mirror of
https://github.com/WinampDesktop/winamp.git
synced 2025-06-16 17:15:46 -04:00
dep: Add rapidyaml
This commit is contained in:
778
dep/rapidyaml/include/c4/memory_util.hpp
Normal file
778
dep/rapidyaml/include/c4/memory_util.hpp
Normal file
@ -0,0 +1,778 @@
|
||||
#ifndef _C4_MEMORY_UTIL_HPP_
|
||||
#define _C4_MEMORY_UTIL_HPP_
|
||||
|
||||
#include "c4/config.hpp"
|
||||
#include "c4/error.hpp"
|
||||
#include "c4/compiler.hpp"
|
||||
#include "c4/cpu.hpp"
|
||||
#ifdef C4_MSVC
|
||||
#include <intrin.h>
|
||||
#endif
|
||||
#include <string.h>
|
||||
|
||||
#if (defined(__GNUC__) && __GNUC__ >= 10) || defined(__has_builtin)
|
||||
#define _C4_USE_LSB_INTRINSIC(which) __has_builtin(which)
|
||||
#define _C4_USE_MSB_INTRINSIC(which) __has_builtin(which)
|
||||
#elif defined(C4_MSVC)
|
||||
#define _C4_USE_LSB_INTRINSIC(which) true
|
||||
#define _C4_USE_MSB_INTRINSIC(which) true
|
||||
#else
|
||||
// let's try our luck
|
||||
#define _C4_USE_LSB_INTRINSIC(which) true
|
||||
#define _C4_USE_MSB_INTRINSIC(which) true
|
||||
#endif
|
||||
|
||||
|
||||
/** @file memory_util.hpp Some memory utilities. */
|
||||
|
||||
namespace c4 {
|
||||
|
||||
C4_SUPPRESS_WARNING_GCC_CLANG_WITH_PUSH("-Wold-style-cast")
|
||||
|
||||
/** set the given memory to zero */
|
||||
C4_ALWAYS_INLINE void mem_zero(void* mem, size_t num_bytes)
|
||||
{
|
||||
memset(mem, 0, num_bytes);
|
||||
}
|
||||
/** set the given memory to zero */
|
||||
template<class T>
|
||||
C4_ALWAYS_INLINE void mem_zero(T* mem, size_t num_elms)
|
||||
{
|
||||
memset(mem, 0, sizeof(T) * num_elms);
|
||||
}
|
||||
/** set the given memory to zero */
|
||||
template<class T>
|
||||
C4_ALWAYS_INLINE void mem_zero(T* mem)
|
||||
{
|
||||
memset(mem, 0, sizeof(T));
|
||||
}
|
||||
|
||||
C4_ALWAYS_INLINE C4_CONST bool mem_overlaps(void const* a, void const* b, size_t sza, size_t szb)
|
||||
{
|
||||
// thanks @timwynants
|
||||
return (((const char*)b + szb) > a && b < ((const char*)a+sza));
|
||||
}
|
||||
|
||||
void mem_repeat(void* dest, void const* pattern, size_t pattern_size, size_t num_times);
|
||||
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
|
||||
template<class T>
|
||||
C4_ALWAYS_INLINE C4_CONST bool is_aligned(T *ptr, uintptr_t alignment=alignof(T))
|
||||
{
|
||||
return (uintptr_t(ptr) & (alignment - uintptr_t(1))) == uintptr_t(0);
|
||||
}
|
||||
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
// least significant bit
|
||||
|
||||
/** @name msb Compute the least significant bit
|
||||
* @note the input value must be nonzero
|
||||
* @note the input type must be unsigned
|
||||
*/
|
||||
/** @{ */
|
||||
|
||||
// https://graphics.stanford.edu/~seander/bithacks.html#ZerosOnRightLinear
|
||||
#define _c4_lsb_fallback \
|
||||
unsigned c = 0; \
|
||||
v = (v ^ (v - 1)) >> 1; /* Set v's trailing 0s to 1s and zero rest */ \
|
||||
for(; v; ++c) \
|
||||
v >>= 1; \
|
||||
return (unsigned) c
|
||||
|
||||
// u8
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto lsb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 1u, unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_LSB_INTRINSIC(__builtin_ctz)
|
||||
// upcast to use the intrinsic, it's cheaper.
|
||||
#ifdef C4_MSVC
|
||||
#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanForward(&bit, (unsigned long)v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
#else
|
||||
return (unsigned)__builtin_ctz((unsigned)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
// u16
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto lsb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 2u, unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_LSB_INTRINSIC(__builtin_ctz)
|
||||
// upcast to use the intrinsic, it's cheaper.
|
||||
// Then remember that the upcast makes it to 31bits
|
||||
#ifdef C4_MSVC
|
||||
#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanForward(&bit, (unsigned long)v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
#else
|
||||
return (unsigned)__builtin_ctz((unsigned)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
// u32
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto lsb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 4u, unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_LSB_INTRINSIC(__builtin_ctz)
|
||||
#ifdef C4_MSVC
|
||||
#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanForward(&bit, v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
#else
|
||||
return (unsigned)__builtin_ctz((unsigned)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
// u64 in 64bits
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto lsb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 8u && sizeof(unsigned long) == 8u, unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_LSB_INTRINSIC(__builtin_ctzl)
|
||||
#if defined(C4_MSVC)
|
||||
#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanForward64(&bit, v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
#else
|
||||
return (unsigned)__builtin_ctzl((unsigned long)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
// u64 in 32bits
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto lsb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 8u && sizeof(unsigned long long) == 8u && sizeof(unsigned long) != sizeof(unsigned long long), unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_LSB_INTRINSIC(__builtin_ctzll)
|
||||
#if defined(C4_MSVC)
|
||||
#if !defined(C4_CPU_X86) && !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanForward64(&bit, v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
#else
|
||||
return (unsigned)__builtin_ctzll((unsigned long long)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_lsb_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
#undef _c4_lsb_fallback
|
||||
|
||||
/** @} */
|
||||
|
||||
|
||||
namespace detail {
|
||||
template<class I, I val, unsigned num_bits, bool finished> struct _lsb11;
|
||||
template<class I, I val, unsigned num_bits>
|
||||
struct _lsb11<I, val, num_bits, false>
|
||||
{
|
||||
enum : unsigned { num = _lsb11<I, (val>>1), num_bits+I(1), (((val>>1)&I(1))!=I(0))>::num };
|
||||
};
|
||||
template<class I, I val, unsigned num_bits>
|
||||
struct _lsb11<I, val, num_bits, true>
|
||||
{
|
||||
enum : unsigned { num = num_bits };
|
||||
};
|
||||
} // namespace detail
|
||||
|
||||
|
||||
/** TMP version of lsb(); this needs to be implemented with template
|
||||
* meta-programming because C++11 cannot use a constexpr function with
|
||||
* local variables
|
||||
* @see lsb */
|
||||
template<class I, I number>
|
||||
struct lsb11
|
||||
{
|
||||
static_assert(number != 0, "lsb: number must be nonzero");
|
||||
enum : unsigned { value = detail::_lsb11<I, number, 0, ((number&I(1))!=I(0))>::num};
|
||||
};
|
||||
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
// most significant bit
|
||||
|
||||
|
||||
/** @name msb Compute the most significant bit
|
||||
* @note the input value must be nonzero
|
||||
* @note the input type must be unsigned
|
||||
*/
|
||||
/** @{ */
|
||||
|
||||
|
||||
#define _c4_msb8_fallback \
|
||||
unsigned n = 0; \
|
||||
if(v & I(0xf0)) v >>= 4, n |= I(4); \
|
||||
if(v & I(0x0c)) v >>= 2, n |= I(2); \
|
||||
if(v & I(0x02)) v >>= 1, n |= I(1); \
|
||||
return n
|
||||
|
||||
#define _c4_msb16_fallback \
|
||||
unsigned n = 0; \
|
||||
if(v & I(0xff00)) v >>= 8, n |= I(8); \
|
||||
if(v & I(0x00f0)) v >>= 4, n |= I(4); \
|
||||
if(v & I(0x000c)) v >>= 2, n |= I(2); \
|
||||
if(v & I(0x0002)) v >>= 1, n |= I(1); \
|
||||
return n
|
||||
|
||||
#define _c4_msb32_fallback \
|
||||
unsigned n = 0; \
|
||||
if(v & I(0xffff0000)) v >>= 16, n |= 16; \
|
||||
if(v & I(0x0000ff00)) v >>= 8, n |= 8; \
|
||||
if(v & I(0x000000f0)) v >>= 4, n |= 4; \
|
||||
if(v & I(0x0000000c)) v >>= 2, n |= 2; \
|
||||
if(v & I(0x00000002)) v >>= 1, n |= 1; \
|
||||
return n
|
||||
|
||||
#define _c4_msb64_fallback \
|
||||
unsigned n = 0; \
|
||||
if(v & I(0xffffffff00000000)) v >>= 32, n |= I(32); \
|
||||
if(v & I(0x00000000ffff0000)) v >>= 16, n |= I(16); \
|
||||
if(v & I(0x000000000000ff00)) v >>= 8, n |= I(8); \
|
||||
if(v & I(0x00000000000000f0)) v >>= 4, n |= I(4); \
|
||||
if(v & I(0x000000000000000c)) v >>= 2, n |= I(2); \
|
||||
if(v & I(0x0000000000000002)) v >>= 1, n |= I(1); \
|
||||
return n
|
||||
|
||||
|
||||
// u8
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto msb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 1u, unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_MSB_INTRINSIC(__builtin_clz)
|
||||
// upcast to use the intrinsic, it's cheaper.
|
||||
// Then remember that the upcast makes it to 31bits
|
||||
#ifdef C4_MSVC
|
||||
#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanReverse(&bit, (unsigned long)v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_msb8_fallback;
|
||||
#endif
|
||||
#else
|
||||
return 31u - (unsigned)__builtin_clz((unsigned)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_msb8_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
// u16
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto msb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 2u, unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_MSB_INTRINSIC(__builtin_clz)
|
||||
// upcast to use the intrinsic, it's cheaper.
|
||||
// Then remember that the upcast makes it to 31bits
|
||||
#ifdef C4_MSVC
|
||||
#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanReverse(&bit, (unsigned long)v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_msb16_fallback;
|
||||
#endif
|
||||
#else
|
||||
return 31u - (unsigned)__builtin_clz((unsigned)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_msb16_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
// u32
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto msb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 4u, unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_MSB_INTRINSIC(__builtin_clz)
|
||||
#ifdef C4_MSVC
|
||||
#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanReverse(&bit, v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_msb32_fallback;
|
||||
#endif
|
||||
#else
|
||||
return 31u - (unsigned)__builtin_clz((unsigned)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_msb32_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
// u64 in 64bits
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto msb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 8u && sizeof(unsigned long) == 8u, unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_MSB_INTRINSIC(__builtin_clzl)
|
||||
#ifdef C4_MSVC
|
||||
#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanReverse64(&bit, v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_msb64_fallback;
|
||||
#endif
|
||||
#else
|
||||
return 63u - (unsigned)__builtin_clzl((unsigned long)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_msb64_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
// u64 in 32bits
|
||||
template<class I>
|
||||
C4_CONSTEXPR14
|
||||
auto msb(I v) noexcept
|
||||
-> typename std::enable_if<sizeof(I) == 8u && sizeof(unsigned long long) == 8u && sizeof(unsigned long) != sizeof(unsigned long long), unsigned>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_unsigned<I>::value);
|
||||
C4_ASSERT(v != 0);
|
||||
#if _C4_USE_MSB_INTRINSIC(__builtin_clzll)
|
||||
#ifdef C4_MSVC
|
||||
#if !defined(C4_CPU_X86) && !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
|
||||
unsigned long bit;
|
||||
_BitScanReverse64(&bit, v);
|
||||
return bit;
|
||||
#else
|
||||
_c4_msb64_fallback;
|
||||
#endif
|
||||
#else
|
||||
return 63u - (unsigned)__builtin_clzll((unsigned long long)v);
|
||||
#endif
|
||||
#else
|
||||
_c4_msb64_fallback;
|
||||
#endif
|
||||
}
|
||||
|
||||
#undef _c4_msb8_fallback
|
||||
#undef _c4_msb16_fallback
|
||||
#undef _c4_msb32_fallback
|
||||
#undef _c4_msb64_fallback
|
||||
|
||||
/** @} */
|
||||
|
||||
|
||||
namespace detail {
|
||||
template<class I, I val, I num_bits, bool finished> struct _msb11;
|
||||
template<class I, I val, I num_bits>
|
||||
struct _msb11< I, val, num_bits, false>
|
||||
{
|
||||
enum : unsigned { num = _msb11<I, (val>>1), num_bits+I(1), ((val>>1)==I(0))>::num };
|
||||
};
|
||||
template<class I, I val, I num_bits>
|
||||
struct _msb11<I, val, num_bits, true>
|
||||
{
|
||||
static_assert(val == 0, "bad implementation");
|
||||
enum : unsigned { num = (unsigned)(num_bits-1) };
|
||||
};
|
||||
} // namespace detail
|
||||
|
||||
|
||||
/** TMP version of msb(); this needs to be implemented with template
|
||||
* meta-programming because C++11 cannot use a constexpr function with
|
||||
* local variables
|
||||
* @see msb */
|
||||
template<class I, I number>
|
||||
struct msb11
|
||||
{
|
||||
enum : unsigned { value = detail::_msb11<I, number, 0, (number==I(0))>::num };
|
||||
};
|
||||
|
||||
|
||||
|
||||
#undef _C4_USE_LSB_INTRINSIC
|
||||
#undef _C4_USE_MSB_INTRINSIC
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
|
||||
// there is an implicit conversion below; it happens when E or B are
|
||||
// narrower than int, and thus any operation will upcast the result to
|
||||
// int, and then downcast to assign
|
||||
C4_SUPPRESS_WARNING_GCC_CLANG_WITH_PUSH("-Wconversion")
|
||||
|
||||
/** integer power; this function is constexpr-14 because of the local
|
||||
* variables */
|
||||
template<class B, class E>
|
||||
C4_CONSTEXPR14 C4_CONST auto ipow(B base, E exponent) noexcept -> typename std::enable_if<std::is_signed<E>::value, B>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_integral<E>::value);
|
||||
B r = B(1);
|
||||
if(exponent >= 0)
|
||||
{
|
||||
for(E e = 0; e < exponent; ++e)
|
||||
r *= base;
|
||||
}
|
||||
else
|
||||
{
|
||||
exponent *= E(-1);
|
||||
for(E e = 0; e < exponent; ++e)
|
||||
r /= base;
|
||||
}
|
||||
return r;
|
||||
}
|
||||
|
||||
/** integer power; this function is constexpr-14 because of the local
|
||||
* variables */
|
||||
template<class B, B base, class E>
|
||||
C4_CONSTEXPR14 C4_CONST auto ipow(E exponent) noexcept -> typename std::enable_if<std::is_signed<E>::value, B>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_integral<E>::value);
|
||||
B r = B(1);
|
||||
if(exponent >= 0)
|
||||
{
|
||||
for(E e = 0; e < exponent; ++e)
|
||||
r *= base;
|
||||
}
|
||||
else
|
||||
{
|
||||
exponent *= E(-1);
|
||||
for(E e = 0; e < exponent; ++e)
|
||||
r /= base;
|
||||
}
|
||||
return r;
|
||||
}
|
||||
|
||||
/** integer power; this function is constexpr-14 because of the local
|
||||
* variables */
|
||||
template<class B, class Base, Base base, class E>
|
||||
C4_CONSTEXPR14 C4_CONST auto ipow(E exponent) noexcept -> typename std::enable_if<std::is_signed<E>::value, B>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_integral<E>::value);
|
||||
B r = B(1);
|
||||
B bbase = B(base);
|
||||
if(exponent >= 0)
|
||||
{
|
||||
for(E e = 0; e < exponent; ++e)
|
||||
r *= bbase;
|
||||
}
|
||||
else
|
||||
{
|
||||
exponent *= E(-1);
|
||||
for(E e = 0; e < exponent; ++e)
|
||||
r /= bbase;
|
||||
}
|
||||
return r;
|
||||
}
|
||||
|
||||
/** integer power; this function is constexpr-14 because of the local
|
||||
* variables */
|
||||
template<class B, class E>
|
||||
C4_CONSTEXPR14 C4_CONST auto ipow(B base, E exponent) noexcept -> typename std::enable_if<!std::is_signed<E>::value, B>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_integral<E>::value);
|
||||
B r = B(1);
|
||||
for(E e = 0; e < exponent; ++e)
|
||||
r *= base;
|
||||
return r;
|
||||
}
|
||||
|
||||
/** integer power; this function is constexpr-14 because of the local
|
||||
* variables */
|
||||
template<class B, B base, class E>
|
||||
C4_CONSTEXPR14 C4_CONST auto ipow(E exponent) noexcept -> typename std::enable_if<!std::is_signed<E>::value, B>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_integral<E>::value);
|
||||
B r = B(1);
|
||||
for(E e = 0; e < exponent; ++e)
|
||||
r *= base;
|
||||
return r;
|
||||
}
|
||||
/** integer power; this function is constexpr-14 because of the local
|
||||
* variables */
|
||||
template<class B, class Base, Base base, class E>
|
||||
C4_CONSTEXPR14 C4_CONST auto ipow(E exponent) noexcept -> typename std::enable_if<!std::is_signed<E>::value, B>::type
|
||||
{
|
||||
C4_STATIC_ASSERT(std::is_integral<E>::value);
|
||||
B r = B(1);
|
||||
B bbase = B(base);
|
||||
for(E e = 0; e < exponent; ++e)
|
||||
r *= bbase;
|
||||
return r;
|
||||
}
|
||||
|
||||
C4_SUPPRESS_WARNING_GCC_CLANG_POP
|
||||
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
|
||||
/** return a mask with all bits set [first_bit,last_bit[; this function
|
||||
* is constexpr-14 because of the local variables */
|
||||
template<class I>
|
||||
C4_CONSTEXPR14 I contiguous_mask(I first_bit, I last_bit)
|
||||
{
|
||||
I r = 0;
|
||||
for(I i = first_bit; i < last_bit; ++i)
|
||||
{
|
||||
r |= (I(1) << i);
|
||||
}
|
||||
return r;
|
||||
}
|
||||
|
||||
|
||||
namespace detail {
|
||||
|
||||
template<class I, I val, I first, I last, bool finished>
|
||||
struct _ctgmsk11;
|
||||
|
||||
template<class I, I val, I first, I last>
|
||||
struct _ctgmsk11< I, val, first, last, true>
|
||||
{
|
||||
enum : I { value = _ctgmsk11<I, val|(I(1)<<first), first+I(1), last, (first+1!=last)>::value };
|
||||
};
|
||||
|
||||
template<class I, I val, I first, I last>
|
||||
struct _ctgmsk11< I, val, first, last, false>
|
||||
{
|
||||
enum : I { value = val };
|
||||
};
|
||||
|
||||
} // namespace detail
|
||||
|
||||
|
||||
/** TMP version of contiguous_mask(); this needs to be implemented with template
|
||||
* meta-programming because C++11 cannot use a constexpr function with
|
||||
* local variables
|
||||
* @see contiguous_mask */
|
||||
template<class I, I first_bit, I last_bit>
|
||||
struct contiguous_mask11
|
||||
{
|
||||
enum : I { value = detail::_ctgmsk11<I, I(0), first_bit, last_bit, (first_bit!=last_bit)>::value };
|
||||
};
|
||||
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
//-----------------------------------------------------------------------------
|
||||
/** use Empty Base Class Optimization to reduce the size of a pair of
|
||||
* potentially empty types*/
|
||||
|
||||
namespace detail {
|
||||
typedef enum {
|
||||
tpc_same,
|
||||
tpc_same_empty,
|
||||
tpc_both_empty,
|
||||
tpc_first_empty,
|
||||
tpc_second_empty,
|
||||
tpc_general
|
||||
} TightPairCase_e;
|
||||
|
||||
template<class First, class Second>
|
||||
constexpr TightPairCase_e tpc_which_case()
|
||||
{
|
||||
return std::is_same<First, Second>::value ?
|
||||
std::is_empty<First>::value ?
|
||||
tpc_same_empty
|
||||
:
|
||||
tpc_same
|
||||
:
|
||||
std::is_empty<First>::value && std::is_empty<Second>::value ?
|
||||
tpc_both_empty
|
||||
:
|
||||
std::is_empty<First>::value ?
|
||||
tpc_first_empty
|
||||
:
|
||||
std::is_empty<Second>::value ?
|
||||
tpc_second_empty
|
||||
:
|
||||
tpc_general
|
||||
;
|
||||
}
|
||||
|
||||
template<class First, class Second, TightPairCase_e Case>
|
||||
struct tight_pair
|
||||
{
|
||||
private:
|
||||
|
||||
First m_first;
|
||||
Second m_second;
|
||||
|
||||
public:
|
||||
|
||||
using first_type = First;
|
||||
using second_type = Second;
|
||||
|
||||
tight_pair() : m_first(), m_second() {}
|
||||
tight_pair(First const& f, Second const& s) : m_first(f), m_second(s) {}
|
||||
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First & first () { return m_first; }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First const& first () const { return m_first; }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second & second() { return m_second; }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second const& second() const { return m_second; }
|
||||
};
|
||||
|
||||
template<class First, class Second>
|
||||
struct tight_pair<First, Second, tpc_same_empty> : public First
|
||||
{
|
||||
static_assert(std::is_same<First, Second>::value, "bad implementation");
|
||||
|
||||
using first_type = First;
|
||||
using second_type = Second;
|
||||
|
||||
tight_pair() : First() {}
|
||||
tight_pair(First const& f, Second const& /*s*/) : First(f) {}
|
||||
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First & first () { return static_cast<First &>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First const& first () const { return static_cast<First const&>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second & second() { return reinterpret_cast<Second &>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second const& second() const { return reinterpret_cast<Second const&>(*this); }
|
||||
};
|
||||
|
||||
template<class First, class Second>
|
||||
struct tight_pair<First, Second, tpc_both_empty> : public First, public Second
|
||||
{
|
||||
using first_type = First;
|
||||
using second_type = Second;
|
||||
|
||||
tight_pair() : First(), Second() {}
|
||||
tight_pair(First const& f, Second const& s) : First(f), Second(s) {}
|
||||
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First & first () { return static_cast<First &>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First const& first () const { return static_cast<First const&>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second & second() { return static_cast<Second &>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second const& second() const { return static_cast<Second const&>(*this); }
|
||||
};
|
||||
|
||||
template<class First, class Second>
|
||||
struct tight_pair<First, Second, tpc_same> : public First
|
||||
{
|
||||
Second m_second;
|
||||
|
||||
using first_type = First;
|
||||
using second_type = Second;
|
||||
|
||||
tight_pair() : First() {}
|
||||
tight_pair(First const& f, Second const& s) : First(f), m_second(s) {}
|
||||
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First & first () { return static_cast<First &>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First const& first () const { return static_cast<First const&>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second & second() { return m_second; }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second const& second() const { return m_second; }
|
||||
};
|
||||
|
||||
template<class First, class Second>
|
||||
struct tight_pair<First, Second, tpc_first_empty> : public First
|
||||
{
|
||||
Second m_second;
|
||||
|
||||
using first_type = First;
|
||||
using second_type = Second;
|
||||
|
||||
tight_pair() : First(), m_second() {}
|
||||
tight_pair(First const& f, Second const& s) : First(f), m_second(s) {}
|
||||
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First & first () { return static_cast<First &>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First const& first () const { return static_cast<First const&>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second & second() { return m_second; }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second const& second() const { return m_second; }
|
||||
};
|
||||
|
||||
template<class First, class Second>
|
||||
struct tight_pair<First, Second, tpc_second_empty> : public Second
|
||||
{
|
||||
First m_first;
|
||||
|
||||
using first_type = First;
|
||||
using second_type = Second;
|
||||
|
||||
tight_pair() : Second(), m_first() {}
|
||||
tight_pair(First const& f, Second const& s) : Second(s), m_first(f) {}
|
||||
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First & first () { return m_first; }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 First const& first () const { return m_first; }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second & second() { return static_cast<Second &>(*this); }
|
||||
C4_ALWAYS_INLINE C4_CONSTEXPR14 Second const& second() const { return static_cast<Second const&>(*this); }
|
||||
};
|
||||
|
||||
} // namespace detail
|
||||
|
||||
template<class First, class Second>
|
||||
using tight_pair = detail::tight_pair<First, Second, detail::tpc_which_case<First,Second>()>;
|
||||
|
||||
C4_SUPPRESS_WARNING_GCC_CLANG_POP
|
||||
|
||||
} // namespace c4
|
||||
|
||||
#endif /* _C4_MEMORY_UTIL_HPP_ */
|
Reference in New Issue
Block a user