TargetInfo.cpp revision eb518b4b89e4134b21975530809697142f69b779
1//===---- TargetInfo.cpp - Encapsulate target details -----------*- C++ -*-===// 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// These classes wrap the information about a call or function 11// definition used to handle ABI compliancy. 12// 13//===----------------------------------------------------------------------===// 14 15#include "TargetInfo.h" 16#include "ABIInfo.h" 17#include "CodeGenFunction.h" 18#include "clang/AST/RecordLayout.h" 19#include "llvm/Type.h" 20#include "llvm/Target/TargetData.h" 21#include "llvm/ADT/StringExtras.h" 22#include "llvm/ADT/Triple.h" 23#include "llvm/Support/raw_ostream.h" 24using namespace clang; 25using namespace CodeGen; 26 27static void AssignToArrayRange(CodeGen::CGBuilderTy &Builder, 28 llvm::Value *Array, 29 llvm::Value *Value, 30 unsigned FirstIndex, 31 unsigned LastIndex) { 32 // Alternatively, we could emit this as a loop in the source. 33 for (unsigned I = FirstIndex; I <= LastIndex; ++I) { 34 llvm::Value *Cell = Builder.CreateConstInBoundsGEP1_32(Array, I); 35 Builder.CreateStore(Value, Cell); 36 } 37} 38 39ABIInfo::~ABIInfo() {} 40 41ASTContext &ABIInfo::getContext() const { 42 return CGT.getContext(); 43} 44 45llvm::LLVMContext &ABIInfo::getVMContext() const { 46 return CGT.getLLVMContext(); 47} 48 49const llvm::TargetData &ABIInfo::getTargetData() const { 50 return CGT.getTargetData(); 51} 52 53 54void ABIArgInfo::dump() const { 55 llvm::raw_ostream &OS = llvm::errs(); 56 OS << "(ABIArgInfo Kind="; 57 switch (TheKind) { 58 case Direct: 59 OS << "Direct Type="; 60 if (const llvm::Type *Ty = getCoerceToType()) 61 Ty->print(OS); 62 else 63 OS << "null"; 64 break; 65 case Extend: 66 OS << "Extend"; 67 break; 68 case Ignore: 69 OS << "Ignore"; 70 break; 71 case Indirect: 72 OS << "Indirect Align=" << getIndirectAlign() 73 << " Byal=" << getIndirectByVal(); 74 break; 75 case Expand: 76 OS << "Expand"; 77 break; 78 } 79 OS << ")\n"; 80} 81 82TargetCodeGenInfo::~TargetCodeGenInfo() { delete Info; } 83 84static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays); 85 86/// isEmptyField - Return true iff a the field is "empty", that is it 87/// is an unnamed bit-field or an (array of) empty record(s). 88static bool isEmptyField(ASTContext &Context, const FieldDecl *FD, 89 bool AllowArrays) { 90 if (FD->isUnnamedBitfield()) 91 return true; 92 93 QualType FT = FD->getType(); 94 95 // Constant arrays of empty records count as empty, strip them off. 96 if (AllowArrays) 97 while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) 98 FT = AT->getElementType(); 99 100 const RecordType *RT = FT->getAs<RecordType>(); 101 if (!RT) 102 return false; 103 104 // C++ record fields are never empty, at least in the Itanium ABI. 105 // 106 // FIXME: We should use a predicate for whether this behavior is true in the 107 // current ABI. 108 if (isa<CXXRecordDecl>(RT->getDecl())) 109 return false; 110 111 return isEmptyRecord(Context, FT, AllowArrays); 112} 113 114/// isEmptyRecord - Return true iff a structure contains only empty 115/// fields. Note that a structure with a flexible array member is not 116/// considered empty. 117static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays) { 118 const RecordType *RT = T->getAs<RecordType>(); 119 if (!RT) 120 return 0; 121 const RecordDecl *RD = RT->getDecl(); 122 if (RD->hasFlexibleArrayMember()) 123 return false; 124 125 // If this is a C++ record, check the bases first. 126 if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) 127 for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(), 128 e = CXXRD->bases_end(); i != e; ++i) 129 if (!isEmptyRecord(Context, i->getType(), true)) 130 return false; 131 132 for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end(); 133 i != e; ++i) 134 if (!isEmptyField(Context, *i, AllowArrays)) 135 return false; 136 return true; 137} 138 139/// hasNonTrivialDestructorOrCopyConstructor - Determine if a type has either 140/// a non-trivial destructor or a non-trivial copy constructor. 141static bool hasNonTrivialDestructorOrCopyConstructor(const RecordType *RT) { 142 const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()); 143 if (!RD) 144 return false; 145 146 return !RD->hasTrivialDestructor() || !RD->hasTrivialCopyConstructor(); 147} 148 149/// isRecordWithNonTrivialDestructorOrCopyConstructor - Determine if a type is 150/// a record type with either a non-trivial destructor or a non-trivial copy 151/// constructor. 152static bool isRecordWithNonTrivialDestructorOrCopyConstructor(QualType T) { 153 const RecordType *RT = T->getAs<RecordType>(); 154 if (!RT) 155 return false; 156 157 return hasNonTrivialDestructorOrCopyConstructor(RT); 158} 159 160/// isSingleElementStruct - Determine if a structure is a "single 161/// element struct", i.e. it has exactly one non-empty field or 162/// exactly one field which is itself a single element 163/// struct. Structures with flexible array members are never 164/// considered single element structs. 165/// 166/// \return The field declaration for the single non-empty field, if 167/// it exists. 168static const Type *isSingleElementStruct(QualType T, ASTContext &Context) { 169 const RecordType *RT = T->getAsStructureType(); 170 if (!RT) 171 return 0; 172 173 const RecordDecl *RD = RT->getDecl(); 174 if (RD->hasFlexibleArrayMember()) 175 return 0; 176 177 const Type *Found = 0; 178 179 // If this is a C++ record, check the bases first. 180 if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) { 181 for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(), 182 e = CXXRD->bases_end(); i != e; ++i) { 183 // Ignore empty records. 184 if (isEmptyRecord(Context, i->getType(), true)) 185 continue; 186 187 // If we already found an element then this isn't a single-element struct. 188 if (Found) 189 return 0; 190 191 // If this is non-empty and not a single element struct, the composite 192 // cannot be a single element struct. 193 Found = isSingleElementStruct(i->getType(), Context); 194 if (!Found) 195 return 0; 196 } 197 } 198 199 // Check for single element. 200 for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end(); 201 i != e; ++i) { 202 const FieldDecl *FD = *i; 203 QualType FT = FD->getType(); 204 205 // Ignore empty fields. 206 if (isEmptyField(Context, FD, true)) 207 continue; 208 209 // If we already found an element then this isn't a single-element 210 // struct. 211 if (Found) 212 return 0; 213 214 // Treat single element arrays as the element. 215 while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) { 216 if (AT->getSize().getZExtValue() != 1) 217 break; 218 FT = AT->getElementType(); 219 } 220 221 if (!CodeGenFunction::hasAggregateLLVMType(FT)) { 222 Found = FT.getTypePtr(); 223 } else { 224 Found = isSingleElementStruct(FT, Context); 225 if (!Found) 226 return 0; 227 } 228 } 229 230 return Found; 231} 232 233static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) { 234 if (!Ty->getAs<BuiltinType>() && !Ty->hasPointerRepresentation() && 235 !Ty->isAnyComplexType() && !Ty->isEnumeralType() && 236 !Ty->isBlockPointerType()) 237 return false; 238 239 uint64_t Size = Context.getTypeSize(Ty); 240 return Size == 32 || Size == 64; 241} 242 243/// canExpandIndirectArgument - Test whether an argument type which is to be 244/// passed indirectly (on the stack) would have the equivalent layout if it was 245/// expanded into separate arguments. If so, we prefer to do the latter to avoid 246/// inhibiting optimizations. 247/// 248// FIXME: This predicate is missing many cases, currently it just follows 249// llvm-gcc (checks that all fields are 32-bit or 64-bit primitive types). We 250// should probably make this smarter, or better yet make the LLVM backend 251// capable of handling it. 252static bool canExpandIndirectArgument(QualType Ty, ASTContext &Context) { 253 // We can only expand structure types. 254 const RecordType *RT = Ty->getAs<RecordType>(); 255 if (!RT) 256 return false; 257 258 // We can only expand (C) structures. 259 // 260 // FIXME: This needs to be generalized to handle classes as well. 261 const RecordDecl *RD = RT->getDecl(); 262 if (!RD->isStruct() || isa<CXXRecordDecl>(RD)) 263 return false; 264 265 for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end(); 266 i != e; ++i) { 267 const FieldDecl *FD = *i; 268 269 if (!is32Or64BitBasicType(FD->getType(), Context)) 270 return false; 271 272 // FIXME: Reject bit-fields wholesale; there are two problems, we don't know 273 // how to expand them yet, and the predicate for telling if a bitfield still 274 // counts as "basic" is more complicated than what we were doing previously. 275 if (FD->isBitField()) 276 return false; 277 } 278 279 return true; 280} 281 282namespace { 283/// DefaultABIInfo - The default implementation for ABI specific 284/// details. This implementation provides information which results in 285/// self-consistent and sensible LLVM IR generation, but does not 286/// conform to any particular ABI. 287class DefaultABIInfo : public ABIInfo { 288public: 289 DefaultABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {} 290 291 ABIArgInfo classifyReturnType(QualType RetTy) const; 292 ABIArgInfo classifyArgumentType(QualType RetTy) const; 293 294 virtual void computeInfo(CGFunctionInfo &FI) const { 295 FI.getReturnInfo() = classifyReturnType(FI.getReturnType()); 296 for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end(); 297 it != ie; ++it) 298 it->info = classifyArgumentType(it->type); 299 } 300 301 virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 302 CodeGenFunction &CGF) const; 303}; 304 305class DefaultTargetCodeGenInfo : public TargetCodeGenInfo { 306public: 307 DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT) 308 : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {} 309}; 310 311llvm::Value *DefaultABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 312 CodeGenFunction &CGF) const { 313 return 0; 314} 315 316ABIArgInfo DefaultABIInfo::classifyArgumentType(QualType Ty) const { 317 if (CodeGenFunction::hasAggregateLLVMType(Ty)) 318 return ABIArgInfo::getIndirect(0); 319 320 // Treat an enum type as its underlying type. 321 if (const EnumType *EnumTy = Ty->getAs<EnumType>()) 322 Ty = EnumTy->getDecl()->getIntegerType(); 323 324 return (Ty->isPromotableIntegerType() ? 325 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 326} 327 328//===----------------------------------------------------------------------===// 329// X86-32 ABI Implementation 330//===----------------------------------------------------------------------===// 331 332/// X86_32ABIInfo - The X86-32 ABI information. 333class X86_32ABIInfo : public ABIInfo { 334 bool IsDarwinVectorABI; 335 bool IsSmallStructInRegABI; 336 337 static bool isRegisterSize(unsigned Size) { 338 return (Size == 8 || Size == 16 || Size == 32 || Size == 64); 339 } 340 341 static bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context); 342 343 /// getIndirectResult - Give a source type \arg Ty, return a suitable result 344 /// such that the argument will be passed in memory. 345 ABIArgInfo getIndirectResult(QualType Ty, bool ByVal = true) const; 346 347public: 348 349 ABIArgInfo classifyReturnType(QualType RetTy) const; 350 ABIArgInfo classifyArgumentType(QualType RetTy) const; 351 352 virtual void computeInfo(CGFunctionInfo &FI) const { 353 FI.getReturnInfo() = classifyReturnType(FI.getReturnType()); 354 for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end(); 355 it != ie; ++it) 356 it->info = classifyArgumentType(it->type); 357 } 358 359 virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 360 CodeGenFunction &CGF) const; 361 362 X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool d, bool p) 363 : ABIInfo(CGT), IsDarwinVectorABI(d), IsSmallStructInRegABI(p) {} 364}; 365 366class X86_32TargetCodeGenInfo : public TargetCodeGenInfo { 367public: 368 X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool d, bool p) 369 :TargetCodeGenInfo(new X86_32ABIInfo(CGT, d, p)) {} 370 371 void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV, 372 CodeGen::CodeGenModule &CGM) const; 373 374 int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const { 375 // Darwin uses different dwarf register numbers for EH. 376 if (CGM.isTargetDarwin()) return 5; 377 378 return 4; 379 } 380 381 bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF, 382 llvm::Value *Address) const; 383}; 384 385} 386 387/// shouldReturnTypeInRegister - Determine if the given type should be 388/// passed in a register (for the Darwin ABI). 389bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty, 390 ASTContext &Context) { 391 uint64_t Size = Context.getTypeSize(Ty); 392 393 // Type must be register sized. 394 if (!isRegisterSize(Size)) 395 return false; 396 397 if (Ty->isVectorType()) { 398 // 64- and 128- bit vectors inside structures are not returned in 399 // registers. 400 if (Size == 64 || Size == 128) 401 return false; 402 403 return true; 404 } 405 406 // If this is a builtin, pointer, enum, complex type, member pointer, or 407 // member function pointer it is ok. 408 if (Ty->getAs<BuiltinType>() || Ty->hasPointerRepresentation() || 409 Ty->isAnyComplexType() || Ty->isEnumeralType() || 410 Ty->isBlockPointerType() || Ty->isMemberPointerType()) 411 return true; 412 413 // Arrays are treated like records. 414 if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) 415 return shouldReturnTypeInRegister(AT->getElementType(), Context); 416 417 // Otherwise, it must be a record type. 418 const RecordType *RT = Ty->getAs<RecordType>(); 419 if (!RT) return false; 420 421 // FIXME: Traverse bases here too. 422 423 // Structure types are passed in register if all fields would be 424 // passed in a register. 425 for (RecordDecl::field_iterator i = RT->getDecl()->field_begin(), 426 e = RT->getDecl()->field_end(); i != e; ++i) { 427 const FieldDecl *FD = *i; 428 429 // Empty fields are ignored. 430 if (isEmptyField(Context, FD, true)) 431 continue; 432 433 // Check fields recursively. 434 if (!shouldReturnTypeInRegister(FD->getType(), Context)) 435 return false; 436 } 437 438 return true; 439} 440 441ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy) const { 442 if (RetTy->isVoidType()) 443 return ABIArgInfo::getIgnore(); 444 445 if (const VectorType *VT = RetTy->getAs<VectorType>()) { 446 // On Darwin, some vectors are returned in registers. 447 if (IsDarwinVectorABI) { 448 uint64_t Size = getContext().getTypeSize(RetTy); 449 450 // 128-bit vectors are a special case; they are returned in 451 // registers and we need to make sure to pick a type the LLVM 452 // backend will like. 453 if (Size == 128) 454 return ABIArgInfo::getDirect(llvm::VectorType::get( 455 llvm::Type::getInt64Ty(getVMContext()), 2)); 456 457 // Always return in register if it fits in a general purpose 458 // register, or if it is 64 bits and has a single element. 459 if ((Size == 8 || Size == 16 || Size == 32) || 460 (Size == 64 && VT->getNumElements() == 1)) 461 return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 462 Size)); 463 464 return ABIArgInfo::getIndirect(0); 465 } 466 467 return ABIArgInfo::getDirect(); 468 } 469 470 if (CodeGenFunction::hasAggregateLLVMType(RetTy)) { 471 if (const RecordType *RT = RetTy->getAs<RecordType>()) { 472 // Structures with either a non-trivial destructor or a non-trivial 473 // copy constructor are always indirect. 474 if (hasNonTrivialDestructorOrCopyConstructor(RT)) 475 return ABIArgInfo::getIndirect(0, /*ByVal=*/false); 476 477 // Structures with flexible arrays are always indirect. 478 if (RT->getDecl()->hasFlexibleArrayMember()) 479 return ABIArgInfo::getIndirect(0); 480 } 481 482 // If specified, structs and unions are always indirect. 483 if (!IsSmallStructInRegABI && !RetTy->isAnyComplexType()) 484 return ABIArgInfo::getIndirect(0); 485 486 // Classify "single element" structs as their element type. 487 if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext())) { 488 if (const BuiltinType *BT = SeltTy->getAs<BuiltinType>()) { 489 if (BT->isIntegerType()) { 490 // We need to use the size of the structure, padding 491 // bit-fields can adjust that to be larger than the single 492 // element type. 493 uint64_t Size = getContext().getTypeSize(RetTy); 494 return ABIArgInfo::getDirect( 495 llvm::IntegerType::get(getVMContext(), (unsigned)Size)); 496 } 497 498 if (BT->getKind() == BuiltinType::Float) { 499 assert(getContext().getTypeSize(RetTy) == 500 getContext().getTypeSize(SeltTy) && 501 "Unexpect single element structure size!"); 502 return ABIArgInfo::getDirect(llvm::Type::getFloatTy(getVMContext())); 503 } 504 505 if (BT->getKind() == BuiltinType::Double) { 506 assert(getContext().getTypeSize(RetTy) == 507 getContext().getTypeSize(SeltTy) && 508 "Unexpect single element structure size!"); 509 return ABIArgInfo::getDirect(llvm::Type::getDoubleTy(getVMContext())); 510 } 511 } else if (SeltTy->isPointerType()) { 512 // FIXME: It would be really nice if this could come out as the proper 513 // pointer type. 514 const llvm::Type *PtrTy = llvm::Type::getInt8PtrTy(getVMContext()); 515 return ABIArgInfo::getDirect(PtrTy); 516 } else if (SeltTy->isVectorType()) { 517 // 64- and 128-bit vectors are never returned in a 518 // register when inside a structure. 519 uint64_t Size = getContext().getTypeSize(RetTy); 520 if (Size == 64 || Size == 128) 521 return ABIArgInfo::getIndirect(0); 522 523 return classifyReturnType(QualType(SeltTy, 0)); 524 } 525 } 526 527 // Small structures which are register sized are generally returned 528 // in a register. 529 if (X86_32ABIInfo::shouldReturnTypeInRegister(RetTy, getContext())) { 530 uint64_t Size = getContext().getTypeSize(RetTy); 531 return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),Size)); 532 } 533 534 return ABIArgInfo::getIndirect(0); 535 } 536 537 // Treat an enum type as its underlying type. 538 if (const EnumType *EnumTy = RetTy->getAs<EnumType>()) 539 RetTy = EnumTy->getDecl()->getIntegerType(); 540 541 return (RetTy->isPromotableIntegerType() ? 542 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 543} 544 545ABIArgInfo X86_32ABIInfo::getIndirectResult(QualType Ty, bool ByVal) const { 546 if (!ByVal) 547 return ABIArgInfo::getIndirect(0, false); 548 549 // Compute the byval alignment. We trust the back-end to honor the 550 // minimum ABI alignment for byval, to make cleaner IR. 551 const unsigned MinABIAlign = 4; 552 unsigned Align = getContext().getTypeAlign(Ty) / 8; 553 if (Align > MinABIAlign) 554 return ABIArgInfo::getIndirect(Align); 555 return ABIArgInfo::getIndirect(0); 556} 557 558ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty) const { 559 // FIXME: Set alignment on indirect arguments. 560 if (CodeGenFunction::hasAggregateLLVMType(Ty)) { 561 // Structures with flexible arrays are always indirect. 562 if (const RecordType *RT = Ty->getAs<RecordType>()) { 563 // Structures with either a non-trivial destructor or a non-trivial 564 // copy constructor are always indirect. 565 if (hasNonTrivialDestructorOrCopyConstructor(RT)) 566 return getIndirectResult(Ty, /*ByVal=*/false); 567 568 if (RT->getDecl()->hasFlexibleArrayMember()) 569 return getIndirectResult(Ty); 570 } 571 572 // Ignore empty structs. 573 if (Ty->isStructureType() && getContext().getTypeSize(Ty) == 0) 574 return ABIArgInfo::getIgnore(); 575 576 // Expand small (<= 128-bit) record types when we know that the stack layout 577 // of those arguments will match the struct. This is important because the 578 // LLVM backend isn't smart enough to remove byval, which inhibits many 579 // optimizations. 580 if (getContext().getTypeSize(Ty) <= 4*32 && 581 canExpandIndirectArgument(Ty, getContext())) 582 return ABIArgInfo::getExpand(); 583 584 return getIndirectResult(Ty); 585 } 586 587 if (const EnumType *EnumTy = Ty->getAs<EnumType>()) 588 Ty = EnumTy->getDecl()->getIntegerType(); 589 590 return (Ty->isPromotableIntegerType() ? 591 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 592} 593 594llvm::Value *X86_32ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 595 CodeGenFunction &CGF) const { 596 const llvm::Type *BP = llvm::Type::getInt8PtrTy(CGF.getLLVMContext()); 597 const llvm::Type *BPP = llvm::PointerType::getUnqual(BP); 598 599 CGBuilderTy &Builder = CGF.Builder; 600 llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, 601 "ap"); 602 llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur"); 603 llvm::Type *PTy = 604 llvm::PointerType::getUnqual(CGF.ConvertType(Ty)); 605 llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy); 606 607 uint64_t Offset = 608 llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 4); 609 llvm::Value *NextAddr = 610 Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset), 611 "ap.next"); 612 Builder.CreateStore(NextAddr, VAListAddrAsBPP); 613 614 return AddrTyped; 615} 616 617void X86_32TargetCodeGenInfo::SetTargetAttributes(const Decl *D, 618 llvm::GlobalValue *GV, 619 CodeGen::CodeGenModule &CGM) const { 620 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 621 if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) { 622 // Get the LLVM function. 623 llvm::Function *Fn = cast<llvm::Function>(GV); 624 625 // Now add the 'alignstack' attribute with a value of 16. 626 Fn->addFnAttr(llvm::Attribute::constructStackAlignmentFromInt(16)); 627 } 628 } 629} 630 631bool X86_32TargetCodeGenInfo::initDwarfEHRegSizeTable( 632 CodeGen::CodeGenFunction &CGF, 633 llvm::Value *Address) const { 634 CodeGen::CGBuilderTy &Builder = CGF.Builder; 635 llvm::LLVMContext &Context = CGF.getLLVMContext(); 636 637 const llvm::IntegerType *i8 = llvm::Type::getInt8Ty(Context); 638 llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4); 639 640 // 0-7 are the eight integer registers; the order is different 641 // on Darwin (for EH), but the range is the same. 642 // 8 is %eip. 643 AssignToArrayRange(Builder, Address, Four8, 0, 8); 644 645 if (CGF.CGM.isTargetDarwin()) { 646 // 12-16 are st(0..4). Not sure why we stop at 4. 647 // These have size 16, which is sizeof(long double) on 648 // platforms with 8-byte alignment for that type. 649 llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16); 650 AssignToArrayRange(Builder, Address, Sixteen8, 12, 16); 651 652 } else { 653 // 9 is %eflags, which doesn't get a size on Darwin for some 654 // reason. 655 Builder.CreateStore(Four8, Builder.CreateConstInBoundsGEP1_32(Address, 9)); 656 657 // 11-16 are st(0..5). Not sure why we stop at 5. 658 // These have size 12, which is sizeof(long double) on 659 // platforms with 4-byte alignment for that type. 660 llvm::Value *Twelve8 = llvm::ConstantInt::get(i8, 12); 661 AssignToArrayRange(Builder, Address, Twelve8, 11, 16); 662 } 663 664 return false; 665} 666 667//===----------------------------------------------------------------------===// 668// X86-64 ABI Implementation 669//===----------------------------------------------------------------------===// 670 671 672namespace { 673/// X86_64ABIInfo - The X86_64 ABI information. 674class X86_64ABIInfo : public ABIInfo { 675 enum Class { 676 Integer = 0, 677 SSE, 678 SSEUp, 679 X87, 680 X87Up, 681 ComplexX87, 682 NoClass, 683 Memory 684 }; 685 686 /// merge - Implement the X86_64 ABI merging algorithm. 687 /// 688 /// Merge an accumulating classification \arg Accum with a field 689 /// classification \arg Field. 690 /// 691 /// \param Accum - The accumulating classification. This should 692 /// always be either NoClass or the result of a previous merge 693 /// call. In addition, this should never be Memory (the caller 694 /// should just return Memory for the aggregate). 695 static Class merge(Class Accum, Class Field); 696 697 /// classify - Determine the x86_64 register classes in which the 698 /// given type T should be passed. 699 /// 700 /// \param Lo - The classification for the parts of the type 701 /// residing in the low word of the containing object. 702 /// 703 /// \param Hi - The classification for the parts of the type 704 /// residing in the high word of the containing object. 705 /// 706 /// \param OffsetBase - The bit offset of this type in the 707 /// containing object. Some parameters are classified different 708 /// depending on whether they straddle an eightbyte boundary. 709 /// 710 /// If a word is unused its result will be NoClass; if a type should 711 /// be passed in Memory then at least the classification of \arg Lo 712 /// will be Memory. 713 /// 714 /// The \arg Lo class will be NoClass iff the argument is ignored. 715 /// 716 /// If the \arg Lo class is ComplexX87, then the \arg Hi class will 717 /// also be ComplexX87. 718 void classify(QualType T, uint64_t OffsetBase, Class &Lo, Class &Hi) const; 719 720 const llvm::Type *Get16ByteVectorType(QualType Ty) const; 721 const llvm::Type *GetSSETypeAtOffset(const llvm::Type *IRType, 722 unsigned IROffset, QualType SourceTy, 723 unsigned SourceOffset) const; 724 const llvm::Type *GetINTEGERTypeAtOffset(const llvm::Type *IRType, 725 unsigned IROffset, QualType SourceTy, 726 unsigned SourceOffset) const; 727 728 /// getIndirectResult - Give a source type \arg Ty, return a suitable result 729 /// such that the argument will be returned in memory. 730 ABIArgInfo getIndirectReturnResult(QualType Ty) const; 731 732 /// getIndirectResult - Give a source type \arg Ty, return a suitable result 733 /// such that the argument will be passed in memory. 734 ABIArgInfo getIndirectResult(QualType Ty) const; 735 736 ABIArgInfo classifyReturnType(QualType RetTy) const; 737 738 ABIArgInfo classifyArgumentType(QualType Ty, unsigned &neededInt, 739 unsigned &neededSSE) const; 740 741public: 742 X86_64ABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {} 743 744 virtual void computeInfo(CGFunctionInfo &FI) const; 745 746 virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 747 CodeGenFunction &CGF) const; 748}; 749 750class X86_64TargetCodeGenInfo : public TargetCodeGenInfo { 751public: 752 X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT) 753 : TargetCodeGenInfo(new X86_64ABIInfo(CGT)) {} 754 755 int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const { 756 return 7; 757 } 758 759 bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF, 760 llvm::Value *Address) const { 761 CodeGen::CGBuilderTy &Builder = CGF.Builder; 762 llvm::LLVMContext &Context = CGF.getLLVMContext(); 763 764 const llvm::IntegerType *i8 = llvm::Type::getInt8Ty(Context); 765 llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8); 766 767 // 0-15 are the 16 integer registers. 768 // 16 is %rip. 769 AssignToArrayRange(Builder, Address, Eight8, 0, 16); 770 771 return false; 772 } 773}; 774 775} 776 777X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) { 778 // AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is 779 // classified recursively so that always two fields are 780 // considered. The resulting class is calculated according to 781 // the classes of the fields in the eightbyte: 782 // 783 // (a) If both classes are equal, this is the resulting class. 784 // 785 // (b) If one of the classes is NO_CLASS, the resulting class is 786 // the other class. 787 // 788 // (c) If one of the classes is MEMORY, the result is the MEMORY 789 // class. 790 // 791 // (d) If one of the classes is INTEGER, the result is the 792 // INTEGER. 793 // 794 // (e) If one of the classes is X87, X87UP, COMPLEX_X87 class, 795 // MEMORY is used as class. 796 // 797 // (f) Otherwise class SSE is used. 798 799 // Accum should never be memory (we should have returned) or 800 // ComplexX87 (because this cannot be passed in a structure). 801 assert((Accum != Memory && Accum != ComplexX87) && 802 "Invalid accumulated classification during merge."); 803 if (Accum == Field || Field == NoClass) 804 return Accum; 805 if (Field == Memory) 806 return Memory; 807 if (Accum == NoClass) 808 return Field; 809 if (Accum == Integer || Field == Integer) 810 return Integer; 811 if (Field == X87 || Field == X87Up || Field == ComplexX87 || 812 Accum == X87 || Accum == X87Up) 813 return Memory; 814 return SSE; 815} 816 817void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase, 818 Class &Lo, Class &Hi) const { 819 // FIXME: This code can be simplified by introducing a simple value class for 820 // Class pairs with appropriate constructor methods for the various 821 // situations. 822 823 // FIXME: Some of the split computations are wrong; unaligned vectors 824 // shouldn't be passed in registers for example, so there is no chance they 825 // can straddle an eightbyte. Verify & simplify. 826 827 Lo = Hi = NoClass; 828 829 Class &Current = OffsetBase < 64 ? Lo : Hi; 830 Current = Memory; 831 832 if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) { 833 BuiltinType::Kind k = BT->getKind(); 834 835 if (k == BuiltinType::Void) { 836 Current = NoClass; 837 } else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) { 838 Lo = Integer; 839 Hi = Integer; 840 } else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) { 841 Current = Integer; 842 } else if (k == BuiltinType::Float || k == BuiltinType::Double) { 843 Current = SSE; 844 } else if (k == BuiltinType::LongDouble) { 845 Lo = X87; 846 Hi = X87Up; 847 } 848 // FIXME: _Decimal32 and _Decimal64 are SSE. 849 // FIXME: _float128 and _Decimal128 are (SSE, SSEUp). 850 return; 851 } 852 853 if (const EnumType *ET = Ty->getAs<EnumType>()) { 854 // Classify the underlying integer type. 855 classify(ET->getDecl()->getIntegerType(), OffsetBase, Lo, Hi); 856 return; 857 } 858 859 if (Ty->hasPointerRepresentation()) { 860 Current = Integer; 861 return; 862 } 863 864 if (Ty->isMemberPointerType()) { 865 if (Ty->isMemberFunctionPointerType()) 866 Lo = Hi = Integer; 867 else 868 Current = Integer; 869 return; 870 } 871 872 if (const VectorType *VT = Ty->getAs<VectorType>()) { 873 uint64_t Size = getContext().getTypeSize(VT); 874 if (Size == 32) { 875 // gcc passes all <4 x char>, <2 x short>, <1 x int>, <1 x 876 // float> as integer. 877 Current = Integer; 878 879 // If this type crosses an eightbyte boundary, it should be 880 // split. 881 uint64_t EB_Real = (OffsetBase) / 64; 882 uint64_t EB_Imag = (OffsetBase + Size - 1) / 64; 883 if (EB_Real != EB_Imag) 884 Hi = Lo; 885 } else if (Size == 64) { 886 // gcc passes <1 x double> in memory. :( 887 if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double)) 888 return; 889 890 // gcc passes <1 x long long> as INTEGER. 891 if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::LongLong)) 892 Current = Integer; 893 else 894 Current = SSE; 895 896 // If this type crosses an eightbyte boundary, it should be 897 // split. 898 if (OffsetBase && OffsetBase != 64) 899 Hi = Lo; 900 } else if (Size == 128) { 901 Lo = SSE; 902 Hi = SSEUp; 903 } 904 return; 905 } 906 907 if (const ComplexType *CT = Ty->getAs<ComplexType>()) { 908 QualType ET = getContext().getCanonicalType(CT->getElementType()); 909 910 uint64_t Size = getContext().getTypeSize(Ty); 911 if (ET->isIntegralOrEnumerationType()) { 912 if (Size <= 64) 913 Current = Integer; 914 else if (Size <= 128) 915 Lo = Hi = Integer; 916 } else if (ET == getContext().FloatTy) 917 Current = SSE; 918 else if (ET == getContext().DoubleTy) 919 Lo = Hi = SSE; 920 else if (ET == getContext().LongDoubleTy) 921 Current = ComplexX87; 922 923 // If this complex type crosses an eightbyte boundary then it 924 // should be split. 925 uint64_t EB_Real = (OffsetBase) / 64; 926 uint64_t EB_Imag = (OffsetBase + getContext().getTypeSize(ET)) / 64; 927 if (Hi == NoClass && EB_Real != EB_Imag) 928 Hi = Lo; 929 930 return; 931 } 932 933 if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) { 934 // Arrays are treated like structures. 935 936 uint64_t Size = getContext().getTypeSize(Ty); 937 938 // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger 939 // than two eightbytes, ..., it has class MEMORY. 940 if (Size > 128) 941 return; 942 943 // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned 944 // fields, it has class MEMORY. 945 // 946 // Only need to check alignment of array base. 947 if (OffsetBase % getContext().getTypeAlign(AT->getElementType())) 948 return; 949 950 // Otherwise implement simplified merge. We could be smarter about 951 // this, but it isn't worth it and would be harder to verify. 952 Current = NoClass; 953 uint64_t EltSize = getContext().getTypeSize(AT->getElementType()); 954 uint64_t ArraySize = AT->getSize().getZExtValue(); 955 for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) { 956 Class FieldLo, FieldHi; 957 classify(AT->getElementType(), Offset, FieldLo, FieldHi); 958 Lo = merge(Lo, FieldLo); 959 Hi = merge(Hi, FieldHi); 960 if (Lo == Memory || Hi == Memory) 961 break; 962 } 963 964 // Do post merger cleanup (see below). Only case we worry about is Memory. 965 if (Hi == Memory) 966 Lo = Memory; 967 assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification."); 968 return; 969 } 970 971 if (const RecordType *RT = Ty->getAs<RecordType>()) { 972 uint64_t Size = getContext().getTypeSize(Ty); 973 974 // AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger 975 // than two eightbytes, ..., it has class MEMORY. 976 if (Size > 128) 977 return; 978 979 // AMD64-ABI 3.2.3p2: Rule 2. If a C++ object has either a non-trivial 980 // copy constructor or a non-trivial destructor, it is passed by invisible 981 // reference. 982 if (hasNonTrivialDestructorOrCopyConstructor(RT)) 983 return; 984 985 const RecordDecl *RD = RT->getDecl(); 986 987 // Assume variable sized types are passed in memory. 988 if (RD->hasFlexibleArrayMember()) 989 return; 990 991 const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD); 992 993 // Reset Lo class, this will be recomputed. 994 Current = NoClass; 995 996 // If this is a C++ record, classify the bases first. 997 if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) { 998 for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(), 999 e = CXXRD->bases_end(); i != e; ++i) { 1000 assert(!i->isVirtual() && !i->getType()->isDependentType() && 1001 "Unexpected base class!"); 1002 const CXXRecordDecl *Base = 1003 cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl()); 1004 1005 // Classify this field. 1006 // 1007 // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate exceeds a 1008 // single eightbyte, each is classified separately. Each eightbyte gets 1009 // initialized to class NO_CLASS. 1010 Class FieldLo, FieldHi; 1011 uint64_t Offset = OffsetBase + Layout.getBaseClassOffset(Base); 1012 classify(i->getType(), Offset, FieldLo, FieldHi); 1013 Lo = merge(Lo, FieldLo); 1014 Hi = merge(Hi, FieldHi); 1015 if (Lo == Memory || Hi == Memory) 1016 break; 1017 } 1018 1019 // If this record has no fields, no bases, no vtable, but isn't empty, 1020 // classify as INTEGER. 1021 if (CXXRD->isEmpty() && Size) 1022 Current = Integer; 1023 } 1024 1025 // Classify the fields one at a time, merging the results. 1026 unsigned idx = 0; 1027 for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end(); 1028 i != e; ++i, ++idx) { 1029 uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx); 1030 bool BitField = i->isBitField(); 1031 1032 // AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned 1033 // fields, it has class MEMORY. 1034 // 1035 // Note, skip this test for bit-fields, see below. 1036 if (!BitField && Offset % getContext().getTypeAlign(i->getType())) { 1037 Lo = Memory; 1038 return; 1039 } 1040 1041 // Classify this field. 1042 // 1043 // AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate 1044 // exceeds a single eightbyte, each is classified 1045 // separately. Each eightbyte gets initialized to class 1046 // NO_CLASS. 1047 Class FieldLo, FieldHi; 1048 1049 // Bit-fields require special handling, they do not force the 1050 // structure to be passed in memory even if unaligned, and 1051 // therefore they can straddle an eightbyte. 1052 if (BitField) { 1053 // Ignore padding bit-fields. 1054 if (i->isUnnamedBitfield()) 1055 continue; 1056 1057 uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx); 1058 uint64_t Size = 1059 i->getBitWidth()->EvaluateAsInt(getContext()).getZExtValue(); 1060 1061 uint64_t EB_Lo = Offset / 64; 1062 uint64_t EB_Hi = (Offset + Size - 1) / 64; 1063 FieldLo = FieldHi = NoClass; 1064 if (EB_Lo) { 1065 assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes."); 1066 FieldLo = NoClass; 1067 FieldHi = Integer; 1068 } else { 1069 FieldLo = Integer; 1070 FieldHi = EB_Hi ? Integer : NoClass; 1071 } 1072 } else 1073 classify(i->getType(), Offset, FieldLo, FieldHi); 1074 Lo = merge(Lo, FieldLo); 1075 Hi = merge(Hi, FieldHi); 1076 if (Lo == Memory || Hi == Memory) 1077 break; 1078 } 1079 1080 // AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done: 1081 // 1082 // (a) If one of the classes is MEMORY, the whole argument is 1083 // passed in memory. 1084 // 1085 // (b) If SSEUP is not preceeded by SSE, it is converted to SSE. 1086 1087 // The first of these conditions is guaranteed by how we implement 1088 // the merge (just bail). 1089 // 1090 // The second condition occurs in the case of unions; for example 1091 // union { _Complex double; unsigned; }. 1092 if (Hi == Memory) 1093 Lo = Memory; 1094 if (Hi == SSEUp && Lo != SSE) 1095 Hi = SSE; 1096 } 1097} 1098 1099ABIArgInfo X86_64ABIInfo::getIndirectReturnResult(QualType Ty) const { 1100 // If this is a scalar LLVM value then assume LLVM will pass it in the right 1101 // place naturally. 1102 if (!CodeGenFunction::hasAggregateLLVMType(Ty)) { 1103 // Treat an enum type as its underlying type. 1104 if (const EnumType *EnumTy = Ty->getAs<EnumType>()) 1105 Ty = EnumTy->getDecl()->getIntegerType(); 1106 1107 return (Ty->isPromotableIntegerType() ? 1108 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 1109 } 1110 1111 return ABIArgInfo::getIndirect(0); 1112} 1113 1114ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty) const { 1115 // If this is a scalar LLVM value then assume LLVM will pass it in the right 1116 // place naturally. 1117 if (!CodeGenFunction::hasAggregateLLVMType(Ty)) { 1118 // Treat an enum type as its underlying type. 1119 if (const EnumType *EnumTy = Ty->getAs<EnumType>()) 1120 Ty = EnumTy->getDecl()->getIntegerType(); 1121 1122 return (Ty->isPromotableIntegerType() ? 1123 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 1124 } 1125 1126 if (isRecordWithNonTrivialDestructorOrCopyConstructor(Ty)) 1127 return ABIArgInfo::getIndirect(0, /*ByVal=*/false); 1128 1129 // Compute the byval alignment. We trust the back-end to honor the 1130 // minimum ABI alignment for byval, to make cleaner IR. 1131 const unsigned MinABIAlign = 8; 1132 unsigned Align = getContext().getTypeAlign(Ty) / 8; 1133 if (Align > MinABIAlign) 1134 return ABIArgInfo::getIndirect(Align); 1135 return ABIArgInfo::getIndirect(0); 1136} 1137 1138/// Get16ByteVectorType - The ABI specifies that a value should be passed in an 1139/// full vector XMM register. Pick an LLVM IR type that will be passed as a 1140/// vector register. 1141const llvm::Type *X86_64ABIInfo::Get16ByteVectorType(QualType Ty) const { 1142 const llvm::Type *IRType = CGT.ConvertTypeRecursive(Ty); 1143 1144 // Wrapper structs that just contain vectors are passed just like vectors, 1145 // strip them off if present. 1146 const llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType); 1147 while (STy && STy->getNumElements() == 1) { 1148 IRType = STy->getElementType(0); 1149 STy = dyn_cast<llvm::StructType>(IRType); 1150 } 1151 1152 // If the preferred type is a 16-byte vector, prefer to pass it. 1153 if (const llvm::VectorType *VT = dyn_cast<llvm::VectorType>(IRType)){ 1154 const llvm::Type *EltTy = VT->getElementType(); 1155 if (VT->getBitWidth() == 128 && 1156 (EltTy->isFloatTy() || EltTy->isDoubleTy() || 1157 EltTy->isIntegerTy(8) || EltTy->isIntegerTy(16) || 1158 EltTy->isIntegerTy(32) || EltTy->isIntegerTy(64) || 1159 EltTy->isIntegerTy(128))) 1160 return VT; 1161 } 1162 1163 return llvm::VectorType::get(llvm::Type::getDoubleTy(getVMContext()), 2); 1164} 1165 1166/// BitsContainNoUserData - Return true if the specified [start,end) bit range 1167/// is known to either be off the end of the specified type or being in 1168/// alignment padding. The user type specified is known to be at most 128 bits 1169/// in size, and have passed through X86_64ABIInfo::classify with a successful 1170/// classification that put one of the two halves in the INTEGER class. 1171/// 1172/// It is conservatively correct to return false. 1173static bool BitsContainNoUserData(QualType Ty, unsigned StartBit, 1174 unsigned EndBit, ASTContext &Context) { 1175 // If the bytes being queried are off the end of the type, there is no user 1176 // data hiding here. This handles analysis of builtins, vectors and other 1177 // types that don't contain interesting padding. 1178 unsigned TySize = (unsigned)Context.getTypeSize(Ty); 1179 if (TySize <= StartBit) 1180 return true; 1181 1182 if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) { 1183 unsigned EltSize = (unsigned)Context.getTypeSize(AT->getElementType()); 1184 unsigned NumElts = (unsigned)AT->getSize().getZExtValue(); 1185 1186 // Check each element to see if the element overlaps with the queried range. 1187 for (unsigned i = 0; i != NumElts; ++i) { 1188 // If the element is after the span we care about, then we're done.. 1189 unsigned EltOffset = i*EltSize; 1190 if (EltOffset >= EndBit) break; 1191 1192 unsigned EltStart = EltOffset < StartBit ? StartBit-EltOffset :0; 1193 if (!BitsContainNoUserData(AT->getElementType(), EltStart, 1194 EndBit-EltOffset, Context)) 1195 return false; 1196 } 1197 // If it overlaps no elements, then it is safe to process as padding. 1198 return true; 1199 } 1200 1201 if (const RecordType *RT = Ty->getAs<RecordType>()) { 1202 const RecordDecl *RD = RT->getDecl(); 1203 const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD); 1204 1205 // If this is a C++ record, check the bases first. 1206 if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) { 1207 for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(), 1208 e = CXXRD->bases_end(); i != e; ++i) { 1209 assert(!i->isVirtual() && !i->getType()->isDependentType() && 1210 "Unexpected base class!"); 1211 const CXXRecordDecl *Base = 1212 cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl()); 1213 1214 // If the base is after the span we care about, ignore it. 1215 unsigned BaseOffset = (unsigned)Layout.getBaseClassOffset(Base); 1216 if (BaseOffset >= EndBit) continue; 1217 1218 unsigned BaseStart = BaseOffset < StartBit ? StartBit-BaseOffset :0; 1219 if (!BitsContainNoUserData(i->getType(), BaseStart, 1220 EndBit-BaseOffset, Context)) 1221 return false; 1222 } 1223 } 1224 1225 // Verify that no field has data that overlaps the region of interest. Yes 1226 // this could be sped up a lot by being smarter about queried fields, 1227 // however we're only looking at structs up to 16 bytes, so we don't care 1228 // much. 1229 unsigned idx = 0; 1230 for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end(); 1231 i != e; ++i, ++idx) { 1232 unsigned FieldOffset = (unsigned)Layout.getFieldOffset(idx); 1233 1234 // If we found a field after the region we care about, then we're done. 1235 if (FieldOffset >= EndBit) break; 1236 1237 unsigned FieldStart = FieldOffset < StartBit ? StartBit-FieldOffset :0; 1238 if (!BitsContainNoUserData(i->getType(), FieldStart, EndBit-FieldOffset, 1239 Context)) 1240 return false; 1241 } 1242 1243 // If nothing in this record overlapped the area of interest, then we're 1244 // clean. 1245 return true; 1246 } 1247 1248 return false; 1249} 1250 1251/// ContainsFloatAtOffset - Return true if the specified LLVM IR type has a 1252/// float member at the specified offset. For example, {int,{float}} has a 1253/// float at offset 4. It is conservatively correct for this routine to return 1254/// false. 1255static bool ContainsFloatAtOffset(const llvm::Type *IRType, unsigned IROffset, 1256 const llvm::TargetData &TD) { 1257 // Base case if we find a float. 1258 if (IROffset == 0 && IRType->isFloatTy()) 1259 return true; 1260 1261 // If this is a struct, recurse into the field at the specified offset. 1262 if (const llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) { 1263 const llvm::StructLayout *SL = TD.getStructLayout(STy); 1264 unsigned Elt = SL->getElementContainingOffset(IROffset); 1265 IROffset -= SL->getElementOffset(Elt); 1266 return ContainsFloatAtOffset(STy->getElementType(Elt), IROffset, TD); 1267 } 1268 1269 // If this is an array, recurse into the field at the specified offset. 1270 if (const llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) { 1271 const llvm::Type *EltTy = ATy->getElementType(); 1272 unsigned EltSize = TD.getTypeAllocSize(EltTy); 1273 IROffset -= IROffset/EltSize*EltSize; 1274 return ContainsFloatAtOffset(EltTy, IROffset, TD); 1275 } 1276 1277 return false; 1278} 1279 1280 1281/// GetSSETypeAtOffset - Return a type that will be passed by the backend in the 1282/// low 8 bytes of an XMM register, corresponding to the SSE class. 1283const llvm::Type *X86_64ABIInfo:: 1284GetSSETypeAtOffset(const llvm::Type *IRType, unsigned IROffset, 1285 QualType SourceTy, unsigned SourceOffset) const { 1286 // The only three choices we have are either double, <2 x float>, or float. We 1287 // pass as float if the last 4 bytes is just padding. This happens for 1288 // structs that contain 3 floats. 1289 if (BitsContainNoUserData(SourceTy, SourceOffset*8+32, 1290 SourceOffset*8+64, getContext())) 1291 return llvm::Type::getFloatTy(getVMContext()); 1292 1293 // We want to pass as <2 x float> if the LLVM IR type contains a float at 1294 // offset+0 and offset+4. Walk the LLVM IR type to find out if this is the 1295 // case. 1296 if (ContainsFloatAtOffset(IRType, IROffset, getTargetData()) && 1297 ContainsFloatAtOffset(IRType, IROffset+4, getTargetData())) { 1298 // FIXME: <2 x float> doesn't pass as one XMM register yet. Don't enable 1299 // this code until it does. 1300 //return llvm::VectorType::get(llvm::Type::getFloatTy(getVMContext()), 2); 1301 1302 } 1303 1304 return llvm::Type::getDoubleTy(getVMContext()); 1305} 1306 1307 1308/// GetINTEGERTypeAtOffset - The ABI specifies that a value should be passed in 1309/// an 8-byte GPR. This means that we either have a scalar or we are talking 1310/// about the high or low part of an up-to-16-byte struct. This routine picks 1311/// the best LLVM IR type to represent this, which may be i64 or may be anything 1312/// else that the backend will pass in a GPR that works better (e.g. i8, %foo*, 1313/// etc). 1314/// 1315/// PrefType is an LLVM IR type that corresponds to (part of) the IR type for 1316/// the source type. IROffset is an offset in bytes into the LLVM IR type that 1317/// the 8-byte value references. PrefType may be null. 1318/// 1319/// SourceTy is the source level type for the entire argument. SourceOffset is 1320/// an offset into this that we're processing (which is always either 0 or 8). 1321/// 1322const llvm::Type *X86_64ABIInfo:: 1323GetINTEGERTypeAtOffset(const llvm::Type *IRType, unsigned IROffset, 1324 QualType SourceTy, unsigned SourceOffset) const { 1325 // If we're dealing with an un-offset LLVM IR type, then it means that we're 1326 // returning an 8-byte unit starting with it. See if we can safely use it. 1327 if (IROffset == 0) { 1328 // Pointers and int64's always fill the 8-byte unit. 1329 if (isa<llvm::PointerType>(IRType) || IRType->isIntegerTy(64)) 1330 return IRType; 1331 1332 // If we have a 1/2/4-byte integer, we can use it only if the rest of the 1333 // goodness in the source type is just tail padding. This is allowed to 1334 // kick in for struct {double,int} on the int, but not on 1335 // struct{double,int,int} because we wouldn't return the second int. We 1336 // have to do this analysis on the source type because we can't depend on 1337 // unions being lowered a specific way etc. 1338 if (IRType->isIntegerTy(8) || IRType->isIntegerTy(16) || 1339 IRType->isIntegerTy(32)) { 1340 unsigned BitWidth = cast<llvm::IntegerType>(IRType)->getBitWidth(); 1341 1342 if (BitsContainNoUserData(SourceTy, SourceOffset*8+BitWidth, 1343 SourceOffset*8+64, getContext())) 1344 return IRType; 1345 } 1346 } 1347 1348 if (const llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) { 1349 // If this is a struct, recurse into the field at the specified offset. 1350 const llvm::StructLayout *SL = getTargetData().getStructLayout(STy); 1351 if (IROffset < SL->getSizeInBytes()) { 1352 unsigned FieldIdx = SL->getElementContainingOffset(IROffset); 1353 IROffset -= SL->getElementOffset(FieldIdx); 1354 1355 return GetINTEGERTypeAtOffset(STy->getElementType(FieldIdx), IROffset, 1356 SourceTy, SourceOffset); 1357 } 1358 } 1359 1360 if (const llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) { 1361 const llvm::Type *EltTy = ATy->getElementType(); 1362 unsigned EltSize = getTargetData().getTypeAllocSize(EltTy); 1363 unsigned EltOffset = IROffset/EltSize*EltSize; 1364 return GetINTEGERTypeAtOffset(EltTy, IROffset-EltOffset, SourceTy, 1365 SourceOffset); 1366 } 1367 1368 // Okay, we don't have any better idea of what to pass, so we pass this in an 1369 // integer register that isn't too big to fit the rest of the struct. 1370 unsigned TySizeInBytes = 1371 (unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity(); 1372 1373 assert(TySizeInBytes != SourceOffset && "Empty field?"); 1374 1375 // It is always safe to classify this as an integer type up to i64 that 1376 // isn't larger than the structure. 1377 return llvm::IntegerType::get(getVMContext(), 1378 std::min(TySizeInBytes-SourceOffset, 8U)*8); 1379} 1380 1381ABIArgInfo X86_64ABIInfo:: 1382classifyReturnType(QualType RetTy) const { 1383 // AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the 1384 // classification algorithm. 1385 X86_64ABIInfo::Class Lo, Hi; 1386 classify(RetTy, 0, Lo, Hi); 1387 1388 // Check some invariants. 1389 assert((Hi != Memory || Lo == Memory) && "Invalid memory classification."); 1390 assert((Lo != NoClass || Hi == NoClass) && "Invalid null classification."); 1391 assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification."); 1392 1393 const llvm::Type *ResType = 0; 1394 switch (Lo) { 1395 case NoClass: 1396 return ABIArgInfo::getIgnore(); 1397 1398 case SSEUp: 1399 case X87Up: 1400 assert(0 && "Invalid classification for lo word."); 1401 1402 // AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via 1403 // hidden argument. 1404 case Memory: 1405 return getIndirectReturnResult(RetTy); 1406 1407 // AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next 1408 // available register of the sequence %rax, %rdx is used. 1409 case Integer: 1410 ResType = GetINTEGERTypeAtOffset(CGT.ConvertTypeRecursive(RetTy), 0, 1411 RetTy, 0); 1412 1413 // If we have a sign or zero extended integer, make sure to return Extend 1414 // so that the parameter gets the right LLVM IR attributes. 1415 if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) { 1416 // Treat an enum type as its underlying type. 1417 if (const EnumType *EnumTy = RetTy->getAs<EnumType>()) 1418 RetTy = EnumTy->getDecl()->getIntegerType(); 1419 1420 if (RetTy->isIntegralOrEnumerationType() && 1421 RetTy->isPromotableIntegerType()) 1422 return ABIArgInfo::getExtend(); 1423 } 1424 break; 1425 1426 // AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next 1427 // available SSE register of the sequence %xmm0, %xmm1 is used. 1428 case SSE: 1429 ResType = GetSSETypeAtOffset(CGT.ConvertTypeRecursive(RetTy), 0, RetTy, 0); 1430 break; 1431 1432 // AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is 1433 // returned on the X87 stack in %st0 as 80-bit x87 number. 1434 case X87: 1435 ResType = llvm::Type::getX86_FP80Ty(getVMContext()); 1436 break; 1437 1438 // AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real 1439 // part of the value is returned in %st0 and the imaginary part in 1440 // %st1. 1441 case ComplexX87: 1442 assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification."); 1443 ResType = llvm::StructType::get(getVMContext(), 1444 llvm::Type::getX86_FP80Ty(getVMContext()), 1445 llvm::Type::getX86_FP80Ty(getVMContext()), 1446 NULL); 1447 break; 1448 } 1449 1450 switch (Hi) { 1451 // Memory was handled previously and X87 should 1452 // never occur as a hi class. 1453 case Memory: 1454 case X87: 1455 assert(0 && "Invalid classification for hi word."); 1456 1457 case ComplexX87: // Previously handled. 1458 case NoClass: 1459 break; 1460 1461 case Integer: { 1462 const llvm::Type *HiType = 1463 GetINTEGERTypeAtOffset(CGT.ConvertTypeRecursive(RetTy), 8, RetTy, 8); 1464 ResType = llvm::StructType::get(getVMContext(), ResType, HiType, NULL); 1465 break; 1466 } 1467 case SSE: { 1468 const llvm::Type *HiType = 1469 GetSSETypeAtOffset(CGT.ConvertTypeRecursive(RetTy), 8, RetTy, 8); 1470 ResType = llvm::StructType::get(getVMContext(), ResType, HiType,NULL); 1471 break; 1472 } 1473 1474 // AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte 1475 // is passed in the upper half of the last used SSE register. 1476 // 1477 // SSEUP should always be preceeded by SSE, just widen. 1478 case SSEUp: 1479 assert(Lo == SSE && "Unexpected SSEUp classification."); 1480 ResType = Get16ByteVectorType(RetTy); 1481 break; 1482 1483 // AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is 1484 // returned together with the previous X87 value in %st0. 1485 case X87Up: 1486 // If X87Up is preceeded by X87, we don't need to do 1487 // anything. However, in some cases with unions it may not be 1488 // preceeded by X87. In such situations we follow gcc and pass the 1489 // extra bits in an SSE reg. 1490 if (Lo != X87) { 1491 const llvm::Type *HiType = 1492 GetSSETypeAtOffset(CGT.ConvertTypeRecursive(RetTy), 8, RetTy, 8); 1493 ResType = llvm::StructType::get(getVMContext(), ResType, HiType, NULL); 1494 } 1495 break; 1496 } 1497 1498 return ABIArgInfo::getDirect(ResType); 1499} 1500 1501ABIArgInfo X86_64ABIInfo::classifyArgumentType(QualType Ty, unsigned &neededInt, 1502 unsigned &neededSSE) const { 1503 X86_64ABIInfo::Class Lo, Hi; 1504 classify(Ty, 0, Lo, Hi); 1505 1506 // Check some invariants. 1507 // FIXME: Enforce these by construction. 1508 assert((Hi != Memory || Lo == Memory) && "Invalid memory classification."); 1509 assert((Lo != NoClass || Hi == NoClass) && "Invalid null classification."); 1510 assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification."); 1511 1512 neededInt = 0; 1513 neededSSE = 0; 1514 const llvm::Type *ResType = 0; 1515 switch (Lo) { 1516 case NoClass: 1517 return ABIArgInfo::getIgnore(); 1518 1519 // AMD64-ABI 3.2.3p3: Rule 1. If the class is MEMORY, pass the argument 1520 // on the stack. 1521 case Memory: 1522 1523 // AMD64-ABI 3.2.3p3: Rule 5. If the class is X87, X87UP or 1524 // COMPLEX_X87, it is passed in memory. 1525 case X87: 1526 case ComplexX87: 1527 return getIndirectResult(Ty); 1528 1529 case SSEUp: 1530 case X87Up: 1531 assert(0 && "Invalid classification for lo word."); 1532 1533 // AMD64-ABI 3.2.3p3: Rule 2. If the class is INTEGER, the next 1534 // available register of the sequence %rdi, %rsi, %rdx, %rcx, %r8 1535 // and %r9 is used. 1536 case Integer: 1537 ++neededInt; 1538 1539 // Pick an 8-byte type based on the preferred type. 1540 ResType = GetINTEGERTypeAtOffset(CGT.ConvertTypeRecursive(Ty), 0, Ty, 0); 1541 1542 // If we have a sign or zero extended integer, make sure to return Extend 1543 // so that the parameter gets the right LLVM IR attributes. 1544 if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) { 1545 // Treat an enum type as its underlying type. 1546 if (const EnumType *EnumTy = Ty->getAs<EnumType>()) 1547 Ty = EnumTy->getDecl()->getIntegerType(); 1548 1549 if (Ty->isIntegralOrEnumerationType() && 1550 Ty->isPromotableIntegerType()) 1551 return ABIArgInfo::getExtend(); 1552 } 1553 1554 break; 1555 1556 // AMD64-ABI 3.2.3p3: Rule 3. If the class is SSE, the next 1557 // available SSE register is used, the registers are taken in the 1558 // order from %xmm0 to %xmm7. 1559 case SSE: 1560 ++neededSSE; 1561 ResType = GetSSETypeAtOffset(CGT.ConvertTypeRecursive(Ty), 0, Ty, 0); 1562 break; 1563 } 1564 1565 switch (Hi) { 1566 // Memory was handled previously, ComplexX87 and X87 should 1567 // never occur as hi classes, and X87Up must be preceed by X87, 1568 // which is passed in memory. 1569 case Memory: 1570 case X87: 1571 case ComplexX87: 1572 assert(0 && "Invalid classification for hi word."); 1573 break; 1574 1575 case NoClass: break; 1576 1577 case Integer: { 1578 ++neededInt; 1579 // Pick an 8-byte type based on the preferred type. 1580 const llvm::Type *HiType = 1581 GetINTEGERTypeAtOffset(CGT.ConvertTypeRecursive(Ty), 8, Ty, 8); 1582 ResType = llvm::StructType::get(getVMContext(), ResType, HiType, NULL); 1583 break; 1584 } 1585 1586 // X87Up generally doesn't occur here (long double is passed in 1587 // memory), except in situations involving unions. 1588 case X87Up: 1589 case SSE: { 1590 const llvm::Type *HiType = 1591 GetSSETypeAtOffset(CGT.ConvertTypeRecursive(Ty), 8, Ty, 8); 1592 ResType = llvm::StructType::get(getVMContext(), ResType, HiType, NULL); 1593 ++neededSSE; 1594 break; 1595 } 1596 1597 // AMD64-ABI 3.2.3p3: Rule 4. If the class is SSEUP, the 1598 // eightbyte is passed in the upper half of the last used SSE 1599 // register. This only happens when 128-bit vectors are passed. 1600 case SSEUp: 1601 assert(Lo == SSE && "Unexpected SSEUp classification"); 1602 ResType = Get16ByteVectorType(Ty); 1603 break; 1604 } 1605 1606 return ABIArgInfo::getDirect(ResType); 1607} 1608 1609void X86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const { 1610 1611 FI.getReturnInfo() = classifyReturnType(FI.getReturnType()); 1612 1613 // Keep track of the number of assigned registers. 1614 unsigned freeIntRegs = 6, freeSSERegs = 8; 1615 1616 // If the return value is indirect, then the hidden argument is consuming one 1617 // integer register. 1618 if (FI.getReturnInfo().isIndirect()) 1619 --freeIntRegs; 1620 1621 // AMD64-ABI 3.2.3p3: Once arguments are classified, the registers 1622 // get assigned (in left-to-right order) for passing as follows... 1623 for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end(); 1624 it != ie; ++it) { 1625 unsigned neededInt, neededSSE; 1626 it->info = classifyArgumentType(it->type, neededInt, neededSSE); 1627 1628 // AMD64-ABI 3.2.3p3: If there are no registers available for any 1629 // eightbyte of an argument, the whole argument is passed on the 1630 // stack. If registers have already been assigned for some 1631 // eightbytes of such an argument, the assignments get reverted. 1632 if (freeIntRegs >= neededInt && freeSSERegs >= neededSSE) { 1633 freeIntRegs -= neededInt; 1634 freeSSERegs -= neededSSE; 1635 } else { 1636 it->info = getIndirectResult(it->type); 1637 } 1638 } 1639} 1640 1641static llvm::Value *EmitVAArgFromMemory(llvm::Value *VAListAddr, 1642 QualType Ty, 1643 CodeGenFunction &CGF) { 1644 llvm::Value *overflow_arg_area_p = 1645 CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_p"); 1646 llvm::Value *overflow_arg_area = 1647 CGF.Builder.CreateLoad(overflow_arg_area_p, "overflow_arg_area"); 1648 1649 // AMD64-ABI 3.5.7p5: Step 7. Align l->overflow_arg_area upwards to a 16 1650 // byte boundary if alignment needed by type exceeds 8 byte boundary. 1651 uint64_t Align = CGF.getContext().getTypeAlign(Ty) / 8; 1652 if (Align > 8) { 1653 // Note that we follow the ABI & gcc here, even though the type 1654 // could in theory have an alignment greater than 16. This case 1655 // shouldn't ever matter in practice. 1656 1657 // overflow_arg_area = (overflow_arg_area + 15) & ~15; 1658 llvm::Value *Offset = 1659 llvm::ConstantInt::get(CGF.Int32Ty, 15); 1660 overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset); 1661 llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(overflow_arg_area, 1662 CGF.Int64Ty); 1663 llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int64Ty, ~15LL); 1664 overflow_arg_area = 1665 CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask), 1666 overflow_arg_area->getType(), 1667 "overflow_arg_area.align"); 1668 } 1669 1670 // AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area. 1671 const llvm::Type *LTy = CGF.ConvertTypeForMem(Ty); 1672 llvm::Value *Res = 1673 CGF.Builder.CreateBitCast(overflow_arg_area, 1674 llvm::PointerType::getUnqual(LTy)); 1675 1676 // AMD64-ABI 3.5.7p5: Step 9. Set l->overflow_arg_area to: 1677 // l->overflow_arg_area + sizeof(type). 1678 // AMD64-ABI 3.5.7p5: Step 10. Align l->overflow_arg_area upwards to 1679 // an 8 byte boundary. 1680 1681 uint64_t SizeInBytes = (CGF.getContext().getTypeSize(Ty) + 7) / 8; 1682 llvm::Value *Offset = 1683 llvm::ConstantInt::get(CGF.Int32Ty, (SizeInBytes + 7) & ~7); 1684 overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset, 1685 "overflow_arg_area.next"); 1686 CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p); 1687 1688 // AMD64-ABI 3.5.7p5: Step 11. Return the fetched type. 1689 return Res; 1690} 1691 1692llvm::Value *X86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 1693 CodeGenFunction &CGF) const { 1694 llvm::LLVMContext &VMContext = CGF.getLLVMContext(); 1695 1696 // Assume that va_list type is correct; should be pointer to LLVM type: 1697 // struct { 1698 // i32 gp_offset; 1699 // i32 fp_offset; 1700 // i8* overflow_arg_area; 1701 // i8* reg_save_area; 1702 // }; 1703 unsigned neededInt, neededSSE; 1704 1705 Ty = CGF.getContext().getCanonicalType(Ty); 1706 ABIArgInfo AI = classifyArgumentType(Ty, neededInt, neededSSE); 1707 1708 // AMD64-ABI 3.5.7p5: Step 1. Determine whether type may be passed 1709 // in the registers. If not go to step 7. 1710 if (!neededInt && !neededSSE) 1711 return EmitVAArgFromMemory(VAListAddr, Ty, CGF); 1712 1713 // AMD64-ABI 3.5.7p5: Step 2. Compute num_gp to hold the number of 1714 // general purpose registers needed to pass type and num_fp to hold 1715 // the number of floating point registers needed. 1716 1717 // AMD64-ABI 3.5.7p5: Step 3. Verify whether arguments fit into 1718 // registers. In the case: l->gp_offset > 48 - num_gp * 8 or 1719 // l->fp_offset > 304 - num_fp * 16 go to step 7. 1720 // 1721 // NOTE: 304 is a typo, there are (6 * 8 + 8 * 16) = 176 bytes of 1722 // register save space). 1723 1724 llvm::Value *InRegs = 0; 1725 llvm::Value *gp_offset_p = 0, *gp_offset = 0; 1726 llvm::Value *fp_offset_p = 0, *fp_offset = 0; 1727 if (neededInt) { 1728 gp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "gp_offset_p"); 1729 gp_offset = CGF.Builder.CreateLoad(gp_offset_p, "gp_offset"); 1730 InRegs = llvm::ConstantInt::get(CGF.Int32Ty, 48 - neededInt * 8); 1731 InRegs = CGF.Builder.CreateICmpULE(gp_offset, InRegs, "fits_in_gp"); 1732 } 1733 1734 if (neededSSE) { 1735 fp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 1, "fp_offset_p"); 1736 fp_offset = CGF.Builder.CreateLoad(fp_offset_p, "fp_offset"); 1737 llvm::Value *FitsInFP = 1738 llvm::ConstantInt::get(CGF.Int32Ty, 176 - neededSSE * 16); 1739 FitsInFP = CGF.Builder.CreateICmpULE(fp_offset, FitsInFP, "fits_in_fp"); 1740 InRegs = InRegs ? CGF.Builder.CreateAnd(InRegs, FitsInFP) : FitsInFP; 1741 } 1742 1743 llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg"); 1744 llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem"); 1745 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end"); 1746 CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock); 1747 1748 // Emit code to load the value if it was passed in registers. 1749 1750 CGF.EmitBlock(InRegBlock); 1751 1752 // AMD64-ABI 3.5.7p5: Step 4. Fetch type from l->reg_save_area with 1753 // an offset of l->gp_offset and/or l->fp_offset. This may require 1754 // copying to a temporary location in case the parameter is passed 1755 // in different register classes or requires an alignment greater 1756 // than 8 for general purpose registers and 16 for XMM registers. 1757 // 1758 // FIXME: This really results in shameful code when we end up needing to 1759 // collect arguments from different places; often what should result in a 1760 // simple assembling of a structure from scattered addresses has many more 1761 // loads than necessary. Can we clean this up? 1762 const llvm::Type *LTy = CGF.ConvertTypeForMem(Ty); 1763 llvm::Value *RegAddr = 1764 CGF.Builder.CreateLoad(CGF.Builder.CreateStructGEP(VAListAddr, 3), 1765 "reg_save_area"); 1766 if (neededInt && neededSSE) { 1767 // FIXME: Cleanup. 1768 assert(AI.isDirect() && "Unexpected ABI info for mixed regs"); 1769 const llvm::StructType *ST = cast<llvm::StructType>(AI.getCoerceToType()); 1770 llvm::Value *Tmp = CGF.CreateTempAlloca(ST); 1771 assert(ST->getNumElements() == 2 && "Unexpected ABI info for mixed regs"); 1772 const llvm::Type *TyLo = ST->getElementType(0); 1773 const llvm::Type *TyHi = ST->getElementType(1); 1774 assert((TyLo->isFloatingPointTy() ^ TyHi->isFloatingPointTy()) && 1775 "Unexpected ABI info for mixed regs"); 1776 const llvm::Type *PTyLo = llvm::PointerType::getUnqual(TyLo); 1777 const llvm::Type *PTyHi = llvm::PointerType::getUnqual(TyHi); 1778 llvm::Value *GPAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset); 1779 llvm::Value *FPAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset); 1780 llvm::Value *RegLoAddr = TyLo->isFloatingPointTy() ? FPAddr : GPAddr; 1781 llvm::Value *RegHiAddr = TyLo->isFloatingPointTy() ? GPAddr : FPAddr; 1782 llvm::Value *V = 1783 CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegLoAddr, PTyLo)); 1784 CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0)); 1785 V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegHiAddr, PTyHi)); 1786 CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1)); 1787 1788 RegAddr = CGF.Builder.CreateBitCast(Tmp, 1789 llvm::PointerType::getUnqual(LTy)); 1790 } else if (neededInt) { 1791 RegAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset); 1792 RegAddr = CGF.Builder.CreateBitCast(RegAddr, 1793 llvm::PointerType::getUnqual(LTy)); 1794 } else if (neededSSE == 1) { 1795 RegAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset); 1796 RegAddr = CGF.Builder.CreateBitCast(RegAddr, 1797 llvm::PointerType::getUnqual(LTy)); 1798 } else { 1799 assert(neededSSE == 2 && "Invalid number of needed registers!"); 1800 // SSE registers are spaced 16 bytes apart in the register save 1801 // area, we need to collect the two eightbytes together. 1802 llvm::Value *RegAddrLo = CGF.Builder.CreateGEP(RegAddr, fp_offset); 1803 llvm::Value *RegAddrHi = CGF.Builder.CreateConstGEP1_32(RegAddrLo, 16); 1804 const llvm::Type *DoubleTy = llvm::Type::getDoubleTy(VMContext); 1805 const llvm::Type *DblPtrTy = 1806 llvm::PointerType::getUnqual(DoubleTy); 1807 const llvm::StructType *ST = llvm::StructType::get(VMContext, DoubleTy, 1808 DoubleTy, NULL); 1809 llvm::Value *V, *Tmp = CGF.CreateTempAlloca(ST); 1810 V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrLo, 1811 DblPtrTy)); 1812 CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0)); 1813 V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrHi, 1814 DblPtrTy)); 1815 CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1)); 1816 RegAddr = CGF.Builder.CreateBitCast(Tmp, 1817 llvm::PointerType::getUnqual(LTy)); 1818 } 1819 1820 // AMD64-ABI 3.5.7p5: Step 5. Set: 1821 // l->gp_offset = l->gp_offset + num_gp * 8 1822 // l->fp_offset = l->fp_offset + num_fp * 16. 1823 if (neededInt) { 1824 llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededInt * 8); 1825 CGF.Builder.CreateStore(CGF.Builder.CreateAdd(gp_offset, Offset), 1826 gp_offset_p); 1827 } 1828 if (neededSSE) { 1829 llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededSSE * 16); 1830 CGF.Builder.CreateStore(CGF.Builder.CreateAdd(fp_offset, Offset), 1831 fp_offset_p); 1832 } 1833 CGF.EmitBranch(ContBlock); 1834 1835 // Emit code to load the value if it was passed in memory. 1836 1837 CGF.EmitBlock(InMemBlock); 1838 llvm::Value *MemAddr = EmitVAArgFromMemory(VAListAddr, Ty, CGF); 1839 1840 // Return the appropriate result. 1841 1842 CGF.EmitBlock(ContBlock); 1843 llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(RegAddr->getType(), 1844 "vaarg.addr"); 1845 ResAddr->reserveOperandSpace(2); 1846 ResAddr->addIncoming(RegAddr, InRegBlock); 1847 ResAddr->addIncoming(MemAddr, InMemBlock); 1848 return ResAddr; 1849} 1850 1851 1852 1853//===----------------------------------------------------------------------===// 1854// PIC16 ABI Implementation 1855//===----------------------------------------------------------------------===// 1856 1857namespace { 1858 1859class PIC16ABIInfo : public ABIInfo { 1860public: 1861 PIC16ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {} 1862 1863 ABIArgInfo classifyReturnType(QualType RetTy) const; 1864 1865 ABIArgInfo classifyArgumentType(QualType RetTy) const; 1866 1867 virtual void computeInfo(CGFunctionInfo &FI) const { 1868 FI.getReturnInfo() = classifyReturnType(FI.getReturnType()); 1869 for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end(); 1870 it != ie; ++it) 1871 it->info = classifyArgumentType(it->type); 1872 } 1873 1874 virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 1875 CodeGenFunction &CGF) const; 1876}; 1877 1878class PIC16TargetCodeGenInfo : public TargetCodeGenInfo { 1879public: 1880 PIC16TargetCodeGenInfo(CodeGenTypes &CGT) 1881 : TargetCodeGenInfo(new PIC16ABIInfo(CGT)) {} 1882}; 1883 1884} 1885 1886ABIArgInfo PIC16ABIInfo::classifyReturnType(QualType RetTy) const { 1887 if (RetTy->isVoidType()) { 1888 return ABIArgInfo::getIgnore(); 1889 } else { 1890 return ABIArgInfo::getDirect(); 1891 } 1892} 1893 1894ABIArgInfo PIC16ABIInfo::classifyArgumentType(QualType Ty) const { 1895 return ABIArgInfo::getDirect(); 1896} 1897 1898llvm::Value *PIC16ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 1899 CodeGenFunction &CGF) const { 1900 const llvm::Type *BP = llvm::Type::getInt8PtrTy(CGF.getLLVMContext()); 1901 const llvm::Type *BPP = llvm::PointerType::getUnqual(BP); 1902 1903 CGBuilderTy &Builder = CGF.Builder; 1904 llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, 1905 "ap"); 1906 llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur"); 1907 llvm::Type *PTy = 1908 llvm::PointerType::getUnqual(CGF.ConvertType(Ty)); 1909 llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy); 1910 1911 uint64_t Offset = CGF.getContext().getTypeSize(Ty) / 8; 1912 1913 llvm::Value *NextAddr = 1914 Builder.CreateGEP(Addr, llvm::ConstantInt::get( 1915 llvm::Type::getInt32Ty(CGF.getLLVMContext()), Offset), 1916 "ap.next"); 1917 Builder.CreateStore(NextAddr, VAListAddrAsBPP); 1918 1919 return AddrTyped; 1920} 1921 1922 1923// PowerPC-32 1924 1925namespace { 1926class PPC32TargetCodeGenInfo : public DefaultTargetCodeGenInfo { 1927public: 1928 PPC32TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {} 1929 1930 int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const { 1931 // This is recovered from gcc output. 1932 return 1; // r1 is the dedicated stack pointer 1933 } 1934 1935 bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF, 1936 llvm::Value *Address) const; 1937}; 1938 1939} 1940 1941bool 1942PPC32TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF, 1943 llvm::Value *Address) const { 1944 // This is calculated from the LLVM and GCC tables and verified 1945 // against gcc output. AFAIK all ABIs use the same encoding. 1946 1947 CodeGen::CGBuilderTy &Builder = CGF.Builder; 1948 llvm::LLVMContext &Context = CGF.getLLVMContext(); 1949 1950 const llvm::IntegerType *i8 = llvm::Type::getInt8Ty(Context); 1951 llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4); 1952 llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8); 1953 llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16); 1954 1955 // 0-31: r0-31, the 4-byte general-purpose registers 1956 AssignToArrayRange(Builder, Address, Four8, 0, 31); 1957 1958 // 32-63: fp0-31, the 8-byte floating-point registers 1959 AssignToArrayRange(Builder, Address, Eight8, 32, 63); 1960 1961 // 64-76 are various 4-byte special-purpose registers: 1962 // 64: mq 1963 // 65: lr 1964 // 66: ctr 1965 // 67: ap 1966 // 68-75 cr0-7 1967 // 76: xer 1968 AssignToArrayRange(Builder, Address, Four8, 64, 76); 1969 1970 // 77-108: v0-31, the 16-byte vector registers 1971 AssignToArrayRange(Builder, Address, Sixteen8, 77, 108); 1972 1973 // 109: vrsave 1974 // 110: vscr 1975 // 111: spe_acc 1976 // 112: spefscr 1977 // 113: sfp 1978 AssignToArrayRange(Builder, Address, Four8, 109, 113); 1979 1980 return false; 1981} 1982 1983 1984//===----------------------------------------------------------------------===// 1985// ARM ABI Implementation 1986//===----------------------------------------------------------------------===// 1987 1988namespace { 1989 1990class ARMABIInfo : public ABIInfo { 1991public: 1992 enum ABIKind { 1993 APCS = 0, 1994 AAPCS = 1, 1995 AAPCS_VFP 1996 }; 1997 1998private: 1999 ABIKind Kind; 2000 2001public: 2002 ARMABIInfo(CodeGenTypes &CGT, ABIKind _Kind) : ABIInfo(CGT), Kind(_Kind) {} 2003 2004private: 2005 ABIKind getABIKind() const { return Kind; } 2006 2007 ABIArgInfo classifyReturnType(QualType RetTy) const; 2008 ABIArgInfo classifyArgumentType(QualType RetTy) const; 2009 2010 virtual void computeInfo(CGFunctionInfo &FI) const; 2011 2012 virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 2013 CodeGenFunction &CGF) const; 2014}; 2015 2016class ARMTargetCodeGenInfo : public TargetCodeGenInfo { 2017public: 2018 ARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K) 2019 :TargetCodeGenInfo(new ARMABIInfo(CGT, K)) {} 2020 2021 int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const { 2022 return 13; 2023 } 2024}; 2025 2026} 2027 2028void ARMABIInfo::computeInfo(CGFunctionInfo &FI) const { 2029 FI.getReturnInfo() = classifyReturnType(FI.getReturnType()); 2030 for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end(); 2031 it != ie; ++it) 2032 it->info = classifyArgumentType(it->type); 2033 2034 const llvm::Triple &Triple(getContext().Target.getTriple()); 2035 llvm::CallingConv::ID DefaultCC; 2036 if (Triple.getEnvironmentName() == "gnueabi" || 2037 Triple.getEnvironmentName() == "eabi") 2038 DefaultCC = llvm::CallingConv::ARM_AAPCS; 2039 else 2040 DefaultCC = llvm::CallingConv::ARM_APCS; 2041 2042 switch (getABIKind()) { 2043 case APCS: 2044 if (DefaultCC != llvm::CallingConv::ARM_APCS) 2045 FI.setEffectiveCallingConvention(llvm::CallingConv::ARM_APCS); 2046 break; 2047 2048 case AAPCS: 2049 if (DefaultCC != llvm::CallingConv::ARM_AAPCS) 2050 FI.setEffectiveCallingConvention(llvm::CallingConv::ARM_AAPCS); 2051 break; 2052 2053 case AAPCS_VFP: 2054 FI.setEffectiveCallingConvention(llvm::CallingConv::ARM_AAPCS_VFP); 2055 break; 2056 } 2057} 2058 2059ABIArgInfo ARMABIInfo::classifyArgumentType(QualType Ty) const { 2060 if (!CodeGenFunction::hasAggregateLLVMType(Ty)) { 2061 // Treat an enum type as its underlying type. 2062 if (const EnumType *EnumTy = Ty->getAs<EnumType>()) 2063 Ty = EnumTy->getDecl()->getIntegerType(); 2064 2065 return (Ty->isPromotableIntegerType() ? 2066 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 2067 } 2068 2069 // Ignore empty records. 2070 if (isEmptyRecord(getContext(), Ty, true)) 2071 return ABIArgInfo::getIgnore(); 2072 2073 // Structures with either a non-trivial destructor or a non-trivial 2074 // copy constructor are always indirect. 2075 if (isRecordWithNonTrivialDestructorOrCopyConstructor(Ty)) 2076 return ABIArgInfo::getIndirect(0, /*ByVal=*/false); 2077 2078 // FIXME: This is kind of nasty... but there isn't much choice because the ARM 2079 // backend doesn't support byval. 2080 // FIXME: This doesn't handle alignment > 64 bits. 2081 const llvm::Type* ElemTy; 2082 unsigned SizeRegs; 2083 if (getContext().getTypeAlign(Ty) > 32) { 2084 ElemTy = llvm::Type::getInt64Ty(getVMContext()); 2085 SizeRegs = (getContext().getTypeSize(Ty) + 63) / 64; 2086 } else { 2087 ElemTy = llvm::Type::getInt32Ty(getVMContext()); 2088 SizeRegs = (getContext().getTypeSize(Ty) + 31) / 32; 2089 } 2090 std::vector<const llvm::Type*> LLVMFields; 2091 LLVMFields.push_back(llvm::ArrayType::get(ElemTy, SizeRegs)); 2092 const llvm::Type* STy = llvm::StructType::get(getVMContext(), LLVMFields, 2093 true); 2094 return ABIArgInfo::getDirect(STy); 2095} 2096 2097static bool isIntegerLikeType(QualType Ty, ASTContext &Context, 2098 llvm::LLVMContext &VMContext) { 2099 // APCS, C Language Calling Conventions, Non-Simple Return Values: A structure 2100 // is called integer-like if its size is less than or equal to one word, and 2101 // the offset of each of its addressable sub-fields is zero. 2102 2103 uint64_t Size = Context.getTypeSize(Ty); 2104 2105 // Check that the type fits in a word. 2106 if (Size > 32) 2107 return false; 2108 2109 // FIXME: Handle vector types! 2110 if (Ty->isVectorType()) 2111 return false; 2112 2113 // Float types are never treated as "integer like". 2114 if (Ty->isRealFloatingType()) 2115 return false; 2116 2117 // If this is a builtin or pointer type then it is ok. 2118 if (Ty->getAs<BuiltinType>() || Ty->isPointerType()) 2119 return true; 2120 2121 // Small complex integer types are "integer like". 2122 if (const ComplexType *CT = Ty->getAs<ComplexType>()) 2123 return isIntegerLikeType(CT->getElementType(), Context, VMContext); 2124 2125 // Single element and zero sized arrays should be allowed, by the definition 2126 // above, but they are not. 2127 2128 // Otherwise, it must be a record type. 2129 const RecordType *RT = Ty->getAs<RecordType>(); 2130 if (!RT) return false; 2131 2132 // Ignore records with flexible arrays. 2133 const RecordDecl *RD = RT->getDecl(); 2134 if (RD->hasFlexibleArrayMember()) 2135 return false; 2136 2137 // Check that all sub-fields are at offset 0, and are themselves "integer 2138 // like". 2139 const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD); 2140 2141 bool HadField = false; 2142 unsigned idx = 0; 2143 for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end(); 2144 i != e; ++i, ++idx) { 2145 const FieldDecl *FD = *i; 2146 2147 // Bit-fields are not addressable, we only need to verify they are "integer 2148 // like". We still have to disallow a subsequent non-bitfield, for example: 2149 // struct { int : 0; int x } 2150 // is non-integer like according to gcc. 2151 if (FD->isBitField()) { 2152 if (!RD->isUnion()) 2153 HadField = true; 2154 2155 if (!isIntegerLikeType(FD->getType(), Context, VMContext)) 2156 return false; 2157 2158 continue; 2159 } 2160 2161 // Check if this field is at offset 0. 2162 if (Layout.getFieldOffset(idx) != 0) 2163 return false; 2164 2165 if (!isIntegerLikeType(FD->getType(), Context, VMContext)) 2166 return false; 2167 2168 // Only allow at most one field in a structure. This doesn't match the 2169 // wording above, but follows gcc in situations with a field following an 2170 // empty structure. 2171 if (!RD->isUnion()) { 2172 if (HadField) 2173 return false; 2174 2175 HadField = true; 2176 } 2177 } 2178 2179 return true; 2180} 2181 2182ABIArgInfo ARMABIInfo::classifyReturnType(QualType RetTy) const { 2183 if (RetTy->isVoidType()) 2184 return ABIArgInfo::getIgnore(); 2185 2186 if (!CodeGenFunction::hasAggregateLLVMType(RetTy)) { 2187 // Treat an enum type as its underlying type. 2188 if (const EnumType *EnumTy = RetTy->getAs<EnumType>()) 2189 RetTy = EnumTy->getDecl()->getIntegerType(); 2190 2191 return (RetTy->isPromotableIntegerType() ? 2192 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 2193 } 2194 2195 // Structures with either a non-trivial destructor or a non-trivial 2196 // copy constructor are always indirect. 2197 if (isRecordWithNonTrivialDestructorOrCopyConstructor(RetTy)) 2198 return ABIArgInfo::getIndirect(0, /*ByVal=*/false); 2199 2200 // Are we following APCS? 2201 if (getABIKind() == APCS) { 2202 if (isEmptyRecord(getContext(), RetTy, false)) 2203 return ABIArgInfo::getIgnore(); 2204 2205 // Complex types are all returned as packed integers. 2206 // 2207 // FIXME: Consider using 2 x vector types if the back end handles them 2208 // correctly. 2209 if (RetTy->isAnyComplexType()) 2210 return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 2211 getContext().getTypeSize(RetTy))); 2212 2213 // Integer like structures are returned in r0. 2214 if (isIntegerLikeType(RetTy, getContext(), getVMContext())) { 2215 // Return in the smallest viable integer type. 2216 uint64_t Size = getContext().getTypeSize(RetTy); 2217 if (Size <= 8) 2218 return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext())); 2219 if (Size <= 16) 2220 return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext())); 2221 return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext())); 2222 } 2223 2224 // Otherwise return in memory. 2225 return ABIArgInfo::getIndirect(0); 2226 } 2227 2228 // Otherwise this is an AAPCS variant. 2229 2230 if (isEmptyRecord(getContext(), RetTy, true)) 2231 return ABIArgInfo::getIgnore(); 2232 2233 // Aggregates <= 4 bytes are returned in r0; other aggregates 2234 // are returned indirectly. 2235 uint64_t Size = getContext().getTypeSize(RetTy); 2236 if (Size <= 32) { 2237 // Return in the smallest viable integer type. 2238 if (Size <= 8) 2239 return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext())); 2240 if (Size <= 16) 2241 return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext())); 2242 return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext())); 2243 } 2244 2245 return ABIArgInfo::getIndirect(0); 2246} 2247 2248llvm::Value *ARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 2249 CodeGenFunction &CGF) const { 2250 // FIXME: Need to handle alignment 2251 const llvm::Type *BP = llvm::Type::getInt8PtrTy(CGF.getLLVMContext()); 2252 const llvm::Type *BPP = llvm::PointerType::getUnqual(BP); 2253 2254 CGBuilderTy &Builder = CGF.Builder; 2255 llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, 2256 "ap"); 2257 llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur"); 2258 llvm::Type *PTy = 2259 llvm::PointerType::getUnqual(CGF.ConvertType(Ty)); 2260 llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy); 2261 2262 uint64_t Offset = 2263 llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 4); 2264 llvm::Value *NextAddr = 2265 Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset), 2266 "ap.next"); 2267 Builder.CreateStore(NextAddr, VAListAddrAsBPP); 2268 2269 return AddrTyped; 2270} 2271 2272ABIArgInfo DefaultABIInfo::classifyReturnType(QualType RetTy) const { 2273 if (RetTy->isVoidType()) 2274 return ABIArgInfo::getIgnore(); 2275 2276 if (CodeGenFunction::hasAggregateLLVMType(RetTy)) 2277 return ABIArgInfo::getIndirect(0); 2278 2279 // Treat an enum type as its underlying type. 2280 if (const EnumType *EnumTy = RetTy->getAs<EnumType>()) 2281 RetTy = EnumTy->getDecl()->getIntegerType(); 2282 2283 return (RetTy->isPromotableIntegerType() ? 2284 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 2285} 2286 2287//===----------------------------------------------------------------------===// 2288// SystemZ ABI Implementation 2289//===----------------------------------------------------------------------===// 2290 2291namespace { 2292 2293class SystemZABIInfo : public ABIInfo { 2294public: 2295 SystemZABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {} 2296 2297 bool isPromotableIntegerType(QualType Ty) const; 2298 2299 ABIArgInfo classifyReturnType(QualType RetTy) const; 2300 ABIArgInfo classifyArgumentType(QualType RetTy) const; 2301 2302 virtual void computeInfo(CGFunctionInfo &FI) const { 2303 FI.getReturnInfo() = classifyReturnType(FI.getReturnType()); 2304 for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end(); 2305 it != ie; ++it) 2306 it->info = classifyArgumentType(it->type); 2307 } 2308 2309 virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 2310 CodeGenFunction &CGF) const; 2311}; 2312 2313class SystemZTargetCodeGenInfo : public TargetCodeGenInfo { 2314public: 2315 SystemZTargetCodeGenInfo(CodeGenTypes &CGT) 2316 : TargetCodeGenInfo(new SystemZABIInfo(CGT)) {} 2317}; 2318 2319} 2320 2321bool SystemZABIInfo::isPromotableIntegerType(QualType Ty) const { 2322 // SystemZ ABI requires all 8, 16 and 32 bit quantities to be extended. 2323 if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) 2324 switch (BT->getKind()) { 2325 case BuiltinType::Bool: 2326 case BuiltinType::Char_S: 2327 case BuiltinType::Char_U: 2328 case BuiltinType::SChar: 2329 case BuiltinType::UChar: 2330 case BuiltinType::Short: 2331 case BuiltinType::UShort: 2332 case BuiltinType::Int: 2333 case BuiltinType::UInt: 2334 return true; 2335 default: 2336 return false; 2337 } 2338 return false; 2339} 2340 2341llvm::Value *SystemZABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty, 2342 CodeGenFunction &CGF) const { 2343 // FIXME: Implement 2344 return 0; 2345} 2346 2347 2348ABIArgInfo SystemZABIInfo::classifyReturnType(QualType RetTy) const { 2349 if (RetTy->isVoidType()) 2350 return ABIArgInfo::getIgnore(); 2351 if (CodeGenFunction::hasAggregateLLVMType(RetTy)) 2352 return ABIArgInfo::getIndirect(0); 2353 2354 return (isPromotableIntegerType(RetTy) ? 2355 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 2356} 2357 2358ABIArgInfo SystemZABIInfo::classifyArgumentType(QualType Ty) const { 2359 if (CodeGenFunction::hasAggregateLLVMType(Ty)) 2360 return ABIArgInfo::getIndirect(0); 2361 2362 return (isPromotableIntegerType(Ty) ? 2363 ABIArgInfo::getExtend() : ABIArgInfo::getDirect()); 2364} 2365 2366//===----------------------------------------------------------------------===// 2367// MSP430 ABI Implementation 2368//===----------------------------------------------------------------------===// 2369 2370namespace { 2371 2372class MSP430TargetCodeGenInfo : public TargetCodeGenInfo { 2373public: 2374 MSP430TargetCodeGenInfo(CodeGenTypes &CGT) 2375 : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {} 2376 void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV, 2377 CodeGen::CodeGenModule &M) const; 2378}; 2379 2380} 2381 2382void MSP430TargetCodeGenInfo::SetTargetAttributes(const Decl *D, 2383 llvm::GlobalValue *GV, 2384 CodeGen::CodeGenModule &M) const { 2385 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 2386 if (const MSP430InterruptAttr *attr = FD->getAttr<MSP430InterruptAttr>()) { 2387 // Handle 'interrupt' attribute: 2388 llvm::Function *F = cast<llvm::Function>(GV); 2389 2390 // Step 1: Set ISR calling convention. 2391 F->setCallingConv(llvm::CallingConv::MSP430_INTR); 2392 2393 // Step 2: Add attributes goodness. 2394 F->addFnAttr(llvm::Attribute::NoInline); 2395 2396 // Step 3: Emit ISR vector alias. 2397 unsigned Num = attr->getNumber() + 0xffe0; 2398 new llvm::GlobalAlias(GV->getType(), llvm::Function::ExternalLinkage, 2399 "vector_" + 2400 llvm::LowercaseString(llvm::utohexstr(Num)), 2401 GV, &M.getModule()); 2402 } 2403 } 2404} 2405 2406//===----------------------------------------------------------------------===// 2407// MIPS ABI Implementation. This works for both little-endian and 2408// big-endian variants. 2409//===----------------------------------------------------------------------===// 2410 2411namespace { 2412class MIPSTargetCodeGenInfo : public TargetCodeGenInfo { 2413public: 2414 MIPSTargetCodeGenInfo(CodeGenTypes &CGT) 2415 : TargetCodeGenInfo(new DefaultABIInfo(CGT)) {} 2416 2417 int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const { 2418 return 29; 2419 } 2420 2421 bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF, 2422 llvm::Value *Address) const; 2423}; 2424} 2425 2426bool 2427MIPSTargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF, 2428 llvm::Value *Address) const { 2429 // This information comes from gcc's implementation, which seems to 2430 // as canonical as it gets. 2431 2432 CodeGen::CGBuilderTy &Builder = CGF.Builder; 2433 llvm::LLVMContext &Context = CGF.getLLVMContext(); 2434 2435 // Everything on MIPS is 4 bytes. Double-precision FP registers 2436 // are aliased to pairs of single-precision FP registers. 2437 const llvm::IntegerType *i8 = llvm::Type::getInt8Ty(Context); 2438 llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4); 2439 2440 // 0-31 are the general purpose registers, $0 - $31. 2441 // 32-63 are the floating-point registers, $f0 - $f31. 2442 // 64 and 65 are the multiply/divide registers, $hi and $lo. 2443 // 66 is the (notional, I think) register for signal-handler return. 2444 AssignToArrayRange(Builder, Address, Four8, 0, 65); 2445 2446 // 67-74 are the floating-point status registers, $fcc0 - $fcc7. 2447 // They are one bit wide and ignored here. 2448 2449 // 80-111 are the coprocessor 0 registers, $c0r0 - $c0r31. 2450 // (coprocessor 1 is the FP unit) 2451 // 112-143 are the coprocessor 2 registers, $c2r0 - $c2r31. 2452 // 144-175 are the coprocessor 3 registers, $c3r0 - $c3r31. 2453 // 176-181 are the DSP accumulator registers. 2454 AssignToArrayRange(Builder, Address, Four8, 80, 181); 2455 2456 return false; 2457} 2458 2459 2460const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() { 2461 if (TheTargetCodeGenInfo) 2462 return *TheTargetCodeGenInfo; 2463 2464 // For now we just cache the TargetCodeGenInfo in CodeGenModule and don't 2465 // free it. 2466 2467 const llvm::Triple &Triple = getContext().Target.getTriple(); 2468 switch (Triple.getArch()) { 2469 default: 2470 return *(TheTargetCodeGenInfo = new DefaultTargetCodeGenInfo(Types)); 2471 2472 case llvm::Triple::mips: 2473 case llvm::Triple::mipsel: 2474 return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types)); 2475 2476 case llvm::Triple::arm: 2477 case llvm::Triple::thumb: 2478 // FIXME: We want to know the float calling convention as well. 2479 if (strcmp(getContext().Target.getABI(), "apcs-gnu") == 0) 2480 return *(TheTargetCodeGenInfo = 2481 new ARMTargetCodeGenInfo(Types, ARMABIInfo::APCS)); 2482 2483 return *(TheTargetCodeGenInfo = 2484 new ARMTargetCodeGenInfo(Types, ARMABIInfo::AAPCS)); 2485 2486 case llvm::Triple::pic16: 2487 return *(TheTargetCodeGenInfo = new PIC16TargetCodeGenInfo(Types)); 2488 2489 case llvm::Triple::ppc: 2490 return *(TheTargetCodeGenInfo = new PPC32TargetCodeGenInfo(Types)); 2491 2492 case llvm::Triple::systemz: 2493 return *(TheTargetCodeGenInfo = new SystemZTargetCodeGenInfo(Types)); 2494 2495 case llvm::Triple::msp430: 2496 return *(TheTargetCodeGenInfo = new MSP430TargetCodeGenInfo(Types)); 2497 2498 case llvm::Triple::x86: 2499 switch (Triple.getOS()) { 2500 case llvm::Triple::Darwin: 2501 return *(TheTargetCodeGenInfo = 2502 new X86_32TargetCodeGenInfo(Types, true, true)); 2503 case llvm::Triple::Cygwin: 2504 case llvm::Triple::MinGW32: 2505 case llvm::Triple::MinGW64: 2506 case llvm::Triple::AuroraUX: 2507 case llvm::Triple::DragonFly: 2508 case llvm::Triple::FreeBSD: 2509 case llvm::Triple::OpenBSD: 2510 return *(TheTargetCodeGenInfo = 2511 new X86_32TargetCodeGenInfo(Types, false, true)); 2512 2513 default: 2514 return *(TheTargetCodeGenInfo = 2515 new X86_32TargetCodeGenInfo(Types, false, false)); 2516 } 2517 2518 case llvm::Triple::x86_64: 2519 return *(TheTargetCodeGenInfo = new X86_64TargetCodeGenInfo(Types)); 2520 } 2521} 2522