src/llvm/tools/llvm-stress/llvm-stress.cpp

   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 #include "llvm/LLVMContext.h"
  15 #include "llvm/Module.h"
  16 #include "llvm/PassManager.h"
  17 #include "llvm/Constants.h"
  18 #include "llvm/Instruction.h"
  19 #include "llvm/CallGraphSCCPass.h"
  20 #include "llvm/Assembly/PrintModulePass.h"
  21 #include "llvm/Analysis/Verifier.h"
  22 #include "llvm/Support/PassNameParser.h"
  23 #include "llvm/Support/Debug.h"
  24 #include "llvm/Support/ManagedStatic.h"
  25 #include "llvm/Support/PluginLoader.h"
  26 #include "llvm/Support/PrettyStackTrace.h"
  27 #include "llvm/Support/ToolOutputFile.h"
  28 #include <memory>
  29 #include <sstream>
  30 #include <set>
  31 #include <vector>
  32 #include <algorithm>
  33 using namespace llvm;
  34
  35 static cl::opt<unsigned> SeedCL("seed",
  36   cl::desc("Seed used for randomness"), cl::init(0));
  37 static cl::opt<unsigned> SizeCL("size",
  38   cl::desc("The estimated size of the generated function (# of instrs)"),
  39   cl::init(100));
  40 static cl::opt<std::string>
  41 OutputFilename("o", cl::desc("Override output filename"),
  42                cl::value_desc("filename"));
  43
  44 static cl::opt<bool> GenHalfFloat("generate-half-float",
  45   cl::desc("Generate half-length floating-point values"), cl::init(false));
  46 static cl::opt<bool> GenX86FP80("generate-x86-fp80",
  47   cl::desc("Generate 80-bit X86 floating-point values"), cl::init(false));
  48 static cl::opt<bool> GenFP128("generate-fp128",
  49   cl::desc("Generate 128-bit floating-point values"), cl::init(false));
  50 static cl::opt<bool> GenPPCFP128("generate-ppc-fp128",
  51   cl::desc("Generate 128-bit PPC floating-point values"), cl::init(false));
  52 static cl::opt<bool> GenX86MMX("generate-x86-mmx",
  53   cl::desc("Generate X86 MMX floating-point values"), cl::init(false));
  54
  55 /// A utility class to provide a pseudo-random number generator which is
  56 /// the same across all platforms. This is somewhat close to the libc
  57 /// implementation. Note: This is not a cryptographically secure pseudorandom
  58 /// number generator.
  59 class Random {
  60 public:
  61   /// C'tor
  62   Random(unsigned _seed):Seed(_seed) {}
  63
  64   /// Return a random integer, up to a
  65   /// maximum of 2**19 - 1.
  66   uint32_t Rand() {
  67     uint32_t Val = Seed + 0x000b07a1;
  68     Seed = (Val * 0x3c7c0ac1);
  69     // Only lowest 19 bits are random-ish.
  70     return Seed & 0x7ffff;
  71   }
  72
  73   /// Return a random 32 bit integer.
  74   uint32_t Rand32() {
  75     uint32_t Val = Rand();
  76     Val &= 0xffff;
  77     return Val | (Rand() << 16);
  78   }
  79
  80   /// Return a random 64 bit integer.
  81   uint64_t Rand64() {
  82     uint64_t Val = Rand32();
  83     return Val | (uint64_t(Rand32()) << 32);
  84   }
  85
  86   /// Rand operator for STL algorithms.
  87   ptrdiff_t operator()(ptrdiff_t y) {
  88     return  Rand64() % y;
  89   }
  90
  91 private:
  92   unsigned Seed;
  93 };
  94
  95 /// Generate an empty function with a default argument list.
  96 Function *GenEmptyFunction(Module *M) {
  97   // Type Definitions
  98   std::vector<Type*> ArgsTy;
  99   // Define a few arguments
 100   LLVMContext &Context = M->getContext();
 101   ArgsTy.push_back(PointerType::get(IntegerType::getInt8Ty(Context), 0));
 102   ArgsTy.push_back(PointerType::get(IntegerType::getInt32Ty(Context), 0));
 103   ArgsTy.push_back(PointerType::get(IntegerType::getInt64Ty(Context), 0));
 104   ArgsTy.push_back(IntegerType::getInt32Ty(Context));
 105   ArgsTy.push_back(IntegerType::getInt64Ty(Context));
 106   ArgsTy.push_back(IntegerType::getInt8Ty(Context));
 107
 108   FunctionType *FuncTy = FunctionType::get(Type::getVoidTy(Context), ArgsTy, 0);
 109   // Pick a unique name to describe the input parameters
 110   std::stringstream ss;
 111   ss<<"autogen_SD"<<SeedCL;
 112   Function *Func = Function::Create(FuncTy, GlobalValue::ExternalLinkage,
 113                                     ss.str(), M);
 114
 115   Func->setCallingConv(CallingConv::C);
 116   return Func;
 117 }
 118
 119 /// A base class, implementing utilities needed for
 120 /// modifying and adding new random instructions.
 121 struct Modifier {
 122   /// Used to store the randomly generated values.
 123   typedef std::vector<Value*> PieceTable;
 124
 125 public:
 126   /// C'tor
 127   Modifier(BasicBlock *Block, PieceTable *PT, Random *R):
 128     BB(Block),PT(PT),Ran(R),Context(BB->getContext()) {}
 129
 130   /// virtual D'tor to silence warnings.
 131   virtual ~Modifier() {}
 132
 133   /// Add a new instruction.
 134   virtual void Act() = 0;
 135   /// Add N new instructions,
 136   virtual void ActN(unsigned n) {
 137     for (unsigned i=0; i<n; ++i)
 138       Act();
 139   }
 140
 141 protected:
 142   /// Return a random value from the list of known values.
 143   Value *getRandomVal() {
 144     assert(PT->size());
 145     return PT->at(Ran->Rand() % PT->size());
 146   }
 147
 148   Constant *getRandomConstant(Type *Tp) {
 149     if (Tp->isIntegerTy()) {
 150       if (Ran->Rand() & 1)
 151         return ConstantInt::getAllOnesValue(Tp);
 152       return ConstantInt::getNullValue(Tp);
 153     } else if (Tp->isFloatingPointTy()) {
 154       if (Ran->Rand() & 1)
 155         return ConstantFP::getAllOnesValue(Tp);
 156       return ConstantFP::getNullValue(Tp);
 157     }
 158     return UndefValue::get(Tp);
 159   }
 160
 161   /// Return a random value with a known type.
 162   Value *getRandomValue(Type *Tp) {
 163     unsigned index = Ran->Rand();
 164     for (unsigned i=0; i<PT->size(); ++i) {
 165       Value *V = PT->at((index + i) % PT->size());
 166       if (V->getType() == Tp)
 167         return V;
 168     }
 169
 170     // If the requested type was not found, generate a constant value.
 171     if (Tp->isIntegerTy()) {
 172       if (Ran->Rand() & 1)
 173         return ConstantInt::getAllOnesValue(Tp);
 174       return ConstantInt::getNullValue(Tp);
 175     } else if (Tp->isFloatingPointTy()) {
 176       if (Ran->Rand() & 1)
 177         return ConstantFP::getAllOnesValue(Tp);
 178       return ConstantFP::getNullValue(Tp);
 179     } else if (Tp->isVectorTy()) {
 180       VectorType *VTp = cast<VectorType>(Tp);
 181
 182       std::vector<Constant*> TempValues;
 183       TempValues.reserve(VTp->getNumElements());
 184       for (unsigned i = 0; i < VTp->getNumElements(); ++i)
 185         TempValues.push_back(getRandomConstant(VTp->getScalarType()));
 186
 187       ArrayRef<Constant*> VectorValue(TempValues);
 188       return ConstantVector::get(VectorValue);
 189     }
 190
 191     return UndefValue::get(Tp);
 192   }
 193
 194   /// Return a random value of any pointer type.
 195   Value *getRandomPointerValue() {
 196     unsigned index = Ran->Rand();
 197     for (unsigned i=0; i<PT->size(); ++i) {
 198       Value *V = PT->at((index + i) % PT->size());
 199       if (V->getType()->isPointerTy())
 200         return V;
 201     }
 202     return UndefValue::get(pickPointerType());
 203   }
 204
 205   /// Return a random value of any vector type.
 206   Value *getRandomVectorValue() {
 207     unsigned index = Ran->Rand();
 208     for (unsigned i=0; i<PT->size(); ++i) {
 209       Value *V = PT->at((index + i) % PT->size());
 210       if (V->getType()->isVectorTy())
 211         return V;
 212     }
 213     return UndefValue::get(pickVectorType());
 214   }
 215
 216   /// Pick a random type.
 217   Type *pickType() {
 218     return (Ran->Rand() & 1 ? pickVectorType() : pickScalarType());
 219   }
 220
 221   /// Pick a random pointer type.
 222   Type *pickPointerType() {
 223     Type *Ty = pickType();
 224     return PointerType::get(Ty, 0);
 225   }
 226
 227   /// Pick a random vector type.
 228   Type *pickVectorType(unsigned len = (unsigned)-1) {
 229     // Pick a random vector width in the range 2**0 to 2**4.
 230     // by adding two randoms we are generating a normal-like distribution
 231     // around 2**3.
 232     unsigned width = 1<<((Ran->Rand() % 3) + (Ran->Rand() % 3));
 233     Type *Ty;
 234
 235     // Vectors of x86mmx are illegal; keep trying till we get something else.
 236     do {
 237       Ty = pickScalarType();
 238     } while (Ty->isX86_MMXTy());
 239
 240     if (len != (unsigned)-1)
 241       width = len;
 242     return VectorType::get(Ty, width);
 243   }
 244
 245   /// Pick a random scalar type.
 246   Type *pickScalarType() {
 247     Type *t = 0;
 248     do {
 249       switch (Ran->Rand() % 30) {
 250       case 0: t = Type::getInt1Ty(Context); break;
 251       case 1: t = Type::getInt8Ty(Context); break;
 252       case 2: t = Type::getInt16Ty(Context); break;
 253       case 3: case 4:
 254       case 5: t = Type::getFloatTy(Context); break;
 255       case 6: case 7:
 256       case 8: t = Type::getDoubleTy(Context); break;
 257       case 9: case 10:
 258       case 11: t = Type::getInt32Ty(Context); break;
 259       case 12: case 13:
 260       case 14: t = Type::getInt64Ty(Context); break;
 261       case 15: case 16:
 262       case 17: if (GenHalfFloat) t = Type::getHalfTy(Context); break;
 263       case 18: case 19:
 264       case 20: if (GenX86FP80) t = Type::getX86_FP80Ty(Context); break;
 265       case 21: case 22:
 266       case 23: if (GenFP128) t = Type::getFP128Ty(Context); break;
 267       case 24: case 25:
 268       case 26: if (GenPPCFP128) t = Type::getPPC_FP128Ty(Context); break;
 269       case 27: case 28:
 270       case 29: if (GenX86MMX) t = Type::getX86_MMXTy(Context); break;
 271       default: llvm_unreachable("Invalid scalar value");
 272       }
 273     } while (t == 0);
 274
 275     return t;
 276   }
 277
 278   /// Basic block to populate
 279   BasicBlock *BB;
 280   /// Value table
 281   PieceTable *PT;
 282   /// Random number generator
 283   Random *Ran;
 284   /// Context
 285   LLVMContext &Context;
 286 };
 287
 288 struct LoadModifier: public Modifier {
 289   LoadModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
 290   virtual void Act() {
 291     // Try to use predefined pointers. If non exist, use undef pointer value;
 292     Value *Ptr = getRandomPointerValue();
 293     Value *V = new LoadInst(Ptr, "L", BB->getTerminator());
 294     PT->push_back(V);
 295   }
 296 };
 297
 298 struct StoreModifier: public Modifier {
 299   StoreModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
 300   virtual void Act() {
 301     // Try to use predefined pointers. If non exist, use undef pointer value;
 302     Value *Ptr = getRandomPointerValue();
 303     Type  *Tp = Ptr->getType();
 304     Value *Val = getRandomValue(Tp->getContainedType(0));
 305     Type  *ValTy = Val->getType();
 306
 307     // Do not store vectors of i1s because they are unsupported
 308     // by the codegen.
 309     if (ValTy->isVectorTy() && ValTy->getScalarSizeInBits() == 1)
 310       return;
 311
 312     new StoreInst(Val, Ptr, BB->getTerminator());
 313   }
 314 };
 315
 316 struct BinModifier: public Modifier {
 317   BinModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
 318
 319   virtual void Act() {
 320     Value *Val0 = getRandomVal();
 321     Value *Val1 = getRandomValue(Val0->getType());
 322
 323     // Don't handle pointer types.
 324     if (Val0->getType()->isPointerTy() ||
 325         Val1->getType()->isPointerTy())
 326       return;
 327
 328     // Don't handle i1 types.
 329     if (Val0->getType()->getScalarSizeInBits() == 1)
 330       return;
 331
 332
 333     bool isFloat = Val0->getType()->getScalarType()->isFloatingPointTy();
 334     Instruction* Term = BB->getTerminator();
 335     unsigned R = Ran->Rand() % (isFloat ? 7 : 13);
 336     Instruction::BinaryOps Op;
 337
 338     switch (R) {
 339     default: llvm_unreachable("Invalid BinOp");
 340     case 0:{Op = (isFloat?Instruction::FAdd : Instruction::Add); break; }
 341     case 1:{Op = (isFloat?Instruction::FSub : Instruction::Sub); break; }
 342     case 2:{Op = (isFloat?Instruction::FMul : Instruction::Mul); break; }
 343     case 3:{Op = (isFloat?Instruction::FDiv : Instruction::SDiv); break; }
 344     case 4:{Op = (isFloat?Instruction::FDiv : Instruction::UDiv); break; }
 345     case 5:{Op = (isFloat?Instruction::FRem : Instruction::SRem); break; }
 346     case 6:{Op = (isFloat?Instruction::FRem : Instruction::URem); break; }
 347     case 7: {Op = Instruction::Shl;  break; }
 348     case 8: {Op = Instruction::LShr; break; }
 349     case 9: {Op = Instruction::AShr; break; }
 350     case 10:{Op = Instruction::And;  break; }
 351     case 11:{Op = Instruction::Or;   break; }
 352     case 12:{Op = Instruction::Xor;  break; }
 353     }
 354
 355     PT->push_back(BinaryOperator::Create(Op, Val0, Val1, "B", Term));
 356   }
 357 };
 358
 359 /// Generate constant values.
 360 struct ConstModifier: public Modifier {
 361   ConstModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
 362   virtual void Act() {
 363     Type *Ty = pickType();
 364
 365     if (Ty->isVectorTy()) {
 366       switch (Ran->Rand() % 2) {
 367       case 0: if (Ty->getScalarType()->isIntegerTy())
 368                 return PT->push_back(ConstantVector::getAllOnesValue(Ty));
 369       case 1: if (Ty->getScalarType()->isIntegerTy())
 370                 return PT->push_back(ConstantVector::getNullValue(Ty));
 371       }
 372     }
 373
 374     if (Ty->isFloatingPointTy()) {
 375       // Generate 128 random bits, the size of the (currently)
 376       // largest floating-point types.
 377       uint64_t RandomBits[2];
 378       for (unsigned i = 0; i < 2; ++i)
 379         RandomBits[i] = Ran->Rand64();
 380
 381       APInt RandomInt(Ty->getPrimitiveSizeInBits(), makeArrayRef(RandomBits));
 382
 383       bool isIEEE = !Ty->isX86_FP80Ty() && !Ty->isPPC_FP128Ty();
 384       APFloat RandomFloat(RandomInt, isIEEE);
 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
 408 struct AllocaModifier: public Modifier {
 409   AllocaModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R){}
 410
 411   virtual void Act() {
 412     Type *Tp = pickType();
 413     PT->push_back(new AllocaInst(Tp, "A", BB->getFirstNonPHI()));
 414   }
 415 };
 416
 417 struct ExtractElementModifier: public Modifier {
 418   ExtractElementModifier(BasicBlock *BB, PieceTable *PT, Random *R):
 419     Modifier(BB, PT, R) {}
 420
 421   virtual void Act() {
 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
 431 struct ShuffModifier: public Modifier {
 432   ShuffModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
 433   virtual void Act() {
 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
 458 struct InsertElementModifier: public Modifier {
 459   InsertElementModifier(BasicBlock *BB, PieceTable *PT, Random *R):
 460     Modifier(BB, PT, R) {}
 461
 462   virtual void Act() {
 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
 475 struct CastModifier: public Modifier {
 476   CastModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
 477   virtual void Act() {
 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
 560 struct SelectModifier: public Modifier {
 561   SelectModifier(BasicBlock *BB, PieceTable *PT, Random *R):
 562     Modifier(BB, PT, R) {}
 563
 564   virtual void Act() {
 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
 585 struct CmpModifier: public Modifier {
 586   CmpModifier(BasicBlock *BB, PieceTable *PT, Random *R):Modifier(BB, PT, R) {}
 587   virtual void Act() {
 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 void FillFunction(Function *F, Random &R) {
 613   // Create a legal entry block.
 614   BasicBlock *BB = BasicBlock::Create(F->getContext(), "BB", F);
 615   ReturnInst::Create(F->getContext(), BB);
 616
 617   // Create the value table.
 618   Modifier::PieceTable PT;
 619
 620   // Consider arguments as legal values.
 621   for (Function::arg_iterator it = F->arg_begin(), e = F->arg_end();
 622        it != e; ++it)
 623     PT.push_back(it);
 624
 625   // List of modifiers which add new random instructions.
 626   std::vector<Modifier*> Modifiers;
 627   std::auto_ptr<Modifier> LM(new LoadModifier(BB, &PT, &R));
 628   std::auto_ptr<Modifier> SM(new StoreModifier(BB, &PT, &R));
 629   std::auto_ptr<Modifier> EE(new ExtractElementModifier(BB, &PT, &R));
 630   std::auto_ptr<Modifier> SHM(new ShuffModifier(BB, &PT, &R));
 631   std::auto_ptr<Modifier> IE(new InsertElementModifier(BB, &PT, &R));
 632   std::auto_ptr<Modifier> BM(new BinModifier(BB, &PT, &R));
 633   std::auto_ptr<Modifier> CM(new CastModifier(BB, &PT, &R));
 634   std::auto_ptr<Modifier> SLM(new SelectModifier(BB, &PT, &R));
 635   std::auto_ptr<Modifier> PM(new CmpModifier(BB, &PT, &R));
 636   Modifiers.push_back(LM.get());
 637   Modifiers.push_back(SM.get());
 638   Modifiers.push_back(EE.get());
 639   Modifiers.push_back(SHM.get());
 640   Modifiers.push_back(IE.get());
 641   Modifiers.push_back(BM.get());
 642   Modifiers.push_back(CM.get());
 643   Modifiers.push_back(SLM.get());
 644   Modifiers.push_back(PM.get());
 645
 646   // Generate the random instructions
 647   AllocaModifier AM(BB, &PT, &R); AM.ActN(5); // Throw in a few allocas
 648   ConstModifier COM(BB, &PT, &R);  COM.ActN(40); // Throw in a few constants
 649
 650   for (unsigned i=0; i< SizeCL / Modifiers.size(); ++i)
 651     for (std::vector<Modifier*>::iterator it = Modifiers.begin(),
 652          e = Modifiers.end(); it != e; ++it) {
 653       (*it)->Act();
 654     }
 655
 656   SM->ActN(5); // Throw in a few stores.
 657 }
 658
 659 void IntroduceControlFlow(Function *F, Random &R) {
 660   std::vector<Instruction*> BoolInst;
 661   for (BasicBlock::iterator it = F->begin()->begin(),
 662        e = F->begin()->end(); it != e; ++it) {
 663     if (it->getType() == IntegerType::getInt1Ty(F->getContext()))
 664       BoolInst.push_back(it);
 665   }
 666
 667   std::random_shuffle(BoolInst.begin(), BoolInst.end(), R);
 668
 669   for (std::vector<Instruction*>::iterator it = BoolInst.begin(),
 670        e = BoolInst.end(); it != e; ++it) {
 671     Instruction *Instr = *it;
 672     BasicBlock *Curr = Instr->getParent();
 673     BasicBlock::iterator Loc= Instr;
 674     BasicBlock *Next = Curr->splitBasicBlock(Loc, "CF");
 675     Instr->moveBefore(Curr->getTerminator());
 676     if (Curr != &F->getEntryBlock()) {
 677       BranchInst::Create(Curr, Next, Instr, Curr->getTerminator());
 678       Curr->getTerminator()->eraseFromParent();
 679     }
 680   }
 681 }
 682
 683 int main(int argc, char **argv) {
 684   // Init LLVM, call llvm_shutdown() on exit, parse args, etc.
 685   llvm::PrettyStackTraceProgram X(argc, argv);
 686   cl::ParseCommandLineOptions(argc, argv, "llvm codegen stress-tester\n");
 687   llvm_shutdown_obj Y;
 688
 689   std::auto_ptr<Module> M(new Module("/tmp/autogen.bc", getGlobalContext()));
 690   Function *F = GenEmptyFunction(M.get());
 691
 692   // Pick an initial seed value
 693   Random R(SeedCL);
 694   // Generate lots of random instructions inside a single basic block.
 695   FillFunction(F, R);
 696   // Break the basic block into many loops.
 697   IntroduceControlFlow(F, R);
 698
 699   // Figure out what stream we are supposed to write to...
 700   OwningPtr<tool_output_file> Out;
 701   // Default to standard output.
 702   if (OutputFilename.empty())
 703     OutputFilename = "-";
 704
 705   std::string ErrorInfo;
 706   Out.reset(new tool_output_file(OutputFilename.c_str(), ErrorInfo,
 707                                  raw_fd_ostream::F_Binary));
 708   if (!ErrorInfo.empty()) {
 709     errs() << ErrorInfo << '\n';
 710     return 1;
 711   }
 712
 713   PassManager Passes;
 714   Passes.add(createVerifierPass());
 715   Passes.add(createPrintModulePass(&Out->os()));
 716   Passes.run(*M.get());
 717   Out->keep();
 718
 719   return 0;
 720 }