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d869913f3b
Summary: This patch makes LoopDeletion use the incremental DominatorTree API. We modify LoopDeletion to perform the deletion in 5 steps: 1. Create a new dummy edge from the preheader to the exit, by adding a conditional branch. 2. Inform the DomTree about the new edge. 3. Remove the conditional branch and replace it with an unconditional edge to the exit. This removes the edge to the loop header, making it unreachable. 4. Inform the DomTree about the deleted edge. 5. Remove the unreachable block from the function. Creating the dummy conditional branch is necessary to perform incremental DomTree update. We should consider using the batch updater when it's ready. Reviewers: dberlin, davide, grosser, sanjoy Reviewed By: dberlin, grosser Subscribers: mzolotukhin, llvm-commits Differential Revision: https://reviews.llvm.org/D35391 llvm-svn: 309850
903 lines
30 KiB
C++
903 lines
30 KiB
C++
//===- llvm/unittests/IR/DominatorTreeTest.cpp - Constants unit tests -----===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include <random>
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#include "llvm/Analysis/PostDominators.h"
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#include "llvm/AsmParser/Parser.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/Dominators.h"
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#include "llvm/IR/Instructions.h"
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#include "llvm/IR/LLVMContext.h"
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#include "llvm/IR/Module.h"
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#include "llvm/Support/SourceMgr.h"
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#include "CFGBuilder.h"
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#include "gtest/gtest.h"
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using namespace llvm;
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struct PostDomTree : PostDomTreeBase<BasicBlock> {
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PostDomTree(Function &F) { recalculate(F); }
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};
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/// Build the dominator tree for the function and run the Test.
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static void runWithDomTree(
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Module &M, StringRef FuncName,
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function_ref<void(Function &F, DominatorTree *DT, PostDomTree *PDT)> Test) {
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auto *F = M.getFunction(FuncName);
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ASSERT_NE(F, nullptr) << "Could not find " << FuncName;
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// Compute the dominator tree for the function.
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DominatorTree DT(*F);
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PostDomTree PDT(*F);
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Test(*F, &DT, &PDT);
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}
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static std::unique_ptr<Module> makeLLVMModule(LLVMContext &Context,
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StringRef ModuleStr) {
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SMDiagnostic Err;
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std::unique_ptr<Module> M = parseAssemblyString(ModuleStr, Err, Context);
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assert(M && "Bad assembly?");
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return M;
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}
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TEST(DominatorTree, Unreachable) {
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StringRef ModuleString =
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"declare i32 @g()\n"
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"define void @f(i32 %x) personality i32 ()* @g {\n"
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"bb0:\n"
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" %y1 = add i32 %x, 1\n"
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" %y2 = add i32 %x, 1\n"
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" %y3 = invoke i32 @g() to label %bb1 unwind label %bb2\n"
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"bb1:\n"
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" %y4 = add i32 %x, 1\n"
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" br label %bb4\n"
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"bb2:\n"
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" %y5 = landingpad i32\n"
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" cleanup\n"
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" br label %bb4\n"
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"bb3:\n"
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" %y6 = add i32 %x, 1\n"
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" %y7 = add i32 %x, 1\n"
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" ret void\n"
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"bb4:\n"
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" %y8 = phi i32 [0, %bb2], [%y4, %bb1]\n"
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" %y9 = phi i32 [0, %bb2], [%y4, %bb1]\n"
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" ret void\n"
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"}\n";
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// Parse the module.
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LLVMContext Context;
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std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleString);
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runWithDomTree(
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*M, "f", [&](Function &F, DominatorTree *DT, PostDomTree *PDT) {
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Function::iterator FI = F.begin();
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BasicBlock *BB0 = &*FI++;
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BasicBlock::iterator BBI = BB0->begin();
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Instruction *Y1 = &*BBI++;
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Instruction *Y2 = &*BBI++;
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Instruction *Y3 = &*BBI++;
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BasicBlock *BB1 = &*FI++;
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BBI = BB1->begin();
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Instruction *Y4 = &*BBI++;
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BasicBlock *BB2 = &*FI++;
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BBI = BB2->begin();
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Instruction *Y5 = &*BBI++;
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BasicBlock *BB3 = &*FI++;
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BBI = BB3->begin();
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Instruction *Y6 = &*BBI++;
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Instruction *Y7 = &*BBI++;
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BasicBlock *BB4 = &*FI++;
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BBI = BB4->begin();
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Instruction *Y8 = &*BBI++;
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Instruction *Y9 = &*BBI++;
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// Reachability
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EXPECT_TRUE(DT->isReachableFromEntry(BB0));
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EXPECT_TRUE(DT->isReachableFromEntry(BB1));
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EXPECT_TRUE(DT->isReachableFromEntry(BB2));
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EXPECT_FALSE(DT->isReachableFromEntry(BB3));
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EXPECT_TRUE(DT->isReachableFromEntry(BB4));
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// BB dominance
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EXPECT_TRUE(DT->dominates(BB0, BB0));
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EXPECT_TRUE(DT->dominates(BB0, BB1));
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EXPECT_TRUE(DT->dominates(BB0, BB2));
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EXPECT_TRUE(DT->dominates(BB0, BB3));
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EXPECT_TRUE(DT->dominates(BB0, BB4));
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EXPECT_FALSE(DT->dominates(BB1, BB0));
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EXPECT_TRUE(DT->dominates(BB1, BB1));
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EXPECT_FALSE(DT->dominates(BB1, BB2));
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EXPECT_TRUE(DT->dominates(BB1, BB3));
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EXPECT_FALSE(DT->dominates(BB1, BB4));
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EXPECT_FALSE(DT->dominates(BB2, BB0));
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EXPECT_FALSE(DT->dominates(BB2, BB1));
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EXPECT_TRUE(DT->dominates(BB2, BB2));
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EXPECT_TRUE(DT->dominates(BB2, BB3));
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EXPECT_FALSE(DT->dominates(BB2, BB4));
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EXPECT_FALSE(DT->dominates(BB3, BB0));
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EXPECT_FALSE(DT->dominates(BB3, BB1));
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EXPECT_FALSE(DT->dominates(BB3, BB2));
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EXPECT_TRUE(DT->dominates(BB3, BB3));
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EXPECT_FALSE(DT->dominates(BB3, BB4));
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// BB proper dominance
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EXPECT_FALSE(DT->properlyDominates(BB0, BB0));
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EXPECT_TRUE(DT->properlyDominates(BB0, BB1));
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EXPECT_TRUE(DT->properlyDominates(BB0, BB2));
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EXPECT_TRUE(DT->properlyDominates(BB0, BB3));
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EXPECT_FALSE(DT->properlyDominates(BB1, BB0));
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EXPECT_FALSE(DT->properlyDominates(BB1, BB1));
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EXPECT_FALSE(DT->properlyDominates(BB1, BB2));
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EXPECT_TRUE(DT->properlyDominates(BB1, BB3));
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EXPECT_FALSE(DT->properlyDominates(BB2, BB0));
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EXPECT_FALSE(DT->properlyDominates(BB2, BB1));
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EXPECT_FALSE(DT->properlyDominates(BB2, BB2));
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EXPECT_TRUE(DT->properlyDominates(BB2, BB3));
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EXPECT_FALSE(DT->properlyDominates(BB3, BB0));
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EXPECT_FALSE(DT->properlyDominates(BB3, BB1));
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EXPECT_FALSE(DT->properlyDominates(BB3, BB2));
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EXPECT_FALSE(DT->properlyDominates(BB3, BB3));
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// Instruction dominance in the same reachable BB
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EXPECT_FALSE(DT->dominates(Y1, Y1));
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EXPECT_TRUE(DT->dominates(Y1, Y2));
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EXPECT_FALSE(DT->dominates(Y2, Y1));
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EXPECT_FALSE(DT->dominates(Y2, Y2));
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// Instruction dominance in the same unreachable BB
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EXPECT_TRUE(DT->dominates(Y6, Y6));
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EXPECT_TRUE(DT->dominates(Y6, Y7));
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EXPECT_TRUE(DT->dominates(Y7, Y6));
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EXPECT_TRUE(DT->dominates(Y7, Y7));
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// Invoke
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EXPECT_TRUE(DT->dominates(Y3, Y4));
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EXPECT_FALSE(DT->dominates(Y3, Y5));
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// Phi
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EXPECT_TRUE(DT->dominates(Y2, Y9));
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EXPECT_FALSE(DT->dominates(Y3, Y9));
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EXPECT_FALSE(DT->dominates(Y8, Y9));
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// Anything dominates unreachable
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EXPECT_TRUE(DT->dominates(Y1, Y6));
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EXPECT_TRUE(DT->dominates(Y3, Y6));
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// Unreachable doesn't dominate reachable
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EXPECT_FALSE(DT->dominates(Y6, Y1));
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// Instruction, BB dominance
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EXPECT_FALSE(DT->dominates(Y1, BB0));
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EXPECT_TRUE(DT->dominates(Y1, BB1));
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EXPECT_TRUE(DT->dominates(Y1, BB2));
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EXPECT_TRUE(DT->dominates(Y1, BB3));
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EXPECT_TRUE(DT->dominates(Y1, BB4));
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EXPECT_FALSE(DT->dominates(Y3, BB0));
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EXPECT_TRUE(DT->dominates(Y3, BB1));
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EXPECT_FALSE(DT->dominates(Y3, BB2));
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EXPECT_TRUE(DT->dominates(Y3, BB3));
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EXPECT_FALSE(DT->dominates(Y3, BB4));
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EXPECT_TRUE(DT->dominates(Y6, BB3));
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// Post dominance.
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EXPECT_TRUE(PDT->dominates(BB0, BB0));
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EXPECT_FALSE(PDT->dominates(BB1, BB0));
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EXPECT_FALSE(PDT->dominates(BB2, BB0));
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EXPECT_FALSE(PDT->dominates(BB3, BB0));
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EXPECT_TRUE(PDT->dominates(BB4, BB1));
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// Dominance descendants.
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SmallVector<BasicBlock *, 8> DominatedBBs, PostDominatedBBs;
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DT->getDescendants(BB0, DominatedBBs);
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PDT->getDescendants(BB0, PostDominatedBBs);
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EXPECT_EQ(DominatedBBs.size(), 4UL);
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EXPECT_EQ(PostDominatedBBs.size(), 1UL);
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// BB3 is unreachable. It should have no dominators nor postdominators.
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DominatedBBs.clear();
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PostDominatedBBs.clear();
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DT->getDescendants(BB3, DominatedBBs);
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DT->getDescendants(BB3, PostDominatedBBs);
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EXPECT_EQ(DominatedBBs.size(), 0UL);
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EXPECT_EQ(PostDominatedBBs.size(), 0UL);
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// Check DFS Numbers before
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DT->updateDFSNumbers();
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EXPECT_EQ(DT->getNode(BB0)->getDFSNumIn(), 0UL);
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EXPECT_EQ(DT->getNode(BB0)->getDFSNumOut(), 7UL);
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EXPECT_EQ(DT->getNode(BB1)->getDFSNumIn(), 1UL);
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EXPECT_EQ(DT->getNode(BB1)->getDFSNumOut(), 2UL);
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EXPECT_EQ(DT->getNode(BB2)->getDFSNumIn(), 5UL);
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EXPECT_EQ(DT->getNode(BB2)->getDFSNumOut(), 6UL);
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EXPECT_EQ(DT->getNode(BB4)->getDFSNumIn(), 3UL);
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EXPECT_EQ(DT->getNode(BB4)->getDFSNumOut(), 4UL);
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// Check levels before
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EXPECT_EQ(DT->getNode(BB0)->getLevel(), 0U);
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EXPECT_EQ(DT->getNode(BB1)->getLevel(), 1U);
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EXPECT_EQ(DT->getNode(BB2)->getLevel(), 1U);
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EXPECT_EQ(DT->getNode(BB4)->getLevel(), 1U);
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// Reattach block 3 to block 1 and recalculate
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BB1->getTerminator()->eraseFromParent();
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BranchInst::Create(BB4, BB3, ConstantInt::getTrue(F.getContext()), BB1);
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DT->recalculate(F);
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// Check DFS Numbers after
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DT->updateDFSNumbers();
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EXPECT_EQ(DT->getNode(BB0)->getDFSNumIn(), 0UL);
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EXPECT_EQ(DT->getNode(BB0)->getDFSNumOut(), 9UL);
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EXPECT_EQ(DT->getNode(BB1)->getDFSNumIn(), 1UL);
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EXPECT_EQ(DT->getNode(BB1)->getDFSNumOut(), 4UL);
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EXPECT_EQ(DT->getNode(BB2)->getDFSNumIn(), 7UL);
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EXPECT_EQ(DT->getNode(BB2)->getDFSNumOut(), 8UL);
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EXPECT_EQ(DT->getNode(BB3)->getDFSNumIn(), 2UL);
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EXPECT_EQ(DT->getNode(BB3)->getDFSNumOut(), 3UL);
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EXPECT_EQ(DT->getNode(BB4)->getDFSNumIn(), 5UL);
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EXPECT_EQ(DT->getNode(BB4)->getDFSNumOut(), 6UL);
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// Check levels after
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EXPECT_EQ(DT->getNode(BB0)->getLevel(), 0U);
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EXPECT_EQ(DT->getNode(BB1)->getLevel(), 1U);
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EXPECT_EQ(DT->getNode(BB2)->getLevel(), 1U);
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EXPECT_EQ(DT->getNode(BB3)->getLevel(), 2U);
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EXPECT_EQ(DT->getNode(BB4)->getLevel(), 1U);
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// Change root node
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DT->verifyDomTree();
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BasicBlock *NewEntry =
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BasicBlock::Create(F.getContext(), "new_entry", &F, BB0);
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BranchInst::Create(BB0, NewEntry);
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EXPECT_EQ(F.begin()->getName(), NewEntry->getName());
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EXPECT_TRUE(&F.getEntryBlock() == NewEntry);
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DT->setNewRoot(NewEntry);
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DT->verifyDomTree();
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});
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}
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TEST(DominatorTree, NonUniqueEdges) {
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StringRef ModuleString =
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"define i32 @f(i32 %i, i32 *%p) {\n"
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"bb0:\n"
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" store i32 %i, i32 *%p\n"
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" switch i32 %i, label %bb2 [\n"
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" i32 0, label %bb1\n"
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" i32 1, label %bb1\n"
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" ]\n"
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" bb1:\n"
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" ret i32 1\n"
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" bb2:\n"
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" ret i32 4\n"
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"}\n";
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// Parse the module.
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LLVMContext Context;
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std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleString);
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runWithDomTree(
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*M, "f", [&](Function &F, DominatorTree *DT, PostDomTree *PDT) {
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Function::iterator FI = F.begin();
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BasicBlock *BB0 = &*FI++;
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BasicBlock *BB1 = &*FI++;
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BasicBlock *BB2 = &*FI++;
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const TerminatorInst *TI = BB0->getTerminator();
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assert(TI->getNumSuccessors() == 3 && "Switch has three successors");
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BasicBlockEdge Edge_BB0_BB2(BB0, TI->getSuccessor(0));
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assert(Edge_BB0_BB2.getEnd() == BB2 &&
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"Default label is the 1st successor");
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BasicBlockEdge Edge_BB0_BB1_a(BB0, TI->getSuccessor(1));
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assert(Edge_BB0_BB1_a.getEnd() == BB1 && "BB1 is the 2nd successor");
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BasicBlockEdge Edge_BB0_BB1_b(BB0, TI->getSuccessor(2));
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assert(Edge_BB0_BB1_b.getEnd() == BB1 && "BB1 is the 3rd successor");
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EXPECT_TRUE(DT->dominates(Edge_BB0_BB2, BB2));
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EXPECT_FALSE(DT->dominates(Edge_BB0_BB2, BB1));
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EXPECT_FALSE(DT->dominates(Edge_BB0_BB1_a, BB1));
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EXPECT_FALSE(DT->dominates(Edge_BB0_BB1_b, BB1));
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EXPECT_FALSE(DT->dominates(Edge_BB0_BB1_a, BB2));
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EXPECT_FALSE(DT->dominates(Edge_BB0_BB1_b, BB2));
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});
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}
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// Verify that the PDT is correctly updated in case an edge removal results
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// in a new unreachable CFG node.
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//
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// For the following input code and initial PDT:
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//
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// CFG PDT
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//
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// A Exit
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// | |
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// _B D
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// / | \ |
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// ^ v \ B
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// \ / D / \
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// C \ C A
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// v
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// Exit
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//
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// we verify that CFG' and PDT-updated is obtained after removal of edge C -> B.
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//
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// CFG' PDT-updated
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//
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// A Exit
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// | |
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// B D
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// | \ |
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// v \ B
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// / D \
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// C \ A
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// | v
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// unreachable Exit
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//
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// WARNING: PDT-updated is inconsistent with PDT-recalculated, which is
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// constructed from CFG' when recalculating the PDT from scratch.
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//
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// PDT-recalculated
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//
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// Exit
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// / | \
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// C B D
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// |
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// A
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//
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// TODO: document the wanted behavior after resolving this inconsistency.
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TEST(DominatorTree, DeletingEdgesIntroducesUnreachables) {
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StringRef ModuleString =
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"define void @f() {\n"
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"A:\n"
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" br label %B\n"
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"B:\n"
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" br i1 undef, label %D, label %C\n"
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"C:\n"
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" br label %B\n"
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"D:\n"
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" ret void\n"
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"}\n";
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// Parse the module.
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LLVMContext Context;
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std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleString);
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runWithDomTree(
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*M, "f", [&](Function &F, DominatorTree *DT, PostDomTree *PDT) {
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Function::iterator FI = F.begin();
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FI++;
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BasicBlock *B = &*FI++;
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BasicBlock *C = &*FI++;
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BasicBlock *D = &*FI++;
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assert(PDT->dominates(PDT->getNode(D), PDT->getNode(B)));
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C->getTerminator()->eraseFromParent();
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new UnreachableInst(C->getContext(), C);
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DT->deleteEdge(C, B);
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PDT->deleteEdge(C, B);
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EXPECT_TRUE(PDT->dominates(PDT->getNode(D), PDT->getNode(B)));
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EXPECT_EQ(PDT->getNode(C), nullptr);
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PDT->recalculate(F);
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EXPECT_FALSE(PDT->dominates(PDT->getNode(D), PDT->getNode(B)));
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EXPECT_NE(PDT->getNode(C), nullptr);
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});
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}
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// Verify that the PDT is correctly updated in case an edge removal results
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// in an infinite loop.
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//
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// Test case:
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//
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// CFG PDT
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//
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// A Exit
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// | |
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// _B D
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// / | \ |
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// ^ v \ B
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// \ / D / \
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// C \ C A
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// / \ v
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// ^ v Exit
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// \_/
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//
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// After deleting the edge C->B, C is part of an infinite reverse-unreachable
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// loop:
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//
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// CFG' PDT'
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//
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// A Exit
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// | |
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// B D
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// | \ |
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// v \ B
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// / D \
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// C \ A
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// / \ v
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// ^ v Exit
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// \_/
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|
//
|
|
// In PDT, D post-dominates B. We verify that this post-dominance
|
|
// relation is preserved _after_ deleting the edge C->B from CFG.
|
|
//
|
|
// As C now becomes reverse-unreachable, it is not anymore part of the
|
|
// PDT. We also verify this property.
|
|
//
|
|
// TODO: Can we change the PDT definition such that C remains part of the
|
|
// CFG, at best without loosing the dominance relation D postdom B.
|
|
TEST(DominatorTree, DeletingEdgesIntroducesInfiniteLoop) {
|
|
StringRef ModuleString =
|
|
"define void @f() {\n"
|
|
"A:\n"
|
|
" br label %B\n"
|
|
"B:\n"
|
|
" br i1 undef, label %D, label %C\n"
|
|
"C:\n"
|
|
" switch i32 undef, label %C [\n"
|
|
" i32 0, label %B\n"
|
|
" ]\n"
|
|
"D:\n"
|
|
" ret void\n"
|
|
"}\n";
|
|
|
|
// Parse the module.
|
|
LLVMContext Context;
|
|
std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleString);
|
|
|
|
runWithDomTree(
|
|
*M, "f", [&](Function &F, DominatorTree *DT, PostDomTree *PDT) {
|
|
Function::iterator FI = F.begin();
|
|
|
|
FI++;
|
|
BasicBlock *B = &*FI++;
|
|
BasicBlock *C = &*FI++;
|
|
BasicBlock *D = &*FI++;
|
|
|
|
assert(PDT->dominates(PDT->getNode(D), PDT->getNode(B)));
|
|
|
|
auto SwitchC = cast<SwitchInst>(C->getTerminator());
|
|
SwitchC->removeCase(SwitchC->case_begin());
|
|
DT->deleteEdge(C, B);
|
|
PDT->deleteEdge(C, B);
|
|
|
|
EXPECT_TRUE(PDT->dominates(PDT->getNode(D), PDT->getNode(B)));
|
|
EXPECT_EQ(PDT->getNode(C), nullptr);
|
|
|
|
PDT->recalculate(F);
|
|
|
|
EXPECT_TRUE(PDT->dominates(PDT->getNode(D), PDT->getNode(B)));
|
|
EXPECT_EQ(PDT->getNode(C), nullptr);
|
|
});
|
|
}
|
|
|
|
// Verify that the PDT is correctly updated in case an edge removal results
|
|
// in an infinite loop.
|
|
//
|
|
// Test case:
|
|
//
|
|
// CFG PDT
|
|
//
|
|
// A Exit
|
|
// | / | \
|
|
// B-- C B D
|
|
// | \ |
|
|
// v \ A
|
|
// / D
|
|
// C--C2 \
|
|
// / \ \ v
|
|
// ^ v --Exit
|
|
// \_/
|
|
//
|
|
// After deleting the edge C->E, C is part of an infinite reverse-unreachable
|
|
// loop:
|
|
//
|
|
// CFG' PDT'
|
|
//
|
|
// A Exit
|
|
// | |
|
|
// B D
|
|
// | \ |
|
|
// v \ B
|
|
// / D \
|
|
// C \ A
|
|
// / \ v
|
|
// ^ v Exit
|
|
// \_/
|
|
//
|
|
// In PDT, D does not post-dominate B. After the edge C->E is removed, a new
|
|
// post-dominance relation is introduced.
|
|
//
|
|
// As C now becomes reverse-unreachable, it is not anymore part of the
|
|
// PDT. We also verify this property.
|
|
//
|
|
// TODO: Can we change the PDT definition such that C remains part of the
|
|
// CFG, at best without loosing the dominance relation D postdom B.
|
|
TEST(DominatorTree, DeletingEdgesIntroducesInfiniteLoop2) {
|
|
StringRef ModuleString =
|
|
"define void @f() {\n"
|
|
"A:\n"
|
|
" br label %B\n"
|
|
"B:\n"
|
|
" br i1 undef, label %D, label %C\n"
|
|
"C:\n"
|
|
" switch i32 undef, label %C [\n"
|
|
" i32 0, label %C2\n"
|
|
" ]\n"
|
|
"C2:\n"
|
|
" ret void\n"
|
|
"D:\n"
|
|
" ret void\n"
|
|
"}\n";
|
|
|
|
// Parse the module.
|
|
LLVMContext Context;
|
|
std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleString);
|
|
|
|
runWithDomTree(
|
|
*M, "f", [&](Function &F, DominatorTree *DT, PostDomTree *PDT) {
|
|
Function::iterator FI = F.begin();
|
|
|
|
FI++;
|
|
BasicBlock *B = &*FI++;
|
|
BasicBlock *C = &*FI++;
|
|
BasicBlock *C2 = &*FI++;
|
|
BasicBlock *D = &*FI++;
|
|
|
|
auto SwitchC = cast<SwitchInst>(C->getTerminator());
|
|
SwitchC->removeCase(SwitchC->case_begin());
|
|
DT->deleteEdge(C, C2);
|
|
PDT->deleteEdge(C, C2);
|
|
C2->eraseFromParent();
|
|
|
|
EXPECT_EQ(DT->getNode(C2), nullptr);
|
|
PDT->eraseNode(C2);
|
|
|
|
EXPECT_TRUE(PDT->dominates(PDT->getNode(D), PDT->getNode(B)));
|
|
EXPECT_EQ(PDT->getNode(C), nullptr);
|
|
EXPECT_EQ(PDT->getNode(C2), nullptr);
|
|
|
|
PDT->recalculate(F);
|
|
|
|
EXPECT_TRUE(PDT->dominates(PDT->getNode(D), PDT->getNode(B)));
|
|
EXPECT_EQ(PDT->getNode(C), nullptr);
|
|
EXPECT_EQ(PDT->getNode(C2), nullptr);
|
|
});
|
|
}
|
|
|
|
namespace {
|
|
const auto Insert = CFGBuilder::ActionKind::Insert;
|
|
const auto Delete = CFGBuilder::ActionKind::Delete;
|
|
|
|
bool CompUpdates(const CFGBuilder::Update &A, const CFGBuilder::Update &B) {
|
|
return std::tie(A.Action, A.Edge.From, A.Edge.To) <
|
|
std::tie(B.Action, B.Edge.From, B.Edge.To);
|
|
}
|
|
} // namespace
|
|
|
|
TEST(DominatorTree, InsertReachable) {
|
|
CFGHolder Holder;
|
|
std::vector<CFGBuilder::Arc> Arcs = {
|
|
{"1", "2"}, {"2", "3"}, {"3", "4"}, {"4", "5"}, {"5", "6"}, {"5", "7"},
|
|
{"3", "8"}, {"8", "9"}, {"9", "10"}, {"8", "11"}, {"11", "12"}};
|
|
|
|
std::vector<CFGBuilder::Update> Updates = {{Insert, {"12", "10"}},
|
|
{Insert, {"10", "9"}},
|
|
{Insert, {"7", "6"}},
|
|
{Insert, {"7", "5"}}};
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
PostDomTree PDT(*Holder.F);
|
|
EXPECT_TRUE(PDT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate;
|
|
while ((LastUpdate = B.applyUpdate())) {
|
|
EXPECT_EQ(LastUpdate->Action, Insert);
|
|
BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
|
|
BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
|
|
DT.insertEdge(From, To);
|
|
EXPECT_TRUE(DT.verify());
|
|
PDT.insertEdge(From, To);
|
|
EXPECT_TRUE(PDT.verify());
|
|
}
|
|
}
|
|
|
|
TEST(DominatorTree, InsertReachable2) {
|
|
CFGHolder Holder;
|
|
std::vector<CFGBuilder::Arc> Arcs = {
|
|
{"1", "2"}, {"2", "3"}, {"3", "4"}, {"4", "5"}, {"5", "6"}, {"5", "7"},
|
|
{"7", "5"}, {"2", "8"}, {"8", "11"}, {"11", "12"}, {"12", "10"},
|
|
{"10", "9"}, {"9", "10"}};
|
|
|
|
std::vector<CFGBuilder::Update> Updates = {{Insert, {"10", "7"}}};
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
PostDomTree PDT(*Holder.F);
|
|
EXPECT_TRUE(PDT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate = B.applyUpdate();
|
|
EXPECT_TRUE(LastUpdate);
|
|
|
|
EXPECT_EQ(LastUpdate->Action, Insert);
|
|
BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
|
|
BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
|
|
DT.insertEdge(From, To);
|
|
EXPECT_TRUE(DT.verify());
|
|
PDT.insertEdge(From, To);
|
|
EXPECT_TRUE(PDT.verify());
|
|
}
|
|
|
|
TEST(DominatorTree, InsertUnreachable) {
|
|
CFGHolder Holder;
|
|
std::vector<CFGBuilder::Arc> Arcs = {{"1", "2"}, {"2", "3"}, {"3", "4"},
|
|
{"5", "6"}, {"5", "7"}, {"3", "8"},
|
|
{"9", "10"}, {"11", "12"}};
|
|
|
|
std::vector<CFGBuilder::Update> Updates = {{Insert, {"4", "5"}},
|
|
{Insert, {"8", "9"}},
|
|
{Insert, {"10", "12"}},
|
|
{Insert, {"10", "11"}}};
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
PostDomTree PDT(*Holder.F);
|
|
EXPECT_TRUE(PDT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate;
|
|
while ((LastUpdate = B.applyUpdate())) {
|
|
EXPECT_EQ(LastUpdate->Action, Insert);
|
|
BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
|
|
BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
|
|
DT.insertEdge(From, To);
|
|
EXPECT_TRUE(DT.verify());
|
|
PDT.insertEdge(From, To);
|
|
EXPECT_TRUE(PDT.verify());
|
|
}
|
|
}
|
|
|
|
TEST(DominatorTree, InsertMixed) {
|
|
CFGHolder Holder;
|
|
std::vector<CFGBuilder::Arc> Arcs = {
|
|
{"1", "2"}, {"2", "3"}, {"3", "4"}, {"5", "6"}, {"5", "7"},
|
|
{"8", "9"}, {"9", "10"}, {"8", "11"}, {"11", "12"}, {"7", "3"}};
|
|
|
|
std::vector<CFGBuilder::Update> Updates = {
|
|
{Insert, {"4", "5"}}, {Insert, {"2", "5"}}, {Insert, {"10", "9"}},
|
|
{Insert, {"12", "10"}}, {Insert, {"12", "10"}}, {Insert, {"7", "8"}},
|
|
{Insert, {"7", "5"}}};
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
PostDomTree PDT(*Holder.F);
|
|
EXPECT_TRUE(PDT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate;
|
|
while ((LastUpdate = B.applyUpdate())) {
|
|
EXPECT_EQ(LastUpdate->Action, Insert);
|
|
BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
|
|
BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
|
|
DT.insertEdge(From, To);
|
|
EXPECT_TRUE(DT.verify());
|
|
PDT.insertEdge(From, To);
|
|
EXPECT_TRUE(PDT.verify());
|
|
}
|
|
}
|
|
|
|
TEST(DominatorTree, InsertPermut) {
|
|
std::vector<CFGBuilder::Arc> Arcs = {
|
|
{"1", "2"}, {"2", "3"}, {"3", "4"}, {"5", "6"}, {"5", "7"},
|
|
{"8", "9"}, {"9", "10"}, {"8", "11"}, {"11", "12"}, {"7", "3"}};
|
|
|
|
std::vector<CFGBuilder::Update> Updates = {{Insert, {"4", "5"}},
|
|
{Insert, {"2", "5"}},
|
|
{Insert, {"10", "9"}},
|
|
{Insert, {"12", "10"}}};
|
|
|
|
while (std::next_permutation(Updates.begin(), Updates.end(), CompUpdates)) {
|
|
CFGHolder Holder;
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
PostDomTree PDT(*Holder.F);
|
|
EXPECT_TRUE(PDT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate;
|
|
while ((LastUpdate = B.applyUpdate())) {
|
|
EXPECT_EQ(LastUpdate->Action, Insert);
|
|
BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
|
|
BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
|
|
DT.insertEdge(From, To);
|
|
EXPECT_TRUE(DT.verify());
|
|
PDT.insertEdge(From, To);
|
|
EXPECT_TRUE(PDT.verify());
|
|
}
|
|
}
|
|
}
|
|
|
|
TEST(DominatorTree, DeleteReachable) {
|
|
CFGHolder Holder;
|
|
std::vector<CFGBuilder::Arc> Arcs = {
|
|
{"1", "2"}, {"2", "3"}, {"2", "4"}, {"3", "4"}, {"4", "5"}, {"5", "6"},
|
|
{"5", "7"}, {"7", "8"}, {"3", "8"}, {"8", "9"}, {"9", "10"}, {"10", "2"}};
|
|
|
|
std::vector<CFGBuilder::Update> Updates = {
|
|
{Delete, {"2", "4"}}, {Delete, {"7", "8"}}, {Delete, {"10", "2"}}};
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
PostDomTree PDT(*Holder.F);
|
|
EXPECT_TRUE(PDT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate;
|
|
while ((LastUpdate = B.applyUpdate())) {
|
|
EXPECT_EQ(LastUpdate->Action, Delete);
|
|
BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
|
|
BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
|
|
DT.deleteEdge(From, To);
|
|
EXPECT_TRUE(DT.verify());
|
|
PDT.deleteEdge(From, To);
|
|
EXPECT_TRUE(PDT.verify());
|
|
}
|
|
}
|
|
|
|
TEST(DominatorTree, DeleteUnreachable) {
|
|
CFGHolder Holder;
|
|
std::vector<CFGBuilder::Arc> Arcs = {
|
|
{"1", "2"}, {"2", "3"}, {"3", "4"}, {"4", "5"}, {"5", "6"}, {"5", "7"},
|
|
{"7", "8"}, {"3", "8"}, {"8", "9"}, {"9", "10"}, {"10", "2"}};
|
|
|
|
std::vector<CFGBuilder::Update> Updates = {
|
|
{Delete, {"8", "9"}}, {Delete, {"7", "8"}}, {Delete, {"3", "4"}}};
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
PostDomTree PDT(*Holder.F);
|
|
EXPECT_TRUE(PDT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate;
|
|
while ((LastUpdate = B.applyUpdate())) {
|
|
EXPECT_EQ(LastUpdate->Action, Delete);
|
|
BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
|
|
BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
|
|
DT.deleteEdge(From, To);
|
|
EXPECT_TRUE(DT.verify());
|
|
PDT.deleteEdge(From, To);
|
|
EXPECT_TRUE(PDT.verify());
|
|
}
|
|
}
|
|
|
|
TEST(DominatorTree, DeletionsInSubtrees) {
|
|
CFGHolder Holder;
|
|
std::vector<CFGBuilder::Arc> Arcs = {{"0", "1"}, {"1", "2"}, {"1", "3"},
|
|
{"1", "6"}, {"3", "4"}, {"2", "5"},
|
|
{"5", "2"}};
|
|
|
|
// It is possible to perform multiple deletions and inform the
|
|
// DominatorTree about them at the same time, if the all of the
|
|
// deletions happen in different subtrees.
|
|
std::vector<CFGBuilder::Update> Updates = {{Delete, {"1", "2"}},
|
|
{Delete, {"1", "3"}}};
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate;
|
|
while ((LastUpdate = B.applyUpdate()))
|
|
;
|
|
|
|
DT.deleteEdge(B.getOrAddBlock("1"), B.getOrAddBlock("2"));
|
|
DT.deleteEdge(B.getOrAddBlock("1"), B.getOrAddBlock("3"));
|
|
|
|
EXPECT_TRUE(DT.verify());
|
|
EXPECT_EQ(DT.getNode(B.getOrAddBlock("2")), nullptr);
|
|
EXPECT_EQ(DT.getNode(B.getOrAddBlock("3")), nullptr);
|
|
EXPECT_EQ(DT.getNode(B.getOrAddBlock("4")), nullptr);
|
|
EXPECT_EQ(DT.getNode(B.getOrAddBlock("5")), nullptr);
|
|
EXPECT_NE(DT.getNode(B.getOrAddBlock("6")), nullptr);
|
|
}
|
|
|
|
TEST(DominatorTree, InsertDelete) {
|
|
std::vector<CFGBuilder::Arc> Arcs = {
|
|
{"1", "2"}, {"2", "3"}, {"3", "4"}, {"4", "5"}, {"5", "6"}, {"5", "7"},
|
|
{"3", "8"}, {"8", "9"}, {"9", "10"}, {"8", "11"}, {"11", "12"}};
|
|
|
|
std::vector<CFGBuilder::Update> Updates = {
|
|
{Insert, {"2", "4"}}, {Insert, {"12", "10"}}, {Insert, {"10", "9"}},
|
|
{Insert, {"7", "6"}}, {Insert, {"7", "5"}}, {Delete, {"3", "8"}},
|
|
{Insert, {"10", "7"}}, {Insert, {"2", "8"}}, {Delete, {"3", "4"}},
|
|
{Delete, {"8", "9"}}, {Delete, {"11", "12"}}};
|
|
|
|
CFGHolder Holder;
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
PostDomTree PDT(*Holder.F);
|
|
EXPECT_TRUE(PDT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate;
|
|
while ((LastUpdate = B.applyUpdate())) {
|
|
BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
|
|
BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
|
|
if (LastUpdate->Action == Insert) {
|
|
DT.insertEdge(From, To);
|
|
PDT.insertEdge(From, To);
|
|
} else {
|
|
DT.deleteEdge(From, To);
|
|
PDT.deleteEdge(From, To);
|
|
}
|
|
|
|
EXPECT_TRUE(DT.verify());
|
|
EXPECT_TRUE(PDT.verify());
|
|
}
|
|
}
|
|
|
|
TEST(DominatorTree, InsertDeleteExhaustive) {
|
|
std::vector<CFGBuilder::Arc> Arcs = {
|
|
{"1", "2"}, {"2", "3"}, {"3", "4"}, {"4", "5"}, {"5", "6"}, {"5", "7"},
|
|
{"3", "8"}, {"8", "9"}, {"9", "10"}, {"8", "11"}, {"11", "12"}};
|
|
|
|
std::vector<CFGBuilder::Update> Updates = {
|
|
{Insert, {"2", "4"}}, {Insert, {"12", "10"}}, {Insert, {"10", "9"}},
|
|
{Insert, {"7", "6"}}, {Insert, {"7", "5"}}, {Delete, {"3", "8"}},
|
|
{Insert, {"10", "7"}}, {Insert, {"2", "8"}}, {Delete, {"3", "4"}},
|
|
{Delete, {"8", "9"}}, {Delete, {"11", "12"}}};
|
|
|
|
std::mt19937 Generator(0);
|
|
for (unsigned i = 0; i < 16; ++i) {
|
|
std::shuffle(Updates.begin(), Updates.end(), Generator);
|
|
CFGHolder Holder;
|
|
CFGBuilder B(Holder.F, Arcs, Updates);
|
|
DominatorTree DT(*Holder.F);
|
|
EXPECT_TRUE(DT.verify());
|
|
PostDomTree PDT(*Holder.F);
|
|
EXPECT_TRUE(PDT.verify());
|
|
|
|
Optional<CFGBuilder::Update> LastUpdate;
|
|
while ((LastUpdate = B.applyUpdate())) {
|
|
BasicBlock *From = B.getOrAddBlock(LastUpdate->Edge.From);
|
|
BasicBlock *To = B.getOrAddBlock(LastUpdate->Edge.To);
|
|
if (LastUpdate->Action == Insert) {
|
|
DT.insertEdge(From, To);
|
|
PDT.insertEdge(From, To);
|
|
} else {
|
|
DT.deleteEdge(From, To);
|
|
PDT.deleteEdge(From, To);
|
|
}
|
|
|
|
EXPECT_TRUE(DT.verify());
|
|
EXPECT_TRUE(PDT.verify());
|
|
}
|
|
}
|
|
}
|