(M);
 
@@ -72,10 +85,149 @@ TEST(ScalarEvolutionsTest, SCEVUnknownRAUW) {
   EXPECT_EQ(cast<SCEVUnknown>(M0->getOperand(1))->getValue(), V0);
   EXPECT_EQ(cast<SCEVUnknown>(M1->getOperand(1))->getValue(), V0);
   EXPECT_EQ(cast<SCEVUnknown>(M2->getOperand(1))->getValue(), V0);
+}
+
+TEST_F(ScalarEvolutionsTest, SCEVMultiplyAddRecs) {
+  Type *Ty = Type::getInt32Ty(Context);
+  SmallVector<Type *, 10> Types;
+  Types.append(10, Ty);
+  FunctionType *FTy = FunctionType::get(Type::getVoidTy(Context), Types, false);
+  Function *F = cast<Function>(M.getOrInsertFunction("f", FTy));
+  BasicBlock *BB = BasicBlock::Create(Context, "entry", F);
+  ReturnInst::Create(Context, 0, BB);
+
+  // Create a ScalarEvolution and "run" it so that it gets initialized.
+  PM.add(&SE);
+  PM.run(M);
+
+  // It's possible to produce an empty loop through the default constructor,
+  // but you can't add any blocks to it without a LoopInfo pass.
+  Loop L;
+  const_cast<std::vector<BasicBlock*>&>(L.getBlocks()).push_back(BB);
+
+  Function::arg_iterator AI = F->arg_begin();
+  SmallVector<const SCEV *, 5> A;
+  A.push_back(SE.getSCEV(&*AI++));
+  A.push_back(SE.getSCEV(&*AI++));
+  A.push_back(SE.getSCEV(&*AI++));
+  A.push_back(SE.getSCEV(&*AI++));
+  A.push_back(SE.getSCEV(&*AI++));
+  const SCEV *A_rec = SE.getAddRecExpr(A, &L, SCEV::FlagAnyWrap);
+
+  SmallVector<const SCEV *, 5> B;
+  B.push_back(SE.getSCEV(&*AI++));
+  B.push_back(SE.getSCEV(&*AI++));
+  B.push_back(SE.getSCEV(&*AI++));
+  B.push_back(SE.getSCEV(&*AI++));
+  B.push_back(SE.getSCEV(&*AI++));
+  const SCEV *B_rec = SE.getAddRecExpr(B, &L, SCEV::FlagAnyWrap);
+
+  /* Spot check that we perform this transformation:
+     {A0,+,A1,+,A2,+,A3,+,A4} * {B0,+,B1,+,B2,+,B3,+,B4} =
+     {A0*B0,+,
+      A1*B0 + A0*B1 + A1*B1,+,
+      A2*B0 + 2A1*B1 + A0*B2 + 2A2*B1 + 2A1*B2 + A2*B2,+,
+      A3*B0 + 3A2*B1 + 3A1*B2 + A0*B3 + 3A3*B1 + 6A2*B2 + 3A1*B3 + 3A3*B2 +
+        3A2*B3 + A3*B3,+,
+      A4*B0 + 4A3*B1 + 6A2*B2 + 4A1*B3 + A0*B4 + 4A4*B1 + 12A3*B2 + 12A2*B3 +
+        4A1*B4 + 6A4*B2 + 12A3*B3 + 6A2*B4 + 4A4*B3 + 4A3*B4 + A4*B4,+,
+      5A4*B1 + 10A3*B2 + 10A2*B3 + 5A1*B4 + 20A4*B2 + 30A3*B3 + 20A2*B4 +
+        30A4*B3 + 30A3*B4 + 20A4*B4,+,
+      15A4*B2 + 20A3*B3 + 15A2*B4 + 60A4*B3 + 60A3*B4 + 90A4*B4,+,
+      35A4*B3 + 35A3*B4 + 140A4*B4,+,
+      70A4*B4}
+  */
+
+  const SCEVAddRecExpr *Product =
+      dyn_cast<SCEVAddRecExpr>(SE.getMulExpr(A_rec, B_rec));
+  ASSERT_TRUE(Product);
+  ASSERT_EQ(Product->getNumOperands(), 9u);
+
+  SmallVector<const SCEV *, 16> Sum;
+  Sum.push_back(SE.getMulExpr(A[0], B[0]));
+  EXPECT_EQ(Product->getOperand(0), SE.getAddExpr(Sum));
+  Sum.clear();
+
+  // SCEV produces different an equal but different expression for these.
+  // Re-enable when PR11052 is fixed.
+#if 0
+  Sum.push_back(SE.getMulExpr(A[1], B[0]));
+  Sum.push_back(SE.getMulExpr(A[0], B[1]));
+  Sum.push_back(SE.getMulExpr(A[1], B[1]));
+  EXPECT_EQ(Product->getOperand(1), SE.getAddExpr(Sum));
+  Sum.clear();
+
+  Sum.push_back(SE.getMulExpr(A[2], B[0]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 2), A[1], B[1]));
+  Sum.push_back(SE.getMulExpr(A[0], B[2]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 2), A[2], B[1]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 2), A[1], B[2]));
+  Sum.push_back(SE.getMulExpr(A[2], B[2]));
+  EXPECT_EQ(Product->getOperand(2), SE.getAddExpr(Sum));
+  Sum.clear();
+
+  Sum.push_back(SE.getMulExpr(A[3], B[0]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 3), A[2], B[1]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 3), A[1], B[2]));
+  Sum.push_back(SE.getMulExpr(A[0], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 3), A[3], B[1]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 6), A[2], B[2]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 3), A[1], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 3), A[3], B[2]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 3), A[2], B[3]));
+  Sum.push_back(SE.getMulExpr(A[3], B[3]));
+  EXPECT_EQ(Product->getOperand(3), SE.getAddExpr(Sum));
+  Sum.clear();
+
+  Sum.push_back(SE.getMulExpr(A[4], B[0]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 4), A[3], B[1]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 6), A[2], B[2]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 4), A[1], B[3]));
+  Sum.push_back(SE.getMulExpr(A[0], B[4]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 4), A[4], B[1]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 12), A[3], B[2]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 12), A[2], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 4), A[1], B[4]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 6), A[4], B[2]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 12), A[3], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 6), A[2], B[4]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 4), A[4], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 4), A[3], B[4]));
+  Sum.push_back(SE.getMulExpr(A[4], B[4]));
+  EXPECT_EQ(Product->getOperand(4), SE.getAddExpr(Sum));
+  Sum.clear();
+
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 5), A[4], B[1]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 10), A[3], B[2]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 10), A[2], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 5), A[1], B[4]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 20), A[4], B[2]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 30), A[3], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 20), A[2], B[4]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 30), A[4], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 30), A[3], B[4]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 20), A[4], B[4]));
+  EXPECT_EQ(Product->getOperand(5), SE.getAddExpr(Sum));
+  Sum.clear();
+
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 15), A[4], B[2]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 20), A[3], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 15), A[2], B[4]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 60), A[4], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 60), A[3], B[4]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 90), A[4], B[4]));
+  EXPECT_EQ(Product->getOperand(6), SE.getAddExpr(Sum));
+  Sum.clear();
+
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 35), A[4], B[3]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 35), A[3], B[4]));
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 140), A[4], B[4]));
+  EXPECT_EQ(Product->getOperand(7), SE.getAddExpr(Sum));
+  Sum.clear();
+#endif
 
-  // Manually clean up, since we allocated new SCEV objects after the
-  // pass was finished.
-  SE.releaseMemory();
+  Sum.push_back(SE.getMulExpr(SE.getConstant(Ty, 70), A[4], B[4]));
+  EXPECT_EQ(Product->getOperand(8), SE.getAddExpr(Sum));
 }
 
 }  // end anonymous namespace