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llvm-mirror/include/llvm/ADT/APFloat.h
Serguei Katkov 6a3381464c [AsmWriter/APFloat] FP constant printing: Avoid usage of locale dependent snprinf 
This should fix the bug https://bugs.llvm.org/show_bug.cgi?id=12906

To print the FP constant AsmWriter does the following:

  1) convert FP value to String (actually using snprintf function which is locale dependent).
  2) Convert String back to FP Value
  3) Compare original and got FP values. If they are not equal just dump as hex.

The problem happens on the 2nd step when APFloat does not expect group delimiter or
fraction delimiter other than period symbol and so on, which can be produced on the
first step if LLVM library is used in an environment with corresponding locale set.

To fix this issue the locale independent APFloat:toString function is used.
However it prints FP values slightly differently than snprintf does. Specifically
it suppress trailing zeros in significant, use capital E and so on.
It results in 117 test failures during make check.
To avoid this I've also updated APFloat.toString a bit to pass make check at least.

Reviewers: sberg, bogner, majnemer, sanjoy, timshen, rnk

Reviewed By: timshen, rnk

Subscribers: rnk, llvm-commits

Differential Revision: https://reviews.llvm.org/D32276

llvm-svn: 300943
2017-04-21 02:52:17 +00:00

1235 lines
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//===- llvm/ADT/APFloat.h - Arbitrary Precision Floating Point ---*- C++ -*-==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief
/// This file declares a class to represent arbitrary precision floating point
/// values and provide a variety of arithmetic operations on them.
///
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_APFLOAT_H
#define LLVM_ADT_APFLOAT_H
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/Support/ErrorHandling.h"
#include <memory>
#define APFLOAT_DISPATCH_ON_SEMANTICS(METHOD_CALL) \
do { \
if (usesLayout<IEEEFloat>(getSemantics())) \
return U.IEEE.METHOD_CALL; \
if (usesLayout<DoubleAPFloat>(getSemantics())) \
return U.Double.METHOD_CALL; \
llvm_unreachable("Unexpected semantics"); \
} while (false)
namespace llvm {
struct fltSemantics;
class APSInt;
class StringRef;
class APFloat;
class raw_ostream;
template <typename T> class SmallVectorImpl;
/// Enum that represents what fraction of the LSB truncated bits of an fp number
/// represent.
///
/// This essentially combines the roles of guard and sticky bits.
enum lostFraction { // Example of truncated bits:
lfExactlyZero, // 000000
lfLessThanHalf, // 0xxxxx x's not all zero
lfExactlyHalf, // 100000
lfMoreThanHalf // 1xxxxx x's not all zero
};
/// 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.
///
// This is the common type definitions shared by APFloat and its internal
// implementation classes. This struct should not define any non-static data
// members.
struct APFloatBase {
// TODO remove this and use APInt typedef directly.
typedef APInt::WordType integerPart;
/// A signed type to represent a floating point numbers unbiased exponent.
typedef signed short ExponentType;
/// \name Floating Point Semantics.
/// @{
static const fltSemantics &IEEEhalf() LLVM_READNONE;
static const fltSemantics &IEEEsingle() LLVM_READNONE;
static const fltSemantics &IEEEdouble() LLVM_READNONE;
static const fltSemantics &IEEEquad() LLVM_READNONE;
static const fltSemantics &PPCDoubleDouble() LLVM_READNONE;
static const fltSemantics &x87DoubleExtended() LLVM_READNONE;
/// A Pseudo fltsemantic used to construct APFloats that cannot conflict with
/// anything real.
static const fltSemantics &Bogus() LLVM_READNONE;
/// @}
/// IEEE-754R 5.11: Floating Point Comparison Relations.
enum cmpResult {
cmpLessThan,
cmpEqual,
cmpGreaterThan,
cmpUnordered
};
/// IEEE-754R 4.3: Rounding-direction attributes.
enum roundingMode {
rmNearestTiesToEven,
rmTowardPositive,
rmTowardNegative,
rmTowardZero,
rmNearestTiesToAway
};
/// IEEE-754R 7: Default exception handling.
///
/// opUnderflow or opOverflow are always returned or-ed with opInexact.
enum opStatus {
opOK = 0x00,
opInvalidOp = 0x01,
opDivByZero = 0x02,
opOverflow = 0x04,
opUnderflow = 0x08,
opInexact = 0x10
};
/// Category of internally-represented number.
enum fltCategory {
fcInfinity,
fcNaN,
fcNormal,
fcZero
};
/// Convenience enum used to construct an uninitialized APFloat.
enum uninitializedTag {
uninitialized
};
/// Enumeration of \c ilogb error results.
enum IlogbErrorKinds {
IEK_Zero = INT_MIN + 1,
IEK_NaN = INT_MIN,
IEK_Inf = INT_MAX
};
static unsigned int semanticsPrecision(const fltSemantics &);
static ExponentType semanticsMinExponent(const fltSemantics &);
static ExponentType semanticsMaxExponent(const fltSemantics &);
static unsigned int semanticsSizeInBits(const fltSemantics &);
/// Returns the size of the floating point number (in bits) in the given
/// semantics.
static unsigned getSizeInBits(const fltSemantics &Sem);
};
namespace detail {
class IEEEFloat final : public APFloatBase {
public:
/// \name Constructors
/// @{
IEEEFloat(const fltSemantics &); // Default construct to 0.0
IEEEFloat(const fltSemantics &, integerPart);
IEEEFloat(const fltSemantics &, uninitializedTag);
IEEEFloat(const fltSemantics &, const APInt &);
explicit IEEEFloat(double d);
explicit IEEEFloat(float f);
IEEEFloat(const IEEEFloat &);
IEEEFloat(IEEEFloat &&);
~IEEEFloat();
/// @}
/// Returns whether this instance allocated memory.
bool needsCleanup() const { return partCount() > 1; }
/// \name Convenience "constructors"
/// @{
/// @}
/// \name Arithmetic
/// @{
opStatus add(const IEEEFloat &, roundingMode);
opStatus subtract(const IEEEFloat &, roundingMode);
opStatus multiply(const IEEEFloat &, roundingMode);
opStatus divide(const IEEEFloat &, roundingMode);
/// IEEE remainder.
opStatus remainder(const IEEEFloat &);
/// C fmod, or llvm frem.
opStatus mod(const IEEEFloat &);
opStatus fusedMultiplyAdd(const IEEEFloat &, const IEEEFloat &, roundingMode);
opStatus roundToIntegral(roundingMode);
/// IEEE-754R 5.3.1: nextUp/nextDown.
opStatus next(bool nextDown);
/// @}
/// \name Sign operations.
/// @{
void changeSign();
/// @}
/// \name Conversions
/// @{
opStatus convert(const fltSemantics &, roundingMode, bool *);
opStatus convertToInteger(MutableArrayRef<integerPart>, unsigned int, bool,
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;
/// @}
/// 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.
bool operator==(const IEEEFloat &) const = delete;
/// IEEE comparison with another floating point number (NaNs compare
/// unordered, 0==-0).
cmpResult compare(const IEEEFloat &) const;
/// Bitwise comparison for equality (QNaNs compare equal, 0!=-0).
bool bitwiseIsEqual(const IEEEFloat &) 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.
unsigned int convertToHexString(char *dst, unsigned int hexDigits,
bool upperCase, roundingMode) const;
/// \name IEEE-754R 5.7.2 General operations.
/// @{
/// IEEE-754R isSignMinus: Returns true if and only if the current value is
/// negative.
///
/// This applies to zeros and NaNs as well.
bool isNegative() const { return sign; }
/// 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.
bool isNormal() const { return !isDenormal() && isFiniteNonZero(); }
/// Returns true if and only if the current value is zero, subnormal, or
/// normal.
///
/// This means that the value is not infinite or NaN.
bool isFinite() const { return !isNaN() && !isInfinity(); }
/// Returns true if and only if the float is plus or minus zero.
bool isZero() const { return category == fcZero; }
/// IEEE-754R isSubnormal(): Returns true if and only if the float is a
/// denormal.
bool isDenormal() const;
/// IEEE-754R isInfinite(): Returns true if and only if the float is infinity.
bool isInfinity() const { return category == fcInfinity; }
/// Returns true if and only if the float is a quiet or signaling NaN.
bool isNaN() const { return category == fcNaN; }
/// Returns true if and only if the float is a signaling NaN.
bool isSignaling() const;
/// @}
/// \name Simple Queries
/// @{
fltCategory getCategory() const { return category; }
const fltSemantics &getSemantics() const { return *semantics; }
bool isNonZero() const { return category != fcZero; }
bool isFiniteNonZero() const { return isFinite() && !isZero(); }
bool isPosZero() const { return isZero() && !isNegative(); }
bool isNegZero() const { return isZero() && isNegative(); }
/// Returns true if and only if the number has the smallest possible non-zero
/// magnitude in the current semantics.
bool isSmallest() const;
/// Returns true if and only if the number has the largest possible finite
/// magnitude in the current semantics.
bool isLargest() const;
/// Returns true if and only if the number is an exact integer.
bool isInteger() const;
/// @}
IEEEFloat &operator=(const IEEEFloat &);
IEEEFloat &operator=(IEEEFloat &&);
/// 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.
friend hash_code hash_value(const IEEEFloat &Arg);
/// Converts this value into a decimal string.
///
/// \param FormatPrecision The 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.
/// \param FormatMaxPadding The maximum number of zeros to
/// consider inserting before falling back to scientific
/// notation. 0 means to always use scientific notation.
///
/// \param TruncateZero Indicate whether to remove the trailing zero in
/// fraction part or not. Also setting this parameter to false forcing
/// producing of output more similar to default printf behavior.
/// Specifically the lower e is used as exponent delimiter and exponent
/// always contains no less than two digits.
///
/// 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
void toString(SmallVectorImpl<char> &Str, unsigned FormatPrecision = 0,
unsigned FormatMaxPadding = 3, bool TruncateZero = true) const;
/// If this value has an exact multiplicative inverse, store it in inv and
/// return true.
bool getExactInverse(APFloat *inv) const;
/// 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 -> \c IEK_NaN
/// 0 -> \c IEK_Zero
/// Inf -> \c IEK_Inf
///
friend int ilogb(const IEEEFloat &Arg);
/// Returns: X * 2^Exp for integral exponents.
friend IEEEFloat scalbn(IEEEFloat X, int Exp, roundingMode);
friend IEEEFloat frexp(const IEEEFloat &X, int &Exp, roundingMode);
/// \name Special value setters.
/// @{
void makeLargest(bool Neg = false);
void makeSmallest(bool Neg = false);
void makeNaN(bool SNaN = false, bool Neg = false,
const APInt *fill = nullptr);
void makeInf(bool Neg = false);
void makeZero(bool Neg = false);
void makeQuiet();
/// Returns the smallest (by magnitude) normalized finite number in the given
/// semantics.
///
/// \param Negative - True iff the number should be negative
void makeSmallestNormalized(bool Negative = false);
/// @}
cmpResult compareAbsoluteValue(const IEEEFloat &) const;
private:
/// \name Simple Queries
/// @{
integerPart *significandParts();
const integerPart *significandParts() const;
unsigned int partCount() const;
/// @}
/// \name Significand operations.
/// @{
integerPart addSignificand(const IEEEFloat &);
integerPart subtractSignificand(const IEEEFloat &, integerPart);
lostFraction addOrSubtractSignificand(const IEEEFloat &, bool subtract);
lostFraction multiplySignificand(const IEEEFloat &, const IEEEFloat *);
lostFraction divideSignificand(const IEEEFloat &);
void incrementSignificand();
void initialize(const fltSemantics *);
void shiftSignificandLeft(unsigned int);
lostFraction shiftSignificandRight(unsigned int);
unsigned int significandLSB() const;
unsigned int significandMSB() const;
void zeroSignificand();
/// Return true if the significand excluding the integral bit is all ones.
bool isSignificandAllOnes() const;
/// Return true if the significand excluding the integral bit is all zeros.
bool isSignificandAllZeros() const;
/// @}
/// \name Arithmetic on special values.
/// @{
opStatus addOrSubtractSpecials(const IEEEFloat &, bool subtract);
opStatus divideSpecials(const IEEEFloat &);
opStatus multiplySpecials(const IEEEFloat &);
opStatus modSpecials(const IEEEFloat &);
/// @}
/// \name Miscellany
/// @{
bool convertFromStringSpecials(StringRef str);
opStatus normalize(roundingMode, lostFraction);
opStatus addOrSubtract(const IEEEFloat &, roundingMode, bool subtract);
opStatus handleOverflow(roundingMode);
bool roundAwayFromZero(roundingMode, lostFraction, unsigned int) const;
opStatus convertToSignExtendedInteger(MutableArrayRef<integerPart>,
unsigned int, bool, roundingMode,
bool *) const;
opStatus convertFromUnsignedParts(const integerPart *, unsigned int,
roundingMode);
opStatus convertFromHexadecimalString(StringRef, roundingMode);
opStatus convertFromDecimalString(StringRef, roundingMode);
char *convertNormalToHexString(char *, unsigned int, bool,
roundingMode) const;
opStatus roundSignificandWithExponent(const integerPart *, unsigned int, int,
roundingMode);
/// @}
APInt convertHalfAPFloatToAPInt() const;
APInt convertFloatAPFloatToAPInt() const;
APInt convertDoubleAPFloatToAPInt() const;
APInt convertQuadrupleAPFloatToAPInt() const;
APInt convertF80LongDoubleAPFloatToAPInt() const;
APInt convertPPCDoubleDoubleAPFloatToAPInt() const;
void initFromAPInt(const fltSemantics *Sem, const APInt &api);
void initFromHalfAPInt(const APInt &api);
void initFromFloatAPInt(const APInt &api);
void initFromDoubleAPInt(const APInt &api);
void initFromQuadrupleAPInt(const APInt &api);
void initFromF80LongDoubleAPInt(const APInt &api);
void initFromPPCDoubleDoubleAPInt(const APInt &api);
void assign(const IEEEFloat &);
void copySignificand(const IEEEFloat &);
void freeSignificand();
/// Note: this must be the first data member.
/// The semantics that this value obeys.
const fltSemantics *semantics;
/// A binary fraction with an explicit integer bit.
///
/// The significand must be at least one bit wider than the target precision.
union Significand {
integerPart part;
integerPart *parts;
} significand;
/// The signed unbiased exponent of the value.
ExponentType exponent;
/// What kind of floating point number this is.
///
/// Only 2 bits are required, but VisualStudio incorrectly sign extends it.
/// Using the extra bit keeps it from failing under VisualStudio.
fltCategory category : 3;
/// Sign bit of the number.
unsigned int sign : 1;
};
hash_code hash_value(const IEEEFloat &Arg);
int ilogb(const IEEEFloat &Arg);
IEEEFloat scalbn(IEEEFloat X, int Exp, IEEEFloat::roundingMode);
IEEEFloat frexp(const IEEEFloat &Val, int &Exp, IEEEFloat::roundingMode RM);
// This mode implements more precise float in terms of two APFloats.
// The interface and layout is designed for arbitray underlying semantics,
// though currently only PPCDoubleDouble semantics are supported, whose
// corresponding underlying semantics are IEEEdouble.
class DoubleAPFloat final : public APFloatBase {
// Note: this must be the first data member.
const fltSemantics *Semantics;
std::unique_ptr<APFloat[]> Floats;
opStatus addImpl(const APFloat &a, const APFloat &aa, const APFloat &c,
const APFloat &cc, roundingMode RM);
opStatus addWithSpecial(const DoubleAPFloat &LHS, const DoubleAPFloat &RHS,
DoubleAPFloat &Out, roundingMode RM);
public:
DoubleAPFloat(const fltSemantics &S);
DoubleAPFloat(const fltSemantics &S, uninitializedTag);
DoubleAPFloat(const fltSemantics &S, integerPart);
DoubleAPFloat(const fltSemantics &S, const APInt &I);
DoubleAPFloat(const fltSemantics &S, APFloat &&First, APFloat &&Second);
DoubleAPFloat(const DoubleAPFloat &RHS);
DoubleAPFloat(DoubleAPFloat &&RHS);
DoubleAPFloat &operator=(const DoubleAPFloat &RHS);
DoubleAPFloat &operator=(DoubleAPFloat &&RHS) {
if (this != &RHS) {
this->~DoubleAPFloat();
new (this) DoubleAPFloat(std::move(RHS));
}
return *this;
}
bool needsCleanup() const { return Floats != nullptr; }
APFloat &getFirst() { return Floats[0]; }
const APFloat &getFirst() const { return Floats[0]; }
APFloat &getSecond() { return Floats[1]; }
const APFloat &getSecond() const { return Floats[1]; }
opStatus add(const DoubleAPFloat &RHS, roundingMode RM);
opStatus subtract(const DoubleAPFloat &RHS, roundingMode RM);
opStatus multiply(const DoubleAPFloat &RHS, roundingMode RM);
opStatus divide(const DoubleAPFloat &RHS, roundingMode RM);
opStatus remainder(const DoubleAPFloat &RHS);
opStatus mod(const DoubleAPFloat &RHS);
opStatus fusedMultiplyAdd(const DoubleAPFloat &Multiplicand,
const DoubleAPFloat &Addend, roundingMode RM);
opStatus roundToIntegral(roundingMode RM);
void changeSign();
cmpResult compareAbsoluteValue(const DoubleAPFloat &RHS) const;
fltCategory getCategory() const;
bool isNegative() const;
void makeInf(bool Neg);
void makeZero(bool Neg);
void makeLargest(bool Neg);
void makeSmallest(bool Neg);
void makeSmallestNormalized(bool Neg);
void makeNaN(bool SNaN, bool Neg, const APInt *fill);
cmpResult compare(const DoubleAPFloat &RHS) const;
bool bitwiseIsEqual(const DoubleAPFloat &RHS) const;
APInt bitcastToAPInt() const;
opStatus convertFromString(StringRef, roundingMode);
opStatus next(bool nextDown);
opStatus convertToInteger(MutableArrayRef<integerPart> Input,
unsigned int Width, bool IsSigned, roundingMode RM,
bool *IsExact) const;
opStatus convertFromAPInt(const APInt &Input, bool IsSigned, roundingMode RM);
opStatus convertFromSignExtendedInteger(const integerPart *Input,
unsigned int InputSize, bool IsSigned,
roundingMode RM);
opStatus convertFromZeroExtendedInteger(const integerPart *Input,
unsigned int InputSize, bool IsSigned,
roundingMode RM);
unsigned int convertToHexString(char *DST, unsigned int HexDigits,
bool UpperCase, roundingMode RM) const;
bool isDenormal() const;
bool isSmallest() const;
bool isLargest() const;
bool isInteger() const;
void toString(SmallVectorImpl<char> &Str, unsigned FormatPrecision,
unsigned FormatMaxPadding, bool TruncateZero = true) const;
bool getExactInverse(APFloat *inv) const;
friend int ilogb(const DoubleAPFloat &Arg);
friend DoubleAPFloat scalbn(DoubleAPFloat X, int Exp, roundingMode);
friend DoubleAPFloat frexp(const DoubleAPFloat &X, int &Exp, roundingMode);
friend hash_code hash_value(const DoubleAPFloat &Arg);
};
hash_code hash_value(const DoubleAPFloat &Arg);
} // End detail namespace
// This is a interface class that is currently forwarding functionalities from
// detail::IEEEFloat.
class APFloat : public APFloatBase {
typedef detail::IEEEFloat IEEEFloat;
typedef detail::DoubleAPFloat DoubleAPFloat;
static_assert(std::is_standard_layout<IEEEFloat>::value, "");
union Storage {
const fltSemantics *semantics;
IEEEFloat IEEE;
DoubleAPFloat Double;
explicit Storage(IEEEFloat F, const fltSemantics &S);
explicit Storage(DoubleAPFloat F, const fltSemantics &S)
: Double(std::move(F)) {
assert(&S == &PPCDoubleDouble());
}
template <typename... ArgTypes>
Storage(const fltSemantics &Semantics, ArgTypes &&... Args) {
if (usesLayout<IEEEFloat>(Semantics)) {
new (&IEEE) IEEEFloat(Semantics, std::forward<ArgTypes>(Args)...);
return;
}
if (usesLayout<DoubleAPFloat>(Semantics)) {
new (&Double) DoubleAPFloat(Semantics, std::forward<ArgTypes>(Args)...);
return;
}
llvm_unreachable("Unexpected semantics");
}
~Storage() {
if (usesLayout<IEEEFloat>(*semantics)) {
IEEE.~IEEEFloat();
return;
}
if (usesLayout<DoubleAPFloat>(*semantics)) {
Double.~DoubleAPFloat();
return;
}
llvm_unreachable("Unexpected semantics");
}
Storage(const Storage &RHS) {
if (usesLayout<IEEEFloat>(*RHS.semantics)) {
new (this) IEEEFloat(RHS.IEEE);
return;
}
if (usesLayout<DoubleAPFloat>(*RHS.semantics)) {
new (this) DoubleAPFloat(RHS.Double);
return;
}
llvm_unreachable("Unexpected semantics");
}
Storage(Storage &&RHS) {
if (usesLayout<IEEEFloat>(*RHS.semantics)) {
new (this) IEEEFloat(std::move(RHS.IEEE));
return;
}
if (usesLayout<DoubleAPFloat>(*RHS.semantics)) {
new (this) DoubleAPFloat(std::move(RHS.Double));
return;
}
llvm_unreachable("Unexpected semantics");
}
Storage &operator=(const Storage &RHS) {
if (usesLayout<IEEEFloat>(*semantics) &&
usesLayout<IEEEFloat>(*RHS.semantics)) {
IEEE = RHS.IEEE;
} else if (usesLayout<DoubleAPFloat>(*semantics) &&
usesLayout<DoubleAPFloat>(*RHS.semantics)) {
Double = RHS.Double;
} else if (this != &RHS) {
this->~Storage();
new (this) Storage(RHS);
}
return *this;
}
Storage &operator=(Storage &&RHS) {
if (usesLayout<IEEEFloat>(*semantics) &&
usesLayout<IEEEFloat>(*RHS.semantics)) {
IEEE = std::move(RHS.IEEE);
} else if (usesLayout<DoubleAPFloat>(*semantics) &&
usesLayout<DoubleAPFloat>(*RHS.semantics)) {
Double = std::move(RHS.Double);
} else if (this != &RHS) {
this->~Storage();
new (this) Storage(std::move(RHS));
}
return *this;
}
} U;
template <typename T> static bool usesLayout(const fltSemantics &Semantics) {
static_assert(std::is_same<T, IEEEFloat>::value ||
std::is_same<T, DoubleAPFloat>::value, "");
if (std::is_same<T, DoubleAPFloat>::value) {
return &Semantics == &PPCDoubleDouble();
}
return &Semantics != &PPCDoubleDouble();
}
IEEEFloat &getIEEE() {
if (usesLayout<IEEEFloat>(*U.semantics))
return U.IEEE;
if (usesLayout<DoubleAPFloat>(*U.semantics))
return U.Double.getFirst().U.IEEE;
llvm_unreachable("Unexpected semantics");
}
const IEEEFloat &getIEEE() const {
if (usesLayout<IEEEFloat>(*U.semantics))
return U.IEEE;
if (usesLayout<DoubleAPFloat>(*U.semantics))
return U.Double.getFirst().U.IEEE;
llvm_unreachable("Unexpected semantics");
}
void makeZero(bool Neg) { APFLOAT_DISPATCH_ON_SEMANTICS(makeZero(Neg)); }
void makeInf(bool Neg) { APFLOAT_DISPATCH_ON_SEMANTICS(makeInf(Neg)); }
void makeNaN(bool SNaN, bool Neg, const APInt *fill) {
APFLOAT_DISPATCH_ON_SEMANTICS(makeNaN(SNaN, Neg, fill));
}
void makeLargest(bool Neg) {
APFLOAT_DISPATCH_ON_SEMANTICS(makeLargest(Neg));
}
void makeSmallest(bool Neg) {
APFLOAT_DISPATCH_ON_SEMANTICS(makeSmallest(Neg));
}
void makeSmallestNormalized(bool Neg) {
APFLOAT_DISPATCH_ON_SEMANTICS(makeSmallestNormalized(Neg));
}
// FIXME: This is due to clang 3.3 (or older version) always checks for the
// default constructor in an array aggregate initialization, even if no
// elements in the array is default initialized.
APFloat() : U(IEEEdouble()) {
llvm_unreachable("This is a workaround for old clang.");
}
explicit APFloat(IEEEFloat F, const fltSemantics &S) : U(std::move(F), S) {}
explicit APFloat(DoubleAPFloat F, const fltSemantics &S)
: U(std::move(F), S) {}
cmpResult compareAbsoluteValue(const APFloat &RHS) const {
assert(&getSemantics() == &RHS.getSemantics() &&
"Should only compare APFloats with the same semantics");
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.compareAbsoluteValue(RHS.U.IEEE);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.compareAbsoluteValue(RHS.U.Double);
llvm_unreachable("Unexpected semantics");
}
public:
APFloat(const fltSemantics &Semantics) : U(Semantics) {}
APFloat(const fltSemantics &Semantics, StringRef S);
APFloat(const fltSemantics &Semantics, integerPart I) : U(Semantics, I) {}
// TODO: Remove this constructor. This isn't faster than the first one.
APFloat(const fltSemantics &Semantics, uninitializedTag)
: U(Semantics, uninitialized) {}
APFloat(const fltSemantics &Semantics, const APInt &I) : U(Semantics, I) {}
explicit APFloat(double d) : U(IEEEFloat(d), IEEEdouble()) {}
explicit APFloat(float f) : U(IEEEFloat(f), IEEEsingle()) {}
APFloat(const APFloat &RHS) = default;
APFloat(APFloat &&RHS) = default;
~APFloat() = default;
bool needsCleanup() const { APFLOAT_DISPATCH_ON_SEMANTICS(needsCleanup()); }
/// Factory for Positive and Negative Zero.
///
/// \param Negative True iff the number should be negative.
static APFloat getZero(const fltSemantics &Sem, bool Negative = false) {
APFloat Val(Sem, uninitialized);
Val.makeZero(Negative);
return Val;
}
/// Factory for Positive and Negative Infinity.
///
/// \param Negative True iff the number should be negative.
static APFloat getInf(const fltSemantics &Sem, bool Negative = false) {
APFloat Val(Sem, uninitialized);
Val.makeInf(Negative);
return Val;
}
/// Factory for NaN values.
///
/// \param Negative - True iff the NaN generated should be negative.
/// \param type - The unspecified fill bits for creating the NaN, 0 by
/// default. The value is truncated as necessary.
static APFloat getNaN(const fltSemantics &Sem, bool Negative = false,
unsigned type = 0) {
if (type) {
APInt fill(64, type);
return getQNaN(Sem, Negative, &fill);
} else {
return getQNaN(Sem, Negative, nullptr);
}
}
/// Factory for QNaN values.
static APFloat getQNaN(const fltSemantics &Sem, bool Negative = false,
const APInt *payload = nullptr) {
APFloat Val(Sem, uninitialized);
Val.makeNaN(false, Negative, payload);
return Val;
}
/// Factory for SNaN values.
static APFloat getSNaN(const fltSemantics &Sem, bool Negative = false,
const APInt *payload = nullptr) {
APFloat Val(Sem, uninitialized);
Val.makeNaN(true, Negative, payload);
return Val;
}
/// Returns the largest finite number in the given semantics.
///
/// \param Negative - True iff the number should be negative
static APFloat getLargest(const fltSemantics &Sem, bool Negative = false) {
APFloat Val(Sem, uninitialized);
Val.makeLargest(Negative);
return Val;
}
/// Returns the smallest (by magnitude) finite number in the given semantics.
/// Might be denormalized, which implies a relative loss of precision.
///
/// \param Negative - True iff the number should be negative
static APFloat getSmallest(const fltSemantics &Sem, bool Negative = false) {
APFloat Val(Sem, uninitialized);
Val.makeSmallest(Negative);
return Val;
}
/// Returns the smallest (by magnitude) normalized finite number in the given
/// semantics.
///
/// \param Negative - True iff the number should be negative
static APFloat getSmallestNormalized(const fltSemantics &Sem,
bool Negative = false) {
APFloat Val(Sem, uninitialized);
Val.makeSmallestNormalized(Negative);
return Val;
}
/// Returns a float which is bitcasted from an all one value int.
///
/// \param BitWidth - Select float type
/// \param isIEEE - If 128 bit number, select between PPC and IEEE
static APFloat getAllOnesValue(unsigned BitWidth, bool isIEEE = false);
/// Used to insert APFloat objects, or objects that contain APFloat objects,
/// into FoldingSets.
void Profile(FoldingSetNodeID &NID) const;
opStatus add(const APFloat &RHS, roundingMode RM) {
assert(&getSemantics() == &RHS.getSemantics() &&
"Should only call on two APFloats with the same semantics");
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.add(RHS.U.IEEE, RM);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.add(RHS.U.Double, RM);
llvm_unreachable("Unexpected semantics");
}
opStatus subtract(const APFloat &RHS, roundingMode RM) {
assert(&getSemantics() == &RHS.getSemantics() &&
"Should only call on two APFloats with the same semantics");
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.subtract(RHS.U.IEEE, RM);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.subtract(RHS.U.Double, RM);
llvm_unreachable("Unexpected semantics");
}
opStatus multiply(const APFloat &RHS, roundingMode RM) {
assert(&getSemantics() == &RHS.getSemantics() &&
"Should only call on two APFloats with the same semantics");
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.multiply(RHS.U.IEEE, RM);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.multiply(RHS.U.Double, RM);
llvm_unreachable("Unexpected semantics");
}
opStatus divide(const APFloat &RHS, roundingMode RM) {
assert(&getSemantics() == &RHS.getSemantics() &&
"Should only call on two APFloats with the same semantics");
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.divide(RHS.U.IEEE, RM);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.divide(RHS.U.Double, RM);
llvm_unreachable("Unexpected semantics");
}
opStatus remainder(const APFloat &RHS) {
assert(&getSemantics() == &RHS.getSemantics() &&
"Should only call on two APFloats with the same semantics");
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.remainder(RHS.U.IEEE);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.remainder(RHS.U.Double);
llvm_unreachable("Unexpected semantics");
}
opStatus mod(const APFloat &RHS) {
assert(&getSemantics() == &RHS.getSemantics() &&
"Should only call on two APFloats with the same semantics");
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.mod(RHS.U.IEEE);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.mod(RHS.U.Double);
llvm_unreachable("Unexpected semantics");
}
opStatus fusedMultiplyAdd(const APFloat &Multiplicand, const APFloat &Addend,
roundingMode RM) {
assert(&getSemantics() == &Multiplicand.getSemantics() &&
"Should only call on APFloats with the same semantics");
assert(&getSemantics() == &Addend.getSemantics() &&
"Should only call on APFloats with the same semantics");
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.fusedMultiplyAdd(Multiplicand.U.IEEE, Addend.U.IEEE, RM);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.fusedMultiplyAdd(Multiplicand.U.Double, Addend.U.Double,
RM);
llvm_unreachable("Unexpected semantics");
}
opStatus roundToIntegral(roundingMode RM) {
APFLOAT_DISPATCH_ON_SEMANTICS(roundToIntegral(RM));
}
// TODO: bool parameters are not readable and a source of bugs.
// Do something.
opStatus next(bool nextDown) {
APFLOAT_DISPATCH_ON_SEMANTICS(next(nextDown));
}
/// Add two APFloats, rounding ties to the nearest even.
/// No error checking.
APFloat operator+(const APFloat &RHS) const {
APFloat Result(*this);
(void)Result.add(RHS, rmNearestTiesToEven);
return Result;
}
/// Subtract two APFloats, rounding ties to the nearest even.
/// No error checking.
APFloat operator-(const APFloat &RHS) const {
APFloat Result(*this);
(void)Result.subtract(RHS, rmNearestTiesToEven);
return Result;
}
/// Multiply two APFloats, rounding ties to the nearest even.
/// No error checking.
APFloat operator*(const APFloat &RHS) const {
APFloat Result(*this);
(void)Result.multiply(RHS, rmNearestTiesToEven);
return Result;
}
/// Divide the first APFloat by the second, rounding ties to the nearest even.
/// No error checking.
APFloat operator/(const APFloat &RHS) const {
APFloat Result(*this);
(void)Result.divide(RHS, rmNearestTiesToEven);
return Result;
}
void changeSign() { APFLOAT_DISPATCH_ON_SEMANTICS(changeSign()); }
void clearSign() {
if (isNegative())
changeSign();
}
void copySign(const APFloat &RHS) {
if (isNegative() != RHS.isNegative())
changeSign();
}
/// A static helper to produce a copy of an APFloat value with its sign
/// copied from some other APFloat.
static APFloat copySign(APFloat Value, const APFloat &Sign) {
Value.copySign(Sign);
return Value;
}
opStatus convert(const fltSemantics &ToSemantics, roundingMode RM,
bool *losesInfo);
opStatus convertToInteger(MutableArrayRef<integerPart> Input,
unsigned int Width, bool IsSigned, roundingMode RM,
bool *IsExact) const {
APFLOAT_DISPATCH_ON_SEMANTICS(
convertToInteger(Input, Width, IsSigned, RM, IsExact));
}
opStatus convertToInteger(APSInt &Result, roundingMode RM,
bool *IsExact) const;
opStatus convertFromAPInt(const APInt &Input, bool IsSigned,
roundingMode RM) {
APFLOAT_DISPATCH_ON_SEMANTICS(convertFromAPInt(Input, IsSigned, RM));
}
opStatus convertFromSignExtendedInteger(const integerPart *Input,
unsigned int InputSize, bool IsSigned,
roundingMode RM) {
APFLOAT_DISPATCH_ON_SEMANTICS(
convertFromSignExtendedInteger(Input, InputSize, IsSigned, RM));
}
opStatus convertFromZeroExtendedInteger(const integerPart *Input,
unsigned int InputSize, bool IsSigned,
roundingMode RM) {
APFLOAT_DISPATCH_ON_SEMANTICS(
convertFromZeroExtendedInteger(Input, InputSize, IsSigned, RM));
}
opStatus convertFromString(StringRef, roundingMode);
APInt bitcastToAPInt() const {
APFLOAT_DISPATCH_ON_SEMANTICS(bitcastToAPInt());
}
double convertToDouble() const { return getIEEE().convertToDouble(); }
float convertToFloat() const { return getIEEE().convertToFloat(); }
bool operator==(const APFloat &) const = delete;
cmpResult compare(const APFloat &RHS) const {
assert(&getSemantics() == &RHS.getSemantics() &&
"Should only compare APFloats with the same semantics");
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.compare(RHS.U.IEEE);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.compare(RHS.U.Double);
llvm_unreachable("Unexpected semantics");
}
bool bitwiseIsEqual(const APFloat &RHS) const {
if (&getSemantics() != &RHS.getSemantics())
return false;
if (usesLayout<IEEEFloat>(getSemantics()))
return U.IEEE.bitwiseIsEqual(RHS.U.IEEE);
if (usesLayout<DoubleAPFloat>(getSemantics()))
return U.Double.bitwiseIsEqual(RHS.U.Double);
llvm_unreachable("Unexpected semantics");
}
unsigned int convertToHexString(char *DST, unsigned int HexDigits,
bool UpperCase, roundingMode RM) const {
APFLOAT_DISPATCH_ON_SEMANTICS(
convertToHexString(DST, HexDigits, UpperCase, RM));
}
bool isZero() const { return getCategory() == fcZero; }
bool isInfinity() const { return getCategory() == fcInfinity; }
bool isNaN() const { return getCategory() == fcNaN; }
bool isNegative() const { return getIEEE().isNegative(); }
bool isDenormal() const { APFLOAT_DISPATCH_ON_SEMANTICS(isDenormal()); }
bool isSignaling() const { return getIEEE().isSignaling(); }
bool isNormal() const { return !isDenormal() && isFiniteNonZero(); }
bool isFinite() const { return !isNaN() && !isInfinity(); }
fltCategory getCategory() const { return getIEEE().getCategory(); }
const fltSemantics &getSemantics() const { return *U.semantics; }
bool isNonZero() const { return !isZero(); }
bool isFiniteNonZero() const { return isFinite() && !isZero(); }
bool isPosZero() const { return isZero() && !isNegative(); }
bool isNegZero() const { return isZero() && isNegative(); }
bool isSmallest() const { APFLOAT_DISPATCH_ON_SEMANTICS(isSmallest()); }
bool isLargest() const { APFLOAT_DISPATCH_ON_SEMANTICS(isLargest()); }
bool isInteger() const { APFLOAT_DISPATCH_ON_SEMANTICS(isInteger()); }
APFloat &operator=(const APFloat &RHS) = default;
APFloat &operator=(APFloat &&RHS) = default;
void toString(SmallVectorImpl<char> &Str, unsigned FormatPrecision = 0,
unsigned FormatMaxPadding = 3, bool TruncateZero = true) const {
APFLOAT_DISPATCH_ON_SEMANTICS(
toString(Str, FormatPrecision, FormatMaxPadding, TruncateZero));
}
void print(raw_ostream &) const;
void dump() const;
bool getExactInverse(APFloat *inv) const {
APFLOAT_DISPATCH_ON_SEMANTICS(getExactInverse(inv));
}
friend hash_code hash_value(const APFloat &Arg);
friend int ilogb(const APFloat &Arg) { return ilogb(Arg.getIEEE()); }
friend APFloat scalbn(APFloat X, int Exp, roundingMode RM);
friend APFloat frexp(const APFloat &X, int &Exp, roundingMode RM);
friend IEEEFloat;
friend DoubleAPFloat;
};
/// See friend declarations above.
///
/// These additional declarations are required in order to compile LLVM with IBM
/// xlC compiler.
hash_code hash_value(const APFloat &Arg);
inline APFloat scalbn(APFloat X, int Exp, APFloat::roundingMode RM) {
if (APFloat::usesLayout<detail::IEEEFloat>(X.getSemantics()))
return APFloat(scalbn(X.U.IEEE, Exp, RM), X.getSemantics());
if (APFloat::usesLayout<detail::DoubleAPFloat>(X.getSemantics()))
return APFloat(scalbn(X.U.Double, Exp, RM), X.getSemantics());
llvm_unreachable("Unexpected semantics");
}
/// Equivalent of C standard library function.
///
/// While the C standard says Exp is an unspecified value for infinity and nan,
/// this returns INT_MAX for infinities, and INT_MIN for NaNs.
inline APFloat frexp(const APFloat &X, int &Exp, APFloat::roundingMode RM) {
if (APFloat::usesLayout<detail::IEEEFloat>(X.getSemantics()))
return APFloat(frexp(X.U.IEEE, Exp, RM), X.getSemantics());
if (APFloat::usesLayout<detail::DoubleAPFloat>(X.getSemantics()))
return APFloat(frexp(X.U.Double, Exp, RM), X.getSemantics());
llvm_unreachable("Unexpected semantics");
}
/// Returns the absolute value of the argument.
inline APFloat abs(APFloat X) {
X.clearSign();
return X;
}
/// \brief Returns the negated value of the argument.
inline APFloat neg(APFloat X) {
X.changeSign();
return X;
}
/// Implements IEEE minNum semantics. Returns the smaller of the 2 arguments if
/// both are not NaN. If either argument is a NaN, returns the other argument.
LLVM_READONLY
inline APFloat minnum(const APFloat &A, const APFloat &B) {
if (A.isNaN())
return B;
if (B.isNaN())
return A;
return (B.compare(A) == APFloat::cmpLessThan) ? B : A;
}
/// Implements IEEE maxNum semantics. Returns the larger of the 2 arguments if
/// both are not NaN. If either argument is a NaN, returns the other argument.
LLVM_READONLY
inline APFloat maxnum(const APFloat &A, const APFloat &B) {
if (A.isNaN())
return B;
if (B.isNaN())
return A;
return (A.compare(B) == APFloat::cmpLessThan) ? B : A;
}
} // namespace llvm
#undef APFLOAT_DISPATCH_ON_SEMANTICS
#endif // LLVM_ADT_APFLOAT_H
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