IntrinsicLowering.cpp revision eaff5246707cc620736e895c239ff78298b3d95e
1//===-- IntrinsicLowering.cpp - Intrinsic Lowering default implementation -===// 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 file implements the IntrinsicLowering class. 11// 12//===----------------------------------------------------------------------===// 13 14#include "llvm/Constants.h" 15#include "llvm/DerivedTypes.h" 16#include "llvm/Module.h" 17#include "llvm/Type.h" 18#include "llvm/CodeGen/IntrinsicLowering.h" 19#include "llvm/Support/IRBuilder.h" 20#include "llvm/Support/ErrorHandling.h" 21#include "llvm/Target/TargetData.h" 22#include "llvm/ADT/SmallVector.h" 23using namespace llvm; 24 25template <class ArgIt> 26static void EnsureFunctionExists(Module &M, const char *Name, 27 ArgIt ArgBegin, ArgIt ArgEnd, 28 const Type *RetTy) { 29 // Insert a correctly-typed definition now. 30 std::vector<const Type *> ParamTys; 31 for (ArgIt I = ArgBegin; I != ArgEnd; ++I) 32 ParamTys.push_back(I->getType()); 33 M.getOrInsertFunction(Name, FunctionType::get(RetTy, ParamTys, false)); 34} 35 36static void EnsureFPIntrinsicsExist(Module &M, Function *Fn, 37 const char *FName, 38 const char *DName, const char *LDName) { 39 // Insert definitions for all the floating point types. 40 switch((int)Fn->arg_begin()->getType()->getTypeID()) { 41 case Type::FloatTyID: 42 EnsureFunctionExists(M, FName, Fn->arg_begin(), Fn->arg_end(), 43 Type::FloatTy); 44 break; 45 case Type::DoubleTyID: 46 EnsureFunctionExists(M, DName, Fn->arg_begin(), Fn->arg_end(), 47 Type::DoubleTy); 48 break; 49 case Type::X86_FP80TyID: 50 case Type::FP128TyID: 51 case Type::PPC_FP128TyID: 52 EnsureFunctionExists(M, LDName, Fn->arg_begin(), Fn->arg_end(), 53 Fn->arg_begin()->getType()); 54 break; 55 } 56} 57 58/// ReplaceCallWith - This function is used when we want to lower an intrinsic 59/// call to a call of an external function. This handles hard cases such as 60/// when there was already a prototype for the external function, and if that 61/// prototype doesn't match the arguments we expect to pass in. 62template <class ArgIt> 63static CallInst *ReplaceCallWith(const char *NewFn, CallInst *CI, 64 ArgIt ArgBegin, ArgIt ArgEnd, 65 const Type *RetTy) { 66 // If we haven't already looked up this function, check to see if the 67 // program already contains a function with this name. 68 Module *M = CI->getParent()->getParent()->getParent(); 69 // Get or insert the definition now. 70 std::vector<const Type *> ParamTys; 71 for (ArgIt I = ArgBegin; I != ArgEnd; ++I) 72 ParamTys.push_back((*I)->getType()); 73 Constant* FCache = M->getOrInsertFunction(NewFn, 74 FunctionType::get(RetTy, ParamTys, false)); 75 76 IRBuilder<> Builder(CI->getParent(), CI); 77 SmallVector<Value *, 8> Args(ArgBegin, ArgEnd); 78 CallInst *NewCI = Builder.CreateCall(FCache, Args.begin(), Args.end()); 79 NewCI->setName(CI->getName()); 80 if (!CI->use_empty()) 81 CI->replaceAllUsesWith(NewCI); 82 return NewCI; 83} 84 85void IntrinsicLowering::AddPrototypes(Module &M) { 86 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) 87 if (I->isDeclaration() && !I->use_empty()) 88 switch (I->getIntrinsicID()) { 89 default: break; 90 case Intrinsic::setjmp: 91 EnsureFunctionExists(M, "setjmp", I->arg_begin(), I->arg_end(), 92 Type::Int32Ty); 93 break; 94 case Intrinsic::longjmp: 95 EnsureFunctionExists(M, "longjmp", I->arg_begin(), I->arg_end(), 96 Type::VoidTy); 97 break; 98 case Intrinsic::siglongjmp: 99 EnsureFunctionExists(M, "abort", I->arg_end(), I->arg_end(), 100 Type::VoidTy); 101 break; 102 case Intrinsic::memcpy: 103 M.getOrInsertFunction("memcpy", PointerType::getUnqual(Type::Int8Ty), 104 PointerType::getUnqual(Type::Int8Ty), 105 PointerType::getUnqual(Type::Int8Ty), 106 TD.getIntPtrType(), (Type *)0); 107 break; 108 case Intrinsic::memmove: 109 M.getOrInsertFunction("memmove", PointerType::getUnqual(Type::Int8Ty), 110 PointerType::getUnqual(Type::Int8Ty), 111 PointerType::getUnqual(Type::Int8Ty), 112 TD.getIntPtrType(), (Type *)0); 113 break; 114 case Intrinsic::memset: 115 M.getOrInsertFunction("memset", PointerType::getUnqual(Type::Int8Ty), 116 PointerType::getUnqual(Type::Int8Ty), 117 Type::Int32Ty, 118 TD.getIntPtrType(), (Type *)0); 119 break; 120 case Intrinsic::sqrt: 121 EnsureFPIntrinsicsExist(M, I, "sqrtf", "sqrt", "sqrtl"); 122 break; 123 case Intrinsic::sin: 124 EnsureFPIntrinsicsExist(M, I, "sinf", "sin", "sinl"); 125 break; 126 case Intrinsic::cos: 127 EnsureFPIntrinsicsExist(M, I, "cosf", "cos", "cosl"); 128 break; 129 case Intrinsic::pow: 130 EnsureFPIntrinsicsExist(M, I, "powf", "pow", "powl"); 131 break; 132 case Intrinsic::log: 133 EnsureFPIntrinsicsExist(M, I, "logf", "log", "logl"); 134 break; 135 case Intrinsic::log2: 136 EnsureFPIntrinsicsExist(M, I, "log2f", "log2", "log2l"); 137 break; 138 case Intrinsic::log10: 139 EnsureFPIntrinsicsExist(M, I, "log10f", "log10", "log10l"); 140 break; 141 case Intrinsic::exp: 142 EnsureFPIntrinsicsExist(M, I, "expf", "exp", "expl"); 143 break; 144 case Intrinsic::exp2: 145 EnsureFPIntrinsicsExist(M, I, "exp2f", "exp2", "exp2l"); 146 break; 147 } 148} 149 150/// LowerBSWAP - Emit the code to lower bswap of V before the specified 151/// instruction IP. 152static Value *LowerBSWAP(Value *V, Instruction *IP) { 153 assert(V->getType()->isInteger() && "Can't bswap a non-integer type!"); 154 155 unsigned BitSize = V->getType()->getPrimitiveSizeInBits(); 156 157 IRBuilder<> Builder(IP->getParent(), IP); 158 159 switch(BitSize) { 160 default: LLVM_UNREACHABLE("Unhandled type size of value to byteswap!"); 161 case 16: { 162 Value *Tmp1 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 8), 163 "bswap.2"); 164 Value *Tmp2 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 8), 165 "bswap.1"); 166 V = Builder.CreateOr(Tmp1, Tmp2, "bswap.i16"); 167 break; 168 } 169 case 32: { 170 Value *Tmp4 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 24), 171 "bswap.4"); 172 Value *Tmp3 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 8), 173 "bswap.3"); 174 Value *Tmp2 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 8), 175 "bswap.2"); 176 Value *Tmp1 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 24), 177 "bswap.1"); 178 Tmp3 = Builder.CreateAnd(Tmp3, ConstantInt::get(Type::Int32Ty, 0xFF0000), 179 "bswap.and3"); 180 Tmp2 = Builder.CreateAnd(Tmp2, ConstantInt::get(Type::Int32Ty, 0xFF00), 181 "bswap.and2"); 182 Tmp4 = Builder.CreateOr(Tmp4, Tmp3, "bswap.or1"); 183 Tmp2 = Builder.CreateOr(Tmp2, Tmp1, "bswap.or2"); 184 V = Builder.CreateOr(Tmp4, Tmp2, "bswap.i32"); 185 break; 186 } 187 case 64: { 188 Value *Tmp8 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 56), 189 "bswap.8"); 190 Value *Tmp7 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 40), 191 "bswap.7"); 192 Value *Tmp6 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 24), 193 "bswap.6"); 194 Value *Tmp5 = Builder.CreateShl(V, ConstantInt::get(V->getType(), 8), 195 "bswap.5"); 196 Value* Tmp4 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 8), 197 "bswap.4"); 198 Value* Tmp3 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 24), 199 "bswap.3"); 200 Value* Tmp2 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 40), 201 "bswap.2"); 202 Value* Tmp1 = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 56), 203 "bswap.1"); 204 Tmp7 = Builder.CreateAnd(Tmp7, 205 ConstantInt::get(Type::Int64Ty, 206 0xFF000000000000ULL), 207 "bswap.and7"); 208 Tmp6 = Builder.CreateAnd(Tmp6, 209 ConstantInt::get(Type::Int64Ty, 210 0xFF0000000000ULL), 211 "bswap.and6"); 212 Tmp5 = Builder.CreateAnd(Tmp5, 213 ConstantInt::get(Type::Int64Ty, 0xFF00000000ULL), 214 "bswap.and5"); 215 Tmp4 = Builder.CreateAnd(Tmp4, 216 ConstantInt::get(Type::Int64Ty, 0xFF000000ULL), 217 "bswap.and4"); 218 Tmp3 = Builder.CreateAnd(Tmp3, 219 ConstantInt::get(Type::Int64Ty, 0xFF0000ULL), 220 "bswap.and3"); 221 Tmp2 = Builder.CreateAnd(Tmp2, 222 ConstantInt::get(Type::Int64Ty, 0xFF00ULL), 223 "bswap.and2"); 224 Tmp8 = Builder.CreateOr(Tmp8, Tmp7, "bswap.or1"); 225 Tmp6 = Builder.CreateOr(Tmp6, Tmp5, "bswap.or2"); 226 Tmp4 = Builder.CreateOr(Tmp4, Tmp3, "bswap.or3"); 227 Tmp2 = Builder.CreateOr(Tmp2, Tmp1, "bswap.or4"); 228 Tmp8 = Builder.CreateOr(Tmp8, Tmp6, "bswap.or5"); 229 Tmp4 = Builder.CreateOr(Tmp4, Tmp2, "bswap.or6"); 230 V = Builder.CreateOr(Tmp8, Tmp4, "bswap.i64"); 231 break; 232 } 233 } 234 return V; 235} 236 237/// LowerCTPOP - Emit the code to lower ctpop of V before the specified 238/// instruction IP. 239static Value *LowerCTPOP(Value *V, Instruction *IP) { 240 assert(V->getType()->isInteger() && "Can't ctpop a non-integer type!"); 241 242 static const uint64_t MaskValues[6] = { 243 0x5555555555555555ULL, 0x3333333333333333ULL, 244 0x0F0F0F0F0F0F0F0FULL, 0x00FF00FF00FF00FFULL, 245 0x0000FFFF0000FFFFULL, 0x00000000FFFFFFFFULL 246 }; 247 248 IRBuilder<> Builder(IP->getParent(), IP); 249 250 unsigned BitSize = V->getType()->getPrimitiveSizeInBits(); 251 unsigned WordSize = (BitSize + 63) / 64; 252 Value *Count = ConstantInt::get(V->getType(), 0); 253 254 for (unsigned n = 0; n < WordSize; ++n) { 255 Value *PartValue = V; 256 for (unsigned i = 1, ct = 0; i < (BitSize>64 ? 64 : BitSize); 257 i <<= 1, ++ct) { 258 Value *MaskCst = ConstantInt::get(V->getType(), MaskValues[ct]); 259 Value *LHS = Builder.CreateAnd(PartValue, MaskCst, "cppop.and1"); 260 Value *VShift = Builder.CreateLShr(PartValue, 261 ConstantInt::get(V->getType(), i), 262 "ctpop.sh"); 263 Value *RHS = Builder.CreateAnd(VShift, MaskCst, "cppop.and2"); 264 PartValue = Builder.CreateAdd(LHS, RHS, "ctpop.step"); 265 } 266 Count = Builder.CreateAdd(PartValue, Count, "ctpop.part"); 267 if (BitSize > 64) { 268 V = Builder.CreateLShr(V, ConstantInt::get(V->getType(), 64), 269 "ctpop.part.sh"); 270 BitSize -= 64; 271 } 272 } 273 274 return Count; 275} 276 277/// LowerCTLZ - Emit the code to lower ctlz of V before the specified 278/// instruction IP. 279static Value *LowerCTLZ(Value *V, Instruction *IP) { 280 281 IRBuilder<> Builder(IP->getParent(), IP); 282 283 unsigned BitSize = V->getType()->getPrimitiveSizeInBits(); 284 for (unsigned i = 1; i < BitSize; i <<= 1) { 285 Value *ShVal = ConstantInt::get(V->getType(), i); 286 ShVal = Builder.CreateLShr(V, ShVal, "ctlz.sh"); 287 V = Builder.CreateOr(V, ShVal, "ctlz.step"); 288 } 289 290 V = Builder.CreateNot(V); 291 return LowerCTPOP(V, IP); 292} 293 294static void ReplaceFPIntrinsicWithCall(CallInst *CI, const char *Fname, 295 const char *Dname, 296 const char *LDname) { 297 switch (CI->getOperand(1)->getType()->getTypeID()) { 298 default: LLVM_UNREACHABLE( "Invalid type in intrinsic"); 299 case Type::FloatTyID: 300 ReplaceCallWith(Fname, CI, CI->op_begin() + 1, CI->op_end(), 301 Type::FloatTy); 302 break; 303 case Type::DoubleTyID: 304 ReplaceCallWith(Dname, CI, CI->op_begin() + 1, CI->op_end(), 305 Type::DoubleTy); 306 break; 307 case Type::X86_FP80TyID: 308 case Type::FP128TyID: 309 case Type::PPC_FP128TyID: 310 ReplaceCallWith(LDname, CI, CI->op_begin() + 1, CI->op_end(), 311 CI->getOperand(1)->getType()); 312 break; 313 } 314} 315 316void IntrinsicLowering::LowerIntrinsicCall(CallInst *CI) { 317 IRBuilder<> Builder(CI->getParent(), CI); 318 319 Function *Callee = CI->getCalledFunction(); 320 assert(Callee && "Cannot lower an indirect call!"); 321 322 switch (Callee->getIntrinsicID()) { 323 case Intrinsic::not_intrinsic: 324 llvm_report_error("Cannot lower a call to a non-intrinsic function '"+ 325 Callee->getName() + "'!"); 326 default: 327 llvm_report_error("Code generator does not support intrinsic function '"+ 328 Callee->getName()+"'!"); 329 330 // The setjmp/longjmp intrinsics should only exist in the code if it was 331 // never optimized (ie, right out of the CFE), or if it has been hacked on 332 // by the lowerinvoke pass. In both cases, the right thing to do is to 333 // convert the call to an explicit setjmp or longjmp call. 334 case Intrinsic::setjmp: { 335 Value *V = ReplaceCallWith("setjmp", CI, CI->op_begin() + 1, CI->op_end(), 336 Type::Int32Ty); 337 if (CI->getType() != Type::VoidTy) 338 CI->replaceAllUsesWith(V); 339 break; 340 } 341 case Intrinsic::sigsetjmp: 342 if (CI->getType() != Type::VoidTy) 343 CI->replaceAllUsesWith(Constant::getNullValue(CI->getType())); 344 break; 345 346 case Intrinsic::longjmp: { 347 ReplaceCallWith("longjmp", CI, CI->op_begin() + 1, CI->op_end(), 348 Type::VoidTy); 349 break; 350 } 351 352 case Intrinsic::siglongjmp: { 353 // Insert the call to abort 354 ReplaceCallWith("abort", CI, CI->op_end(), CI->op_end(), 355 Type::VoidTy); 356 break; 357 } 358 case Intrinsic::ctpop: 359 CI->replaceAllUsesWith(LowerCTPOP(CI->getOperand(1), CI)); 360 break; 361 362 case Intrinsic::bswap: 363 CI->replaceAllUsesWith(LowerBSWAP(CI->getOperand(1), CI)); 364 break; 365 366 case Intrinsic::ctlz: 367 CI->replaceAllUsesWith(LowerCTLZ(CI->getOperand(1), CI)); 368 break; 369 370 case Intrinsic::cttz: { 371 // cttz(x) -> ctpop(~X & (X-1)) 372 Value *Src = CI->getOperand(1); 373 Value *NotSrc = Builder.CreateNot(Src); 374 NotSrc->setName(Src->getName() + ".not"); 375 Value *SrcM1 = ConstantInt::get(Src->getType(), 1); 376 SrcM1 = Builder.CreateSub(Src, SrcM1); 377 Src = LowerCTPOP(Builder.CreateAnd(NotSrc, SrcM1), CI); 378 CI->replaceAllUsesWith(Src); 379 break; 380 } 381 382 case Intrinsic::stacksave: 383 case Intrinsic::stackrestore: { 384 if (!Warned) 385 cerr << "WARNING: this target does not support the llvm.stack" 386 << (Callee->getIntrinsicID() == Intrinsic::stacksave ? 387 "save" : "restore") << " intrinsic.\n"; 388 Warned = true; 389 if (Callee->getIntrinsicID() == Intrinsic::stacksave) 390 CI->replaceAllUsesWith(Constant::getNullValue(CI->getType())); 391 break; 392 } 393 394 case Intrinsic::returnaddress: 395 case Intrinsic::frameaddress: 396 cerr << "WARNING: this target does not support the llvm." 397 << (Callee->getIntrinsicID() == Intrinsic::returnaddress ? 398 "return" : "frame") << "address intrinsic.\n"; 399 CI->replaceAllUsesWith(ConstantPointerNull::get( 400 cast<PointerType>(CI->getType()))); 401 break; 402 403 case Intrinsic::prefetch: 404 break; // Simply strip out prefetches on unsupported architectures 405 406 case Intrinsic::pcmarker: 407 break; // Simply strip out pcmarker on unsupported architectures 408 case Intrinsic::readcyclecounter: { 409 cerr << "WARNING: this target does not support the llvm.readcyclecoun" 410 << "ter intrinsic. It is being lowered to a constant 0\n"; 411 CI->replaceAllUsesWith(ConstantInt::get(Type::Int64Ty, 0)); 412 break; 413 } 414 415 case Intrinsic::dbg_stoppoint: 416 case Intrinsic::dbg_region_start: 417 case Intrinsic::dbg_region_end: 418 case Intrinsic::dbg_func_start: 419 case Intrinsic::dbg_declare: 420 break; // Simply strip out debugging intrinsics 421 422 case Intrinsic::eh_exception: 423 case Intrinsic::eh_selector_i32: 424 case Intrinsic::eh_selector_i64: 425 CI->replaceAllUsesWith(Constant::getNullValue(CI->getType())); 426 break; 427 428 case Intrinsic::eh_typeid_for_i32: 429 case Intrinsic::eh_typeid_for_i64: 430 // Return something different to eh_selector. 431 CI->replaceAllUsesWith(ConstantInt::get(CI->getType(), 1)); 432 break; 433 434 case Intrinsic::var_annotation: 435 break; // Strip out annotate intrinsic 436 437 case Intrinsic::memcpy: { 438 const IntegerType *IntPtr = TD.getIntPtrType(); 439 Value *Size = Builder.CreateIntCast(CI->getOperand(3), IntPtr, 440 /* isSigned */ false); 441 Value *Ops[3]; 442 Ops[0] = CI->getOperand(1); 443 Ops[1] = CI->getOperand(2); 444 Ops[2] = Size; 445 ReplaceCallWith("memcpy", CI, Ops, Ops+3, CI->getOperand(1)->getType()); 446 break; 447 } 448 case Intrinsic::memmove: { 449 const IntegerType *IntPtr = TD.getIntPtrType(); 450 Value *Size = Builder.CreateIntCast(CI->getOperand(3), IntPtr, 451 /* isSigned */ false); 452 Value *Ops[3]; 453 Ops[0] = CI->getOperand(1); 454 Ops[1] = CI->getOperand(2); 455 Ops[2] = Size; 456 ReplaceCallWith("memmove", CI, Ops, Ops+3, CI->getOperand(1)->getType()); 457 break; 458 } 459 case Intrinsic::memset: { 460 const IntegerType *IntPtr = TD.getIntPtrType(); 461 Value *Size = Builder.CreateIntCast(CI->getOperand(3), IntPtr, 462 /* isSigned */ false); 463 Value *Ops[3]; 464 Ops[0] = CI->getOperand(1); 465 // Extend the amount to i32. 466 Ops[1] = Builder.CreateIntCast(CI->getOperand(2), Type::Int32Ty, 467 /* isSigned */ false); 468 Ops[2] = Size; 469 ReplaceCallWith("memset", CI, Ops, Ops+3, CI->getOperand(1)->getType()); 470 break; 471 } 472 case Intrinsic::sqrt: { 473 ReplaceFPIntrinsicWithCall(CI, "sqrtf", "sqrt", "sqrtl"); 474 break; 475 } 476 case Intrinsic::log: { 477 ReplaceFPIntrinsicWithCall(CI, "logf", "log", "logl"); 478 break; 479 } 480 case Intrinsic::log2: { 481 ReplaceFPIntrinsicWithCall(CI, "log2f", "log2", "log2l"); 482 break; 483 } 484 case Intrinsic::log10: { 485 ReplaceFPIntrinsicWithCall(CI, "log10f", "log10", "log10l"); 486 break; 487 } 488 case Intrinsic::exp: { 489 ReplaceFPIntrinsicWithCall(CI, "expf", "exp", "expl"); 490 break; 491 } 492 case Intrinsic::exp2: { 493 ReplaceFPIntrinsicWithCall(CI, "exp2f", "exp2", "exp2l"); 494 break; 495 } 496 case Intrinsic::pow: { 497 ReplaceFPIntrinsicWithCall(CI, "powf", "pow", "powl"); 498 break; 499 } 500 case Intrinsic::flt_rounds: 501 // Lower to "round to the nearest" 502 if (CI->getType() != Type::VoidTy) 503 CI->replaceAllUsesWith(ConstantInt::get(CI->getType(), 1)); 504 break; 505 } 506 507 assert(CI->use_empty() && 508 "Lowering should have eliminated any uses of the intrinsic call!"); 509 CI->eraseFromParent(); 510} 511