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Diffstat (limited to 'intl/icu/source/i18n/double-conversion-utils.h')
| -rw-r--r-- | intl/icu/source/i18n/double-conversion-utils.h | 389 |
1 files changed, 389 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/double-conversion-utils.h b/intl/icu/source/i18n/double-conversion-utils.h new file mode 100644 index 0000000000..8c6a0e16e0 --- /dev/null +++ b/intl/icu/source/i18n/double-conversion-utils.h @@ -0,0 +1,389 @@ +// © 2018 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +// +// From the double-conversion library. Original license: +// +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +// ICU PATCH: ifdef around UCONFIG_NO_FORMATTING +#include "unicode/utypes.h" +#if !UCONFIG_NO_FORMATTING + +#ifndef DOUBLE_CONVERSION_UTILS_H_ +#define DOUBLE_CONVERSION_UTILS_H_ + +#include <cstdlib> +#include <cstring> + +// ICU PATCH: Use U_ASSERT instead of <assert.h> +#include "uassert.h" +#ifndef DOUBLE_CONVERSION_ASSERT +#define DOUBLE_CONVERSION_ASSERT(condition) \ + U_ASSERT(condition); +#endif +#ifndef DOUBLE_CONVERSION_UNIMPLEMENTED +#define DOUBLE_CONVERSION_UNIMPLEMENTED() (abort()) +#endif +#ifndef DOUBLE_CONVERSION_NO_RETURN +#ifdef _MSC_VER +#define DOUBLE_CONVERSION_NO_RETURN __declspec(noreturn) +#else +#define DOUBLE_CONVERSION_NO_RETURN __attribute__((noreturn)) +#endif +#endif +#ifndef DOUBLE_CONVERSION_UNREACHABLE +#ifdef _MSC_VER +void DOUBLE_CONVERSION_NO_RETURN abort_noreturn(); +inline void abort_noreturn() { abort(); } +#define DOUBLE_CONVERSION_UNREACHABLE() (abort_noreturn()) +#else +#define DOUBLE_CONVERSION_UNREACHABLE() (abort()) +#endif +#endif + +// Not all compilers support __has_attribute and combining a check for both +// ifdef and __has_attribute on the same preprocessor line isn't portable. +#ifdef __has_attribute +# define DOUBLE_CONVERSION_HAS_ATTRIBUTE(x) __has_attribute(x) +#else +# define DOUBLE_CONVERSION_HAS_ATTRIBUTE(x) 0 +#endif + +#ifndef DOUBLE_CONVERSION_UNUSED +#if DOUBLE_CONVERSION_HAS_ATTRIBUTE(unused) +#define DOUBLE_CONVERSION_UNUSED __attribute__((unused)) +#else +#define DOUBLE_CONVERSION_UNUSED +#endif +#endif + +#if DOUBLE_CONVERSION_HAS_ATTRIBUTE(uninitialized) +#define DOUBLE_CONVERSION_STACK_UNINITIALIZED __attribute__((uninitialized)) +#else +#define DOUBLE_CONVERSION_STACK_UNINITIALIZED +#endif + +// Double operations detection based on target architecture. +// Linux uses a 80bit wide floating point stack on x86. This induces double +// rounding, which in turn leads to wrong results. +// An easy way to test if the floating-point operations are correct is to +// evaluate: 89255.0/1e22. If the floating-point stack is 64 bits wide then +// the result is equal to 89255e-22. +// The best way to test this, is to create a division-function and to compare +// the output of the division with the expected result. (Inlining must be +// disabled.) +// On Linux,x86 89255e-22 != Div_double(89255.0/1e22) +// +// For example: +/* +// -- in div.c +double Div_double(double x, double y) { return x / y; } + +// -- in main.c +double Div_double(double x, double y); // Forward declaration. + +int main(int argc, char** argv) { + return Div_double(89255.0, 1e22) == 89255e-22; +} +*/ +// Run as follows ./main || echo "correct" +// +// If it prints "correct" then the architecture should be here, in the "correct" section. +#if defined(_M_X64) || defined(__x86_64__) || \ + defined(__ARMEL__) || defined(__avr32__) || defined(_M_ARM) || defined(_M_ARM64) || \ + defined(__hppa__) || defined(__ia64__) || \ + defined(__mips__) || \ + defined(__nios2__) || \ + defined(__powerpc__) || defined(__ppc__) || defined(__ppc64__) || \ + defined(_POWER) || defined(_ARCH_PPC) || defined(_ARCH_PPC64) || \ + defined(__sparc__) || defined(__sparc) || defined(__s390__) || \ + defined(__SH4__) || defined(__alpha__) || \ + defined(_MIPS_ARCH_MIPS32R2) || defined(__ARMEB__) ||\ + defined(__AARCH64EL__) || defined(__aarch64__) || defined(__AARCH64EB__) || \ + defined(__riscv) || defined(__e2k__) || \ + defined(__or1k__) || defined(__arc__) || \ + defined(__microblaze__) || defined(__XTENSA__) || \ + defined(__EMSCRIPTEN__) || defined(__wasm32__) +#define DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS 1 +#elif defined(__mc68000__) || \ + defined(__pnacl__) || defined(__native_client__) +#undef DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS +#elif defined(_M_IX86) || defined(__i386__) || defined(__i386) +#if defined(_WIN32) +// Windows uses a 64bit wide floating point stack. +#define DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS 1 +#else +#undef DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS +#endif // _WIN32 +#else +#error Target architecture was not detected as supported by Double-Conversion. +#endif + +#if defined(_WIN32) && !defined(__MINGW32__) + +typedef signed char int8_t; +typedef unsigned char uint8_t; +typedef short int16_t; // NOLINT +typedef unsigned short uint16_t; // NOLINT +typedef int int32_t; +typedef unsigned int uint32_t; +typedef __int64 int64_t; +typedef unsigned __int64 uint64_t; +// intptr_t and friends are defined in crtdefs.h through stdio.h. + +#else + +#include <stdint.h> + +#endif + +typedef uint16_t uc16; + +// The following macro works on both 32 and 64-bit platforms. +// Usage: instead of writing 0x1234567890123456 +// write DOUBLE_CONVERSION_UINT64_2PART_C(0x12345678,90123456); +#define DOUBLE_CONVERSION_UINT64_2PART_C(a, b) (((static_cast<uint64_t>(a) << 32) + 0x##b##u)) + + +// The expression DOUBLE_CONVERSION_ARRAY_SIZE(a) is a compile-time constant of type +// size_t which represents the number of elements of the given +// array. You should only use DOUBLE_CONVERSION_ARRAY_SIZE on statically allocated +// arrays. +#ifndef DOUBLE_CONVERSION_ARRAY_SIZE +#define DOUBLE_CONVERSION_ARRAY_SIZE(a) \ + ((sizeof(a) / sizeof(*(a))) / \ + static_cast<size_t>(!(sizeof(a) % sizeof(*(a))))) +#endif + +// A macro to disallow the evil copy constructor and operator= functions +// This should be used in the private: declarations for a class +#ifndef DOUBLE_CONVERSION_DISALLOW_COPY_AND_ASSIGN +#define DOUBLE_CONVERSION_DISALLOW_COPY_AND_ASSIGN(TypeName) \ + TypeName(const TypeName&); \ + void operator=(const TypeName&) +#endif + +// A macro to disallow all the implicit constructors, namely the +// default constructor, copy constructor and operator= functions. +// +// This should be used in the private: declarations for a class +// that wants to prevent anyone from instantiating it. This is +// especially useful for classes containing only static methods. +#ifndef DOUBLE_CONVERSION_DISALLOW_IMPLICIT_CONSTRUCTORS +#define DOUBLE_CONVERSION_DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \ + TypeName(); \ + DOUBLE_CONVERSION_DISALLOW_COPY_AND_ASSIGN(TypeName) +#endif + +// ICU PATCH: Wrap in ICU namespace +U_NAMESPACE_BEGIN + +namespace double_conversion { + +inline int StrLength(const char* string) { + size_t length = strlen(string); + DOUBLE_CONVERSION_ASSERT(length == static_cast<size_t>(static_cast<int>(length))); + return static_cast<int>(length); +} + +// This is a simplified version of V8's Vector class. +template <typename T> +class Vector { + public: + Vector() : start_(NULL), length_(0) {} + Vector(T* data, int len) : start_(data), length_(len) { + DOUBLE_CONVERSION_ASSERT(len == 0 || (len > 0 && data != NULL)); + } + + // Returns a vector using the same backing storage as this one, + // spanning from and including 'from', to but not including 'to'. + Vector<T> SubVector(int from, int to) { + DOUBLE_CONVERSION_ASSERT(to <= length_); + DOUBLE_CONVERSION_ASSERT(from < to); + DOUBLE_CONVERSION_ASSERT(0 <= from); + return Vector<T>(start() + from, to - from); + } + + // Returns the length of the vector. + int length() const { return length_; } + + // Returns whether or not the vector is empty. + bool is_empty() const { return length_ == 0; } + + // Returns the pointer to the start of the data in the vector. + T* start() const { return start_; } + + // Access individual vector elements - checks bounds in debug mode. + T& operator[](int index) const { + DOUBLE_CONVERSION_ASSERT(0 <= index && index < length_); + return start_[index]; + } + + T& first() { return start_[0]; } + + T& last() { return start_[length_ - 1]; } + + void pop_back() { + DOUBLE_CONVERSION_ASSERT(!is_empty()); + --length_; + } + + private: + T* start_; + int length_; +}; + + +// Helper class for building result strings in a character buffer. The +// purpose of the class is to use safe operations that checks the +// buffer bounds on all operations in debug mode. +class StringBuilder { + public: + StringBuilder(char* buffer, int buffer_size) + : buffer_(buffer, buffer_size), position_(0) { } + + ~StringBuilder() { if (!is_finalized()) Finalize(); } + + int size() const { return buffer_.length(); } + + // Get the current position in the builder. + int position() const { + DOUBLE_CONVERSION_ASSERT(!is_finalized()); + return position_; + } + + // Reset the position. + void Reset() { position_ = 0; } + + // Add a single character to the builder. It is not allowed to add + // 0-characters; use the Finalize() method to terminate the string + // instead. + void AddCharacter(char c) { + DOUBLE_CONVERSION_ASSERT(c != '\0'); + DOUBLE_CONVERSION_ASSERT(!is_finalized() && position_ < buffer_.length()); + buffer_[position_++] = c; + } + + // Add an entire string to the builder. Uses strlen() internally to + // compute the length of the input string. + void AddString(const char* s) { + AddSubstring(s, StrLength(s)); + } + + // Add the first 'n' characters of the given string 's' to the + // builder. The input string must have enough characters. + void AddSubstring(const char* s, int n) { + DOUBLE_CONVERSION_ASSERT(!is_finalized() && position_ + n < buffer_.length()); + DOUBLE_CONVERSION_ASSERT(static_cast<size_t>(n) <= strlen(s)); + memmove(&buffer_[position_], s, n); + position_ += n; + } + + + // Add character padding to the builder. If count is non-positive, + // nothing is added to the builder. + void AddPadding(char c, int count) { + for (int i = 0; i < count; i++) { + AddCharacter(c); + } + } + + // Finalize the string by 0-terminating it and returning the buffer. + char* Finalize() { + DOUBLE_CONVERSION_ASSERT(!is_finalized() && position_ < buffer_.length()); + buffer_[position_] = '\0'; + // Make sure nobody managed to add a 0-character to the + // buffer while building the string. + DOUBLE_CONVERSION_ASSERT(strlen(buffer_.start()) == static_cast<size_t>(position_)); + position_ = -1; + DOUBLE_CONVERSION_ASSERT(is_finalized()); + return buffer_.start(); + } + + private: + Vector<char> buffer_; + int position_; + + bool is_finalized() const { return position_ < 0; } + + DOUBLE_CONVERSION_DISALLOW_IMPLICIT_CONSTRUCTORS(StringBuilder); +}; + +// The type-based aliasing rule allows the compiler to assume that pointers of +// different types (for some definition of different) never alias each other. +// Thus the following code does not work: +// +// float f = foo(); +// int fbits = *(int*)(&f); +// +// The compiler 'knows' that the int pointer can't refer to f since the types +// don't match, so the compiler may cache f in a register, leaving random data +// in fbits. Using C++ style casts makes no difference, however a pointer to +// char data is assumed to alias any other pointer. This is the 'memcpy +// exception'. +// +// Bit_cast uses the memcpy exception to move the bits from a variable of one +// type of a variable of another type. Of course the end result is likely to +// be implementation dependent. Most compilers (gcc-4.2 and MSVC 2005) +// will completely optimize BitCast away. +// +// There is an additional use for BitCast. +// Recent gccs will warn when they see casts that may result in breakage due to +// the type-based aliasing rule. If you have checked that there is no breakage +// you can use BitCast to cast one pointer type to another. This confuses gcc +// enough that it can no longer see that you have cast one pointer type to +// another thus avoiding the warning. +template <class Dest, class Source> +Dest BitCast(const Source& source) { + // Compile time assertion: sizeof(Dest) == sizeof(Source) + // A compile error here means your Dest and Source have different sizes. +#if __cplusplus >= 201103L + static_assert(sizeof(Dest) == sizeof(Source), + "source and destination size mismatch"); +#else + DOUBLE_CONVERSION_UNUSED + typedef char VerifySizesAreEqual[sizeof(Dest) == sizeof(Source) ? 1 : -1]; +#endif + + Dest dest; + memmove(&dest, &source, sizeof(dest)); + return dest; +} + +template <class Dest, class Source> +Dest BitCast(Source* source) { + return BitCast<Dest>(reinterpret_cast<uintptr_t>(source)); +} + +} // namespace double_conversion + +// ICU PATCH: Close ICU namespace +U_NAMESPACE_END + +#endif // DOUBLE_CONVERSION_UTILS_H_ +#endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING |