[SLP] limit vectorization of Constant subclasses (PR33958)
[llvm-core.git] / include / llvm / ADT / APFloat.h
blob1c4969733791d9221771c826eb37f47e5f1f6f9e
1 //===- llvm/ADT/APFloat.h - Arbitrary Precision Floating Point ---*- C++ -*-==//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// \brief
11 /// This file declares a class to represent arbitrary precision floating point
12 /// values and provide a variety of arithmetic operations on them.
13 ///
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_ADT_APFLOAT_H
17 #define LLVM_ADT_APFLOAT_H
19 #include "llvm/ADT/APInt.h"
20 #include "llvm/ADT/ArrayRef.h"
21 #include "llvm/Support/ErrorHandling.h"
22 #include <memory>
24 #define APFLOAT_DISPATCH_ON_SEMANTICS(METHOD_CALL) \
25 do { \
26 if (usesLayout<IEEEFloat>(getSemantics())) \
27 return U.IEEE.METHOD_CALL; \
28 if (usesLayout<DoubleAPFloat>(getSemantics())) \
29 return U.Double.METHOD_CALL; \
30 llvm_unreachable("Unexpected semantics"); \
31 } while (false)
33 namespace llvm {
35 struct fltSemantics;
36 class APSInt;
37 class StringRef;
38 class APFloat;
39 class raw_ostream;
41 template <typename T> class SmallVectorImpl;
43 /// Enum that represents what fraction of the LSB truncated bits of an fp number
44 /// represent.
45 ///
46 /// This essentially combines the roles of guard and sticky bits.
47 enum lostFraction { // Example of truncated bits:
48 lfExactlyZero, // 000000
49 lfLessThanHalf, // 0xxxxx x's not all zero
50 lfExactlyHalf, // 100000
51 lfMoreThanHalf // 1xxxxx x's not all zero
54 /// A self-contained host- and target-independent arbitrary-precision
55 /// floating-point software implementation.
56 ///
57 /// APFloat uses bignum integer arithmetic as provided by static functions in
58 /// the APInt class. The library will work with bignum integers whose parts are
59 /// any unsigned type at least 16 bits wide, but 64 bits is recommended.
60 ///
61 /// Written for clarity rather than speed, in particular with a view to use in
62 /// the front-end of a cross compiler so that target arithmetic can be correctly
63 /// performed on the host. Performance should nonetheless be reasonable,
64 /// particularly for its intended use. It may be useful as a base
65 /// implementation for a run-time library during development of a faster
66 /// target-specific one.
67 ///
68 /// All 5 rounding modes in the IEEE-754R draft are handled correctly for all
69 /// implemented operations. Currently implemented operations are add, subtract,
70 /// multiply, divide, fused-multiply-add, conversion-to-float,
71 /// conversion-to-integer and conversion-from-integer. New rounding modes
72 /// (e.g. away from zero) can be added with three or four lines of code.
73 ///
74 /// Four formats are built-in: IEEE single precision, double precision,
75 /// quadruple precision, and x87 80-bit extended double (when operating with
76 /// full extended precision). Adding a new format that obeys IEEE semantics
77 /// only requires adding two lines of code: a declaration and definition of the
78 /// format.
79 ///
80 /// All operations return the status of that operation as an exception bit-mask,
81 /// so multiple operations can be done consecutively with their results or-ed
82 /// together. The returned status can be useful for compiler diagnostics; e.g.,
83 /// inexact, underflow and overflow can be easily diagnosed on constant folding,
84 /// and compiler optimizers can determine what exceptions would be raised by
85 /// folding operations and optimize, or perhaps not optimize, accordingly.
86 ///
87 /// At present, underflow tininess is detected after rounding; it should be
88 /// straight forward to add support for the before-rounding case too.
89 ///
90 /// The library reads hexadecimal floating point numbers as per C99, and
91 /// correctly rounds if necessary according to the specified rounding mode.
92 /// Syntax is required to have been validated by the caller. It also converts
93 /// floating point numbers to hexadecimal text as per the C99 %a and %A
94 /// conversions. The output precision (or alternatively the natural minimal
95 /// precision) can be specified; if the requested precision is less than the
96 /// natural precision the output is correctly rounded for the specified rounding
97 /// mode.
98 ///
99 /// It also reads decimal floating point numbers and correctly rounds according
100 /// to the specified rounding mode.
102 /// Conversion to decimal text is not currently implemented.
104 /// Non-zero finite numbers are represented internally as a sign bit, a 16-bit
105 /// signed exponent, and the significand as an array of integer parts. After
106 /// normalization of a number of precision P the exponent is within the range of
107 /// the format, and if the number is not denormal the P-th bit of the
108 /// significand is set as an explicit integer bit. For denormals the most
109 /// significant bit is shifted right so that the exponent is maintained at the
110 /// format's minimum, so that the smallest denormal has just the least
111 /// significant bit of the significand set. The sign of zeroes and infinities
112 /// is significant; the exponent and significand of such numbers is not stored,
113 /// but has a known implicit (deterministic) value: 0 for the significands, 0
114 /// for zero exponent, all 1 bits for infinity exponent. For NaNs the sign and
115 /// significand are deterministic, although not really meaningful, and preserved
116 /// in non-conversion operations. The exponent is implicitly all 1 bits.
118 /// APFloat does not provide any exception handling beyond default exception
119 /// handling. We represent Signaling NaNs via IEEE-754R 2008 6.2.1 should clause
120 /// by encoding Signaling NaNs with the first bit of its trailing significand as
121 /// 0.
123 /// TODO
124 /// ====
126 /// Some features that may or may not be worth adding:
128 /// Binary to decimal conversion (hard).
130 /// Optional ability to detect underflow tininess before rounding.
132 /// New formats: x87 in single and double precision mode (IEEE apart from
133 /// extended exponent range) (hard).
135 /// New operations: sqrt, IEEE remainder, C90 fmod, nexttoward.
138 // This is the common type definitions shared by APFloat and its internal
139 // implementation classes. This struct should not define any non-static data
140 // members.
141 struct APFloatBase {
142 typedef APInt::WordType integerPart;
143 static const unsigned integerPartWidth = APInt::APINT_BITS_PER_WORD;
145 /// A signed type to represent a floating point numbers unbiased exponent.
146 typedef signed short ExponentType;
148 /// \name Floating Point Semantics.
149 /// @{
150 enum Semantics {
151 S_IEEEhalf,
152 S_IEEEsingle,
153 S_IEEEdouble,
154 S_x87DoubleExtended,
155 S_IEEEquad,
156 S_PPCDoubleDouble
159 static const llvm::fltSemantics &EnumToSemantics(Semantics S);
160 static Semantics SemanticsToEnum(const llvm::fltSemantics &Sem);
162 static const fltSemantics &IEEEhalf() LLVM_READNONE;
163 static const fltSemantics &IEEEsingle() LLVM_READNONE;
164 static const fltSemantics &IEEEdouble() LLVM_READNONE;
165 static const fltSemantics &IEEEquad() LLVM_READNONE;
166 static const fltSemantics &PPCDoubleDouble() LLVM_READNONE;
167 static const fltSemantics &x87DoubleExtended() LLVM_READNONE;
169 /// A Pseudo fltsemantic used to construct APFloats that cannot conflict with
170 /// anything real.
171 static const fltSemantics &Bogus() LLVM_READNONE;
173 /// @}
175 /// IEEE-754R 5.11: Floating Point Comparison Relations.
176 enum cmpResult {
177 cmpLessThan,
178 cmpEqual,
179 cmpGreaterThan,
180 cmpUnordered
183 /// IEEE-754R 4.3: Rounding-direction attributes.
184 enum roundingMode {
185 rmNearestTiesToEven,
186 rmTowardPositive,
187 rmTowardNegative,
188 rmTowardZero,
189 rmNearestTiesToAway
192 /// IEEE-754R 7: Default exception handling.
194 /// opUnderflow or opOverflow are always returned or-ed with opInexact.
196 /// APFloat models this behavior specified by IEEE-754:
197 /// "For operations producing results in floating-point format, the default
198 /// result of an operation that signals the invalid operation exception
199 /// shall be a quiet NaN."
200 enum opStatus {
201 opOK = 0x00,
202 opInvalidOp = 0x01,
203 opDivByZero = 0x02,
204 opOverflow = 0x04,
205 opUnderflow = 0x08,
206 opInexact = 0x10
209 /// Category of internally-represented number.
210 enum fltCategory {
211 fcInfinity,
212 fcNaN,
213 fcNormal,
214 fcZero
217 /// Convenience enum used to construct an uninitialized APFloat.
218 enum uninitializedTag {
219 uninitialized
222 /// Enumeration of \c ilogb error results.
223 enum IlogbErrorKinds {
224 IEK_Zero = INT_MIN + 1,
225 IEK_NaN = INT_MIN,
226 IEK_Inf = INT_MAX
229 static unsigned int semanticsPrecision(const fltSemantics &);
230 static ExponentType semanticsMinExponent(const fltSemantics &);
231 static ExponentType semanticsMaxExponent(const fltSemantics &);
232 static unsigned int semanticsSizeInBits(const fltSemantics &);
234 /// Returns the size of the floating point number (in bits) in the given
235 /// semantics.
236 static unsigned getSizeInBits(const fltSemantics &Sem);
239 namespace detail {
241 class IEEEFloat final : public APFloatBase {
242 public:
243 /// \name Constructors
244 /// @{
246 IEEEFloat(const fltSemantics &); // Default construct to 0.0
247 IEEEFloat(const fltSemantics &, integerPart);
248 IEEEFloat(const fltSemantics &, uninitializedTag);
249 IEEEFloat(const fltSemantics &, const APInt &);
250 explicit IEEEFloat(double d);
251 explicit IEEEFloat(float f);
252 IEEEFloat(const IEEEFloat &);
253 IEEEFloat(IEEEFloat &&);
254 ~IEEEFloat();
256 /// @}
258 /// Returns whether this instance allocated memory.
259 bool needsCleanup() const { return partCount() > 1; }
261 /// \name Convenience "constructors"
262 /// @{
264 /// @}
266 /// \name Arithmetic
267 /// @{
269 opStatus add(const IEEEFloat &, roundingMode);
270 opStatus subtract(const IEEEFloat &, roundingMode);
271 opStatus multiply(const IEEEFloat &, roundingMode);
272 opStatus divide(const IEEEFloat &, roundingMode);
273 /// IEEE remainder.
274 opStatus remainder(const IEEEFloat &);
275 /// C fmod, or llvm frem.
276 opStatus mod(const IEEEFloat &);
277 opStatus fusedMultiplyAdd(const IEEEFloat &, const IEEEFloat &, roundingMode);
278 opStatus roundToIntegral(roundingMode);
279 /// IEEE-754R 5.3.1: nextUp/nextDown.
280 opStatus next(bool nextDown);
282 /// @}
284 /// \name Sign operations.
285 /// @{
287 void changeSign();
289 /// @}
291 /// \name Conversions
292 /// @{
294 opStatus convert(const fltSemantics &, roundingMode, bool *);
295 opStatus convertToInteger(MutableArrayRef<integerPart>, unsigned int, bool,
296 roundingMode, bool *) const;
297 opStatus convertFromAPInt(const APInt &, bool, roundingMode);
298 opStatus convertFromSignExtendedInteger(const integerPart *, unsigned int,
299 bool, roundingMode);
300 opStatus convertFromZeroExtendedInteger(const integerPart *, unsigned int,
301 bool, roundingMode);
302 opStatus convertFromString(StringRef, roundingMode);
303 APInt bitcastToAPInt() const;
304 double convertToDouble() const;
305 float convertToFloat() const;
307 /// @}
309 /// The definition of equality is not straightforward for floating point, so
310 /// we won't use operator==. Use one of the following, or write whatever it
311 /// is you really mean.
312 bool operator==(const IEEEFloat &) const = delete;
314 /// IEEE comparison with another floating point number (NaNs compare
315 /// unordered, 0==-0).
316 cmpResult compare(const IEEEFloat &) const;
318 /// Bitwise comparison for equality (QNaNs compare equal, 0!=-0).
319 bool bitwiseIsEqual(const IEEEFloat &) const;
321 /// Write out a hexadecimal representation of the floating point value to DST,
322 /// which must be of sufficient size, in the C99 form [-]0xh.hhhhp[+-]d.
323 /// Return the number of characters written, excluding the terminating NUL.
324 unsigned int convertToHexString(char *dst, unsigned int hexDigits,
325 bool upperCase, roundingMode) const;
327 /// \name IEEE-754R 5.7.2 General operations.
328 /// @{
330 /// IEEE-754R isSignMinus: Returns true if and only if the current value is
331 /// negative.
333 /// This applies to zeros and NaNs as well.
334 bool isNegative() const { return sign; }
336 /// IEEE-754R isNormal: Returns true if and only if the current value is normal.
338 /// This implies that the current value of the float is not zero, subnormal,
339 /// infinite, or NaN following the definition of normality from IEEE-754R.
340 bool isNormal() const { return !isDenormal() && isFiniteNonZero(); }
342 /// Returns true if and only if the current value is zero, subnormal, or
343 /// normal.
345 /// This means that the value is not infinite or NaN.
346 bool isFinite() const { return !isNaN() && !isInfinity(); }
348 /// Returns true if and only if the float is plus or minus zero.
349 bool isZero() const { return category == fcZero; }
351 /// IEEE-754R isSubnormal(): Returns true if and only if the float is a
352 /// denormal.
353 bool isDenormal() const;
355 /// IEEE-754R isInfinite(): Returns true if and only if the float is infinity.
356 bool isInfinity() const { return category == fcInfinity; }
358 /// Returns true if and only if the float is a quiet or signaling NaN.
359 bool isNaN() const { return category == fcNaN; }
361 /// Returns true if and only if the float is a signaling NaN.
362 bool isSignaling() const;
364 /// @}
366 /// \name Simple Queries
367 /// @{
369 fltCategory getCategory() const { return category; }
370 const fltSemantics &getSemantics() const { return *semantics; }
371 bool isNonZero() const { return category != fcZero; }
372 bool isFiniteNonZero() const { return isFinite() && !isZero(); }
373 bool isPosZero() const { return isZero() && !isNegative(); }
374 bool isNegZero() const { return isZero() && isNegative(); }
376 /// Returns true if and only if the number has the smallest possible non-zero
377 /// magnitude in the current semantics.
378 bool isSmallest() const;
380 /// Returns true if and only if the number has the largest possible finite
381 /// magnitude in the current semantics.
382 bool isLargest() const;
384 /// Returns true if and only if the number is an exact integer.
385 bool isInteger() const;
387 /// @}
389 IEEEFloat &operator=(const IEEEFloat &);
390 IEEEFloat &operator=(IEEEFloat &&);
392 /// Overload to compute a hash code for an APFloat value.
394 /// Note that the use of hash codes for floating point values is in general
395 /// frought with peril. Equality is hard to define for these values. For
396 /// example, should negative and positive zero hash to different codes? Are
397 /// they equal or not? This hash value implementation specifically
398 /// emphasizes producing different codes for different inputs in order to
399 /// be used in canonicalization and memoization. As such, equality is
400 /// bitwiseIsEqual, and 0 != -0.
401 friend hash_code hash_value(const IEEEFloat &Arg);
403 /// Converts this value into a decimal string.
405 /// \param FormatPrecision The maximum number of digits of
406 /// precision to output. If there are fewer digits available,
407 /// zero padding will not be used unless the value is
408 /// integral and small enough to be expressed in
409 /// FormatPrecision digits. 0 means to use the natural
410 /// precision of the number.
411 /// \param FormatMaxPadding The maximum number of zeros to
412 /// consider inserting before falling back to scientific
413 /// notation. 0 means to always use scientific notation.
415 /// \param TruncateZero Indicate whether to remove the trailing zero in
416 /// fraction part or not. Also setting this parameter to false forcing
417 /// producing of output more similar to default printf behavior.
418 /// Specifically the lower e is used as exponent delimiter and exponent
419 /// always contains no less than two digits.
421 /// Number Precision MaxPadding Result
422 /// ------ --------- ---------- ------
423 /// 1.01E+4 5 2 10100
424 /// 1.01E+4 4 2 1.01E+4
425 /// 1.01E+4 5 1 1.01E+4
426 /// 1.01E-2 5 2 0.0101
427 /// 1.01E-2 4 2 0.0101
428 /// 1.01E-2 4 1 1.01E-2
429 void toString(SmallVectorImpl<char> &Str, unsigned FormatPrecision = 0,
430 unsigned FormatMaxPadding = 3, bool TruncateZero = true) const;
432 /// If this value has an exact multiplicative inverse, store it in inv and
433 /// return true.
434 bool getExactInverse(APFloat *inv) const;
436 /// Returns the exponent of the internal representation of the APFloat.
438 /// Because the radix of APFloat is 2, this is equivalent to floor(log2(x)).
439 /// For special APFloat values, this returns special error codes:
441 /// NaN -> \c IEK_NaN
442 /// 0 -> \c IEK_Zero
443 /// Inf -> \c IEK_Inf
445 friend int ilogb(const IEEEFloat &Arg);
447 /// Returns: X * 2^Exp for integral exponents.
448 friend IEEEFloat scalbn(IEEEFloat X, int Exp, roundingMode);
450 friend IEEEFloat frexp(const IEEEFloat &X, int &Exp, roundingMode);
452 /// \name Special value setters.
453 /// @{
455 void makeLargest(bool Neg = false);
456 void makeSmallest(bool Neg = false);
457 void makeNaN(bool SNaN = false, bool Neg = false,
458 const APInt *fill = nullptr);
459 void makeInf(bool Neg = false);
460 void makeZero(bool Neg = false);
461 void makeQuiet();
463 /// Returns the smallest (by magnitude) normalized finite number in the given
464 /// semantics.
466 /// \param Negative - True iff the number should be negative
467 void makeSmallestNormalized(bool Negative = false);
469 /// @}
471 cmpResult compareAbsoluteValue(const IEEEFloat &) const;
473 private:
474 /// \name Simple Queries
475 /// @{
477 integerPart *significandParts();
478 const integerPart *significandParts() const;
479 unsigned int partCount() const;
481 /// @}
483 /// \name Significand operations.
484 /// @{
486 integerPart addSignificand(const IEEEFloat &);
487 integerPart subtractSignificand(const IEEEFloat &, integerPart);
488 lostFraction addOrSubtractSignificand(const IEEEFloat &, bool subtract);
489 lostFraction multiplySignificand(const IEEEFloat &, const IEEEFloat *);
490 lostFraction divideSignificand(const IEEEFloat &);
491 void incrementSignificand();
492 void initialize(const fltSemantics *);
493 void shiftSignificandLeft(unsigned int);
494 lostFraction shiftSignificandRight(unsigned int);
495 unsigned int significandLSB() const;
496 unsigned int significandMSB() const;
497 void zeroSignificand();
498 /// Return true if the significand excluding the integral bit is all ones.
499 bool isSignificandAllOnes() const;
500 /// Return true if the significand excluding the integral bit is all zeros.
501 bool isSignificandAllZeros() const;
503 /// @}
505 /// \name Arithmetic on special values.
506 /// @{
508 opStatus addOrSubtractSpecials(const IEEEFloat &, bool subtract);
509 opStatus divideSpecials(const IEEEFloat &);
510 opStatus multiplySpecials(const IEEEFloat &);
511 opStatus modSpecials(const IEEEFloat &);
513 /// @}
515 /// \name Miscellany
516 /// @{
518 bool convertFromStringSpecials(StringRef str);
519 opStatus normalize(roundingMode, lostFraction);
520 opStatus addOrSubtract(const IEEEFloat &, roundingMode, bool subtract);
521 opStatus handleOverflow(roundingMode);
522 bool roundAwayFromZero(roundingMode, lostFraction, unsigned int) const;
523 opStatus convertToSignExtendedInteger(MutableArrayRef<integerPart>,
524 unsigned int, bool, roundingMode,
525 bool *) const;
526 opStatus convertFromUnsignedParts(const integerPart *, unsigned int,
527 roundingMode);
528 opStatus convertFromHexadecimalString(StringRef, roundingMode);
529 opStatus convertFromDecimalString(StringRef, roundingMode);
530 char *convertNormalToHexString(char *, unsigned int, bool,
531 roundingMode) const;
532 opStatus roundSignificandWithExponent(const integerPart *, unsigned int, int,
533 roundingMode);
535 /// @}
537 APInt convertHalfAPFloatToAPInt() const;
538 APInt convertFloatAPFloatToAPInt() const;
539 APInt convertDoubleAPFloatToAPInt() const;
540 APInt convertQuadrupleAPFloatToAPInt() const;
541 APInt convertF80LongDoubleAPFloatToAPInt() const;
542 APInt convertPPCDoubleDoubleAPFloatToAPInt() const;
543 void initFromAPInt(const fltSemantics *Sem, const APInt &api);
544 void initFromHalfAPInt(const APInt &api);
545 void initFromFloatAPInt(const APInt &api);
546 void initFromDoubleAPInt(const APInt &api);
547 void initFromQuadrupleAPInt(const APInt &api);
548 void initFromF80LongDoubleAPInt(const APInt &api);
549 void initFromPPCDoubleDoubleAPInt(const APInt &api);
551 void assign(const IEEEFloat &);
552 void copySignificand(const IEEEFloat &);
553 void freeSignificand();
555 /// Note: this must be the first data member.
556 /// The semantics that this value obeys.
557 const fltSemantics *semantics;
559 /// A binary fraction with an explicit integer bit.
561 /// The significand must be at least one bit wider than the target precision.
562 union Significand {
563 integerPart part;
564 integerPart *parts;
565 } significand;
567 /// The signed unbiased exponent of the value.
568 ExponentType exponent;
570 /// What kind of floating point number this is.
572 /// Only 2 bits are required, but VisualStudio incorrectly sign extends it.
573 /// Using the extra bit keeps it from failing under VisualStudio.
574 fltCategory category : 3;
576 /// Sign bit of the number.
577 unsigned int sign : 1;
580 hash_code hash_value(const IEEEFloat &Arg);
581 int ilogb(const IEEEFloat &Arg);
582 IEEEFloat scalbn(IEEEFloat X, int Exp, IEEEFloat::roundingMode);
583 IEEEFloat frexp(const IEEEFloat &Val, int &Exp, IEEEFloat::roundingMode RM);
585 // This mode implements more precise float in terms of two APFloats.
586 // The interface and layout is designed for arbitray underlying semantics,
587 // though currently only PPCDoubleDouble semantics are supported, whose
588 // corresponding underlying semantics are IEEEdouble.
589 class DoubleAPFloat final : public APFloatBase {
590 // Note: this must be the first data member.
591 const fltSemantics *Semantics;
592 std::unique_ptr<APFloat[]> Floats;
594 opStatus addImpl(const APFloat &a, const APFloat &aa, const APFloat &c,
595 const APFloat &cc, roundingMode RM);
597 opStatus addWithSpecial(const DoubleAPFloat &LHS, const DoubleAPFloat &RHS,
598 DoubleAPFloat &Out, roundingMode RM);
600 public:
601 DoubleAPFloat(const fltSemantics &S);
602 DoubleAPFloat(const fltSemantics &S, uninitializedTag);
603 DoubleAPFloat(const fltSemantics &S, integerPart);
604 DoubleAPFloat(const fltSemantics &S, const APInt &I);
605 DoubleAPFloat(const fltSemantics &S, APFloat &&First, APFloat &&Second);
606 DoubleAPFloat(const DoubleAPFloat &RHS);
607 DoubleAPFloat(DoubleAPFloat &&RHS);
609 DoubleAPFloat &operator=(const DoubleAPFloat &RHS);
611 DoubleAPFloat &operator=(DoubleAPFloat &&RHS) {
612 if (this != &RHS) {
613 this->~DoubleAPFloat();
614 new (this) DoubleAPFloat(std::move(RHS));
616 return *this;
619 bool needsCleanup() const { return Floats != nullptr; }
621 APFloat &getFirst() { return Floats[0]; }
622 const APFloat &getFirst() const { return Floats[0]; }
623 APFloat &getSecond() { return Floats[1]; }
624 const APFloat &getSecond() const { return Floats[1]; }
626 opStatus add(const DoubleAPFloat &RHS, roundingMode RM);
627 opStatus subtract(const DoubleAPFloat &RHS, roundingMode RM);
628 opStatus multiply(const DoubleAPFloat &RHS, roundingMode RM);
629 opStatus divide(const DoubleAPFloat &RHS, roundingMode RM);
630 opStatus remainder(const DoubleAPFloat &RHS);
631 opStatus mod(const DoubleAPFloat &RHS);
632 opStatus fusedMultiplyAdd(const DoubleAPFloat &Multiplicand,
633 const DoubleAPFloat &Addend, roundingMode RM);
634 opStatus roundToIntegral(roundingMode RM);
635 void changeSign();
636 cmpResult compareAbsoluteValue(const DoubleAPFloat &RHS) const;
638 fltCategory getCategory() const;
639 bool isNegative() const;
641 void makeInf(bool Neg);
642 void makeZero(bool Neg);
643 void makeLargest(bool Neg);
644 void makeSmallest(bool Neg);
645 void makeSmallestNormalized(bool Neg);
646 void makeNaN(bool SNaN, bool Neg, const APInt *fill);
648 cmpResult compare(const DoubleAPFloat &RHS) const;
649 bool bitwiseIsEqual(const DoubleAPFloat &RHS) const;
650 APInt bitcastToAPInt() const;
651 opStatus convertFromString(StringRef, roundingMode);
652 opStatus next(bool nextDown);
654 opStatus convertToInteger(MutableArrayRef<integerPart> Input,
655 unsigned int Width, bool IsSigned, roundingMode RM,
656 bool *IsExact) const;
657 opStatus convertFromAPInt(const APInt &Input, bool IsSigned, roundingMode RM);
658 opStatus convertFromSignExtendedInteger(const integerPart *Input,
659 unsigned int InputSize, bool IsSigned,
660 roundingMode RM);
661 opStatus convertFromZeroExtendedInteger(const integerPart *Input,
662 unsigned int InputSize, bool IsSigned,
663 roundingMode RM);
664 unsigned int convertToHexString(char *DST, unsigned int HexDigits,
665 bool UpperCase, roundingMode RM) const;
667 bool isDenormal() const;
668 bool isSmallest() const;
669 bool isLargest() const;
670 bool isInteger() const;
672 void toString(SmallVectorImpl<char> &Str, unsigned FormatPrecision,
673 unsigned FormatMaxPadding, bool TruncateZero = true) const;
675 bool getExactInverse(APFloat *inv) const;
677 friend int ilogb(const DoubleAPFloat &Arg);
678 friend DoubleAPFloat scalbn(DoubleAPFloat X, int Exp, roundingMode);
679 friend DoubleAPFloat frexp(const DoubleAPFloat &X, int &Exp, roundingMode);
680 friend hash_code hash_value(const DoubleAPFloat &Arg);
683 hash_code hash_value(const DoubleAPFloat &Arg);
685 } // End detail namespace
687 // This is a interface class that is currently forwarding functionalities from
688 // detail::IEEEFloat.
689 class APFloat : public APFloatBase {
690 typedef detail::IEEEFloat IEEEFloat;
691 typedef detail::DoubleAPFloat DoubleAPFloat;
693 static_assert(std::is_standard_layout<IEEEFloat>::value, "");
695 union Storage {
696 const fltSemantics *semantics;
697 IEEEFloat IEEE;
698 DoubleAPFloat Double;
700 explicit Storage(IEEEFloat F, const fltSemantics &S);
701 explicit Storage(DoubleAPFloat F, const fltSemantics &S)
702 : Double(std::move(F)) {
703 assert(&S == &PPCDoubleDouble());
706 template <typename... ArgTypes>
707 Storage(const fltSemantics &Semantics, ArgTypes &&... Args) {
708 if (usesLayout<IEEEFloat>(Semantics)) {
709 new (&IEEE) IEEEFloat(Semantics, std::forward<ArgTypes>(Args)...);
710 return;
712 if (usesLayout<DoubleAPFloat>(Semantics)) {
713 new (&Double) DoubleAPFloat(Semantics, std::forward<ArgTypes>(Args)...);
714 return;
716 llvm_unreachable("Unexpected semantics");
719 ~Storage() {
720 if (usesLayout<IEEEFloat>(*semantics)) {
721 IEEE.~IEEEFloat();
722 return;
724 if (usesLayout<DoubleAPFloat>(*semantics)) {
725 Double.~DoubleAPFloat();
726 return;
728 llvm_unreachable("Unexpected semantics");
731 Storage(const Storage &RHS) {
732 if (usesLayout<IEEEFloat>(*RHS.semantics)) {
733 new (this) IEEEFloat(RHS.IEEE);
734 return;
736 if (usesLayout<DoubleAPFloat>(*RHS.semantics)) {
737 new (this) DoubleAPFloat(RHS.Double);
738 return;
740 llvm_unreachable("Unexpected semantics");
743 Storage(Storage &&RHS) {
744 if (usesLayout<IEEEFloat>(*RHS.semantics)) {
745 new (this) IEEEFloat(std::move(RHS.IEEE));
746 return;
748 if (usesLayout<DoubleAPFloat>(*RHS.semantics)) {
749 new (this) DoubleAPFloat(std::move(RHS.Double));
750 return;
752 llvm_unreachable("Unexpected semantics");
755 Storage &operator=(const Storage &RHS) {
756 if (usesLayout<IEEEFloat>(*semantics) &&
757 usesLayout<IEEEFloat>(*RHS.semantics)) {
758 IEEE = RHS.IEEE;
759 } else if (usesLayout<DoubleAPFloat>(*semantics) &&
760 usesLayout<DoubleAPFloat>(*RHS.semantics)) {
761 Double = RHS.Double;
762 } else if (this != &RHS) {
763 this->~Storage();
764 new (this) Storage(RHS);
766 return *this;
769 Storage &operator=(Storage &&RHS) {
770 if (usesLayout<IEEEFloat>(*semantics) &&
771 usesLayout<IEEEFloat>(*RHS.semantics)) {
772 IEEE = std::move(RHS.IEEE);
773 } else if (usesLayout<DoubleAPFloat>(*semantics) &&
774 usesLayout<DoubleAPFloat>(*RHS.semantics)) {
775 Double = std::move(RHS.Double);
776 } else if (this != &RHS) {
777 this->~Storage();
778 new (this) Storage(std::move(RHS));
780 return *this;
782 } U;
784 template <typename T> static bool usesLayout(const fltSemantics &Semantics) {
785 static_assert(std::is_same<T, IEEEFloat>::value ||
786 std::is_same<T, DoubleAPFloat>::value, "");
787 if (std::is_same<T, DoubleAPFloat>::value) {
788 return &Semantics == &PPCDoubleDouble();
790 return &Semantics != &PPCDoubleDouble();
793 IEEEFloat &getIEEE() {
794 if (usesLayout<IEEEFloat>(*U.semantics))
795 return U.IEEE;
796 if (usesLayout<DoubleAPFloat>(*U.semantics))
797 return U.Double.getFirst().U.IEEE;
798 llvm_unreachable("Unexpected semantics");
801 const IEEEFloat &getIEEE() const {
802 if (usesLayout<IEEEFloat>(*U.semantics))
803 return U.IEEE;
804 if (usesLayout<DoubleAPFloat>(*U.semantics))
805 return U.Double.getFirst().U.IEEE;
806 llvm_unreachable("Unexpected semantics");
809 void makeZero(bool Neg) { APFLOAT_DISPATCH_ON_SEMANTICS(makeZero(Neg)); }
811 void makeInf(bool Neg) { APFLOAT_DISPATCH_ON_SEMANTICS(makeInf(Neg)); }
813 void makeNaN(bool SNaN, bool Neg, const APInt *fill) {
814 APFLOAT_DISPATCH_ON_SEMANTICS(makeNaN(SNaN, Neg, fill));
817 void makeLargest(bool Neg) {
818 APFLOAT_DISPATCH_ON_SEMANTICS(makeLargest(Neg));
821 void makeSmallest(bool Neg) {
822 APFLOAT_DISPATCH_ON_SEMANTICS(makeSmallest(Neg));
825 void makeSmallestNormalized(bool Neg) {
826 APFLOAT_DISPATCH_ON_SEMANTICS(makeSmallestNormalized(Neg));
829 // FIXME: This is due to clang 3.3 (or older version) always checks for the
830 // default constructor in an array aggregate initialization, even if no
831 // elements in the array is default initialized.
832 APFloat() : U(IEEEdouble()) {
833 llvm_unreachable("This is a workaround for old clang.");
836 explicit APFloat(IEEEFloat F, const fltSemantics &S) : U(std::move(F), S) {}
837 explicit APFloat(DoubleAPFloat F, const fltSemantics &S)
838 : U(std::move(F), S) {}
840 cmpResult compareAbsoluteValue(const APFloat &RHS) const {
841 assert(&getSemantics() == &RHS.getSemantics() &&
842 "Should only compare APFloats with the same semantics");
843 if (usesLayout<IEEEFloat>(getSemantics()))
844 return U.IEEE.compareAbsoluteValue(RHS.U.IEEE);
845 if (usesLayout<DoubleAPFloat>(getSemantics()))
846 return U.Double.compareAbsoluteValue(RHS.U.Double);
847 llvm_unreachable("Unexpected semantics");
850 public:
851 APFloat(const fltSemantics &Semantics) : U(Semantics) {}
852 APFloat(const fltSemantics &Semantics, StringRef S);
853 APFloat(const fltSemantics &Semantics, integerPart I) : U(Semantics, I) {}
854 // TODO: Remove this constructor. This isn't faster than the first one.
855 APFloat(const fltSemantics &Semantics, uninitializedTag)
856 : U(Semantics, uninitialized) {}
857 APFloat(const fltSemantics &Semantics, const APInt &I) : U(Semantics, I) {}
858 explicit APFloat(double d) : U(IEEEFloat(d), IEEEdouble()) {}
859 explicit APFloat(float f) : U(IEEEFloat(f), IEEEsingle()) {}
860 APFloat(const APFloat &RHS) = default;
861 APFloat(APFloat &&RHS) = default;
863 ~APFloat() = default;
865 bool needsCleanup() const { APFLOAT_DISPATCH_ON_SEMANTICS(needsCleanup()); }
867 /// Factory for Positive and Negative Zero.
869 /// \param Negative True iff the number should be negative.
870 static APFloat getZero(const fltSemantics &Sem, bool Negative = false) {
871 APFloat Val(Sem, uninitialized);
872 Val.makeZero(Negative);
873 return Val;
876 /// Factory for Positive and Negative Infinity.
878 /// \param Negative True iff the number should be negative.
879 static APFloat getInf(const fltSemantics &Sem, bool Negative = false) {
880 APFloat Val(Sem, uninitialized);
881 Val.makeInf(Negative);
882 return Val;
885 /// Factory for NaN values.
887 /// \param Negative - True iff the NaN generated should be negative.
888 /// \param payload - The unspecified fill bits for creating the NaN, 0 by
889 /// default. The value is truncated as necessary.
890 static APFloat getNaN(const fltSemantics &Sem, bool Negative = false,
891 uint64_t payload = 0) {
892 if (payload) {
893 APInt intPayload(64, payload);
894 return getQNaN(Sem, Negative, &intPayload);
895 } else {
896 return getQNaN(Sem, Negative, nullptr);
900 /// Factory for QNaN values.
901 static APFloat getQNaN(const fltSemantics &Sem, bool Negative = false,
902 const APInt *payload = nullptr) {
903 APFloat Val(Sem, uninitialized);
904 Val.makeNaN(false, Negative, payload);
905 return Val;
908 /// Factory for SNaN values.
909 static APFloat getSNaN(const fltSemantics &Sem, bool Negative = false,
910 const APInt *payload = nullptr) {
911 APFloat Val(Sem, uninitialized);
912 Val.makeNaN(true, Negative, payload);
913 return Val;
916 /// Returns the largest finite number in the given semantics.
918 /// \param Negative - True iff the number should be negative
919 static APFloat getLargest(const fltSemantics &Sem, bool Negative = false) {
920 APFloat Val(Sem, uninitialized);
921 Val.makeLargest(Negative);
922 return Val;
925 /// Returns the smallest (by magnitude) finite number in the given semantics.
926 /// Might be denormalized, which implies a relative loss of precision.
928 /// \param Negative - True iff the number should be negative
929 static APFloat getSmallest(const fltSemantics &Sem, bool Negative = false) {
930 APFloat Val(Sem, uninitialized);
931 Val.makeSmallest(Negative);
932 return Val;
935 /// Returns the smallest (by magnitude) normalized finite number in the given
936 /// semantics.
938 /// \param Negative - True iff the number should be negative
939 static APFloat getSmallestNormalized(const fltSemantics &Sem,
940 bool Negative = false) {
941 APFloat Val(Sem, uninitialized);
942 Val.makeSmallestNormalized(Negative);
943 return Val;
946 /// Returns a float which is bitcasted from an all one value int.
948 /// \param BitWidth - Select float type
949 /// \param isIEEE - If 128 bit number, select between PPC and IEEE
950 static APFloat getAllOnesValue(unsigned BitWidth, bool isIEEE = false);
952 /// Used to insert APFloat objects, or objects that contain APFloat objects,
953 /// into FoldingSets.
954 void Profile(FoldingSetNodeID &NID) const;
956 opStatus add(const APFloat &RHS, roundingMode RM) {
957 assert(&getSemantics() == &RHS.getSemantics() &&
958 "Should only call on two APFloats with the same semantics");
959 if (usesLayout<IEEEFloat>(getSemantics()))
960 return U.IEEE.add(RHS.U.IEEE, RM);
961 if (usesLayout<DoubleAPFloat>(getSemantics()))
962 return U.Double.add(RHS.U.Double, RM);
963 llvm_unreachable("Unexpected semantics");
965 opStatus subtract(const APFloat &RHS, roundingMode RM) {
966 assert(&getSemantics() == &RHS.getSemantics() &&
967 "Should only call on two APFloats with the same semantics");
968 if (usesLayout<IEEEFloat>(getSemantics()))
969 return U.IEEE.subtract(RHS.U.IEEE, RM);
970 if (usesLayout<DoubleAPFloat>(getSemantics()))
971 return U.Double.subtract(RHS.U.Double, RM);
972 llvm_unreachable("Unexpected semantics");
974 opStatus multiply(const APFloat &RHS, roundingMode RM) {
975 assert(&getSemantics() == &RHS.getSemantics() &&
976 "Should only call on two APFloats with the same semantics");
977 if (usesLayout<IEEEFloat>(getSemantics()))
978 return U.IEEE.multiply(RHS.U.IEEE, RM);
979 if (usesLayout<DoubleAPFloat>(getSemantics()))
980 return U.Double.multiply(RHS.U.Double, RM);
981 llvm_unreachable("Unexpected semantics");
983 opStatus divide(const APFloat &RHS, roundingMode RM) {
984 assert(&getSemantics() == &RHS.getSemantics() &&
985 "Should only call on two APFloats with the same semantics");
986 if (usesLayout<IEEEFloat>(getSemantics()))
987 return U.IEEE.divide(RHS.U.IEEE, RM);
988 if (usesLayout<DoubleAPFloat>(getSemantics()))
989 return U.Double.divide(RHS.U.Double, RM);
990 llvm_unreachable("Unexpected semantics");
992 opStatus remainder(const APFloat &RHS) {
993 assert(&getSemantics() == &RHS.getSemantics() &&
994 "Should only call on two APFloats with the same semantics");
995 if (usesLayout<IEEEFloat>(getSemantics()))
996 return U.IEEE.remainder(RHS.U.IEEE);
997 if (usesLayout<DoubleAPFloat>(getSemantics()))
998 return U.Double.remainder(RHS.U.Double);
999 llvm_unreachable("Unexpected semantics");
1001 opStatus mod(const APFloat &RHS) {
1002 assert(&getSemantics() == &RHS.getSemantics() &&
1003 "Should only call on two APFloats with the same semantics");
1004 if (usesLayout<IEEEFloat>(getSemantics()))
1005 return U.IEEE.mod(RHS.U.IEEE);
1006 if (usesLayout<DoubleAPFloat>(getSemantics()))
1007 return U.Double.mod(RHS.U.Double);
1008 llvm_unreachable("Unexpected semantics");
1010 opStatus fusedMultiplyAdd(const APFloat &Multiplicand, const APFloat &Addend,
1011 roundingMode RM) {
1012 assert(&getSemantics() == &Multiplicand.getSemantics() &&
1013 "Should only call on APFloats with the same semantics");
1014 assert(&getSemantics() == &Addend.getSemantics() &&
1015 "Should only call on APFloats with the same semantics");
1016 if (usesLayout<IEEEFloat>(getSemantics()))
1017 return U.IEEE.fusedMultiplyAdd(Multiplicand.U.IEEE, Addend.U.IEEE, RM);
1018 if (usesLayout<DoubleAPFloat>(getSemantics()))
1019 return U.Double.fusedMultiplyAdd(Multiplicand.U.Double, Addend.U.Double,
1020 RM);
1021 llvm_unreachable("Unexpected semantics");
1023 opStatus roundToIntegral(roundingMode RM) {
1024 APFLOAT_DISPATCH_ON_SEMANTICS(roundToIntegral(RM));
1027 // TODO: bool parameters are not readable and a source of bugs.
1028 // Do something.
1029 opStatus next(bool nextDown) {
1030 APFLOAT_DISPATCH_ON_SEMANTICS(next(nextDown));
1033 /// Add two APFloats, rounding ties to the nearest even.
1034 /// No error checking.
1035 APFloat operator+(const APFloat &RHS) const {
1036 APFloat Result(*this);
1037 (void)Result.add(RHS, rmNearestTiesToEven);
1038 return Result;
1041 /// Subtract two APFloats, rounding ties to the nearest even.
1042 /// No error checking.
1043 APFloat operator-(const APFloat &RHS) const {
1044 APFloat Result(*this);
1045 (void)Result.subtract(RHS, rmNearestTiesToEven);
1046 return Result;
1049 /// Multiply two APFloats, rounding ties to the nearest even.
1050 /// No error checking.
1051 APFloat operator*(const APFloat &RHS) const {
1052 APFloat Result(*this);
1053 (void)Result.multiply(RHS, rmNearestTiesToEven);
1054 return Result;
1057 /// Divide the first APFloat by the second, rounding ties to the nearest even.
1058 /// No error checking.
1059 APFloat operator/(const APFloat &RHS) const {
1060 APFloat Result(*this);
1061 (void)Result.divide(RHS, rmNearestTiesToEven);
1062 return Result;
1065 void changeSign() { APFLOAT_DISPATCH_ON_SEMANTICS(changeSign()); }
1066 void clearSign() {
1067 if (isNegative())
1068 changeSign();
1070 void copySign(const APFloat &RHS) {
1071 if (isNegative() != RHS.isNegative())
1072 changeSign();
1075 /// A static helper to produce a copy of an APFloat value with its sign
1076 /// copied from some other APFloat.
1077 static APFloat copySign(APFloat Value, const APFloat &Sign) {
1078 Value.copySign(Sign);
1079 return Value;
1082 opStatus convert(const fltSemantics &ToSemantics, roundingMode RM,
1083 bool *losesInfo);
1084 opStatus convertToInteger(MutableArrayRef<integerPart> Input,
1085 unsigned int Width, bool IsSigned, roundingMode RM,
1086 bool *IsExact) const {
1087 APFLOAT_DISPATCH_ON_SEMANTICS(
1088 convertToInteger(Input, Width, IsSigned, RM, IsExact));
1090 opStatus convertToInteger(APSInt &Result, roundingMode RM,
1091 bool *IsExact) const;
1092 opStatus convertFromAPInt(const APInt &Input, bool IsSigned,
1093 roundingMode RM) {
1094 APFLOAT_DISPATCH_ON_SEMANTICS(convertFromAPInt(Input, IsSigned, RM));
1096 opStatus convertFromSignExtendedInteger(const integerPart *Input,
1097 unsigned int InputSize, bool IsSigned,
1098 roundingMode RM) {
1099 APFLOAT_DISPATCH_ON_SEMANTICS(
1100 convertFromSignExtendedInteger(Input, InputSize, IsSigned, RM));
1102 opStatus convertFromZeroExtendedInteger(const integerPart *Input,
1103 unsigned int InputSize, bool IsSigned,
1104 roundingMode RM) {
1105 APFLOAT_DISPATCH_ON_SEMANTICS(
1106 convertFromZeroExtendedInteger(Input, InputSize, IsSigned, RM));
1108 opStatus convertFromString(StringRef, roundingMode);
1109 APInt bitcastToAPInt() const {
1110 APFLOAT_DISPATCH_ON_SEMANTICS(bitcastToAPInt());
1112 double convertToDouble() const { return getIEEE().convertToDouble(); }
1113 float convertToFloat() const { return getIEEE().convertToFloat(); }
1115 bool operator==(const APFloat &) const = delete;
1117 cmpResult compare(const APFloat &RHS) const {
1118 assert(&getSemantics() == &RHS.getSemantics() &&
1119 "Should only compare APFloats with the same semantics");
1120 if (usesLayout<IEEEFloat>(getSemantics()))
1121 return U.IEEE.compare(RHS.U.IEEE);
1122 if (usesLayout<DoubleAPFloat>(getSemantics()))
1123 return U.Double.compare(RHS.U.Double);
1124 llvm_unreachable("Unexpected semantics");
1127 bool bitwiseIsEqual(const APFloat &RHS) const {
1128 if (&getSemantics() != &RHS.getSemantics())
1129 return false;
1130 if (usesLayout<IEEEFloat>(getSemantics()))
1131 return U.IEEE.bitwiseIsEqual(RHS.U.IEEE);
1132 if (usesLayout<DoubleAPFloat>(getSemantics()))
1133 return U.Double.bitwiseIsEqual(RHS.U.Double);
1134 llvm_unreachable("Unexpected semantics");
1137 /// We don't rely on operator== working on double values, as
1138 /// it returns true for things that are clearly not equal, like -0.0 and 0.0.
1139 /// As such, this method can be used to do an exact bit-for-bit comparison of
1140 /// two floating point values.
1142 /// We leave the version with the double argument here because it's just so
1143 /// convenient to write "2.0" and the like. Without this function we'd
1144 /// have to duplicate its logic everywhere it's called.
1145 bool isExactlyValue(double V) const {
1146 bool ignored;
1147 APFloat Tmp(V);
1148 Tmp.convert(getSemantics(), APFloat::rmNearestTiesToEven, &ignored);
1149 return bitwiseIsEqual(Tmp);
1152 unsigned int convertToHexString(char *DST, unsigned int HexDigits,
1153 bool UpperCase, roundingMode RM) const {
1154 APFLOAT_DISPATCH_ON_SEMANTICS(
1155 convertToHexString(DST, HexDigits, UpperCase, RM));
1158 bool isZero() const { return getCategory() == fcZero; }
1159 bool isInfinity() const { return getCategory() == fcInfinity; }
1160 bool isNaN() const { return getCategory() == fcNaN; }
1162 bool isNegative() const { return getIEEE().isNegative(); }
1163 bool isDenormal() const { APFLOAT_DISPATCH_ON_SEMANTICS(isDenormal()); }
1164 bool isSignaling() const { return getIEEE().isSignaling(); }
1166 bool isNormal() const { return !isDenormal() && isFiniteNonZero(); }
1167 bool isFinite() const { return !isNaN() && !isInfinity(); }
1169 fltCategory getCategory() const { return getIEEE().getCategory(); }
1170 const fltSemantics &getSemantics() const { return *U.semantics; }
1171 bool isNonZero() const { return !isZero(); }
1172 bool isFiniteNonZero() const { return isFinite() && !isZero(); }
1173 bool isPosZero() const { return isZero() && !isNegative(); }
1174 bool isNegZero() const { return isZero() && isNegative(); }
1175 bool isSmallest() const { APFLOAT_DISPATCH_ON_SEMANTICS(isSmallest()); }
1176 bool isLargest() const { APFLOAT_DISPATCH_ON_SEMANTICS(isLargest()); }
1177 bool isInteger() const { APFLOAT_DISPATCH_ON_SEMANTICS(isInteger()); }
1179 APFloat &operator=(const APFloat &RHS) = default;
1180 APFloat &operator=(APFloat &&RHS) = default;
1182 void toString(SmallVectorImpl<char> &Str, unsigned FormatPrecision = 0,
1183 unsigned FormatMaxPadding = 3, bool TruncateZero = true) const {
1184 APFLOAT_DISPATCH_ON_SEMANTICS(
1185 toString(Str, FormatPrecision, FormatMaxPadding, TruncateZero));
1188 void print(raw_ostream &) const;
1189 void dump() const;
1191 bool getExactInverse(APFloat *inv) const {
1192 APFLOAT_DISPATCH_ON_SEMANTICS(getExactInverse(inv));
1195 friend hash_code hash_value(const APFloat &Arg);
1196 friend int ilogb(const APFloat &Arg) { return ilogb(Arg.getIEEE()); }
1197 friend APFloat scalbn(APFloat X, int Exp, roundingMode RM);
1198 friend APFloat frexp(const APFloat &X, int &Exp, roundingMode RM);
1199 friend IEEEFloat;
1200 friend DoubleAPFloat;
1203 /// See friend declarations above.
1205 /// These additional declarations are required in order to compile LLVM with IBM
1206 /// xlC compiler.
1207 hash_code hash_value(const APFloat &Arg);
1208 inline APFloat scalbn(APFloat X, int Exp, APFloat::roundingMode RM) {
1209 if (APFloat::usesLayout<detail::IEEEFloat>(X.getSemantics()))
1210 return APFloat(scalbn(X.U.IEEE, Exp, RM), X.getSemantics());
1211 if (APFloat::usesLayout<detail::DoubleAPFloat>(X.getSemantics()))
1212 return APFloat(scalbn(X.U.Double, Exp, RM), X.getSemantics());
1213 llvm_unreachable("Unexpected semantics");
1216 /// Equivalent of C standard library function.
1218 /// While the C standard says Exp is an unspecified value for infinity and nan,
1219 /// this returns INT_MAX for infinities, and INT_MIN for NaNs.
1220 inline APFloat frexp(const APFloat &X, int &Exp, APFloat::roundingMode RM) {
1221 if (APFloat::usesLayout<detail::IEEEFloat>(X.getSemantics()))
1222 return APFloat(frexp(X.U.IEEE, Exp, RM), X.getSemantics());
1223 if (APFloat::usesLayout<detail::DoubleAPFloat>(X.getSemantics()))
1224 return APFloat(frexp(X.U.Double, Exp, RM), X.getSemantics());
1225 llvm_unreachable("Unexpected semantics");
1227 /// Returns the absolute value of the argument.
1228 inline APFloat abs(APFloat X) {
1229 X.clearSign();
1230 return X;
1233 /// Returns the negated value of the argument.
1234 inline APFloat neg(APFloat X) {
1235 X.changeSign();
1236 return X;
1239 /// Implements IEEE minNum semantics. Returns the smaller of the 2 arguments if
1240 /// both are not NaN. If either argument is a NaN, returns the other argument.
1241 LLVM_READONLY
1242 inline APFloat minnum(const APFloat &A, const APFloat &B) {
1243 if (A.isNaN())
1244 return B;
1245 if (B.isNaN())
1246 return A;
1247 return (B.compare(A) == APFloat::cmpLessThan) ? B : A;
1250 /// Implements IEEE maxNum semantics. Returns the larger of the 2 arguments if
1251 /// both are not NaN. If either argument is a NaN, returns the other argument.
1252 LLVM_READONLY
1253 inline APFloat maxnum(const APFloat &A, const APFloat &B) {
1254 if (A.isNaN())
1255 return B;
1256 if (B.isNaN())
1257 return A;
1258 return (A.compare(B) == APFloat::cmpLessThan) ? B : A;
1261 /// Implements IEEE 754-2018 minimum semantics. Returns the smaller of 2
1262 /// arguments, propagating NaNs and treating -0 as less than +0.
1263 LLVM_READONLY
1264 inline APFloat minimum(const APFloat &A, const APFloat &B) {
1265 if (A.isNaN())
1266 return A;
1267 if (B.isNaN())
1268 return B;
1269 if (A.isZero() && B.isZero() && (A.isNegative() != B.isNegative()))
1270 return A.isNegative() ? A : B;
1271 return (B.compare(A) == APFloat::cmpLessThan) ? B : A;
1274 /// Implements IEEE 754-2018 maximum semantics. Returns the larger of 2
1275 /// arguments, propagating NaNs and treating -0 as less than +0.
1276 LLVM_READONLY
1277 inline APFloat maximum(const APFloat &A, const APFloat &B) {
1278 if (A.isNaN())
1279 return A;
1280 if (B.isNaN())
1281 return B;
1282 if (A.isZero() && B.isZero() && (A.isNegative() != B.isNegative()))
1283 return A.isNegative() ? B : A;
1284 return (A.compare(B) == APFloat::cmpLessThan) ? B : A;
1287 } // namespace llvm
1289 #undef APFLOAT_DISPATCH_ON_SEMANTICS
1290 #endif // LLVM_ADT_APFLOAT_H