// Copyright 2018 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <map>
#include <set>
#include <string>
#include <string_view>
#include "common/assert.h"
#include "common/common_types.h"
#include "video_core/engines/shader_bytecode.h"
#include "video_core/renderer_opengl/gl_rasterizer.h"
#include "video_core/renderer_opengl/gl_shader_decompiler.h"
namespace GLShader::Decompiler {
using Tegra::Shader::Attribute;
using Tegra::Shader::Instruction;
using Tegra::Shader::LogicOperation;
using Tegra::Shader::OpCode;
using Tegra::Shader::Register;
using Tegra::Shader::Sampler;
using Tegra::Shader::SubOp;
constexpr u32 PROGRAM_END = MAX_PROGRAM_CODE_LENGTH;
class DecompileFail : public std::runtime_error {
public:
using std::runtime_error::runtime_error;
};
/// Describes the behaviour of code path of a given entry point and a return point.
enum class ExitMethod {
Undetermined, ///< Internal value. Only occur when analyzing JMP loop.
AlwaysReturn, ///< All code paths reach the return point.
Conditional, ///< Code path reaches the return point or an END instruction conditionally.
AlwaysEnd, ///< All code paths reach a END instruction.
};
/// A subroutine is a range of code refereced by a CALL, IF or LOOP instruction.
struct Subroutine {
/// Generates a name suitable for GLSL source code.
std::string GetName() const {
return "sub_" + std::to_string(begin) + '_' + std::to_string(end) + '_' + suffix;
}
u32 begin; ///< Entry point of the subroutine.
u32 end; ///< Return point of the subroutine.
const std::string& suffix; ///< Suffix of the shader, used to make a unique subroutine name
ExitMethod exit_method; ///< Exit method of the subroutine.
std::set<u32> labels; ///< Addresses refereced by JMP instructions.
bool operator<(const Subroutine& rhs) const {
return std::tie(begin, end) < std::tie(rhs.begin, rhs.end);
}
};
/// Analyzes shader code and produces a set of subroutines.
class ControlFlowAnalyzer {
public:
ControlFlowAnalyzer(const ProgramCode& program_code, u32 main_offset, const std::string& suffix)
: program_code(program_code) {
// Recursively finds all subroutines.
const Subroutine& program_main = AddSubroutine(main_offset, PROGRAM_END, suffix);
if (program_main.exit_method != ExitMethod::AlwaysEnd)
throw DecompileFail("Program does not always end");
}
std::set<Subroutine> GetSubroutines() {
return std::move(subroutines);
}
private:
const ProgramCode& program_code;
std::set<Subroutine> subroutines;
std::map<std::pair<u32, u32>, ExitMethod> exit_method_map;
/// Adds and analyzes a new subroutine if it is not added yet.
const Subroutine& AddSubroutine(u32 begin, u32 end, const std::string& suffix) {
Subroutine subroutine{begin, end, suffix, ExitMethod::Undetermined, {}};
const auto iter = subroutines.find(subroutine);
if (iter != subroutines.end()) {
return *iter;
}
subroutine.exit_method = Scan(begin, end, subroutine.labels);
if (subroutine.exit_method == ExitMethod::Undetermined) {
throw DecompileFail("Recursive function detected");
}
return *subroutines.insert(std::move(subroutine)).first;
}
/// Merges exit method of two parallel branches.
static ExitMethod ParallelExit(ExitMethod a, ExitMethod b) {
if (a == ExitMethod::Undetermined) {
return b;
}
if (b == ExitMethod::Undetermined) {
return a;
}
if (a == b) {
return a;
}
return ExitMethod::Conditional;
}
/// Scans a range of code for labels and determines the exit method.
ExitMethod Scan(u32 begin, u32 end, std::set<u32>& labels) {
auto [iter, inserted] =
exit_method_map.emplace(std::make_pair(begin, end), ExitMethod::Undetermined);
ExitMethod& exit_method = iter->second;
if (!inserted)
return exit_method;
for (u32 offset = begin; offset != end && offset != PROGRAM_END; ++offset) {
const Instruction instr = {program_code[offset]};
if (const auto opcode = OpCode::Decode(instr)) {
switch (opcode->GetId()) {
case OpCode::Id::EXIT: {
// The EXIT instruction can be predicated, which means that the shader can
// conditionally end on this instruction. We have to consider the case where the
// condition is not met and check the exit method of that other basic block.
using Tegra::Shader::Pred;
if (instr.pred.pred_index == static_cast<u64>(Pred::UnusedIndex)) {
return exit_method = ExitMethod::AlwaysEnd;
} else {
ExitMethod not_met = Scan(offset + 1, end, labels);
return exit_method = ParallelExit(ExitMethod::AlwaysEnd, not_met);
}
}
case OpCode::Id::BRA: {
u32 target = offset + instr.bra.GetBranchTarget();
labels.insert(target);
ExitMethod no_jmp = Scan(offset + 1, end, labels);
ExitMethod jmp = Scan(target, end, labels);
return exit_method = ParallelExit(no_jmp, jmp);
}
}
}
}
return exit_method = ExitMethod::AlwaysReturn;
}
};
class ShaderWriter {
public:
void AddLine(std::string_view text) {
DEBUG_ASSERT(scope >= 0);
if (!text.empty()) {
AppendIndentation();
}
shader_source += text;
AddNewLine();
}
void AddLine(char character) {
DEBUG_ASSERT(scope >= 0);
AppendIndentation();
shader_source += character;
AddNewLine();
}
void AddNewLine() {
DEBUG_ASSERT(scope >= 0);
shader_source += '\n';
}
std::string GetResult() {
return std::move(shader_source);
}
int scope = 0;
private:
void AppendIndentation() {
shader_source.append(static_cast<size_t>(scope) * 4, ' ');
}
std::string shader_source;
};
/**
* Represents an emulated shader register, used to track the state of that register for emulation
* with GLSL. At this time, a register can be used as a float or an integer. This class is used for
* bookkeeping within the GLSL program.
*/
class GLSLRegister {
public:
enum class Type {
Float,
Integer,
UnsignedInteger,
};
GLSLRegister(size_t index, const std::string& suffix) : index{index}, suffix{suffix} {}
/// Gets the GLSL type string for a register
static std::string GetTypeString() {
return "float";
}
/// Gets the GLSL register prefix string, used for declarations and referencing
static std::string GetPrefixString() {
return "reg_";
}
/// Returns a GLSL string representing the current state of the register
std::string GetString() const {
return GetPrefixString() + std::to_string(index) + '_' + suffix;
}
/// Returns the index of the register
size_t GetIndex() const {
return index;
}
private:
const size_t index;
const std::string& suffix;
};
/**
* Used to manage shader registers that are emulated with GLSL. This class keeps track of the state
* of all registers (e.g. whether they are currently being used as Floats or Integers), and
* generates the necessary GLSL code to perform conversions as needed. This class is used for
* bookkeeping within the GLSL program.
*/
class GLSLRegisterManager {
public:
GLSLRegisterManager(ShaderWriter& shader, ShaderWriter& declarations,
const Maxwell3D::Regs::ShaderStage& stage, const std::string& suffix)
: shader{shader}, declarations{declarations}, stage{stage}, suffix{suffix} {
BuildRegisterList();
}
/**
* Returns code that does an integer size conversion for the specified size.
* @param value Value to perform integer size conversion on.
* @param size Register size to use for conversion instructions.
* @returns GLSL string corresponding to the value converted to the specified size.
*/
static std::string ConvertIntegerSize(const std::string& value, Register::Size size) {
switch (size) {
case Register::Size::Byte:
return "((" + value + " << 24) >> 24)";
case Register::Size::Short:
return "((" + value + " << 16) >> 16)";
case Register::Size::Word:
// Default - do nothing
return value;
default:
LOG_CRITICAL(HW_GPU, "Unimplemented conversion size {}", static_cast<u32>(size));
UNREACHABLE();
}
}
/**
* Gets a register as an float.
* @param reg The register to get.
* @param elem The element to use for the operation.
* @returns GLSL string corresponding to the register as a float.
*/
std::string GetRegisterAsFloat(const Register& reg, unsigned elem = 0) {
return GetRegister(reg, elem);
}
/**
* Gets a register as an integer.
* @param reg The register to get.
* @param elem The element to use for the operation.
* @param is_signed Whether to get the register as a signed (or unsigned) integer.
* @param size Register size to use for conversion instructions.
* @returns GLSL string corresponding to the register as an integer.
*/
std::string GetRegisterAsInteger(const Register& reg, unsigned elem = 0, bool is_signed = true,
Register::Size size = Register::Size::Word) {
const std::string func{is_signed ? "floatBitsToInt" : "floatBitsToUint"};
const std::string value{func + '(' + GetRegister(reg, elem) + ')'};
return ConvertIntegerSize(value, size);
}
/**
* Writes code that does a register assignment to float value operation.
* @param reg The destination register to use.
* @param elem The element to use for the operation.
* @param value The code representing the value to assign.
* @param dest_num_components Number of components in the destination.
* @param value_num_components Number of components in the value.
* @param is_saturated Optional, when True, saturates the provided value.
* @param dest_elem Optional, the destination element to use for the operation.
*/
void SetRegisterToFloat(const Register& reg, u64 elem, const std::string& value,
u64 dest_num_components, u64 value_num_components,
bool is_saturated = false, u64 dest_elem = 0) {
SetRegister(reg, elem, is_saturated ? "clamp(" + value + ", 0.0, 1.0)" : value,
dest_num_components, value_num_components, dest_elem);
}
/**
* Writes code that does a register assignment to integer value operation.
* @param reg The destination register to use.
* @param elem The element to use for the operation.
* @param value The code representing the value to assign.
* @param dest_num_components Number of components in the destination.
* @param value_num_components Number of components in the value.
* @param is_saturated Optional, when True, saturates the provided value.
* @param dest_elem Optional, the destination element to use for the operation.
* @param size Register size to use for conversion instructions.
*/
void SetRegisterToInteger(const Register& reg, bool is_signed, u64 elem,
const std::string& value, u64 dest_num_components,
u64 value_num_components, bool is_saturated = false,
u64 dest_elem = 0, Register::Size size = Register::Size::Word) {
ASSERT_MSG(!is_saturated, "Unimplemented");
const std::string func{is_signed ? "intBitsToFloat" : "uintBitsToFloat"};
SetRegister(reg, elem, func + '(' + ConvertIntegerSize(value, size) + ')',
dest_num_components, value_num_components, dest_elem);
}
/**
* Writes code that does a register assignment to input attribute operation. Input attributes
* are stored as floats, so this may require conversion.
* @param reg The destination register to use.
* @param elem The element to use for the operation.
* @param attribute The input attribute to use as the source value.
*/
void SetRegisterToInputAttibute(const Register& reg, u64 elem, Attribute::Index attribute) {
std::string dest = GetRegisterAsFloat(reg);
std::string src = GetInputAttribute(attribute) + GetSwizzle(elem);
shader.AddLine(dest + " = " + src + ';');
}
/**
* Writes code that does a output attribute assignment to register operation. Output attributes
* are stored as floats, so this may require conversion.
* @param attribute The destination output attribute.
* @param elem The element to use for the operation.
* @param reg The register to use as the source value.
*/
void SetOutputAttributeToRegister(Attribute::Index attribute, u64 elem, const Register& reg) {
std::string dest = GetOutputAttribute(attribute) + GetSwizzle(elem);
std::string src = GetRegisterAsFloat(reg);
shader.AddLine(dest + " = " + src + ';');
}
/// Generates code representing a uniform (C buffer) register, interpreted as the input type.
std::string GetUniform(u64 index, u64 offset, GLSLRegister::Type type) {
declr_const_buffers[index].MarkAsUsed(index, offset, stage);
std::string value = 'c' + std::to_string(index) + '[' + std::to_string(offset / 4) + "][" +
std::to_string(offset % 4) + ']';
if (type == GLSLRegister::Type::Float) {
return value;
} else if (type == GLSLRegister::Type::Integer) {
return "floatBitsToInt(" + value + ')';
} else {
UNREACHABLE();
}
}
std::string GetUniformIndirect(u64 index, s64 offset, const Register& index_reg,
GLSLRegister::Type type) {
declr_const_buffers[index].MarkAsUsedIndirect(index, stage);
std::string final_offset = "((floatBitsToInt(" + GetRegister(index_reg, 0) + ") + " +
std::to_string(offset) + ") / 4)";
std::string value =
'c' + std::to_string(index) + '[' + final_offset + " / 4][" + final_offset + " % 4]";
if (type == GLSLRegister::Type::Float) {
return value;
} else if (type == GLSLRegister::Type::Integer) {
return "floatBitsToInt(" + value + ')';
} else {
UNREACHABLE();
}
}
/// Add declarations for registers
void GenerateDeclarations(const std::string& suffix) {
for (const auto& reg : regs) {
declarations.AddLine(GLSLRegister::GetTypeString() + ' ' + reg.GetPrefixString() +
std::to_string(reg.GetIndex()) + '_' + suffix + " = 0;");
}
declarations.AddNewLine();
for (const auto& index : declr_input_attribute) {
// TODO(bunnei): Use proper number of elements for these
declarations.AddLine("layout(location = " +
std::to_string(static_cast<u32>(index) -
static_cast<u32>(Attribute::Index::Attribute_0)) +
") in vec4 " + GetInputAttribute(index) + ';');
}
declarations.AddNewLine();
for (const auto& index : declr_output_attribute) {
// TODO(bunnei): Use proper number of elements for these
declarations.AddLine("layout(location = " +
std::to_string(static_cast<u32>(index) -
static_cast<u32>(Attribute::Index::Attribute_0)) +
") out vec4 " + GetOutputAttribute(index) + ';');
}
declarations.AddNewLine();
unsigned const_buffer_layout = 0;
for (const auto& entry : GetConstBuffersDeclarations()) {
declarations.AddLine("layout(std140) uniform " + entry.GetName());
declarations.AddLine('{');
declarations.AddLine(" vec4 c" + std::to_string(entry.GetIndex()) +
"[MAX_CONSTBUFFER_ELEMENTS];");
declarations.AddLine("};");
declarations.AddNewLine();
++const_buffer_layout;
}
declarations.AddNewLine();
// Append the sampler2D array for the used textures.
size_t num_samplers = GetSamplers().size();
if (num_samplers > 0) {
declarations.AddLine("uniform sampler2D " + SamplerEntry::GetArrayName(stage) + '[' +
std::to_string(num_samplers) + "];");
declarations.AddNewLine();
}
}
/// Returns a list of constant buffer declarations
std::vector<ConstBufferEntry> GetConstBuffersDeclarations() const {
std::vector<ConstBufferEntry> result;
std::copy_if(declr_const_buffers.begin(), declr_const_buffers.end(),
std::back_inserter(result), [](const auto& entry) { return entry.IsUsed(); });
return result;
}
/// Returns a list of samplers used in the shader
std::vector<SamplerEntry> GetSamplers() const {
return used_samplers;
}
/// Returns the GLSL sampler used for the input shader sampler, and creates a new one if
/// necessary.
std::string AccessSampler(const Sampler& sampler) {
size_t offset = static_cast<size_t>(sampler.index.Value());
// If this sampler has already been used, return the existing mapping.
auto itr =
std::find_if(used_samplers.begin(), used_samplers.end(),
[&](const SamplerEntry& entry) { return entry.GetOffset() == offset; });
if (itr != used_samplers.end()) {
return itr->GetName();
}
// Otherwise create a new mapping for this sampler
size_t next_index = used_samplers.size();
SamplerEntry entry{stage, offset, next_index};
used_samplers.emplace_back(entry);
return entry.GetName();
}
private:
/// Generates code representing a temporary (GPR) register.
std::string GetRegister(const Register& reg, unsigned elem) {
if (reg == Register::ZeroIndex) {
return "0";
}
return regs[reg.GetSwizzledIndex(elem)].GetString();
}
/**
* Writes code that does a register assignment to value operation.
* @param reg The destination register to use.
* @param elem The element to use for the operation.
* @param value The code representing the value to assign.
* @param dest_num_components Number of components in the destination.
* @param value_num_components Number of components in the value.
* @param dest_elem Optional, the destination element to use for the operation.
*/
void SetRegister(const Register& reg, u64 elem, const std::string& value,
u64 dest_num_components, u64 value_num_components, u64 dest_elem) {
std::string dest = GetRegister(reg, static_cast<u32>(dest_elem));
if (dest_num_components > 1) {
dest += GetSwizzle(elem);
}
std::string src = '(' + value + ')';
if (value_num_components > 1) {
src += GetSwizzle(elem);
}
shader.AddLine(dest + " = " + src + ';');
}
/// Build the GLSL register list.
void BuildRegisterList() {
for (size_t index = 0; index < Register::NumRegisters; ++index) {
regs.emplace_back(index, suffix);
}
}
/// Generates code representing an input attribute register.
std::string GetInputAttribute(Attribute::Index attribute) {
switch (attribute) {
case Attribute::Index::Position:
return "position";
case Attribute::Index::TessCoordInstanceIDVertexID:
// TODO(Subv): Find out what the values are for the first two elements when inside a
// vertex shader, and what's the value of the fourth element when inside a Tess Eval
// shader.
ASSERT(stage == Maxwell3D::Regs::ShaderStage::Vertex);
return "vec4(0, 0, uintBitsToFloat(gl_InstanceID), uintBitsToFloat(gl_VertexID))";
default:
const u32 index{static_cast<u32>(attribute) -
static_cast<u32>(Attribute::Index::Attribute_0)};
if (attribute >= Attribute::Index::Attribute_0) {
declr_input_attribute.insert(attribute);
return "input_attribute_" + std::to_string(index);
}
LOG_CRITICAL(HW_GPU, "Unhandled input attribute: {}", index);
UNREACHABLE();
}
}
/// Generates code representing an output attribute register.
std::string GetOutputAttribute(Attribute::Index attribute) {
switch (attribute) {
case Attribute::Index::Position:
return "position";
default:
const u32 index{static_cast<u32>(attribute) -
static_cast<u32>(Attribute::Index::Attribute_0)};
if (attribute >= Attribute::Index::Attribute_0) {
declr_output_attribute.insert(attribute);
return "output_attribute_" + std::to_string(index);
}
LOG_CRITICAL(HW_GPU, "Unhandled output attribute: {}", index);
UNREACHABLE();
}
}
/// Generates code to use for a swizzle operation.
static std::string GetSwizzle(u64 elem) {
ASSERT(elem <= 3);
std::string swizzle = ".";
swizzle += "xyzw"[elem];
return swizzle;
}
ShaderWriter& shader;
ShaderWriter& declarations;
std::vector<GLSLRegister> regs;
std::set<Attribute::Index> declr_input_attribute;
std::set<Attribute::Index> declr_output_attribute;
std::array<ConstBufferEntry, Maxwell3D::Regs::MaxConstBuffers> declr_const_buffers;
std::vector<SamplerEntry> used_samplers;
const Maxwell3D::Regs::ShaderStage& stage;
const std::string& suffix;
};
class GLSLGenerator {
public:
GLSLGenerator(const std::set<Subroutine>& subroutines, const ProgramCode& program_code,
u32 main_offset, Maxwell3D::Regs::ShaderStage stage, const std::string& suffix)
: subroutines(subroutines), program_code(program_code), main_offset(main_offset),
stage(stage), suffix(suffix) {
Generate(suffix);
}
std::string GetShaderCode() {
return declarations.GetResult() + shader.GetResult();
}
/// Returns entries in the shader that are useful for external functions
ShaderEntries GetEntries() const {
return {regs.GetConstBuffersDeclarations(), regs.GetSamplers()};
}
private:
/// Gets the Subroutine object corresponding to the specified address.
const Subroutine& GetSubroutine(u32 begin, u32 end) const {
auto iter = subroutines.find(Subroutine{begin, end, suffix});
ASSERT(iter != subroutines.end());
return *iter;
}
/// Generates code representing a 19-bit immediate value
static std::string GetImmediate19(const Instruction& instr) {
return std::to_string(instr.alu.GetImm20_19());
}
/// Generates code representing a 32-bit immediate value
static std::string GetImmediate32(const Instruction& instr) {
return std::to_string(instr.alu.GetImm20_32());
}
/// Generates code representing a texture sampler.
std::string GetSampler(const Sampler& sampler) {
return regs.AccessSampler(sampler);
}
/**
* Adds code that calls a subroutine.
* @param subroutine the subroutine to call.
*/
void CallSubroutine(const Subroutine& subroutine) {
if (subroutine.exit_method == ExitMethod::AlwaysEnd) {
shader.AddLine(subroutine.GetName() + "();");
shader.AddLine("return true;");
} else if (subroutine.exit_method == ExitMethod::Conditional) {
shader.AddLine("if (" + subroutine.GetName() + "()) { return true; }");
} else {
shader.AddLine(subroutine.GetName() + "();");
}
}
/*
* Writes code that assigns a predicate boolean variable.
* @param pred The id of the predicate to write to.
* @param value The expression value to assign to the predicate.
*/
void SetPredicate(u64 pred, const std::string& value) {
using Tegra::Shader::Pred;
// Can't assign to the constant predicate.
ASSERT(pred != static_cast<u64>(Pred::UnusedIndex));
std::string variable = 'p' + std::to_string(pred) + '_' + suffix;
shader.AddLine(variable + " = " + value + ';');
declr_predicates.insert(std::move(variable));
}
/*
* Returns the condition to use in the 'if' for a predicated instruction.
* @param instr Instruction to generate the if condition for.
* @returns string containing the predicate condition.
*/
std::string GetPredicateCondition(u64 index, bool negate) const {
using Tegra::Shader::Pred;
std::string variable;
// Index 7 is used as an 'Always True' condition.
if (index == static_cast<u64>(Pred::UnusedIndex))
variable = "true";
else
variable = 'p' + std::to_string(index) + '_' + suffix;
if (negate) {
return "!(" + variable + ')';
}
return variable;
}
/**
* Returns the comparison string to use to compare two values in the 'set' family of
* instructions.
* @param condition The condition used in the 'set'-family instruction.
* @param op_a First operand to use for the comparison.
* @param op_b Second operand to use for the comparison.
* @returns String corresponding to the GLSL operator that matches the desired comparison.
*/
std::string GetPredicateComparison(Tegra::Shader::PredCondition condition,
const std::string& op_a, const std::string& op_b) const {
using Tegra::Shader::PredCondition;
static const std::unordered_map<PredCondition, const char*> PredicateComparisonStrings = {
{PredCondition::LessThan, "<"}, {PredCondition::Equal, "=="},
{PredCondition::LessEqual, "<="}, {PredCondition::GreaterThan, ">"},
{PredCondition::NotEqual, "!="}, {PredCondition::GreaterEqual, ">="},
{PredCondition::LessThanWithNan, "<"}, {PredCondition::NotEqualWithNan, "!="},
};
const auto& comparison{PredicateComparisonStrings.find(condition)};
ASSERT_MSG(comparison != PredicateComparisonStrings.end(),
"Unknown predicate comparison operation");
std::string predicate{'(' + op_a + ") " + comparison->second + " (" + op_b + ')'};
if (condition == PredCondition::LessThanWithNan ||
condition == PredCondition::NotEqualWithNan) {
predicate += " || isnan(" + op_a + ") || isnan(" + op_b + ')';
}
return predicate;
}
/**
* Returns the operator string to use to combine two predicates in the 'setp' family of
* instructions.
* @params operation The operator used in the 'setp'-family instruction.
* @returns String corresponding to the GLSL operator that matches the desired operator.
*/
std::string GetPredicateCombiner(Tegra::Shader::PredOperation operation) const {
using Tegra::Shader::PredOperation;
static const std::unordered_map<PredOperation, const char*> PredicateOperationStrings = {
{PredOperation::And, "&&"},
{PredOperation::Or, "||"},
{PredOperation::Xor, "^^"},
};
auto op = PredicateOperationStrings.find(operation);
ASSERT_MSG(op != PredicateOperationStrings.end(), "Unknown predicate operation");
return op->second;
}
/*
* Returns whether the instruction at the specified offset is a 'sched' instruction.
* Sched instructions always appear before a sequence of 3 instructions.
*/
bool IsSchedInstruction(u32 offset) const {
// sched instructions appear once every 4 instructions.
static constexpr size_t SchedPeriod = 4;
u32 absolute_offset = offset - main_offset;
return (absolute_offset % SchedPeriod) == 0;
}
void WriteLogicOperation(Register dest, LogicOperation logic_op, const std::string& op_a,
const std::string& op_b) {
switch (logic_op) {
case LogicOperation::And: {
regs.SetRegisterToInteger(dest, true, 0, '(' + op_a + " & " + op_b + ')', 1, 1);
break;
}
case LogicOperation::Or: {
regs.SetRegisterToInteger(dest, true, 0, '(' + op_a + " | " + op_b + ')', 1, 1);
break;
}
case LogicOperation::Xor: {
regs.SetRegisterToInteger(dest, true, 0, '(' + op_a + " ^ " + op_b + ')', 1, 1);
break;
}
case LogicOperation::PassB: {
regs.SetRegisterToInteger(dest, true, 0, op_b, 1, 1);
break;
}
default:
LOG_CRITICAL(HW_GPU, "Unimplemented logic operation: {}", static_cast<u32>(logic_op));
UNREACHABLE();
}
}
/**
* Compiles a single instruction from Tegra to GLSL.
* @param offset the offset of the Tegra shader instruction.
* @return the offset of the next instruction to execute. Usually it is the current offset
* + 1. If the current instruction always terminates the program, returns PROGRAM_END.
*/
u32 CompileInstr(u32 offset) {
// Ignore sched instructions when generating code.
if (IsSchedInstruction(offset)) {
return offset + 1;
}
const Instruction instr = {program_code[offset]};
const auto opcode = OpCode::Decode(instr);
// Decoding failure
if (!opcode) {
LOG_CRITICAL(HW_GPU, "Unhandled instruction: {0:x}", instr.value);
UNREACHABLE();
return offset + 1;
}
shader.AddLine("// " + std::to_string(offset) + ": " + opcode->GetName());
using Tegra::Shader::Pred;
ASSERT_MSG(instr.pred.full_pred != Pred::NeverExecute,
"NeverExecute predicate not implemented");
if (instr.pred.pred_index != static_cast<u64>(Pred::UnusedIndex)) {
shader.AddLine("if (" +
GetPredicateCondition(instr.pred.pred_index, instr.negate_pred != 0) +
')');
shader.AddLine('{');
++shader.scope;
}
switch (opcode->GetType()) {
case OpCode::Type::Arithmetic: {
std::string op_a = regs.GetRegisterAsFloat(instr.gpr8);
if (instr.alu.abs_a) {
op_a = "abs(" + op_a + ')';
}
if (instr.alu.negate_a) {
op_a = "-(" + op_a + ')';
}
std::string op_b;
if (instr.is_b_imm) {
op_b = GetImmediate19(instr);
} else {
if (instr.is_b_gpr) {
op_b = regs.GetRegisterAsFloat(instr.gpr20);
} else {
op_b = regs.GetUniform(instr.cbuf34.index, instr.cbuf34.offset,
GLSLRegister::Type::Float);
}
}
if (instr.alu.abs_b) {
op_b = "abs(" + op_b + ')';
}
if (instr.alu.negate_b) {
op_b = "-(" + op_b + ')';
}
switch (opcode->GetId()) {
case OpCode::Id::MOV_C:
case OpCode::Id::MOV_R: {
regs.SetRegisterToFloat(instr.gpr0, 0, op_b, 1, 1);
break;
}
case OpCode::Id::FMUL_C:
case OpCode::Id::FMUL_R:
case OpCode::Id::FMUL_IMM: {
regs.SetRegisterToFloat(instr.gpr0, 0, op_a + " * " + op_b, 1, 1,
instr.alu.saturate_d);
break;
}
case OpCode::Id::FADD_C:
case OpCode::Id::FADD_R:
case OpCode::Id::FADD_IMM: {
regs.SetRegisterToFloat(instr.gpr0, 0, op_a + " + " + op_b, 1, 1,
instr.alu.saturate_d);
break;
}
case OpCode::Id::MUFU: {
switch (instr.sub_op) {
case SubOp::Cos:
regs.SetRegisterToFloat(instr.gpr0, 0, "cos(" + op_a + ')', 1, 1,
instr.alu.saturate_d);
break;
case SubOp::Sin:
regs.SetRegisterToFloat(instr.gpr0, 0, "sin(" + op_a + ')', 1, 1,
instr.alu.saturate_d);
break;
case SubOp::Ex2:
regs.SetRegisterToFloat(instr.gpr0, 0, "exp2(" + op_a + ')', 1, 1,
instr.alu.saturate_d);
break;
case SubOp::Lg2:
regs.SetRegisterToFloat(instr.gpr0, 0, "log2(" + op_a + ')', 1, 1,
instr.alu.saturate_d);
break;
case SubOp::Rcp:
regs.SetRegisterToFloat(instr.gpr0, 0, "1.0 / " + op_a, 1, 1,
instr.alu.saturate_d);
break;
case SubOp::Rsq:
regs.SetRegisterToFloat(instr.gpr0, 0, "inversesqrt(" + op_a + ')', 1, 1,
instr.alu.saturate_d);
break;
case SubOp::Sqrt:
regs.SetRegisterToFloat(instr.gpr0, 0, "sqrt(" + op_a + ')', 1, 1,
instr.alu.saturate_d);
break;
default:
LOG_CRITICAL(HW_GPU, "Unhandled MUFU sub op: {0:x}",
static_cast<unsigned>(instr.sub_op.Value()));
UNREACHABLE();
}
break;
}
case OpCode::Id::FMNMX_C:
case OpCode::Id::FMNMX_R:
case OpCode::Id::FMNMX_IMM: {
std::string condition =
GetPredicateCondition(instr.alu.fmnmx.pred, instr.alu.fmnmx.negate_pred != 0);
std::string parameters = op_a + ',' + op_b;
regs.SetRegisterToFloat(instr.gpr0, 0,
'(' + condition + ") ? min(" + parameters + ") : max(" +
parameters + ')',
1, 1);
break;
}
case OpCode::Id::RRO_C:
case OpCode::Id::RRO_R:
case OpCode::Id::RRO_IMM: {
// Currently RRO is only implemented as a register move.
// Usage of `abs_b` and `negate_b` here should also be correct.
regs.SetRegisterToFloat(instr.gpr0, 0, op_b, 1, 1);
LOG_WARNING(HW_GPU, "RRO instruction is incomplete");
break;
}
default: {
LOG_CRITICAL(HW_GPU, "Unhandled arithmetic instruction: {}", opcode->GetName());
UNREACHABLE();
}
}
break;
}
case OpCode::Type::ArithmeticImmediate: {
switch (opcode->GetId()) {
case OpCode::Id::MOV32_IMM: {
regs.SetRegisterToFloat(instr.gpr0, 0, GetImmediate32(instr), 1, 1);
break;
}
case OpCode::Id::FMUL32_IMM: {
regs.SetRegisterToFloat(
instr.gpr0, 0,
regs.GetRegisterAsFloat(instr.gpr8) + " * " + GetImmediate32(instr), 1, 1);
break;
}
case OpCode::Id::FADD32I: {
std::string op_a = regs.GetRegisterAsFloat(instr.gpr8);
std::string op_b = GetImmediate32(instr);
if (instr.fadd32i.abs_a) {
op_a = "abs(" + op_a + ')';
}
if (instr.fadd32i.negate_a) {
op_a = "-(" + op_a + ')';
}
if (instr.fadd32i.abs_b) {
op_b = "abs(" + op_b + ')';
}
if (instr.fadd32i.negate_b) {
op_b = "-(" + op_b + ')';
}
regs.SetRegisterToFloat(instr.gpr0, 0, op_a + " + " + op_b, 1, 1);
break;
}
}
break;
}
case OpCode::Type::Bfe: {
ASSERT_MSG(!instr.bfe.negate_b, "Unimplemented");
std::string op_a = instr.bfe.negate_a ? "-" : "";
op_a += regs.GetRegisterAsInteger(instr.gpr8);
switch (opcode->GetId()) {
case OpCode::Id::BFE_IMM: {
std::string inner_shift =
'(' + op_a + " << " + std::to_string(instr.bfe.GetLeftShiftValue()) + ')';
std::string outer_shift =
'(' + inner_shift + " >> " +
std::to_string(instr.bfe.GetLeftShiftValue() + instr.bfe.shift_position) + ')';
regs.SetRegisterToInteger(instr.gpr0, true, 0, outer_shift, 1, 1);
break;
}
default: {
LOG_CRITICAL(HW_GPU, "Unhandled BFE instruction: {}", opcode->GetName());
UNREACHABLE();
}
}
break;
}
case OpCode::Type::Shift: {
std::string op_a = regs.GetRegisterAsInteger(instr.gpr8, 0, true);
std::string op_b;
if (instr.is_b_imm) {
op_b += '(' + std::to_string(instr.alu.GetSignedImm20_20()) + ')';
} else {
if (instr.is_b_gpr) {
op_b += regs.GetRegisterAsInteger(instr.gpr20);
} else {
op_b += regs.GetUniform(instr.cbuf34.index, instr.cbuf34.offset,
GLSLRegister::Type::Integer);
}
}
switch (opcode->GetId()) {
case OpCode::Id::SHR_C:
case OpCode::Id::SHR_R:
case OpCode::Id::SHR_IMM: {
if (!instr.shift.is_signed) {
// Logical shift right
op_a = "uint(" + op_a + ')';
}
// Cast to int is superfluous for arithmetic shift, it's only for a logical shift
regs.SetRegisterToInteger(instr.gpr0, true, 0, "int(" + op_a + " >> " + op_b + ')',
1, 1);
break;
}
case OpCode::Id::SHL_C:
case OpCode::Id::SHL_R:
case OpCode::Id::SHL_IMM:
regs.SetRegisterToInteger(instr.gpr0, true, 0, op_a + " << " + op_b, 1, 1);
break;
default: {
LOG_CRITICAL(HW_GPU, "Unhandled shift instruction: {}", opcode->GetName());
UNREACHABLE();
}
}
break;
}
case OpCode::Type::ArithmeticIntegerImmediate: {
std::string op_a = regs.GetRegisterAsInteger(instr.gpr8);
std::string op_b = std::to_string(instr.alu.imm20_32.Value());
switch (opcode->GetId()) {
case OpCode::Id::IADD32I:
if (instr.iadd32i.negate_a)
op_a = "-(" + op_a + ')';
regs.SetRegisterToInteger(instr.gpr0, true, 0, op_a + " + " + op_b, 1, 1,
instr.iadd32i.saturate != 0);
break;
case OpCode::Id::LOP32I: {
if (instr.alu.lop32i.invert_a)
op_a = "~(" + op_a + ')';
if (instr.alu.lop32i.invert_b)
op_b = "~(" + op_b + ')';
WriteLogicOperation(instr.gpr0, instr.alu.lop32i.operation, op_a, op_b);
break;
}
default: {
LOG_CRITICAL(HW_GPU, "Unhandled ArithmeticIntegerImmediate instruction: {}",
opcode->GetName());
UNREACHABLE();
}
}
break;
}
case OpCode::Type::ArithmeticInteger: {
std::string op_a = regs.GetRegisterAsInteger(instr.gpr8);
std::string op_b;
if (instr.is_b_imm) {
op_b += '(' + std::to_string(instr.alu.GetSignedImm20_20()) + ')';
} else {
if (instr.is_b_gpr) {
op_b += regs.GetRegisterAsInteger(instr.gpr20);
} else {
op_b += regs.GetUniform(instr.cbuf34.index, instr.cbuf34.offset,
GLSLRegister::Type::Integer);
}
}
switch (opcode->GetId()) {
case OpCode::Id::IADD_C:
case OpCode::Id::IADD_R:
case OpCode::Id::IADD_IMM: {
if (instr.alu_integer.negate_a)
op_a = "-(" + op_a + ')';
if (instr.alu_integer.negate_b)
op_b = "-(" + op_b + ')';
regs.SetRegisterToInteger(instr.gpr0, true, 0, op_a + " + " + op_b, 1, 1,
instr.alu.saturate_d);
break;
}
case OpCode::Id::ISCADD_C:
case OpCode::Id::ISCADD_R:
case OpCode::Id::ISCADD_IMM: {
if (instr.alu_integer.negate_a)
op_a = "-(" + op_a + ')';
if (instr.alu_integer.negate_b)
op_b = "-(" + op_b + ')';
std::string shift = std::to_string(instr.alu_integer.shift_amount.Value());
regs.SetRegisterToInteger(instr.gpr0, true, 0,
"((" + op_a + " << " + shift + ") + " + op_b + ')', 1, 1);
break;
}
case OpCode::Id::SEL_C:
case OpCode::Id::SEL_R:
case OpCode::Id::SEL_IMM: {
std::string condition =
GetPredicateCondition(instr.sel.pred, instr.sel.neg_pred != 0);
regs.SetRegisterToInteger(instr.gpr0, true, 0,
'(' + condition + ") ? " + op_a + " : " + op_b, 1, 1);
break;
}
case OpCode::Id::LOP_C:
case OpCode::Id::LOP_R:
case OpCode::Id::LOP_IMM: {
ASSERT_MSG(!instr.alu.lop.unk44, "Unimplemented");
ASSERT_MSG(instr.alu.lop.pred48 == Pred::UnusedIndex, "Unimplemented");
if (instr.alu.lop.invert_a)
op_a = "~(" + op_a + ')';
if (instr.alu.lop.invert_b)
op_b = "~(" + op_b + ')';
WriteLogicOperation(instr.gpr0, instr.alu.lop.operation, op_a, op_b);
break;
}
case OpCode::Id::IMNMX_C:
case OpCode::Id::IMNMX_R:
case OpCode::Id::IMNMX_IMM: {
ASSERT_MSG(instr.imnmx.exchange == Tegra::Shader::IMinMaxExchange::None,
"Unimplemented");
std::string condition =
GetPredicateCondition(instr.imnmx.pred, instr.imnmx.negate_pred != 0);
std::string parameters = op_a + ',' + op_b;
regs.SetRegisterToInteger(instr.gpr0, instr.imnmx.is_signed, 0,
'(' + condition + ") ? min(" + parameters + ") : max(" +
parameters + ')',
1, 1);
break;
}
default: {
LOG_CRITICAL(HW_GPU, "Unhandled ArithmeticInteger instruction: {}",
opcode->GetName());
UNREACHABLE();
}
}
break;
}
case OpCode::Type::Ffma: {
std::string op_a = regs.GetRegisterAsFloat(instr.gpr8);
std::string op_b = instr.ffma.negate_b ? "-" : "";
std::string op_c = instr.ffma.negate_c ? "-" : "";
switch (opcode->GetId()) {
case OpCode::Id::FFMA_CR: {
op_b += regs.GetUniform(instr.cbuf34.index, instr.cbuf34.offset,
GLSLRegister::Type::Float);
op_c += regs.GetRegisterAsFloat(instr.gpr39);
break;
}
case OpCode::Id::FFMA_RR: {
op_b += regs.GetRegisterAsFloat(instr.gpr20);
op_c += regs.GetRegisterAsFloat(instr.gpr39);
break;
}
case OpCode::Id::FFMA_RC: {
op_b += regs.GetRegisterAsFloat(instr.gpr39);
op_c += regs.GetUniform(instr.cbuf34.index, instr.cbuf34.offset,
GLSLRegister::Type::Float);
break;
}
case OpCode::Id::FFMA_IMM: {
op_b += GetImmediate19(instr);
op_c += regs.GetRegisterAsFloat(instr.gpr39);
break;
}
default: {
LOG_CRITICAL(HW_GPU, "Unhandled FFMA instruction: {}", opcode->GetName());
UNREACHABLE();
}
}
regs.SetRegisterToFloat(instr.gpr0, 0, op_a + " * " + op_b + " + " + op_c, 1, 1,
instr.alu.saturate_d);
break;
}
case OpCode::Type::Conversion: {
ASSERT_MSG(!instr.conversion.negate_a, "Unimplemented");
switch (opcode->GetId()) {
case OpCode::Id::I2I_R: {
ASSERT_MSG(!instr.conversion.selector, "Unimplemented");
std::string op_a = regs.GetRegisterAsInteger(
instr.gpr20, 0, instr.conversion.is_input_signed, instr.conversion.src_size);
if (instr.conversion.abs_a) {
op_a = "abs(" + op_a + ')';
}
regs.SetRegisterToInteger(instr.gpr0, instr.conversion.is_output_signed, 0, op_a, 1,
1, instr.alu.saturate_d, 0, instr.conversion.dest_size);
break;
}
case OpCode::Id::I2F_R: {
ASSERT_MSG(instr.conversion.dest_size == Register::Size::Word, "Unimplemented");
ASSERT_MSG(!instr.conversion.selector, "Unimplemented");
std::string op_a = regs.GetRegisterAsInteger(
instr.gpr20, 0, instr.conversion.is_input_signed, instr.conversion.src_size);
if (instr.conversion.abs_a) {
op_a = "abs(" + op_a + ')';
}
regs.SetRegisterToFloat(instr.gpr0, 0, op_a, 1, 1);
break;
}
case OpCode::Id::F2F_R: {
ASSERT_MSG(instr.conversion.dest_size == Register::Size::Word, "Unimplemented");
ASSERT_MSG(instr.conversion.src_size == Register::Size::Word, "Unimplemented");
std::string op_a = regs.GetRegisterAsFloat(instr.gpr20);
switch (instr.conversion.f2f.rounding) {
case Tegra::Shader::F2fRoundingOp::None:
break;
case Tegra::Shader::F2fRoundingOp::Round:
op_a = "roundEven(" + op_a + ')';
break;
case Tegra::Shader::F2fRoundingOp::Floor:
op_a = "floor(" + op_a + ')';
break;
case Tegra::Shader::F2fRoundingOp::Ceil:
op_a = "ceil(" + op_a + ')';
break;
case Tegra::Shader::F2fRoundingOp::Trunc:
op_a = "trunc(" + op_a + ')';
break;
default:
LOG_CRITICAL(HW_GPU, "Unimplemented f2f rounding mode {}",
static_cast<u32>(instr.conversion.f2f.rounding.Value()));
UNREACHABLE();
break;
}
if (instr.conversion.abs_a) {
op_a = "abs(" + op_a + ')';
}
regs.SetRegisterToFloat(instr.gpr0, 0, op_a, 1, 1, instr.alu.saturate_d);
break;
}
case OpCode::Id::F2I_R: {
ASSERT_MSG(instr.conversion.src_size == Register::Size::Word, "Unimplemented");
std::string op_a = regs.GetRegisterAsFloat(instr.gpr20);
if (instr.conversion.abs_a) {
op_a = "abs(" + op_a + ')';
}
switch (instr.conversion.f2i.rounding) {
case Tegra::Shader::F2iRoundingOp::None:
break;
case Tegra::Shader::F2iRoundingOp::Floor:
op_a = "floor(" + op_a + ')';
break;
case Tegra::Shader::F2iRoundingOp::Ceil:
op_a = "ceil(" + op_a + ')';
break;
case Tegra::Shader::F2iRoundingOp::Trunc:
op_a = "trunc(" + op_a + ')';
break;
default:
LOG_CRITICAL(HW_GPU, "Unimplemented f2i rounding mode {}",
static_cast<u32>(instr.conversion.f2i.rounding.Value()));
UNREACHABLE();
break;
}
if (instr.conversion.is_output_signed) {
op_a = "int(" + op_a + ')';
} else {
op_a = "uint(" + op_a + ')';
}
regs.SetRegisterToInteger(instr.gpr0, instr.conversion.is_output_signed, 0, op_a, 1,
1, false, 0, instr.conversion.dest_size);
break;
}
default: {
LOG_CRITICAL(HW_GPU, "Unhandled conversion instruction: {}", opcode->GetName());
UNREACHABLE();
}
}
break;
}
case OpCode::Type::Memory: {
switch (opcode->GetId()) {
case OpCode::Id::LD_A: {
ASSERT_MSG(instr.attribute.fmt20.size == 0, "untested");
regs.SetRegisterToInputAttibute(instr.gpr0, instr.attribute.fmt20.element,
instr.attribute.fmt20.index);
break;
}
case OpCode::Id::LD_C: {
ASSERT_MSG(instr.ld_c.unknown == 0, "Unimplemented");
std::string op_a =
regs.GetUniformIndirect(instr.cbuf36.index, instr.cbuf36.offset + 0, instr.gpr8,
GLSLRegister::Type::Float);
std::string op_b =
regs.GetUniformIndirect(instr.cbuf36.index, instr.cbuf36.offset + 4, instr.gpr8,
GLSLRegister::Type::Float);
switch (instr.ld_c.type.Value()) {
case Tegra::Shader::UniformType::Single:
regs.SetRegisterToFloat(instr.gpr0, 0, op_a, 1, 1);
break;
case Tegra::Shader::UniformType::Double:
regs.SetRegisterToFloat(instr.gpr0, 0, op_a, 1, 1);
regs.SetRegisterToFloat(instr.gpr0.Value() + 1, 0, op_b, 1, 1);
break;
default:
LOG_CRITICAL(HW_GPU, "Unhandled type: {}",
static_cast<unsigned>(instr.ld_c.type.Value()));
UNREACHABLE();
}
break;
}
case OpCode::Id::ST_A: {
ASSERT_MSG(instr.attribute.fmt20.size == 0, "untested");
regs.SetOutputAttributeToRegister(instr.attribute.fmt20.index,
instr.attribute.fmt20.element, instr.gpr0);
break;
}
case OpCode::Id::TEX: {
const std::string op_a = regs.GetRegisterAsFloat(instr.gpr8);
const std::string op_b = regs.GetRegisterAsFloat(instr.gpr8.Value() + 1);
const std::string sampler = GetSampler(instr.sampler);
const std::string coord = "vec2 coords = vec2(" + op_a + ", " + op_b + ");";
// Add an extra scope and declare the texture coords inside to prevent
// overwriting them in case they are used as outputs of the texs instruction.
shader.AddLine("{");
++shader.scope;
shader.AddLine(coord);
const std::string texture = "texture(" + sampler + ", coords)";
size_t dest_elem{};
for (size_t elem = 0; elem < 4; ++elem) {
if (!instr.tex.IsComponentEnabled(elem)) {
// Skip disabled components
continue;
}
regs.SetRegisterToFloat(instr.gpr0, elem, texture, 1, 4, false, dest_elem);
++dest_elem;
}
--shader.scope;
shader.AddLine("}");
break;
}
case OpCode::Id::TEXS: {
const std::string op_a = regs.GetRegisterAsFloat(instr.gpr8);
const std::string op_b = regs.GetRegisterAsFloat(instr.gpr20);
const std::string sampler = GetSampler(instr.sampler);
const std::string coord = "vec2 coords = vec2(" + op_a + ", " + op_b + ");";
// Add an extra scope and declare the texture coords inside to prevent
// overwriting them in case they are used as outputs of the texs instruction.
shader.AddLine("{");
++shader.scope;
shader.AddLine(coord);
const std::string texture = "texture(" + sampler + ", coords)";
// TEXS has two destination registers. RG goes into gpr0+0 and gpr0+1, and BA
// goes into gpr28+0 and gpr28+1
size_t texs_offset{};
for (const auto& dest : {instr.gpr0.Value(), instr.gpr28.Value()}) {
for (unsigned elem = 0; elem < 2; ++elem) {
if (!instr.texs.IsComponentEnabled(elem)) {
// Skip disabled components
continue;
}
regs.SetRegisterToFloat(dest, elem + texs_offset, texture, 1, 4, false,
elem);
}
if (!instr.texs.HasTwoDestinations()) {
// Skip the second destination
break;
}
texs_offset += 2;
}
--shader.scope;
shader.AddLine("}");
break;
}
default: {
LOG_CRITICAL(HW_GPU, "Unhandled memory instruction: {}", opcode->GetName());
UNREACHABLE();
}
}
break;
}
case OpCode::Type::FloatSetPredicate: {
std::string op_a = instr.fsetp.neg_a ? "-" : "";
op_a += regs.GetRegisterAsFloat(instr.gpr8);
if (instr.fsetp.abs_a) {
op_a = "abs(" + op_a + ')';
}
std::string op_b{};
if (instr.is_b_imm) {
if (instr.fsetp.neg_b) {
// Only the immediate version of fsetp has a neg_b bit.
op_b += '-';
}
op_b += '(' + GetImmediate19(instr) + ')';
} else {
if (instr.is_b_gpr) {
op_b += regs.GetRegisterAsFloat(instr.gpr20);
} else {
op_b += regs.GetUniform(instr.cbuf34.index, instr.cbuf34.offset,
GLSLRegister::Type::Float);
}
}
if (instr.fsetp.abs_b) {
op_b = "abs(" + op_b + ')';
}
// We can't use the constant predicate as destination.
ASSERT(instr.fsetp.pred3 != static_cast<u64>(Pred::UnusedIndex));
std::string second_pred =
GetPredicateCondition(instr.fsetp.pred39, instr.fsetp.neg_pred != 0);
std::string combiner = GetPredicateCombiner(instr.fsetp.op);
std::string predicate = GetPredicateComparison(instr.fsetp.cond, op_a, op_b);
// Set the primary predicate to the result of Predicate OP SecondPredicate
SetPredicate(instr.fsetp.pred3,
'(' + predicate + ") " + combiner + " (" + second_pred + ')');
if (instr.fsetp.pred0 != static_cast<u64>(Pred::UnusedIndex)) {
// Set the secondary predicate to the result of !Predicate OP SecondPredicate,
// if enabled
SetPredicate(instr.fsetp.pred0,
"!(" + predicate + ") " + combiner + " (" + second_pred + ')');
}
break;
}
case OpCode::Type::IntegerSetPredicate: {
std::string op_a = regs.GetRegisterAsInteger(instr.gpr8, 0, instr.isetp.is_signed);
std::string op_b;
if (instr.is_b_imm) {
op_b += '(' + std::to_string(instr.alu.GetSignedImm20_20()) + ')';
} else {
if (instr.is_b_gpr) {
op_b += regs.GetRegisterAsInteger(instr.gpr20, 0, instr.isetp.is_signed);
} else {
op_b += regs.GetUniform(instr.cbuf34.index, instr.cbuf34.offset,
GLSLRegister::Type::Integer);
}
}
// We can't use the constant predicate as destination.
ASSERT(instr.isetp.pred3 != static_cast<u64>(Pred::UnusedIndex));
std::string second_pred =
GetPredicateCondition(instr.isetp.pred39, instr.isetp.neg_pred != 0);
std::string combiner = GetPredicateCombiner(instr.isetp.op);
std::string predicate = GetPredicateComparison(instr.isetp.cond, op_a, op_b);
// Set the primary predicate to the result of Predicate OP SecondPredicate
SetPredicate(instr.isetp.pred3,
'(' + predicate + ") " + combiner + " (" + second_pred + ')');
if (instr.isetp.pred0 != static_cast<u64>(Pred::UnusedIndex)) {
// Set the secondary predicate to the result of !Predicate OP SecondPredicate,
// if enabled
SetPredicate(instr.isetp.pred0,
"!(" + predicate + ") " + combiner + " (" + second_pred + ')');
}
break;
}
case OpCode::Type::PredicateSetPredicate: {
std::string op_a =
GetPredicateCondition(instr.psetp.pred12, instr.psetp.neg_pred12 != 0);
std::string op_b =
GetPredicateCondition(instr.psetp.pred29, instr.psetp.neg_pred29 != 0);
// We can't use the constant predicate as destination.
ASSERT(instr.psetp.pred3 != static_cast<u64>(Pred::UnusedIndex));
std::string second_pred =
GetPredicateCondition(instr.psetp.pred39, instr.psetp.neg_pred39 != 0);
std::string combiner = GetPredicateCombiner(instr.psetp.op);
std::string predicate =
'(' + op_a + ") " + GetPredicateCombiner(instr.psetp.cond) + " (" + op_b + ')';
// Set the primary predicate to the result of Predicate OP SecondPredicate
SetPredicate(instr.psetp.pred3,
'(' + predicate + ") " + combiner + " (" + second_pred + ')');
if (instr.psetp.pred0 != static_cast<u64>(Pred::UnusedIndex)) {
// Set the secondary predicate to the result of !Predicate OP SecondPredicate,
// if enabled
SetPredicate(instr.psetp.pred0,
"!(" + predicate + ") " + combiner + " (" + second_pred + ')');
}
break;
}
case OpCode::Type::FloatSet: {
std::string op_a = instr.fset.neg_a ? "-" : "";
op_a += regs.GetRegisterAsFloat(instr.gpr8);
if (instr.fset.abs_a) {
op_a = "abs(" + op_a + ')';
}
std::string op_b = instr.fset.neg_b ? "-" : "";
if (instr.is_b_imm) {
std::string imm = GetImmediate19(instr);
if (instr.fset.neg_imm)
op_b += "(-" + imm + ')';
else
op_b += imm;
} else {
if (instr.is_b_gpr) {
op_b += regs.GetRegisterAsFloat(instr.gpr20);
} else {
op_b += regs.GetUniform(instr.cbuf34.index, instr.cbuf34.offset,
GLSLRegister::Type::Float);
}
}
if (instr.fset.abs_b) {
op_b = "abs(" + op_b + ')';
}
// The fset instruction sets a register to 1.0 or -1 (depending on the bf bit) if the
// condition is true, and to 0 otherwise.
std::string second_pred =
GetPredicateCondition(instr.fset.pred39, instr.fset.neg_pred != 0);
std::string combiner = GetPredicateCombiner(instr.fset.op);
std::string predicate = "((" + GetPredicateComparison(instr.fset.cond, op_a, op_b) +
") " + combiner + " (" + second_pred + "))";
if (instr.fset.bf) {
regs.SetRegisterToFloat(instr.gpr0, 0, predicate + " ? 1.0 : 0.0", 1, 1);
} else {
regs.SetRegisterToInteger(instr.gpr0, false, 0, predicate + " ? 0xFFFFFFFF : 0", 1,
1);
}
break;
}
case OpCode::Type::IntegerSet: {
std::string op_a = regs.GetRegisterAsInteger(instr.gpr8, 0, instr.iset.is_signed);
std::string op_b;
if (instr.is_b_imm) {
op_b = std::to_string(instr.alu.GetSignedImm20_20());
} else {
if (instr.is_b_gpr) {
op_b = regs.GetRegisterAsInteger(instr.gpr20, 0, instr.iset.is_signed);
} else {
op_b = regs.GetUniform(instr.cbuf34.index, instr.cbuf34.offset,
GLSLRegister::Type::Integer);
}
}
// The iset instruction sets a register to 1.0 or -1 (depending on the bf bit) if the
// condition is true, and to 0 otherwise.
std::string second_pred =
GetPredicateCondition(instr.iset.pred39, instr.iset.neg_pred != 0);
std::string combiner = GetPredicateCombiner(instr.iset.op);
std::string predicate = "((" + GetPredicateComparison(instr.iset.cond, op_a, op_b) +
") " + combiner + " (" + second_pred + "))";
if (instr.iset.bf) {
regs.SetRegisterToFloat(instr.gpr0, 0, predicate + " ? 1.0 : 0.0", 1, 1);
} else {
regs.SetRegisterToInteger(instr.gpr0, false, 0, predicate + " ? 0xFFFFFFFF : 0", 1,
1);
}
break;
}
default: {
switch (opcode->GetId()) {
case OpCode::Id::EXIT: {
// Final color output is currently hardcoded to GPR0-3 for fragment shaders
if (stage == Maxwell3D::Regs::ShaderStage::Fragment) {
shader.AddLine("color.r = " + regs.GetRegisterAsFloat(0) + ';');
shader.AddLine("color.g = " + regs.GetRegisterAsFloat(1) + ';');
shader.AddLine("color.b = " + regs.GetRegisterAsFloat(2) + ';');
shader.AddLine("color.a = " + regs.GetRegisterAsFloat(3) + ';');
}
switch (instr.flow.cond) {
case Tegra::Shader::FlowCondition::Always:
shader.AddLine("return true;");
if (instr.pred.pred_index == static_cast<u64>(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.
offset = PROGRAM_END - 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
LOG_CRITICAL(HW_GPU, "Skipping unknown FlowCondition::Fcsm_Tr");
break;
default:
LOG_CRITICAL(HW_GPU, "Unhandled flow condition: {}",
static_cast<u32>(instr.flow.cond.Value()));
UNREACHABLE();
}
break;
}
case OpCode::Id::KIL: {
ASSERT(instr.flow.cond == Tegra::Shader::FlowCondition::Always);
shader.AddLine("discard;");
break;
}
case OpCode::Id::BRA: {
ASSERT_MSG(instr.bra.constant_buffer == 0,
"BRA with constant buffers are not implemented");
u32 target = offset + instr.bra.GetBranchTarget();
shader.AddLine("{ jmp_to = " + std::to_string(target) + "u; break; }");
break;
}
case OpCode::Id::IPA: {
const auto& attribute = instr.attribute.fmt28;
regs.SetRegisterToInputAttibute(instr.gpr0, attribute.element, attribute.index);
break;
}
case OpCode::Id::SSY: {
// The SSY opcode tells the GPU where to re-converge divergent execution paths, we
// can ignore this when generating GLSL code.
break;
}
case OpCode::Id::SYNC:
ASSERT(instr.flow.cond == Tegra::Shader::FlowCondition::Always);
case OpCode::Id::DEPBAR: {
// TODO(Subv): Find out if we actually have to care about these instructions or if
// the GLSL compiler takes care of that for us.
LOG_WARNING(HW_GPU, "DEPBAR/SYNC instruction is stubbed");
break;
}
default: {
LOG_CRITICAL(HW_GPU, "Unhandled instruction: {}", opcode->GetName());
UNREACHABLE();
}
}
break;
}
}
// Close the predicate condition scope.
if (instr.pred.pred_index != static_cast<u64>(Pred::UnusedIndex)) {
--shader.scope;
shader.AddLine('}');
}
return offset + 1;
}
/**
* Compiles a range of instructions from Tegra to GLSL.
* @param begin the offset of the starting instruction.
* @param end the offset where the compilation should stop (exclusive).
* @return the offset of the next instruction to compile. PROGRAM_END if the program
* terminates.
*/
u32 CompileRange(u32 begin, u32 end) {
u32 program_counter;
for (program_counter = begin; program_counter < (begin > end ? PROGRAM_END : end);) {
program_counter = CompileInstr(program_counter);
}
return program_counter;
}
void Generate(const std::string& suffix) {
// Add declarations for all subroutines
for (const auto& subroutine : subroutines) {
shader.AddLine("bool " + subroutine.GetName() + "();");
}
shader.AddNewLine();
// Add the main entry point
shader.AddLine("bool exec_" + suffix + "() {");
++shader.scope;
CallSubroutine(GetSubroutine(main_offset, PROGRAM_END));
--shader.scope;
shader.AddLine("}\n");
// Add definitions for all subroutines
for (const auto& subroutine : subroutines) {
std::set<u32> labels = subroutine.labels;
shader.AddLine("bool " + subroutine.GetName() + "() {");
++shader.scope;
if (labels.empty()) {
if (CompileRange(subroutine.begin, subroutine.end) != PROGRAM_END) {
shader.AddLine("return false;");
}
} else {
labels.insert(subroutine.begin);
shader.AddLine("uint jmp_to = " + std::to_string(subroutine.begin) + "u;");
shader.AddLine("while (true) {");
++shader.scope;
shader.AddLine("switch (jmp_to) {");
for (auto label : labels) {
shader.AddLine("case " + std::to_string(label) + "u: {");
++shader.scope;
auto next_it = labels.lower_bound(label + 1);
u32 next_label = next_it == labels.end() ? subroutine.end : *next_it;
u32 compile_end = CompileRange(label, next_label);
if (compile_end > next_label && compile_end != PROGRAM_END) {
// This happens only when there is a label inside a IF/LOOP block
shader.AddLine("{ jmp_to = " + std::to_string(compile_end) + "u; break; }");
labels.emplace(compile_end);
}
--shader.scope;
shader.AddLine('}');
}
shader.AddLine("default: return false;");
shader.AddLine('}');
--shader.scope;
shader.AddLine('}');
shader.AddLine("return false;");
}
--shader.scope;
shader.AddLine("}\n");
DEBUG_ASSERT(shader.scope == 0);
}
GenerateDeclarations();
}
/// Add declarations for registers
void GenerateDeclarations() {
regs.GenerateDeclarations(suffix);
for (const auto& pred : declr_predicates) {
declarations.AddLine("bool " + pred + " = false;");
}
declarations.AddNewLine();
}
private:
const std::set<Subroutine>& subroutines;
const ProgramCode& program_code;
const u32 main_offset;
Maxwell3D::Regs::ShaderStage stage;
const std::string& suffix;
ShaderWriter shader;
ShaderWriter declarations;
GLSLRegisterManager regs{shader, declarations, stage, suffix};
// Declarations
std::set<std::string> declr_predicates;
}; // namespace Decompiler
std::string GetCommonDeclarations() {
std::string declarations;
declarations += "#define MAX_CONSTBUFFER_ELEMENTS " +
std::to_string(RasterizerOpenGL::MaxConstbufferSize / (sizeof(GLvec4)));
declarations += '\n';
return declarations;
}
boost::optional<ProgramResult> DecompileProgram(const ProgramCode& program_code, u32 main_offset,
Maxwell3D::Regs::ShaderStage stage,
const std::string& suffix) {
try {
auto subroutines = ControlFlowAnalyzer(program_code, main_offset, suffix).GetSubroutines();
GLSLGenerator generator(subroutines, program_code, main_offset, stage, suffix);
return ProgramResult{generator.GetShaderCode(), generator.GetEntries()};
} catch (const DecompileFail& exception) {
LOG_ERROR(HW_GPU, "Shader decompilation failed: {}", exception.what());
}
return boost::none;
}
} // namespace GLShader::Decompiler