// 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::ConditionCode;
using Tegra::Shader::Instruction;
using Tegra::Shader::OpCode;
using Tegra::Shader::Register;
u32 ShaderIR::DecodeOther(NodeBlock& bb, u32 pc) {
const Instruction instr = {program_code[pc]};
const auto opcode = OpCode::Decode(instr);
switch (opcode->get().GetId()) {
case OpCode::Id::EXIT: {
const Tegra::Shader::ConditionCode cc = instr.flow_condition_code;
UNIMPLEMENTED_IF_MSG(cc != Tegra::Shader::ConditionCode::T, "EXIT condition code used: {}",
static_cast<u32>(cc));
switch (instr.flow.cond) {
case Tegra::Shader::FlowCondition::Always:
bb.push_back(Operation(OperationCode::Exit));
if (instr.pred.pred_index == static_cast<u64>(Tegra::Shader::Pred::UnusedIndex)) {
// If this is an unconditional exit then just end processing here,
// otherwise we have to account for the possibility of the condition
// not being met, so continue processing the next instruction.
pc = MAX_PROGRAM_LENGTH - 1;
}
break;
case Tegra::Shader::FlowCondition::Fcsm_Tr:
// TODO(bunnei): What is this used for? If we assume this conditon is not
// satisifed, dual vertex shaders in Farming Simulator make more sense
UNIMPLEMENTED_MSG("Skipping unknown FlowCondition::Fcsm_Tr");
break;
default:
UNIMPLEMENTED_MSG("Unhandled flow condition: {}",
static_cast<u32>(instr.flow.cond.Value()));
}
break;
}
case OpCode::Id::KIL: {
UNIMPLEMENTED_IF(instr.flow.cond != Tegra::Shader::FlowCondition::Always);
const Tegra::Shader::ConditionCode cc = instr.flow_condition_code;
UNIMPLEMENTED_IF_MSG(cc != Tegra::Shader::ConditionCode::T, "KIL condition code used: {}",
static_cast<u32>(cc));
bb.push_back(Operation(OperationCode::Discard));
break;
}
case OpCode::Id::MOV_SYS: {
switch (instr.sys20) {
case Tegra::Shader::SystemVariable::InvocationInfo: {
LOG_WARNING(HW_GPU, "MOV_SYS instruction with InvocationInfo is incomplete");
SetRegister(bb, instr.gpr0, Immediate(0u));
break;
}
case Tegra::Shader::SystemVariable::Ydirection: {
// Config pack's third value is Y_NEGATE's state.
SetRegister(bb, instr.gpr0, Operation(OperationCode::YNegate));
break;
}
default:
UNIMPLEMENTED_MSG("Unhandled system move: {}", static_cast<u32>(instr.sys20.Value()));
}
break;
}
case OpCode::Id::BRA: {
UNIMPLEMENTED_IF_MSG(instr.bra.constant_buffer != 0,
"BRA with constant buffers are not implemented");
const u32 target = pc + instr.bra.GetBranchTarget();
const Node branch = Operation(OperationCode::Branch, Immediate(target));
const Tegra::Shader::ConditionCode cc = instr.flow_condition_code;
if (cc != Tegra::Shader::ConditionCode::T) {
bb.push_back(Conditional(GetConditionCode(cc), {branch}));
} else {
bb.push_back(branch);
}
break;
}
case OpCode::Id::SSY: {
UNIMPLEMENTED_IF_MSG(instr.bra.constant_buffer != 0,
"Constant buffer flow is not supported");
// The SSY opcode tells the GPU where to re-converge divergent execution paths, it sets the
// target of the jump that the SYNC instruction will make. The SSY opcode has a similar
// structure to the BRA opcode.
const u32 target = pc + instr.bra.GetBranchTarget();
bb.push_back(Operation(OperationCode::PushFlowStack, Immediate(target)));
break;
}
case OpCode::Id::PBK: {
UNIMPLEMENTED_IF_MSG(instr.bra.constant_buffer != 0,
"Constant buffer PBK is not supported");
// PBK pushes to a stack the address where BRK will jump to. This shares stack with SSY but
// using SYNC on a PBK address will kill the shader execution. We don't emulate this because
// it's very unlikely a driver will emit such invalid shader.
const u32 target = pc + instr.bra.GetBranchTarget();
bb.push_back(Operation(OperationCode::PushFlowStack, Immediate(target)));
break;
}
case OpCode::Id::SYNC: {
const Tegra::Shader::ConditionCode cc = instr.flow_condition_code;
UNIMPLEMENTED_IF_MSG(cc != Tegra::Shader::ConditionCode::T, "SYNC condition code used: {}",
static_cast<u32>(cc));
// The SYNC opcode jumps to the address previously set by the SSY opcode
bb.push_back(Operation(OperationCode::PopFlowStack));
break;
}
case OpCode::Id::BRK: {
const Tegra::Shader::ConditionCode cc = instr.flow_condition_code;
UNIMPLEMENTED_IF_MSG(cc != Tegra::Shader::ConditionCode::T, "BRK condition code used: {}",
static_cast<u32>(cc));
// The BRK opcode jumps to the address previously set by the PBK opcode
bb.push_back(Operation(OperationCode::PopFlowStack));
break;
}
case OpCode::Id::IPA: {
const auto& attribute = instr.attribute.fmt28;
const Tegra::Shader::IpaMode input_mode{instr.ipa.interp_mode.Value(),
instr.ipa.sample_mode.Value()};
const Node attr = GetInputAttribute(attribute.index, attribute.element, input_mode);
Node value = attr;
const Tegra::Shader::Attribute::Index index = attribute.index.Value();
if (index >= Tegra::Shader::Attribute::Index::Attribute_0 &&
index <= Tegra::Shader::Attribute::Index::Attribute_31) {
// TODO(Blinkhawk): There are cases where a perspective attribute use PASS.
// In theory by setting them as perspective, OpenGL does the perspective correction.
// A way must figured to reverse the last step of it.
if (input_mode.interpolation_mode == Tegra::Shader::IpaInterpMode::Multiply) {
value = Operation(OperationCode::FMul, PRECISE, value, GetRegister(instr.gpr20));
}
}
value = GetSaturatedFloat(value, instr.ipa.saturate);
SetRegister(bb, instr.gpr0, value);
break;
}
case OpCode::Id::OUT_R: {
UNIMPLEMENTED_IF_MSG(instr.gpr20.Value() != Register::ZeroIndex,
"Stream buffer is not supported");
if (instr.out.emit) {
// gpr0 is used to store the next address and gpr8 contains the address to emit.
// Hardware uses pointers here but we just ignore it
bb.push_back(Operation(OperationCode::EmitVertex));
SetRegister(bb, instr.gpr0, Immediate(0));
}
if (instr.out.cut) {
bb.push_back(Operation(OperationCode::EndPrimitive));
}
break;
}
case OpCode::Id::ISBERD: {
UNIMPLEMENTED_IF(instr.isberd.o != 0);
UNIMPLEMENTED_IF(instr.isberd.skew != 0);
UNIMPLEMENTED_IF(instr.isberd.shift != Tegra::Shader::IsberdShift::None);
UNIMPLEMENTED_IF(instr.isberd.mode != Tegra::Shader::IsberdMode::None);
LOG_WARNING(HW_GPU, "ISBERD instruction is incomplete");
SetRegister(bb, instr.gpr0, GetRegister(instr.gpr8));
break;
}
case OpCode::Id::DEPBAR: {
LOG_WARNING(HW_GPU, "DEPBAR instruction is stubbed");
break;
}
default:
UNIMPLEMENTED_MSG("Unhandled instruction: {}", opcode->get().GetName());
}
return pc;
}
} // namespace VideoCommon::Shader
