1 //===-- llvm-stress.cpp - Generate random LL files to stress-test LLVM ----===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This program is a utility that generates random .ll files to stress-test
11 // different components in LLVM.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Analysis/CallGraphSCCPass.h"
16 #include "llvm/IR/Constants.h"
17 #include "llvm/IR/IRPrintingPasses.h"
18 #include "llvm/IR/Instruction.h"
19 #include "llvm/IR/LLVMContext.h"
20 #include "llvm/IR/LegacyPassNameParser.h"
21 #include "llvm/IR/Module.h"
22 #include "llvm/IR/Verifier.h"
23 #include "llvm/IR/LegacyPassManager.h"
24 #include "llvm/Support/Debug.h"
25 #include "llvm/Support/FileSystem.h"
26 #include "llvm/Support/ManagedStatic.h"
27 #include "llvm/Support/PluginLoader.h"
28 #include "llvm/Support/PrettyStackTrace.h"
29 #include "llvm/Support/ToolOutputFile.h"
36 static cl::opt<unsigned> SeedCL("seed",
37 cl::desc("Seed used for randomness"), cl::init(0));
38 static cl::opt<unsigned> SizeCL("size",
39 cl::desc("The estimated size of the generated function (# of instrs)"),
41 static cl::opt<std::string>
42 OutputFilename("o", cl::desc("Override output filename"),
43 cl::value_desc("filename"));
45 static cl::opt<bool> GenHalfFloat("generate-half-float",
46 cl::desc("Generate half-length floating-point values"), cl::init(false));
47 static cl::opt<bool> GenX86FP80("generate-x86-fp80",
48 cl::desc("Generate 80-bit X86 floating-point values"), cl::init(false));
49 static cl::opt<bool> GenFP128("generate-fp128",
50 cl::desc("Generate 128-bit floating-point values"), cl::init(false));
51 static cl::opt<bool> GenPPCFP128("generate-ppc-fp128",
52 cl::desc("Generate 128-bit PPC floating-point values"), cl::init(false));
53 static cl::opt<bool> GenX86MMX("generate-x86-mmx",
54 cl::desc("Generate X86 MMX floating-point values"), cl::init(false));
57 /// A utility class to provide a pseudo-random number generator which is
58 /// the same across all platforms. This is somewhat close to the libc
59 /// implementation. Note: This is not a cryptographically secure pseudorandom
64 Random(unsigned _seed):Seed(_seed) {}
66 /// Return a random integer, up to a
67 /// maximum of 2**19 - 1.
69 uint32_t Val = Seed + 0x000b07a1;
70 Seed = (Val * 0x3c7c0ac1);
71 // Only lowest 19 bits are random-ish.
72 return Seed & 0x7ffff;
75 /// Return a random 32 bit integer.
77 uint32_t Val = Rand();
79 return Val | (Rand() << 16);
82 /// Return a random 64 bit integer.
84 uint64_t Val = Rand32();
85 return Val | (uint64_t(Rand32()) << 32);
88 /// Rand operator for STL algorithms.
89 ptrdiff_t operator()(ptrdiff_t y) {
97 /// Generate an empty function with a default argument list.
98 Function *GenEmptyFunction(Module *M) {
100 std::vector<Type*> ArgsTy;
101 // Define a few arguments
102 LLVMContext &Context = M->getContext();
103 ArgsTy.push_back(PointerType::get(IntegerType::getInt8Ty(Context), 0));
104 ArgsTy.push_back(PointerType::get(IntegerType::getInt32Ty(Context), 0));
105 ArgsTy.push_back(PointerType::get(IntegerType::getInt64Ty(Context), 0));
106 ArgsTy.push_back(IntegerType::getInt32Ty(Context));
107 ArgsTy.push_back(IntegerType::getInt64Ty(Context));
108 ArgsTy.push_back(IntegerType::getInt8Ty(Context));
110 FunctionType *FuncTy = FunctionType::get(Type::getVoidTy(Context), ArgsTy, 0);
111 // Pick a unique name to describe the input parameters
112 std::stringstream ss;
113 ss<<"autogen_SD"<<SeedCL;
114 Function *Func = Function::Create(FuncTy, GlobalValue::ExternalLinkage,
117 Func->setCallingConv(CallingConv::C);
121 /// A base class, implementing utilities needed for
122 /// modifying and adding new random instructions.
124 /// Used to store the randomly generated values.
125 typedef std::vector<Value*> PieceTable;
129 Modifier(BasicBlock *Block, PieceTable *PT, Random *R):
130 BB(Block),PT(PT),Ran(R),Context(BB->getContext()) {}
132 /// virtual D'tor to silence warnings.
133 virtual ~Modifier() {}
135 /// Add a new instruction.
136 virtual void Act() = 0;
137 /// Add N new instructions,
138 virtual void ActN(unsigned n) {
139 for (unsigned i=0; i<n; ++i)
144 /// Return a random value from the list of known values.
145 Value *getRandomVal() {
147 return PT->at(Ran->Rand() % PT->size());
150 Constant *getRandomConstant(Type *Tp) {
151 if (Tp->isIntegerTy()) {
153 return ConstantInt::getAllOnesValue(Tp);
154 return ConstantInt::getNullValue(Tp);
155 } else if (Tp->isFloatingPointTy()) {
157 return ConstantFP::getAllOnesValue(Tp);
158 return ConstantFP::getNullValue(Tp);
160 return UndefValue::get(Tp);
163 /// Return a random value with a known type.
164 Value *getRandomValue(Type *Tp) {
165 unsigned index = Ran->Rand();
166 for (unsigned i=0; i<PT->size(); ++i) {
167 Value *V = PT->at((index + i) % PT->size());
168 if (V->getType() == Tp)
172 // If the requested type was not found, generate a constant value.
173 if (Tp->isIntegerTy()) {
175 return ConstantInt::getAllOnesValue(Tp);
176 return ConstantInt::getNullValue(Tp);
177 } else if (Tp->isFloatingPointTy()) {
179 return ConstantFP::getAllOnesValue(Tp);
180 return ConstantFP::getNullValue(Tp);
181 } else if (Tp->isVectorTy()) {
182 VectorType *VTp = cast<VectorType>(Tp);
184 std::vector<Constant*> TempValues;
185 TempValues.reserve(VTp->getNumElements());
186 for (unsigned i = 0; i < VTp->getNumElements(); ++i)
187 TempValues.push_back(getRandomConstant(VTp->getScalarType()));
189 ArrayRef<Constant*> VectorValue(TempValues);
190 return ConstantVector::get(VectorValue);
193 return UndefValue::get(Tp);
196 /// Return a random value of any pointer type.
197 Value *getRandomPointerValue() {
198 unsigned index = Ran->Rand();
199 for (unsigned i=0; i<PT->size(); ++i) {
200 Value *V = PT->at((index + i) % PT->size());
201 if (V->getType()->isPointerTy())
204 return UndefValue::get(pickPointerType());
207 /// Return a random value of any vector type.
208 Value *getRandomVectorValue() {
209 unsigned index = Ran->Rand();
210 for (unsigned i=0; i<PT->size(); ++i) {
211 Value *V = PT->at((index + i) % PT->size());
212 if (V->getType()->isVectorTy())
215 return UndefValue::get(pickVectorType());
218 /// Pick a random type.
220 return (Ran->Rand() & 1 ? pickVectorType() : pickScalarType());
223 /// Pick a random pointer type.
224 Type *pickPointerType() {
225 Type *Ty = pickType();
226 return PointerType::get(Ty, 0);
229 /// Pick a random vector type.
230 Type *pickVectorType(unsigned len = (unsigned)-1) {
231 // Pick a random vector width in the range 2**0 to 2**4.
232 // by adding two randoms we are generating a normal-like distribution
234 unsigned width = 1<<((Ran->Rand() % 3) + (Ran->Rand() % 3));
237 // Vectors of x86mmx are illegal; keep trying till we get something else.
239 Ty = pickScalarType();
240 } while (Ty->isX86_MMXTy());
242 if (len != (unsigned)-1)
244 return VectorType::get(Ty, width);
247 /// Pick a random scalar type.
248 Type *pickScalarType() {
251 switch (Ran->Rand() % 30) {
252 case 0: t = Type::getInt1Ty(Context); break;
253 case 1: t = Type::getInt8Ty(Context); break;
254 case 2: t = Type::getInt16Ty(Context); break;
256 case 5: t = Type::getFloatTy(Context); break;
258 case 8: t = Type::getDoubleTy(Context); break;
260 case 11: t = Type::getInt32Ty(Context); break;
262 case 14: t = Type::getInt64Ty(Context); break;
264 case 17: if (GenHalfFloat) t = Type::getHalfTy(Context); break;
266 case 20: if (GenX86FP80) t = Type::getX86_FP80Ty(Context); break;
268 case 23: if (GenFP128) t = Type::getFP128Ty(Context); break;
270 case 26: if (GenPPCFP128) t = Type::getPPC_FP128Ty(Context); break;
272 case 29: if (GenX86MMX) t = Type::getX86_MMXTy(Context); break;
273 default: llvm_unreachable("Invalid scalar value");
275 } while (t == nullptr);
280 /// Basic block to populate
284 /// Random number generator
287 LLVMContext &Context;
290 struct LoadModifier: public Modifier {
291 LoadModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
292 void Act() override {
293 // Try to use predefined pointers. If non-exist, use undef pointer value;
294 Value *Ptr = getRandomPointerValue();
295 Value *V = new LoadInst(Ptr, "L", BB->getTerminator());
300 struct StoreModifier: public Modifier {
301 StoreModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
302 void Act() override {
303 // Try to use predefined pointers. If non-exist, use undef pointer value;
304 Value *Ptr = getRandomPointerValue();
305 Type *Tp = Ptr->getType();
306 Value *Val = getRandomValue(Tp->getContainedType(0));
307 Type *ValTy = Val->getType();
309 // Do not store vectors of i1s because they are unsupported
311 if (ValTy->isVectorTy() && ValTy->getScalarSizeInBits() == 1)
314 new StoreInst(Val, Ptr, BB->getTerminator());
318 struct BinModifier: public Modifier {
319 BinModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
321 void Act() override {
322 Value *Val0 = getRandomVal();
323 Value *Val1 = getRandomValue(Val0->getType());
325 // Don't handle pointer types.
326 if (Val0->getType()->isPointerTy() ||
327 Val1->getType()->isPointerTy())
330 // Don't handle i1 types.
331 if (Val0->getType()->getScalarSizeInBits() == 1)
335 bool isFloat = Val0->getType()->getScalarType()->isFloatingPointTy();
336 Instruction* Term = BB->getTerminator();
337 unsigned R = Ran->Rand() % (isFloat ? 7 : 13);
338 Instruction::BinaryOps Op;
341 default: llvm_unreachable("Invalid BinOp");
342 case 0:{Op = (isFloat?Instruction::FAdd : Instruction::Add); break; }
343 case 1:{Op = (isFloat?Instruction::FSub : Instruction::Sub); break; }
344 case 2:{Op = (isFloat?Instruction::FMul : Instruction::Mul); break; }
345 case 3:{Op = (isFloat?Instruction::FDiv : Instruction::SDiv); break; }
346 case 4:{Op = (isFloat?Instruction::FDiv : Instruction::UDiv); break; }
347 case 5:{Op = (isFloat?Instruction::FRem : Instruction::SRem); break; }
348 case 6:{Op = (isFloat?Instruction::FRem : Instruction::URem); break; }
349 case 7: {Op = Instruction::Shl; break; }
350 case 8: {Op = Instruction::LShr; break; }
351 case 9: {Op = Instruction::AShr; break; }
352 case 10:{Op = Instruction::And; break; }
353 case 11:{Op = Instruction::Or; break; }
354 case 12:{Op = Instruction::Xor; break; }
357 PT->push_back(BinaryOperator::Create(Op, Val0, Val1, "B", Term));
361 /// Generate constant values.
362 struct ConstModifier: public Modifier {
363 ConstModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
364 void Act() override {
365 Type *Ty = pickType();
367 if (Ty->isVectorTy()) {
368 switch (Ran->Rand() % 2) {
369 case 0: if (Ty->getScalarType()->isIntegerTy())
370 return PT->push_back(ConstantVector::getAllOnesValue(Ty));
371 case 1: if (Ty->getScalarType()->isIntegerTy())
372 return PT->push_back(ConstantVector::getNullValue(Ty));
376 if (Ty->isFloatingPointTy()) {
377 // Generate 128 random bits, the size of the (currently)
378 // largest floating-point types.
379 uint64_t RandomBits[2];
380 for (unsigned i = 0; i < 2; ++i)
381 RandomBits[i] = Ran->Rand64();
383 APInt RandomInt(Ty->getPrimitiveSizeInBits(), makeArrayRef(RandomBits));
384 APFloat RandomFloat(Ty->getFltSemantics(), RandomInt);
387 return PT->push_back(ConstantFP::getNullValue(Ty));
388 return PT->push_back(ConstantFP::get(Ty->getContext(), RandomFloat));
391 if (Ty->isIntegerTy()) {
392 switch (Ran->Rand() % 7) {
393 case 0: if (Ty->isIntegerTy())
394 return PT->push_back(ConstantInt::get(Ty,
395 APInt::getAllOnesValue(Ty->getPrimitiveSizeInBits())));
396 case 1: if (Ty->isIntegerTy())
397 return PT->push_back(ConstantInt::get(Ty,
398 APInt::getNullValue(Ty->getPrimitiveSizeInBits())));
399 case 2: case 3: case 4: case 5:
400 case 6: if (Ty->isIntegerTy())
401 PT->push_back(ConstantInt::get(Ty, Ran->Rand()));
408 struct AllocaModifier: public Modifier {
409 AllocaModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R){}
411 void Act() override {
412 Type *Tp = pickType();
413 PT->push_back(new AllocaInst(Tp, "A", BB->getFirstNonPHI()));
417 struct ExtractElementModifier: public Modifier {
418 ExtractElementModifier(BasicBlock *BB, PieceTable *PT, Random *R):
419 Modifier(BB, PT, R) {}
421 void Act() override {
422 Value *Val0 = getRandomVectorValue();
423 Value *V = ExtractElementInst::Create(Val0,
424 ConstantInt::get(Type::getInt32Ty(BB->getContext()),
425 Ran->Rand() % cast<VectorType>(Val0->getType())->getNumElements()),
426 "E", BB->getTerminator());
427 return PT->push_back(V);
431 struct ShuffModifier: public Modifier {
432 ShuffModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
433 void Act() override {
435 Value *Val0 = getRandomVectorValue();
436 Value *Val1 = getRandomValue(Val0->getType());
438 unsigned Width = cast<VectorType>(Val0->getType())->getNumElements();
439 std::vector<Constant*> Idxs;
441 Type *I32 = Type::getInt32Ty(BB->getContext());
442 for (unsigned i=0; i<Width; ++i) {
443 Constant *CI = ConstantInt::get(I32, Ran->Rand() % (Width*2));
444 // Pick some undef values.
445 if (!(Ran->Rand() % 5))
446 CI = UndefValue::get(I32);
450 Constant *Mask = ConstantVector::get(Idxs);
452 Value *V = new ShuffleVectorInst(Val0, Val1, Mask, "Shuff",
453 BB->getTerminator());
458 struct InsertElementModifier: public Modifier {
459 InsertElementModifier(BasicBlock *BB, PieceTable *PT, Random *R):
460 Modifier(BB, PT, R) {}
462 void Act() override {
463 Value *Val0 = getRandomVectorValue();
464 Value *Val1 = getRandomValue(Val0->getType()->getScalarType());
466 Value *V = InsertElementInst::Create(Val0, Val1,
467 ConstantInt::get(Type::getInt32Ty(BB->getContext()),
468 Ran->Rand() % cast<VectorType>(Val0->getType())->getNumElements()),
469 "I", BB->getTerminator());
470 return PT->push_back(V);
475 struct CastModifier: public Modifier {
476 CastModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
477 void Act() override {
479 Value *V = getRandomVal();
480 Type *VTy = V->getType();
481 Type *DestTy = pickScalarType();
483 // Handle vector casts vectors.
484 if (VTy->isVectorTy()) {
485 VectorType *VecTy = cast<VectorType>(VTy);
486 DestTy = pickVectorType(VecTy->getNumElements());
490 if (VTy == DestTy) return;
493 if (VTy->isPointerTy()) {
494 if (!DestTy->isPointerTy())
495 DestTy = PointerType::get(DestTy, 0);
496 return PT->push_back(
497 new BitCastInst(V, DestTy, "PC", BB->getTerminator()));
500 unsigned VSize = VTy->getScalarType()->getPrimitiveSizeInBits();
501 unsigned DestSize = DestTy->getScalarType()->getPrimitiveSizeInBits();
503 // Generate lots of bitcasts.
504 if ((Ran->Rand() & 1) && VSize == DestSize) {
505 return PT->push_back(
506 new BitCastInst(V, DestTy, "BC", BB->getTerminator()));
509 // Both types are integers:
510 if (VTy->getScalarType()->isIntegerTy() &&
511 DestTy->getScalarType()->isIntegerTy()) {
512 if (VSize > DestSize) {
513 return PT->push_back(
514 new TruncInst(V, DestTy, "Tr", BB->getTerminator()));
516 assert(VSize < DestSize && "Different int types with the same size?");
518 return PT->push_back(
519 new ZExtInst(V, DestTy, "ZE", BB->getTerminator()));
520 return PT->push_back(new SExtInst(V, DestTy, "Se", BB->getTerminator()));
525 if (VTy->getScalarType()->isFloatingPointTy() &&
526 DestTy->getScalarType()->isIntegerTy()) {
528 return PT->push_back(
529 new FPToSIInst(V, DestTy, "FC", BB->getTerminator()));
530 return PT->push_back(new FPToUIInst(V, DestTy, "FC", BB->getTerminator()));
534 if (VTy->getScalarType()->isIntegerTy() &&
535 DestTy->getScalarType()->isFloatingPointTy()) {
537 return PT->push_back(
538 new SIToFPInst(V, DestTy, "FC", BB->getTerminator()));
539 return PT->push_back(new UIToFPInst(V, DestTy, "FC", BB->getTerminator()));
544 if (VTy->getScalarType()->isFloatingPointTy() &&
545 DestTy->getScalarType()->isFloatingPointTy()) {
546 if (VSize > DestSize) {
547 return PT->push_back(
548 new FPTruncInst(V, DestTy, "Tr", BB->getTerminator()));
549 } else if (VSize < DestSize) {
550 return PT->push_back(
551 new FPExtInst(V, DestTy, "ZE", BB->getTerminator()));
553 // If VSize == DestSize, then the two types must be fp128 and ppc_fp128,
554 // for which there is no defined conversion. So do nothing.
560 struct SelectModifier: public Modifier {
561 SelectModifier(BasicBlock *BB, PieceTable *PT, Random *R):
562 Modifier(BB, PT, R) {}
564 void Act() override {
565 // Try a bunch of different select configuration until a valid one is found.
566 Value *Val0 = getRandomVal();
567 Value *Val1 = getRandomValue(Val0->getType());
569 Type *CondTy = Type::getInt1Ty(Context);
571 // If the value type is a vector, and we allow vector select, then in 50%
572 // of the cases generate a vector select.
573 if (Val0->getType()->isVectorTy() && (Ran->Rand() % 1)) {
574 unsigned NumElem = cast<VectorType>(Val0->getType())->getNumElements();
575 CondTy = VectorType::get(CondTy, NumElem);
578 Value *Cond = getRandomValue(CondTy);
579 Value *V = SelectInst::Create(Cond, Val0, Val1, "Sl", BB->getTerminator());
580 return PT->push_back(V);
585 struct CmpModifier: public Modifier {
586 CmpModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
587 void Act() override {
589 Value *Val0 = getRandomVal();
590 Value *Val1 = getRandomValue(Val0->getType());
592 if (Val0->getType()->isPointerTy()) return;
593 bool fp = Val0->getType()->getScalarType()->isFloatingPointTy();
598 (CmpInst::LAST_FCMP_PREDICATE - CmpInst::FIRST_FCMP_PREDICATE) +
599 CmpInst::FIRST_FCMP_PREDICATE;
602 (CmpInst::LAST_ICMP_PREDICATE - CmpInst::FIRST_ICMP_PREDICATE) +
603 CmpInst::FIRST_ICMP_PREDICATE;
606 Value *V = CmpInst::Create(fp ? Instruction::FCmp : Instruction::ICmp,
607 op, Val0, Val1, "Cmp", BB->getTerminator());
608 return PT->push_back(V);
612 } // end anonymous namespace
614 static void FillFunction(Function *F, Random &R) {
615 // Create a legal entry block.
616 BasicBlock *BB = BasicBlock::Create(F->getContext(), "BB", F);
617 ReturnInst::Create(F->getContext(), BB);
619 // Create the value table.
620 Modifier::PieceTable PT;
622 // Consider arguments as legal values.
623 for (Function::arg_iterator it = F->arg_begin(), e = F->arg_end();
627 // List of modifiers which add new random instructions.
628 std::vector<Modifier*> Modifiers;
629 std::unique_ptr<Modifier> LM(new LoadModifier(BB, &PT, &R));
630 std::unique_ptr<Modifier> SM(new StoreModifier(BB, &PT, &R));
631 std::unique_ptr<Modifier> EE(new ExtractElementModifier(BB, &PT, &R));
632 std::unique_ptr<Modifier> SHM(new ShuffModifier(BB, &PT, &R));
633 std::unique_ptr<Modifier> IE(new InsertElementModifier(BB, &PT, &R));
634 std::unique_ptr<Modifier> BM(new BinModifier(BB, &PT, &R));
635 std::unique_ptr<Modifier> CM(new CastModifier(BB, &PT, &R));
636 std::unique_ptr<Modifier> SLM(new SelectModifier(BB, &PT, &R));
637 std::unique_ptr<Modifier> PM(new CmpModifier(BB, &PT, &R));
638 Modifiers.push_back(LM.get());
639 Modifiers.push_back(SM.get());
640 Modifiers.push_back(EE.get());
641 Modifiers.push_back(SHM.get());
642 Modifiers.push_back(IE.get());
643 Modifiers.push_back(BM.get());
644 Modifiers.push_back(CM.get());
645 Modifiers.push_back(SLM.get());
646 Modifiers.push_back(PM.get());
648 // Generate the random instructions
649 AllocaModifier AM(BB, &PT, &R); AM.ActN(5); // Throw in a few allocas
650 ConstModifier COM(BB, &PT, &R); COM.ActN(40); // Throw in a few constants
652 for (unsigned i=0; i< SizeCL / Modifiers.size(); ++i)
653 for (std::vector<Modifier*>::iterator it = Modifiers.begin(),
654 e = Modifiers.end(); it != e; ++it) {
658 SM->ActN(5); // Throw in a few stores.
661 static void IntroduceControlFlow(Function *F, Random &R) {
662 std::vector<Instruction*> BoolInst;
663 for (BasicBlock::iterator it = F->begin()->begin(),
664 e = F->begin()->end(); it != e; ++it) {
665 if (it->getType() == IntegerType::getInt1Ty(F->getContext()))
666 BoolInst.push_back(it);
669 std::random_shuffle(BoolInst.begin(), BoolInst.end(), R);
671 for (std::vector<Instruction*>::iterator it = BoolInst.begin(),
672 e = BoolInst.end(); it != e; ++it) {
673 Instruction *Instr = *it;
674 BasicBlock *Curr = Instr->getParent();
675 BasicBlock::iterator Loc= Instr;
676 BasicBlock *Next = Curr->splitBasicBlock(Loc, "CF");
677 Instr->moveBefore(Curr->getTerminator());
678 if (Curr != &F->getEntryBlock()) {
679 BranchInst::Create(Curr, Next, Instr, Curr->getTerminator());
680 Curr->getTerminator()->eraseFromParent();
685 int main(int argc, char **argv) {
686 // Init LLVM, call llvm_shutdown() on exit, parse args, etc.
687 llvm::PrettyStackTraceProgram X(argc, argv);
688 cl::ParseCommandLineOptions(argc, argv, "llvm codegen stress-tester\n");
691 std::unique_ptr<Module> M(new Module("/tmp/autogen.bc", getGlobalContext()));
692 Function *F = GenEmptyFunction(M.get());
694 // Pick an initial seed value
696 // Generate lots of random instructions inside a single basic block.
698 // Break the basic block into many loops.
699 IntroduceControlFlow(F, R);
701 // Figure out what stream we are supposed to write to...
702 std::unique_ptr<tool_output_file> Out;
703 // Default to standard output.
704 if (OutputFilename.empty())
705 OutputFilename = "-";
708 Out.reset(new tool_output_file(OutputFilename, EC, sys::fs::F_None));
710 errs() << EC.message() << '\n';
714 legacy::PassManager Passes;
715 Passes.add(createVerifierPass());
716 Passes.add(createPrintModulePass(Out->os()));
717 Passes.run(*M.get());