1 //===--- TargetInfo.h - Expose information about the target -----*- 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 /// \file 11 /// \brief Defines the clang::TargetInfo interface. 12 /// 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_CLANG_BASIC_TARGETINFO_H 16 #define LLVM_CLANG_BASIC_TARGETINFO_H 17 18 #include "clang/Basic/AddressSpaces.h" 19 #include "clang/Basic/TargetCXXABI.h" 20 #include "clang/Basic/LLVM.h" 21 #include "clang/Basic/Specifiers.h" 22 #include "clang/Basic/TargetOptions.h" 23 #include "clang/Basic/VersionTuple.h" 24 #include "llvm/ADT/IntrusiveRefCntPtr.h" 25 #include "llvm/ADT/StringMap.h" 26 #include "llvm/ADT/StringRef.h" 27 #include "llvm/ADT/StringSwitch.h" 28 #include "llvm/ADT/Triple.h" 29 #include "llvm/Support/DataTypes.h" 30 #include <cassert> 31 #include <string> 32 #include <vector> 33 34 namespace llvm { 35 struct fltSemantics; 36 } 37 38 namespace clang { 39 class DiagnosticsEngine; 40 class LangOptions; 41 class MacroBuilder; 42 class SourceLocation; 43 class SourceManager; 44 45 namespace Builtin { struct Info; } 46 47 /// \brief Exposes information about the current target. 48 /// 49 class TargetInfo : public RefCountedBase<TargetInfo> { 50 IntrusiveRefCntPtr<TargetOptions> TargetOpts; 51 llvm::Triple Triple; 52 protected: 53 // Target values set by the ctor of the actual target implementation. Default 54 // values are specified by the TargetInfo constructor. 55 bool BigEndian; 56 bool TLSSupported; 57 bool NoAsmVariants; // True if {|} are normal characters. 58 unsigned char PointerWidth, PointerAlign; 59 unsigned char BoolWidth, BoolAlign; 60 unsigned char IntWidth, IntAlign; 61 unsigned char HalfWidth, HalfAlign; 62 unsigned char FloatWidth, FloatAlign; 63 unsigned char DoubleWidth, DoubleAlign; 64 unsigned char LongDoubleWidth, LongDoubleAlign; 65 unsigned char LargeArrayMinWidth, LargeArrayAlign; 66 unsigned char LongWidth, LongAlign; 67 unsigned char LongLongWidth, LongLongAlign; 68 unsigned char SuitableAlign; 69 unsigned char MinGlobalAlign; 70 unsigned char MaxAtomicPromoteWidth, MaxAtomicInlineWidth; 71 unsigned short MaxVectorAlign; 72 const char *DescriptionString; 73 const char *UserLabelPrefix; 74 const char *MCountName; 75 const llvm::fltSemantics *HalfFormat, *FloatFormat, *DoubleFormat, 76 *LongDoubleFormat; 77 unsigned char RegParmMax, SSERegParmMax; 78 TargetCXXABI TheCXXABI; 79 const LangAS::Map *AddrSpaceMap; 80 81 mutable StringRef PlatformName; 82 mutable VersionTuple PlatformMinVersion; 83 84 unsigned HasAlignMac68kSupport : 1; 85 unsigned RealTypeUsesObjCFPRet : 3; 86 unsigned ComplexLongDoubleUsesFP2Ret : 1; 87 88 // TargetInfo Constructor. Default initializes all fields. 89 TargetInfo(const llvm::Triple &T); 90 91 public: 92 /// \brief Construct a target for the given options. 93 /// 94 /// \param Opts - The options to use to initialize the target. The target may 95 /// modify the options to canonicalize the target feature information to match 96 /// what the backend expects. 97 static TargetInfo* CreateTargetInfo(DiagnosticsEngine &Diags, 98 TargetOptions *Opts); 99 100 virtual ~TargetInfo(); 101 102 /// \brief Retrieve the target options. 103 TargetOptions &getTargetOpts() const { 104 assert(TargetOpts && "Missing target options"); 105 return *TargetOpts; 106 } 107 108 void setTargetOpts(TargetOptions *TargetOpts) { 109 this->TargetOpts = TargetOpts; 110 } 111 112 ///===---- Target Data Type Query Methods -------------------------------===// 113 enum IntType { 114 NoInt = 0, 115 SignedShort, 116 UnsignedShort, 117 SignedInt, 118 UnsignedInt, 119 SignedLong, 120 UnsignedLong, 121 SignedLongLong, 122 UnsignedLongLong 123 }; 124 125 enum RealType { 126 Float = 0, 127 Double, 128 LongDouble 129 }; 130 131 /// \brief The different kinds of __builtin_va_list types defined by 132 /// the target implementation. 133 enum BuiltinVaListKind { 134 /// typedef char* __builtin_va_list; 135 CharPtrBuiltinVaList = 0, 136 137 /// typedef void* __builtin_va_list; 138 VoidPtrBuiltinVaList, 139 140 /// __builtin_va_list as defind by the AArch64 ABI 141 /// http://infocenter.arm.com/help/topic/com.arm.doc.ihi0055a/IHI0055A_aapcs64.pdf 142 AArch64ABIBuiltinVaList, 143 144 /// __builtin_va_list as defined by the PNaCl ABI: 145 /// http://www.chromium.org/nativeclient/pnacl/bitcode-abi#TOC-Machine-Types 146 PNaClABIBuiltinVaList, 147 148 /// __builtin_va_list as defined by the Power ABI: 149 /// https://www.power.org 150 /// /resources/downloads/Power-Arch-32-bit-ABI-supp-1.0-Embedded.pdf 151 PowerABIBuiltinVaList, 152 153 /// __builtin_va_list as defined by the x86-64 ABI: 154 /// http://www.x86-64.org/documentation/abi.pdf 155 X86_64ABIBuiltinVaList, 156 157 /// __builtin_va_list as defined by ARM AAPCS ABI 158 /// http://infocenter.arm.com 159 // /help/topic/com.arm.doc.ihi0042d/IHI0042D_aapcs.pdf 160 AAPCSABIBuiltinVaList, 161 162 // typedef struct __va_list_tag 163 // { 164 // long __gpr; 165 // long __fpr; 166 // void *__overflow_arg_area; 167 // void *__reg_save_area; 168 // } va_list[1]; 169 SystemZBuiltinVaList 170 }; 171 172 protected: 173 IntType SizeType, IntMaxType, UIntMaxType, PtrDiffType, IntPtrType, WCharType, 174 WIntType, Char16Type, Char32Type, Int64Type, SigAtomicType, 175 ProcessIDType; 176 177 /// \brief Whether Objective-C's built-in boolean type should be signed char. 178 /// 179 /// Otherwise, when this flag is not set, the normal built-in boolean type is 180 /// used. 181 unsigned UseSignedCharForObjCBool : 1; 182 183 /// Control whether the alignment of bit-field types is respected when laying 184 /// out structures. If true, then the alignment of the bit-field type will be 185 /// used to (a) impact the alignment of the containing structure, and (b) 186 /// ensure that the individual bit-field will not straddle an alignment 187 /// boundary. 188 unsigned UseBitFieldTypeAlignment : 1; 189 190 /// \brief Whether zero length bitfields (e.g., int : 0;) force alignment of 191 /// the next bitfield. 192 /// 193 /// If the alignment of the zero length bitfield is greater than the member 194 /// that follows it, `bar', `bar' will be aligned as the type of the 195 /// zero-length bitfield. 196 unsigned UseZeroLengthBitfieldAlignment : 1; 197 198 /// If non-zero, specifies a fixed alignment value for bitfields that follow 199 /// zero length bitfield, regardless of the zero length bitfield type. 200 unsigned ZeroLengthBitfieldBoundary; 201 202 public: 203 IntType getSizeType() const { return SizeType; } 204 IntType getIntMaxType() const { return IntMaxType; } 205 IntType getUIntMaxType() const { return UIntMaxType; } 206 IntType getPtrDiffType(unsigned AddrSpace) const { 207 return AddrSpace == 0 ? PtrDiffType : getPtrDiffTypeV(AddrSpace); 208 } 209 IntType getIntPtrType() const { return IntPtrType; } 210 IntType getWCharType() const { return WCharType; } 211 IntType getWIntType() const { return WIntType; } 212 IntType getChar16Type() const { return Char16Type; } 213 IntType getChar32Type() const { return Char32Type; } 214 IntType getInt64Type() const { return Int64Type; } 215 IntType getSigAtomicType() const { return SigAtomicType; } 216 IntType getProcessIDType() const { return ProcessIDType; } 217 218 /// \brief Return the width (in bits) of the specified integer type enum. 219 /// 220 /// For example, SignedInt -> getIntWidth(). 221 unsigned getTypeWidth(IntType T) const; 222 223 /// \brief Return the alignment (in bits) of the specified integer type enum. 224 /// 225 /// For example, SignedInt -> getIntAlign(). 226 unsigned getTypeAlign(IntType T) const; 227 228 /// \brief Returns true if the type is signed; false otherwise. 229 static bool isTypeSigned(IntType T); 230 231 /// \brief Return the width of pointers on this target, for the 232 /// specified address space. 233 uint64_t getPointerWidth(unsigned AddrSpace) const { 234 return AddrSpace == 0 ? PointerWidth : getPointerWidthV(AddrSpace); 235 } 236 uint64_t getPointerAlign(unsigned AddrSpace) const { 237 return AddrSpace == 0 ? PointerAlign : getPointerAlignV(AddrSpace); 238 } 239 240 /// \brief Return the size of '_Bool' and C++ 'bool' for this target, in bits. 241 unsigned getBoolWidth() const { return BoolWidth; } 242 243 /// \brief Return the alignment of '_Bool' and C++ 'bool' for this target. 244 unsigned getBoolAlign() const { return BoolAlign; } 245 246 unsigned getCharWidth() const { return 8; } // FIXME 247 unsigned getCharAlign() const { return 8; } // FIXME 248 249 /// \brief Return the size of 'signed short' and 'unsigned short' for this 250 /// target, in bits. 251 unsigned getShortWidth() const { return 16; } // FIXME 252 253 /// \brief Return the alignment of 'signed short' and 'unsigned short' for 254 /// this target. 255 unsigned getShortAlign() const { return 16; } // FIXME 256 257 /// getIntWidth/Align - Return the size of 'signed int' and 'unsigned int' for 258 /// this target, in bits. 259 unsigned getIntWidth() const { return IntWidth; } 260 unsigned getIntAlign() const { return IntAlign; } 261 262 /// getLongWidth/Align - Return the size of 'signed long' and 'unsigned long' 263 /// for this target, in bits. 264 unsigned getLongWidth() const { return LongWidth; } 265 unsigned getLongAlign() const { return LongAlign; } 266 267 /// getLongLongWidth/Align - Return the size of 'signed long long' and 268 /// 'unsigned long long' for this target, in bits. 269 unsigned getLongLongWidth() const { return LongLongWidth; } 270 unsigned getLongLongAlign() const { return LongLongAlign; } 271 272 /// \brief Determine whether the __int128 type is supported on this target. 273 bool hasInt128Type() const { return getPointerWidth(0) >= 64; } // FIXME 274 275 /// \brief Return the alignment that is suitable for storing any 276 /// object with a fundamental alignment requirement. 277 unsigned getSuitableAlign() const { return SuitableAlign; } 278 279 /// getMinGlobalAlign - Return the minimum alignment of a global variable, 280 /// unless its alignment is explicitly reduced via attributes. 281 unsigned getMinGlobalAlign() const { return MinGlobalAlign; } 282 283 /// getWCharWidth/Align - Return the size of 'wchar_t' for this target, in 284 /// bits. 285 unsigned getWCharWidth() const { return getTypeWidth(WCharType); } 286 unsigned getWCharAlign() const { return getTypeAlign(WCharType); } 287 288 /// getChar16Width/Align - Return the size of 'char16_t' for this target, in 289 /// bits. 290 unsigned getChar16Width() const { return getTypeWidth(Char16Type); } 291 unsigned getChar16Align() const { return getTypeAlign(Char16Type); } 292 293 /// getChar32Width/Align - Return the size of 'char32_t' for this target, in 294 /// bits. 295 unsigned getChar32Width() const { return getTypeWidth(Char32Type); } 296 unsigned getChar32Align() const { return getTypeAlign(Char32Type); } 297 298 /// getHalfWidth/Align/Format - Return the size/align/format of 'half'. 299 unsigned getHalfWidth() const { return HalfWidth; } 300 unsigned getHalfAlign() const { return HalfAlign; } 301 const llvm::fltSemantics &getHalfFormat() const { return *HalfFormat; } 302 303 /// getFloatWidth/Align/Format - Return the size/align/format of 'float'. 304 unsigned getFloatWidth() const { return FloatWidth; } 305 unsigned getFloatAlign() const { return FloatAlign; } 306 const llvm::fltSemantics &getFloatFormat() const { return *FloatFormat; } 307 308 /// getDoubleWidth/Align/Format - Return the size/align/format of 'double'. 309 unsigned getDoubleWidth() const { return DoubleWidth; } 310 unsigned getDoubleAlign() const { return DoubleAlign; } 311 const llvm::fltSemantics &getDoubleFormat() const { return *DoubleFormat; } 312 313 /// getLongDoubleWidth/Align/Format - Return the size/align/format of 'long 314 /// double'. 315 unsigned getLongDoubleWidth() const { return LongDoubleWidth; } 316 unsigned getLongDoubleAlign() const { return LongDoubleAlign; } 317 const llvm::fltSemantics &getLongDoubleFormat() const { 318 return *LongDoubleFormat; 319 } 320 321 /// \brief Return the value for the C99 FLT_EVAL_METHOD macro. 322 virtual unsigned getFloatEvalMethod() const { return 0; } 323 324 // getLargeArrayMinWidth/Align - Return the minimum array size that is 325 // 'large' and its alignment. 326 unsigned getLargeArrayMinWidth() const { return LargeArrayMinWidth; } 327 unsigned getLargeArrayAlign() const { return LargeArrayAlign; } 328 329 /// \brief Return the maximum width lock-free atomic operation which will 330 /// ever be supported for the given target 331 unsigned getMaxAtomicPromoteWidth() const { return MaxAtomicPromoteWidth; } 332 /// \brief Return the maximum width lock-free atomic operation which can be 333 /// inlined given the supported features of the given target. 334 unsigned getMaxAtomicInlineWidth() const { return MaxAtomicInlineWidth; } 335 336 /// \brief Return the maximum vector alignment supported for the given target. 337 unsigned getMaxVectorAlign() const { return MaxVectorAlign; } 338 339 /// \brief Return the size of intmax_t and uintmax_t for this target, in bits. 340 unsigned getIntMaxTWidth() const { 341 return getTypeWidth(IntMaxType); 342 } 343 344 // Return the size of unwind_word for this target. 345 unsigned getUnwindWordWidth() const { return getPointerWidth(0); } 346 347 /// \brief Return the "preferred" register width on this target. 348 uint64_t getRegisterWidth() const { 349 // Currently we assume the register width on the target matches the pointer 350 // width, we can introduce a new variable for this if/when some target wants 351 // it. 352 return LongWidth; 353 } 354 355 /// \brief Returns the default value of the __USER_LABEL_PREFIX__ macro, 356 /// which is the prefix given to user symbols by default. 357 /// 358 /// On most platforms this is "_", but it is "" on some, and "." on others. 359 const char *getUserLabelPrefix() const { 360 return UserLabelPrefix; 361 } 362 363 /// \brief Returns the name of the mcount instrumentation function. 364 const char *getMCountName() const { 365 return MCountName; 366 } 367 368 /// \brief Check if the Objective-C built-in boolean type should be signed 369 /// char. 370 /// 371 /// Otherwise, if this returns false, the normal built-in boolean type 372 /// should also be used for Objective-C. 373 bool useSignedCharForObjCBool() const { 374 return UseSignedCharForObjCBool; 375 } 376 void noSignedCharForObjCBool() { 377 UseSignedCharForObjCBool = false; 378 } 379 380 /// \brief Check whether the alignment of bit-field types is respected 381 /// when laying out structures. 382 bool useBitFieldTypeAlignment() const { 383 return UseBitFieldTypeAlignment; 384 } 385 386 /// \brief Check whether zero length bitfields should force alignment of 387 /// the next member. 388 bool useZeroLengthBitfieldAlignment() const { 389 return UseZeroLengthBitfieldAlignment; 390 } 391 392 /// \brief Get the fixed alignment value in bits for a member that follows 393 /// a zero length bitfield. 394 unsigned getZeroLengthBitfieldBoundary() const { 395 return ZeroLengthBitfieldBoundary; 396 } 397 398 /// \brief Check whether this target support '\#pragma options align=mac68k'. 399 bool hasAlignMac68kSupport() const { 400 return HasAlignMac68kSupport; 401 } 402 403 /// \brief Return the user string for the specified integer type enum. 404 /// 405 /// For example, SignedShort -> "short". 406 static const char *getTypeName(IntType T); 407 408 /// \brief Return the constant suffix for the specified integer type enum. 409 /// 410 /// For example, SignedLong -> "L". 411 static const char *getTypeConstantSuffix(IntType T); 412 413 /// \brief Check whether the given real type should use the "fpret" flavor of 414 /// Objective-C message passing on this target. 415 bool useObjCFPRetForRealType(RealType T) const { 416 return RealTypeUsesObjCFPRet & (1 << T); 417 } 418 419 /// \brief Check whether _Complex long double should use the "fp2ret" flavor 420 /// of Objective-C message passing on this target. 421 bool useObjCFP2RetForComplexLongDouble() const { 422 return ComplexLongDoubleUsesFP2Ret; 423 } 424 425 ///===---- Other target property query methods --------------------------===// 426 427 /// \brief Appends the target-specific \#define values for this 428 /// target set to the specified buffer. 429 virtual void getTargetDefines(const LangOptions &Opts, 430 MacroBuilder &Builder) const = 0; 431 432 433 /// Return information about target-specific builtins for 434 /// the current primary target, and info about which builtins are non-portable 435 /// across the current set of primary and secondary targets. 436 virtual void getTargetBuiltins(const Builtin::Info *&Records, 437 unsigned &NumRecords) const = 0; 438 439 /// The __builtin_clz* and __builtin_ctz* built-in 440 /// functions are specified to have undefined results for zero inputs, but 441 /// on targets that support these operations in a way that provides 442 /// well-defined results for zero without loss of performance, it is a good 443 /// idea to avoid optimizing based on that undef behavior. 444 virtual bool isCLZForZeroUndef() const { return true; } 445 446 /// \brief Returns the kind of __builtin_va_list type that should be used 447 /// with this target. 448 virtual BuiltinVaListKind getBuiltinVaListKind() const = 0; 449 450 /// \brief Returns whether the passed in string is a valid clobber in an 451 /// inline asm statement. 452 /// 453 /// This is used by Sema. 454 bool isValidClobber(StringRef Name) const; 455 456 /// \brief Returns whether the passed in string is a valid register name 457 /// according to GCC. 458 /// 459 /// This is used by Sema for inline asm statements. 460 bool isValidGCCRegisterName(StringRef Name) const; 461 462 /// \brief Returns the "normalized" GCC register name. 463 /// 464 /// For example, on x86 it will return "ax" when "eax" is passed in. 465 StringRef getNormalizedGCCRegisterName(StringRef Name) const; 466 467 struct ConstraintInfo { 468 enum { 469 CI_None = 0x00, 470 CI_AllowsMemory = 0x01, 471 CI_AllowsRegister = 0x02, 472 CI_ReadWrite = 0x04, // "+r" output constraint (read and write). 473 CI_HasMatchingInput = 0x08 // This output operand has a matching input. 474 }; 475 unsigned Flags; 476 int TiedOperand; 477 478 std::string ConstraintStr; // constraint: "=rm" 479 std::string Name; // Operand name: [foo] with no []'s. 480 public: 481 ConstraintInfo(StringRef ConstraintStr, StringRef Name) 482 : Flags(0), TiedOperand(-1), ConstraintStr(ConstraintStr.str()), 483 Name(Name.str()) {} 484 485 const std::string &getConstraintStr() const { return ConstraintStr; } 486 const std::string &getName() const { return Name; } 487 bool isReadWrite() const { return (Flags & CI_ReadWrite) != 0; } 488 bool allowsRegister() const { return (Flags & CI_AllowsRegister) != 0; } 489 bool allowsMemory() const { return (Flags & CI_AllowsMemory) != 0; } 490 491 /// \brief Return true if this output operand has a matching 492 /// (tied) input operand. 493 bool hasMatchingInput() const { return (Flags & CI_HasMatchingInput) != 0; } 494 495 /// \brief Return true if this input operand is a matching 496 /// constraint that ties it to an output operand. 497 /// 498 /// If this returns true then getTiedOperand will indicate which output 499 /// operand this is tied to. 500 bool hasTiedOperand() const { return TiedOperand != -1; } 501 unsigned getTiedOperand() const { 502 assert(hasTiedOperand() && "Has no tied operand!"); 503 return (unsigned)TiedOperand; 504 } 505 506 void setIsReadWrite() { Flags |= CI_ReadWrite; } 507 void setAllowsMemory() { Flags |= CI_AllowsMemory; } 508 void setAllowsRegister() { Flags |= CI_AllowsRegister; } 509 void setHasMatchingInput() { Flags |= CI_HasMatchingInput; } 510 511 /// \brief Indicate that this is an input operand that is tied to 512 /// the specified output operand. 513 /// 514 /// Copy over the various constraint information from the output. 515 void setTiedOperand(unsigned N, ConstraintInfo &Output) { 516 Output.setHasMatchingInput(); 517 Flags = Output.Flags; 518 TiedOperand = N; 519 // Don't copy Name or constraint string. 520 } 521 }; 522 523 // validateOutputConstraint, validateInputConstraint - Checks that 524 // a constraint is valid and provides information about it. 525 // FIXME: These should return a real error instead of just true/false. 526 bool validateOutputConstraint(ConstraintInfo &Info) const; 527 bool validateInputConstraint(ConstraintInfo *OutputConstraints, 528 unsigned NumOutputs, 529 ConstraintInfo &info) const; 530 virtual bool validateInputSize(StringRef /*Constraint*/, 531 unsigned /*Size*/) const { 532 return true; 533 } 534 virtual bool validateConstraintModifier(StringRef /*Constraint*/, 535 const char /*Modifier*/, 536 unsigned /*Size*/) const { 537 return true; 538 } 539 bool resolveSymbolicName(const char *&Name, 540 ConstraintInfo *OutputConstraints, 541 unsigned NumOutputs, unsigned &Index) const; 542 543 // Constraint parm will be left pointing at the last character of 544 // the constraint. In practice, it won't be changed unless the 545 // constraint is longer than one character. 546 virtual std::string convertConstraint(const char *&Constraint) const { 547 // 'p' defaults to 'r', but can be overridden by targets. 548 if (*Constraint == 'p') 549 return std::string("r"); 550 return std::string(1, *Constraint); 551 } 552 553 /// \brief Returns a string of target-specific clobbers, in LLVM format. 554 virtual const char *getClobbers() const = 0; 555 556 557 /// \brief Returns the target triple of the primary target. 558 const llvm::Triple &getTriple() const { 559 return Triple; 560 } 561 562 const char *getTargetDescription() const { 563 return DescriptionString; 564 } 565 566 struct GCCRegAlias { 567 const char * const Aliases[5]; 568 const char * const Register; 569 }; 570 571 struct AddlRegName { 572 const char * const Names[5]; 573 const unsigned RegNum; 574 }; 575 576 /// \brief Does this target support "protected" visibility? 577 /// 578 /// Any target which dynamic libraries will naturally support 579 /// something like "default" (meaning that the symbol is visible 580 /// outside this shared object) and "hidden" (meaning that it isn't) 581 /// visibilities, but "protected" is really an ELF-specific concept 582 /// with weird semantics designed around the convenience of dynamic 583 /// linker implementations. Which is not to suggest that there's 584 /// consistent target-independent semantics for "default" visibility 585 /// either; the entire thing is pretty badly mangled. 586 virtual bool hasProtectedVisibility() const { return true; } 587 588 /// \brief Return the section to use for CFString literals, or 0 if no 589 /// special section is used. 590 virtual const char *getCFStringSection() const { 591 return "__DATA,__cfstring"; 592 } 593 594 /// \brief Return the section to use for NSString literals, or 0 if no 595 /// special section is used. 596 virtual const char *getNSStringSection() const { 597 return "__OBJC,__cstring_object,regular,no_dead_strip"; 598 } 599 600 /// \brief Return the section to use for NSString literals, or 0 if no 601 /// special section is used (NonFragile ABI). 602 virtual const char *getNSStringNonFragileABISection() const { 603 return "__DATA, __objc_stringobj, regular, no_dead_strip"; 604 } 605 606 /// \brief An optional hook that targets can implement to perform semantic 607 /// checking on attribute((section("foo"))) specifiers. 608 /// 609 /// In this case, "foo" is passed in to be checked. If the section 610 /// specifier is invalid, the backend should return a non-empty string 611 /// that indicates the problem. 612 /// 613 /// This hook is a simple quality of implementation feature to catch errors 614 /// and give good diagnostics in cases when the assembler or code generator 615 /// would otherwise reject the section specifier. 616 /// 617 virtual std::string isValidSectionSpecifier(StringRef SR) const { 618 return ""; 619 } 620 621 /// \brief Set forced language options. 622 /// 623 /// Apply changes to the target information with respect to certain 624 /// language options which change the target configuration. 625 virtual void setForcedLangOptions(LangOptions &Opts); 626 627 /// \brief Get the default set of target features for the CPU; 628 /// this should include all legal feature strings on the target. 629 virtual void getDefaultFeatures(llvm::StringMap<bool> &Features) const { 630 } 631 632 /// \brief Get the ABI currently in use. 633 virtual const char *getABI() const { 634 return ""; 635 } 636 637 /// \brief Get the C++ ABI currently in use. 638 TargetCXXABI getCXXABI() const { 639 return TheCXXABI; 640 } 641 642 /// \brief Target the specified CPU. 643 /// 644 /// \return False on error (invalid CPU name). 645 virtual bool setCPU(const std::string &Name) { 646 return false; 647 } 648 649 /// \brief Use the specified ABI. 650 /// 651 /// \return False on error (invalid ABI name). 652 virtual bool setABI(const std::string &Name) { 653 return false; 654 } 655 656 /// \brief Use this specified C++ ABI. 657 /// 658 /// \return False on error (invalid C++ ABI name). 659 bool setCXXABI(llvm::StringRef name) { 660 TargetCXXABI ABI; 661 if (!ABI.tryParse(name)) return false; 662 return setCXXABI(ABI); 663 } 664 665 /// \brief Set the C++ ABI to be used by this implementation. 666 /// 667 /// \return False on error (ABI not valid on this target) 668 virtual bool setCXXABI(TargetCXXABI ABI) { 669 TheCXXABI = ABI; 670 return true; 671 } 672 673 /// \brief Enable or disable a specific target feature; 674 /// the feature name must be valid. 675 /// 676 /// \return False on error (invalid feature name). 677 virtual bool setFeatureEnabled(llvm::StringMap<bool> &Features, 678 StringRef Name, 679 bool Enabled) const { 680 return false; 681 } 682 683 /// \brief Perform initialization based on the user configured 684 /// set of features (e.g., +sse4). 685 /// 686 /// The list is guaranteed to have at most one entry per feature. 687 /// 688 /// The target may modify the features list, to change which options are 689 /// passed onwards to the backend. 690 virtual void HandleTargetFeatures(std::vector<std::string> &Features) { 691 } 692 693 /// \brief Determine whether the given target has the given feature. 694 virtual bool hasFeature(StringRef Feature) const { 695 return false; 696 } 697 698 // \brief Returns maximal number of args passed in registers. 699 unsigned getRegParmMax() const { 700 assert(RegParmMax < 7 && "RegParmMax value is larger than AST can handle"); 701 return RegParmMax; 702 } 703 704 /// \brief Whether the target supports thread-local storage. 705 bool isTLSSupported() const { 706 return TLSSupported; 707 } 708 709 /// \brief Return true if {|} are normal characters in the asm string. 710 /// 711 /// If this returns false (the default), then {abc|xyz} is syntax 712 /// that says that when compiling for asm variant #0, "abc" should be 713 /// generated, but when compiling for asm variant #1, "xyz" should be 714 /// generated. 715 bool hasNoAsmVariants() const { 716 return NoAsmVariants; 717 } 718 719 /// \brief Return the register number that __builtin_eh_return_regno would 720 /// return with the specified argument. 721 virtual int getEHDataRegisterNumber(unsigned RegNo) const { 722 return -1; 723 } 724 725 /// \brief Return the section to use for C++ static initialization functions. 726 virtual const char *getStaticInitSectionSpecifier() const { 727 return 0; 728 } 729 730 const LangAS::Map &getAddressSpaceMap() const { 731 return *AddrSpaceMap; 732 } 733 734 /// \brief Retrieve the name of the platform as it is used in the 735 /// availability attribute. 736 StringRef getPlatformName() const { return PlatformName; } 737 738 /// \brief Retrieve the minimum desired version of the platform, to 739 /// which the program should be compiled. 740 VersionTuple getPlatformMinVersion() const { return PlatformMinVersion; } 741 742 bool isBigEndian() const { return BigEndian; } 743 744 enum CallingConvMethodType { 745 CCMT_Unknown, 746 CCMT_Member, 747 CCMT_NonMember 748 }; 749 750 /// \brief Gets the default calling convention for the given target and 751 /// declaration context. 752 virtual CallingConv getDefaultCallingConv(CallingConvMethodType MT) const { 753 // Not all targets will specify an explicit calling convention that we can 754 // express. This will always do the right thing, even though it's not 755 // an explicit calling convention. 756 return CC_C; 757 } 758 759 enum CallingConvCheckResult { 760 CCCR_OK, 761 CCCR_Warning 762 }; 763 764 /// \brief Determines whether a given calling convention is valid for the 765 /// target. A calling convention can either be accepted, produce a warning 766 /// and be substituted with the default calling convention, or (someday) 767 /// produce an error (such as using thiscall on a non-instance function). 768 virtual CallingConvCheckResult checkCallingConvention(CallingConv CC) const { 769 switch (CC) { 770 default: 771 return CCCR_Warning; 772 case CC_C: 773 case CC_Default: 774 return CCCR_OK; 775 } 776 } 777 778 protected: 779 virtual uint64_t getPointerWidthV(unsigned AddrSpace) const { 780 return PointerWidth; 781 } 782 virtual uint64_t getPointerAlignV(unsigned AddrSpace) const { 783 return PointerAlign; 784 } 785 virtual enum IntType getPtrDiffTypeV(unsigned AddrSpace) const { 786 return PtrDiffType; 787 } 788 virtual void getGCCRegNames(const char * const *&Names, 789 unsigned &NumNames) const = 0; 790 virtual void getGCCRegAliases(const GCCRegAlias *&Aliases, 791 unsigned &NumAliases) const = 0; 792 virtual void getGCCAddlRegNames(const AddlRegName *&Addl, 793 unsigned &NumAddl) const { 794 Addl = 0; 795 NumAddl = 0; 796 } 797 virtual bool validateAsmConstraint(const char *&Name, 798 TargetInfo::ConstraintInfo &info) const= 0; 799 }; 800 801 } // end namespace clang 802 803 #endif 804
