// Copyright 2018 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <string>
#include <string_view>
#include <variant>
#include <fmt/format.h>
#include "common/alignment.h"
#include "common/assert.h"
#include "common/common_types.h"
#include "video_core/engines/maxwell_3d.h"
#include "video_core/shader/glsl_decompiler.h"
#include "video_core/shader/shader_ir.h"
namespace OpenGL::GLShader {
using Tegra::Shader::Attribute;
using Tegra::Shader::Header;
using Tegra::Shader::IpaInterpMode;
using Tegra::Shader::IpaMode;
using Tegra::Shader::IpaSampleMode;
using namespace VideoCommon::Shader;
using Maxwell = Tegra::Engines::Maxwell3D::Regs;
using ShaderStage = Tegra::Engines::Maxwell3D::Regs::ShaderStage;
using Operation = const OperationNode&;
enum : u32 { POSITION_VARYING_LOCATION = 0, GENERIC_VARYING_START_LOCATION = 1 };
constexpr u32 MAX_CONSTBUFFER_ELEMENTS = 65536 / 16; // TODO(Rodrigo): Use rasterizer's value
enum class Type { Bool, Float, Int, Uint, HalfFloat };
class ShaderWriter {
public:
void AddExpression(std::string_view text) {
DEBUG_ASSERT(scope >= 0);
if (!text.empty()) {
AppendIndentation();
}
shader_source += text;
}
void AddLine(std::string_view text) {
AddExpression(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 GenerateTemporal() {
std::string temporal = "tmp";
temporal += std::to_string(temporal_index++);
return temporal;
}
std::string GetResult() {
return std::move(shader_source);
}
s32 scope = 0;
private:
void AppendIndentation() {
shader_source.append(static_cast<std::size_t>(scope) * 4, ' ');
}
std::string shader_source;
u32 temporal_index = 1;
};
/// Generates code to use for a swizzle operation.
static std::string GetSwizzle(u32 elem) {
ASSERT(elem <= 3);
std::string swizzle = ".";
swizzle += "xyzw"[elem];
return swizzle;
}
static bool IsPrecise(Operation operand) {
const auto& meta = operand.GetMeta();
if (std::holds_alternative<MetaArithmetic>(meta)) {
return std::get<MetaArithmetic>(meta).precise;
}
if (std::holds_alternative<MetaHalfArithmetic>(meta)) {
return std::get<MetaHalfArithmetic>(meta).precise;
}
return false;
}
static bool IsPrecise(Node node) {
if (!std::holds_alternative<OperationNode>(*node)) {
return false;
}
return IsPrecise(std::get<OperationNode>(*node));
}
class GLSLDecompiler final {
public:
explicit GLSLDecompiler(const ShaderIR& ir, ShaderStage stage, std::string suffix)
: ir{ir}, stage{stage}, suffix{suffix}, header{ir.GetHeader()} {}
void Decompile() {
DeclareVertex();
DeclareRegisters();
DeclarePredicates();
DeclareLocalMemory();
DeclareInternalFlags();
DeclareInputAttributes();
DeclareOutputAttributes();
DeclareConstantBuffers();
DeclareSamplers();
code.AddLine("void execute_" + suffix + "() {");
++code.scope;
// VM's program counter
const auto first_address = ir.GetBasicBlocks().begin()->first;
code.AddLine("uint jmp_to = " + std::to_string(first_address) + "u;");
// TODO(Subv): Figure out the actual depth of the flow stack, for now it seems
// unlikely that shaders will use 20 nested SSYs and PBKs.
constexpr u32 FLOW_STACK_SIZE = 20;
code.AddLine(fmt::format("uint flow_stack[{}];", FLOW_STACK_SIZE));
code.AddLine("uint flow_stack_top = 0u;");
code.AddLine("while (true) {");
++code.scope;
code.AddLine("switch (jmp_to) {");
for (const auto& pair : ir.GetBasicBlocks()) {
const auto [address, bb] = pair;
code.AddLine(fmt::format("case 0x{:x}u: {{", address));
++code.scope;
VisitBasicBlock(bb);
--code.scope;
code.AddLine('}');
}
code.AddLine("default: return;");
code.AddLine('}');
for (std::size_t i = 0; i < 2; ++i) {
--code.scope;
code.AddLine('}');
}
}
std::string GetResult() {
return code.GetResult();
}
ShaderEntries GetShaderEntries() const {
ShaderEntries entries;
for (const auto& cbuf : ir.GetConstantBuffers()) {
ConstBufferEntry desc(cbuf.second, stage, GetConstBufferBlock(cbuf.first), cbuf.first);
entries.const_buffers.push_back(desc);
}
for (const auto& sampler : ir.GetSamplers()) {
SamplerEntry desc(sampler, stage, GetSampler(sampler));
entries.samplers.push_back(desc);
}
entries.clip_distances = ir.GetClipDistances();
entries.shader_length = ir.GetLength();
return entries;
}
private:
using OperationDecompilerFn = std::string (GLSLDecompiler::*)(Operation);
using OperationDecompilersArray =
std::array<OperationDecompilerFn, static_cast<std::size_t>(OperationCode::Amount)>;
void DeclareVertex() {
if (stage != ShaderStage::Vertex)
return;
bool clip_distances_declared = false;
code.AddLine("out gl_PerVertex {");
++code.scope;
code.AddLine("vec4 gl_Position;");
for (const auto o : ir.GetOutputAttributes()) {
if (o == Attribute::Index::PointSize)
code.AddLine("float gl_PointSize;");
if (!clip_distances_declared && (o == Attribute::Index::ClipDistances0123 ||
o == Attribute::Index::ClipDistances4567)) {
code.AddLine("float gl_ClipDistance[];");
clip_distances_declared = true;
}
}
--code.scope;
code.AddLine("};");
code.AddNewLine();
}
void DeclareRegisters() {
const auto& registers = ir.GetRegisters();
for (const u32 gpr : registers) {
code.AddLine("float " + GetRegister(gpr) + " = 0;");
}
if (!registers.empty())
code.AddNewLine();
}
void DeclarePredicates() {
const auto& predicates = ir.GetPredicates();
for (const auto pred : predicates) {
code.AddLine("bool " + GetPredicate(pred) + " = false;");
}
if (!predicates.empty())
code.AddNewLine();
}
void DeclareLocalMemory() {
if (const u64 local_memory_size = header.GetLocalMemorySize(); local_memory_size > 0) {
const auto element_count = Common::AlignUp(local_memory_size, 4) / 4;
code.AddLine("float " + GetLocalMemory() + '[' + std::to_string(element_count) + "];");
code.AddNewLine();
}
}
void DeclareInternalFlags() {
for (u32 flag = 0; flag < static_cast<u32>(InternalFlag::Amount); flag++) {
const InternalFlag flag_code = static_cast<InternalFlag>(flag);
code.AddLine("bool " + GetInternalFlag(flag_code) + " = false;");
}
code.AddNewLine();
}
std::string GetInputFlags(const IpaMode& input_mode) {
const IpaSampleMode sample_mode = input_mode.sampling_mode;
const IpaInterpMode interp_mode = input_mode.interpolation_mode;
std::string out;
switch (interp_mode) {
case IpaInterpMode::Flat:
out += "flat ";
break;
case IpaInterpMode::Linear:
out += "noperspective ";
break;
case IpaInterpMode::Perspective:
// Default, Smooth
break;
default:
UNIMPLEMENTED_MSG("Unhandled IPA interp mode: {}", static_cast<u32>(interp_mode));
}
switch (sample_mode) {
case IpaSampleMode::Centroid:
// It can be implemented with the "centroid " keyword in GLSL
UNIMPLEMENTED_MSG("Unimplemented IPA sampler mode centroid");
break;
case IpaSampleMode::Default:
// Default, n/a
break;
default:
UNIMPLEMENTED_MSG("Unimplemented IPA sampler mode: {}", static_cast<u32>(sample_mode));
}
return out;
}
void DeclareInputAttributes() {
const auto& attributes = ir.GetInputAttributes();
for (const auto element : attributes) {
const Attribute::Index index = element.first;
const IpaMode& input_mode = *element.second.begin();
if (index < Attribute::Index::Attribute_0 || index > Attribute::Index::Attribute_31) {
// Skip when it's not a generic attribute
continue;
}
ASSERT(element.second.size() > 0);
// UNIMPLEMENTED_IF_MSG(element.second.size() > 1,
// "Multiple input flag modes are not supported in GLSL");
// TODO(bunnei): Use proper number of elements for these
u32 idx = static_cast<u32>(index) - static_cast<u32>(Attribute::Index::Attribute_0);
if (stage != ShaderStage::Vertex) {
// If inputs are varyings, add an offset
idx += GENERIC_VARYING_START_LOCATION;
}
std::string attr = GetInputAttribute(index);
if (stage == ShaderStage::Geometry) {
attr = "gs_" + attr + "[]";
}
code.AddLine("layout (location = " + std::to_string(idx) + ") " +
GetInputFlags(input_mode) + "in vec4 " + attr + ';');
}
if (!attributes.empty())
code.AddNewLine();
}
void DeclareOutputAttributes() {
const auto& attributes = ir.GetOutputAttributes();
for (const auto index : attributes) {
if (index < Attribute::Index::Attribute_0 || index > Attribute::Index::Attribute_31) {
// Skip when it's not a generic attribute
continue;
}
// TODO(bunnei): Use proper number of elements for these
const auto idx = static_cast<u32>(index) -
static_cast<u32>(Attribute::Index::Attribute_0) +
GENERIC_VARYING_START_LOCATION;
code.AddLine("layout (location = " + std::to_string(idx) + ") out vec4 " +
GetOutputAttribute(index) + ';');
}
if (!attributes.empty())
code.AddNewLine();
}
void DeclareConstantBuffers() {
for (const auto& entry : ir.GetConstantBuffers()) {
const auto [index, size] = entry;
code.AddLine("layout (std140) uniform " + GetConstBufferBlock(index) + " {");
code.AddLine(" vec4 " + GetConstBuffer(index) + "[MAX_CONSTBUFFER_ELEMENTS];");
code.AddLine("};");
code.AddNewLine();
}
}
void DeclareSamplers() {
const auto& samplers = ir.GetSamplers();
for (const auto& sampler : samplers) {
std::string sampler_type = [&]() {
switch (sampler.GetType()) {
case Tegra::Shader::TextureType::Texture1D:
return "sampler1D";
case Tegra::Shader::TextureType::Texture2D:
return "sampler2D";
case Tegra::Shader::TextureType::Texture3D:
return "sampler3D";
case Tegra::Shader::TextureType::TextureCube:
return "samplerCube";
default:
UNREACHABLE();
return "sampler2D";
}
}();
if (sampler.IsArray())
sampler_type += "Array";
if (sampler.IsShadow())
sampler_type += "Shadow";
code.AddLine("uniform " + sampler_type + ' ' + GetSampler(sampler) + ';');
}
if (!samplers.empty())
code.AddNewLine();
}
void VisitBasicBlock(const BasicBlock& bb) {
for (const Node node : bb) {
if (const std::string expr = Visit(node); !expr.empty()) {
code.AddLine(expr);
}
}
}
std::string Visit(Node node) {
if (const auto operation = std::get_if<OperationNode>(node)) {
const auto operation_index = static_cast<std::size_t>(operation->GetCode());
const auto decompiler = operation_decompilers[operation_index];
if (decompiler == nullptr) {
UNREACHABLE_MSG("Operation decompiler {} not defined", operation_index);
}
return (this->*decompiler)(*operation);
} else if (const auto gpr = std::get_if<GprNode>(node)) {
const u32 index = gpr->GetIndex();
if (index == RZ) {
return "0";
}
return GetRegister(index);
} else if (const auto immediate = std::get_if<ImmediateNode>(node)) {
const u32 value = immediate->GetValue();
if (value < 10) {
// For eyecandy avoid using hex numbers on single digits
return fmt::format("utof({}u)", immediate->GetValue());
}
return fmt::format("utof(0x{:x}u)", immediate->GetValue());
} else if (const auto predicate = std::get_if<PredicateNode>(node)) {
const auto value = [&]() -> std::string {
switch (const auto index = predicate->GetIndex(); index) {
case Tegra::Shader::Pred::UnusedIndex:
return "true";
case Tegra::Shader::Pred::NeverExecute:
return "false";
default:
return GetPredicate(index);
}
}();
if (predicate->IsNegated()) {
return "!(" + value + ')';
}
return value;
} else if (const auto abuf = std::get_if<AbufNode>(node)) {
const auto attribute = abuf->GetIndex();
const auto element = abuf->GetElement();
switch (attribute) {
case Attribute::Index::Position:
return element == 3 ? "1.0f" : "gl_FragCoord" + GetSwizzle(element);
case Attribute::Index::PointCoord:
switch (element) {
case 0:
return "gl_PointCoord.x";
case 1:
return "gl_PointCoord.y";
case 2:
case 3:
return "0";
}
UNREACHABLE();
return "0";
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 == ShaderStage::Vertex);
switch (element) {
case 2:
// Config pack's first value is instance_id.
return "uintBitsToFloat(config_pack[0])";
case 3:
return "uintBitsToFloat(gl_VertexID)";
}
UNIMPLEMENTED_MSG("Unmanaged TessCoordInstanceIDVertexID element={}", element);
return "0";
case Attribute::Index::FrontFacing:
// TODO(Subv): Find out what the values are for the other elements.
ASSERT(stage == ShaderStage::Fragment);
switch (element) {
case 3:
return "itof(gl_FrontFacing ? -1 : 0)";
}
UNIMPLEMENTED_MSG("Unmanaged FrontFacing element={}", element);
return "0";
default:
if (attribute >= Attribute::Index::Attribute_0 &&
attribute <= Attribute::Index::Attribute_31) {
return GetInputAttribute(attribute) + GetSwizzle(abuf->GetElement());
}
break;
}
UNIMPLEMENTED_MSG("Unhandled input attribute: {}", static_cast<u32>(attribute));
} else if (const auto cbuf = std::get_if<CbufNode>(node)) {
const Node offset = cbuf->GetOffset();
if (const auto immediate = std::get_if<ImmediateNode>(offset)) {
// Direct access
const u32 offset_imm = immediate->GetValue();
return fmt::format("{}[{}][{}]", GetConstBuffer(cbuf->GetIndex()), offset_imm / 4,
offset_imm % 4);
} else if (std::holds_alternative<OperationNode>(*offset)) {
// Indirect access
const std::string final_offset = code.GenerateTemporal();
code.AddLine("uint " + final_offset + " = (ftou(" + Visit(offset) + ") / 4) & " +
std::to_string(MAX_CONSTBUFFER_ELEMENTS - 1) + ';');
return fmt::format("{}[{} / 4][{} % 4]", GetConstBuffer(cbuf->GetIndex()),
final_offset, final_offset);
} else {
UNREACHABLE_MSG("Unmanaged offset node type");
}
} else if (const auto lmem = std::get_if<LmemNode>(node)) {
return fmt::format("{}[ftou({}) / 4]", GetLocalMemory(), Visit(lmem->GetAddress()));
} else if (const auto internal_flag = std::get_if<InternalFlagNode>(node)) {
return GetInternalFlag(internal_flag->GetFlag());
} else if (const auto conditional = std::get_if<ConditionalNode>(node)) {
// It's invalid to call conditional on nested nodes, use an operation instead
code.AddLine("if (" + Visit(conditional->GetCondition()) + ") {");
++code.scope;
VisitBasicBlock(conditional->GetCode());
--code.scope;
code.AddLine('}');
return {};
} else if (const auto comment = std::get_if<CommentNode>(node)) {
return "// " + comment->GetText();
}
UNREACHABLE();
return {};
}
std::string ApplyPrecise(Operation operation, const std::string& value) {
if (!IsPrecise(operation)) {
return value;
}
// There's a bug in NVidia's proprietary drivers that makes precise fail on fragment shaders
const std::string precise = stage != ShaderStage::Fragment ? "precise " : "";
const std::string temporal = code.GenerateTemporal();
code.AddLine(precise + "float " + temporal + " = " + value + ';');
return temporal;
}
std::string VisitOperand(Operation operation, std::size_t operand_index) {
const auto& operand = operation[operand_index];
const bool parent_precise = IsPrecise(operation);
const bool child_precise = IsPrecise(operand);
const bool child_trivial = !std::holds_alternative<OperationNode>(*operand);
if (!parent_precise || child_precise || child_trivial) {
return Visit(operand);
}
const std::string temporal = code.GenerateTemporal();
code.AddLine("float " + temporal + " = " + Visit(operand) + ';');
return temporal;
}
std::string VisitOperand(Operation operation, std::size_t operand_index, Type type) {
std::string value = VisitOperand(operation, operand_index);
switch (type) {
case Type::Bool:
case Type::Float:
return value;
case Type::Int:
return "ftoi(" + value + ')';
case Type::Uint:
return "ftou(" + value + ')';
case Type::HalfFloat:
if (!std::holds_alternative<MetaHalfArithmetic>(operation.GetMeta())) {
value = "toHalf2(" + value + ')';
}
const auto& half_meta = std::get<MetaHalfArithmetic>(operation.GetMeta());
switch (half_meta.types.at(operand_index)) {
case Tegra::Shader::HalfType::H0_H1:
return "toHalf2(" + value + ')';
case Tegra::Shader::HalfType::F32:
return "vec2(" + value + ')';
case Tegra::Shader::HalfType::H0_H0:
return "vec2(toHalf2(" + value + ")[0])";
case Tegra::Shader::HalfType::H1_H1:
return "vec2(toHalf2(" + value + ")[1])";
}
}
UNREACHABLE();
return value;
}
std::string BitwiseCastResult(std::string value, Type type, bool needs_parenthesis = false) {
switch (type) {
case Type::Bool:
case Type::Float:
if (needs_parenthesis) {
return '(' + value + ')';
}
return value;
case Type::Int:
return "itof(" + value + ')';
case Type::Uint:
return "utof(" + value + ')';
case Type::HalfFloat:
return "fromHalf2(" + value + ')';
}
UNREACHABLE();
return value;
}
std::string GenerateUnary(Operation operation, const std::string& func, Type result_type,
Type type_a, bool needs_parenthesis = true) {
return ApplyPrecise(operation,
BitwiseCastResult(func + '(' + VisitOperand(operation, 0, type_a) + ')',
result_type, needs_parenthesis));
}
std::string GenerateBinaryInfix(Operation operation, const std::string& func, Type result_type,
Type type_a, Type type_b) {
const std::string op_a = VisitOperand(operation, 0, type_a);
const std::string op_b = VisitOperand(operation, 1, type_b);
return ApplyPrecise(
operation, BitwiseCastResult('(' + op_a + ' ' + func + ' ' + op_b + ')', result_type));
}
std::string GenerateBinaryCall(Operation operation, const std::string& func, Type result_type,
Type type_a, Type type_b) {
const std::string op_a = VisitOperand(operation, 0, type_a);
const std::string op_b = VisitOperand(operation, 1, type_b);
return ApplyPrecise(operation,
BitwiseCastResult(func + '(' + op_a + ", " + op_b + ')', result_type));
}
std::string GenerateTernary(Operation operation, const std::string& func, Type result_type,
Type type_a, Type type_b, Type type_c) {
const std::string op_a = VisitOperand(operation, 0, type_a);
const std::string op_b = VisitOperand(operation, 1, type_b);
const std::string op_c = VisitOperand(operation, 2, type_c);
return ApplyPrecise(
operation,
BitwiseCastResult(func + '(' + op_a + ", " + op_b + ", " + op_c + ')', result_type));
}
std::string GenerateQuaternary(Operation operation, const std::string& func, Type result_type,
Type type_a, Type type_b, Type type_c, Type type_d) {
const std::string op_a = VisitOperand(operation, 0, type_a);
const std::string op_b = VisitOperand(operation, 1, type_b);
const std::string op_c = VisitOperand(operation, 2, type_c);
const std::string op_d = VisitOperand(operation, 3, type_d);
return ApplyPrecise(operation, BitwiseCastResult(func + '(' + op_a + ", " + op_b + ", " +
op_c + ", " + op_d + ')',
result_type));
}
std::string GenerateTexture(Operation operation, const std::string& func,
std::string extra_cast(std::string) = nullptr) {
constexpr std::array<const char*, 4> coord_constructors = {"float", "vec2", "vec3", "vec4"};
const auto& meta = std::get<MetaTexture>(operation.GetMeta());
const auto count = static_cast<u32>(operation.GetOperandsCount());
std::string expr = func;
expr += '(';
expr += GetSampler(meta.sampler);
expr += ", ";
expr += coord_constructors[meta.coords_count - 1];
expr += '(';
for (u32 i = 0; i < count; ++i) {
const bool is_extra = i >= meta.coords_count;
const bool is_array = i == meta.array_index;
std::string operand = Visit(operation[i]);
if (is_extra && extra_cast != nullptr) {
operand = extra_cast(operand);
}
if (is_array) {
ASSERT(!is_extra);
operand = "float(ftoi(" + operand + "))";
}
expr += operand;
if (i + 1 == meta.coords_count) {
expr += ')';
}
if (i + 1 < count) {
expr += ", ";
}
}
expr += ')';
return expr;
}
std::string Assign(Operation operation) {
const Node dest = operation[0];
const Node src = operation[1];
std::string target;
if (const auto gpr = std::get_if<GprNode>(dest)) {
if (gpr->GetIndex() == RZ) {
// Writing to RZ is a no op
return {};
}
target = GetRegister(gpr->GetIndex());
} else if (const auto abuf = std::get_if<AbufNode>(dest)) {
target = [&]() -> std::string {
switch (const auto attribute = abuf->GetIndex(); abuf->GetIndex()) {
case Attribute::Index::Position:
return "position" + GetSwizzle(abuf->GetElement());
case Attribute::Index::PointSize:
return "gl_PointSize";
case Attribute::Index::ClipDistances0123:
return "gl_ClipDistance[" + std::to_string(abuf->GetElement()) + ']';
case Attribute::Index::ClipDistances4567:
return "gl_ClipDistance[" + std::to_string(abuf->GetElement() + 4) + ']';
default:
if (attribute >= Attribute::Index::Attribute_0 &&
attribute <= Attribute::Index::Attribute_31) {
return GetOutputAttribute(attribute) + GetSwizzle(abuf->GetElement());
}
UNIMPLEMENTED_MSG("Unhandled output attribute: {}",
static_cast<u32>(attribute));
return "0";
}
}();
} else if (const auto lmem = std::get_if<LmemNode>(dest)) {
target = GetLocalMemory() + "[ftou(" + Visit(lmem->GetAddress()) + ") / 4]";
} else {
UNREACHABLE_MSG("Assign called without a proper target");
}
code.AddLine(target + " = " + Visit(src) + ';');
return {};
}
std::string AssignComposite(Operation operation) {
const auto& meta = std::get<MetaComponents>(operation.GetMeta());
const std::string composite = code.GenerateTemporal();
code.AddLine("vec4 " + composite + " = " + Visit(operation[0]) + ';');
constexpr u32 composite_size = 4;
for (u32 i = 0; i < composite_size; ++i) {
const auto gpr = std::get<GprNode>(*operation[i + 1]).GetIndex();
if (gpr == RZ) {
continue;
}
code.AddLine(GetRegister(gpr) + " = " + composite +
GetSwizzle(meta.GetSourceComponent(i)) + ';');
}
return {};
}
std::string Composite(Operation operation) {
std::string value = "vec4(";
for (std::size_t i = 0; i < 4; ++i) {
value += Visit(operation[i]);
if (i < 3)
value += ", ";
}
value += ')';
return value;
}
template <Type type>
std::string Add(Operation operation) {
return GenerateBinaryInfix(operation, "+", type, type, type);
}
template <Type type>
std::string Mul(Operation operation) {
return GenerateBinaryInfix(operation, "*", type, type, type);
}
template <Type type>
std::string Div(Operation operation) {
return GenerateBinaryInfix(operation, "/", type, type, type);
}
template <Type type>
std::string Fma(Operation operation) {
return GenerateTernary(operation, "fma", type, type, type, type);
}
template <Type type>
std::string Negate(Operation operation) {
return GenerateUnary(operation, "-", type, type, true);
}
template <Type type>
std::string Absolute(Operation operation) {
return GenerateUnary(operation, "abs", type, type, false);
}
std::string FClamp(Operation operation) {
return GenerateTernary(operation, "clamp", Type::Float, Type::Float, Type::Float,
Type::Float);
}
template <Type type>
std::string Min(Operation operation) {
return GenerateBinaryCall(operation, "min", type, type, type);
}
template <Type type>
std::string Max(Operation operation) {
return GenerateBinaryCall(operation, "max", type, type, type);
}
std::string Select(Operation operation) {
const std::string condition = Visit(operation[0]);
const std::string true_case = Visit(operation[1]);
const std::string false_case = Visit(operation[2]);
return ApplyPrecise(operation,
'(' + condition + " ? " + true_case + " : " + false_case + ')');
}
std::string FCos(Operation operation) {
return GenerateUnary(operation, "cos", Type::Float, Type::Float, false);
}
std::string FSin(Operation operation) {
return GenerateUnary(operation, "sin", Type::Float, Type::Float, false);
}
std::string FExp2(Operation operation) {
return GenerateUnary(operation, "exp2", Type::Float, Type::Float, false);
}
std::string FLog2(Operation operation) {
return GenerateUnary(operation, "log2", Type::Float, Type::Float, false);
}
std::string FInverseSqrt(Operation operation) {
return GenerateUnary(operation, "inversesqrt", Type::Float, Type::Float, false);
}
std::string FSqrt(Operation operation) {
return GenerateUnary(operation, "sqrt", Type::Float, Type::Float, false);
}
std::string FRoundEven(Operation operation) {
return GenerateUnary(operation, "roundEven", Type::Float, Type::Float, false);
}
std::string FFloor(Operation operation) {
return GenerateUnary(operation, "floor", Type::Float, Type::Float, false);
}
std::string FCeil(Operation operation) {
return GenerateUnary(operation, "ceil", Type::Float, Type::Float, false);
}
std::string FTrunc(Operation operation) {
return GenerateUnary(operation, "trunc", Type::Float, Type::Float, false);
}
template <Type type>
std::string FCastInteger(Operation operation) {
return GenerateUnary(operation, "float", Type::Float, type, false);
}
std::string ICastFloat(Operation operation) {
return GenerateUnary(operation, "int", Type::Int, Type::Float, false);
}
std::string ICastUnsigned(Operation operation) {
return GenerateUnary(operation, "int", Type::Int, Type::Uint, false);
}
template <Type type>
std::string LogicalShiftLeft(Operation operation) {
return GenerateBinaryInfix(operation, "<<", type, type, Type::Uint);
}
std::string ILogicalShiftRight(Operation operation) {
const std::string op_a = VisitOperand(operation, 0, Type::Uint);
const std::string op_b = VisitOperand(operation, 1, Type::Uint);
return ApplyPrecise(operation,
BitwiseCastResult("int(" + op_a + " >> " + op_b + ')', Type::Int));
}
std::string IArithmeticShiftRight(Operation operation) {
return GenerateBinaryInfix(operation, ">>", Type::Int, Type::Int, Type::Uint);
}
template <Type type>
std::string BitwiseAnd(Operation operation) {
return GenerateBinaryInfix(operation, "&", type, type, type);
}
template <Type type>
std::string BitwiseOr(Operation operation) {
return GenerateBinaryInfix(operation, "|", type, type, type);
}
template <Type type>
std::string BitwiseXor(Operation operation) {
return GenerateBinaryInfix(operation, "^", type, type, type);
}
template <Type type>
std::string BitwiseNot(Operation operation) {
return GenerateUnary(operation, "~", type, type, false);
}
std::string UCastFloat(Operation operation) {
return GenerateUnary(operation, "uint", Type::Uint, Type::Float, false);
}
std::string UCastSigned(Operation operation) {
return GenerateUnary(operation, "uint", Type::Uint, Type::Int, false);
}
std::string UShiftRight(Operation operation) {
return GenerateBinaryInfix(operation, ">>", Type::Uint, Type::Uint, Type::Uint);
}
template <Type type>
std::string BitfieldInsert(Operation operation) {
return GenerateQuaternary(operation, "bitfieldInsert", type, type, type, Type::Int,
Type::Int);
}
template <Type type>
std::string BitCount(Operation operation) {
return GenerateUnary(operation, "bitCount", type, type, false);
}
std::string HNegate(Operation operation) {
const auto GetNegate = [&](std::size_t index) -> std::string {
return VisitOperand(operation, index, Type::Bool) + " ? -1 : 1";
};
const std::string value = '(' + VisitOperand(operation, 0, Type::HalfFloat) + " * vec2(" +
GetNegate(1) + ", " + GetNegate(2) + "))";
return BitwiseCastResult(value, Type::HalfFloat);
}
std::string HMergeF32(Operation operation) {
return "float(toHalf2(" + Visit(operation[0]) + ")[0])";
}
std::string HMergeH0(Operation operation) {
return "fromHalf2(vec2(toHalf2(" + Visit(operation[0]) + ")[1], toHalf2(" +
Visit(operation[1]) + ")[0]))";
}
std::string HMergeH1(Operation operation) {
return "fromHalf2(vec2(toHalf2(" + Visit(operation[0]) + ")[0], toHalf2(" +
Visit(operation[1]) + ")[1]))";
}
template <Type type>
std::string LogicalLessThan(Operation operation) {
return GenerateBinaryInfix(operation, "<", Type::Bool, type, type);
}
template <Type type>
std::string LogicalEqual(Operation operation) {
return GenerateBinaryInfix(operation, "==", Type::Bool, type, type);
}
template <Type type>
std::string LogicalLessEqual(Operation operation) {
return GenerateBinaryInfix(operation, "<=", Type::Bool, type, type);
}
template <Type type>
std::string LogicalGreaterThan(Operation operation) {
return GenerateBinaryInfix(operation, ">", Type::Bool, type, type);
}
template <Type type>
std::string LogicalNotEqual(Operation operation) {
return GenerateBinaryInfix(operation, "!=", Type::Bool, type, type);
}
template <Type type>
std::string LogicalGreaterEqual(Operation operation) {
return GenerateBinaryInfix(operation, ">=", Type::Bool, type, type);
}
std::string LogicalFIsNan(Operation operation) {
return GenerateUnary(operation, "isnan", Type::Bool, Type::Float, false);
}
std::string LogicalAssign(Operation operation) {
const Node dest = operation[0];
const Node src = operation[1];
std::string target;
if (const auto pred = std::get_if<PredicateNode>(dest)) {
ASSERT_MSG(!pred->IsNegated(), "Negating logical assignment");
const auto index = pred->GetIndex();
switch (index) {
case Tegra::Shader::Pred::NeverExecute:
case Tegra::Shader::Pred::UnusedIndex:
// Writing to these predicates is a no-op
return {};
}
target = GetPredicate(index);
} else if (const auto flag = std::get_if<InternalFlagNode>(dest)) {
target = GetInternalFlag(flag->GetFlag());
}
code.AddLine(target + " = " + Visit(src) + ';');
return {};
}
std::string LogicalAnd(Operation operation) {
return GenerateBinaryInfix(operation, "&&", Type::Bool, Type::Bool, Type::Bool);
}
std::string LogicalOr(Operation operation) {
return GenerateBinaryInfix(operation, "||", Type::Bool, Type::Bool, Type::Bool);
}
std::string LogicalXor(Operation operation) {
return GenerateBinaryInfix(operation, "^^", Type::Bool, Type::Bool, Type::Bool);
}
std::string LogicalNegate(Operation operation) {
return GenerateUnary(operation, "!", Type::Bool, Type::Bool, false);
}
std::string LogicalHComparison(Operation operation, const std::string& func) {
const auto& meta = std::get<MetaHalfArithmetic>(operation.GetMeta());
const std::string op_a = VisitOperand(operation, 0, Type::HalfFloat);
const std::string op_b = VisitOperand(operation, 1, Type::HalfFloat);
std::string value = meta.and_comparison ? "all" : "any";
value += '(' + func + '(' + op_a + ", " + op_b + "))";
return value;
}
std::string LogicalHLessThan(Operation operation) {
return LogicalHComparison(operation, "lessThan");
}
std::string LogicalHEqual(Operation operation) {
return LogicalHComparison(operation, "equal");
}
std::string LogicalHLessEqual(Operation operation) {
return LogicalHComparison(operation, "lessThanEqual");
}
std::string LogicalHGreaterThan(Operation operation) {
return LogicalHComparison(operation, "greaterThan");
}
std::string LogicalHNotEqual(Operation operation) {
return LogicalHComparison(operation, "notEqual");
}
std::string LogicalHGreaterEqual(Operation operation) {
return LogicalHComparison(operation, "greaterThanEqual");
}
std::string F4Texture(Operation operation) {
std::string expr = GenerateTexture(operation, "texture");
if (std::get<MetaTexture>(operation.GetMeta()).sampler.IsShadow()) {
expr = "vec4(" + expr + ')';
}
return expr;
}
std::string F4TextureLod(Operation operation) {
std::string expr = GenerateTexture(operation, "textureLod");
if (std::get<MetaTexture>(operation.GetMeta()).sampler.IsShadow()) {
expr = "vec4(" + expr + ')';
}
return expr;
}
std::string F4TextureGather(Operation operation) {
const bool is_shadow = std::get<MetaTexture>(operation.GetMeta()).sampler.IsShadow();
if (is_shadow) {
return GenerateTexture(operation, "textureGather",
[](std::string ref_z) { return ref_z; });
} else {
return GenerateTexture(operation, "textureGather",
[](std::string comp) { return "ftoi(" + comp + ')'; });
}
}
std::string F4TextureQueryDimensions(Operation operation) {
const auto& meta = std::get<MetaTexture>(operation.GetMeta());
const std::string sampler = GetSampler(meta.sampler);
const std::string lod = VisitOperand(operation, 0, Type::Int);
const std::string sizes = code.GenerateTemporal();
code.AddLine("ivec2 " + sizes + " = textureSize(" + sampler + ", " + lod + ");");
const std::string mip_level = "textureQueryLevels(" + sampler + ')';
return "itof(ivec4(" + sizes + ", 0, " + mip_level + "))";
}
std::string F4TextureQueryLod(Operation operation) {
const std::string tmp = code.GenerateTemporal();
code.AddLine("vec2 " + tmp + " = " + GenerateTexture(operation, "textureQueryLod") +
" * vec2(256);");
return "vec4(itof(int(" + tmp + ".y)), utof(uint(" + tmp + ".x)), 0, 0)";
}
std::string F4TexelFetch(Operation operation) {
constexpr std::array<const char*, 4> constructors = {"int", "ivec2", "ivec3", "ivec4"};
const auto& meta = std::get<MetaTexture>(operation.GetMeta());
const auto count = static_cast<u32>(operation.GetOperandsCount());
std::string expr = "texelFetch(";
expr += GetSampler(meta.sampler);
expr += ", ";
expr += constructors[meta.coords_count - 1];
expr += '(';
for (u32 i = 0; i < count; ++i) {
expr += VisitOperand(operation, i, Type::Int);
expr += ", ";
if (i + 1 == meta.coords_count) {
expr += ')';
}
if (i + 1 < count) {
expr += ", ";
}
}
expr += ')';
return expr;
}
std::string Ipa(Operation operation) {
const auto& attribute = operation[0];
// TODO(Rodrigo): Special IPA attribute interactions
return Visit(attribute);
}
std::string Bra(Operation operation) {
const auto target = std::get<ImmediateNode>(*operation[0]);
code.AddLine(fmt::format("jmp_to = 0x{:x}u;", target.GetValue()));
code.AddLine("break;");
return {};
}
std::string PushFlowStack(Operation operation) {
const auto target = std::get<ImmediateNode>(*operation[0]);
code.AddLine(fmt::format("flow_stack[flow_stack_top] = 0x{:x}u;", target.GetValue()));
code.AddLine("flow_stack_top++;");
return {};
}
std::string PopFlowStack(Operation operation) {
code.AddLine("flow_stack_top--;");
code.AddLine("jmp_to = flow_stack[flow_stack_top];");
code.AddLine("break;");
return {};
}
std::string Exit(Operation operation) {
if (stage != ShaderStage::Fragment) {
code.AddLine("return;");
return {};
}
const auto& used_registers = ir.GetRegisters();
const auto SafeGetRegister = [&](u32 reg) -> std::string {
// TODO(Rodrigo): Replace with contains once C++20 releases
if (used_registers.find(reg) != used_registers.end()) {
return GetRegister(reg);
}
return "0.0f";
};
UNIMPLEMENTED_IF_MSG(header.ps.omap.sample_mask != 0, "Sample mask write is unimplemented");
code.AddLine("if (alpha_test[0] != 0) {");
++code.scope;
// We start on the register containing the alpha value in the first RT.
u32 current_reg = 3;
for (u32 render_target = 0; render_target < Maxwell::NumRenderTargets; ++render_target) {
// TODO(Blinkhawk): verify the behavior of alpha testing on hardware when
// multiple render targets are used.
if (header.ps.IsColorComponentOutputEnabled(render_target, 0) ||
header.ps.IsColorComponentOutputEnabled(render_target, 1) ||
header.ps.IsColorComponentOutputEnabled(render_target, 2) ||
header.ps.IsColorComponentOutputEnabled(render_target, 3)) {
code.AddLine(
fmt::format("if (!AlphaFunc({})) discard;", SafeGetRegister(current_reg)));
current_reg += 4;
}
}
--code.scope;
code.AddLine('}');
// Write the color outputs using the data in the shader registers, disabled
// rendertargets/components are skipped in the register assignment.
current_reg = 0;
for (u32 render_target = 0; render_target < Maxwell::NumRenderTargets; ++render_target) {
// TODO(Subv): Figure out how dual-source blending is configured in the Switch.
for (u32 component = 0; component < 4; ++component) {
if (header.ps.IsColorComponentOutputEnabled(render_target, component)) {
code.AddLine(fmt::format("FragColor{}[{}] = {};", render_target, component,
SafeGetRegister(current_reg)));
++current_reg;
}
}
}
if (header.ps.omap.depth) {
// The depth output is always 2 registers after the last color output, and current_reg
// already contains one past the last color register.
code.AddLine("gl_FragDepth = " + SafeGetRegister(current_reg + 1) + ';');
}
code.AddLine("return;");
return {};
}
std::string Kil(Operation operation) {
// Enclose "discard" in a conditional, so that GLSL compilation does not complain
// about unexecuted instructions that may follow this.
code.AddLine("if (true) {");
++code.scope;
code.AddLine("discard;");
--code.scope;
code.AddLine("}");
return {};
}
std::string YNegate(Operation operation) {
// Config pack's third value is Y_NEGATE's state.
return "uintBitsToFloat(config_pack[2])";
}
static constexpr OperationDecompilersArray operation_decompilers = {
&Assign,
&AssignComposite,
&Composite,
&Select,
&Add<Type::Float>,
&Mul<Type::Float>,
&Div<Type::Float>,
&Fma<Type::Float>,
&Negate<Type::Float>,
&Absolute<Type::Float>,
&FClamp,
&Min<Type::Float>,
&Max<Type::Float>,
&FCos,
&FSin,
&FExp2,
&FLog2,
&FInverseSqrt,
&FSqrt,
&FRoundEven,
&FFloor,
&FCeil,
&FTrunc,
&FCastInteger<Type::Int>,
&FCastInteger<Type::Uint>,
&Add<Type::Int>,
&Mul<Type::Int>,
&Div<Type::Int>,
&Negate<Type::Int>,
&Absolute<Type::Int>,
&Min<Type::Int>,
&Max<Type::Int>,
&ICastFloat,
&ICastUnsigned,
&LogicalShiftLeft<Type::Int>,
&ILogicalShiftRight,
&IArithmeticShiftRight,
&BitwiseAnd<Type::Int>,
&BitwiseOr<Type::Int>,
&BitwiseXor<Type::Int>,
&BitwiseNot<Type::Int>,
&BitfieldInsert<Type::Int>,
&BitCount<Type::Int>,
&Add<Type::Uint>,
&Mul<Type::Uint>,
&Div<Type::Uint>,
&Min<Type::Uint>,
&Max<Type::Uint>,
&UCastFloat,
&UCastSigned,
&LogicalShiftLeft<Type::Uint>,
&UShiftRight,
&UShiftRight,
&BitwiseAnd<Type::Uint>,
&BitwiseOr<Type::Uint>,
&BitwiseXor<Type::Uint>,
&BitwiseNot<Type::Uint>,
&BitfieldInsert<Type::Uint>,
&BitCount<Type::Uint>,
&Add<Type::HalfFloat>,
&Mul<Type::HalfFloat>,
&Fma<Type::HalfFloat>,
&Absolute<Type::HalfFloat>,
&HNegate,
&HMergeF32,
&HMergeH0,
&HMergeH1,
&LogicalAssign,
&LogicalAnd,
&LogicalOr,
&LogicalXor,
&LogicalNegate,
&LogicalLessThan<Type::Float>,
&LogicalEqual<Type::Float>,
&LogicalLessEqual<Type::Float>,
&LogicalGreaterThan<Type::Float>,
&LogicalNotEqual<Type::Float>,
&LogicalGreaterEqual<Type::Float>,
&LogicalFIsNan,
&LogicalLessThan<Type::Int>,
&LogicalEqual<Type::Int>,
&LogicalLessEqual<Type::Int>,
&LogicalGreaterThan<Type::Int>,
&LogicalNotEqual<Type::Int>,
&LogicalGreaterEqual<Type::Int>,
&LogicalLessThan<Type::Uint>,
&LogicalEqual<Type::Uint>,
&LogicalLessEqual<Type::Uint>,
&LogicalGreaterThan<Type::Uint>,
&LogicalNotEqual<Type::Uint>,
&LogicalGreaterEqual<Type::Uint>,
&LogicalHLessThan,
&LogicalHEqual,
&LogicalHLessEqual,
&LogicalHGreaterThan,
&LogicalHNotEqual,
&LogicalHGreaterEqual,
&F4Texture,
&F4TextureLod,
&F4TextureGather,
&F4TextureQueryDimensions,
&F4TextureQueryLod,
&F4TexelFetch,
&Ipa,
&Bra,
&PushFlowStack, // Ssy
&PushFlowStack, // Brk
&PopFlowStack, // Sync
&PopFlowStack, // Brk
&Exit,
&Kil,
&YNegate,
};
std::string GetRegister(u32 index) const {
return GetDeclarationWithSuffix(index, "gpr");
}
std::string GetPredicate(Tegra::Shader::Pred pred) const {
return GetDeclarationWithSuffix(static_cast<u32>(pred), "pred");
}
std::string GetInputAttribute(Attribute::Index attribute) const {
const auto index{static_cast<u32>(attribute) -
static_cast<u32>(Attribute::Index::Attribute_0)};
return GetDeclarationWithSuffix(index, "input_attr");
}
std::string GetOutputAttribute(Attribute::Index attribute) const {
const auto index{static_cast<u32>(attribute) -
static_cast<u32>(Attribute::Index::Attribute_0)};
return GetDeclarationWithSuffix(index, "output_attr");
}
std::string GetConstBuffer(u32 index) const {
return GetDeclarationWithSuffix(index, "cbuf");
}
std::string GetConstBufferBlock(u32 index) const {
return GetDeclarationWithSuffix(index, "cbuf_block");
}
std::string GetLocalMemory() const {
return "lmem_" + suffix;
}
std::string GetInternalFlag(InternalFlag flag) const {
constexpr std::array<const char*, 4> InternalFlagNames = {"zero_flag", "sign_flag",
"carry_flag", "overflow_flag"};
const auto index = static_cast<u32>(flag);
ASSERT(index < static_cast<u32>(InternalFlag::Amount));
return std::string(InternalFlagNames[index]) + '_' + suffix;
}
std::string GetSampler(const Sampler& sampler) const {
return GetDeclarationWithSuffix(static_cast<u32>(sampler.GetIndex()), "sampler");
}
std::string GetDeclarationWithSuffix(u32 index, const std::string& name) const {
return name + '_' + std::to_string(index) + '_' + suffix;
}
const ShaderIR& ir;
const ShaderStage stage;
const std::string suffix;
const Header header;
ShaderWriter code;
};
std::string GetCommonDeclarations() {
return "#define MAX_CONSTBUFFER_ELEMENTS " + std::to_string(MAX_CONSTBUFFER_ELEMENTS) +
"\n"
"#define ftoi floatBitsToInt\n"
"#define ftou floatBitsToUint\n"
"#define itof intBitsToFloat\n"
"#define utof uintBitsToFloat\n\n"
"float fromHalf2(vec2 pair) {\n"
" return utof(packHalf2x16(pair));\n"
"}\n\n"
"vec2 toHalf2(float value) {\n"
" return unpackHalf2x16(ftou(value));\n"
"}\n\n";
}
ProgramResult Decompile(const ShaderIR& ir, Maxwell::ShaderStage stage, const std::string& suffix) {
GLSLDecompiler decompiler(ir, stage, suffix);
decompiler.Decompile();
return {decompiler.GetResult(), decompiler.GetShaderEntries()};
}
} // namespace OpenGL::GLShader
