mirror of
https://github.com/azahar-emu/dynarmic
synced 2025-11-11 09:30:00 +01:00
c9777ef997
While initially done to potentially prevent creating bugs due to C++ having a silly type-promotion mechanism involving types < sizeof(int) and unsignedness, given that the bulk of these functions' usages are on exit paths, these can return the correct type to avoid the need to cast at every usage point.
58 lines
1.8 KiB
C++
58 lines
1.8 KiB
C++
/* This file is part of the dynarmic project.
|
|
* Copyright (c) 2018 MerryMage
|
|
* This software may be used and distributed according to the terms of the GNU
|
|
* General Public License version 2 or any later version.
|
|
*/
|
|
|
|
#include "common/fp/fpcr.h"
|
|
#include "common/fp/fpsr.h"
|
|
#include "common/fp/fused.h"
|
|
#include "common/fp/info.h"
|
|
#include "common/fp/op/FPNeg.h"
|
|
#include "common/fp/op/FPRSqrtStepFused.h"
|
|
#include "common/fp/process_nan.h"
|
|
#include "common/fp/unpacked.h"
|
|
|
|
namespace Dynarmic::FP {
|
|
|
|
template<typename FPT>
|
|
FPT FPRSqrtStepFused(FPT op1, FPT op2, FPCR fpcr, FPSR& fpsr) {
|
|
op1 = FPNeg(op1);
|
|
|
|
const auto [type1, sign1, value1] = FPUnpack(op1, fpcr, fpsr);
|
|
const auto [type2, sign2, value2] = FPUnpack(op2, fpcr, fpsr);
|
|
|
|
if (const auto maybe_nan = FPProcessNaNs(type1, type2, op1, op2, fpcr, fpsr)) {
|
|
return *maybe_nan;
|
|
}
|
|
|
|
const bool inf1 = type1 == FPType::Infinity;
|
|
const bool inf2 = type2 == FPType::Infinity;
|
|
const bool zero1 = type1 == FPType::Zero;
|
|
const bool zero2 = type2 == FPType::Zero;
|
|
|
|
if ((inf1 && zero2) || (zero1 && inf2)) {
|
|
// return +1.5
|
|
return FPValue<FPT, false, -1, 3>();
|
|
}
|
|
|
|
if (inf1 || inf2) {
|
|
return FPInfo<FPT>::Infinity(sign1 != sign2);
|
|
}
|
|
|
|
// result_value = (3.0 + (value1 * value2)) / 2.0
|
|
FPUnpacked result_value = FusedMulAdd(ToNormalized(false, 0, 3), value1, value2);
|
|
result_value.exponent--;
|
|
|
|
if (result_value.mantissa == 0) {
|
|
return FPInfo<FPT>::Zero(fpcr.RMode() == RoundingMode::TowardsMinusInfinity);
|
|
}
|
|
return FPRound<FPT>(result_value, fpcr, fpsr);
|
|
}
|
|
|
|
template u16 FPRSqrtStepFused<u16>(u16 op1, u16 op2, FPCR fpcr, FPSR& fpsr);
|
|
template u32 FPRSqrtStepFused<u32>(u32 op1, u32 op2, FPCR fpcr, FPSR& fpsr);
|
|
template u64 FPRSqrtStepFused<u64>(u64 op1, u64 op2, FPCR fpcr, FPSR& fpsr);
|
|
|
|
} // namespace Dynarmic::FP
|