unittests/IR/DominatorTreeBatchUpdatesTest.cpp - llvm-project/llvm - Git at Google

 //===- llvm/unittests/IR/DominatorTreeBatchUpdatesTest.cpp ----------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//

 #include <random>
 #include "CFGBuilder.h"
 #include "gtest/gtest.h"
 #include "llvm/Analysis/PostDominators.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/Support/GenericDomTreeConstruction.h"

 #define DEBUG_TYPE "batch-update-tests"

 using namespace llvm;

 namespace {
 const auto CFGInsert = CFGBuilder::ActionKind::Insert;
 const auto CFGDelete = CFGBuilder::ActionKind::Delete;


 using DomUpdate = DominatorTree::UpdateType;
 static_assert(
     std::is_same<DomUpdate, PostDominatorTree::UpdateType>::value,
     "Trees differing only in IsPostDom should have the same update types");
 using DomSNCA = DomTreeBuilder::SemiNCAInfo<DomTreeBuilder::BBDomTree>;
 using PostDomSNCA = DomTreeBuilder::SemiNCAInfo<DomTreeBuilder::BBPostDomTree>;
 const auto Insert = DominatorTree::Insert;
 const auto Delete = DominatorTree::Delete;

 std::vector<DomUpdate> ToDomUpdates(CFGBuilder &B,
                                     std::vector<CFGBuilder::Update> &In) {
   std::vector<DomUpdate> Res;
   Res.reserve(In.size());

   for (const auto &CFGU : In)
     Res.push_back({CFGU.Action == CFGInsert ? Insert : Delete,
                    B.getOrAddBlock(CFGU.Edge.From),
                    B.getOrAddBlock(CFGU.Edge.To)});
   return Res;
 }
 }  // namespace

 TEST(DominatorTreeBatchUpdates, LegalizeDomUpdates) {
   CFGHolder Holder;
   CFGBuilder Builder(Holder.F, {{"A", "B"}}, {});

   BasicBlock *A = Builder.getOrAddBlock("A");
   BasicBlock *B = Builder.getOrAddBlock("B");
   BasicBlock *C = Builder.getOrAddBlock("C");
   BasicBlock *D = Builder.getOrAddBlock("D");

   std::vector<DomUpdate> Updates = {
       {Insert, B, C}, {Insert, C, D}, {Delete, B, C}, {Insert, B, C},
       {Insert, B, D}, {Delete, C, D}, {Delete, A, B}};
   SmallVector<DomUpdate, 4> Legalized;
   cfg::LegalizeUpdates<BasicBlock *>(Updates, Legalized, false);
   LLVM_DEBUG(dbgs() << "Legalized updates:\t");
   LLVM_DEBUG(for (auto &U : Legalized) { U.dump(); dbgs() << ", "; });
   LLVM_DEBUG(dbgs() << "\n");
   EXPECT_EQ(Legalized.size(), 3UL);
   EXPECT_NE(llvm::find(Legalized, DomUpdate{Insert, B, C}), Legalized.end());
   EXPECT_NE(llvm::find(Legalized, DomUpdate{Insert, B, D}), Legalized.end());
   EXPECT_NE(llvm::find(Legalized, DomUpdate{Delete, A, B}), Legalized.end());
 }

 TEST(DominatorTreeBatchUpdates, LegalizePostDomUpdates) {
   CFGHolder Holder;
   CFGBuilder Builder(Holder.F, {{"A", "B"}}, {});

   BasicBlock *A = Builder.getOrAddBlock("A");
   BasicBlock *B = Builder.getOrAddBlock("B");
   BasicBlock *C = Builder.getOrAddBlock("C");
   BasicBlock *D = Builder.getOrAddBlock("D");

   std::vector<DomUpdate> Updates = {
       {Insert, B, C}, {Insert, C, D}, {Delete, B, C}, {Insert, B, C},
       {Insert, B, D}, {Delete, C, D}, {Delete, A, B}};
   SmallVector<DomUpdate, 4> Legalized;
   cfg::LegalizeUpdates<BasicBlock *>(Updates, Legalized, true);
   LLVM_DEBUG(dbgs() << "Legalized postdom updates:\t");
   LLVM_DEBUG(for (auto &U : Legalized) { U.dump(); dbgs() << ", "; });
   LLVM_DEBUG(dbgs() << "\n");
   EXPECT_EQ(Legalized.size(), 3UL);
   EXPECT_NE(llvm::find(Legalized, DomUpdate{Insert, C, B}), Legalized.end());
   EXPECT_NE(llvm::find(Legalized, DomUpdate{Insert, D, B}), Legalized.end());
   EXPECT_NE(llvm::find(Legalized, DomUpdate{Delete, B, A}), Legalized.end());
 }

 TEST(DominatorTreeBatchUpdates, SingleInsertion) {
   CFGHolder Holder;
   CFGBuilder Builder(Holder.F, {{"A", "B"}}, {{CFGInsert, {"B", "C"}}});

   DominatorTree DT(*Holder.F);
   EXPECT_TRUE(DT.verify());
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());

   BasicBlock *B = Builder.getOrAddBlock("B");
   BasicBlock *C = Builder.getOrAddBlock("C");
   std::vector<DomUpdate> Updates = {{Insert, B, C}};

   ASSERT_TRUE(Builder.applyUpdate());

   DT.applyUpdates(Updates);
   EXPECT_TRUE(DT.verify());
   PDT.applyUpdates(Updates);
   EXPECT_TRUE(PDT.verify());
 }

 TEST(DominatorTreeBatchUpdates, SingleDeletion) {
   CFGHolder Holder;
   CFGBuilder Builder(Holder.F, {{"A", "B"}, {"B", "C"}},
                      {{CFGDelete, {"B", "C"}}});

   DominatorTree DT(*Holder.F);
   EXPECT_TRUE(DT.verify());
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());

   BasicBlock *B = Builder.getOrAddBlock("B");
   BasicBlock *C = Builder.getOrAddBlock("C");
   std::vector<DomUpdate> Updates = {{Delete, B, C}};

   ASSERT_TRUE(Builder.applyUpdate());

   DT.applyUpdates(Updates);
   EXPECT_TRUE(DT.verify());
   PDT.applyUpdates(Updates);
   EXPECT_TRUE(PDT.verify());
 }

 TEST(DominatorTreeBatchUpdates, FewInsertion) {
   std::vector<CFGBuilder::Update> CFGUpdates = {{CFGInsert, {"B", "C"}},
                                                 {CFGInsert, {"C", "B"}},
                                                 {CFGInsert, {"C", "D"}},
                                                 {CFGInsert, {"D", "E"}}};

   CFGHolder Holder;
   CFGBuilder Builder(Holder.F, {{"A", "B"}}, CFGUpdates);

   DominatorTree DT(*Holder.F);
   EXPECT_TRUE(DT.verify());
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());

   BasicBlock *B = Builder.getOrAddBlock("B");
   BasicBlock *C = Builder.getOrAddBlock("C");
   BasicBlock *D = Builder.getOrAddBlock("D");
   BasicBlock *E = Builder.getOrAddBlock("E");

   std::vector<DomUpdate> Updates = {
       {Insert, B, C}, {Insert, C, B}, {Insert, C, D}, {Insert, D, E}};

   while (Builder.applyUpdate())
     ;

   DT.applyUpdates(Updates);
   EXPECT_TRUE(DT.verify());
   PDT.applyUpdates(Updates);
   EXPECT_TRUE(PDT.verify());
 }

 TEST(DominatorTreeBatchUpdates, FewDeletions) {
   std::vector<CFGBuilder::Update> CFGUpdates = {{CFGDelete, {"B", "C"}},
                                                 {CFGDelete, {"C", "B"}},
                                                 {CFGDelete, {"B", "D"}},
                                                 {CFGDelete, {"D", "E"}}};

   CFGHolder Holder;
   CFGBuilder Builder(
       Holder.F, {{"A", "B"}, {"B", "C"}, {"B", "D"}, {"D", "E"}, {"C", "B"}},
       CFGUpdates);

   DominatorTree DT(*Holder.F);
   EXPECT_TRUE(DT.verify());
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());

   auto Updates = ToDomUpdates(Builder, CFGUpdates);

   while (Builder.applyUpdate())
     ;

   DT.applyUpdates(Updates);
   EXPECT_TRUE(DT.verify());
   PDT.applyUpdates(Updates);
   EXPECT_TRUE(PDT.verify());
 }

 TEST(DominatorTreeBatchUpdates, 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 = {
       {CFGInsert, {"2", "4"}},  {CFGInsert, {"12", "10"}},
       {CFGInsert, {"10", "9"}}, {CFGInsert, {"7", "6"}},
       {CFGInsert, {"7", "5"}},  {CFGDelete, {"3", "8"}},
       {CFGInsert, {"10", "7"}}, {CFGInsert, {"2", "8"}},
       {CFGDelete, {"3", "4"}},  {CFGDelete, {"8", "9"}},
       {CFGDelete, {"11", "12"}}};

   CFGHolder Holder;
   CFGBuilder B(Holder.F, Arcs, Updates);
   DominatorTree DT(*Holder.F);
   EXPECT_TRUE(DT.verify());
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());

   while (B.applyUpdate())
     ;

   auto DomUpdates = ToDomUpdates(B, Updates);
   DT.applyUpdates(DomUpdates);
   EXPECT_TRUE(DT.verify());
   PDT.applyUpdates(DomUpdates);
   EXPECT_TRUE(PDT.verify());
 }

 TEST(DominatorTreeBatchUpdates, 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 = {
       {CFGInsert, {"2", "4"}},  {CFGInsert, {"12", "10"}},
       {CFGInsert, {"10", "9"}}, {CFGInsert, {"7", "6"}},
       {CFGInsert, {"7", "5"}},  {CFGDelete, {"3", "8"}},
       {CFGInsert, {"10", "7"}}, {CFGInsert, {"2", "8"}},
       {CFGDelete, {"3", "4"}},  {CFGDelete, {"8", "9"}},
       {CFGDelete, {"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());
     PostDominatorTree PDT(*Holder.F);
     EXPECT_TRUE(PDT.verify());

     while (B.applyUpdate())
       ;

     auto DomUpdates = ToDomUpdates(B, Updates);
     DT.applyUpdates(DomUpdates);
     EXPECT_TRUE(DT.verify());
     PDT.applyUpdates(DomUpdates);
     EXPECT_TRUE(PDT.verify());
   }
 }

 // These are some odd flowgraphs, usually generated from csmith cases,
 // which are difficult on post dom trees.
 TEST(DominatorTreeBatchUpdates, InfiniteLoop) {
   std::vector<CFGBuilder::Arc> Arcs = {
       {"1", "2"},
       {"2", "3"},
       {"3", "6"}, {"3", "5"},
       {"4", "5"},
       {"5", "2"},
       {"6", "3"}, {"6", "4"}};

   // SplitBlock on 3 -> 5
   std::vector<CFGBuilder::Update> Updates = {
       {CFGInsert, {"N", "5"}},  {CFGInsert, {"3", "N"}}, {CFGDelete, {"3", "5"}}};

   CFGHolder Holder;
   CFGBuilder B(Holder.F, Arcs, Updates);
   DominatorTree DT(*Holder.F);
   EXPECT_TRUE(DT.verify());
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());

   while (B.applyUpdate())
     ;

   auto DomUpdates = ToDomUpdates(B, Updates);
   DT.applyUpdates(DomUpdates);
   EXPECT_TRUE(DT.verify());
   PDT.applyUpdates(DomUpdates);
   EXPECT_TRUE(PDT.verify());
 }

 TEST(DominatorTreeBatchUpdates, DeadBlocks) {
   std::vector<CFGBuilder::Arc> Arcs = {
       {"1", "2"},
       {"2", "3"},
       {"3", "4"}, {"3", "7"},
       {"4", "4"},
       {"5", "6"}, {"5", "7"},
       {"6", "7"},
       {"7", "2"}, {"7", "8"}};

   // Remove dead 5 and 7,
   // plus SplitBlock on 7 -> 8
   std::vector<CFGBuilder::Update> Updates = {
       {CFGDelete, {"6", "7"}},  {CFGDelete, {"5", "7"}}, {CFGDelete, {"5", "6"}},
       {CFGInsert, {"N", "8"}},  {CFGInsert, {"7", "N"}}, {CFGDelete, {"7", "8"}}};

   CFGHolder Holder;
   CFGBuilder B(Holder.F, Arcs, Updates);
   DominatorTree DT(*Holder.F);
   EXPECT_TRUE(DT.verify());
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());

   while (B.applyUpdate())
     ;

   auto DomUpdates = ToDomUpdates(B, Updates);
   DT.applyUpdates(DomUpdates);
   EXPECT_TRUE(DT.verify());
   PDT.applyUpdates(DomUpdates);
   EXPECT_TRUE(PDT.verify());
 }

 TEST(DominatorTreeBatchUpdates, InfiniteLoop2) {
   std::vector<CFGBuilder::Arc> Arcs = {
       {"1", "2"},
       {"2", "6"}, {"2", "3"},
       {"3", "4"},
       {"4", "5"}, {"4", "6"},
       {"5", "4"},
       {"6", "2"}};

   // SplitBlock on 4 -> 6
   std::vector<CFGBuilder::Update> Updates = {
       {CFGInsert, {"N", "6"}},  {CFGInsert, {"4", "N"}}, {CFGDelete, {"4", "6"}}};

   CFGHolder Holder;
   CFGBuilder B(Holder.F, Arcs, Updates);
   DominatorTree DT(*Holder.F);
   EXPECT_TRUE(DT.verify());
   PostDominatorTree PDT(*Holder.F);
   EXPECT_TRUE(PDT.verify());

   while (B.applyUpdate())
     ;

   auto DomUpdates = ToDomUpdates(B, Updates);
   DT.applyUpdates(DomUpdates);
   EXPECT_TRUE(DT.verify());
   PDT.applyUpdates(DomUpdates);
   EXPECT_TRUE(PDT.verify());
 }
	//===- llvm/unittests/IR/DominatorTreeBatchUpdatesTest.cpp ----------------===//
	//
	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	// See https://llvm.org/LICENSE.txt for license information.
	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	//
	//===----------------------------------------------------------------------===//

	#include <random>
	#include "CFGBuilder.h"
	#include "gtest/gtest.h"
	#include "llvm/Analysis/PostDominators.h"
	#include "llvm/IR/Dominators.h"
	#include "llvm/Support/GenericDomTreeConstruction.h"

	#define DEBUG_TYPE "batch-update-tests"

	using namespace llvm;

	namespace {
	const auto CFGInsert = CFGBuilder::ActionKind::Insert;
	const auto CFGDelete = CFGBuilder::ActionKind::Delete;


	using DomUpdate = DominatorTree::UpdateType;
	static_assert(
	std::is_same<DomUpdate, PostDominatorTree::UpdateType>::value,
	"Trees differing only in IsPostDom should have the same update types");
	using DomSNCA = DomTreeBuilder::SemiNCAInfo<DomTreeBuilder::BBDomTree>;
	using PostDomSNCA = DomTreeBuilder::SemiNCAInfo<DomTreeBuilder::BBPostDomTree>;
	const auto Insert = DominatorTree::Insert;
	const auto Delete = DominatorTree::Delete;

	std::vector<DomUpdate> ToDomUpdates(CFGBuilder &B,
	std::vector<CFGBuilder::Update> &In) {
	std::vector<DomUpdate> Res;
	Res.reserve(In.size());

	for (const auto &CFGU : In)
	Res.push_back({CFGU.Action == CFGInsert ? Insert : Delete,
	B.getOrAddBlock(CFGU.Edge.From),
	B.getOrAddBlock(CFGU.Edge.To)});
	return Res;
	}
	} // namespace

	TEST(DominatorTreeBatchUpdates, LegalizeDomUpdates) {
	CFGHolder Holder;
	CFGBuilder Builder(Holder.F, {{"A", "B"}}, {});

	BasicBlock *A = Builder.getOrAddBlock("A");
	BasicBlock *B = Builder.getOrAddBlock("B");
	BasicBlock *C = Builder.getOrAddBlock("C");
	BasicBlock *D = Builder.getOrAddBlock("D");

	std::vector<DomUpdate> Updates = {
	{Insert, B, C}, {Insert, C, D}, {Delete, B, C}, {Insert, B, C},
	{Insert, B, D}, {Delete, C, D}, {Delete, A, B}};
	SmallVector<DomUpdate, 4> Legalized;
	cfg::LegalizeUpdates<BasicBlock *>(Updates, Legalized, false);
	LLVM_DEBUG(dbgs() << "Legalized updates:\t");
	LLVM_DEBUG(for (auto &U : Legalized) { U.dump(); dbgs() << ", "; });
	LLVM_DEBUG(dbgs() << "\n");
	EXPECT_EQ(Legalized.size(), 3UL);
	EXPECT_NE(llvm::find(Legalized, DomUpdate{Insert, B, C}), Legalized.end());
	EXPECT_NE(llvm::find(Legalized, DomUpdate{Insert, B, D}), Legalized.end());
	EXPECT_NE(llvm::find(Legalized, DomUpdate{Delete, A, B}), Legalized.end());
	}

	TEST(DominatorTreeBatchUpdates, LegalizePostDomUpdates) {
	CFGHolder Holder;
	CFGBuilder Builder(Holder.F, {{"A", "B"}}, {});

	BasicBlock *A = Builder.getOrAddBlock("A");
	BasicBlock *B = Builder.getOrAddBlock("B");
	BasicBlock *C = Builder.getOrAddBlock("C");
	BasicBlock *D = Builder.getOrAddBlock("D");

	std::vector<DomUpdate> Updates = {
	{Insert, B, C}, {Insert, C, D}, {Delete, B, C}, {Insert, B, C},
	{Insert, B, D}, {Delete, C, D}, {Delete, A, B}};
	SmallVector<DomUpdate, 4> Legalized;
	cfg::LegalizeUpdates<BasicBlock *>(Updates, Legalized, true);
	LLVM_DEBUG(dbgs() << "Legalized postdom updates:\t");
	LLVM_DEBUG(for (auto &U : Legalized) { U.dump(); dbgs() << ", "; });
	LLVM_DEBUG(dbgs() << "\n");
	EXPECT_EQ(Legalized.size(), 3UL);
	EXPECT_NE(llvm::find(Legalized, DomUpdate{Insert, C, B}), Legalized.end());
	EXPECT_NE(llvm::find(Legalized, DomUpdate{Insert, D, B}), Legalized.end());
	EXPECT_NE(llvm::find(Legalized, DomUpdate{Delete, B, A}), Legalized.end());
	}

	TEST(DominatorTreeBatchUpdates, SingleInsertion) {
	CFGHolder Holder;
	CFGBuilder Builder(Holder.F, {{"A", "B"}}, {{CFGInsert, {"B", "C"}}});

	DominatorTree DT(*Holder.F);
	EXPECT_TRUE(DT.verify());
	PostDominatorTree PDT(*Holder.F);
	EXPECT_TRUE(PDT.verify());

	BasicBlock *B = Builder.getOrAddBlock("B");
	BasicBlock *C = Builder.getOrAddBlock("C");
	std::vector<DomUpdate> Updates = {{Insert, B, C}};

	ASSERT_TRUE(Builder.applyUpdate());

	DT.applyUpdates(Updates);
	EXPECT_TRUE(DT.verify());
	PDT.applyUpdates(Updates);
	EXPECT_TRUE(PDT.verify());
	}

	TEST(DominatorTreeBatchUpdates, SingleDeletion) {
	CFGHolder Holder;
	CFGBuilder Builder(Holder.F, {{"A", "B"}, {"B", "C"}},
	{{CFGDelete, {"B", "C"}}});

	DominatorTree DT(*Holder.F);
	EXPECT_TRUE(DT.verify());
	PostDominatorTree PDT(*Holder.F);
	EXPECT_TRUE(PDT.verify());

	BasicBlock *B = Builder.getOrAddBlock("B");
	BasicBlock *C = Builder.getOrAddBlock("C");
	std::vector<DomUpdate> Updates = {{Delete, B, C}};

	ASSERT_TRUE(Builder.applyUpdate());

	DT.applyUpdates(Updates);
	EXPECT_TRUE(DT.verify());
	PDT.applyUpdates(Updates);
	EXPECT_TRUE(PDT.verify());
	}

	TEST(DominatorTreeBatchUpdates, FewInsertion) {
	std::vector<CFGBuilder::Update> CFGUpdates = {{CFGInsert, {"B", "C"}},
	{CFGInsert, {"C", "B"}},
	{CFGInsert, {"C", "D"}},
	{CFGInsert, {"D", "E"}}};

	CFGHolder Holder;
	CFGBuilder Builder(Holder.F, {{"A", "B"}}, CFGUpdates);

	DominatorTree DT(*Holder.F);
	EXPECT_TRUE(DT.verify());
	PostDominatorTree PDT(*Holder.F);
	EXPECT_TRUE(PDT.verify());

	BasicBlock *B = Builder.getOrAddBlock("B");
	BasicBlock *C = Builder.getOrAddBlock("C");
	BasicBlock *D = Builder.getOrAddBlock("D");
	BasicBlock *E = Builder.getOrAddBlock("E");

	std::vector<DomUpdate> Updates = {
	{Insert, B, C}, {Insert, C, B}, {Insert, C, D}, {Insert, D, E}};

	while (Builder.applyUpdate())
	;

	DT.applyUpdates(Updates);
	EXPECT_TRUE(DT.verify());
	PDT.applyUpdates(Updates);
	EXPECT_TRUE(PDT.verify());
	}

	TEST(DominatorTreeBatchUpdates, FewDeletions) {
	std::vector<CFGBuilder::Update> CFGUpdates = {{CFGDelete, {"B", "C"}},
	{CFGDelete, {"C", "B"}},
	{CFGDelete, {"B", "D"}},
	{CFGDelete, {"D", "E"}}};

	CFGHolder Holder;
	CFGBuilder Builder(
	Holder.F, {{"A", "B"}, {"B", "C"}, {"B", "D"}, {"D", "E"}, {"C", "B"}},
	CFGUpdates);

	DominatorTree DT(*Holder.F);
	EXPECT_TRUE(DT.verify());
	PostDominatorTree PDT(*Holder.F);
	EXPECT_TRUE(PDT.verify());

	auto Updates = ToDomUpdates(Builder, CFGUpdates);

	while (Builder.applyUpdate())
	;

	DT.applyUpdates(Updates);
	EXPECT_TRUE(DT.verify());
	PDT.applyUpdates(Updates);
	EXPECT_TRUE(PDT.verify());
	}

	TEST(DominatorTreeBatchUpdates, 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 = {
	{CFGInsert, {"2", "4"}}, {CFGInsert, {"12", "10"}},
	{CFGInsert, {"10", "9"}}, {CFGInsert, {"7", "6"}},
	{CFGInsert, {"7", "5"}}, {CFGDelete, {"3", "8"}},
	{CFGInsert, {"10", "7"}}, {CFGInsert, {"2", "8"}},
	{CFGDelete, {"3", "4"}}, {CFGDelete, {"8", "9"}},
	{CFGDelete, {"11", "12"}}};

	CFGHolder Holder;
	CFGBuilder B(Holder.F, Arcs, Updates);
	DominatorTree DT(*Holder.F);
	EXPECT_TRUE(DT.verify());
	PostDominatorTree PDT(*Holder.F);
	EXPECT_TRUE(PDT.verify());

	while (B.applyUpdate())
	;

	auto DomUpdates = ToDomUpdates(B, Updates);
	DT.applyUpdates(DomUpdates);
	EXPECT_TRUE(DT.verify());
	PDT.applyUpdates(DomUpdates);
	EXPECT_TRUE(PDT.verify());
	}

	TEST(DominatorTreeBatchUpdates, 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 = {
	{CFGInsert, {"2", "4"}}, {CFGInsert, {"12", "10"}},
	{CFGInsert, {"10", "9"}}, {CFGInsert, {"7", "6"}},
	{CFGInsert, {"7", "5"}}, {CFGDelete, {"3", "8"}},
	{CFGInsert, {"10", "7"}}, {CFGInsert, {"2", "8"}},
	{CFGDelete, {"3", "4"}}, {CFGDelete, {"8", "9"}},
	{CFGDelete, {"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());
	PostDominatorTree PDT(*Holder.F);
	EXPECT_TRUE(PDT.verify());

	while (B.applyUpdate())
	;

	auto DomUpdates = ToDomUpdates(B, Updates);
	DT.applyUpdates(DomUpdates);
	EXPECT_TRUE(DT.verify());
	PDT.applyUpdates(DomUpdates);
	EXPECT_TRUE(PDT.verify());
	}
	}

	// These are some odd flowgraphs, usually generated from csmith cases,
	// which are difficult on post dom trees.
	TEST(DominatorTreeBatchUpdates, InfiniteLoop) {
	std::vector<CFGBuilder::Arc> Arcs = {
	{"1", "2"},
	{"2", "3"},
	{"3", "6"}, {"3", "5"},
	{"4", "5"},
	{"5", "2"},
	{"6", "3"}, {"6", "4"}};

	// SplitBlock on 3 -> 5
	std::vector<CFGBuilder::Update> Updates = {
	{CFGInsert, {"N", "5"}}, {CFGInsert, {"3", "N"}}, {CFGDelete, {"3", "5"}}};

	CFGHolder Holder;
	CFGBuilder B(Holder.F, Arcs, Updates);
	DominatorTree DT(*Holder.F);
	EXPECT_TRUE(DT.verify());
	PostDominatorTree PDT(*Holder.F);
	EXPECT_TRUE(PDT.verify());

	while (B.applyUpdate())
	;

	auto DomUpdates = ToDomUpdates(B, Updates);
	DT.applyUpdates(DomUpdates);
	EXPECT_TRUE(DT.verify());
	PDT.applyUpdates(DomUpdates);
	EXPECT_TRUE(PDT.verify());
	}

	TEST(DominatorTreeBatchUpdates, DeadBlocks) {
	std::vector<CFGBuilder::Arc> Arcs = {
	{"1", "2"},
	{"2", "3"},
	{"3", "4"}, {"3", "7"},
	{"4", "4"},
	{"5", "6"}, {"5", "7"},
	{"6", "7"},
	{"7", "2"}, {"7", "8"}};

	// Remove dead 5 and 7,
	// plus SplitBlock on 7 -> 8
	std::vector<CFGBuilder::Update> Updates = {
	{CFGDelete, {"6", "7"}}, {CFGDelete, {"5", "7"}}, {CFGDelete, {"5", "6"}},
	{CFGInsert, {"N", "8"}}, {CFGInsert, {"7", "N"}}, {CFGDelete, {"7", "8"}}};

	CFGHolder Holder;
	CFGBuilder B(Holder.F, Arcs, Updates);
	DominatorTree DT(*Holder.F);
	EXPECT_TRUE(DT.verify());
	PostDominatorTree PDT(*Holder.F);
	EXPECT_TRUE(PDT.verify());

	while (B.applyUpdate())
	;

	auto DomUpdates = ToDomUpdates(B, Updates);
	DT.applyUpdates(DomUpdates);
	EXPECT_TRUE(DT.verify());
	PDT.applyUpdates(DomUpdates);
	EXPECT_TRUE(PDT.verify());
	}

	TEST(DominatorTreeBatchUpdates, InfiniteLoop2) {
	std::vector<CFGBuilder::Arc> Arcs = {
	{"1", "2"},
	{"2", "6"}, {"2", "3"},
	{"3", "4"},
	{"4", "5"}, {"4", "6"},
	{"5", "4"},
	{"6", "2"}};

	// SplitBlock on 4 -> 6
	std::vector<CFGBuilder::Update> Updates = {
	{CFGInsert, {"N", "6"}}, {CFGInsert, {"4", "N"}}, {CFGDelete, {"4", "6"}}};

	CFGHolder Holder;
	CFGBuilder B(Holder.F, Arcs, Updates);
	DominatorTree DT(*Holder.F);
	EXPECT_TRUE(DT.verify());
	PostDominatorTree PDT(*Holder.F);
	EXPECT_TRUE(PDT.verify());

	while (B.applyUpdate())
	;

	auto DomUpdates = ToDomUpdates(B, Updates);
	DT.applyUpdates(DomUpdates);
	EXPECT_TRUE(DT.verify());
	PDT.applyUpdates(DomUpdates);
	EXPECT_TRUE(PDT.verify());
	}