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//===--- TargetInfo.h - Expose information about the target -----*- C++ -*-===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
/// \file
/// Defines the clang::TargetInfo interface.
#include "clang/Basic/AddressSpaces.h"
#include "clang/Basic/LLVM.h"
#include "clang/Basic/Specifiers.h"
#include "clang/Basic/TargetCXXABI.h"
#include "clang/Basic/TargetOptions.h"
#include "llvm/ADT/APFloat.h"
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/IntrusiveRefCntPtr.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/VersionTuple.h"
#include <cassert>
#include <string>
#include <vector>
namespace llvm {
struct fltSemantics;
class DataLayout;
namespace clang {
class DiagnosticsEngine;
class LangOptions;
class CodeGenOptions;
class MacroBuilder;
class QualType;
class SourceLocation;
class SourceManager;
namespace Builtin { struct Info; }
/// Fields controlling how types are laid out in memory; these may need to
/// be copied for targets like AMDGPU that base their ABIs on an auxiliary
/// CPU target.
struct TransferrableTargetInfo {
unsigned char PointerWidth, PointerAlign;
unsigned char BoolWidth, BoolAlign;
unsigned char IntWidth, IntAlign;
unsigned char HalfWidth, HalfAlign;
unsigned char FloatWidth, FloatAlign;
unsigned char DoubleWidth, DoubleAlign;
unsigned char LongDoubleWidth, LongDoubleAlign, Float128Align;
unsigned char LargeArrayMinWidth, LargeArrayAlign;
unsigned char LongWidth, LongAlign;
unsigned char LongLongWidth, LongLongAlign;
// Fixed point bit widths
unsigned char ShortAccumWidth, ShortAccumAlign;
unsigned char AccumWidth, AccumAlign;
unsigned char LongAccumWidth, LongAccumAlign;
unsigned char ShortFractWidth, ShortFractAlign;
unsigned char FractWidth, FractAlign;
unsigned char LongFractWidth, LongFractAlign;
// If true, unsigned fixed point types have the same number of fractional bits
// as their signed counterparts, forcing the unsigned types to have one extra
// bit of padding. Otherwise, unsigned fixed point types have
// one more fractional bit than its corresponding signed type. This is false
// by default.
bool PaddingOnUnsignedFixedPoint;
// Fixed point integral and fractional bit sizes
// Saturated types share the same integral/fractional bits as their
// corresponding unsaturated types.
// For simplicity, the fractional bits in a _Fract type will be one less the
// width of that _Fract type. This leaves all signed _Fract types having no
// padding and unsigned _Fract types will only have 1 bit of padding after the
// sign if PaddingOnUnsignedFixedPoint is set.
unsigned char ShortAccumScale;
unsigned char AccumScale;
unsigned char LongAccumScale;
unsigned char SuitableAlign;
unsigned char DefaultAlignForAttributeAligned;
unsigned char MinGlobalAlign;
unsigned short NewAlign;
unsigned short MaxVectorAlign;
unsigned short MaxTLSAlign;
const llvm::fltSemantics *HalfFormat, *FloatFormat, *DoubleFormat,
*LongDoubleFormat, *Float128Format;
///===---- Target Data Type Query Methods -------------------------------===//
enum IntType {
NoInt = 0,
enum RealType {
NoFloat = 255,
Float = 0,
IntType SizeType, IntMaxType, PtrDiffType, IntPtrType, WCharType,
WIntType, Char16Type, Char32Type, Int64Type, SigAtomicType,
/// Whether Objective-C's built-in boolean type should be signed char.
/// Otherwise, when this flag is not set, the normal built-in boolean type is
/// used.
unsigned UseSignedCharForObjCBool : 1;
/// Control whether the alignment of bit-field types is respected when laying
/// out structures. If true, then the alignment of the bit-field type will be
/// used to (a) impact the alignment of the containing structure, and (b)
/// ensure that the individual bit-field will not straddle an alignment
/// boundary.
unsigned UseBitFieldTypeAlignment : 1;
/// Whether zero length bitfields (e.g., int : 0;) force alignment of
/// the next bitfield.
/// If the alignment of the zero length bitfield is greater than the member
/// that follows it, `bar', `bar' will be aligned as the type of the
/// zero-length bitfield.
unsigned UseZeroLengthBitfieldAlignment : 1;
/// Whether explicit bit field alignment attributes are honored.
unsigned UseExplicitBitFieldAlignment : 1;
/// If non-zero, specifies a fixed alignment value for bitfields that follow
/// zero length bitfield, regardless of the zero length bitfield type.
unsigned ZeroLengthBitfieldBoundary;
/// Exposes information about the current target.
class TargetInfo : public virtual TransferrableTargetInfo,
public RefCountedBase<TargetInfo> {
std::shared_ptr<TargetOptions> TargetOpts;
llvm::Triple Triple;
// Target values set by the ctor of the actual target implementation. Default
// values are specified by the TargetInfo constructor.
bool BigEndian;
bool TLSSupported;
bool VLASupported;
bool NoAsmVariants; // True if {|} are normal characters.
bool HasLegalHalfType; // True if the backend supports operations on the half
// LLVM IR type.
bool HasFloat128;
bool HasFloat16;
unsigned char MaxAtomicPromoteWidth, MaxAtomicInlineWidth;
unsigned short SimdDefaultAlign;
std::unique_ptr<llvm::DataLayout> DataLayout;
const char *MCountName;
unsigned char RegParmMax, SSERegParmMax;
const LangASMap *AddrSpaceMap;
mutable StringRef PlatformName;
mutable VersionTuple PlatformMinVersion;
unsigned HasAlignMac68kSupport : 1;
unsigned RealTypeUsesObjCFPRet : 3;
unsigned ComplexLongDoubleUsesFP2Ret : 1;
unsigned HasBuiltinMSVaList : 1;
unsigned IsRenderScriptTarget : 1;
unsigned HasAArch64SVETypes : 1;
// TargetInfo Constructor. Default initializes all fields.
TargetInfo(const llvm::Triple &T);
void resetDataLayout(StringRef DL);
/// Construct a target for the given options.
/// \param Opts - The options to use to initialize the target. The target may
/// modify the options to canonicalize the target feature information to match
/// what the backend expects.
static TargetInfo *
CreateTargetInfo(DiagnosticsEngine &Diags,
const std::shared_ptr<TargetOptions> &Opts);
virtual ~TargetInfo();
/// Retrieve the target options.
TargetOptions &getTargetOpts() const {
assert(TargetOpts && "Missing target options");
return *TargetOpts;
/// The different kinds of __builtin_va_list types defined by
/// the target implementation.
enum BuiltinVaListKind {
/// typedef char* __builtin_va_list;
CharPtrBuiltinVaList = 0,
/// typedef void* __builtin_va_list;
/// __builtin_va_list as defined by the AArch64 ABI
/// __builtin_va_list as defined by the PNaCl ABI:
/// __builtin_va_list as defined by the Power ABI:
/// /resources/downloads/Power-Arch-32-bit-ABI-supp-1.0-Embedded.pdf
/// __builtin_va_list as defined by the x86-64 ABI:
/// __builtin_va_list as defined by ARM AAPCS ABI
// /help/topic/com.arm.doc.ihi0042d/IHI0042D_aapcs.pdf
// typedef struct __va_list_tag
// {
// long __gpr;
// long __fpr;
// void *__overflow_arg_area;
// void *__reg_save_area;
// } va_list[1];
/// Specify if mangling based on address space map should be used or
/// not for language specific address spaces
bool UseAddrSpaceMapMangling;
IntType getSizeType() const { return SizeType; }
IntType getSignedSizeType() const {
switch (SizeType) {
case UnsignedShort:
return SignedShort;
case UnsignedInt:
return SignedInt;
case UnsignedLong:
return SignedLong;
case UnsignedLongLong:
return SignedLongLong;
llvm_unreachable("Invalid SizeType");
IntType getIntMaxType() const { return IntMaxType; }
IntType getUIntMaxType() const {
return getCorrespondingUnsignedType(IntMaxType);
IntType getPtrDiffType(unsigned AddrSpace) const {
return AddrSpace == 0 ? PtrDiffType : getPtrDiffTypeV(AddrSpace);
IntType getUnsignedPtrDiffType(unsigned AddrSpace) const {
return getCorrespondingUnsignedType(getPtrDiffType(AddrSpace));
IntType getIntPtrType() const { return IntPtrType; }
IntType getUIntPtrType() const {
return getCorrespondingUnsignedType(IntPtrType);
IntType getWCharType() const { return WCharType; }
IntType getWIntType() const { return WIntType; }
IntType getChar16Type() const { return Char16Type; }
IntType getChar32Type() const { return Char32Type; }
IntType getInt64Type() const { return Int64Type; }
IntType getUInt64Type() const {
return getCorrespondingUnsignedType(Int64Type);
IntType getSigAtomicType() const { return SigAtomicType; }
IntType getProcessIDType() const { return ProcessIDType; }
static IntType getCorrespondingUnsignedType(IntType T) {
switch (T) {
case SignedChar:
return UnsignedChar;
case SignedShort:
return UnsignedShort;
case SignedInt:
return UnsignedInt;
case SignedLong:
return UnsignedLong;
case SignedLongLong:
return UnsignedLongLong;
llvm_unreachable("Unexpected signed integer type");
/// In the event this target uses the same number of fractional bits for its
/// unsigned types as it does with its signed counterparts, there will be
/// exactly one bit of padding.
/// Return true if unsigned fixed point types have padding for this target.
bool doUnsignedFixedPointTypesHavePadding() const {
return PaddingOnUnsignedFixedPoint;
/// Return the width (in bits) of the specified integer type enum.
/// For example, SignedInt -> getIntWidth().
unsigned getTypeWidth(IntType T) const;
/// Return integer type with specified width.
virtual IntType getIntTypeByWidth(unsigned BitWidth, bool IsSigned) const;
/// Return the smallest integer type with at least the specified width.
virtual IntType getLeastIntTypeByWidth(unsigned BitWidth,
bool IsSigned) const;
/// Return floating point type with specified width.
RealType getRealTypeByWidth(unsigned BitWidth) const;
/// Return the alignment (in bits) of the specified integer type enum.
/// For example, SignedInt -> getIntAlign().
unsigned getTypeAlign(IntType T) const;
/// Returns true if the type is signed; false otherwise.
static bool isTypeSigned(IntType T);
/// Return the width of pointers on this target, for the
/// specified address space.
uint64_t getPointerWidth(unsigned AddrSpace) const {
return AddrSpace == 0 ? PointerWidth : getPointerWidthV(AddrSpace);
uint64_t getPointerAlign(unsigned AddrSpace) const {
return AddrSpace == 0 ? PointerAlign : getPointerAlignV(AddrSpace);
/// Return the maximum width of pointers on this target.
virtual uint64_t getMaxPointerWidth() const {
return PointerWidth;
/// Get integer value for null pointer.
/// \param AddrSpace address space of pointee in source language.
virtual uint64_t getNullPointerValue(LangAS AddrSpace) const { return 0; }
/// Return the size of '_Bool' and C++ 'bool' for this target, in bits.
unsigned getBoolWidth() const { return BoolWidth; }
/// Return the alignment of '_Bool' and C++ 'bool' for this target.
unsigned getBoolAlign() const { return BoolAlign; }
unsigned getCharWidth() const { return 8; } // FIXME
unsigned getCharAlign() const { return 8; } // FIXME
/// Return the size of 'signed short' and 'unsigned short' for this
/// target, in bits.
unsigned getShortWidth() const { return 16; } // FIXME
/// Return the alignment of 'signed short' and 'unsigned short' for
/// this target.
unsigned getShortAlign() const { return 16; } // FIXME
/// getIntWidth/Align - Return the size of 'signed int' and 'unsigned int' for
/// this target, in bits.
unsigned getIntWidth() const { return IntWidth; }
unsigned getIntAlign() const { return IntAlign; }
/// getLongWidth/Align - Return the size of 'signed long' and 'unsigned long'
/// for this target, in bits.
unsigned getLongWidth() const { return LongWidth; }
unsigned getLongAlign() const { return LongAlign; }
/// getLongLongWidth/Align - Return the size of 'signed long long' and
/// 'unsigned long long' for this target, in bits.
unsigned getLongLongWidth() const { return LongLongWidth; }
unsigned getLongLongAlign() const { return LongLongAlign; }
/// getShortAccumWidth/Align - Return the size of 'signed short _Accum' and
/// 'unsigned short _Accum' for this target, in bits.
unsigned getShortAccumWidth() const { return ShortAccumWidth; }
unsigned getShortAccumAlign() const { return ShortAccumAlign; }
/// getAccumWidth/Align - Return the size of 'signed _Accum' and
/// 'unsigned _Accum' for this target, in bits.
unsigned getAccumWidth() const { return AccumWidth; }
unsigned getAccumAlign() const { return AccumAlign; }
/// getLongAccumWidth/Align - Return the size of 'signed long _Accum' and
/// 'unsigned long _Accum' for this target, in bits.
unsigned getLongAccumWidth() const { return LongAccumWidth; }
unsigned getLongAccumAlign() const { return LongAccumAlign; }
/// getShortFractWidth/Align - Return the size of 'signed short _Fract' and
/// 'unsigned short _Fract' for this target, in bits.
unsigned getShortFractWidth() const { return ShortFractWidth; }
unsigned getShortFractAlign() const { return ShortFractAlign; }
/// getFractWidth/Align - Return the size of 'signed _Fract' and
/// 'unsigned _Fract' for this target, in bits.
unsigned getFractWidth() const { return FractWidth; }
unsigned getFractAlign() const { return FractAlign; }
/// getLongFractWidth/Align - Return the size of 'signed long _Fract' and
/// 'unsigned long _Fract' for this target, in bits.
unsigned getLongFractWidth() const { return LongFractWidth; }
unsigned getLongFractAlign() const { return LongFractAlign; }
/// getShortAccumScale/IBits - Return the number of fractional/integral bits
/// in a 'signed short _Accum' type.
unsigned getShortAccumScale() const { return ShortAccumScale; }
unsigned getShortAccumIBits() const {
return ShortAccumWidth - ShortAccumScale - 1;
/// getAccumScale/IBits - Return the number of fractional/integral bits
/// in a 'signed _Accum' type.
unsigned getAccumScale() const { return AccumScale; }
unsigned getAccumIBits() const { return AccumWidth - AccumScale - 1; }
/// getLongAccumScale/IBits - Return the number of fractional/integral bits
/// in a 'signed long _Accum' type.
unsigned getLongAccumScale() const { return LongAccumScale; }
unsigned getLongAccumIBits() const {
return LongAccumWidth - LongAccumScale - 1;
/// getUnsignedShortAccumScale/IBits - Return the number of
/// fractional/integral bits in a 'unsigned short _Accum' type.
unsigned getUnsignedShortAccumScale() const {
return PaddingOnUnsignedFixedPoint ? ShortAccumScale : ShortAccumScale + 1;
unsigned getUnsignedShortAccumIBits() const {
return PaddingOnUnsignedFixedPoint
? getShortAccumIBits()
: ShortAccumWidth - getUnsignedShortAccumScale();
/// getUnsignedAccumScale/IBits - Return the number of fractional/integral
/// bits in a 'unsigned _Accum' type.
unsigned getUnsignedAccumScale() const {
return PaddingOnUnsignedFixedPoint ? AccumScale : AccumScale + 1;
unsigned getUnsignedAccumIBits() const {
return PaddingOnUnsignedFixedPoint ? getAccumIBits()
: AccumWidth - getUnsignedAccumScale();
/// getUnsignedLongAccumScale/IBits - Return the number of fractional/integral
/// bits in a 'unsigned long _Accum' type.
unsigned getUnsignedLongAccumScale() const {
return PaddingOnUnsignedFixedPoint ? LongAccumScale : LongAccumScale + 1;
unsigned getUnsignedLongAccumIBits() const {
return PaddingOnUnsignedFixedPoint
? getLongAccumIBits()
: LongAccumWidth - getUnsignedLongAccumScale();
/// getShortFractScale - Return the number of fractional bits
/// in a 'signed short _Fract' type.
unsigned getShortFractScale() const { return ShortFractWidth - 1; }
/// getFractScale - Return the number of fractional bits
/// in a 'signed _Fract' type.
unsigned getFractScale() const { return FractWidth - 1; }
/// getLongFractScale - Return the number of fractional bits
/// in a 'signed long _Fract' type.
unsigned getLongFractScale() const { return LongFractWidth - 1; }
/// getUnsignedShortFractScale - Return the number of fractional bits
/// in a 'unsigned short _Fract' type.
unsigned getUnsignedShortFractScale() const {
return PaddingOnUnsignedFixedPoint ? getShortFractScale()
: getShortFractScale() + 1;
/// getUnsignedFractScale - Return the number of fractional bits
/// in a 'unsigned _Fract' type.
unsigned getUnsignedFractScale() const {
return PaddingOnUnsignedFixedPoint ? getFractScale() : getFractScale() + 1;
/// getUnsignedLongFractScale - Return the number of fractional bits
/// in a 'unsigned long _Fract' type.
unsigned getUnsignedLongFractScale() const {
return PaddingOnUnsignedFixedPoint ? getLongFractScale()
: getLongFractScale() + 1;
/// Determine whether the __int128 type is supported on this target.
virtual bool hasInt128Type() const {
return (getPointerWidth(0) >= 64) || getTargetOpts().ForceEnableInt128;
} // FIXME
/// Determine whether _Float16 is supported on this target.
virtual bool hasLegalHalfType() const { return HasLegalHalfType; }
/// Determine whether the __float128 type is supported on this target.
virtual bool hasFloat128Type() const { return HasFloat128; }
/// Determine whether the _Float16 type is supported on this target.
virtual bool hasFloat16Type() const { return HasFloat16; }
/// Return the alignment that is suitable for storing any
/// object with a fundamental alignment requirement.
unsigned getSuitableAlign() const { return SuitableAlign; }
/// Return the default alignment for __attribute__((aligned)) on
/// this target, to be used if no alignment value is specified.
unsigned getDefaultAlignForAttributeAligned() const {
return DefaultAlignForAttributeAligned;
/// getMinGlobalAlign - Return the minimum alignment of a global variable,
/// unless its alignment is explicitly reduced via attributes.
virtual unsigned getMinGlobalAlign (uint64_t) const {
return MinGlobalAlign;
/// Return the largest alignment for which a suitably-sized allocation with
/// '::operator new(size_t)' is guaranteed to produce a correctly-aligned
/// pointer.
unsigned getNewAlign() const {
return NewAlign ? NewAlign : std::max(LongDoubleAlign, LongLongAlign);
/// getWCharWidth/Align - Return the size of 'wchar_t' for this target, in
/// bits.
unsigned getWCharWidth() const { return getTypeWidth(WCharType); }
unsigned getWCharAlign() const { return getTypeAlign(WCharType); }
/// getChar16Width/Align - Return the size of 'char16_t' for this target, in
/// bits.
unsigned getChar16Width() const { return getTypeWidth(Char16Type); }
unsigned getChar16Align() const { return getTypeAlign(Char16Type); }
/// getChar32Width/Align - Return the size of 'char32_t' for this target, in
/// bits.
unsigned getChar32Width() const { return getTypeWidth(Char32Type); }
unsigned getChar32Align() const { return getTypeAlign(Char32Type); }
/// getHalfWidth/Align/Format - Return the size/align/format of 'half'.
unsigned getHalfWidth() const { return HalfWidth; }
unsigned getHalfAlign() const { return HalfAlign; }
const llvm::fltSemantics &getHalfFormat() const { return *HalfFormat; }
/// getFloatWidth/Align/Format - Return the size/align/format of 'float'.
unsigned getFloatWidth() const { return FloatWidth; }
unsigned getFloatAlign() const { return FloatAlign; }
const llvm::fltSemantics &getFloatFormat() const { return *FloatFormat; }
/// getDoubleWidth/Align/Format - Return the size/align/format of 'double'.
unsigned getDoubleWidth() const { return DoubleWidth; }
unsigned getDoubleAlign() const { return DoubleAlign; }
const llvm::fltSemantics &getDoubleFormat() const { return *DoubleFormat; }
/// getLongDoubleWidth/Align/Format - Return the size/align/format of 'long
/// double'.
unsigned getLongDoubleWidth() const { return LongDoubleWidth; }
unsigned getLongDoubleAlign() const { return LongDoubleAlign; }
const llvm::fltSemantics &getLongDoubleFormat() const {
return *LongDoubleFormat;
/// getFloat128Width/Align/Format - Return the size/align/format of
/// '__float128'.
unsigned getFloat128Width() const { return 128; }
unsigned getFloat128Align() const { return Float128Align; }
const llvm::fltSemantics &getFloat128Format() const {
return *Float128Format;
/// Return the mangled code of long double.
virtual const char *getLongDoubleMangling() const { return "e"; }
/// Return the mangled code of __float128.
virtual const char *getFloat128Mangling() const { return "g"; }
/// Return the value for the C99 FLT_EVAL_METHOD macro.
virtual unsigned getFloatEvalMethod() const { return 0; }
// getLargeArrayMinWidth/Align - Return the minimum array size that is
// 'large' and its alignment.
unsigned getLargeArrayMinWidth() const { return LargeArrayMinWidth; }
unsigned getLargeArrayAlign() const { return LargeArrayAlign; }
/// Return the maximum width lock-free atomic operation which will
/// ever be supported for the given target
unsigned getMaxAtomicPromoteWidth() const { return MaxAtomicPromoteWidth; }
/// Return the maximum width lock-free atomic operation which can be
/// inlined given the supported features of the given target.
unsigned getMaxAtomicInlineWidth() const { return MaxAtomicInlineWidth; }
/// Set the maximum inline or promote width lock-free atomic operation
/// for the given target.
virtual void setMaxAtomicWidth() {}
/// Returns true if the given target supports lock-free atomic
/// operations at the specified width and alignment.
virtual bool hasBuiltinAtomic(uint64_t AtomicSizeInBits,
uint64_t AlignmentInBits) const {
return AtomicSizeInBits <= AlignmentInBits &&
AtomicSizeInBits <= getMaxAtomicInlineWidth() &&
(AtomicSizeInBits <= getCharWidth() ||
llvm::isPowerOf2_64(AtomicSizeInBits / getCharWidth()));
/// Return the maximum vector alignment supported for the given target.
unsigned getMaxVectorAlign() const { return MaxVectorAlign; }
/// Return default simd alignment for the given target. Generally, this
/// value is type-specific, but this alignment can be used for most of the
/// types for the given target.
unsigned getSimdDefaultAlign() const { return SimdDefaultAlign; }
/// Return the alignment (in bits) of the thrown exception object. This is
/// only meaningful for targets that allocate C++ exceptions in a system
/// runtime, such as those using the Itanium C++ ABI.
virtual unsigned getExnObjectAlignment() const {
// Itanium says that an _Unwind_Exception has to be "double-word"
// aligned (and thus the end of it is also so-aligned), meaning 16
// bytes. Of course, that was written for the actual Itanium,
// which is a 64-bit platform. Classically, the ABI doesn't really
// specify the alignment on other platforms, but in practice
// libUnwind declares the struct with __attribute__((aligned)), so
// we assume that alignment here. (It's generally 16 bytes, but
// some targets overwrite it.)
return getDefaultAlignForAttributeAligned();
/// Return the size of intmax_t and uintmax_t for this target, in bits.
unsigned getIntMaxTWidth() const {
return getTypeWidth(IntMaxType);
// Return the size of unwind_word for this target.
virtual unsigned getUnwindWordWidth() const { return getPointerWidth(0); }
/// Return the "preferred" register width on this target.
virtual unsigned getRegisterWidth() const {
// Currently we assume the register width on the target matches the pointer
// width, we can introduce a new variable for this if/when some target wants
// it.
return PointerWidth;
/// Returns the name of the mcount instrumentation function.
const char *getMCountName() const {
return MCountName;
/// Check if the Objective-C built-in boolean type should be signed
/// char.
/// Otherwise, if this returns false, the normal built-in boolean type
/// should also be used for Objective-C.
bool useSignedCharForObjCBool() const {
return UseSignedCharForObjCBool;
void noSignedCharForObjCBool() {
UseSignedCharForObjCBool = false;
/// Check whether the alignment of bit-field types is respected
/// when laying out structures.
bool useBitFieldTypeAlignment() const {
return UseBitFieldTypeAlignment;
/// Check whether zero length bitfields should force alignment of
/// the next member.
bool useZeroLengthBitfieldAlignment() const {
return UseZeroLengthBitfieldAlignment;
/// Get the fixed alignment value in bits for a member that follows
/// a zero length bitfield.
unsigned getZeroLengthBitfieldBoundary() const {
return ZeroLengthBitfieldBoundary;
/// Check whether explicit bitfield alignment attributes should be
// honored, as in "__attribute__((aligned(2))) int b : 1;".
bool useExplicitBitFieldAlignment() const {
return UseExplicitBitFieldAlignment;
/// Check whether this target support '\#pragma options align=mac68k'.
bool hasAlignMac68kSupport() const {
return HasAlignMac68kSupport;
/// Return the user string for the specified integer type enum.
/// For example, SignedShort -> "short".
static const char *getTypeName(IntType T);
/// Return the constant suffix for the specified integer type enum.
/// For example, SignedLong -> "L".
const char *getTypeConstantSuffix(IntType T) const;
/// Return the printf format modifier for the specified
/// integer type enum.
/// For example, SignedLong -> "l".
static const char *getTypeFormatModifier(IntType T);
/// Check whether the given real type should use the "fpret" flavor of
/// Objective-C message passing on this target.
bool useObjCFPRetForRealType(RealType T) const {
return RealTypeUsesObjCFPRet & (1 << T);
/// Check whether _Complex long double should use the "fp2ret" flavor
/// of Objective-C message passing on this target.
bool useObjCFP2RetForComplexLongDouble() const {
return ComplexLongDoubleUsesFP2Ret;
/// Check whether llvm intrinsics such as should be used
/// to convert to and from __fp16.
/// FIXME: This function should be removed once all targets stop using the
/// conversion intrinsics.
virtual bool useFP16ConversionIntrinsics() const {
return true;
/// Specify if mangling based on address space map should be used or
/// not for language specific address spaces
bool useAddressSpaceMapMangling() const {
return UseAddrSpaceMapMangling;
///===---- Other target property query methods --------------------------===//
/// Appends the target-specific \#define values for this
/// target set to the specified buffer.
virtual void getTargetDefines(const LangOptions &Opts,
MacroBuilder &Builder) const = 0;
/// Return information about target-specific builtins for
/// the current primary target, and info about which builtins are non-portable
/// across the current set of primary and secondary targets.
virtual ArrayRef<Builtin::Info> getTargetBuiltins() const = 0;
/// The __builtin_clz* and __builtin_ctz* built-in
/// functions are specified to have undefined results for zero inputs, but
/// on targets that support these operations in a way that provides
/// well-defined results for zero without loss of performance, it is a good
/// idea to avoid optimizing based on that undef behavior.
virtual bool isCLZForZeroUndef() const { return true; }
/// Returns the kind of __builtin_va_list type that should be used
/// with this target.
virtual BuiltinVaListKind getBuiltinVaListKind() const = 0;
/// Returns whether or not type \c __builtin_ms_va_list type is
/// available on this target.
bool hasBuiltinMSVaList() const { return HasBuiltinMSVaList; }
/// Returns true for RenderScript.
bool isRenderScriptTarget() const { return IsRenderScriptTarget; }
/// Returns whether or not the AArch64 SVE built-in types are
/// available on this target.
bool hasAArch64SVETypes() const { return HasAArch64SVETypes; }
/// Returns whether the passed in string is a valid clobber in an
/// inline asm statement.
/// This is used by Sema.
bool isValidClobber(StringRef Name) const;
/// Returns whether the passed in string is a valid register name
/// according to GCC.
/// This is used by Sema for inline asm statements.
virtual bool isValidGCCRegisterName(StringRef Name) const;
/// Returns the "normalized" GCC register name.
/// ReturnCannonical true will return the register name without any additions
/// such as "{}" or "%" in it's canonical form, for example:
/// ReturnCanonical = true and Name = "rax", will return "ax".
StringRef getNormalizedGCCRegisterName(StringRef Name,
bool ReturnCanonical = false) const;
/// Extracts a register from the passed constraint (if it is a
/// single-register constraint) and the asm label expression related to a
/// variable in the input or output list of an inline asm statement.
/// This function is used by Sema in order to diagnose conflicts between
/// the clobber list and the input/output lists.
virtual StringRef getConstraintRegister(StringRef Constraint,
StringRef Expression) const {
return "";
struct ConstraintInfo {
enum {
CI_None = 0x00,
CI_AllowsMemory = 0x01,
CI_AllowsRegister = 0x02,
CI_ReadWrite = 0x04, // "+r" output constraint (read and write).
CI_HasMatchingInput = 0x08, // This output operand has a matching input.
CI_ImmediateConstant = 0x10, // This operand must be an immediate constant
CI_EarlyClobber = 0x20, // "&" output constraint (early clobber).
unsigned Flags;
int TiedOperand;
struct {
int Min;
int Max;
bool isConstrained;
} ImmRange;
llvm::SmallSet<int, 4> ImmSet;
std::string ConstraintStr; // constraint: "=rm"
std::string Name; // Operand name: [foo] with no []'s.
ConstraintInfo(StringRef ConstraintStr, StringRef Name)
: Flags(0), TiedOperand(-1), ConstraintStr(ConstraintStr.str()),
Name(Name.str()) {
ImmRange.Min = ImmRange.Max = 0;
ImmRange.isConstrained = false;
const std::string &getConstraintStr() const { return ConstraintStr; }
const std::string &getName() const { return Name; }
bool isReadWrite() const { return (Flags & CI_ReadWrite) != 0; }
bool earlyClobber() { return (Flags & CI_EarlyClobber) != 0; }
bool allowsRegister() const { return (Flags & CI_AllowsRegister) != 0; }
bool allowsMemory() const { return (Flags & CI_AllowsMemory) != 0; }
/// Return true if this output operand has a matching
/// (tied) input operand.
bool hasMatchingInput() const { return (Flags & CI_HasMatchingInput) != 0; }
/// Return true if this input operand is a matching
/// constraint that ties it to an output operand.
/// If this returns true then getTiedOperand will indicate which output
/// operand this is tied to.
bool hasTiedOperand() const { return TiedOperand != -1; }
unsigned getTiedOperand() const {
assert(hasTiedOperand() && "Has no tied operand!");
return (unsigned)TiedOperand;
bool requiresImmediateConstant() const {
return (Flags & CI_ImmediateConstant) != 0;
bool isValidAsmImmediate(const llvm::APInt &Value) const {
if (!ImmSet.empty())
return Value.isSignedIntN(32) &&
ImmSet.count(Value.getZExtValue()) != 0;
return !ImmRange.isConstrained ||
(Value.sge(ImmRange.Min) && Value.sle(ImmRange.Max));
void setIsReadWrite() { Flags |= CI_ReadWrite; }
void setEarlyClobber() { Flags |= CI_EarlyClobber; }
void setAllowsMemory() { Flags |= CI_AllowsMemory; }
void setAllowsRegister() { Flags |= CI_AllowsRegister; }
void setHasMatchingInput() { Flags |= CI_HasMatchingInput; }
void setRequiresImmediate(int Min, int Max) {
Flags |= CI_ImmediateConstant;
ImmRange.Min = Min;
ImmRange.Max = Max;
ImmRange.isConstrained = true;
void setRequiresImmediate(llvm::ArrayRef<int> Exacts) {
Flags |= CI_ImmediateConstant;
for (int Exact : Exacts)
void setRequiresImmediate(int Exact) {
Flags |= CI_ImmediateConstant;
void setRequiresImmediate() {
Flags |= CI_ImmediateConstant;
/// Indicate that this is an input operand that is tied to
/// the specified output operand.
/// Copy over the various constraint information from the output.
void setTiedOperand(unsigned N, ConstraintInfo &Output) {
Flags = Output.Flags;
TiedOperand = N;
// Don't copy Name or constraint string.
/// Validate register name used for global register variables.
/// This function returns true if the register passed in RegName can be used
/// for global register variables on this target. In addition, it returns
/// true in HasSizeMismatch if the size of the register doesn't match the
/// variable size passed in RegSize.
virtual bool validateGlobalRegisterVariable(StringRef RegName,
unsigned RegSize,
bool &HasSizeMismatch) const {
HasSizeMismatch = false;
return true;
// validateOutputConstraint, validateInputConstraint - Checks that
// a constraint is valid and provides information about it.
// FIXME: These should return a real error instead of just true/false.
bool validateOutputConstraint(ConstraintInfo &Info) const;
bool validateInputConstraint(MutableArrayRef<ConstraintInfo> OutputConstraints,
ConstraintInfo &info) const;
virtual bool validateOutputSize(StringRef /*Constraint*/,
unsigned /*Size*/) const {
return true;
virtual bool validateInputSize(StringRef /*Constraint*/,
unsigned /*Size*/) const {
return true;
virtual bool
validateConstraintModifier(StringRef /*Constraint*/,
char /*Modifier*/,
unsigned /*Size*/,
std::string &/*SuggestedModifier*/) const {
return true;
virtual bool
validateAsmConstraint(const char *&Name,
TargetInfo::ConstraintInfo &info) const = 0;
bool resolveSymbolicName(const char *&Name,
ArrayRef<ConstraintInfo> OutputConstraints,
unsigned &Index) const;
// Constraint parm will be left pointing at the last character of
// the constraint. In practice, it won't be changed unless the
// constraint is longer than one character.
virtual std::string convertConstraint(const char *&Constraint) const {
// 'p' defaults to 'r', but can be overridden by targets.
if (*Constraint == 'p')
return std::string("r");
return std::string(1, *Constraint);
/// Returns a string of target-specific clobbers, in LLVM format.
virtual const char *getClobbers() const = 0;
/// Returns true if NaN encoding is IEEE 754-2008.
/// Only MIPS allows a different encoding.
virtual bool isNan2008() const {
return true;
/// Returns the target triple of the primary target.
const llvm::Triple &getTriple() const {
return Triple;
const llvm::DataLayout &getDataLayout() const {
assert(DataLayout && "Uninitialized DataLayout!");
return *DataLayout;
struct GCCRegAlias {
const char * const Aliases[5];
const char * const Register;
struct AddlRegName {
const char * const Names[5];
const unsigned RegNum;
/// Does this target support "protected" visibility?
/// Any target which dynamic libraries will naturally support
/// something like "default" (meaning that the symbol is visible
/// outside this shared object) and "hidden" (meaning that it isn't)
/// visibilities, but "protected" is really an ELF-specific concept
/// with weird semantics designed around the convenience of dynamic
/// linker implementations. Which is not to suggest that there's
/// consistent target-independent semantics for "default" visibility
/// either; the entire thing is pretty badly mangled.
virtual bool hasProtectedVisibility() const { return true; }
/// An optional hook that targets can implement to perform semantic
/// checking on attribute((section("foo"))) specifiers.
/// In this case, "foo" is passed in to be checked. If the section
/// specifier is invalid, the backend should return a non-empty string
/// that indicates the problem.
/// This hook is a simple quality of implementation feature to catch errors
/// and give good diagnostics in cases when the assembler or code generator
/// would otherwise reject the section specifier.
virtual std::string isValidSectionSpecifier(StringRef SR) const {
return "";
/// Set forced language options.
/// Apply changes to the target information with respect to certain
/// language options which change the target configuration and adjust
/// the language based on the target options where applicable.
virtual void adjust(LangOptions &Opts);
/// Adjust target options based on codegen options.
virtual void adjustTargetOptions(const CodeGenOptions &CGOpts,
TargetOptions &TargetOpts) const {}
/// Initialize the map with the default set of target features for the
/// CPU this should include all legal feature strings on the target.
/// \return False on error (invalid features).
virtual bool initFeatureMap(llvm::StringMap<bool> &Features,
DiagnosticsEngine &Diags, StringRef CPU,
const std::vector<std::string> &FeatureVec) const;
/// Get the ABI currently in use.
virtual StringRef getABI() const { return StringRef(); }
/// Get the C++ ABI currently in use.
TargetCXXABI getCXXABI() const {
return TheCXXABI;
/// Target the specified CPU.
/// \return False on error (invalid CPU name).
virtual bool setCPU(const std::string &Name) {
return false;
/// Fill a SmallVectorImpl with the valid values to setCPU.
virtual void fillValidCPUList(SmallVectorImpl<StringRef> &Values) const {}
/// brief Determine whether this TargetInfo supports the given CPU name.
virtual bool isValidCPUName(StringRef Name) const {
return true;
/// Use the specified ABI.
/// \return False on error (invalid ABI name).
virtual bool setABI(const std::string &Name) {
return false;
/// Use the specified unit for FP math.
/// \return False on error (invalid unit name).
virtual bool setFPMath(StringRef Name) {
return false;
/// Enable or disable a specific target feature;
/// the feature name must be valid.
virtual void setFeatureEnabled(llvm::StringMap<bool> &Features,
StringRef Name,
bool Enabled) const {
Features[Name] = Enabled;
/// Determine whether this TargetInfo supports the given feature.
virtual bool isValidFeatureName(StringRef Feature) const {
return true;
/// Perform initialization based on the user configured
/// set of features (e.g., +sse4).
/// The list is guaranteed to have at most one entry per feature.
/// The target may modify the features list, to change which options are
/// passed onwards to the backend.
/// FIXME: This part should be fixed so that we can change handleTargetFeatures
/// to merely a TargetInfo initialization routine.
/// \return False on error.
virtual bool handleTargetFeatures(std::vector<std::string> &Features,
DiagnosticsEngine &Diags) {
return true;
/// Determine whether the given target has the given feature.
virtual bool hasFeature(StringRef Feature) const {
return false;
/// Identify whether this target supports multiversioning of functions,
/// which requires support for cpu_supports and cpu_is functionality.
bool supportsMultiVersioning() const {
return getTriple().getArch() == llvm::Triple::x86 ||
getTriple().getArch() == llvm::Triple::x86_64;
/// Identify whether this target supports IFuncs.
bool supportsIFunc() const { return getTriple().isOSBinFormatELF(); }
// Validate the contents of the __builtin_cpu_supports(const char*)
// argument.
virtual bool validateCpuSupports(StringRef Name) const { return false; }
// Return the target-specific priority for features/cpus/vendors so
// that they can be properly sorted for checking.
virtual unsigned multiVersionSortPriority(StringRef Name) const {
return 0;
// Validate the contents of the __builtin_cpu_is(const char*)
// argument.
virtual bool validateCpuIs(StringRef Name) const { return false; }
// Validate a cpu_dispatch/cpu_specific CPU option, which is a different list
// from cpu_is, since it checks via features rather than CPUs directly.
virtual bool validateCPUSpecificCPUDispatch(StringRef Name) const {
return false;
// Get the character to be added for mangling purposes for cpu_specific.
virtual char CPUSpecificManglingCharacter(StringRef Name) const {
"cpu_specific Multiversioning not implemented on this target");
// Get a list of the features that make up the CPU option for
// cpu_specific/cpu_dispatch so that it can be passed to llvm as optimization
// options.
virtual void getCPUSpecificCPUDispatchFeatures(
StringRef Name, llvm::SmallVectorImpl<StringRef> &Features) const {
"cpu_specific Multiversioning not implemented on this target");
// Returns maximal number of args passed in registers.
unsigned getRegParmMax() const {
assert(RegParmMax < 7 && "RegParmMax value is larger than AST can handle");
return RegParmMax;
/// Whether the target supports thread-local storage.
bool isTLSSupported() const {
return TLSSupported;
/// Return the maximum alignment (in bits) of a TLS variable
/// Gets the maximum alignment (in bits) of a TLS variable on this target.
/// Returns zero if there is no such constraint.
unsigned short getMaxTLSAlign() const {
return MaxTLSAlign;
/// Whether target supports variable-length arrays.
bool isVLASupported() const { return VLASupported; }
/// Whether the target supports SEH __try.
bool isSEHTrySupported() const {
return getTriple().isOSWindows() &&
(getTriple().getArch() == llvm::Triple::x86 ||
getTriple().getArch() == llvm::Triple::x86_64 ||
getTriple().getArch() == llvm::Triple::aarch64);
/// Return true if {|} are normal characters in the asm string.
/// If this returns false (the default), then {abc|xyz} is syntax
/// that says that when compiling for asm variant #0, "abc" should be
/// generated, but when compiling for asm variant #1, "xyz" should be
/// generated.
bool hasNoAsmVariants() const {
return NoAsmVariants;
/// Return the register number that __builtin_eh_return_regno would
/// return with the specified argument.
/// This corresponds with TargetLowering's getExceptionPointerRegister
/// and getExceptionSelectorRegister in the backend.
virtual int getEHDataRegisterNumber(unsigned RegNo) const {
return -1;
/// Return the section to use for C++ static initialization functions.
virtual const char *getStaticInitSectionSpecifier() const {
return nullptr;
const LangASMap &getAddressSpaceMap() const { return *AddrSpaceMap; }
/// Map from the address space field in builtin description strings to the
/// language address space.
virtual LangAS getOpenCLBuiltinAddressSpace(unsigned AS) const {
return getLangASFromTargetAS(AS);
/// Map from the address space field in builtin description strings to the
/// language address space.
virtual LangAS getCUDABuiltinAddressSpace(unsigned AS) const {
return getLangASFromTargetAS(AS);
/// Return an AST address space which can be used opportunistically
/// for constant global memory. It must be possible to convert pointers into
/// this address space to LangAS::Default. If no such address space exists,
/// this may return None, and such optimizations will be disabled.
virtual llvm::Optional<LangAS> getConstantAddressSpace() const {
return LangAS::Default;
/// Retrieve the name of the platform as it is used in the
/// availability attribute.
StringRef getPlatformName() const { return PlatformName; }
/// Retrieve the minimum desired version of the platform, to
/// which the program should be compiled.
VersionTuple getPlatformMinVersion() const { return PlatformMinVersion; }
bool isBigEndian() const { return BigEndian; }
bool isLittleEndian() const { return !BigEndian; }
/// Gets the default calling convention for the given target and
/// declaration context.
virtual CallingConv getDefaultCallingConv() const {
// Not all targets will specify an explicit calling convention that we can
// express. This will always do the right thing, even though it's not
// an explicit calling convention.
return CC_C;
enum CallingConvCheckResult {
/// Determines whether a given calling convention is valid for the
/// target. A calling convention can either be accepted, produce a warning
/// and be substituted with the default calling convention, or (someday)
/// produce an error (such as using thiscall on a non-instance function).
virtual CallingConvCheckResult checkCallingConvention(CallingConv CC) const {
switch (CC) {
return CCCR_Warning;
case CC_C:
return CCCR_OK;
enum CallingConvKind {
virtual CallingConvKind getCallingConvKind(bool ClangABICompat4) const;
/// Controls if __builtin_longjmp / __builtin_setjmp can be lowered to
/// /
virtual bool hasSjLjLowering() const {
return false;
/// Check if the target supports CFProtection branch.
virtual bool
checkCFProtectionBranchSupported(DiagnosticsEngine &Diags) const;
/// Check if the target supports CFProtection branch.
virtual bool
checkCFProtectionReturnSupported(DiagnosticsEngine &Diags) const;
/// Whether target allows to overalign ABI-specified preferred alignment
virtual bool allowsLargerPreferedTypeAlignment() const { return true; }
/// Set supported OpenCL extensions and optional core features.
virtual void setSupportedOpenCLOpts() {}
/// Set supported OpenCL extensions as written on command line
virtual void setOpenCLExtensionOpts() {
for (const auto &Ext : getTargetOpts().OpenCLExtensionsAsWritten) {
/// Get supported OpenCL extensions and optional core features.
OpenCLOptions &getSupportedOpenCLOpts() {
return getTargetOpts().SupportedOpenCLOptions;
/// Get const supported OpenCL extensions and optional core features.
const OpenCLOptions &getSupportedOpenCLOpts() const {
return getTargetOpts().SupportedOpenCLOptions;
enum OpenCLTypeKind {
/// Get address space for OpenCL type.
virtual LangAS getOpenCLTypeAddrSpace(OpenCLTypeKind TK) const;
/// \returns Target specific vtbl ptr address space.
virtual unsigned getVtblPtrAddressSpace() const {
return 0;
/// \returns If a target requires an address within a target specific address
/// space \p AddressSpace to be converted in order to be used, then return the
/// corresponding target specific DWARF address space.
/// \returns Otherwise return None and no conversion will be emitted in the
/// DWARF.
virtual Optional<unsigned> getDWARFAddressSpace(unsigned AddressSpace) const {
return None;
/// \returns The version of the SDK which was used during the compilation if
/// one was specified, or an empty version otherwise.
const llvm::VersionTuple &getSDKVersion() const {
return getTargetOpts().SDKVersion;
/// Check the target is valid after it is fully initialized.
virtual bool validateTarget(DiagnosticsEngine &Diags) const {
return true;
virtual void setAuxTarget(const TargetInfo *Aux) {}
/// Copy type and layout related info.
void copyAuxTarget(const TargetInfo *Aux);
virtual uint64_t getPointerWidthV(unsigned AddrSpace) const {
return PointerWidth;
virtual uint64_t getPointerAlignV(unsigned AddrSpace) const {
return PointerAlign;
virtual enum IntType getPtrDiffTypeV(unsigned AddrSpace) const {
return PtrDiffType;
virtual ArrayRef<const char *> getGCCRegNames() const = 0;
virtual ArrayRef<GCCRegAlias> getGCCRegAliases() const = 0;
virtual ArrayRef<AddlRegName> getGCCAddlRegNames() const {
return None;
// Assert the values for the fractional and integral bits for each fixed point
// type follow the restrictions given in clause of N1169.
void CheckFixedPointBits() const;
} // end namespace clang