1193323Sed//== llvm/Support/APFloat.h - Arbitrary Precision Floating Point -*- C++ -*-==// 2193323Sed// 3193323Sed// The LLVM Compiler Infrastructure 4193323Sed// 5193323Sed// This file is distributed under the University of Illinois Open Source 6193323Sed// License. See LICENSE.TXT for details. 7193323Sed// 8193323Sed//===----------------------------------------------------------------------===// 9263508Sdim/// 10263508Sdim/// \file 11263508Sdim/// \brief 12263508Sdim/// This file declares a class to represent arbitrary precision floating point 13263508Sdim/// values and provide a variety of arithmetic operations on them. 14263508Sdim/// 15193323Sed//===----------------------------------------------------------------------===// 16193323Sed 17263508Sdim#ifndef LLVM_ADT_APFLOAT_H 18263508Sdim#define LLVM_ADT_APFLOAT_H 19193323Sed 20263508Sdim#include "llvm/ADT/APInt.h" 21193323Sed 22263508Sdimnamespace llvm { 23193323Sed 24263508Sdimstruct fltSemantics; 25263508Sdimclass APSInt; 26263508Sdimclass StringRef; 27193323Sed 28263508Sdim/// Enum that represents what fraction of the LSB truncated bits of an fp number 29263508Sdim/// represent. 30263508Sdim/// 31263508Sdim/// This essentially combines the roles of guard and sticky bits. 32263508Sdimenum lostFraction { // Example of truncated bits: 33263508Sdim lfExactlyZero, // 000000 34263508Sdim lfLessThanHalf, // 0xxxxx x's not all zero 35263508Sdim lfExactlyHalf, // 100000 36263508Sdim lfMoreThanHalf // 1xxxxx x's not all zero 37263508Sdim}; 38193323Sed 39263508Sdim/// \brief A self-contained host- and target-independent arbitrary-precision 40263508Sdim/// floating-point software implementation. 41263508Sdim/// 42263508Sdim/// APFloat uses bignum integer arithmetic as provided by static functions in 43263508Sdim/// the APInt class. The library will work with bignum integers whose parts are 44263508Sdim/// any unsigned type at least 16 bits wide, but 64 bits is recommended. 45263508Sdim/// 46263508Sdim/// Written for clarity rather than speed, in particular with a view to use in 47263508Sdim/// the front-end of a cross compiler so that target arithmetic can be correctly 48263508Sdim/// performed on the host. Performance should nonetheless be reasonable, 49263508Sdim/// particularly for its intended use. It may be useful as a base 50263508Sdim/// implementation for a run-time library during development of a faster 51263508Sdim/// target-specific one. 52263508Sdim/// 53263508Sdim/// All 5 rounding modes in the IEEE-754R draft are handled correctly for all 54263508Sdim/// implemented operations. Currently implemented operations are add, subtract, 55263508Sdim/// multiply, divide, fused-multiply-add, conversion-to-float, 56263508Sdim/// conversion-to-integer and conversion-from-integer. New rounding modes 57263508Sdim/// (e.g. away from zero) can be added with three or four lines of code. 58263508Sdim/// 59263508Sdim/// Four formats are built-in: IEEE single precision, double precision, 60263508Sdim/// quadruple precision, and x87 80-bit extended double (when operating with 61263508Sdim/// full extended precision). Adding a new format that obeys IEEE semantics 62263508Sdim/// only requires adding two lines of code: a declaration and definition of the 63263508Sdim/// format. 64263508Sdim/// 65263508Sdim/// All operations return the status of that operation as an exception bit-mask, 66263508Sdim/// so multiple operations can be done consecutively with their results or-ed 67263508Sdim/// together. The returned status can be useful for compiler diagnostics; e.g., 68263508Sdim/// inexact, underflow and overflow can be easily diagnosed on constant folding, 69263508Sdim/// and compiler optimizers can determine what exceptions would be raised by 70263508Sdim/// folding operations and optimize, or perhaps not optimize, accordingly. 71263508Sdim/// 72263508Sdim/// At present, underflow tininess is detected after rounding; it should be 73263508Sdim/// straight forward to add support for the before-rounding case too. 74263508Sdim/// 75263508Sdim/// The library reads hexadecimal floating point numbers as per C99, and 76263508Sdim/// correctly rounds if necessary according to the specified rounding mode. 77263508Sdim/// Syntax is required to have been validated by the caller. It also converts 78263508Sdim/// floating point numbers to hexadecimal text as per the C99 %a and %A 79263508Sdim/// conversions. The output precision (or alternatively the natural minimal 80263508Sdim/// precision) can be specified; if the requested precision is less than the 81263508Sdim/// natural precision the output is correctly rounded for the specified rounding 82263508Sdim/// mode. 83263508Sdim/// 84263508Sdim/// It also reads decimal floating point numbers and correctly rounds according 85263508Sdim/// to the specified rounding mode. 86263508Sdim/// 87263508Sdim/// Conversion to decimal text is not currently implemented. 88263508Sdim/// 89263508Sdim/// Non-zero finite numbers are represented internally as a sign bit, a 16-bit 90263508Sdim/// signed exponent, and the significand as an array of integer parts. After 91263508Sdim/// normalization of a number of precision P the exponent is within the range of 92263508Sdim/// the format, and if the number is not denormal the P-th bit of the 93263508Sdim/// significand is set as an explicit integer bit. For denormals the most 94263508Sdim/// significant bit is shifted right so that the exponent is maintained at the 95263508Sdim/// format's minimum, so that the smallest denormal has just the least 96263508Sdim/// significant bit of the significand set. The sign of zeroes and infinities 97263508Sdim/// is significant; the exponent and significand of such numbers is not stored, 98263508Sdim/// but has a known implicit (deterministic) value: 0 for the significands, 0 99263508Sdim/// for zero exponent, all 1 bits for infinity exponent. For NaNs the sign and 100263508Sdim/// significand are deterministic, although not really meaningful, and preserved 101263508Sdim/// in non-conversion operations. The exponent is implicitly all 1 bits. 102263508Sdim/// 103263508Sdim/// APFloat does not provide any exception handling beyond default exception 104263508Sdim/// handling. We represent Signaling NaNs via IEEE-754R 2008 6.2.1 should clause 105263508Sdim/// by encoding Signaling NaNs with the first bit of its trailing significand as 106263508Sdim/// 0. 107263508Sdim/// 108263508Sdim/// TODO 109263508Sdim/// ==== 110263508Sdim/// 111263508Sdim/// Some features that may or may not be worth adding: 112263508Sdim/// 113263508Sdim/// Binary to decimal conversion (hard). 114263508Sdim/// 115263508Sdim/// Optional ability to detect underflow tininess before rounding. 116263508Sdim/// 117263508Sdim/// New formats: x87 in single and double precision mode (IEEE apart from 118263508Sdim/// extended exponent range) (hard). 119263508Sdim/// 120263508Sdim/// New operations: sqrt, IEEE remainder, C90 fmod, nexttoward. 121263508Sdim/// 122263508Sdimclass APFloat { 123263508Sdimpublic: 124193323Sed 125263508Sdim /// A signed type to represent a floating point numbers unbiased exponent. 126263508Sdim typedef signed short ExponentType; 127193323Sed 128263508Sdim /// \name Floating Point Semantics. 129263508Sdim /// @{ 130193323Sed 131263508Sdim static const fltSemantics IEEEhalf; 132263508Sdim static const fltSemantics IEEEsingle; 133263508Sdim static const fltSemantics IEEEdouble; 134263508Sdim static const fltSemantics IEEEquad; 135263508Sdim static const fltSemantics PPCDoubleDouble; 136263508Sdim static const fltSemantics x87DoubleExtended; 137193323Sed 138263508Sdim /// A Pseudo fltsemantic used to construct APFloats that cannot conflict with 139263508Sdim /// anything real. 140263508Sdim static const fltSemantics Bogus; 141193323Sed 142263508Sdim /// @} 143193323Sed 144263508Sdim static unsigned int semanticsPrecision(const fltSemantics &); 145193323Sed 146263508Sdim /// IEEE-754R 5.11: Floating Point Comparison Relations. 147263508Sdim enum cmpResult { 148263508Sdim cmpLessThan, 149263508Sdim cmpEqual, 150263508Sdim cmpGreaterThan, 151263508Sdim cmpUnordered 152263508Sdim }; 153193323Sed 154263508Sdim /// IEEE-754R 4.3: Rounding-direction attributes. 155263508Sdim enum roundingMode { 156263508Sdim rmNearestTiesToEven, 157263508Sdim rmTowardPositive, 158263508Sdim rmTowardNegative, 159263508Sdim rmTowardZero, 160263508Sdim rmNearestTiesToAway 161263508Sdim }; 162193323Sed 163263508Sdim /// IEEE-754R 7: Default exception handling. 164263508Sdim /// 165263508Sdim /// opUnderflow or opOverflow are always returned or-ed with opInexact. 166263508Sdim enum opStatus { 167263508Sdim opOK = 0x00, 168263508Sdim opInvalidOp = 0x01, 169263508Sdim opDivByZero = 0x02, 170263508Sdim opOverflow = 0x04, 171263508Sdim opUnderflow = 0x08, 172263508Sdim opInexact = 0x10 173263508Sdim }; 174193323Sed 175263508Sdim /// Category of internally-represented number. 176263508Sdim enum fltCategory { 177263508Sdim fcInfinity, 178263508Sdim fcNaN, 179263508Sdim fcNormal, 180263508Sdim fcZero 181263508Sdim }; 182193323Sed 183263508Sdim /// Convenience enum used to construct an uninitialized APFloat. 184263508Sdim enum uninitializedTag { 185263508Sdim uninitialized 186263508Sdim }; 187193323Sed 188263508Sdim /// \name Constructors 189263508Sdim /// @{ 190193323Sed 191263508Sdim APFloat(const fltSemantics &); // Default construct to 0.0 192263508Sdim APFloat(const fltSemantics &, StringRef); 193263508Sdim APFloat(const fltSemantics &, integerPart); 194263508Sdim APFloat(const fltSemantics &, uninitializedTag); 195263508Sdim APFloat(const fltSemantics &, const APInt &); 196263508Sdim explicit APFloat(double d); 197263508Sdim explicit APFloat(float f); 198263508Sdim APFloat(const APFloat &); 199263508Sdim ~APFloat(); 200193323Sed 201263508Sdim /// @} 202193323Sed 203263508Sdim /// \brief Returns whether this instance allocated memory. 204263508Sdim bool needsCleanup() const { return partCount() > 1; } 205193323Sed 206263508Sdim /// \name Convenience "constructors" 207263508Sdim /// @{ 208193323Sed 209263508Sdim /// Factory for Positive and Negative Zero. 210263508Sdim /// 211263508Sdim /// \param Negative True iff the number should be negative. 212263508Sdim static APFloat getZero(const fltSemantics &Sem, bool Negative = false) { 213263508Sdim APFloat Val(Sem, uninitialized); 214263508Sdim Val.makeZero(Negative); 215263508Sdim return Val; 216263508Sdim } 217193323Sed 218263508Sdim /// Factory for Positive and Negative Infinity. 219263508Sdim /// 220263508Sdim /// \param Negative True iff the number should be negative. 221263508Sdim static APFloat getInf(const fltSemantics &Sem, bool Negative = false) { 222263508Sdim APFloat Val(Sem, uninitialized); 223263508Sdim Val.makeInf(Negative); 224263508Sdim return Val; 225263508Sdim } 226193323Sed 227263508Sdim /// Factory for QNaN values. 228263508Sdim /// 229263508Sdim /// \param Negative - True iff the NaN generated should be negative. 230263508Sdim /// \param type - The unspecified fill bits for creating the NaN, 0 by 231263508Sdim /// default. The value is truncated as necessary. 232263508Sdim static APFloat getNaN(const fltSemantics &Sem, bool Negative = false, 233263508Sdim unsigned type = 0) { 234263508Sdim if (type) { 235263508Sdim APInt fill(64, type); 236263508Sdim return getQNaN(Sem, Negative, &fill); 237263508Sdim } else { 238263508Sdim return getQNaN(Sem, Negative, 0); 239263508Sdim } 240263508Sdim } 241193323Sed 242263508Sdim /// Factory for QNaN values. 243263508Sdim static APFloat getQNaN(const fltSemantics &Sem, bool Negative = false, 244263508Sdim const APInt *payload = 0) { 245263508Sdim return makeNaN(Sem, false, Negative, payload); 246263508Sdim } 247193323Sed 248263508Sdim /// Factory for SNaN values. 249263508Sdim static APFloat getSNaN(const fltSemantics &Sem, bool Negative = false, 250263508Sdim const APInt *payload = 0) { 251263508Sdim return makeNaN(Sem, true, Negative, payload); 252263508Sdim } 253193323Sed 254263508Sdim /// Returns the largest finite number in the given semantics. 255263508Sdim /// 256263508Sdim /// \param Negative - True iff the number should be negative 257263508Sdim static APFloat getLargest(const fltSemantics &Sem, bool Negative = false); 258193323Sed 259263508Sdim /// Returns the smallest (by magnitude) finite number in the given semantics. 260263508Sdim /// Might be denormalized, which implies a relative loss of precision. 261263508Sdim /// 262263508Sdim /// \param Negative - True iff the number should be negative 263263508Sdim static APFloat getSmallest(const fltSemantics &Sem, bool Negative = false); 264193323Sed 265263508Sdim /// Returns the smallest (by magnitude) normalized finite number in the given 266263508Sdim /// semantics. 267263508Sdim /// 268263508Sdim /// \param Negative - True iff the number should be negative 269263508Sdim static APFloat getSmallestNormalized(const fltSemantics &Sem, 270263508Sdim bool Negative = false); 271204642Srdivacky 272263508Sdim /// Returns a float which is bitcasted from an all one value int. 273263508Sdim /// 274263508Sdim /// \param BitWidth - Select float type 275263508Sdim /// \param isIEEE - If 128 bit number, select between PPC and IEEE 276263508Sdim static APFloat getAllOnesValue(unsigned BitWidth, bool isIEEE = false); 277193323Sed 278263508Sdim /// @} 279201360Srdivacky 280263508Sdim /// Used to insert APFloat objects, or objects that contain APFloat objects, 281263508Sdim /// into FoldingSets. 282263508Sdim void Profile(FoldingSetNodeID &NID) const; 283193323Sed 284263508Sdim /// \brief Used by the Bitcode serializer to emit APInts to Bitcode. 285263508Sdim void Emit(Serializer &S) const; 286204642Srdivacky 287263508Sdim /// \brief Used by the Bitcode deserializer to deserialize APInts. 288263508Sdim static APFloat ReadVal(Deserializer &D); 289204642Srdivacky 290263508Sdim /// \name Arithmetic 291263508Sdim /// @{ 292201360Srdivacky 293263508Sdim opStatus add(const APFloat &, roundingMode); 294263508Sdim opStatus subtract(const APFloat &, roundingMode); 295263508Sdim opStatus multiply(const APFloat &, roundingMode); 296263508Sdim opStatus divide(const APFloat &, roundingMode); 297263508Sdim /// IEEE remainder. 298263508Sdim opStatus remainder(const APFloat &); 299263508Sdim /// C fmod, or llvm frem. 300263508Sdim opStatus mod(const APFloat &, roundingMode); 301263508Sdim opStatus fusedMultiplyAdd(const APFloat &, const APFloat &, roundingMode); 302263508Sdim opStatus roundToIntegral(roundingMode); 303263508Sdim /// IEEE-754R 5.3.1: nextUp/nextDown. 304263508Sdim opStatus next(bool nextDown); 305201360Srdivacky 306263508Sdim /// @} 307201360Srdivacky 308263508Sdim /// \name Sign operations. 309263508Sdim /// @{ 310218893Sdim 311263508Sdim void changeSign(); 312263508Sdim void clearSign(); 313263508Sdim void copySign(const APFloat &); 314193323Sed 315263508Sdim /// @} 316193323Sed 317263508Sdim /// \name Conversions 318263508Sdim /// @{ 319193323Sed 320263508Sdim opStatus convert(const fltSemantics &, roundingMode, bool *); 321263508Sdim opStatus convertToInteger(integerPart *, unsigned int, bool, roundingMode, 322263508Sdim bool *) const; 323263508Sdim opStatus convertToInteger(APSInt &, roundingMode, bool *) const; 324263508Sdim opStatus convertFromAPInt(const APInt &, bool, roundingMode); 325263508Sdim opStatus convertFromSignExtendedInteger(const integerPart *, unsigned int, 326263508Sdim bool, roundingMode); 327263508Sdim opStatus convertFromZeroExtendedInteger(const integerPart *, unsigned int, 328263508Sdim bool, roundingMode); 329263508Sdim opStatus convertFromString(StringRef, roundingMode); 330263508Sdim APInt bitcastToAPInt() const; 331263508Sdim double convertToDouble() const; 332263508Sdim float convertToFloat() const; 333193323Sed 334263508Sdim /// @} 335193323Sed 336263508Sdim /// The definition of equality is not straightforward for floating point, so 337263508Sdim /// we won't use operator==. Use one of the following, or write whatever it 338263508Sdim /// is you really mean. 339263508Sdim bool operator==(const APFloat &) const LLVM_DELETED_FUNCTION; 340193323Sed 341263508Sdim /// IEEE comparison with another floating point number (NaNs compare 342263508Sdim /// unordered, 0==-0). 343263508Sdim cmpResult compare(const APFloat &) const; 344193323Sed 345263508Sdim /// Bitwise comparison for equality (QNaNs compare equal, 0!=-0). 346263508Sdim bool bitwiseIsEqual(const APFloat &) const; 347193323Sed 348263508Sdim /// Write out a hexadecimal representation of the floating point value to DST, 349263508Sdim /// which must be of sufficient size, in the C99 form [-]0xh.hhhhp[+-]d. 350263508Sdim /// Return the number of characters written, excluding the terminating NUL. 351263508Sdim unsigned int convertToHexString(char *dst, unsigned int hexDigits, 352263508Sdim bool upperCase, roundingMode) const; 353193323Sed 354263508Sdim /// \name IEEE-754R 5.7.2 General operations. 355263508Sdim /// @{ 356193323Sed 357263508Sdim /// IEEE-754R isSignMinus: Returns true if and only if the current value is 358263508Sdim /// negative. 359263508Sdim /// 360263508Sdim /// This applies to zeros and NaNs as well. 361263508Sdim bool isNegative() const { return sign; } 362193323Sed 363263508Sdim /// IEEE-754R isNormal: Returns true if and only if the current value is normal. 364263508Sdim /// 365263508Sdim /// This implies that the current value of the float is not zero, subnormal, 366263508Sdim /// infinite, or NaN following the definition of normality from IEEE-754R. 367263508Sdim bool isNormal() const { return !isDenormal() && isFiniteNonZero(); } 368193323Sed 369263508Sdim /// Returns true if and only if the current value is zero, subnormal, or 370263508Sdim /// normal. 371263508Sdim /// 372263508Sdim /// This means that the value is not infinite or NaN. 373263508Sdim bool isFinite() const { return !isNaN() && !isInfinity(); } 374193323Sed 375263508Sdim /// Returns true if and only if the float is plus or minus zero. 376263508Sdim bool isZero() const { return category == fcZero; } 377201360Srdivacky 378263508Sdim /// IEEE-754R isSubnormal(): Returns true if and only if the float is a 379263508Sdim /// denormal. 380263508Sdim bool isDenormal() const; 381221345Sdim 382263508Sdim /// IEEE-754R isInfinite(): Returns true if and only if the float is infinity. 383263508Sdim bool isInfinity() const { return category == fcInfinity; } 384193323Sed 385263508Sdim /// Returns true if and only if the float is a quiet or signaling NaN. 386263508Sdim bool isNaN() const { return category == fcNaN; } 387193323Sed 388263508Sdim /// Returns true if and only if the float is a signaling NaN. 389263508Sdim bool isSignaling() const; 390193323Sed 391263508Sdim /// @} 392193323Sed 393263508Sdim /// \name Simple Queries 394263508Sdim /// @{ 395193323Sed 396263508Sdim fltCategory getCategory() const { return category; } 397263508Sdim const fltSemantics &getSemantics() const { return *semantics; } 398263508Sdim bool isNonZero() const { return category != fcZero; } 399263508Sdim bool isFiniteNonZero() const { return isFinite() && !isZero(); } 400263508Sdim bool isPosZero() const { return isZero() && !isNegative(); } 401263508Sdim bool isNegZero() const { return isZero() && isNegative(); } 402193323Sed 403263508Sdim /// Returns true if and only if the number has the smallest possible non-zero 404263508Sdim /// magnitude in the current semantics. 405263508Sdim bool isSmallest() const; 406193323Sed 407263508Sdim /// Returns true if and only if the number has the largest possible finite 408263508Sdim /// magnitude in the current semantics. 409263508Sdim bool isLargest() const; 410193323Sed 411263508Sdim /// @} 412193323Sed 413263508Sdim APFloat &operator=(const APFloat &); 414193323Sed 415263508Sdim /// \brief Overload to compute a hash code for an APFloat value. 416263508Sdim /// 417263508Sdim /// Note that the use of hash codes for floating point values is in general 418263508Sdim /// frought with peril. Equality is hard to define for these values. For 419263508Sdim /// example, should negative and positive zero hash to different codes? Are 420263508Sdim /// they equal or not? This hash value implementation specifically 421263508Sdim /// emphasizes producing different codes for different inputs in order to 422263508Sdim /// be used in canonicalization and memoization. As such, equality is 423263508Sdim /// bitwiseIsEqual, and 0 != -0. 424263508Sdim friend hash_code hash_value(const APFloat &Arg); 425193323Sed 426263508Sdim /// Converts this value into a decimal string. 427263508Sdim /// 428263508Sdim /// \param FormatPrecision The maximum number of digits of 429263508Sdim /// precision to output. If there are fewer digits available, 430263508Sdim /// zero padding will not be used unless the value is 431263508Sdim /// integral and small enough to be expressed in 432263508Sdim /// FormatPrecision digits. 0 means to use the natural 433263508Sdim /// precision of the number. 434263508Sdim /// \param FormatMaxPadding The maximum number of zeros to 435263508Sdim /// consider inserting before falling back to scientific 436263508Sdim /// notation. 0 means to always use scientific notation. 437263508Sdim /// 438263508Sdim /// Number Precision MaxPadding Result 439263508Sdim /// ------ --------- ---------- ------ 440263508Sdim /// 1.01E+4 5 2 10100 441263508Sdim /// 1.01E+4 4 2 1.01E+4 442263508Sdim /// 1.01E+4 5 1 1.01E+4 443263508Sdim /// 1.01E-2 5 2 0.0101 444263508Sdim /// 1.01E-2 4 2 0.0101 445263508Sdim /// 1.01E-2 4 1 1.01E-2 446263508Sdim void toString(SmallVectorImpl<char> &Str, unsigned FormatPrecision = 0, 447263508Sdim unsigned FormatMaxPadding = 3) const; 448193323Sed 449263508Sdim /// If this value has an exact multiplicative inverse, store it in inv and 450263508Sdim /// return true. 451263508Sdim bool getExactInverse(APFloat *inv) const; 452193323Sed 453263508Sdimprivate: 454263508Sdim 455263508Sdim /// \name Simple Queries 456263508Sdim /// @{ 457263508Sdim 458263508Sdim integerPart *significandParts(); 459263508Sdim const integerPart *significandParts() const; 460263508Sdim unsigned int partCount() const; 461263508Sdim 462263508Sdim /// @} 463263508Sdim 464263508Sdim /// \name Significand operations. 465263508Sdim /// @{ 466263508Sdim 467263508Sdim integerPart addSignificand(const APFloat &); 468263508Sdim integerPart subtractSignificand(const APFloat &, integerPart); 469263508Sdim lostFraction addOrSubtractSignificand(const APFloat &, bool subtract); 470263508Sdim lostFraction multiplySignificand(const APFloat &, const APFloat *); 471263508Sdim lostFraction divideSignificand(const APFloat &); 472263508Sdim void incrementSignificand(); 473263508Sdim void initialize(const fltSemantics *); 474263508Sdim void shiftSignificandLeft(unsigned int); 475263508Sdim lostFraction shiftSignificandRight(unsigned int); 476263508Sdim unsigned int significandLSB() const; 477263508Sdim unsigned int significandMSB() const; 478263508Sdim void zeroSignificand(); 479263508Sdim /// Return true if the significand excluding the integral bit is all ones. 480263508Sdim bool isSignificandAllOnes() const; 481263508Sdim /// Return true if the significand excluding the integral bit is all zeros. 482263508Sdim bool isSignificandAllZeros() const; 483263508Sdim 484263508Sdim /// @} 485263508Sdim 486263508Sdim /// \name Arithmetic on special values. 487263508Sdim /// @{ 488263508Sdim 489263508Sdim opStatus addOrSubtractSpecials(const APFloat &, bool subtract); 490263508Sdim opStatus divideSpecials(const APFloat &); 491263508Sdim opStatus multiplySpecials(const APFloat &); 492263508Sdim opStatus modSpecials(const APFloat &); 493263508Sdim 494263508Sdim /// @} 495263508Sdim 496263508Sdim /// \name Special value setters. 497263508Sdim /// @{ 498263508Sdim 499263508Sdim void makeLargest(bool Neg = false); 500263508Sdim void makeSmallest(bool Neg = false); 501263508Sdim void makeNaN(bool SNaN = false, bool Neg = false, const APInt *fill = 0); 502263508Sdim static APFloat makeNaN(const fltSemantics &Sem, bool SNaN, bool Negative, 503263508Sdim const APInt *fill); 504263508Sdim void makeInf(bool Neg = false); 505263508Sdim void makeZero(bool Neg = false); 506263508Sdim 507263508Sdim /// @} 508263508Sdim 509263508Sdim /// \name Miscellany 510263508Sdim /// @{ 511263508Sdim 512263508Sdim bool convertFromStringSpecials(StringRef str); 513263508Sdim opStatus normalize(roundingMode, lostFraction); 514263508Sdim opStatus addOrSubtract(const APFloat &, roundingMode, bool subtract); 515263508Sdim cmpResult compareAbsoluteValue(const APFloat &) const; 516263508Sdim opStatus handleOverflow(roundingMode); 517263508Sdim bool roundAwayFromZero(roundingMode, lostFraction, unsigned int) const; 518263508Sdim opStatus convertToSignExtendedInteger(integerPart *, unsigned int, bool, 519263508Sdim roundingMode, bool *) const; 520263508Sdim opStatus convertFromUnsignedParts(const integerPart *, unsigned int, 521263508Sdim roundingMode); 522263508Sdim opStatus convertFromHexadecimalString(StringRef, roundingMode); 523263508Sdim opStatus convertFromDecimalString(StringRef, roundingMode); 524263508Sdim char *convertNormalToHexString(char *, unsigned int, bool, 525263508Sdim roundingMode) const; 526263508Sdim opStatus roundSignificandWithExponent(const integerPart *, unsigned int, int, 527263508Sdim roundingMode); 528263508Sdim 529263508Sdim /// @} 530263508Sdim 531263508Sdim APInt convertHalfAPFloatToAPInt() const; 532263508Sdim APInt convertFloatAPFloatToAPInt() const; 533263508Sdim APInt convertDoubleAPFloatToAPInt() const; 534263508Sdim APInt convertQuadrupleAPFloatToAPInt() const; 535263508Sdim APInt convertF80LongDoubleAPFloatToAPInt() const; 536263508Sdim APInt convertPPCDoubleDoubleAPFloatToAPInt() const; 537263508Sdim void initFromAPInt(const fltSemantics *Sem, const APInt &api); 538263508Sdim void initFromHalfAPInt(const APInt &api); 539263508Sdim void initFromFloatAPInt(const APInt &api); 540263508Sdim void initFromDoubleAPInt(const APInt &api); 541263508Sdim void initFromQuadrupleAPInt(const APInt &api); 542263508Sdim void initFromF80LongDoubleAPInt(const APInt &api); 543263508Sdim void initFromPPCDoubleDoubleAPInt(const APInt &api); 544263508Sdim 545263508Sdim void assign(const APFloat &); 546263508Sdim void copySignificand(const APFloat &); 547263508Sdim void freeSignificand(); 548263508Sdim 549263508Sdim /// The semantics that this value obeys. 550263508Sdim const fltSemantics *semantics; 551263508Sdim 552263508Sdim /// A binary fraction with an explicit integer bit. 553263508Sdim /// 554263508Sdim /// The significand must be at least one bit wider than the target precision. 555263508Sdim union Significand { 556263508Sdim integerPart part; 557263508Sdim integerPart *parts; 558263508Sdim } significand; 559263508Sdim 560263508Sdim /// The signed unbiased exponent of the value. 561263508Sdim ExponentType exponent; 562263508Sdim 563263508Sdim /// What kind of floating point number this is. 564263508Sdim /// 565263508Sdim /// Only 2 bits are required, but VisualStudio incorrectly sign extends it. 566263508Sdim /// Using the extra bit keeps it from failing under VisualStudio. 567263508Sdim fltCategory category : 3; 568263508Sdim 569263508Sdim /// Sign bit of the number. 570263508Sdim unsigned int sign : 1; 571263508Sdim}; 572263508Sdim 573263508Sdim/// See friend declaration above. 574263508Sdim/// 575263508Sdim/// This additional declaration is required in order to compile LLVM with IBM 576263508Sdim/// xlC compiler. 577263508Sdimhash_code hash_value(const APFloat &Arg); 578263508Sdim} // namespace llvm 579263508Sdim 580263508Sdim#endif // LLVM_ADT_APFLOAT_H 581