mirror of
https://github.com/RetroDECK/Duckstation.git
synced 2024-12-11 06:55:38 +00:00
779 lines
24 KiB
C++
779 lines
24 KiB
C++
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#ifndef _C4_MEMORY_UTIL_HPP_
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#define _C4_MEMORY_UTIL_HPP_
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#include "c4/config.hpp"
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#include "c4/error.hpp"
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#include "c4/compiler.hpp"
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#include "c4/cpu.hpp"
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#ifdef C4_MSVC
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#include <intrin.h>
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#endif
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#include <string.h>
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#if (defined(__GNUC__) && __GNUC__ >= 10) || defined(__has_builtin)
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#define _C4_USE_LSB_INTRINSIC(which) __has_builtin(which)
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#define _C4_USE_MSB_INTRINSIC(which) __has_builtin(which)
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#elif defined(C4_MSVC)
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#define _C4_USE_LSB_INTRINSIC(which) true
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#define _C4_USE_MSB_INTRINSIC(which) true
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#else
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// let's try our luck
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#define _C4_USE_LSB_INTRINSIC(which) true
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#define _C4_USE_MSB_INTRINSIC(which) true
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#endif
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/** @file memory_util.hpp Some memory utilities. */
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namespace c4 {
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C4_SUPPRESS_WARNING_GCC_CLANG_WITH_PUSH("-Wold-style-cast")
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/** set the given memory to zero */
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C4_ALWAYS_INLINE void mem_zero(void* mem, size_t num_bytes)
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{
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memset(mem, 0, num_bytes);
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}
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/** set the given memory to zero */
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template<class T>
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C4_ALWAYS_INLINE void mem_zero(T* mem, size_t num_elms)
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{
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memset(mem, 0, sizeof(T) * num_elms);
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}
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/** set the given memory to zero */
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template<class T>
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C4_ALWAYS_INLINE void mem_zero(T* mem)
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{
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memset(mem, 0, sizeof(T));
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}
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C4_ALWAYS_INLINE C4_CONST bool mem_overlaps(void const* a, void const* b, size_t sza, size_t szb)
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{
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// thanks @timwynants
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return (((const char*)b + szb) > a && b < ((const char*)a+sza));
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}
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void mem_repeat(void* dest, void const* pattern, size_t pattern_size, size_t num_times);
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//-----------------------------------------------------------------------------
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//-----------------------------------------------------------------------------
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//-----------------------------------------------------------------------------
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template<class T>
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C4_ALWAYS_INLINE C4_CONST bool is_aligned(T *ptr, uintptr_t alignment=alignof(T))
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{
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return (uintptr_t(ptr) & (alignment - uintptr_t(1))) == uintptr_t(0);
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}
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//-----------------------------------------------------------------------------
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//-----------------------------------------------------------------------------
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//-----------------------------------------------------------------------------
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// least significant bit
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/** @name msb Compute the least significant bit
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* @note the input value must be nonzero
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* @note the input type must be unsigned
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*/
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/** @{ */
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// https://graphics.stanford.edu/~seander/bithacks.html#ZerosOnRightLinear
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#define _c4_lsb_fallback \
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unsigned c = 0; \
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v = (v ^ (v - 1)) >> 1; /* Set v's trailing 0s to 1s and zero rest */ \
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for(; v; ++c) \
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v >>= 1; \
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return (unsigned) c
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// u8
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template<class I>
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C4_CONSTEXPR14
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auto lsb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 1u, unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_LSB_INTRINSIC(__builtin_ctz)
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// upcast to use the intrinsic, it's cheaper.
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#ifdef C4_MSVC
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#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanForward(&bit, (unsigned long)v);
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return bit;
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#else
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_c4_lsb_fallback;
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#endif
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#else
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return (unsigned)__builtin_ctz((unsigned)v);
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#endif
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#else
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_c4_lsb_fallback;
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#endif
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}
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// u16
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template<class I>
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C4_CONSTEXPR14
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auto lsb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 2u, unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_LSB_INTRINSIC(__builtin_ctz)
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// upcast to use the intrinsic, it's cheaper.
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// Then remember that the upcast makes it to 31bits
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#ifdef C4_MSVC
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#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanForward(&bit, (unsigned long)v);
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return bit;
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#else
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_c4_lsb_fallback;
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#endif
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#else
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return (unsigned)__builtin_ctz((unsigned)v);
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#endif
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#else
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_c4_lsb_fallback;
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#endif
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}
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// u32
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template<class I>
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C4_CONSTEXPR14
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auto lsb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 4u, unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_LSB_INTRINSIC(__builtin_ctz)
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#ifdef C4_MSVC
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#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanForward(&bit, v);
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return bit;
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#else
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_c4_lsb_fallback;
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#endif
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#else
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return (unsigned)__builtin_ctz((unsigned)v);
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#endif
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#else
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_c4_lsb_fallback;
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#endif
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}
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// u64 in 64bits
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template<class I>
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C4_CONSTEXPR14
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auto lsb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 8u && sizeof(unsigned long) == 8u, unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_LSB_INTRINSIC(__builtin_ctzl)
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#if defined(C4_MSVC)
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#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanForward64(&bit, v);
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return bit;
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#else
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_c4_lsb_fallback;
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#endif
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#else
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return (unsigned)__builtin_ctzl((unsigned long)v);
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#endif
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#else
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_c4_lsb_fallback;
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#endif
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}
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// u64 in 32bits
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template<class I>
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C4_CONSTEXPR14
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auto lsb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 8u && sizeof(unsigned long long) == 8u && sizeof(unsigned long) != sizeof(unsigned long long), unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_LSB_INTRINSIC(__builtin_ctzll)
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#if defined(C4_MSVC)
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#if !defined(C4_CPU_X86) && !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanForward64(&bit, v);
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return bit;
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#else
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_c4_lsb_fallback;
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#endif
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#else
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return (unsigned)__builtin_ctzll((unsigned long long)v);
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#endif
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#else
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_c4_lsb_fallback;
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#endif
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}
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#undef _c4_lsb_fallback
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/** @} */
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namespace detail {
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template<class I, I val, unsigned num_bits, bool finished> struct _lsb11;
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template<class I, I val, unsigned num_bits>
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struct _lsb11<I, val, num_bits, false>
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{
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enum : unsigned { num = _lsb11<I, (val>>1), num_bits+I(1), (((val>>1)&I(1))!=I(0))>::num };
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};
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template<class I, I val, unsigned num_bits>
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struct _lsb11<I, val, num_bits, true>
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{
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enum : unsigned { num = num_bits };
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};
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} // namespace detail
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/** TMP version of lsb(); this needs to be implemented with template
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* meta-programming because C++11 cannot use a constexpr function with
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* local variables
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* @see lsb */
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template<class I, I number>
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struct lsb11
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{
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static_assert(number != 0, "lsb: number must be nonzero");
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enum : unsigned { value = detail::_lsb11<I, number, 0, ((number&I(1))!=I(0))>::num};
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};
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//-----------------------------------------------------------------------------
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//-----------------------------------------------------------------------------
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//-----------------------------------------------------------------------------
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// most significant bit
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/** @name msb Compute the most significant bit
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* @note the input value must be nonzero
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* @note the input type must be unsigned
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*/
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/** @{ */
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#define _c4_msb8_fallback \
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unsigned n = 0; \
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if(v & I(0xf0)) v >>= 4, n |= I(4); \
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if(v & I(0x0c)) v >>= 2, n |= I(2); \
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if(v & I(0x02)) v >>= 1, n |= I(1); \
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return n
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#define _c4_msb16_fallback \
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unsigned n = 0; \
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if(v & I(0xff00)) v >>= 8, n |= I(8); \
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if(v & I(0x00f0)) v >>= 4, n |= I(4); \
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if(v & I(0x000c)) v >>= 2, n |= I(2); \
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if(v & I(0x0002)) v >>= 1, n |= I(1); \
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return n
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#define _c4_msb32_fallback \
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unsigned n = 0; \
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if(v & I(0xffff0000)) v >>= 16, n |= 16; \
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if(v & I(0x0000ff00)) v >>= 8, n |= 8; \
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if(v & I(0x000000f0)) v >>= 4, n |= 4; \
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if(v & I(0x0000000c)) v >>= 2, n |= 2; \
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if(v & I(0x00000002)) v >>= 1, n |= 1; \
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return n
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#define _c4_msb64_fallback \
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unsigned n = 0; \
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if(v & I(0xffffffff00000000)) v >>= 32, n |= I(32); \
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if(v & I(0x00000000ffff0000)) v >>= 16, n |= I(16); \
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if(v & I(0x000000000000ff00)) v >>= 8, n |= I(8); \
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if(v & I(0x00000000000000f0)) v >>= 4, n |= I(4); \
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if(v & I(0x000000000000000c)) v >>= 2, n |= I(2); \
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if(v & I(0x0000000000000002)) v >>= 1, n |= I(1); \
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return n
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// u8
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template<class I>
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C4_CONSTEXPR14
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auto msb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 1u, unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_MSB_INTRINSIC(__builtin_clz)
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// upcast to use the intrinsic, it's cheaper.
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// Then remember that the upcast makes it to 31bits
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#ifdef C4_MSVC
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#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanReverse(&bit, (unsigned long)v);
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return bit;
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#else
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_c4_msb8_fallback;
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#endif
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#else
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return 31u - (unsigned)__builtin_clz((unsigned)v);
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#endif
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#else
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_c4_msb8_fallback;
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#endif
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}
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// u16
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template<class I>
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C4_CONSTEXPR14
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auto msb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 2u, unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_MSB_INTRINSIC(__builtin_clz)
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// upcast to use the intrinsic, it's cheaper.
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// Then remember that the upcast makes it to 31bits
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#ifdef C4_MSVC
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#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanReverse(&bit, (unsigned long)v);
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return bit;
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#else
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_c4_msb16_fallback;
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#endif
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#else
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return 31u - (unsigned)__builtin_clz((unsigned)v);
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#endif
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#else
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_c4_msb16_fallback;
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#endif
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}
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// u32
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template<class I>
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C4_CONSTEXPR14
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auto msb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 4u, unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_MSB_INTRINSIC(__builtin_clz)
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#ifdef C4_MSVC
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#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanReverse(&bit, v);
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return bit;
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#else
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_c4_msb32_fallback;
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#endif
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#else
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return 31u - (unsigned)__builtin_clz((unsigned)v);
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#endif
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#else
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_c4_msb32_fallback;
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#endif
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}
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// u64 in 64bits
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template<class I>
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C4_CONSTEXPR14
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auto msb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 8u && sizeof(unsigned long) == 8u, unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_MSB_INTRINSIC(__builtin_clzl)
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#ifdef C4_MSVC
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#if !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanReverse64(&bit, v);
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return bit;
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#else
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_c4_msb64_fallback;
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#endif
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#else
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return 63u - (unsigned)__builtin_clzl((unsigned long)v);
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#endif
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#else
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_c4_msb64_fallback;
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#endif
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}
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// u64 in 32bits
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template<class I>
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C4_CONSTEXPR14
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auto msb(I v) noexcept
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-> typename std::enable_if<sizeof(I) == 8u && sizeof(unsigned long long) == 8u && sizeof(unsigned long) != sizeof(unsigned long long), unsigned>::type
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{
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C4_STATIC_ASSERT(std::is_unsigned<I>::value);
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C4_ASSERT(v != 0);
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#if _C4_USE_MSB_INTRINSIC(__builtin_clzll)
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#ifdef C4_MSVC
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#if !defined(C4_CPU_X86) && !defined(C4_CPU_ARM64) && !defined(C4_CPU_ARM)
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unsigned long bit;
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_BitScanReverse64(&bit, v);
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return bit;
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#else
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_c4_msb64_fallback;
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#endif
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||
|
#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_ */
|