1//===-- llvm-stress.cpp - Generate random LL files to stress-test LLVM ----===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This program is a utility that generates random .ll files to stress-test
11// different components in LLVM.
12//
13//===----------------------------------------------------------------------===//
14
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/PassManager.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"
30#include <algorithm>
31#include <set>
32#include <sstream>
33#include <vector>
34using namespace llvm;
35
36static cl::opt<unsigned> SeedCL("seed",
37  cl::desc("Seed used for randomness"), cl::init(0));
38static cl::opt<unsigned> SizeCL("size",
39  cl::desc("The estimated size of the generated function (# of instrs)"),
40  cl::init(100));
41static cl::opt<std::string>
42OutputFilename("o", cl::desc("Override output filename"),
43               cl::value_desc("filename"));
44
45static cl::opt<bool> GenHalfFloat("generate-half-float",
46  cl::desc("Generate half-length floating-point values"), cl::init(false));
47static cl::opt<bool> GenX86FP80("generate-x86-fp80",
48  cl::desc("Generate 80-bit X86 floating-point values"), cl::init(false));
49static cl::opt<bool> GenFP128("generate-fp128",
50  cl::desc("Generate 128-bit floating-point values"), cl::init(false));
51static cl::opt<bool> GenPPCFP128("generate-ppc-fp128",
52  cl::desc("Generate 128-bit PPC floating-point values"), cl::init(false));
53static cl::opt<bool> GenX86MMX("generate-x86-mmx",
54  cl::desc("Generate X86 MMX floating-point values"), cl::init(false));
55
56namespace {
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
60/// number generator.
61class Random {
62public:
63  /// C'tor
64  Random(unsigned _seed):Seed(_seed) {}
65
66  /// Return a random integer, up to a
67  /// maximum of 2**19 - 1.
68  uint32_t Rand() {
69    uint32_t Val = Seed + 0x000b07a1;
70    Seed = (Val * 0x3c7c0ac1);
71    // Only lowest 19 bits are random-ish.
72    return Seed & 0x7ffff;
73  }
74
75  /// Return a random 32 bit integer.
76  uint32_t Rand32() {
77    uint32_t Val = Rand();
78    Val &= 0xffff;
79    return Val | (Rand() << 16);
80  }
81
82  /// Return a random 64 bit integer.
83  uint64_t Rand64() {
84    uint64_t Val = Rand32();
85    return Val | (uint64_t(Rand32()) << 32);
86  }
87
88  /// Rand operator for STL algorithms.
89  ptrdiff_t operator()(ptrdiff_t y) {
90    return  Rand64() % y;
91  }
92
93private:
94  unsigned Seed;
95};
96
97/// Generate an empty function with a default argument list.
98Function *GenEmptyFunction(Module *M) {
99  // Type Definitions
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));
109
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,
115                                    ss.str(), M);
116
117  Func->setCallingConv(CallingConv::C);
118  return Func;
119}
120
121/// A base class, implementing utilities needed for
122/// modifying and adding new random instructions.
123struct Modifier {
124  /// Used to store the randomly generated values.
125  typedef std::vector<Value*> PieceTable;
126
127public:
128  /// C'tor
129  Modifier(BasicBlock *Block, PieceTable *PT, Random *R):
130    BB(Block),PT(PT),Ran(R),Context(BB->getContext()) {}
131
132  /// virtual D'tor to silence warnings.
133  virtual ~Modifier() {}
134
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)
140      Act();
141  }
142
143protected:
144  /// Return a random value from the list of known values.
145  Value *getRandomVal() {
146    assert(PT->size());
147    return PT->at(Ran->Rand() % PT->size());
148  }
149
150  Constant *getRandomConstant(Type *Tp) {
151    if (Tp->isIntegerTy()) {
152      if (Ran->Rand() & 1)
153        return ConstantInt::getAllOnesValue(Tp);
154      return ConstantInt::getNullValue(Tp);
155    } else if (Tp->isFloatingPointTy()) {
156      if (Ran->Rand() & 1)
157        return ConstantFP::getAllOnesValue(Tp);
158      return ConstantFP::getNullValue(Tp);
159    }
160    return UndefValue::get(Tp);
161  }
162
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)
169        return V;
170    }
171
172    // If the requested type was not found, generate a constant value.
173    if (Tp->isIntegerTy()) {
174      if (Ran->Rand() & 1)
175        return ConstantInt::getAllOnesValue(Tp);
176      return ConstantInt::getNullValue(Tp);
177    } else if (Tp->isFloatingPointTy()) {
178      if (Ran->Rand() & 1)
179        return ConstantFP::getAllOnesValue(Tp);
180      return ConstantFP::getNullValue(Tp);
181    } else if (Tp->isVectorTy()) {
182      VectorType *VTp = cast<VectorType>(Tp);
183
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()));
188
189      ArrayRef<Constant*> VectorValue(TempValues);
190      return ConstantVector::get(VectorValue);
191    }
192
193    return UndefValue::get(Tp);
194  }
195
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())
202        return V;
203    }
204    return UndefValue::get(pickPointerType());
205  }
206
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())
213        return V;
214    }
215    return UndefValue::get(pickVectorType());
216  }
217
218  /// Pick a random type.
219  Type *pickType() {
220    return (Ran->Rand() & 1 ? pickVectorType() : pickScalarType());
221  }
222
223  /// Pick a random pointer type.
224  Type *pickPointerType() {
225    Type *Ty = pickType();
226    return PointerType::get(Ty, 0);
227  }
228
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
233    // around 2**3.
234    unsigned width = 1<<((Ran->Rand() % 3) + (Ran->Rand() % 3));
235    Type *Ty;
236
237    // Vectors of x86mmx are illegal; keep trying till we get something else.
238    do {
239      Ty = pickScalarType();
240    } while (Ty->isX86_MMXTy());
241
242    if (len != (unsigned)-1)
243      width = len;
244    return VectorType::get(Ty, width);
245  }
246
247  /// Pick a random scalar type.
248  Type *pickScalarType() {
249    Type *t = nullptr;
250    do {
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;
255      case 3: case 4:
256      case 5: t = Type::getFloatTy(Context); break;
257      case 6: case 7:
258      case 8: t = Type::getDoubleTy(Context); break;
259      case 9: case 10:
260      case 11: t = Type::getInt32Ty(Context); break;
261      case 12: case 13:
262      case 14: t = Type::getInt64Ty(Context); break;
263      case 15: case 16:
264      case 17: if (GenHalfFloat) t = Type::getHalfTy(Context); break;
265      case 18: case 19:
266      case 20: if (GenX86FP80) t = Type::getX86_FP80Ty(Context); break;
267      case 21: case 22:
268      case 23: if (GenFP128) t = Type::getFP128Ty(Context); break;
269      case 24: case 25:
270      case 26: if (GenPPCFP128) t = Type::getPPC_FP128Ty(Context); break;
271      case 27: case 28:
272      case 29: if (GenX86MMX) t = Type::getX86_MMXTy(Context); break;
273      default: llvm_unreachable("Invalid scalar value");
274      }
275    } while (t == nullptr);
276
277    return t;
278  }
279
280  /// Basic block to populate
281  BasicBlock *BB;
282  /// Value table
283  PieceTable *PT;
284  /// Random number generator
285  Random *Ran;
286  /// Context
287  LLVMContext &Context;
288};
289
290struct 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());
296    PT->push_back(V);
297  }
298};
299
300struct 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();
308
309    // Do not store vectors of i1s because they are unsupported
310    // by the codegen.
311    if (ValTy->isVectorTy() && ValTy->getScalarSizeInBits() == 1)
312      return;
313
314    new StoreInst(Val, Ptr, BB->getTerminator());
315  }
316};
317
318struct BinModifier: public Modifier {
319  BinModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
320
321  void Act() override {
322    Value *Val0 = getRandomVal();
323    Value *Val1 = getRandomValue(Val0->getType());
324
325    // Don't handle pointer types.
326    if (Val0->getType()->isPointerTy() ||
327        Val1->getType()->isPointerTy())
328      return;
329
330    // Don't handle i1 types.
331    if (Val0->getType()->getScalarSizeInBits() == 1)
332      return;
333
334
335    bool isFloat = Val0->getType()->getScalarType()->isFloatingPointTy();
336    Instruction* Term = BB->getTerminator();
337    unsigned R = Ran->Rand() % (isFloat ? 7 : 13);
338    Instruction::BinaryOps Op;
339
340    switch (R) {
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; }
355    }
356
357    PT->push_back(BinaryOperator::Create(Op, Val0, Val1, "B", Term));
358  }
359};
360
361/// Generate constant values.
362struct ConstModifier: public Modifier {
363  ConstModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
364  void Act() override {
365    Type *Ty = pickType();
366
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));
373      }
374    }
375
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();
382
383      APInt RandomInt(Ty->getPrimitiveSizeInBits(), makeArrayRef(RandomBits));
384      APFloat RandomFloat(Ty->getFltSemantics(), RandomInt);
385
386      if (Ran->Rand() & 1)
387        return PT->push_back(ConstantFP::getNullValue(Ty));
388      return PT->push_back(ConstantFP::get(Ty->getContext(), RandomFloat));
389    }
390
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()));
402      }
403    }
404
405  }
406};
407
408struct AllocaModifier: public Modifier {
409  AllocaModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R){}
410
411  void Act() override {
412    Type *Tp = pickType();
413    PT->push_back(new AllocaInst(Tp, "A", BB->getFirstNonPHI()));
414  }
415};
416
417struct ExtractElementModifier: public Modifier {
418  ExtractElementModifier(BasicBlock *BB, PieceTable *PT, Random *R):
419    Modifier(BB, PT, R) {}
420
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);
428  }
429};
430
431struct ShuffModifier: public Modifier {
432  ShuffModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
433  void Act() override {
434
435    Value *Val0 = getRandomVectorValue();
436    Value *Val1 = getRandomValue(Val0->getType());
437
438    unsigned Width = cast<VectorType>(Val0->getType())->getNumElements();
439    std::vector<Constant*> Idxs;
440
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);
447      Idxs.push_back(CI);
448    }
449
450    Constant *Mask = ConstantVector::get(Idxs);
451
452    Value *V = new ShuffleVectorInst(Val0, Val1, Mask, "Shuff",
453                                     BB->getTerminator());
454    PT->push_back(V);
455  }
456};
457
458struct InsertElementModifier: public Modifier {
459  InsertElementModifier(BasicBlock *BB, PieceTable *PT, Random *R):
460    Modifier(BB, PT, R) {}
461
462  void Act() override {
463    Value *Val0 = getRandomVectorValue();
464    Value *Val1 = getRandomValue(Val0->getType()->getScalarType());
465
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);
471  }
472
473};
474
475struct CastModifier: public Modifier {
476  CastModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
477  void Act() override {
478
479    Value *V = getRandomVal();
480    Type *VTy = V->getType();
481    Type *DestTy = pickScalarType();
482
483    // Handle vector casts vectors.
484    if (VTy->isVectorTy()) {
485      VectorType *VecTy = cast<VectorType>(VTy);
486      DestTy = pickVectorType(VecTy->getNumElements());
487    }
488
489    // no need to cast.
490    if (VTy == DestTy) return;
491
492    // Pointers:
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()));
498    }
499
500    unsigned VSize = VTy->getScalarType()->getPrimitiveSizeInBits();
501    unsigned DestSize = DestTy->getScalarType()->getPrimitiveSizeInBits();
502
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()));
507    }
508
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()));
515      } else {
516        assert(VSize < DestSize && "Different int types with the same size?");
517        if (Ran->Rand() & 1)
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()));
521      }
522    }
523
524    // Fp to int.
525    if (VTy->getScalarType()->isFloatingPointTy() &&
526        DestTy->getScalarType()->isIntegerTy()) {
527      if (Ran->Rand() & 1)
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()));
531    }
532
533    // Int to fp.
534    if (VTy->getScalarType()->isIntegerTy() &&
535        DestTy->getScalarType()->isFloatingPointTy()) {
536      if (Ran->Rand() & 1)
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()));
540
541    }
542
543    // Both floats.
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()));
552      }
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.
555    }
556  }
557
558};
559
560struct SelectModifier: public Modifier {
561  SelectModifier(BasicBlock *BB, PieceTable *PT, Random *R):
562    Modifier(BB, PT, R) {}
563
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());
568
569      Type *CondTy = Type::getInt1Ty(Context);
570
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);
576      }
577
578      Value *Cond = getRandomValue(CondTy);
579      Value *V = SelectInst::Create(Cond, Val0, Val1, "Sl", BB->getTerminator());
580      return PT->push_back(V);
581  }
582};
583
584
585struct CmpModifier: public Modifier {
586  CmpModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
587  void Act() override {
588
589    Value *Val0 = getRandomVal();
590    Value *Val1 = getRandomValue(Val0->getType());
591
592    if (Val0->getType()->isPointerTy()) return;
593    bool fp = Val0->getType()->getScalarType()->isFloatingPointTy();
594
595    int op;
596    if (fp) {
597      op = Ran->Rand() %
598      (CmpInst::LAST_FCMP_PREDICATE - CmpInst::FIRST_FCMP_PREDICATE) +
599       CmpInst::FIRST_FCMP_PREDICATE;
600    } else {
601      op = Ran->Rand() %
602      (CmpInst::LAST_ICMP_PREDICATE - CmpInst::FIRST_ICMP_PREDICATE) +
603       CmpInst::FIRST_ICMP_PREDICATE;
604    }
605
606    Value *V = CmpInst::Create(fp ? Instruction::FCmp : Instruction::ICmp,
607                               op, Val0, Val1, "Cmp", BB->getTerminator());
608    return PT->push_back(V);
609  }
610};
611
612} // end anonymous namespace
613
614static 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);
618
619  // Create the value table.
620  Modifier::PieceTable PT;
621
622  // Consider arguments as legal values.
623  for (Function::arg_iterator it = F->arg_begin(), e = F->arg_end();
624       it != e; ++it)
625    PT.push_back(it);
626
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());
647
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
651
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) {
655      (*it)->Act();
656    }
657
658  SM->ActN(5); // Throw in a few stores.
659}
660
661static 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);
667  }
668
669  std::random_shuffle(BoolInst.begin(), BoolInst.end(), R);
670
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();
681    }
682  }
683}
684
685int 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");
689  llvm_shutdown_obj Y;
690
691  std::unique_ptr<Module> M(new Module("/tmp/autogen.bc", getGlobalContext()));
692  Function *F = GenEmptyFunction(M.get());
693
694  // Pick an initial seed value
695  Random R(SeedCL);
696  // Generate lots of random instructions inside a single basic block.
697  FillFunction(F, R);
698  // Break the basic block into many loops.
699  IntroduceControlFlow(F, R);
700
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 = "-";
706
707  std::string ErrorInfo;
708  Out.reset(new tool_output_file(OutputFilename.c_str(), ErrorInfo,
709                                 sys::fs::F_None));
710  if (!ErrorInfo.empty()) {
711    errs() << ErrorInfo << '\n';
712    return 1;
713  }
714
715  PassManager Passes;
716  Passes.add(createVerifierPass());
717  Passes.add(createDebugInfoVerifierPass());
718  Passes.add(createPrintModulePass(Out->os()));
719  Passes.run(*M.get());
720  Out->keep();
721
722  return 0;
723}
724