dynarmic/src/frontend/A64/translate/impl/simd_shift_by_immediate.cpp

318 lines
12 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/bit_util.h"
#include "frontend/A64/translate/impl/impl.h"
namespace Dynarmic::A64 {
namespace {
enum class Rounding {
None,
Round
};
enum class Accumulating {
None,
Accumulate
};
enum class Signedness {
Signed,
Unsigned
};
enum class Narrowing {
Truncation,
SaturateToUnsigned,
SaturateToSigned,
};
IR::U128 PerformRoundingCorrection(TranslatorVisitor& v, size_t esize, u64 round_value, IR::U128 original, IR::U128 shifted) {
const IR::U128 round_const = v.ir.VectorBroadcast(esize, v.I(esize, round_value));
const IR::U128 round_correction = v.ir.VectorEqual(esize, v.ir.VectorAnd(original, round_const), round_const);
return v.ir.VectorSub(esize, shifted, round_correction);
}
bool ShiftRight(TranslatorVisitor& v, bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd,
Rounding rounding, Accumulating accumulating, Signedness signedness) {
if (immh == 0b0000) {
return v.DecodeError();
}
if (immh.Bit<3>() && !Q) {
return v.ReservedValue();
}
const size_t esize = 8 << Common::HighestSetBit(immh.ZeroExtend());
const size_t datasize = Q ? 128 : 64;
const u8 shift_amount = static_cast<u8>(2 * esize) - concatenate(immh, immb).ZeroExtend<u8>();
const IR::U128 operand = v.V(datasize, Vn);
IR::U128 result = [&] {
if (signedness == Signedness::Signed) {
return v.ir.VectorArithmeticShiftRight(esize, operand, shift_amount);
}
return v.ir.VectorLogicalShiftRight(esize, operand, shift_amount);
}();
if (rounding == Rounding::Round) {
const u64 round_value = 1ULL << (shift_amount - 1);
result = PerformRoundingCorrection(v, esize, round_value, operand, result);
}
if (accumulating == Accumulating::Accumulate) {
const IR::U128 accumulator = v.V(datasize, Vd);
result = v.ir.VectorAdd(esize, result, accumulator);
}
v.V(datasize, Vd, result);
return true;
}
bool ShiftRightNarrowing(TranslatorVisitor& v, bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd,
Rounding rounding, Narrowing narrowing, Signedness signedness) {
if (immh == 0b0000) {
return v.DecodeError();
}
if (immh.Bit<3>()) {
return v.ReservedValue();
}
const size_t esize = 8 << Common::HighestSetBit(immh.ZeroExtend());
const size_t source_esize = 2 * esize;
const size_t part = Q ? 1 : 0;
const u8 shift_amount = static_cast<u8>(source_esize - concatenate(immh, immb).ZeroExtend());
const IR::U128 operand = v.V(128, Vn);
IR::U128 wide_result = [&] {
if (signedness == Signedness::Signed) {
return v.ir.VectorArithmeticShiftRight(source_esize, operand, shift_amount);
}
return v.ir.VectorLogicalShiftRight(source_esize, operand, shift_amount);
}();
if (rounding == Rounding::Round) {
const u64 round_value = 1ULL << (shift_amount - 1);
wide_result = PerformRoundingCorrection(v, source_esize, round_value, operand, wide_result);
}
const IR::U128 result = [&] {
switch (narrowing) {
case Narrowing::Truncation:
return v.ir.VectorNarrow(source_esize, wide_result);
case Narrowing::SaturateToUnsigned:
if (signedness == Signedness::Signed) {
return v.ir.VectorSignedSaturatedNarrowToUnsigned(source_esize, wide_result);
}
return v.ir.VectorUnsignedSaturatedNarrow(source_esize, wide_result);
case Narrowing::SaturateToSigned:
ASSERT(signedness == Signedness::Signed);
return v.ir.VectorSignedSaturatedNarrowToSigned(source_esize, wide_result);
}
UNREACHABLE();
return IR::U128{};
}();
v.Vpart(64, Vd, part, result);
return true;
}
bool ShiftLeftLong(TranslatorVisitor& v, bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd,
Signedness signedness) {
if (immh == 0b0000) {
return v.DecodeError();
}
if (immh.Bit<3>()) {
return v.ReservedValue();
}
const size_t esize = 8 << Common::HighestSetBit(immh.ZeroExtend());
const size_t datasize = 64;
const size_t part = Q ? 1 : 0;
const u8 shift_amount = concatenate(immh, immb).ZeroExtend<u8>() - static_cast<u8>(esize);
const IR::U128 operand = v.Vpart(datasize, Vn, part);
const IR::U128 expanded_operand = [&] {
if (signedness == Signedness::Signed) {
return v.ir.VectorSignExtend(esize, operand);
}
return v.ir.VectorZeroExtend(esize, operand);
}();
const IR::U128 result = v.ir.VectorLogicalShiftLeft(2 * esize, expanded_operand, shift_amount);
v.V(2 * datasize, Vd, result);
return true;
}
} // Anonymous namespace
bool TranslatorVisitor::SSHR_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRight(*this, Q, immh, immb, Vn, Vd, Rounding::None, Accumulating::None, Signedness::Signed);
}
bool TranslatorVisitor::SRSHR_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRight(*this, Q, immh, immb, Vn, Vd, Rounding::Round, Accumulating::None, Signedness::Signed);
}
bool TranslatorVisitor::SRSRA_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRight(*this, Q, immh, immb, Vn, Vd, Rounding::Round, Accumulating::Accumulate, Signedness::Signed);
}
bool TranslatorVisitor::SSRA_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRight(*this, Q, immh, immb, Vn, Vd, Rounding::None, Accumulating::Accumulate, Signedness::Signed);
}
bool TranslatorVisitor::SHL_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
if (immh == 0b0000) {
return DecodeError();
}
if (immh.Bit<3>() && !Q) {
return ReservedValue();
}
const size_t esize = 8 << Common::HighestSetBit(immh.ZeroExtend());
const size_t datasize = Q ? 128 : 64;
const u8 shift_amount = concatenate(immh, immb).ZeroExtend<u8>() - static_cast<u8>(esize);
const IR::U128 operand = V(datasize, Vn);
const IR::U128 result = ir.VectorLogicalShiftLeft(esize, operand, shift_amount);
V(datasize, Vd, result);
return true;
}
bool TranslatorVisitor::SHRN(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRightNarrowing(*this, Q, immh, immb, Vn, Vd, Rounding::None, Narrowing::Truncation, Signedness::Unsigned);
}
bool TranslatorVisitor::RSHRN(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRightNarrowing(*this, Q, immh, immb, Vn, Vd, Rounding::Round, Narrowing::Truncation, Signedness::Unsigned);
}
bool TranslatorVisitor::SQSHL_imm_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
if (!Q && immh.Bit<3>()) {
return ReservedValue();
}
const size_t esize = 8 << Common::HighestSetBit(immh.ZeroExtend());
const size_t datasize = Q ? 128 : 64;
const size_t shift = concatenate(immh, immb).ZeroExtend() - esize;
const IR::U128 operand = V(datasize, Vn);
const IR::U128 shift_vec = ir.VectorBroadcast(esize, I(esize, shift));
const IR::U128 result = ir.VectorSignedSaturatedShiftLeft(esize, operand, shift_vec);
V(datasize, Vd, result);
return true;
}
bool TranslatorVisitor::SQSHRN_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRightNarrowing(*this, Q, immh, immb, Vn, Vd, Rounding::None, Narrowing::SaturateToSigned, Signedness::Signed);
}
bool TranslatorVisitor::SQRSHRN_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRightNarrowing(*this, Q, immh, immb, Vn, Vd, Rounding::Round, Narrowing::SaturateToSigned, Signedness::Signed);
}
bool TranslatorVisitor::SQSHRUN_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRightNarrowing(*this, Q, immh, immb, Vn, Vd, Rounding::None, Narrowing::SaturateToUnsigned, Signedness::Signed);
}
bool TranslatorVisitor::SQRSHRUN_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRightNarrowing(*this, Q, immh, immb, Vn, Vd, Rounding::Round, Narrowing::SaturateToUnsigned, Signedness::Signed);
}
bool TranslatorVisitor::UQSHRN_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRightNarrowing(*this, Q, immh, immb, Vn, Vd, Rounding::None, Narrowing::SaturateToUnsigned, Signedness::Unsigned);
}
bool TranslatorVisitor::UQRSHRN_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRightNarrowing(*this, Q, immh, immb, Vn, Vd, Rounding::Round, Narrowing::SaturateToUnsigned, Signedness::Unsigned);
}
bool TranslatorVisitor::SSHLL(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftLeftLong(*this, Q, immh, immb, Vn, Vd, Signedness::Signed);
}
bool TranslatorVisitor::URSHR_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRight(*this, Q, immh, immb, Vn, Vd, Rounding::Round, Accumulating::None, Signedness::Unsigned);
}
bool TranslatorVisitor::URSRA_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRight(*this, Q, immh, immb, Vn, Vd, Rounding::Round, Accumulating::Accumulate, Signedness::Unsigned);
}
bool TranslatorVisitor::USHR_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRight(*this, Q, immh, immb, Vn, Vd, Rounding::None, Accumulating::None, Signedness::Unsigned);
}
bool TranslatorVisitor::USRA_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftRight(*this, Q, immh, immb, Vn, Vd, Rounding::None, Accumulating::Accumulate, Signedness::Unsigned);
}
bool TranslatorVisitor::USHLL(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
return ShiftLeftLong(*this, Q, immh, immb, Vn, Vd, Signedness::Unsigned);
}
bool TranslatorVisitor::SRI_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
if (immh == 0b0000) {
return DecodeError();
}
if (!Q && immh.Bit<3>()) {
return ReservedValue();
}
const size_t esize = 8 << Common::HighestSetBit(immh.ZeroExtend());
const size_t datasize = Q ? 128 : 64;
const u8 shift_amount = static_cast<u8>((esize * 2) - concatenate(immh, immb).ZeroExtend<u8>());
const u64 mask = shift_amount == esize ? 0 : Common::Ones<u64>(esize) >> shift_amount;
const IR::U128 operand1 = V(datasize, Vn);
const IR::U128 operand2 = V(datasize, Vd);
const IR::U128 shifted = ir.VectorLogicalShiftRight(esize, operand1, shift_amount);
const IR::U128 mask_vec = ir.VectorBroadcast(esize, I(esize, mask));
const IR::U128 result = ir.VectorOr(ir.VectorAnd(operand2, ir.VectorNot(mask_vec)), shifted);
V(datasize, Vd, result);
return true;
}
bool TranslatorVisitor::SLI_2(bool Q, Imm<4> immh, Imm<3> immb, Vec Vn, Vec Vd) {
if (immh == 0b0000) {
return DecodeError();
}
if (!Q && immh.Bit<3>()) {
return ReservedValue();
}
const size_t esize = 8 << Common::HighestSetBit(immh.ZeroExtend());
const size_t datasize = Q ? 128 : 64;
const u8 shift_amount = concatenate(immh, immb).ZeroExtend<u8>() - static_cast<u8>(esize);
const u64 mask = Common::Ones<u64>(esize) << shift_amount;
const IR::U128 operand1 = V(datasize, Vn);
const IR::U128 operand2 = V(datasize, Vd);
const IR::U128 shifted = ir.VectorLogicalShiftLeft(esize, operand1, shift_amount);
const IR::U128 mask_vec = ir.VectorBroadcast(esize, I(esize, mask));
const IR::U128 result = ir.VectorOr(ir.VectorAnd(operand2, ir.VectorNot(mask_vec)), shifted);
V(datasize, Vd, result);
return true;
}
} // namespace Dynarmic::A64