llvm/unittests/IR/DominatorTreeTest.cpp
Diego Novillo 97add46aee Fix dominator descendants for unreachable blocks.
When a block is unreachable, asking its dom tree descendants should
return the empty set. However, the computation of the descendants
was causing a segmentation fault because the dom tree node we get
from the basic block is initially NULL.

Fixed by adding a test for a valid dom tree node before we iterate.

The patch also adds some unit tests to the existing dom tree tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196099 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-02 14:08:27 +00:00

232 lines
7.7 KiB
C++

//===- 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/Analysis/Dominators.h"
#include "llvm/Analysis/PostDominators.h"
#include "llvm/Assembly/Parser.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/PassManager.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;
virtual bool runOnFunction(Function &F) {
DominatorTree *DT = &getAnalysis<DominatorTree>();
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);
return false;
}
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<DominatorTree>();
AU.addRequired<PostDominatorTree>();
}
DPass() : FunctionPass(ID) {
initializeDPassPass(*PassRegistry::getPassRegistry());
}
};
char DPass::ID = 0;
Module* makeLLVMModule(DPass *P) {
const char *ModuleStrig =
"declare i32 @g()\n" \
"define void @f(i32 %x) {\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 personality i32 ()* @g\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, NULL, Err, C);
}
TEST(DominatorTree, Unreachable) {
DPass *P = new DPass();
OwningPtr<Module> M(makeLLVMModule(P));
PassManager Passes;
Passes.add(P);
Passes.run(*M);
}
}
}
INITIALIZE_PASS_BEGIN(DPass, "dpass", "dpass", false, false)
INITIALIZE_PASS_DEPENDENCY(DominatorTree)
INITIALIZE_PASS_DEPENDENCY(PostDominatorTree)
INITIALIZE_PASS_END(DPass, "dpass", "dpass", false, false)