// Copyright 2018 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include "common/assert.h"
#include "common/common_types.h"
#include "video_core/engines/shader_bytecode.h"
#include "video_core/shader/shader_ir.h"
namespace VideoCommon::Shader {
using Tegra::Shader::Instruction;
using Tegra::Shader::OpCode;
u32 ShaderIR::DecodeXmad(BasicBlock& bb, const BasicBlock& code, u32 pc) {
const Instruction instr = {program_code[pc]};
const auto opcode = OpCode::Decode(instr);
UNIMPLEMENTED_IF(instr.xmad.sign_a);
UNIMPLEMENTED_IF(instr.xmad.sign_b);
UNIMPLEMENTED_IF_MSG(instr.generates_cc,
"Condition codes generation in XMAD is not implemented");
Node op_a = GetRegister(instr.gpr8);
// TODO(bunnei): Needs to be fixed once op_a or op_b is signed
UNIMPLEMENTED_IF(instr.xmad.sign_a != instr.xmad.sign_b);
const bool is_signed_a = instr.xmad.sign_a == 1;
const bool is_signed_b = instr.xmad.sign_b == 1;
const bool is_signed_c = is_signed_a;
auto [is_merge, op_b, op_c] = [&]() -> std::tuple<bool, Node, Node> {
switch (opcode->get().GetId()) {
case OpCode::Id::XMAD_CR:
return {instr.xmad.merge_56, GetConstBuffer(instr.cbuf34.index, instr.cbuf34.offset),
GetRegister(instr.gpr39)};
case OpCode::Id::XMAD_RR:
return {instr.xmad.merge_37, GetRegister(instr.gpr20), GetRegister(instr.gpr39)};
case OpCode::Id::XMAD_RC:
return {false, GetRegister(instr.gpr39),
GetConstBuffer(instr.cbuf34.index, instr.cbuf34.offset)};
case OpCode::Id::XMAD_IMM:
return {instr.xmad.merge_37, Immediate(static_cast<u32>(instr.xmad.imm20_16)),
GetRegister(instr.gpr39)};
}
UNIMPLEMENTED_MSG("Unhandled XMAD instruction: {}", opcode->get().GetName());
return {false, Immediate(0), Immediate(0)};
}();
op_a = BitfieldExtract(op_a, instr.xmad.high_a ? 16 : 0, 16);
const Node original_b = op_b;
op_b = BitfieldExtract(op_b, instr.xmad.high_b ? 16 : 0, 16);
// TODO(Rodrigo): Use an appropiate sign for this operation
Node product = Operation(OperationCode::IMul, NO_PRECISE, op_a, op_b);
if (instr.xmad.product_shift_left) {
product = Operation(OperationCode::ILogicalShiftLeft, NO_PRECISE, op_a, Immediate(16));
}
op_c = [&]() {
switch (instr.xmad.mode) {
case Tegra::Shader::XmadMode::None:
return op_c;
case Tegra::Shader::XmadMode::CLo:
return BitfieldExtract(op_c, 0, 16);
case Tegra::Shader::XmadMode::CHi:
return BitfieldExtract(op_c, 16, 16);
case Tegra::Shader::XmadMode::CBcc: {
const Node shifted_b = SignedOperation(OperationCode::ILogicalShiftLeft, is_signed_b,
NO_PRECISE, original_b, Immediate(16));
return SignedOperation(OperationCode::IAdd, is_signed_c, NO_PRECISE, op_c, shifted_b);
}
default:
UNIMPLEMENTED_MSG("Unhandled XMAD mode: {}", static_cast<u32>(instr.xmad.mode.Value()));
return Immediate(0);
}
}();
// TODO(Rodrigo): Use an appropiate sign for this operation
Node sum = Operation(OperationCode::IAdd, product, op_c);
if (is_merge) {
const Node a = BitfieldExtract(sum, 0, 16);
const Node b =
Operation(OperationCode::ILogicalShiftLeft, NO_PRECISE, original_b, Immediate(16));
sum = Operation(OperationCode::IBitwiseOr, NO_PRECISE, a, b);
}
SetInternalFlagsFromInteger(bb, sum, instr.generates_cc);
SetRegister(bb, instr.gpr0, sum);
return pc;
}
} // namespace VideoCommon::Shader