unittests/IR/DominatorTreeTest.cpp

   1 //===- llvm/unittests/IR/DominatorTreeTest.cpp - Constants unit tests -----===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "llvm/Analysis/Dominators.h"
  11 #include "llvm/Analysis/PostDominators.h"
  12 #include "llvm/Assembly/Parser.h"
  13 #include "llvm/IR/Instructions.h"
  14 #include "llvm/IR/LLVMContext.h"
  15 #include "llvm/IR/Module.h"
  16 #include "llvm/PassManager.h"
  17 #include "llvm/Support/SourceMgr.h"
  18 #include "gtest/gtest.h"
  19
  20 using namespace llvm;
  21
  22 namespace llvm {
  23   void initializeDPassPass(PassRegistry&);
  24
  25   namespace {
  26     struct DPass : public FunctionPass {
  27       static char ID;
  28       virtual bool runOnFunction(Function &F) {
  29         DominatorTree *DT = &getAnalysis<DominatorTree>();
  30         PostDominatorTree *PDT = &getAnalysis<PostDominatorTree>();
  31         Function::iterator FI = F.begin();
  32
  33         BasicBlock *BB0 = FI++;
  34         BasicBlock::iterator BBI = BB0->begin();
  35         Instruction *Y1 = BBI++;
  36         Instruction *Y2 = BBI++;
  37         Instruction *Y3 = BBI++;
  38
  39         BasicBlock *BB1 = FI++;
  40         BBI = BB1->begin();
  41         Instruction *Y4 = BBI++;
  42
  43         BasicBlock *BB2 = FI++;
  44         BBI = BB2->begin();
  45         Instruction *Y5 = BBI++;
  46
  47         BasicBlock *BB3 = FI++;
  48         BBI = BB3->begin();
  49         Instruction *Y6 = BBI++;
  50         Instruction *Y7 = BBI++;
  51
  52         BasicBlock *BB4 = FI++;
  53         BBI = BB4->begin();
  54         Instruction *Y8 = BBI++;
  55         Instruction *Y9 = BBI++;
  56
  57         // Reachability
  58         EXPECT_TRUE(DT->isReachableFromEntry(BB0));
  59         EXPECT_TRUE(DT->isReachableFromEntry(BB1));
  60         EXPECT_TRUE(DT->isReachableFromEntry(BB2));
  61         EXPECT_FALSE(DT->isReachableFromEntry(BB3));
  62         EXPECT_TRUE(DT->isReachableFromEntry(BB4));
  63
  64         // BB dominance
  65         EXPECT_TRUE(DT->dominates(BB0, BB0));
  66         EXPECT_TRUE(DT->dominates(BB0, BB1));
  67         EXPECT_TRUE(DT->dominates(BB0, BB2));
  68         EXPECT_TRUE(DT->dominates(BB0, BB3));
  69         EXPECT_TRUE(DT->dominates(BB0, BB4));
  70
  71         EXPECT_FALSE(DT->dominates(BB1, BB0));
  72         EXPECT_TRUE(DT->dominates(BB1, BB1));
  73         EXPECT_FALSE(DT->dominates(BB1, BB2));
  74         EXPECT_TRUE(DT->dominates(BB1, BB3));
  75         EXPECT_FALSE(DT->dominates(BB1, BB4));
  76
  77         EXPECT_FALSE(DT->dominates(BB2, BB0));
  78         EXPECT_FALSE(DT->dominates(BB2, BB1));
  79         EXPECT_TRUE(DT->dominates(BB2, BB2));
  80         EXPECT_TRUE(DT->dominates(BB2, BB3));
  81         EXPECT_FALSE(DT->dominates(BB2, BB4));
  82
  83         EXPECT_FALSE(DT->dominates(BB3, BB0));
  84         EXPECT_FALSE(DT->dominates(BB3, BB1));
  85         EXPECT_FALSE(DT->dominates(BB3, BB2));
  86         EXPECT_TRUE(DT->dominates(BB3, BB3));
  87         EXPECT_FALSE(DT->dominates(BB3, BB4));
  88
  89         // BB proper dominance
  90         EXPECT_FALSE(DT->properlyDominates(BB0, BB0));
  91         EXPECT_TRUE(DT->properlyDominates(BB0, BB1));
  92         EXPECT_TRUE(DT->properlyDominates(BB0, BB2));
  93         EXPECT_TRUE(DT->properlyDominates(BB0, BB3));
  94
  95         EXPECT_FALSE(DT->properlyDominates(BB1, BB0));
  96         EXPECT_FALSE(DT->properlyDominates(BB1, BB1));
  97         EXPECT_FALSE(DT->properlyDominates(BB1, BB2));
  98         EXPECT_TRUE(DT->properlyDominates(BB1, BB3));
  99
 100         EXPECT_FALSE(DT->properlyDominates(BB2, BB0));
 101         EXPECT_FALSE(DT->properlyDominates(BB2, BB1));
 102         EXPECT_FALSE(DT->properlyDominates(BB2, BB2));
 103         EXPECT_TRUE(DT->properlyDominates(BB2, BB3));
 104
 105         EXPECT_FALSE(DT->properlyDominates(BB3, BB0));
 106         EXPECT_FALSE(DT->properlyDominates(BB3, BB1));
 107         EXPECT_FALSE(DT->properlyDominates(BB3, BB2));
 108         EXPECT_FALSE(DT->properlyDominates(BB3, BB3));
 109
 110         // Instruction dominance in the same reachable BB
 111         EXPECT_FALSE(DT->dominates(Y1, Y1));
 112         EXPECT_TRUE(DT->dominates(Y1, Y2));
 113         EXPECT_FALSE(DT->dominates(Y2, Y1));
 114         EXPECT_FALSE(DT->dominates(Y2, Y2));
 115
 116         // Instruction dominance in the same unreachable BB
 117         EXPECT_TRUE(DT->dominates(Y6, Y6));
 118         EXPECT_TRUE(DT->dominates(Y6, Y7));
 119         EXPECT_TRUE(DT->dominates(Y7, Y6));
 120         EXPECT_TRUE(DT->dominates(Y7, Y7));
 121
 122         // Invoke
 123         EXPECT_TRUE(DT->dominates(Y3, Y4));
 124         EXPECT_FALSE(DT->dominates(Y3, Y5));
 125
 126         // Phi
 127         EXPECT_TRUE(DT->dominates(Y2, Y9));
 128         EXPECT_FALSE(DT->dominates(Y3, Y9));
 129         EXPECT_FALSE(DT->dominates(Y8, Y9));
 130
 131         // Anything dominates unreachable
 132         EXPECT_TRUE(DT->dominates(Y1, Y6));
 133         EXPECT_TRUE(DT->dominates(Y3, Y6));
 134
 135         // Unreachable doesn't dominate reachable
 136         EXPECT_FALSE(DT->dominates(Y6, Y1));
 137
 138         // Instruction, BB dominance
 139         EXPECT_FALSE(DT->dominates(Y1, BB0));
 140         EXPECT_TRUE(DT->dominates(Y1, BB1));
 141         EXPECT_TRUE(DT->dominates(Y1, BB2));
 142         EXPECT_TRUE(DT->dominates(Y1, BB3));
 143         EXPECT_TRUE(DT->dominates(Y1, BB4));
 144
 145         EXPECT_FALSE(DT->dominates(Y3, BB0));
 146         EXPECT_TRUE(DT->dominates(Y3, BB1));
 147         EXPECT_FALSE(DT->dominates(Y3, BB2));
 148         EXPECT_TRUE(DT->dominates(Y3, BB3));
 149         EXPECT_FALSE(DT->dominates(Y3, BB4));
 150
 151         EXPECT_TRUE(DT->dominates(Y6, BB3));
 152
 153         // Post dominance.
 154         EXPECT_TRUE(PDT->dominates(BB0, BB0));
 155         EXPECT_FALSE(PDT->dominates(BB1, BB0));
 156         EXPECT_FALSE(PDT->dominates(BB2, BB0));
 157         EXPECT_FALSE(PDT->dominates(BB3, BB0));
 158         EXPECT_TRUE(PDT->dominates(BB4, BB1));
 159
 160         // Dominance descendants.
 161         SmallVector<BasicBlock *, 8> DominatedBBs, PostDominatedBBs;
 162
 163         DT->getDescendants(BB0, DominatedBBs);
 164         PDT->getDescendants(BB0, PostDominatedBBs);
 165         EXPECT_EQ(DominatedBBs.size(), 4UL);
 166         EXPECT_EQ(PostDominatedBBs.size(), 1UL);
 167
 168         // BB3 is unreachable. It should have no dominators nor postdominators.
 169         DominatedBBs.clear();
 170         PostDominatedBBs.clear();
 171         DT->getDescendants(BB3, DominatedBBs);
 172         DT->getDescendants(BB3, PostDominatedBBs);
 173         EXPECT_EQ(DominatedBBs.size(), 0UL);
 174         EXPECT_EQ(PostDominatedBBs.size(), 0UL);
 175
 176         return false;
 177       }
 178       virtual void getAnalysisUsage(AnalysisUsage &AU) const {
 179         AU.addRequired<DominatorTree>();
 180         AU.addRequired<PostDominatorTree>();
 181       }
 182       DPass() : FunctionPass(ID) {
 183         initializeDPassPass(*PassRegistry::getPassRegistry());
 184       }
 185     };
 186     char DPass::ID = 0;
 187
 188
 189     Module* makeLLVMModule(DPass *P) {
 190       const char *ModuleStrig =
 191         "declare i32 @g()\n" \
 192         "define void @f(i32 %x) {\n" \
 193         "bb0:\n" \
 194         "  %y1 = add i32 %x, 1\n" \
 195         "  %y2 = add i32 %x, 1\n" \
 196         "  %y3 = invoke i32 @g() to label %bb1 unwind label %bb2\n" \
 197         "bb1:\n" \
 198         "  %y4 = add i32 %x, 1\n" \
 199         "  br label %bb4\n" \
 200         "bb2:\n" \
 201         "  %y5 = landingpad i32 personality i32 ()* @g\n" \
 202         "          cleanup\n" \
 203         "  br label %bb4\n" \
 204         "bb3:\n" \
 205         "  %y6 = add i32 %x, 1\n" \
 206         "  %y7 = add i32 %x, 1\n" \
 207         "  ret void\n" \
 208         "bb4:\n" \
 209         "  %y8 = phi i32 [0, %bb2], [%y4, %bb1]\n"
 210         "  %y9 = phi i32 [0, %bb2], [%y4, %bb1]\n"
 211         "  ret void\n" \
 212         "}\n";
 213       LLVMContext &C = getGlobalContext();
 214       SMDiagnostic Err;
 215       return ParseAssemblyString(ModuleStrig, NULL, Err, C);
 216     }
 217
 218     TEST(DominatorTree, Unreachable) {
 219       DPass *P = new DPass();
 220       OwningPtr<Module> M(makeLLVMModule(P));
 221       PassManager Passes;
 222       Passes.add(P);
 223       Passes.run(*M);
 224     }
 225   }
 226 }
 227
 228 INITIALIZE_PASS_BEGIN(DPass, "dpass", "dpass", false, false)
 229 INITIALIZE_PASS_DEPENDENCY(DominatorTree)
 230 INITIALIZE_PASS_DEPENDENCY(PostDominatorTree)
 231 INITIALIZE_PASS_END(DPass, "dpass", "dpass", false, false)