llvm/unittests/Analysis/TBAATest.cpp

   1 //===--- TBAATest.cpp - Mixed TBAA unit tests -----------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "llvm/Analysis/AliasAnalysisEvaluator.h"
  10 #include "llvm/Analysis/Passes.h"
  11 #include "llvm/IR/Constants.h"
  12 #include "llvm/IR/Instructions.h"
  13 #include "llvm/IR/LLVMContext.h"
  14 #include "llvm/IR/LegacyPassManager.h"
  15 #include "llvm/IR/MDBuilder.h"
  16 #include "llvm/IR/Module.h"
  17 #include "llvm/IR/Verifier.h"
  18 #include "llvm/Support/CommandLine.h"
  19 #include "gtest/gtest.h"
  20
  21 namespace llvm {
  22 namespace {
  23
  24 class TBAATest : public testing::Test {
  25 protected:
  26   TBAATest() : M("TBAATest", C), MD(C) {}
  27
  28   LLVMContext C;
  29   Module M;
  30   MDBuilder MD;
  31 };
  32
  33 static StoreInst *getFunctionWithSingleStore(Module *M, StringRef Name) {
  34   auto &C = M->getContext();
  35   FunctionType *FTy = FunctionType::get(Type::getVoidTy(C), {});
  36   auto *F = Function::Create(FTy, Function::ExternalLinkage, Name, M);
  37   auto *BB = BasicBlock::Create(C, "entry", F);
  38   auto *IntType = Type::getInt32Ty(C);
  39   auto *PtrType = Type::getInt32PtrTy(C);
  40   auto *SI = new StoreInst(ConstantInt::get(IntType, 42),
  41                            ConstantPointerNull::get(PtrType), BB);
  42   ReturnInst::Create(C, nullptr, BB);
  43
  44   return SI;
  45 }
  46
  47 TEST_F(TBAATest, checkVerifierBehaviorForOldTBAA) {
  48   auto *SI = getFunctionWithSingleStore(&M, "f1");
  49   auto *F = SI->getFunction();
  50
  51   // C++ unit test case to avoid going through the auto upgrade logic.
  52   auto *RootMD = MD.createTBAARoot("Simple C/C++ TBAA");
  53   auto *MD1 = MD.createTBAANode("omnipotent char", RootMD);
  54   auto *MD2 = MD.createTBAANode("int", MD1);
  55   SI->setMetadata(LLVMContext::MD_tbaa, MD2);
  56
  57   SmallVector<char, 0> ErrorMsg;
  58   raw_svector_ostream Outs(ErrorMsg);
  59
  60   StringRef ExpectedFailureMsg(
  61       "Old-style TBAA is no longer allowed, use struct-path TBAA instead");
  62
  63   EXPECT_TRUE(verifyFunction(*F, &Outs));
  64   EXPECT_TRUE(StringRef(ErrorMsg.begin(), ErrorMsg.size())
  65                   .startswith(ExpectedFailureMsg));
  66 }
  67
  68 TEST_F(TBAATest, checkTBAAMerging) {
  69   auto *SI = getFunctionWithSingleStore(&M, "f2");
  70   auto *F = SI->getFunction();
  71
  72   auto *RootMD = MD.createTBAARoot("tbaa-root");
  73   auto *MD1 = MD.createTBAANode("scalar-a", RootMD);
  74   auto *StructTag1 = MD.createTBAAStructTagNode(MD1, MD1, 0);
  75   auto *MD2 = MD.createTBAANode("scalar-b", RootMD);
  76   auto *StructTag2 = MD.createTBAAStructTagNode(MD2, MD2, 0);
  77
  78   auto *GenericMD = MDNode::getMostGenericTBAA(StructTag1, StructTag2);
  79
  80   EXPECT_EQ(GenericMD, nullptr);
  81
  82   // Despite GenericMD being nullptr, we expect the setMetadata call to be well
  83   // defined and produce a well-formed function.
  84   SI->setMetadata(LLVMContext::MD_tbaa, GenericMD);
  85
  86   EXPECT_TRUE(!verifyFunction(*F));
  87 }
  88
  89 } // end anonymous namspace
  90 } // end llvm namespace