// Copyright 2021 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include "common/bit_field.h"
#include "common/common_types.h"
#include "shader_recompiler/frontend/maxwell/translate/impl/common_encoding.h"
#include "shader_recompiler/frontend/maxwell/translate/impl/impl.h"
namespace Shader::Maxwell {
namespace {
enum class FloatFormat : u64 {
F16 = 1,
F32 = 2,
F64 = 3,
};
enum class IntFormat : u64 {
U8 = 0,
U16 = 1,
U32 = 2,
U64 = 3,
};
union Encoding {
u64 raw;
BitField<0, 8, IR::Reg> dest_reg;
BitField<8, 2, FloatFormat> float_format;
BitField<10, 2, IntFormat> int_format;
BitField<13, 1, u64> is_signed;
BitField<39, 2, FpRounding> fp_rounding;
BitField<41, 2, u64> selector;
BitField<47, 1, u64> cc;
BitField<45, 1, u64> neg;
BitField<49, 1, u64> abs;
};
bool Is64(u64 insn) {
return Encoding{insn}.int_format == IntFormat::U64;
}
int BitSize(FloatFormat format) {
switch (format) {
case FloatFormat::F16:
return 16;
case FloatFormat::F32:
return 32;
case FloatFormat::F64:
return 64;
}
throw NotImplementedException("Invalid float format {}", format);
}
IR::U32 SmallAbs(TranslatorVisitor& v, const IR::U32& value, int bitsize) {
const IR::U32 least_value{v.ir.Imm32(-(1 << (bitsize - 1)))};
const IR::U32 mask{v.ir.ShiftRightArithmetic(value, v.ir.Imm32(bitsize - 1))};
const IR::U32 absolute{v.ir.BitwiseXor(v.ir.IAdd(value, mask), mask)};
const IR::U1 is_least{v.ir.IEqual(value, least_value)};
return IR::U32{v.ir.Select(is_least, value, absolute)};
}
void I2F(TranslatorVisitor& v, u64 insn, IR::U32U64 src) {
const Encoding i2f{insn};
if (i2f.cc != 0) {
throw NotImplementedException("CC");
}
const bool is_signed{i2f.is_signed != 0};
int src_bitsize{};
switch (i2f.int_format) {
case IntFormat::U8:
src = v.ir.BitFieldExtract(src, v.ir.Imm32(static_cast<u32>(i2f.selector) * 8),
v.ir.Imm32(8), is_signed);
if (i2f.abs != 0) {
src = SmallAbs(v, src, 8);
}
src_bitsize = 8;
break;
case IntFormat::U16:
if (i2f.selector == 1 || i2f.selector == 3) {
throw NotImplementedException("Invalid U16 selector {}", i2f.selector.Value());
}
src = v.ir.BitFieldExtract(src, v.ir.Imm32(static_cast<u32>(i2f.selector) * 8),
v.ir.Imm32(16), is_signed);
if (i2f.abs != 0) {
src = SmallAbs(v, src, 16);
}
src_bitsize = 16;
break;
case IntFormat::U32:
case IntFormat::U64:
if (i2f.selector != 0) {
throw NotImplementedException("Unexpected selector {}", i2f.selector.Value());
}
if (i2f.abs != 0 && is_signed) {
src = v.ir.IAbs(src);
}
src_bitsize = i2f.int_format == IntFormat::U64 ? 64 : 32;
break;
}
const int conversion_src_bitsize{i2f.int_format == IntFormat::U64 ? 64 : 32};
const int dst_bitsize{BitSize(i2f.float_format)};
IR::F16F32F64 value{v.ir.ConvertIToF(dst_bitsize, conversion_src_bitsize, is_signed, src)};
if (i2f.neg != 0) {
if (i2f.abs != 0 || !is_signed) {
// We know the value is positive
value = v.ir.FPNeg(value);
} else {
// Only negate if the input isn't the lowest value
IR::U1 is_least;
if (src_bitsize == 64) {
is_least = v.ir.IEqual(src, v.ir.Imm64(std::numeric_limits<s64>::min()));
} else {
const IR::U32 least_value{v.ir.Imm32(-(1 << (src_bitsize - 1)))};
is_least = v.ir.IEqual(src, least_value);
}
value = IR::F16F32F64{v.ir.Select(is_least, value, v.ir.FPNeg(value))};
}
}
switch (i2f.float_format) {
case FloatFormat::F16: {
const IR::F16 zero{v.ir.FPConvert(16, v.ir.Imm32(0.0f))};
v.X(i2f.dest_reg, v.ir.PackFloat2x16(v.ir.CompositeConstruct(value, zero)));
break;
}
case FloatFormat::F32:
v.F(i2f.dest_reg, value);
break;
case FloatFormat::F64: {
if (!IR::IsAligned(i2f.dest_reg, 2)) {
throw NotImplementedException("Unaligned destination {}", i2f.dest_reg.Value());
}
const IR::Value vector{v.ir.UnpackDouble2x32(value)};
for (int i = 0; i < 2; ++i) {
v.X(i2f.dest_reg + i, IR::U32{v.ir.CompositeExtract(vector, static_cast<size_t>(i))});
}
break;
}
default:
throw NotImplementedException("Invalid float format {}", i2f.float_format.Value());
}
}
} // Anonymous namespace
void TranslatorVisitor::I2F_reg(u64 insn) {
if (Is64(insn)) {
union {
u64 raw;
BitField<20, 8, IR::Reg> reg;
} const value{insn};
const IR::Value regs{ir.CompositeConstruct(ir.GetReg(value.reg), ir.GetReg(value.reg + 1))};
I2F(*this, insn, ir.PackUint2x32(regs));
} else {
I2F(*this, insn, GetReg20(insn));
}
}
void TranslatorVisitor::I2F_cbuf(u64 insn) {
if (Is64(insn)) {
I2F(*this, insn, GetPackedCbuf(insn));
} else {
I2F(*this, insn, GetCbuf(insn));
}
}
void TranslatorVisitor::I2F_imm(u64 insn) {
if (Is64(insn)) {
I2F(*this, insn, GetPackedImm20(insn));
} else {
I2F(*this, insn, GetImm20(insn));
}
}
} // namespace Shader::Maxwell