| // Copyright 2017 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef V8_BOXED_FLOAT_H_ |
| #define V8_BOXED_FLOAT_H_ |
| |
| #include <cmath> |
| #include "src/base/macros.h" |
| #include "src/globals.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| // TODO(ahaas): Make these classes with the one in double.h |
| |
| // Safety wrapper for a 32-bit floating-point value to make sure we don't lose |
| // the exact bit pattern during deoptimization when passing this value. |
| class Float32 { |
| public: |
| Float32() = default; |
| |
| // This constructor does not guarantee that bit pattern of the input value |
| // is preserved if the input is a NaN. |
| explicit Float32(float value) : bit_pattern_(bit_cast<uint32_t>(value)) { |
| // Check that the provided value is not a NaN, because the bit pattern of a |
| // NaN may be changed by a bit_cast, e.g. for signalling NaNs on ia32. |
| DCHECK(!std::isnan(value)); |
| } |
| |
| uint32_t get_bits() const { return bit_pattern_; } |
| |
| float get_scalar() const { return bit_cast<float>(bit_pattern_); } |
| |
| bool is_nan() const { |
| // Even though {get_scalar()} might flip the quiet NaN bit, it's ok here, |
| // because this does not change the is_nan property. |
| return std::isnan(get_scalar()); |
| } |
| |
| // Return a pointer to the field storing the bit pattern. Used in code |
| // generation tests to store generated values there directly. |
| uint32_t* get_bits_address() { return &bit_pattern_; } |
| |
| static constexpr Float32 FromBits(uint32_t bits) { return Float32(bits); } |
| |
| private: |
| uint32_t bit_pattern_ = 0; |
| |
| explicit constexpr Float32(uint32_t bit_pattern) |
| : bit_pattern_(bit_pattern) {} |
| }; |
| |
| static_assert(IS_TRIVIALLY_COPYABLE(Float32), |
| "Float32 should be trivially copyable"); |
| |
| // Safety wrapper for a 64-bit floating-point value to make sure we don't lose |
| // the exact bit pattern during deoptimization when passing this value. |
| // TODO(ahaas): Unify this class with Double in double.h |
| class Float64 { |
| public: |
| Float64() = default; |
| |
| // This constructor does not guarantee that bit pattern of the input value |
| // is preserved if the input is a NaN. |
| explicit Float64(double value) : bit_pattern_(bit_cast<uint64_t>(value)) { |
| // Check that the provided value is not a NaN, because the bit pattern of a |
| // NaN may be changed by a bit_cast, e.g. for signalling NaNs on ia32. |
| DCHECK(!std::isnan(value)); |
| } |
| |
| uint64_t get_bits() const { return bit_pattern_; } |
| double get_scalar() const { return bit_cast<double>(bit_pattern_); } |
| bool is_hole_nan() const { return bit_pattern_ == kHoleNanInt64; } |
| bool is_nan() const { |
| // Even though {get_scalar()} might flip the quiet NaN bit, it's ok here, |
| // because this does not change the is_nan property. |
| return std::isnan(get_scalar()); |
| } |
| |
| // Return a pointer to the field storing the bit pattern. Used in code |
| // generation tests to store generated values there directly. |
| uint64_t* get_bits_address() { return &bit_pattern_; } |
| |
| static constexpr Float64 FromBits(uint64_t bits) { return Float64(bits); } |
| |
| private: |
| uint64_t bit_pattern_ = 0; |
| |
| explicit constexpr Float64(uint64_t bit_pattern) |
| : bit_pattern_(bit_pattern) {} |
| }; |
| |
| static_assert(IS_TRIVIALLY_COPYABLE(Float64), |
| "Float64 should be trivially copyable"); |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_BOXED_FLOAT_H_ |