Shader/GlslWriter: Improve removal of unused code

This commit is contained in:
Jérôme Leclercq 2022-02-27 18:42:41 +01:00
parent 55a5ae0648
commit fbae413620
4 changed files with 34 additions and 8 deletions

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@ -17,16 +17,23 @@ namespace Nz::ShaderAst
class NAZARA_SHADER_API EliminateUnusedPassVisitor : AstCloner class NAZARA_SHADER_API EliminateUnusedPassVisitor : AstCloner
{ {
public: public:
struct Config;
EliminateUnusedPassVisitor() = default; EliminateUnusedPassVisitor() = default;
EliminateUnusedPassVisitor(const EliminateUnusedPassVisitor&) = delete; EliminateUnusedPassVisitor(const EliminateUnusedPassVisitor&) = delete;
EliminateUnusedPassVisitor(EliminateUnusedPassVisitor&&) = delete; EliminateUnusedPassVisitor(EliminateUnusedPassVisitor&&) = delete;
~EliminateUnusedPassVisitor() = default; ~EliminateUnusedPassVisitor() = default;
StatementPtr Process(Statement& statement); StatementPtr Process(Statement& statement, const Config& config = {});
EliminateUnusedPassVisitor& operator=(const EliminateUnusedPassVisitor&) = delete; EliminateUnusedPassVisitor& operator=(const EliminateUnusedPassVisitor&) = delete;
EliminateUnusedPassVisitor& operator=(EliminateUnusedPassVisitor&&) = delete; EliminateUnusedPassVisitor& operator=(EliminateUnusedPassVisitor&&) = delete;
struct Config
{
ShaderStageTypeFlags usedShaderStages = ShaderStageType_All;
};
private: private:
using AstCloner::Clone; using AstCloner::Clone;
StatementPtr Clone(DeclareExternalStatement& node) override; StatementPtr Clone(DeclareExternalStatement& node) override;
@ -42,7 +49,7 @@ namespace Nz::ShaderAst
Context* m_context; Context* m_context;
}; };
inline StatementPtr EliminateUnusedPass(Statement& ast); inline StatementPtr EliminateUnusedPass(Statement& ast, const EliminateUnusedPassVisitor::Config& config = {});
} }
#include <Nazara/Shader/Ast/EliminateUnusedPassVisitor.inl> #include <Nazara/Shader/Ast/EliminateUnusedPassVisitor.inl>

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@ -7,10 +7,10 @@
namespace Nz::ShaderAst namespace Nz::ShaderAst
{ {
inline StatementPtr EliminateUnusedPass(Statement& ast) inline StatementPtr EliminateUnusedPass(Statement& ast, const EliminateUnusedPassVisitor::Config& config)
{ {
EliminateUnusedPassVisitor visitor; EliminateUnusedPassVisitor visitor;
return visitor.Process(ast); return visitor.Process(ast, config);
} }
} }

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@ -29,6 +29,11 @@ namespace Nz::ShaderAst
struct UsageChecker : AstRecursiveVisitor struct UsageChecker : AstRecursiveVisitor
{ {
UsageChecker(const EliminateUnusedPassVisitor::Config& Config) :
config(Config)
{
}
struct UsageSet; struct UsageSet;
void Resolve() void Resolve()
@ -129,7 +134,11 @@ namespace Nz::ShaderAst
} }
if (node.entryStage.HasValue()) if (node.entryStage.HasValue())
{
ShaderStageType shaderStage = node.entryStage.GetResultingValue();
if (shaderStage & config.usedShaderStages)
globalUsage.usedFunctions.UnboundedSet(*node.funcIndex); globalUsage.usedFunctions.UnboundedSet(*node.funcIndex);
}
currentFunctionIndex = node.funcIndex; currentFunctionIndex = node.funcIndex;
AstRecursiveVisitor::Visit(node); AstRecursiveVisitor::Visit(node);
@ -195,6 +204,7 @@ namespace Nz::ShaderAst
Bitset<> usedVariables; Bitset<> usedVariables;
}; };
const EliminateUnusedPassVisitor::Config& config;
std::optional<std::size_t> currentFunctionIndex; std::optional<std::size_t> currentFunctionIndex;
std::optional<std::size_t> currentVariableDeclIndex; std::optional<std::size_t> currentVariableDeclIndex;
std::unordered_map<std::size_t, UsageSet> functionUsages; std::unordered_map<std::size_t, UsageSet> functionUsages;
@ -207,12 +217,17 @@ namespace Nz::ShaderAst
struct EliminateUnusedPassVisitor::Context struct EliminateUnusedPassVisitor::Context
{ {
Context(const Config& config) :
usageChecker(config)
{
}
UsageChecker usageChecker; UsageChecker usageChecker;
}; };
StatementPtr EliminateUnusedPassVisitor::Process(Statement& statement) StatementPtr EliminateUnusedPassVisitor::Process(Statement& statement, const Config& config)
{ {
Context context; Context context(config);
statement.Visit(context.usageChecker); statement.Visit(context.usageChecker);
context.usageChecker.Resolve(); context.usageChecker.Resolve();

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@ -180,8 +180,12 @@ namespace Nz
{ {
ShaderAst::StatementPtr tempAst; ShaderAst::StatementPtr tempAst;
ShaderAst::EliminateUnusedPassVisitor::Config eliminateUnunsedConfig;
if (shaderStage)
eliminateUnunsedConfig.usedShaderStages = *shaderStage;
tempAst = ShaderAst::PropagateConstants(*targetAst); tempAst = ShaderAst::PropagateConstants(*targetAst);
optimizedAst = ShaderAst::EliminateUnusedPass(*tempAst); optimizedAst = ShaderAst::EliminateUnusedPass(*tempAst, eliminateUnunsedConfig);
targetAst = optimizedAst.get(); targetAst = optimizedAst.get();
} }