1 //===- BuildLibCalls.cpp - Utility builder for libcalls -------------------===// 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 some functions that will create standard C libcalls. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/Transforms/Utils/BuildLibCalls.h" 15 #include "llvm/ADT/SmallString.h" 16 #include "llvm/IR/Constants.h" 17 #include "llvm/IR/DataLayout.h" 18 #include "llvm/IR/Function.h" 19 #include "llvm/IR/IRBuilder.h" 20 #include "llvm/IR/Intrinsics.h" 21 #include "llvm/IR/LLVMContext.h" 22 #include "llvm/IR/Module.h" 23 #include "llvm/IR/Type.h" 24 #include "llvm/Target/TargetLibraryInfo.h" 25 26 using namespace llvm; 27 28 /// CastToCStr - Return V if it is an i8*, otherwise cast it to i8*. 29 Value *llvm::CastToCStr(Value *V, IRBuilder<> &B) { 30 unsigned AS = V->getType()->getPointerAddressSpace(); 31 return B.CreateBitCast(V, B.getInt8PtrTy(AS), "cstr"); 32 } 33 34 /// EmitStrLen - Emit a call to the strlen function to the builder, for the 35 /// specified pointer. This always returns an integer value of size intptr_t. 36 Value *llvm::EmitStrLen(Value *Ptr, IRBuilder<> &B, const DataLayout *TD, 37 const TargetLibraryInfo *TLI) { 38 if (!TLI->has(LibFunc::strlen)) 39 return nullptr; 40 41 Module *M = B.GetInsertBlock()->getParent()->getParent(); 42 AttributeSet AS[2]; 43 AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture); 44 Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind }; 45 AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 46 ArrayRef<Attribute::AttrKind>(AVs, 2)); 47 48 LLVMContext &Context = B.GetInsertBlock()->getContext(); 49 Constant *StrLen = M->getOrInsertFunction("strlen", 50 AttributeSet::get(M->getContext(), 51 AS), 52 TD->getIntPtrType(Context), 53 B.getInt8PtrTy(), 54 NULL); 55 CallInst *CI = B.CreateCall(StrLen, CastToCStr(Ptr, B), "strlen"); 56 if (const Function *F = dyn_cast<Function>(StrLen->stripPointerCasts())) 57 CI->setCallingConv(F->getCallingConv()); 58 59 return CI; 60 } 61 62 /// EmitStrNLen - Emit a call to the strnlen function to the builder, for the 63 /// specified pointer. Ptr is required to be some pointer type, MaxLen must 64 /// be of size_t type, and the return value has 'intptr_t' type. 65 Value *llvm::EmitStrNLen(Value *Ptr, Value *MaxLen, IRBuilder<> &B, 66 const DataLayout *TD, const TargetLibraryInfo *TLI) { 67 if (!TLI->has(LibFunc::strnlen)) 68 return nullptr; 69 70 Module *M = B.GetInsertBlock()->getParent()->getParent(); 71 AttributeSet AS[2]; 72 AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture); 73 Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind }; 74 AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 75 ArrayRef<Attribute::AttrKind>(AVs, 2)); 76 77 LLVMContext &Context = B.GetInsertBlock()->getContext(); 78 Constant *StrNLen = M->getOrInsertFunction("strnlen", 79 AttributeSet::get(M->getContext(), 80 AS), 81 TD->getIntPtrType(Context), 82 B.getInt8PtrTy(), 83 TD->getIntPtrType(Context), 84 NULL); 85 CallInst *CI = B.CreateCall2(StrNLen, CastToCStr(Ptr, B), MaxLen, "strnlen"); 86 if (const Function *F = dyn_cast<Function>(StrNLen->stripPointerCasts())) 87 CI->setCallingConv(F->getCallingConv()); 88 89 return CI; 90 } 91 92 /// EmitStrChr - Emit a call to the strchr function to the builder, for the 93 /// specified pointer and character. Ptr is required to be some pointer type, 94 /// and the return value has 'i8*' type. 95 Value *llvm::EmitStrChr(Value *Ptr, char C, IRBuilder<> &B, 96 const DataLayout *TD, const TargetLibraryInfo *TLI) { 97 if (!TLI->has(LibFunc::strchr)) 98 return nullptr; 99 100 Module *M = B.GetInsertBlock()->getParent()->getParent(); 101 Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind }; 102 AttributeSet AS = 103 AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 104 ArrayRef<Attribute::AttrKind>(AVs, 2)); 105 106 Type *I8Ptr = B.getInt8PtrTy(); 107 Type *I32Ty = B.getInt32Ty(); 108 Constant *StrChr = M->getOrInsertFunction("strchr", 109 AttributeSet::get(M->getContext(), 110 AS), 111 I8Ptr, I8Ptr, I32Ty, NULL); 112 CallInst *CI = B.CreateCall2(StrChr, CastToCStr(Ptr, B), 113 ConstantInt::get(I32Ty, C), "strchr"); 114 if (const Function *F = dyn_cast<Function>(StrChr->stripPointerCasts())) 115 CI->setCallingConv(F->getCallingConv()); 116 return CI; 117 } 118 119 /// EmitStrNCmp - Emit a call to the strncmp function to the builder. 120 Value *llvm::EmitStrNCmp(Value *Ptr1, Value *Ptr2, Value *Len, 121 IRBuilder<> &B, const DataLayout *TD, 122 const TargetLibraryInfo *TLI) { 123 if (!TLI->has(LibFunc::strncmp)) 124 return nullptr; 125 126 Module *M = B.GetInsertBlock()->getParent()->getParent(); 127 AttributeSet AS[3]; 128 AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture); 129 AS[1] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture); 130 Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind }; 131 AS[2] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 132 ArrayRef<Attribute::AttrKind>(AVs, 2)); 133 134 LLVMContext &Context = B.GetInsertBlock()->getContext(); 135 Value *StrNCmp = M->getOrInsertFunction("strncmp", 136 AttributeSet::get(M->getContext(), 137 AS), 138 B.getInt32Ty(), 139 B.getInt8PtrTy(), 140 B.getInt8PtrTy(), 141 TD->getIntPtrType(Context), NULL); 142 CallInst *CI = B.CreateCall3(StrNCmp, CastToCStr(Ptr1, B), 143 CastToCStr(Ptr2, B), Len, "strncmp"); 144 145 if (const Function *F = dyn_cast<Function>(StrNCmp->stripPointerCasts())) 146 CI->setCallingConv(F->getCallingConv()); 147 148 return CI; 149 } 150 151 /// EmitStrCpy - Emit a call to the strcpy function to the builder, for the 152 /// specified pointer arguments. 153 Value *llvm::EmitStrCpy(Value *Dst, Value *Src, IRBuilder<> &B, 154 const DataLayout *TD, const TargetLibraryInfo *TLI, 155 StringRef Name) { 156 if (!TLI->has(LibFunc::strcpy)) 157 return nullptr; 158 159 Module *M = B.GetInsertBlock()->getParent()->getParent(); 160 AttributeSet AS[2]; 161 AS[0] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture); 162 AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 163 Attribute::NoUnwind); 164 Type *I8Ptr = B.getInt8PtrTy(); 165 Value *StrCpy = M->getOrInsertFunction(Name, 166 AttributeSet::get(M->getContext(), AS), 167 I8Ptr, I8Ptr, I8Ptr, NULL); 168 CallInst *CI = B.CreateCall2(StrCpy, CastToCStr(Dst, B), CastToCStr(Src, B), 169 Name); 170 if (const Function *F = dyn_cast<Function>(StrCpy->stripPointerCasts())) 171 CI->setCallingConv(F->getCallingConv()); 172 return CI; 173 } 174 175 /// EmitStrNCpy - Emit a call to the strncpy function to the builder, for the 176 /// specified pointer arguments. 177 Value *llvm::EmitStrNCpy(Value *Dst, Value *Src, Value *Len, 178 IRBuilder<> &B, const DataLayout *TD, 179 const TargetLibraryInfo *TLI, StringRef Name) { 180 if (!TLI->has(LibFunc::strncpy)) 181 return nullptr; 182 183 Module *M = B.GetInsertBlock()->getParent()->getParent(); 184 AttributeSet AS[2]; 185 AS[0] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture); 186 AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 187 Attribute::NoUnwind); 188 Type *I8Ptr = B.getInt8PtrTy(); 189 Value *StrNCpy = M->getOrInsertFunction(Name, 190 AttributeSet::get(M->getContext(), 191 AS), 192 I8Ptr, I8Ptr, I8Ptr, 193 Len->getType(), NULL); 194 CallInst *CI = B.CreateCall3(StrNCpy, CastToCStr(Dst, B), CastToCStr(Src, B), 195 Len, "strncpy"); 196 if (const Function *F = dyn_cast<Function>(StrNCpy->stripPointerCasts())) 197 CI->setCallingConv(F->getCallingConv()); 198 return CI; 199 } 200 201 /// EmitMemCpyChk - Emit a call to the __memcpy_chk function to the builder. 202 /// This expects that the Len and ObjSize have type 'intptr_t' and Dst/Src 203 /// are pointers. 204 Value *llvm::EmitMemCpyChk(Value *Dst, Value *Src, Value *Len, Value *ObjSize, 205 IRBuilder<> &B, const DataLayout *TD, 206 const TargetLibraryInfo *TLI) { 207 if (!TLI->has(LibFunc::memcpy_chk)) 208 return nullptr; 209 210 Module *M = B.GetInsertBlock()->getParent()->getParent(); 211 AttributeSet AS; 212 AS = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 213 Attribute::NoUnwind); 214 LLVMContext &Context = B.GetInsertBlock()->getContext(); 215 Value *MemCpy = M->getOrInsertFunction("__memcpy_chk", 216 AttributeSet::get(M->getContext(), AS), 217 B.getInt8PtrTy(), 218 B.getInt8PtrTy(), 219 B.getInt8PtrTy(), 220 TD->getIntPtrType(Context), 221 TD->getIntPtrType(Context), NULL); 222 Dst = CastToCStr(Dst, B); 223 Src = CastToCStr(Src, B); 224 CallInst *CI = B.CreateCall4(MemCpy, Dst, Src, Len, ObjSize); 225 if (const Function *F = dyn_cast<Function>(MemCpy->stripPointerCasts())) 226 CI->setCallingConv(F->getCallingConv()); 227 return CI; 228 } 229 230 /// EmitMemChr - Emit a call to the memchr function. This assumes that Ptr is 231 /// a pointer, Val is an i32 value, and Len is an 'intptr_t' value. 232 Value *llvm::EmitMemChr(Value *Ptr, Value *Val, 233 Value *Len, IRBuilder<> &B, const DataLayout *TD, 234 const TargetLibraryInfo *TLI) { 235 if (!TLI->has(LibFunc::memchr)) 236 return nullptr; 237 238 Module *M = B.GetInsertBlock()->getParent()->getParent(); 239 AttributeSet AS; 240 Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind }; 241 AS = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 242 ArrayRef<Attribute::AttrKind>(AVs, 2)); 243 LLVMContext &Context = B.GetInsertBlock()->getContext(); 244 Value *MemChr = M->getOrInsertFunction("memchr", 245 AttributeSet::get(M->getContext(), AS), 246 B.getInt8PtrTy(), 247 B.getInt8PtrTy(), 248 B.getInt32Ty(), 249 TD->getIntPtrType(Context), 250 NULL); 251 CallInst *CI = B.CreateCall3(MemChr, CastToCStr(Ptr, B), Val, Len, "memchr"); 252 253 if (const Function *F = dyn_cast<Function>(MemChr->stripPointerCasts())) 254 CI->setCallingConv(F->getCallingConv()); 255 256 return CI; 257 } 258 259 /// EmitMemCmp - Emit a call to the memcmp function. 260 Value *llvm::EmitMemCmp(Value *Ptr1, Value *Ptr2, 261 Value *Len, IRBuilder<> &B, const DataLayout *TD, 262 const TargetLibraryInfo *TLI) { 263 if (!TLI->has(LibFunc::memcmp)) 264 return nullptr; 265 266 Module *M = B.GetInsertBlock()->getParent()->getParent(); 267 AttributeSet AS[3]; 268 AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture); 269 AS[1] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture); 270 Attribute::AttrKind AVs[2] = { Attribute::ReadOnly, Attribute::NoUnwind }; 271 AS[2] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 272 ArrayRef<Attribute::AttrKind>(AVs, 2)); 273 274 LLVMContext &Context = B.GetInsertBlock()->getContext(); 275 Value *MemCmp = M->getOrInsertFunction("memcmp", 276 AttributeSet::get(M->getContext(), AS), 277 B.getInt32Ty(), 278 B.getInt8PtrTy(), 279 B.getInt8PtrTy(), 280 TD->getIntPtrType(Context), NULL); 281 CallInst *CI = B.CreateCall3(MemCmp, CastToCStr(Ptr1, B), CastToCStr(Ptr2, B), 282 Len, "memcmp"); 283 284 if (const Function *F = dyn_cast<Function>(MemCmp->stripPointerCasts())) 285 CI->setCallingConv(F->getCallingConv()); 286 287 return CI; 288 } 289 290 /// Append a suffix to the function name according to the type of 'Op'. 291 static void AppendTypeSuffix(Value *Op, StringRef &Name, SmallString<20> &NameBuffer) { 292 if (!Op->getType()->isDoubleTy()) { 293 NameBuffer += Name; 294 295 if (Op->getType()->isFloatTy()) 296 NameBuffer += 'f'; 297 else 298 NameBuffer += 'l'; 299 300 Name = NameBuffer; 301 } 302 return; 303 } 304 305 /// EmitUnaryFloatFnCall - Emit a call to the unary function named 'Name' (e.g. 306 /// 'floor'). This function is known to take a single of type matching 'Op' and 307 /// returns one value with the same type. If 'Op' is a long double, 'l' is 308 /// added as the suffix of name, if 'Op' is a float, we add a 'f' suffix. 309 Value *llvm::EmitUnaryFloatFnCall(Value *Op, StringRef Name, IRBuilder<> &B, 310 const AttributeSet &Attrs) { 311 SmallString<20> NameBuffer; 312 AppendTypeSuffix(Op, Name, NameBuffer); 313 314 Module *M = B.GetInsertBlock()->getParent()->getParent(); 315 Value *Callee = M->getOrInsertFunction(Name, Op->getType(), 316 Op->getType(), NULL); 317 CallInst *CI = B.CreateCall(Callee, Op, Name); 318 CI->setAttributes(Attrs); 319 if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts())) 320 CI->setCallingConv(F->getCallingConv()); 321 322 return CI; 323 } 324 325 /// EmitBinaryFloatFnCall - Emit a call to the binary function named 'Name' 326 /// (e.g. 'fmin'). This function is known to take type matching 'Op1' and 'Op2' 327 /// and return one value with the same type. If 'Op1/Op2' are long double, 'l' 328 /// is added as the suffix of name, if 'Op1/Op2' is a float, we add a 'f' 329 /// suffix. 330 Value *llvm::EmitBinaryFloatFnCall(Value *Op1, Value *Op2, StringRef Name, 331 IRBuilder<> &B, const AttributeSet &Attrs) { 332 SmallString<20> NameBuffer; 333 AppendTypeSuffix(Op1, Name, NameBuffer); 334 335 Module *M = B.GetInsertBlock()->getParent()->getParent(); 336 Value *Callee = M->getOrInsertFunction(Name, Op1->getType(), 337 Op1->getType(), Op2->getType(), NULL); 338 CallInst *CI = B.CreateCall2(Callee, Op1, Op2, Name); 339 CI->setAttributes(Attrs); 340 if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts())) 341 CI->setCallingConv(F->getCallingConv()); 342 343 return CI; 344 } 345 346 /// EmitPutChar - Emit a call to the putchar function. This assumes that Char 347 /// is an integer. 348 Value *llvm::EmitPutChar(Value *Char, IRBuilder<> &B, const DataLayout *TD, 349 const TargetLibraryInfo *TLI) { 350 if (!TLI->has(LibFunc::putchar)) 351 return nullptr; 352 353 Module *M = B.GetInsertBlock()->getParent()->getParent(); 354 Value *PutChar = M->getOrInsertFunction("putchar", B.getInt32Ty(), 355 B.getInt32Ty(), NULL); 356 CallInst *CI = B.CreateCall(PutChar, 357 B.CreateIntCast(Char, 358 B.getInt32Ty(), 359 /*isSigned*/true, 360 "chari"), 361 "putchar"); 362 363 if (const Function *F = dyn_cast<Function>(PutChar->stripPointerCasts())) 364 CI->setCallingConv(F->getCallingConv()); 365 return CI; 366 } 367 368 /// EmitPutS - Emit a call to the puts function. This assumes that Str is 369 /// some pointer. 370 Value *llvm::EmitPutS(Value *Str, IRBuilder<> &B, const DataLayout *TD, 371 const TargetLibraryInfo *TLI) { 372 if (!TLI->has(LibFunc::puts)) 373 return nullptr; 374 375 Module *M = B.GetInsertBlock()->getParent()->getParent(); 376 AttributeSet AS[2]; 377 AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture); 378 AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 379 Attribute::NoUnwind); 380 381 Value *PutS = M->getOrInsertFunction("puts", 382 AttributeSet::get(M->getContext(), AS), 383 B.getInt32Ty(), 384 B.getInt8PtrTy(), 385 NULL); 386 CallInst *CI = B.CreateCall(PutS, CastToCStr(Str, B), "puts"); 387 if (const Function *F = dyn_cast<Function>(PutS->stripPointerCasts())) 388 CI->setCallingConv(F->getCallingConv()); 389 return CI; 390 } 391 392 /// EmitFPutC - Emit a call to the fputc function. This assumes that Char is 393 /// an integer and File is a pointer to FILE. 394 Value *llvm::EmitFPutC(Value *Char, Value *File, IRBuilder<> &B, 395 const DataLayout *TD, const TargetLibraryInfo *TLI) { 396 if (!TLI->has(LibFunc::fputc)) 397 return nullptr; 398 399 Module *M = B.GetInsertBlock()->getParent()->getParent(); 400 AttributeSet AS[2]; 401 AS[0] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture); 402 AS[1] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 403 Attribute::NoUnwind); 404 Constant *F; 405 if (File->getType()->isPointerTy()) 406 F = M->getOrInsertFunction("fputc", 407 AttributeSet::get(M->getContext(), AS), 408 B.getInt32Ty(), 409 B.getInt32Ty(), File->getType(), 410 NULL); 411 else 412 F = M->getOrInsertFunction("fputc", 413 B.getInt32Ty(), 414 B.getInt32Ty(), 415 File->getType(), NULL); 416 Char = B.CreateIntCast(Char, B.getInt32Ty(), /*isSigned*/true, 417 "chari"); 418 CallInst *CI = B.CreateCall2(F, Char, File, "fputc"); 419 420 if (const Function *Fn = dyn_cast<Function>(F->stripPointerCasts())) 421 CI->setCallingConv(Fn->getCallingConv()); 422 return CI; 423 } 424 425 /// EmitFPutS - Emit a call to the puts function. Str is required to be a 426 /// pointer and File is a pointer to FILE. 427 Value *llvm::EmitFPutS(Value *Str, Value *File, IRBuilder<> &B, 428 const DataLayout *TD, const TargetLibraryInfo *TLI) { 429 if (!TLI->has(LibFunc::fputs)) 430 return nullptr; 431 432 Module *M = B.GetInsertBlock()->getParent()->getParent(); 433 AttributeSet AS[3]; 434 AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture); 435 AS[1] = AttributeSet::get(M->getContext(), 2, Attribute::NoCapture); 436 AS[2] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 437 Attribute::NoUnwind); 438 StringRef FPutsName = TLI->getName(LibFunc::fputs); 439 Constant *F; 440 if (File->getType()->isPointerTy()) 441 F = M->getOrInsertFunction(FPutsName, 442 AttributeSet::get(M->getContext(), AS), 443 B.getInt32Ty(), 444 B.getInt8PtrTy(), 445 File->getType(), NULL); 446 else 447 F = M->getOrInsertFunction(FPutsName, B.getInt32Ty(), 448 B.getInt8PtrTy(), 449 File->getType(), NULL); 450 CallInst *CI = B.CreateCall2(F, CastToCStr(Str, B), File, "fputs"); 451 452 if (const Function *Fn = dyn_cast<Function>(F->stripPointerCasts())) 453 CI->setCallingConv(Fn->getCallingConv()); 454 return CI; 455 } 456 457 /// EmitFWrite - Emit a call to the fwrite function. This assumes that Ptr is 458 /// a pointer, Size is an 'intptr_t', and File is a pointer to FILE. 459 Value *llvm::EmitFWrite(Value *Ptr, Value *Size, Value *File, 460 IRBuilder<> &B, const DataLayout *TD, 461 const TargetLibraryInfo *TLI) { 462 if (!TLI->has(LibFunc::fwrite)) 463 return nullptr; 464 465 Module *M = B.GetInsertBlock()->getParent()->getParent(); 466 AttributeSet AS[3]; 467 AS[0] = AttributeSet::get(M->getContext(), 1, Attribute::NoCapture); 468 AS[1] = AttributeSet::get(M->getContext(), 4, Attribute::NoCapture); 469 AS[2] = AttributeSet::get(M->getContext(), AttributeSet::FunctionIndex, 470 Attribute::NoUnwind); 471 LLVMContext &Context = B.GetInsertBlock()->getContext(); 472 StringRef FWriteName = TLI->getName(LibFunc::fwrite); 473 Constant *F; 474 if (File->getType()->isPointerTy()) 475 F = M->getOrInsertFunction(FWriteName, 476 AttributeSet::get(M->getContext(), AS), 477 TD->getIntPtrType(Context), 478 B.getInt8PtrTy(), 479 TD->getIntPtrType(Context), 480 TD->getIntPtrType(Context), 481 File->getType(), NULL); 482 else 483 F = M->getOrInsertFunction(FWriteName, TD->getIntPtrType(Context), 484 B.getInt8PtrTy(), 485 TD->getIntPtrType(Context), 486 TD->getIntPtrType(Context), 487 File->getType(), NULL); 488 CallInst *CI = B.CreateCall4(F, CastToCStr(Ptr, B), Size, 489 ConstantInt::get(TD->getIntPtrType(Context), 1), File); 490 491 if (const Function *Fn = dyn_cast<Function>(F->stripPointerCasts())) 492 CI->setCallingConv(Fn->getCallingConv()); 493 return CI; 494 } 495 496 SimplifyFortifiedLibCalls::~SimplifyFortifiedLibCalls() { } 497 498 bool SimplifyFortifiedLibCalls::fold(CallInst *CI, const DataLayout *TD, 499 const TargetLibraryInfo *TLI) { 500 // We really need DataLayout for later. 501 if (!TD) return false; 502 503 this->CI = CI; 504 Function *Callee = CI->getCalledFunction(); 505 StringRef Name = Callee->getName(); 506 FunctionType *FT = Callee->getFunctionType(); 507 LLVMContext &Context = CI->getParent()->getContext(); 508 IRBuilder<> B(CI); 509 510 if (Name == "__memcpy_chk") { 511 // Check if this has the right signature. 512 if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) || 513 !FT->getParamType(0)->isPointerTy() || 514 !FT->getParamType(1)->isPointerTy() || 515 FT->getParamType(2) != TD->getIntPtrType(Context) || 516 FT->getParamType(3) != TD->getIntPtrType(Context)) 517 return false; 518 519 if (isFoldable(3, 2, false)) { 520 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1), 521 CI->getArgOperand(2), 1); 522 replaceCall(CI->getArgOperand(0)); 523 return true; 524 } 525 return false; 526 } 527 528 // Should be similar to memcpy. 529 if (Name == "__mempcpy_chk") { 530 return false; 531 } 532 533 if (Name == "__memmove_chk") { 534 // Check if this has the right signature. 535 if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) || 536 !FT->getParamType(0)->isPointerTy() || 537 !FT->getParamType(1)->isPointerTy() || 538 FT->getParamType(2) != TD->getIntPtrType(Context) || 539 FT->getParamType(3) != TD->getIntPtrType(Context)) 540 return false; 541 542 if (isFoldable(3, 2, false)) { 543 B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1), 544 CI->getArgOperand(2), 1); 545 replaceCall(CI->getArgOperand(0)); 546 return true; 547 } 548 return false; 549 } 550 551 if (Name == "__memset_chk") { 552 // Check if this has the right signature. 553 if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) || 554 !FT->getParamType(0)->isPointerTy() || 555 !FT->getParamType(1)->isIntegerTy() || 556 FT->getParamType(2) != TD->getIntPtrType(Context) || 557 FT->getParamType(3) != TD->getIntPtrType(Context)) 558 return false; 559 560 if (isFoldable(3, 2, false)) { 561 Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), 562 false); 563 B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1); 564 replaceCall(CI->getArgOperand(0)); 565 return true; 566 } 567 return false; 568 } 569 570 if (Name == "__strcpy_chk" || Name == "__stpcpy_chk") { 571 // Check if this has the right signature. 572 if (FT->getNumParams() != 3 || 573 FT->getReturnType() != FT->getParamType(0) || 574 FT->getParamType(0) != FT->getParamType(1) || 575 FT->getParamType(0) != Type::getInt8PtrTy(Context) || 576 FT->getParamType(2) != TD->getIntPtrType(Context)) 577 return 0; 578 579 580 // If a) we don't have any length information, or b) we know this will 581 // fit then just lower to a plain st[rp]cpy. Otherwise we'll keep our 582 // st[rp]cpy_chk call which may fail at runtime if the size is too long. 583 // TODO: It might be nice to get a maximum length out of the possible 584 // string lengths for varying. 585 if (isFoldable(2, 1, true)) { 586 Value *Ret = EmitStrCpy(CI->getArgOperand(0), CI->getArgOperand(1), B, TD, 587 TLI, Name.substr(2, 6)); 588 if (!Ret) 589 return false; 590 replaceCall(Ret); 591 return true; 592 } 593 return false; 594 } 595 596 if (Name == "__strncpy_chk" || Name == "__stpncpy_chk") { 597 // Check if this has the right signature. 598 if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) || 599 FT->getParamType(0) != FT->getParamType(1) || 600 FT->getParamType(0) != Type::getInt8PtrTy(Context) || 601 !FT->getParamType(2)->isIntegerTy() || 602 FT->getParamType(3) != TD->getIntPtrType(Context)) 603 return false; 604 605 if (isFoldable(3, 2, false)) { 606 Value *Ret = EmitStrNCpy(CI->getArgOperand(0), CI->getArgOperand(1), 607 CI->getArgOperand(2), B, TD, TLI, 608 Name.substr(2, 7)); 609 if (!Ret) 610 return false; 611 replaceCall(Ret); 612 return true; 613 } 614 return false; 615 } 616 617 if (Name == "__strcat_chk") { 618 return false; 619 } 620 621 if (Name == "__strncat_chk") { 622 return false; 623 } 624 625 return false; 626 } 627
