franklinblanco/yuzu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

gl_shader_decompiler: Implement AST decompiling

Browse Source
This commit is contained in:
Fernando Sahmkow 2019-06-29 01:44:07 -04:00 committed by FernandoS27
parent 6fdd501113
commit 38fc995f6c
11 changed files with 358 additions and 63 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

271
src/video_core/renderer_opengl/gl_shader_decompiler.cpp
View File

@ -20,6 +20,7 @@
#include "video_core/renderer_opengl/gl_rasterizer.h"
#include "video_core/renderer_opengl/gl_shader_decompiler.h"
#include "video_core/shader/node.h"
#include "video_core/shader/ast.h"
#include "video_core/shader/shader_ir.h"
namespace OpenGL::GLShader {
@ -334,43 +335,26 @@ constexpr bool IsVertexShader(ProgramType stage) {
return stage == ProgramType::VertexA || stage == ProgramType::VertexB;
}
class ASTDecompiler;
class ExprDecompiler;
class GLSLDecompiler final {
public:
explicit GLSLDecompiler(const Device& device, const ShaderIR& ir, ProgramType stage,
std::string suffix)
: device{device}, ir{ir}, stage{stage}, suffix{suffix}, header{ir.GetHeader()} {}
void Decompile() {
DeclareVertex();
DeclareGeometry();
DeclareRegisters();
DeclarePredicates();
DeclareLocalMemory();
DeclareSharedMemory();
DeclareInternalFlags();
DeclareInputAttributes();
DeclareOutputAttributes();
DeclareConstantBuffers();
DeclareGlobalMemory();
DeclareSamplers();
DeclarePhysicalAttributeReader();
DeclareImages();
code.AddLine("void execute_{}() {{", suffix);
++code.scope;
void DecompileBranchMode() {
// VM's program counter
const auto first_address = ir.GetBasicBlocks().begin()->first;
code.AddLine("uint jmp_to = {}U;", first_address);
// 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.
if (!ir.IsFlowStackDisabled()) {
constexpr u32 FLOW_STACK_SIZE = 20;
for (const auto stack : std::array{MetaStackClass::Ssy, MetaStackClass::Pbk}) {
code.AddLine("uint {}[{}];", FlowStackName(stack), FLOW_STACK_SIZE);
code.AddLine("uint {} = 0U;", FlowStackTopName(stack));
}
constexpr u32 FLOW_STACK_SIZE = 20;
for (const auto stack : std::array{MetaStackClass::Ssy, MetaStackClass::Pbk}) {
code.AddLine("uint {}[{}];", FlowStackName(stack), FLOW_STACK_SIZE);
code.AddLine("uint {} = 0u;", FlowStackTopName(stack));
}
code.AddLine("while (true) {{");
@ -392,10 +376,37 @@ public:
code.AddLine("default: return;");
code.AddLine("}}");
for (std::size_t i = 0; i < 2; ++i) {
--code.scope;
code.AddLine("}}");
--code.scope;
code.AddLine("}}");
}
void DecompileAST();
void Decompile() {
DeclareVertex();
DeclareGeometry();
DeclareRegisters();
DeclarePredicates();
DeclareLocalMemory();
DeclareInternalFlags();
DeclareInputAttributes();
DeclareOutputAttributes();
DeclareConstantBuffers();
DeclareGlobalMemory();
DeclareSamplers();
DeclarePhysicalAttributeReader();
code.AddLine("void execute_{}() {{", suffix);
++code.scope;
if (ir.IsDecompiled()) {
DecompileAST();
} else {
DecompileBranchMode();
}
--code.scope;
code.AddLine("}}");
}
std::string GetResult() {
@ -424,6 +435,9 @@ public:
}
private:
friend class ASTDecompiler;
friend class ExprDecompiler;
void DeclareVertex() {
if (!IsVertexShader(stage))
return;
@ -1821,7 +1835,7 @@ private:
return {};
}
Expression Exit(Operation operation) {
Expression WriteExit() {
if (stage != ProgramType::Fragment) {
code.AddLine("return;");
return {};
@ -1861,6 +1875,10 @@ private:
return {};
}
Expression Exit(Operation operation) {
return WriteExit();
}
Expression Discard(Operation operation) {
// Enclose "discard" in a conditional, so that GLSL compilation does not complain
// about unexecuted instructions that may follow this.
@ -2253,6 +2271,201 @@ private:
ShaderWriter code;
};
const std::string flow_var = "flow_var_";
class ExprDecompiler {
public:
ExprDecompiler(GLSLDecompiler& decomp) : decomp{decomp} {}
void operator()(VideoCommon::Shader::ExprAnd& expr) {
inner += "( ";
std::visit(*this, *expr.operand1);
inner += " && ";
std::visit(*this, *expr.operand2);
inner += ')';
}
void operator()(VideoCommon::Shader::ExprOr& expr) {
inner += "( ";
std::visit(*this, *expr.operand1);
inner += " || ";
std::visit(*this, *expr.operand2);
inner += ')';
}
void operator()(VideoCommon::Shader::ExprNot& expr) {
inner += '!';
std::visit(*this, *expr.operand1);
}
void operator()(VideoCommon::Shader::ExprPredicate& expr) {
auto pred = static_cast<Tegra::Shader::Pred>(expr.predicate);
inner += decomp.GetPredicate(pred);
}
void operator()(VideoCommon::Shader::ExprCondCode& expr) {
Node cc = decomp.ir.GetConditionCode(expr.cc);
std::string target;
if (const auto pred = std::get_if<PredicateNode>(&*cc)) {
const auto index = pred->GetIndex();
switch (index) {
case Tegra::Shader::Pred::NeverExecute:
target = "false";
case Tegra::Shader::Pred::UnusedIndex:
target = "true";
default:
target = decomp.GetPredicate(index);
}
} else if (const auto flag = std::get_if<InternalFlagNode>(&*cc)) {
target = decomp.GetInternalFlag(flag->GetFlag());
}
inner += target;
}
void operator()(VideoCommon::Shader::ExprVar& expr) {
inner += flow_var + std::to_string(expr.var_index);
}
void operator()(VideoCommon::Shader::ExprBoolean& expr) {
inner += expr.value ? "true" : "false";
}
std::string& GetResult() {
return inner;
}
private:
std::string inner{};
GLSLDecompiler& decomp;
};
class ASTDecompiler {
public:
ASTDecompiler(GLSLDecompiler& decomp) : decomp{decomp} {}
void operator()(VideoCommon::Shader::ASTProgram& ast) {
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
}
void operator()(VideoCommon::Shader::ASTIfThen& ast) {
ExprDecompiler expr_parser{decomp};
std::visit(expr_parser, *ast.condition);
decomp.code.AddLine("if ({}) {{", expr_parser.GetResult());
decomp.code.scope++;
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
decomp.code.scope--;
decomp.code.AddLine("}}");
}
void operator()(VideoCommon::Shader::ASTIfElse& ast) {
decomp.code.AddLine("else {{");
decomp.code.scope++;
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
decomp.code.scope--;
decomp.code.AddLine("}}");
}
void operator()(VideoCommon::Shader::ASTBlockEncoded& ast) {
UNREACHABLE();
}
void operator()(VideoCommon::Shader::ASTBlockDecoded& ast) {
decomp.VisitBlock(ast.nodes);
}
void operator()(VideoCommon::Shader::ASTVarSet& ast) {
ExprDecompiler expr_parser{decomp};
std::visit(expr_parser, *ast.condition);
decomp.code.AddLine("{}{} = {};", flow_var, ast.index, expr_parser.GetResult());
}
void operator()(VideoCommon::Shader::ASTLabel& ast) {
decomp.code.AddLine("// Label_{}:", ast.index);
}
void operator()(VideoCommon::Shader::ASTGoto& ast) {
UNREACHABLE();
}
void operator()(VideoCommon::Shader::ASTDoWhile& ast) {
ExprDecompiler expr_parser{decomp};
std::visit(expr_parser, *ast.condition);
decomp.code.AddLine("do {{");
decomp.code.scope++;
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
decomp.code.scope--;
decomp.code.AddLine("}} while({});", expr_parser.GetResult());
}
void operator()(VideoCommon::Shader::ASTReturn& ast) {
bool is_true = VideoCommon::Shader::ExprIsTrue(ast.condition);
if (!is_true) {
ExprDecompiler expr_parser{decomp};
std::visit(expr_parser, *ast.condition);
decomp.code.AddLine("if ({}) {{", expr_parser.GetResult());
decomp.code.scope++;
}
if (ast.kills) {
decomp.code.AddLine("discard;");
} else {
decomp.WriteExit();
}
if (!is_true) {
decomp.code.scope--;
decomp.code.AddLine("}}");
}
}
void operator()(VideoCommon::Shader::ASTBreak& ast) {
bool is_true = VideoCommon::Shader::ExprIsTrue(ast.condition);
if (!is_true) {
ExprDecompiler expr_parser{decomp};
std::visit(expr_parser, *ast.condition);
decomp.code.AddLine("if ({}) {{", expr_parser.GetResult());
decomp.code.scope++;
}
decomp.code.AddLine("break;");
if (!is_true) {
decomp.code.scope--;
decomp.code.AddLine("}}");
}
}
void Visit(VideoCommon::Shader::ASTNode& node) {
std::visit(*this, *node->GetInnerData());
}
private:
GLSLDecompiler& decomp;
};
void GLSLDecompiler::DecompileAST() {
u32 num_flow_variables = ir.GetASTNumVariables();
for (u32 i = 0; i < num_flow_variables; i++) {
code.AddLine("bool {}{} = false;", flow_var, i);
}
ASTDecompiler decompiler{*this};
VideoCommon::Shader::ASTNode program = ir.GetASTProgram();
decompiler.Visit(program);
}
} // Anonymous namespace
std::string GetCommonDeclarations() {

10
src/video_core/shader/ast.cpp
View File

@ -372,13 +372,13 @@ ASTManager::~ASTManager() {
void ASTManager::Init() {
main_node = ASTBase::Make<ASTProgram>(ASTNode{});
program = std::get_if<ASTProgram>(main_node->GetInnerData());
true_condition = MakeExpr<ExprBoolean>(true);
false_condition = MakeExpr<ExprBoolean>(false);
}
ASTManager::ASTManager(ASTManager&& other)
: labels_map(std::move(other.labels_map)), labels_count{other.labels_count},
gotos(std::move(other.gotos)), labels(std::move(other.labels)), variables{other.variables},
program{other.program}, main_node{other.main_node}, true_condition{other.true_condition} {
program{other.program}, main_node{other.main_node}, false_condition{other.false_condition} {
other.main_node.reset();
}
@ -390,7 +390,7 @@ ASTManager& ASTManager::operator=(ASTManager&& other) {
variables = other.variables;
program = other.program;
main_node = other.main_node;
true_condition = other.true_condition;
false_condition = other.false_condition;
other.main_node.reset();
return *this;
@ -594,7 +594,7 @@ void ASTManager::MoveOutward(ASTNode goto_node) {
u32 var_index = NewVariable();
Expr var_condition = MakeExpr<ExprVar>(var_index);
ASTNode var_node = ASTBase::Make<ASTVarSet>(parent, var_index, condition);
ASTNode var_node_init = ASTBase::Make<ASTVarSet>(parent, var_index, true_condition);
ASTNode var_node_init = ASTBase::Make<ASTVarSet>(parent, var_index, false_condition);
zipper2.InsertBefore(var_node_init, parent);
zipper.InsertAfter(var_node, prev);
goto_node->SetGotoCondition(var_condition);
@ -605,7 +605,7 @@ void ASTManager::MoveOutward(ASTNode goto_node) {
u32 var_index = NewVariable();
Expr var_condition = MakeExpr<ExprVar>(var_index);
ASTNode var_node = ASTBase::Make<ASTVarSet>(parent, var_index, condition);
ASTNode var_node_init = ASTBase::Make<ASTVarSet>(parent, var_index, true_condition);
ASTNode var_node_init = ASTBase::Make<ASTVarSet>(parent, var_index, false_condition);
if (is_if) {
zipper2.InsertBefore(var_node_init, parent);
} else {

18
src/video_core/shader/ast.h
View File

@ -141,8 +141,6 @@ public:
Expr condition;
};
using TransformCallback = std::function<NodeBlock(u32 start, u32 end)>;
class ASTBase {
public:
explicit ASTBase(ASTNode parent, ASTData data) : parent{parent}, data{data} {}
@ -233,11 +231,7 @@ public:
return std::holds_alternative<ASTBlockEncoded>(data);
}
void TransformBlockEncoded(TransformCallback& callback) {
auto block = std::get_if<ASTBlockEncoded>(&data);
const u32 start = block->start;
const u32 end = block->end;
NodeBlock nodes = callback(start, end);
void TransformBlockEncoded(NodeBlock& nodes) {
data = ASTBlockDecoded(nodes);
}
@ -309,16 +303,20 @@ public:
void SanityCheck();
bool IsFullyDecompiled() {
bool IsFullyDecompiled() const {
return gotos.size() == 0;
}
ASTNode GetProgram() {
ASTNode GetProgram() const {
return main_node;
}
void Clear();
u32 GetVariables() const {
return variables;
}
private:
bool IndirectlyRelated(ASTNode first, ASTNode second);
@ -343,7 +341,7 @@ private:
u32 variables{};
ASTProgram* program{};
ASTNode main_node{};
Expr true_condition{};
Expr false_condition{};
};
} // namespace VideoCommon::Shader

2
src/video_core/shader/control_flow.cpp
View File

@ -425,7 +425,7 @@ void InsertBranch(ASTManager& mm, const BlockBranchInfo& branch) {
}
if (cond.predicate != Pred::UnusedIndex) {
u32 pred = static_cast<u32>(cond.predicate);
bool negate;
bool negate = false;
if (pred > 7) {
negate = true;
pred -= 8;

2
src/video_core/shader/control_flow.h
View File

@ -74,6 +74,6 @@ struct ShaderCharacteristics {
};
std::unique_ptr<ShaderCharacteristics> ScanFlow(const ProgramCode& program_code, u32 program_size,
u32 start_address, ASTManager& manager);
u32 start_address, ASTManager& manager);
} // namespace VideoCommon::Shader

70
src/video_core/shader/decode.cpp
View File

@ -35,10 +35,73 @@ constexpr bool IsSchedInstruction(u32 offset, u32 main_offset) {
} // namespace
class ASTDecoder {
public:
ASTDecoder(ShaderIR& ir) : ir(ir) {}
void operator()(ASTProgram& ast) {
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
}
void operator()(ASTIfThen& ast) {
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
}
void operator()(ASTIfElse& ast) {
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
}
void operator()(ASTBlockEncoded& ast) {}
void operator()(ASTBlockDecoded& ast) {}
void operator()(ASTVarSet& ast) {}
void operator()(ASTLabel& ast) {}
void operator()(ASTGoto& ast) {}
void operator()(ASTDoWhile& ast) {
ASTNode current = ast.nodes.GetFirst();
while (current) {
Visit(current);
current = current->GetNext();
}
}
void operator()(ASTReturn& ast) {}
void operator()(ASTBreak& ast) {}
void Visit(ASTNode& node) {
std::visit(*this, *node->GetInnerData());
if (node->IsBlockEncoded()) {
auto block = std::get_if<ASTBlockEncoded>(node->GetInnerData());
NodeBlock bb = ir.DecodeRange(block->start, block->end);
node->TransformBlockEncoded(bb);
}
}
private:
ShaderIR& ir;
};
void ShaderIR::Decode() {
std::memcpy(&header, program_code.data(), sizeof(Tegra::Shader::Header));
disable_flow_stack = false;
decompiled = false;
const auto info =
ScanFlow(program_code, program_size, main_offset, program_manager);
if (info) {
@ -46,7 +109,10 @@ void ShaderIR::Decode() {
coverage_begin = shader_info.start;
coverage_end = shader_info.end;
if (shader_info.decompiled) {
disable_flow_stack = true;
decompiled = true;
ASTDecoder decoder{*this};
ASTNode program = GetASTProgram();
decoder.Visit(program);
return;
}
LOG_WARNING(HW_GPU, "Flow Stack Removing Failed! Falling back to old method");

8
src/video_core/shader/decode/other.cpp
View File

@ -157,7 +157,7 @@ u32 ShaderIR::DecodeOther(NodeBlock& bb, u32 pc) {
UNIMPLEMENTED_IF_MSG(instr.bra.constant_buffer != 0,
"Constant buffer flow is not supported");
if (disable_flow_stack) {
if (decompiled) {
break;
}
@ -171,7 +171,7 @@ u32 ShaderIR::DecodeOther(NodeBlock& bb, u32 pc) {
UNIMPLEMENTED_IF_MSG(instr.bra.constant_buffer != 0,
"Constant buffer PBK is not supported");
if (disable_flow_stack) {
if (decompiled) {
break;
}
@ -186,7 +186,7 @@ u32 ShaderIR::DecodeOther(NodeBlock& bb, u32 pc) {
UNIMPLEMENTED_IF_MSG(cc != Tegra::Shader::ConditionCode::T, "SYNC condition code used: {}",
static_cast<u32>(cc));
if (disable_flow_stack) {
if (decompiled) {
break;
}
@ -198,7 +198,7 @@ u32 ShaderIR::DecodeOther(NodeBlock& bb, u32 pc) {
const Tegra::Shader::ConditionCode cc = instr.flow_condition_code;
UNIMPLEMENTED_IF_MSG(cc != Tegra::Shader::ConditionCode::T, "BRK condition code used: {}",
static_cast<u32>(cc));
if (disable_flow_stack) {
if (decompiled) {
break;
}

7
src/video_core/shader/expr.cpp
View File

@ -72,4 +72,11 @@ bool ExprAreOpposite(Expr first, Expr second) {
return false;
}
bool ExprIsTrue(Expr first) {
if (ExprIsBoolean(first)) {
return ExprBooleanGet(first);
}
return false;
}
} // namespace VideoCommon::Shader

2
src/video_core/shader/expr.h
View File

@ -115,4 +115,6 @@ Expr MakeExprAnd(Expr first, Expr second);
Expr MakeExprOr(Expr first, Expr second);
bool ExprIsTrue(Expr first);
} // namespace VideoCommon::Shader

6
src/video_core/shader/shader_ir.cpp
View File

@ -137,7 +137,7 @@ Node ShaderIR::GetOutputAttribute(Attribute::Index index, u64 element, Node buff
return MakeNode<AbufNode>(index, static_cast<u32>(element), std::move(buffer));
}
Node ShaderIR::GetInternalFlag(InternalFlag flag, bool negated) {
Node ShaderIR::GetInternalFlag(InternalFlag flag, bool negated) const {
const Node node = MakeNode<InternalFlagNode>(flag);
if (negated) {
return Operation(OperationCode::LogicalNegate, node);
@ -367,13 +367,13 @@ OperationCode ShaderIR::GetPredicateCombiner(PredOperation operation) {
return op->second;
}
Node ShaderIR::GetConditionCode(Tegra::Shader::ConditionCode cc) {
Node ShaderIR::GetConditionCode(Tegra::Shader::ConditionCode cc) const {
switch (cc) {
case Tegra::Shader::ConditionCode::NEU:
return GetInternalFlag(InternalFlag::Zero, true);
default:
UNIMPLEMENTED_MSG("Unimplemented condition code: {}", static_cast<u32>(cc));
return GetPredicate(static_cast<u64>(Pred::NeverExecute));
return MakeNode<PredicateNode>(Pred::NeverExecute, false);
}
}

25
src/video_core/shader/shader_ir.h
View File

@ -15,8 +15,8 @@
#include "video_core/engines/maxwell_3d.h"
#include "video_core/engines/shader_bytecode.h"
#include "video_core/engines/shader_header.h"
#include "video_core/shader/node.h"
#include "video_core/shader/ast.h"
#include "video_core/shader/node.h"
namespace VideoCommon::Shader {
@ -141,15 +141,27 @@ public:
return header;
}
bool IsFlowStackDisabled() const {
return disable_flow_stack;
bool IsDecompiled() const {
return decompiled;
}
ASTNode GetASTProgram() const {
return program_manager.GetProgram();
}
u32 GetASTNumVariables() const {
return program_manager.GetVariables();
}
u32 ConvertAddressToNvidiaSpace(const u32 address) const {
return (address - main_offset) * sizeof(Tegra::Shader::Instruction);
}
/// Returns a condition code evaluated from internal flags
Node GetConditionCode(Tegra::Shader::ConditionCode cc) const;
private:
friend class ASTDecoder;
void Decode();
NodeBlock DecodeRange(u32 begin, u32 end);
@ -214,7 +226,7 @@ private:
/// Generates a node representing an output attribute. Keeps track of used attributes.
Node GetOutputAttribute(Tegra::Shader::Attribute::Index index, u64 element, Node buffer);
/// Generates a node representing an internal flag
Node GetInternalFlag(InternalFlag flag, bool negated = false);
Node GetInternalFlag(InternalFlag flag, bool negated = false) const;
/// Generates a node representing a local memory address
Node GetLocalMemory(Node address);
/// Generates a node representing a shared memory address
@ -272,9 +284,6 @@ private:
/// Returns a predicate combiner operation
OperationCode GetPredicateCombiner(Tegra::Shader::PredOperation operation);
/// Returns a condition code evaluated from internal flags
Node GetConditionCode(Tegra::Shader::ConditionCode cc);
/// Accesses a texture sampler
const Sampler& GetSampler(const Tegra::Shader::Sampler& sampler,
Tegra::Shader::TextureType type, bool is_array, bool is_shadow);
@ -358,7 +367,7 @@ private:
const ProgramCode& program_code;
const u32 main_offset;
const std::size_t program_size;
bool disable_flow_stack{};
bool decompiled{};
u32 coverage_begin{};
u32 coverage_end{};