Use u128 on Clock Cycles calculation.

This commit is contained in:
Fernando Sahmkow 2019-02-15 20:04:11 -04:00 committed by FernandoS27
parent 3ea48e8ebe
commit ecccfe0337
5 changed files with 32 additions and 27 deletions

View file

@ -1,7 +1,25 @@
#ifdef _MSC_VER
#include <intrin.h>
#pragma intrinsic(_umul128)
#endif
#include "common/uint128.h"
namespace Common {
u128 Multiply64Into128(u64 a, u64 b) {
#ifdef _MSC_VER
u128 result;
result[0] = _umul128(a, b, &result[1]);
#else
unsigned __int128 tmp = a;
tmp *= b;
u128 result;
std::memcpy(&result, &tmp, sizeof(u128));
#endif
return result;
}
std::pair<u64, u64> udiv128(u128 dividend, u64 divisor) {
std::pair<u64, u64> Divide128On64(u128 dividend, u64 divisor) {
u64 remainder = dividend[0] % divisor;
u64 accum = dividend[0] / divisor;
if (dividend[1] == 0)
@ -12,6 +30,10 @@ std::pair<u64, u64> udiv128(u128 dividend, u64 divisor) {
u64 second_segment = (first_segment % divisor) << 32;
accum += (second_segment / divisor);
remainder += second_segment % divisor;
if (remainder >= divisor) {
accum++;
remainder -= divisor;
}
return {accum, remainder};
}

View file

@ -1,30 +1,13 @@
#include <array>
#include <cstdint>
#include <utility>
#include <cstring>
#include <utility>
#include "common/common_types.h"
namespace Common {
#ifdef _MSC_VER
#include <intrin.h>
u128 Multiply64Into128(u64 a, u64 b);
#pragma intrinsic(_umul128)
#endif
inline u128 umul128(u64 a, u64 b) {
#ifdef _MSC_VER
u128 result;
result[0] = _umul128(a, b, &result[1]);
#else
unsigned __int128 tmp = a;
tmp *= b;
u128 result;
std::memcpy(&result, &tmp, sizeof(u128));
#endif
return result;
}
std::pair<u64, u64> udiv128(u128 dividend, u64 divisor);
std::pair<u64, u64> Divide128On64(u128 dividend, u64 divisor);
} // namespace Common

View file

@ -120,7 +120,7 @@ public:
return std::max(parent.core_timing.GetDowncount(), 0);
}
u64 GetCNTPCT() override {
return CpuCyclesToClockCycles(parent.core_timing.GetTicks());
return Timing::CpuCyclesToClockCycles(parent.core_timing.GetTicks());
}
ARM_Dynarmic& parent;

View file

@ -7,6 +7,7 @@
#include <cinttypes>
#include <limits>
#include "common/logging/log.h"
#include "common/uint128.h"
namespace Core::Timing {
@ -61,10 +62,9 @@ s64 nsToCycles(u64 ns) {
}
u64 CpuCyclesToClockCycles(u64 ticks) {
u64 result = ticks;
result *= CNTFREQ;
result /= BASE_CLOCK_RATE;
return static_cast<u64>(result);
u128 temporal = Common::Multiply64Into128(ticks, CNTFREQ);
std::pair<u64, u64> result = Common::Divide128On64(temporal, BASE_CLOCK_RATE);
return result.first;
}
} // namespace Core::Timing

View file

@ -11,7 +11,7 @@ namespace Core::Timing {
// The below clock rate is based on Switch's clockspeed being widely known as 1.020GHz
// The exact value used is of course unverified.
constexpr u64 BASE_CLOCK_RATE = 1019215872; // Switch clock speed is 1020MHz un/docked
constexpr u64 CNTFREQ = 19200000; // Value from fusee.
constexpr u64 CNTFREQ = 19200000; // Value from fusee.
inline s64 msToCycles(int ms) {
// since ms is int there is no way to overflow