LLVM  3.7.0
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llvm::APFloat Class Reference

A self-contained host- and target-independent arbitrary-precision floating-point software implementation. More...

#include <APFloat.h>

Collaboration diagram for llvm::APFloat:
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Public Types

enum  cmpResult { cmpLessThan, cmpEqual, cmpGreaterThan, cmpUnordered }
 IEEE-754R 5.11: Floating Point Comparison Relations. More...
 
enum  roundingMode {
  rmNearestTiesToEven, rmTowardPositive, rmTowardNegative, rmTowardZero,
  rmNearestTiesToAway
}
 IEEE-754R 4.3: Rounding-direction attributes. More...
 
enum  opStatus {
  opOK = 0x00, opInvalidOp = 0x01, opDivByZero = 0x02, opOverflow = 0x04,
  opUnderflow = 0x08, opInexact = 0x10
}
 IEEE-754R 7: Default exception handling. More...
 
enum  fltCategory { fcInfinity, fcNaN, fcNormal, fcZero }
 Category of internally-represented number. More...
 
enum  uninitializedTag { uninitialized }
 Convenience enum used to construct an uninitialized APFloat. More...
 
enum  IlogbErrorKinds { IEK_Zero = INT_MIN+1, IEK_NaN = INT_MIN, IEK_Inf = INT_MAX }
 Enumeration of ilogb error results. More...
 
typedef signed short ExponentType
 A signed type to represent a floating point numbers unbiased exponent. More...
 

Public Member Functions

bool needsCleanup () const
 Returns whether this instance allocated memory. More...
 
void Profile (FoldingSetNodeID &NID) const
 Used to insert APFloat objects, or objects that contain APFloat objects, into FoldingSets. More...
 
bool operator== (const APFloat &) const =delete
 The definition of equality is not straightforward for floating point, so we won't use operator==. More...
 
cmpResult compare (const APFloat &) const
 IEEE comparison with another floating point number (NaNs compare unordered, 0==-0). More...
 
bool bitwiseIsEqual (const APFloat &) const
 Bitwise comparison for equality (QNaNs compare equal, 0!=-0). More...
 
unsigned int convertToHexString (char *dst, unsigned int hexDigits, bool upperCase, roundingMode) const
 Write out a hexadecimal representation of the floating point value to DST, which must be of sufficient size, in the C99 form [-]0xh.hhhhp[+-]d. More...
 
APFloatoperator= (const APFloat &)
 
APFloatoperator= (APFloat &&)
 
void toString (SmallVectorImpl< char > &Str, unsigned FormatPrecision=0, unsigned FormatMaxPadding=3) const
 Converts this value into a decimal string. More...
 
bool getExactInverse (APFloat *inv) const
 If this value has an exact multiplicative inverse, store it in inv and return true. More...
 
Constructors
 APFloat (const fltSemantics &)
 
 APFloat (const fltSemantics &, StringRef)
 
 APFloat (const fltSemantics &, integerPart)
 
 APFloat (const fltSemantics &, uninitializedTag)
 
 APFloat (const fltSemantics &, const APInt &)
 
 APFloat (double d)
 
 APFloat (float f)
 
 APFloat (const APFloat &)
 
 APFloat (APFloat &&)
 
 ~APFloat ()
 
Arithmetic
opStatus add (const APFloat &, roundingMode)
 
opStatus subtract (const APFloat &, roundingMode)
 
opStatus multiply (const APFloat &, roundingMode)
 
opStatus divide (const APFloat &, roundingMode)
 
opStatus remainder (const APFloat &)
 IEEE remainder. More...
 
opStatus mod (const APFloat &, roundingMode)
 C fmod, or llvm frem. More...
 
opStatus fusedMultiplyAdd (const APFloat &, const APFloat &, roundingMode)
 
opStatus roundToIntegral (roundingMode)
 
opStatus next (bool nextDown)
 IEEE-754R 5.3.1: nextUp/nextDown. More...
 
APFloat operator+ (const APFloat &RHS) const
 Operator+ overload which provides the default nmNearestTiesToEven rounding mode and no error checking. More...
 
APFloat operator- (const APFloat &RHS) const
 Operator- overload which provides the default nmNearestTiesToEven rounding mode and no error checking. More...
 
APFloat operator* (const APFloat &RHS) const
 Operator* overload which provides the default nmNearestTiesToEven rounding mode and no error checking. More...
 
APFloat operator/ (const APFloat &RHS) const
 Operator/ overload which provides the default nmNearestTiesToEven rounding mode and no error checking. More...
 
Conversions
opStatus convert (const fltSemantics &, roundingMode, bool *)
 APFloat::convert - convert a value of one floating point type to another. More...
 
opStatus convertToInteger (integerPart *, unsigned int, bool, roundingMode, bool *) const
 
opStatus convertToInteger (APSInt &, roundingMode, bool *) const
 
opStatus convertFromAPInt (const APInt &, bool, roundingMode)
 
opStatus convertFromSignExtendedInteger (const integerPart *, unsigned int, bool, roundingMode)
 
opStatus convertFromZeroExtendedInteger (const integerPart *, unsigned int, bool, roundingMode)
 
opStatus convertFromString (StringRef, roundingMode)
 
APInt bitcastToAPInt () const
 
double convertToDouble () const
 
float convertToFloat () const
 
IEEE-754R 5.7.2 General operations.
bool isNegative () const
 IEEE-754R isSignMinus: Returns true if and only if the current value is negative. More...
 
bool isNormal () const
 IEEE-754R isNormal: Returns true if and only if the current value is normal. More...
 
bool isFinite () const
 Returns true if and only if the current value is zero, subnormal, or normal. More...
 
bool isZero () const
 Returns true if and only if the float is plus or minus zero. More...
 
bool isDenormal () const
 IEEE-754R isSubnormal(): Returns true if and only if the float is a denormal. More...
 
bool isInfinity () const
 IEEE-754R isInfinite(): Returns true if and only if the float is infinity. More...
 
bool isNaN () const
 Returns true if and only if the float is a quiet or signaling NaN. More...
 
bool isSignaling () const
 Returns true if and only if the float is a signaling NaN. More...
 

Static Public Member Functions

static unsigned int semanticsPrecision (const fltSemantics &)
 
Convenience "constructors"
static APFloat getZero (const fltSemantics &Sem, bool Negative=false)
 Factory for Positive and Negative Zero. More...
 
static APFloat getInf (const fltSemantics &Sem, bool Negative=false)
 Factory for Positive and Negative Infinity. More...
 
static APFloat getNaN (const fltSemantics &Sem, bool Negative=false, unsigned type=0)
 Factory for QNaN values. More...
 
static APFloat getQNaN (const fltSemantics &Sem, bool Negative=false, const APInt *payload=nullptr)
 Factory for QNaN values. More...
 
static APFloat getSNaN (const fltSemantics &Sem, bool Negative=false, const APInt *payload=nullptr)
 Factory for SNaN values. More...
 
static APFloat getLargest (const fltSemantics &Sem, bool Negative=false)
 Returns the largest finite number in the given semantics. More...
 
static APFloat getSmallest (const fltSemantics &Sem, bool Negative=false)
 Returns the smallest (by magnitude) finite number in the given semantics. More...
 
static APFloat getSmallestNormalized (const fltSemantics &Sem, bool Negative=false)
 Returns the smallest (by magnitude) normalized finite number in the given semantics. More...
 
static APFloat getAllOnesValue (unsigned BitWidth, bool isIEEE=false)
 Returns a float which is bitcasted from an all one value int. More...
 
static unsigned getSizeInBits (const fltSemantics &Sem)
 Returns the size of the floating point number (in bits) in the given semantics. More...
 

Static Public Attributes

Floating Point Semantics.
static const fltSemantics IEEEhalf = { 15, -14, 11, 16 }
 
static const fltSemantics IEEEsingle = { 127, -126, 24, 32 }
 
static const fltSemantics IEEEdouble = { 1023, -1022, 53, 64 }
 
static const fltSemantics IEEEquad = { 16383, -16382, 113, 128 }
 
static const fltSemantics PPCDoubleDouble = { 1023, -1022 + 53, 53 + 53, 128 }
 
static const fltSemantics x87DoubleExtended = { 16383, -16382, 64, 80 }
 
static const fltSemantics Bogus = { 0, 0, 0, 0 }
 A Pseudo fltsemantic used to construct APFloats that cannot conflict with anything real. More...
 

Friends

hash_code hash_value (const APFloat &Arg)
 Overload to compute a hash code for an APFloat value. More...
 
int ilogb (const APFloat &Arg)
 Returns the exponent of the internal representation of the APFloat. More...
 
APFloat scalbn (APFloat X, int Exp)
 Returns: X * 2^Exp for integral exponents. More...
 

Sign operations.

static APFloat copySign (APFloat Value, const APFloat &Sign)
 A static helper to produce a copy of an APFloat value with its sign copied from some other APFloat. More...
 
void changeSign ()
 
void clearSign ()
 
void copySign (const APFloat &)
 

Simple Queries

fltCategory getCategory () const
 
const fltSemanticsgetSemantics () const
 
bool isNonZero () const
 
bool isFiniteNonZero () const
 
bool isPosZero () const
 
bool isNegZero () const
 
bool isSmallest () const
 Returns true if and only if the number has the smallest possible non-zero magnitude in the current semantics. More...
 
bool isLargest () const
 Returns true if and only if the number has the largest possible finite magnitude in the current semantics. More...
 

Detailed Description

A self-contained host- and target-independent arbitrary-precision floating-point software implementation.

APFloat uses bignum integer arithmetic as provided by static functions in the APInt class. The library will work with bignum integers whose parts are any unsigned type at least 16 bits wide, but 64 bits is recommended.

Written for clarity rather than speed, in particular with a view to use in the front-end of a cross compiler so that target arithmetic can be correctly performed on the host. Performance should nonetheless be reasonable, particularly for its intended use. It may be useful as a base implementation for a run-time library during development of a faster target-specific one.

All 5 rounding modes in the IEEE-754R draft are handled correctly for all implemented operations. Currently implemented operations are add, subtract, multiply, divide, fused-multiply-add, conversion-to-float, conversion-to-integer and conversion-from-integer. New rounding modes (e.g. away from zero) can be added with three or four lines of code.

Four formats are built-in: IEEE single precision, double precision, quadruple precision, and x87 80-bit extended double (when operating with full extended precision). Adding a new format that obeys IEEE semantics only requires adding two lines of code: a declaration and definition of the format.

All operations return the status of that operation as an exception bit-mask, so multiple operations can be done consecutively with their results or-ed together. The returned status can be useful for compiler diagnostics; e.g., inexact, underflow and overflow can be easily diagnosed on constant folding, and compiler optimizers can determine what exceptions would be raised by folding operations and optimize, or perhaps not optimize, accordingly.

At present, underflow tininess is detected after rounding; it should be straight forward to add support for the before-rounding case too.

The library reads hexadecimal floating point numbers as per C99, and correctly rounds if necessary according to the specified rounding mode. Syntax is required to have been validated by the caller. It also converts floating point numbers to hexadecimal text as per the C99 a and A conversions. The output precision (or alternatively the natural minimal precision) can be specified; if the requested precision is less than the natural precision the output is correctly rounded for the specified rounding mode.

It also reads decimal floating point numbers and correctly rounds according to the specified rounding mode.

Conversion to decimal text is not currently implemented.

Non-zero finite numbers are represented internally as a sign bit, a 16-bit signed exponent, and the significand as an array of integer parts. After normalization of a number of precision P the exponent is within the range of the format, and if the number is not denormal the P-th bit of the significand is set as an explicit integer bit. For denormals the most significant bit is shifted right so that the exponent is maintained at the format's minimum, so that the smallest denormal has just the least significant bit of the significand set. The sign of zeroes and infinities is significant; the exponent and significand of such numbers is not stored, but has a known implicit (deterministic) value: 0 for the significands, 0 for zero exponent, all 1 bits for infinity exponent. For NaNs the sign and significand are deterministic, although not really meaningful, and preserved in non-conversion operations. The exponent is implicitly all 1 bits.

APFloat does not provide any exception handling beyond default exception handling. We represent Signaling NaNs via IEEE-754R 2008 6.2.1 should clause by encoding Signaling NaNs with the first bit of its trailing significand as 0.

TODO

Some features that may or may not be worth adding:

Binary to decimal conversion (hard).

Optional ability to detect underflow tininess before rounding.

New formats: x87 in single and double precision mode (IEEE apart from extended exponent range) (hard).

New operations: sqrt, IEEE remainder, C90 fmod, nexttoward.

Definition at line 122 of file APFloat.h.

Member Typedef Documentation

typedef signed short llvm::APFloat::ExponentType

A signed type to represent a floating point numbers unbiased exponent.

Definition at line 126 of file APFloat.h.

Member Enumeration Documentation

IEEE-754R 5.11: Floating Point Comparison Relations.

Enumerator
cmpLessThan 
cmpEqual 
cmpGreaterThan 
cmpUnordered 

Definition at line 147 of file APFloat.h.

Category of internally-represented number.

Enumerator
fcInfinity 
fcNaN 
fcNormal 
fcZero 

Definition at line 176 of file APFloat.h.

Enumeration of ilogb error results.

Enumerator
IEK_Zero 
IEK_NaN 
IEK_Inf 

Definition at line 493 of file APFloat.h.

IEEE-754R 7: Default exception handling.

opUnderflow or opOverflow are always returned or-ed with opInexact.

Enumerator
opOK 
opInvalidOp 
opDivByZero 
opOverflow 
opUnderflow 
opInexact 

Definition at line 166 of file APFloat.h.

IEEE-754R 4.3: Rounding-direction attributes.

Enumerator
rmNearestTiesToEven 
rmTowardPositive 
rmTowardNegative 
rmTowardZero 
rmNearestTiesToAway 

Definition at line 155 of file APFloat.h.

Convenience enum used to construct an uninitialized APFloat.

Enumerator
uninitialized 

Definition at line 184 of file APFloat.h.

Constructor & Destructor Documentation

APFloat::APFloat ( const fltSemantics ourSemantics)

Definition at line 804 of file APFloat.cpp.

References fcZero.

Referenced by getAllOnesValue().

APFloat::APFloat ( const fltSemantics ourSemantics,
StringRef  text 
)

Definition at line 815 of file APFloat.cpp.

References convertFromString(), and rmNearestTiesToEven.

APFloat::APFloat ( const fltSemantics ourSemantics,
integerPart  value 
)
APFloat::APFloat ( const fltSemantics ourSemantics,
uninitializedTag  tag 
)

Definition at line 810 of file APFloat.cpp.

APFloat::APFloat ( const fltSemantics Sem,
const APInt API 
)

Definition at line 3455 of file APFloat.cpp.

APFloat::APFloat ( double  d)
explicit

Definition at line 3463 of file APFloat.cpp.

References llvm::APInt::doubleToBits(), and IEEEdouble.

APFloat::APFloat ( float  f)
explicit

Definition at line 3459 of file APFloat.cpp.

References llvm::APInt::floatToBits(), and IEEEsingle.

APFloat::APFloat ( const APFloat rhs)

Definition at line 820 of file APFloat.cpp.

APFloat::APFloat ( APFloat &&  rhs)

Definition at line 825 of file APFloat.cpp.

APFloat::~APFloat ( )

Definition at line 829 of file APFloat.cpp.

Member Function Documentation

APFloat::opStatus APFloat::add ( const APFloat rhs,
roundingMode  rounding_mode 
)
APInt APFloat::bitcastToAPInt ( ) const
bool APFloat::bitwiseIsEqual ( const APFloat rhs) const

Bitwise comparison for equality (QNaNs compare equal, 0!=-0).

Definition at line 771 of file APFloat.cpp.

References fcInfinity, fcZero, and isFiniteNonZero().

Referenced by llvm::DenseMapAPFloatKeyInfo::isEqual(), llvm::ConstantFP::isExactlyValue(), and llvm::X86TargetLowering::isFPImmLegal().

void APFloat::changeSign ( )
void APFloat::clearSign ( )
APFloat::cmpResult APFloat::compare ( const APFloat rhs) const
APFloat::opStatus APFloat::convert ( const fltSemantics toSemantics,
roundingMode  rounding_mode,
bool losesInfo 
)
APFloat::opStatus APFloat::convertFromAPInt ( const APInt Val,
bool  isSigned,
roundingMode  rounding_mode 
)
APFloat::opStatus APFloat::convertFromSignExtendedInteger ( const integerPart src,
unsigned int  srcCount,
bool  isSigned,
roundingMode  rounding_mode 
)
APFloat::opStatus APFloat::convertFromString ( StringRef  str,
roundingMode  rounding_mode 
)

Definition at line 2645 of file APFloat.cpp.

References llvm::StringRef::begin(), llvm::StringRef::empty(), opOK, and llvm::StringRef::size().

Referenced by APFloat().

APFloat::opStatus APFloat::convertFromZeroExtendedInteger ( const integerPart parts,
unsigned int  width,
bool  isSigned,
roundingMode  rounding_mode 
)
double APFloat::convertToDouble ( ) const
float APFloat::convertToFloat ( ) const
unsigned int APFloat::convertToHexString ( char *  dst,
unsigned int  hexDigits,
bool  upperCase,
roundingMode  rounding_mode 
) const

Write out a hexadecimal representation of the floating point value to DST, which must be of sufficient size, in the C99 form [-]0xh.hhhhp[+-]d.

Return the number of characters written, excluding the terminating NUL.

Definition at line 2697 of file APFloat.cpp.

References fcInfinity, fcNaN, fcNormal, fcZero, infinityL, infinityU, NaNL, and NaNU.

APFloat::opStatus APFloat::convertToInteger ( integerPart parts,
unsigned int  width,
bool  isSigned,
roundingMode  rounding_mode,
bool isExact 
) const
APFloat::opStatus APFloat::convertToInteger ( APSInt result,
roundingMode  rounding_mode,
bool isExact 
) const
void APFloat::copySign ( const APFloat rhs)
static APFloat llvm::APFloat::copySign ( APFloat  Value,
const APFloat Sign 
)
inlinestatic

A static helper to produce a copy of an APFloat value with its sign copied from some other APFloat.

Definition at line 348 of file APFloat.h.

References copySign().

APFloat::opStatus APFloat::divide ( const APFloat rhs,
roundingMode  rounding_mode 
)
APFloat::opStatus APFloat::fusedMultiplyAdd ( const APFloat multiplicand,
const APFloat addend,
roundingMode  rounding_mode 
)
APFloat APFloat::getAllOnesValue ( unsigned  BitWidth,
bool  isIEEE = false 
)
static

Returns a float which is bitcasted from an all one value int.

Parameters
BitWidth- Select float type
isIEEE- If 128 bit number, select between PPC and IEEE

Definition at line 3354 of file APFloat.cpp.

References APFloat(), llvm::APInt::getAllOnesValue(), IEEEdouble, IEEEhalf, IEEEquad, IEEEsingle, llvm_unreachable, PPCDoubleDouble, and x87DoubleExtended.

Referenced by llvm::Constant::getAllOnesValue().

fltCategory llvm::APFloat::getCategory ( ) const
inline

Definition at line 434 of file APFloat.h.

bool APFloat::getExactInverse ( APFloat inv) const

If this value has an exact multiplicative inverse, store it in inv and return true.

Definition at line 3754 of file APFloat.cpp.

References divide(), isDenormal(), isFiniteNonZero(), opOK, llvm::fltSemantics::precision, and rmNearestTiesToEven.

Referenced by CvtFDivConstToReciprocal().

static APFloat llvm::APFloat::getInf ( const fltSemantics Sem,
bool  Negative = false 
)
inlinestatic

Factory for Positive and Negative Infinity.

Parameters
NegativeTrue iff the number should be negative.

Definition at line 222 of file APFloat.h.

References uninitialized.

Referenced by llvm::ConstantFP::getInfinity(), and llvm::scalbn().

APFloat APFloat::getLargest ( const fltSemantics Sem,
bool  Negative = false 
)
static

Returns the largest finite number in the given semantics.

Parameters
Negative- True iff the number should be negative

Definition at line 3417 of file APFloat.cpp.

References uninitialized.

static APFloat llvm::APFloat::getNaN ( const fltSemantics Sem,
bool  Negative = false,
unsigned  type = 0 
)
inlinestatic

Factory for QNaN values.

Parameters
Negative- True iff the NaN generated should be negative.
type- The unspecified fill bits for creating the NaN, 0 by default. The value is truncated as necessary.

Definition at line 233 of file APFloat.h.

References getQNaN().

Referenced by llvm::ConstantFP::getNaN().

static APFloat llvm::APFloat::getQNaN ( const fltSemantics Sem,
bool  Negative = false,
const APInt payload = nullptr 
)
inlinestatic

Factory for QNaN values.

Definition at line 244 of file APFloat.h.

Referenced by getNaN().

const fltSemantics& llvm::APFloat::getSemantics ( ) const
inline
unsigned APFloat::getSizeInBits ( const fltSemantics Sem)
static

Returns the size of the floating point number (in bits) in the given semantics.

Definition at line 3374 of file APFloat.cpp.

References llvm::fltSemantics::sizeInBits.

APFloat APFloat::getSmallest ( const fltSemantics Sem,
bool  Negative = false 
)
static

Returns the smallest (by magnitude) finite number in the given semantics.

Might be denormalized, which implies a relative loss of precision.

Parameters
Negative- True iff the number should be negative

Definition at line 3427 of file APFloat.cpp.

References uninitialized.

APFloat APFloat::getSmallestNormalized ( const fltSemantics Sem,
bool  Negative = false 
)
static

Returns the smallest (by magnitude) normalized finite number in the given semantics.

Parameters
Negative- True iff the number should be negative

Definition at line 3437 of file APFloat.cpp.

References fcNormal, llvm::fltSemantics::minExponent, partCountForBits(), llvm::fltSemantics::precision, and uninitialized.

Referenced by llvm::InstCombiner::visitFCmpInst().

static APFloat llvm::APFloat::getSNaN ( const fltSemantics Sem,
bool  Negative = false,
const APInt payload = nullptr 
)
inlinestatic

Factory for SNaN values.

Definition at line 250 of file APFloat.h.

static APFloat llvm::APFloat::getZero ( const fltSemantics Sem,
bool  Negative = false 
)
inlinestatic

Factory for Positive and Negative Zero.

Parameters
NegativeTrue iff the number should be negative.

Definition at line 213 of file APFloat.h.

References uninitialized.

Referenced by llvm::ExecutionEngine::getConstantValue(), llvm::ConstantFP::getNegativeZero(), llvm::Constant::getNullValue(), llvm::scalbn(), and llvm::X86TargetLowering::X86TargetLowering().

bool APFloat::isDenormal ( ) const

IEEE-754R isSubnormal(): Returns true if and only if the float is a denormal.

Definition at line 703 of file APFloat.cpp.

References isFiniteNonZero(), llvm::fltSemantics::minExponent, llvm::fltSemantics::precision, and llvm::APInt::tcExtractBit().

Referenced by getExactInverse(), isNormal(), and next().

bool llvm::APFloat::isFinite ( ) const
inline

Returns true if and only if the current value is zero, subnormal, or normal.

This means that the value is not infinite or NaN.

Definition at line 411 of file APFloat.h.

References isInfinity(), and isNaN().

Referenced by fusedMultiplyAdd(), and isFiniteNonZero().

bool llvm::APFloat::isFiniteNonZero ( ) const
inline
bool llvm::APFloat::isInfinity ( ) const
inline

IEEE-754R isInfinite(): Returns true if and only if the float is infinity.

Definition at line 421 of file APFloat.h.

References fcInfinity.

Referenced by isFinite(), llvm::ConstantFP::isInfinity(), and llvm::scalbn().

bool APFloat::isLargest ( ) const

Returns true if and only if the number has the largest possible finite magnitude in the current semantics.

Definition at line 763 of file APFloat.cpp.

References isFiniteNonZero(), and llvm::fltSemantics::maxExponent.

Referenced by next().

bool llvm::APFloat::isNaN ( ) const
inline

Returns true if and only if the float is a quiet or signaling NaN.

Definition at line 424 of file APFloat.h.

References fcNaN.

Referenced by llvm::InstCombiner::FoldFCmp_IntToFP_Cst(), llvm::hash_value(), isFinite(), llvm::ConstantFP::isNaN(), isSignaling(), llvm::maxnum(), llvm::minnum(), and llvm::scalbn().

bool llvm::APFloat::isNegative ( ) const
inline

IEEE-754R isSignMinus: Returns true if and only if the current value is negative.

This applies to zeros and NaNs as well.

Definition at line 399 of file APFloat.h.

Referenced by llvm::InstCombiner::FoldFCmp_IntToFP_Cst(), llvm::ConstantFP::isNegative(), isNegZero(), isPosZero(), next(), roundToIntegral(), llvm::scalbn(), and toString().

bool llvm::APFloat::isNegZero ( ) const
inline

Definition at line 439 of file APFloat.h.

References isNegative(), and isZero().

Referenced by llvm::SystemZTargetLowering::isFPImmLegal().

bool llvm::APFloat::isNonZero ( ) const
inline

Definition at line 436 of file APFloat.h.

References fcZero.

bool llvm::APFloat::isNormal ( ) const
inline

IEEE-754R isNormal: Returns true if and only if the current value is normal.

This implies that the current value of the float is not zero, subnormal, infinite, or NaN following the definition of normality from IEEE-754R.

Definition at line 405 of file APFloat.h.

References isDenormal(), and isFiniteNonZero().

Referenced by isNormalFp().

bool llvm::APFloat::isPosZero ( ) const
inline
bool APFloat::isSignaling ( ) const

Returns true if and only if the float is a signaling NaN.

Definition at line 3783 of file APFloat.cpp.

References isNaN(), llvm::fltSemantics::precision, and llvm::APInt::tcExtractBit().

Referenced by next().

bool APFloat::isSmallest ( ) const

Returns true if and only if the number has the smallest possible non-zero magnitude in the current semantics.

Definition at line 710 of file APFloat.cpp.

References isFiniteNonZero(), and llvm::fltSemantics::minExponent.

Referenced by next().

bool llvm::APFloat::isZero ( ) const
inline
APFloat::opStatus APFloat::mod ( const APFloat rhs,
roundingMode  rounding_mode 
)
APFloat::opStatus APFloat::multiply ( const APFloat rhs,
roundingMode  rounding_mode 
)
bool llvm::APFloat::needsCleanup ( ) const
inline

Returns whether this instance allocated memory.

Definition at line 205 of file APFloat.h.

APFloat::opStatus APFloat::next ( bool  nextDown)

IEEE-754R 5.3.1: nextUp/nextDown.

IEEE-754R 2008 5.3.1: nextUp/nextDown.

NOTE since nextDown(x) = -nextUp(-x), we only implement nextUp with appropriate sign switching before/after the computation.

Definition at line 3796 of file APFloat.cpp.

References changeSign(), fcInfinity, fcNaN, fcNormal, fcZero, isDenormal(), isLargest(), isNegative(), isSignaling(), isSmallest(), llvm::fltSemantics::maxExponent, llvm::fltSemantics::minExponent, opInvalidOp, opOK, llvm::fltSemantics::precision, llvm::APInt::tcDecrement(), llvm::APInt::tcSet(), and llvm::APInt::tcSetBit().

APFloat llvm::APFloat::operator* ( const APFloat RHS) const
inline

Operator* overload which provides the default nmNearestTiesToEven rounding mode and no error checking.

Definition at line 323 of file APFloat.h.

References multiply(), and rmNearestTiesToEven.

APFloat llvm::APFloat::operator+ ( const APFloat RHS) const
inline

Operator+ overload which provides the default nmNearestTiesToEven rounding mode and no error checking.

Definition at line 307 of file APFloat.h.

References add(), and rmNearestTiesToEven.

APFloat llvm::APFloat::operator- ( const APFloat RHS) const
inline

Operator- overload which provides the default nmNearestTiesToEven rounding mode and no error checking.

Definition at line 315 of file APFloat.h.

References rmNearestTiesToEven, and subtract().

APFloat llvm::APFloat::operator/ ( const APFloat RHS) const
inline

Operator/ overload which provides the default nmNearestTiesToEven rounding mode and no error checking.

Definition at line 331 of file APFloat.h.

References divide(), and rmNearestTiesToEven.

APFloat & APFloat::operator= ( const APFloat rhs)

Definition at line 675 of file APFloat.cpp.

APFloat & APFloat::operator= ( APFloat &&  rhs)

Definition at line 689 of file APFloat.cpp.

References Bogus.

bool llvm::APFloat::operator== ( const APFloat ) const
delete

The definition of equality is not straightforward for floating point, so we won't use operator==.

Use one of the following, or write whatever it is you really mean.

void APFloat::Profile ( FoldingSetNodeID NID) const

Used to insert APFloat objects, or objects that contain APFloat objects, into FoldingSets.

Definition at line 835 of file APFloat.cpp.

References llvm::FoldingSetNodeID::Add(), and bitcastToAPInt().

APFloat::opStatus APFloat::remainder ( const APFloat rhs)
APFloat::opStatus APFloat::roundToIntegral ( roundingMode  rounding_mode)
unsigned int APFloat::semanticsPrecision ( const fltSemantics semantics)
static

Definition at line 846 of file APFloat.cpp.

References llvm::fltSemantics::precision.

Referenced by FoldIntToFPToInt(), and roundToIntegral().

APFloat::opStatus APFloat::subtract ( const APFloat rhs,
roundingMode  rounding_mode 
)
void APFloat::toString ( SmallVectorImpl< char > &  Str,
unsigned  FormatPrecision = 0,
unsigned  FormatMaxPadding = 3 
) const

Converts this value into a decimal string.

Parameters
FormatPrecisionThe maximum number of digits of precision to output. If there are fewer digits available, zero padding will not be used unless the value is integral and small enough to be expressed in FormatPrecision digits. 0 means to use the natural precision of the number.
FormatMaxPaddingThe maximum number of zeros to consider inserting before falling back to scientific notation. 0 means to always use scientific notation.

Number Precision MaxPadding Result


1.01E+4 5 2 10100 1.01E+4 4 2 1.01E+4 1.01E+4 5 1 1.01E+4 1.01E-2 5 2 0.0101 1.01E-2 4 2 0.0101 1.01E-2 4 1 1.01E-2

Definition at line 3551 of file APFloat.cpp.

References llvm::sys::path::append(), llvm::APInt::countTrailingZeros(), llvm::SmallVectorBase::empty(), fcInfinity, fcNaN, fcNormal, fcZero, llvm::APInt::getBitWidth(), llvm::APInt::getZExtValue(), I, isNegative(), llvm::APInt::lshr(), llvm::makeArrayRef(), partCountForBits(), llvm::fltSemantics::precision, llvm::SmallVectorTemplateBase< T, isPodLike >::push_back(), llvm::SmallVectorTemplateBase< T, isPodLike< T >::value >::push_back(), llvm::SmallVectorTemplateCommon< T >::size(), llvm::APInt::udivrem(), and llvm::APInt::zext().

Referenced by emitGlobalConstantFP(), and toStringAPFloat().

Friends And Related Function Documentation

hash_code hash_value ( const APFloat Arg)
friend

Overload to compute a hash code for an APFloat value.

Note that the use of hash codes for floating point values is in general frought with peril. Equality is hard to define for these values. For example, should negative and positive zero hash to different codes? Are they equal or not? This hash value implementation specifically emphasizes producing different codes for different inputs in order to be used in canonicalization and memoization. As such, equality is bitwiseIsEqual, and 0 != -0.

These additional declarations are required in order to compile LLVM with IBM xlC compiler.

int ilogb ( const APFloat Arg)
friend

Returns the exponent of the internal representation of the APFloat.

Because the radix of APFloat is 2, this is equivalent to floor(log2(x)). For special APFloat values, this returns special error codes:

NaN -> IEK_NaN 0 -> IEK_Zero Inf -> IEK_Inf

Definition at line 508 of file APFloat.h.

APFloat scalbn ( APFloat  X,
int  Exp 
)
friend

Returns: X * 2^Exp for integral exponents.

Member Data Documentation

const fltSemantics llvm::APFloat::Bogus = { 0, 0, 0, 0 }
static

A Pseudo fltsemantic used to construct APFloats that cannot conflict with anything real.

Definition at line 140 of file APFloat.h.

Referenced by llvm::ConstantFoldCastInstruction(), llvm::DenseMapAPFloatKeyInfo::getEmptyKey(), llvm::DenseMapAPFloatKeyInfo::getTombstoneKey(), and operator=().

const fltSemantics llvm::APFloat::IEEEdouble = { 1023, -1022, 53, 64 }
static
const fltSemantics llvm::APFloat::IEEEhalf = { 15, -14, 11, 16 }
static
const fltSemantics llvm::APFloat::IEEEquad = { 16383, -16382, 113, 128 }
static
const fltSemantics llvm::APFloat::IEEEsingle = { 127, -126, 24, 32 }
static
const fltSemantics llvm::APFloat::PPCDoubleDouble = { 1023, -1022 + 53, 53 + 53, 128 }
static
const fltSemantics llvm::APFloat::x87DoubleExtended = { 16383, -16382, 64, 80 }
static

The documentation for this class was generated from the following files: