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//===- llvm/unittests/IR/DominatorTreeTest.cpp - Constants 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/IR/Dominators.h"
#include "llvm/Analysis/PostDominators.h"
#include "llvm/AsmParser/Parser.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/Support/SourceMgr.h"
#include "gtest/gtest.h"
using namespace llvm;
namespace llvm {
void initializeDPassPass(PassRegistry&);
namespace {
struct DPass : public FunctionPass {
static char ID;
bool runOnFunction(Function &F) override {
DominatorTree *DT =
&getAnalysis<DominatorTreeWrapperPass>().getDomTree();
PostDominatorTree *PDT = &getAnalysis<PostDominatorTree>();
Function::iterator FI = F.begin();
BasicBlock *BB0 = &*FI++;
BasicBlock::iterator BBI = BB0->begin();
Instruction *Y1 = &*BBI++;
Instruction *Y2 = &*BBI++;
Instruction *Y3 = &*BBI++;
BasicBlock *BB1 = &*FI++;
BBI = BB1->begin();
Instruction *Y4 = &*BBI++;
BasicBlock *BB2 = &*FI++;
BBI = BB2->begin();
Instruction *Y5 = &*BBI++;
BasicBlock *BB3 = &*FI++;
BBI = BB3->begin();
Instruction *Y6 = &*BBI++;
Instruction *Y7 = &*BBI++;
BasicBlock *BB4 = &*FI++;
BBI = BB4->begin();
Instruction *Y8 = &*BBI++;
Instruction *Y9 = &*BBI++;
// Reachability
EXPECT_TRUE(DT->isReachableFromEntry(BB0));
EXPECT_TRUE(DT->isReachableFromEntry(BB1));
EXPECT_TRUE(DT->isReachableFromEntry(BB2));
EXPECT_FALSE(DT->isReachableFromEntry(BB3));
EXPECT_TRUE(DT->isReachableFromEntry(BB4));
// BB dominance
EXPECT_TRUE(DT->dominates(BB0, BB0));
EXPECT_TRUE(DT->dominates(BB0, BB1));
EXPECT_TRUE(DT->dominates(BB0, BB2));
EXPECT_TRUE(DT->dominates(BB0, BB3));
EXPECT_TRUE(DT->dominates(BB0, BB4));
EXPECT_FALSE(DT->dominates(BB1, BB0));
EXPECT_TRUE(DT->dominates(BB1, BB1));
EXPECT_FALSE(DT->dominates(BB1, BB2));
EXPECT_TRUE(DT->dominates(BB1, BB3));
EXPECT_FALSE(DT->dominates(BB1, BB4));
EXPECT_FALSE(DT->dominates(BB2, BB0));
EXPECT_FALSE(DT->dominates(BB2, BB1));
EXPECT_TRUE(DT->dominates(BB2, BB2));
EXPECT_TRUE(DT->dominates(BB2, BB3));
EXPECT_FALSE(DT->dominates(BB2, BB4));
EXPECT_FALSE(DT->dominates(BB3, BB0));
EXPECT_FALSE(DT->dominates(BB3, BB1));
EXPECT_FALSE(DT->dominates(BB3, BB2));
EXPECT_TRUE(DT->dominates(BB3, BB3));
EXPECT_FALSE(DT->dominates(BB3, BB4));
// BB proper dominance
EXPECT_FALSE(DT->properlyDominates(BB0, BB0));
EXPECT_TRUE(DT->properlyDominates(BB0, BB1));
EXPECT_TRUE(DT->properlyDominates(BB0, BB2));
EXPECT_TRUE(DT->properlyDominates(BB0, BB3));
EXPECT_FALSE(DT->properlyDominates(BB1, BB0));
EXPECT_FALSE(DT->properlyDominates(BB1, BB1));
EXPECT_FALSE(DT->properlyDominates(BB1, BB2));
EXPECT_TRUE(DT->properlyDominates(BB1, BB3));
EXPECT_FALSE(DT->properlyDominates(BB2, BB0));
EXPECT_FALSE(DT->properlyDominates(BB2, BB1));
EXPECT_FALSE(DT->properlyDominates(BB2, BB2));
EXPECT_TRUE(DT->properlyDominates(BB2, BB3));
EXPECT_FALSE(DT->properlyDominates(BB3, BB0));
EXPECT_FALSE(DT->properlyDominates(BB3, BB1));
EXPECT_FALSE(DT->properlyDominates(BB3, BB2));
EXPECT_FALSE(DT->properlyDominates(BB3, BB3));
// Instruction dominance in the same reachable BB
EXPECT_FALSE(DT->dominates(Y1, Y1));
EXPECT_TRUE(DT->dominates(Y1, Y2));
EXPECT_FALSE(DT->dominates(Y2, Y1));
EXPECT_FALSE(DT->dominates(Y2, Y2));
// Instruction dominance in the same unreachable BB
EXPECT_TRUE(DT->dominates(Y6, Y6));
EXPECT_TRUE(DT->dominates(Y6, Y7));
EXPECT_TRUE(DT->dominates(Y7, Y6));
EXPECT_TRUE(DT->dominates(Y7, Y7));
// Invoke
EXPECT_TRUE(DT->dominates(Y3, Y4));
EXPECT_FALSE(DT->dominates(Y3, Y5));
// Phi
EXPECT_TRUE(DT->dominates(Y2, Y9));
EXPECT_FALSE(DT->dominates(Y3, Y9));
EXPECT_FALSE(DT->dominates(Y8, Y9));
// Anything dominates unreachable
EXPECT_TRUE(DT->dominates(Y1, Y6));
EXPECT_TRUE(DT->dominates(Y3, Y6));
// Unreachable doesn't dominate reachable
EXPECT_FALSE(DT->dominates(Y6, Y1));
// Instruction, BB dominance
EXPECT_FALSE(DT->dominates(Y1, BB0));
EXPECT_TRUE(DT->dominates(Y1, BB1));
EXPECT_TRUE(DT->dominates(Y1, BB2));
EXPECT_TRUE(DT->dominates(Y1, BB3));
EXPECT_TRUE(DT->dominates(Y1, BB4));
EXPECT_FALSE(DT->dominates(Y3, BB0));
EXPECT_TRUE(DT->dominates(Y3, BB1));
EXPECT_FALSE(DT->dominates(Y3, BB2));
EXPECT_TRUE(DT->dominates(Y3, BB3));
EXPECT_FALSE(DT->dominates(Y3, BB4));
EXPECT_TRUE(DT->dominates(Y6, BB3));
// Post dominance.
EXPECT_TRUE(PDT->dominates(BB0, BB0));
EXPECT_FALSE(PDT->dominates(BB1, BB0));
EXPECT_FALSE(PDT->dominates(BB2, BB0));
EXPECT_FALSE(PDT->dominates(BB3, BB0));
EXPECT_TRUE(PDT->dominates(BB4, BB1));
// Dominance descendants.
SmallVector<BasicBlock *, 8> DominatedBBs, PostDominatedBBs;
DT->getDescendants(BB0, DominatedBBs);
PDT->getDescendants(BB0, PostDominatedBBs);
EXPECT_EQ(DominatedBBs.size(), 4UL);
EXPECT_EQ(PostDominatedBBs.size(), 1UL);
// BB3 is unreachable. It should have no dominators nor postdominators.
DominatedBBs.clear();
PostDominatedBBs.clear();
DT->getDescendants(BB3, DominatedBBs);
DT->getDescendants(BB3, PostDominatedBBs);
EXPECT_EQ(DominatedBBs.size(), 0UL);
EXPECT_EQ(PostDominatedBBs.size(), 0UL);
// Check DFS Numbers before
EXPECT_EQ(DT->getNode(BB0)->getDFSNumIn(), 0UL);
EXPECT_EQ(DT->getNode(BB0)->getDFSNumOut(), 7UL);
EXPECT_EQ(DT->getNode(BB1)->getDFSNumIn(), 1UL);
EXPECT_EQ(DT->getNode(BB1)->getDFSNumOut(), 2UL);
EXPECT_EQ(DT->getNode(BB2)->getDFSNumIn(), 5UL);
EXPECT_EQ(DT->getNode(BB2)->getDFSNumOut(), 6UL);
EXPECT_EQ(DT->getNode(BB4)->getDFSNumIn(), 3UL);
EXPECT_EQ(DT->getNode(BB4)->getDFSNumOut(), 4UL);
// Reattach block 3 to block 1 and recalculate
BB1->getTerminator()->eraseFromParent();
BranchInst::Create(BB4, BB3, ConstantInt::getTrue(F.getContext()), BB1);
DT->recalculate(F);
// Check DFS Numbers after
EXPECT_EQ(DT->getNode(BB0)->getDFSNumIn(), 0UL);
EXPECT_EQ(DT->getNode(BB0)->getDFSNumOut(), 9UL);
EXPECT_EQ(DT->getNode(BB1)->getDFSNumIn(), 1UL);
EXPECT_EQ(DT->getNode(BB1)->getDFSNumOut(), 4UL);
EXPECT_EQ(DT->getNode(BB2)->getDFSNumIn(), 7UL);
EXPECT_EQ(DT->getNode(BB2)->getDFSNumOut(), 8UL);
EXPECT_EQ(DT->getNode(BB3)->getDFSNumIn(), 2UL);
EXPECT_EQ(DT->getNode(BB3)->getDFSNumOut(), 3UL);
EXPECT_EQ(DT->getNode(BB4)->getDFSNumIn(), 5UL);
EXPECT_EQ(DT->getNode(BB4)->getDFSNumOut(), 6UL);
return false;
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<DominatorTreeWrapperPass>();
AU.addRequired<PostDominatorTree>();
}
DPass() : FunctionPass(ID) {
initializeDPassPass(*PassRegistry::getPassRegistry());
}
};
char DPass::ID = 0;
std::unique_ptr<Module> makeLLVMModule(DPass *P) {
const char *ModuleStrig =
"declare i32 @g()\n" \
"define void @f(i32 %x) personality i32 ()* @g {\n" \
"bb0:\n" \
" %y1 = add i32 %x, 1\n" \
" %y2 = add i32 %x, 1\n" \
" %y3 = invoke i32 @g() to label %bb1 unwind label %bb2\n" \
"bb1:\n" \
" %y4 = add i32 %x, 1\n" \
" br label %bb4\n" \
"bb2:\n" \
" %y5 = landingpad i32\n" \
" cleanup\n" \
" br label %bb4\n" \
"bb3:\n" \
" %y6 = add i32 %x, 1\n" \
" %y7 = add i32 %x, 1\n" \
" ret void\n" \
"bb4:\n" \
" %y8 = phi i32 [0, %bb2], [%y4, %bb1]\n"
" %y9 = phi i32 [0, %bb2], [%y4, %bb1]\n"
" ret void\n" \
"}\n";
LLVMContext &C = getGlobalContext();
SMDiagnostic Err;
return parseAssemblyString(ModuleStrig, Err, C);
}
TEST(DominatorTree, Unreachable) {
DPass *P = new DPass();
std::unique_ptr<Module> M = makeLLVMModule(P);
legacy::PassManager Passes;
Passes.add(P);
Passes.run(*M);
}
}
}
INITIALIZE_PASS_BEGIN(DPass, "dpass", "dpass", false, false)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(PostDominatorTree)
INITIALIZE_PASS_END(DPass, "dpass", "dpass", false, false)
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