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common: Merge uint128 to a single header file with inlines.

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This commit is contained in:
bunnei 2021-02-15 14:46:04 -08:00
parent ed543c4d5c
commit 0a91599aec
4 changed files with 84 additions and 135 deletions
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58
src/common/x64/native_clock.cpp
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@ -8,68 +8,10 @@
#include <mutex>
#include <thread>
#ifdef _MSC_VER
#include <intrin.h>
#pragma intrinsic(__umulh)
#pragma intrinsic(_udiv128)
#else
#include <x86intrin.h>
#endif
#include "common/atomic_ops.h"
#include "common/uint128.h"
#include "common/x64/native_clock.h"
namespace {
[[nodiscard]] u64 GetFixedPoint64Factor(u64 numerator, u64 divisor) {
#ifdef __SIZEOF_INT128__
const auto base = static_cast<unsigned __int128>(numerator) << 64ULL;
return static_cast<u64>(base / divisor);
#elif defined(_M_X64) || defined(_M_ARM64)
std::array<u64, 2> r = {0, numerator};
u64 remainder;
#if _MSC_VER < 1923
return udiv128(r[1], r[0], divisor, &remainder);
#else
return _udiv128(r[1], r[0], divisor, &remainder);
#endif
#else
// This one is bit more inaccurate.
return MultiplyAndDivide64(std::numeric_limits<u64>::max(), numerator, divisor);
#endif
}
[[nodiscard]] u64 MultiplyHigh(u64 a, u64 b) {
#ifdef __SIZEOF_INT128__
return (static_cast<unsigned __int128>(a) * static_cast<unsigned __int128>(b)) >> 64;
#elif defined(_M_X64) || defined(_M_ARM64)
return __umulh(a, b); // MSVC
#else
// Generic fallback
const u64 a_lo = u32(a);
const u64 a_hi = a >> 32;
const u64 b_lo = u32(b);
const u64 b_hi = b >> 32;
const u64 a_x_b_hi = a_hi * b_hi;
const u64 a_x_b_mid = a_hi * b_lo;
const u64 b_x_a_mid = b_hi * a_lo;
const u64 a_x_b_lo = a_lo * b_lo;
const u64 carry_bit = (static_cast<u64>(static_cast<u32>(a_x_b_mid)) +
static_cast<u64>(static_cast<u32>(b_x_a_mid)) + (a_x_b_lo >> 32)) >>
32;
const u64 multhi = a_x_b_hi + (a_x_b_mid >> 32) + (b_x_a_mid >> 32) + carry_bit;
return multhi;
#endif
}
} // namespace
namespace Common {
u64 EstimateRDTSCFrequency() {