762 lines · cpp
1//===- llvm-stress.cpp - Generate random LL files to stress-test LLVM -----===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This program is a utility that generates random .ll files to stress-test10// different components in LLVM.11//12//===----------------------------------------------------------------------===//13 14#include "llvm/ADT/APFloat.h"15#include "llvm/ADT/APInt.h"16#include "llvm/ADT/ArrayRef.h"17#include "llvm/ADT/STLExtras.h"18#include "llvm/ADT/StringRef.h"19#include "llvm/ADT/Twine.h"20#include "llvm/IR/BasicBlock.h"21#include "llvm/IR/CallingConv.h"22#include "llvm/IR/Constants.h"23#include "llvm/IR/DataLayout.h"24#include "llvm/IR/DerivedTypes.h"25#include "llvm/IR/Function.h"26#include "llvm/IR/GlobalValue.h"27#include "llvm/IR/InstrTypes.h"28#include "llvm/IR/Instruction.h"29#include "llvm/IR/Instructions.h"30#include "llvm/IR/LLVMContext.h"31#include "llvm/IR/Module.h"32#include "llvm/IR/Type.h"33#include "llvm/IR/Value.h"34#include "llvm/IR/Verifier.h"35#include "llvm/Support/Casting.h"36#include "llvm/Support/CommandLine.h"37#include "llvm/Support/ErrorHandling.h"38#include "llvm/Support/FileSystem.h"39#include "llvm/Support/InitLLVM.h"40#include "llvm/Support/ToolOutputFile.h"41#include "llvm/Support/WithColor.h"42#include "llvm/Support/raw_ostream.h"43#include <cassert>44#include <cstddef>45#include <cstdint>46#include <memory>47#include <string>48#include <system_error>49#include <vector>50 51namespace llvm {52 53static cl::OptionCategory StressCategory("Stress Options");54 55static cl::opt<unsigned> SeedCL("seed", cl::desc("Seed used for randomness"),56 cl::init(0), cl::cat(StressCategory));57 58static cl::opt<unsigned> SizeCL(59 "size",60 cl::desc("The estimated size of the generated function (# of instrs)"),61 cl::init(100), cl::cat(StressCategory));62 63static cl::opt<std::string> OutputFilename("o",64 cl::desc("Override output filename"),65 cl::value_desc("filename"),66 cl::cat(StressCategory));67 68static cl::list<StringRef> AdditionalScalarTypes(69 "types", cl::CommaSeparated,70 cl::desc("Additional IR scalar types "71 "(always includes i1, i8, i16, i32, i64, float and double)"));72 73static cl::opt<bool> EnableScalableVectors(74 "enable-scalable-vectors",75 cl::desc("Generate IR involving scalable vector types"),76 cl::init(false), cl::cat(StressCategory));77 78 79namespace {80 81/// A utility class to provide a pseudo-random number generator which is82/// the same across all platforms. This is somewhat close to the libc83/// implementation. Note: This is not a cryptographically secure pseudorandom84/// number generator.85class Random {86public:87 /// C'tor88 Random(unsigned _seed):Seed(_seed) {}89 90 /// Return a random integer, up to a91 /// maximum of 2**19 - 1.92 uint32_t Rand() {93 uint32_t Val = Seed + 0x000b07a1;94 Seed = (Val * 0x3c7c0ac1);95 // Only lowest 19 bits are random-ish.96 return Seed & 0x7ffff;97 }98 99 /// Return a random 64 bit integer.100 uint64_t Rand64() {101 uint64_t Val = Rand() & 0xffff;102 Val |= uint64_t(Rand() & 0xffff) << 16;103 Val |= uint64_t(Rand() & 0xffff) << 32;104 Val |= uint64_t(Rand() & 0xffff) << 48;105 return Val;106 }107 108 /// Rand operator for STL algorithms.109 ptrdiff_t operator()(ptrdiff_t y) {110 return Rand64() % y;111 }112 113 /// Make this like a C++11 random device114 using result_type = uint32_t ;115 116 static constexpr result_type min() { return 0; }117 static constexpr result_type max() { return 0x7ffff; }118 119 uint32_t operator()() {120 uint32_t Val = Rand();121 assert(Val <= max() && "Random value out of range");122 return Val;123 }124 125private:126 unsigned Seed;127};128 129/// Generate an empty function with a default argument list.130Function *GenEmptyFunction(Module *M) {131 // Define a few arguments132 LLVMContext &Context = M->getContext();133 Type* ArgsTy[] = {134 PointerType::get(Context, 0),135 PointerType::get(Context, 0),136 PointerType::get(Context, 0),137 Type::getInt32Ty(Context),138 Type::getInt64Ty(Context),139 Type::getInt8Ty(Context)140 };141 142 auto *FuncTy = FunctionType::get(Type::getVoidTy(Context), ArgsTy, false);143 // Pick a unique name to describe the input parameters144 Twine Name = "autogen_SD" + Twine{SeedCL};145 auto *Func = Function::Create(FuncTy, GlobalValue::ExternalLinkage, Name, M);146 Func->setCallingConv(CallingConv::C);147 return Func;148}149 150/// A base class, implementing utilities needed for151/// modifying and adding new random instructions.152struct Modifier {153 /// Used to store the randomly generated values.154 using PieceTable = std::vector<Value *>;155 156public:157 /// C'tor158 Modifier(BasicBlock *Block, PieceTable *PT, Random *R)159 : BB(Block), PT(PT), Ran(R), Context(BB->getContext()) {160 ScalarTypes.assign({Type::getInt1Ty(Context), Type::getInt8Ty(Context),161 Type::getInt16Ty(Context), Type::getInt32Ty(Context),162 Type::getInt64Ty(Context), Type::getFloatTy(Context),163 Type::getDoubleTy(Context)});164 165 for (auto &Arg : AdditionalScalarTypes) {166 Type *Ty = nullptr;167 if (Arg == "half")168 Ty = Type::getHalfTy(Context);169 else if (Arg == "fp128")170 Ty = Type::getFP128Ty(Context);171 else if (Arg == "x86_fp80")172 Ty = Type::getX86_FP80Ty(Context);173 else if (Arg == "ppc_fp128")174 Ty = Type::getPPC_FP128Ty(Context);175 else if (Arg.starts_with("i")) {176 unsigned N = 0;177 Arg.drop_front().getAsInteger(10, N);178 if (N > 0)179 Ty = Type::getIntNTy(Context, N);180 }181 if (!Ty) {182 errs() << "Invalid IR scalar type: '" << Arg << "'!\n";183 exit(1);184 }185 186 ScalarTypes.push_back(Ty);187 }188 }189 190 /// virtual D'tor to silence warnings.191 virtual ~Modifier() = default;192 193 /// Add a new instruction.194 virtual void Act() = 0;195 196 /// Add N new instructions,197 virtual void ActN(unsigned n) {198 for (unsigned i=0; i<n; ++i)199 Act();200 }201 202protected:203 /// Return a random integer.204 uint32_t getRandom() {205 return Ran->Rand();206 }207 208 /// Return a random value from the list of known values.209 Value *getRandomVal() {210 assert(PT->size());211 return PT->at(getRandom() % PT->size());212 }213 214 Constant *getRandomConstant(Type *Tp) {215 if (Tp->isIntegerTy()) {216 if (getRandom() & 1)217 return ConstantInt::getAllOnesValue(Tp);218 return ConstantInt::getNullValue(Tp);219 } else if (Tp->isFloatingPointTy()) {220 if (getRandom() & 1)221 return ConstantFP::getAllOnesValue(Tp);222 return ConstantFP::getZero(Tp);223 }224 return UndefValue::get(Tp);225 }226 227 /// Return a random value with a known type.228 Value *getRandomValue(Type *Tp) {229 unsigned index = getRandom();230 for (unsigned i=0; i<PT->size(); ++i) {231 Value *V = PT->at((index + i) % PT->size());232 if (V->getType() == Tp)233 return V;234 }235 236 // If the requested type was not found, generate a constant value.237 if (Tp->isIntegerTy()) {238 if (getRandom() & 1)239 return ConstantInt::getAllOnesValue(Tp);240 return ConstantInt::getNullValue(Tp);241 } else if (Tp->isFloatingPointTy()) {242 if (getRandom() & 1)243 return ConstantFP::getAllOnesValue(Tp);244 return ConstantFP::getZero(Tp);245 } else if (auto *VTp = dyn_cast<FixedVectorType>(Tp)) {246 std::vector<Constant*> TempValues;247 TempValues.reserve(VTp->getNumElements());248 for (unsigned i = 0; i < VTp->getNumElements(); ++i)249 TempValues.push_back(getRandomConstant(VTp->getScalarType()));250 251 ArrayRef<Constant*> VectorValue(TempValues);252 return ConstantVector::get(VectorValue);253 }254 255 return UndefValue::get(Tp);256 }257 258 /// Return a random value of any pointer type.259 Value *getRandomPointerValue() {260 unsigned index = getRandom();261 for (unsigned i=0; i<PT->size(); ++i) {262 Value *V = PT->at((index + i) % PT->size());263 if (V->getType()->isPointerTy())264 return V;265 }266 return UndefValue::get(PointerType::get(Context, 0));267 }268 269 /// Return a random value of any vector type.270 Value *getRandomVectorValue() {271 unsigned index = getRandom();272 for (unsigned i=0; i<PT->size(); ++i) {273 Value *V = PT->at((index + i) % PT->size());274 if (V->getType()->isVectorTy())275 return V;276 }277 return UndefValue::get(pickVectorType());278 }279 280 /// Pick a random type.281 Type *pickType() {282 return (getRandom() & 1) ? pickVectorType() : pickScalarType();283 }284 285 /// Pick a random vector type.286 Type *pickVectorType(VectorType *VTy = nullptr) {287 288 Type *Ty = pickScalarType();289 290 if (VTy)291 return VectorType::get(Ty, VTy->getElementCount());292 293 // Select either fixed length or scalable vectors with 50% probability294 // (only if scalable vectors are enabled)295 bool Scalable = EnableScalableVectors && getRandom() & 1;296 297 // Pick a random vector width in the range 2**0 to 2**4.298 // by adding two randoms we are generating a normal-like distribution299 // around 2**3.300 unsigned width = 1<<((getRandom() % 3) + (getRandom() % 3));301 return VectorType::get(Ty, width, Scalable);302 }303 304 /// Pick a random scalar type.305 Type *pickScalarType() {306 return ScalarTypes[getRandom() % ScalarTypes.size()];307 }308 309 /// Basic block to populate310 BasicBlock *BB;311 312 /// Value table313 PieceTable *PT;314 315 /// Random number generator316 Random *Ran;317 318 /// Context319 LLVMContext &Context;320 321 std::vector<Type *> ScalarTypes;322};323 324struct LoadModifier: public Modifier {325 LoadModifier(BasicBlock *BB, PieceTable *PT, Random *R)326 : Modifier(BB, PT, R) {}327 328 void Act() override {329 // Try to use predefined pointers. If non-exist, use undef pointer value;330 Value *Ptr = getRandomPointerValue();331 Type *Ty = pickType();332 Value *V = new LoadInst(Ty, Ptr, "L", BB->getTerminator()->getIterator());333 PT->push_back(V);334 }335};336 337struct StoreModifier: public Modifier {338 StoreModifier(BasicBlock *BB, PieceTable *PT, Random *R)339 : Modifier(BB, PT, R) {}340 341 void Act() override {342 // Try to use predefined pointers. If non-exist, use undef pointer value;343 Value *Ptr = getRandomPointerValue();344 Type *ValTy = pickType();345 346 // Do not store vectors of i1s because they are unsupported347 // by the codegen.348 if (ValTy->isVectorTy() && ValTy->getScalarSizeInBits() == 1)349 return;350 351 Value *Val = getRandomValue(ValTy);352 new StoreInst(Val, Ptr, BB->getTerminator()->getIterator());353 }354};355 356struct BinModifier: public Modifier {357 BinModifier(BasicBlock *BB, PieceTable *PT, Random *R)358 : Modifier(BB, PT, R) {}359 360 void Act() override {361 Value *Val0 = getRandomVal();362 Value *Val1 = getRandomValue(Val0->getType());363 364 // Don't handle pointer types.365 if (Val0->getType()->isPointerTy() ||366 Val1->getType()->isPointerTy())367 return;368 369 // Don't handle i1 types.370 if (Val0->getType()->getScalarSizeInBits() == 1)371 return;372 373 bool isFloat = Val0->getType()->getScalarType()->isFloatingPointTy();374 Instruction* Term = BB->getTerminator();375 unsigned R = getRandom() % (isFloat ? 7 : 13);376 Instruction::BinaryOps Op;377 378 switch (R) {379 default: llvm_unreachable("Invalid BinOp");380 case 0:{Op = (isFloat?Instruction::FAdd : Instruction::Add); break; }381 case 1:{Op = (isFloat?Instruction::FSub : Instruction::Sub); break; }382 case 2:{Op = (isFloat?Instruction::FMul : Instruction::Mul); break; }383 case 3:{Op = (isFloat?Instruction::FDiv : Instruction::SDiv); break; }384 case 4:{Op = (isFloat?Instruction::FDiv : Instruction::UDiv); break; }385 case 5:{Op = (isFloat?Instruction::FRem : Instruction::SRem); break; }386 case 6:{Op = (isFloat?Instruction::FRem : Instruction::URem); break; }387 case 7: {Op = Instruction::Shl; break; }388 case 8: {Op = Instruction::LShr; break; }389 case 9: {Op = Instruction::AShr; break; }390 case 10:{Op = Instruction::And; break; }391 case 11:{Op = Instruction::Or; break; }392 case 12:{Op = Instruction::Xor; break; }393 }394 395 PT->push_back(396 BinaryOperator::Create(Op, Val0, Val1, "B", Term->getIterator()));397 }398};399 400/// Generate constant values.401struct ConstModifier: public Modifier {402 ConstModifier(BasicBlock *BB, PieceTable *PT, Random *R)403 : Modifier(BB, PT, R) {}404 405 void Act() override {406 Type *Ty = pickType();407 408 if (Ty->isVectorTy()) {409 switch (getRandom() % 2) {410 case 0: if (Ty->isIntOrIntVectorTy())411 return PT->push_back(ConstantVector::getAllOnesValue(Ty));412 break;413 case 1: if (Ty->isIntOrIntVectorTy())414 return PT->push_back(ConstantVector::getNullValue(Ty));415 }416 }417 418 if (Ty->isFloatingPointTy()) {419 // Generate 128 random bits, the size of the (currently)420 // largest floating-point types.421 uint64_t RandomBits[2];422 for (unsigned i = 0; i < 2; ++i)423 RandomBits[i] = Ran->Rand64();424 425 APInt RandomInt(Ty->getPrimitiveSizeInBits(), ArrayRef(RandomBits));426 APFloat RandomFloat(Ty->getFltSemantics(), RandomInt);427 428 if (getRandom() & 1)429 return PT->push_back(ConstantFP::getZero(Ty));430 return PT->push_back(ConstantFP::get(Ty->getContext(), RandomFloat));431 }432 433 if (Ty->isIntegerTy()) {434 switch (getRandom() % 7) {435 case 0:436 return PT->push_back(ConstantInt::get(437 Ty, APInt::getAllOnes(Ty->getPrimitiveSizeInBits())));438 case 1:439 return PT->push_back(440 ConstantInt::get(Ty, APInt::getZero(Ty->getPrimitiveSizeInBits())));441 case 2:442 case 3:443 case 4:444 case 5:445 case 6:446 PT->push_back(ConstantInt::get(Ty, getRandom()));447 }448 }449 }450};451 452struct AllocaModifier: public Modifier {453 AllocaModifier(BasicBlock *BB, PieceTable *PT, Random *R)454 : Modifier(BB, PT, R) {}455 456 void Act() override {457 Type *Tp = pickType();458 const DataLayout &DL = BB->getDataLayout();459 PT->push_back(new AllocaInst(Tp, DL.getAllocaAddrSpace(), "A",460 BB->getFirstNonPHIIt()));461 }462};463 464struct ExtractElementModifier: public Modifier {465 ExtractElementModifier(BasicBlock *BB, PieceTable *PT, Random *R)466 : Modifier(BB, PT, R) {}467 468 void Act() override {469 Value *Val0 = getRandomVectorValue();470 Value *V = ExtractElementInst::Create(471 Val0, getRandomValue(Type::getInt32Ty(BB->getContext())), "E",472 BB->getTerminator()->getIterator());473 return PT->push_back(V);474 }475};476 477struct ShuffModifier: public Modifier {478 ShuffModifier(BasicBlock *BB, PieceTable *PT, Random *R)479 : Modifier(BB, PT, R) {}480 481 void Act() override {482 Value *Val0 = getRandomVectorValue();483 Value *Val1 = getRandomValue(Val0->getType());484 485 // Can't express arbitrary shufflevectors for scalable vectors486 if (isa<ScalableVectorType>(Val0->getType()))487 return;488 489 unsigned Width = cast<FixedVectorType>(Val0->getType())->getNumElements();490 std::vector<Constant*> Idxs;491 492 Type *I32 = Type::getInt32Ty(BB->getContext());493 for (unsigned i=0; i<Width; ++i) {494 Constant *CI = ConstantInt::get(I32, getRandom() % (Width*2));495 // Pick some undef values.496 if (!(getRandom() % 5))497 CI = UndefValue::get(I32);498 Idxs.push_back(CI);499 }500 501 Constant *Mask = ConstantVector::get(Idxs);502 503 Value *V = new ShuffleVectorInst(Val0, Val1, Mask, "Shuff",504 BB->getTerminator()->getIterator());505 PT->push_back(V);506 }507};508 509struct InsertElementModifier: public Modifier {510 InsertElementModifier(BasicBlock *BB, PieceTable *PT, Random *R)511 : Modifier(BB, PT, R) {}512 513 void Act() override {514 Value *Val0 = getRandomVectorValue();515 Value *Val1 = getRandomValue(Val0->getType()->getScalarType());516 517 Value *V = InsertElementInst::Create(518 Val0, Val1, getRandomValue(Type::getInt32Ty(BB->getContext())), "I",519 BB->getTerminator()->getIterator());520 return PT->push_back(V);521 }522};523 524struct CastModifier: public Modifier {525 CastModifier(BasicBlock *BB, PieceTable *PT, Random *R)526 : Modifier(BB, PT, R) {}527 528 void Act() override {529 Value *V = getRandomVal();530 Type *VTy = V->getType();531 Type *DestTy = pickScalarType();532 533 // Handle vector casts vectors.534 if (VTy->isVectorTy())535 DestTy = pickVectorType(cast<VectorType>(VTy));536 537 // no need to cast.538 if (VTy == DestTy) return;539 540 // Pointers:541 if (VTy->isPointerTy()) {542 if (!DestTy->isPointerTy())543 DestTy = PointerType::get(Context, 0);544 return PT->push_back(545 new BitCastInst(V, DestTy, "PC", BB->getTerminator()->getIterator()));546 }547 548 unsigned VSize = VTy->getScalarType()->getPrimitiveSizeInBits();549 unsigned DestSize = DestTy->getScalarType()->getPrimitiveSizeInBits();550 551 // Generate lots of bitcasts.552 if ((getRandom() & 1) && VSize == DestSize) {553 return PT->push_back(554 new BitCastInst(V, DestTy, "BC", BB->getTerminator()->getIterator()));555 }556 557 // Both types are integers:558 if (VTy->isIntOrIntVectorTy() && DestTy->isIntOrIntVectorTy()) {559 if (VSize > DestSize) {560 return PT->push_back(561 new TruncInst(V, DestTy, "Tr", BB->getTerminator()->getIterator()));562 } else {563 assert(VSize < DestSize && "Different int types with the same size?");564 if (getRandom() & 1)565 return PT->push_back(new ZExtInst(566 V, DestTy, "ZE", BB->getTerminator()->getIterator()));567 return PT->push_back(568 new SExtInst(V, DestTy, "Se", BB->getTerminator()->getIterator()));569 }570 }571 572 // Fp to int.573 if (VTy->isFPOrFPVectorTy() && DestTy->isIntOrIntVectorTy()) {574 if (getRandom() & 1)575 return PT->push_back(new FPToSIInst(576 V, DestTy, "FC", BB->getTerminator()->getIterator()));577 return PT->push_back(578 new FPToUIInst(V, DestTy, "FC", BB->getTerminator()->getIterator()));579 }580 581 // Int to fp.582 if (VTy->isIntOrIntVectorTy() && DestTy->isFPOrFPVectorTy()) {583 if (getRandom() & 1)584 return PT->push_back(new SIToFPInst(585 V, DestTy, "FC", BB->getTerminator()->getIterator()));586 return PT->push_back(587 new UIToFPInst(V, DestTy, "FC", BB->getTerminator()->getIterator()));588 }589 590 // Both floats.591 if (VTy->isFPOrFPVectorTy() && DestTy->isFPOrFPVectorTy()) {592 if (VSize > DestSize) {593 return PT->push_back(new FPTruncInst(594 V, DestTy, "Tr", BB->getTerminator()->getIterator()));595 } else if (VSize < DestSize) {596 return PT->push_back(597 new FPExtInst(V, DestTy, "ZE", BB->getTerminator()->getIterator()));598 }599 // If VSize == DestSize, then the two types must be fp128 and ppc_fp128,600 // for which there is no defined conversion. So do nothing.601 }602 }603};604 605struct SelectModifier: public Modifier {606 SelectModifier(BasicBlock *BB, PieceTable *PT, Random *R)607 : Modifier(BB, PT, R) {}608 609 void Act() override {610 // Try a bunch of different select configuration until a valid one is found.611 Value *Val0 = getRandomVal();612 Value *Val1 = getRandomValue(Val0->getType());613 614 Type *CondTy = Type::getInt1Ty(Context);615 616 // If the value type is a vector, and we allow vector select, then in 50%617 // of the cases generate a vector select.618 if (auto *VTy = dyn_cast<VectorType>(Val0->getType()))619 if (getRandom() & 1)620 CondTy = VectorType::get(CondTy, VTy->getElementCount());621 622 Value *Cond = getRandomValue(CondTy);623 Value *V = SelectInst::Create(Cond, Val0, Val1, "Sl",624 BB->getTerminator()->getIterator());625 return PT->push_back(V);626 }627};628 629struct CmpModifier: public Modifier {630 CmpModifier(BasicBlock *BB, PieceTable *PT, Random *R)631 : Modifier(BB, PT, R) {}632 633 void Act() override {634 Value *Val0 = getRandomVal();635 Value *Val1 = getRandomValue(Val0->getType());636 637 if (Val0->getType()->isPointerTy()) return;638 bool fp = Val0->getType()->getScalarType()->isFloatingPointTy();639 640 int op;641 if (fp) {642 op = getRandom() %643 (CmpInst::LAST_FCMP_PREDICATE - CmpInst::FIRST_FCMP_PREDICATE) +644 CmpInst::FIRST_FCMP_PREDICATE;645 } else {646 op = getRandom() %647 (CmpInst::LAST_ICMP_PREDICATE - CmpInst::FIRST_ICMP_PREDICATE) +648 CmpInst::FIRST_ICMP_PREDICATE;649 }650 651 Value *V = CmpInst::Create(fp ? Instruction::FCmp : Instruction::ICmp,652 (CmpInst::Predicate)op, Val0, Val1, "Cmp",653 BB->getTerminator()->getIterator());654 return PT->push_back(V);655 }656};657 658} // end anonymous namespace659 660static void FillFunction(Function *F, Random &R) {661 // Create a legal entry block.662 BasicBlock *BB = BasicBlock::Create(F->getContext(), "BB", F);663 ReturnInst::Create(F->getContext(), BB);664 665 // Create the value table.666 Modifier::PieceTable PT;667 668 // Consider arguments as legal values.669 for (auto &arg : F->args())670 PT.push_back(&arg);671 672 // List of modifiers which add new random instructions.673 std::vector<std::unique_ptr<Modifier>> Modifiers;674 Modifiers.emplace_back(new LoadModifier(BB, &PT, &R));675 Modifiers.emplace_back(new StoreModifier(BB, &PT, &R));676 auto SM = Modifiers.back().get();677 Modifiers.emplace_back(new ExtractElementModifier(BB, &PT, &R));678 Modifiers.emplace_back(new ShuffModifier(BB, &PT, &R));679 Modifiers.emplace_back(new InsertElementModifier(BB, &PT, &R));680 Modifiers.emplace_back(new BinModifier(BB, &PT, &R));681 Modifiers.emplace_back(new CastModifier(BB, &PT, &R));682 Modifiers.emplace_back(new SelectModifier(BB, &PT, &R));683 Modifiers.emplace_back(new CmpModifier(BB, &PT, &R));684 685 // Generate the random instructions686 AllocaModifier{BB, &PT, &R}.ActN(5); // Throw in a few allocas687 ConstModifier{BB, &PT, &R}.ActN(40); // Throw in a few constants688 689 for (unsigned i = 0; i < SizeCL / Modifiers.size(); ++i)690 for (auto &Mod : Modifiers)691 Mod->Act();692 693 SM->ActN(5); // Throw in a few stores.694}695 696static void IntroduceControlFlow(Function *F, Random &R) {697 std::vector<Instruction*> BoolInst;698 for (auto &Instr : F->front()) {699 if (Instr.getType() == IntegerType::getInt1Ty(F->getContext()))700 BoolInst.push_back(&Instr);701 }702 703 llvm::shuffle(BoolInst.begin(), BoolInst.end(), R);704 705 for (auto *Instr : BoolInst) {706 BasicBlock *Curr = Instr->getParent();707 BasicBlock::iterator Loc = Instr->getIterator();708 BasicBlock *Next = Curr->splitBasicBlock(Loc, "CF");709 Instr->moveBefore(Curr->getTerminator()->getIterator());710 if (Curr != &F->getEntryBlock()) {711 BranchInst::Create(Curr, Next, Instr,712 Curr->getTerminator()->getIterator());713 Curr->getTerminator()->eraseFromParent();714 }715 }716}717 718} // end namespace llvm719 720int main(int argc, char **argv) {721 using namespace llvm;722 723 InitLLVM X(argc, argv);724 cl::HideUnrelatedOptions({&StressCategory, &getColorCategory()});725 cl::ParseCommandLineOptions(argc, argv, "llvm codegen stress-tester\n");726 727 LLVMContext Context;728 auto M = std::make_unique<Module>("/tmp/autogen.bc", Context);729 Function *F = GenEmptyFunction(M.get());730 731 // Pick an initial seed value732 Random R(SeedCL);733 // Generate lots of random instructions inside a single basic block.734 FillFunction(F, R);735 // Break the basic block into many loops.736 IntroduceControlFlow(F, R);737 738 // Figure out what stream we are supposed to write to...739 std::unique_ptr<ToolOutputFile> Out;740 // Default to standard output.741 if (OutputFilename.empty())742 OutputFilename = "-";743 744 std::error_code EC;745 Out.reset(new ToolOutputFile(OutputFilename, EC, sys::fs::OF_None));746 if (EC) {747 errs() << EC.message() << '\n';748 return 1;749 }750 751 // Check that the generated module is accepted by the verifier.752 if (verifyModule(*M.get(), &Out->os()))753 report_fatal_error("Broken module found, compilation aborted!");754 755 // Output textual IR.756 M->print(Out->os(), nullptr);757 758 Out->keep();759 760 return 0;761}762