src/tint/lang/wgsl/resolver/dependency_graph.h - tint - Git at Google

 // Copyright 2021 The Dawn & Tint Authors
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are met:
 //
 // 1. Redistributions of source code must retain the above copyright notice, this
 //    list of conditions and the following disclaimer.
 //
 // 2. Redistributions in binary form must reproduce the above copyright notice,
 //    this list of conditions and the following disclaimer in the documentation
 //    and/or other materials provided with the distribution.
 //
 // 3. Neither the name of the copyright holder nor the names of its
 //    contributors may be used to endorse or promote products derived from
 //    this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 #ifndef SRC_TINT_LANG_WGSL_RESOLVER_DEPENDENCY_GRAPH_H_
 #define SRC_TINT_LANG_WGSL_RESOLVER_DEPENDENCY_GRAPH_H_

 #include <string>
 #include <vector>

 #include "src/tint/lang/core/access.h"
 #include "src/tint/lang/core/builtin_type.h"
 #include "src/tint/lang/core/builtin_value.h"
 #include "src/tint/lang/core/interpolation_sampling.h"
 #include "src/tint/lang/core/interpolation_type.h"
 #include "src/tint/lang/core/texel_format.h"
 #include "src/tint/lang/wgsl/ast/module.h"
 #include "src/tint/lang/wgsl/builtin_fn.h"
 #include "src/tint/utils/containers/hashmap.h"
 #include "src/tint/utils/diagnostic/diagnostic.h"

 namespace tint::resolver {

 /// ResolvedIdentifier holds the resolution of an ast::Identifier.
 /// Can hold one of:
 /// - UnresolvedIdentifier
 /// - const ast::TypeDecl*  (as const ast::Node*)
 /// - const ast::Variable*  (as const ast::Node*)
 /// - const ast::Function*  (as const ast::Node*)
 /// - wgsl::BuiltinFn
 /// - core::Access
 /// - core::AddressSpace
 /// - core::BuiltinType
 /// - core::BuiltinValue
 /// - core::InterpolationSampling
 /// - core::InterpolationType
 /// - core::TexelFormat
 class ResolvedIdentifier {
   public:
     /// UnresolvedIdentifier is the variant value used to represent an unresolved identifier
     struct UnresolvedIdentifier {
         /// Name of the unresolved identifier
         std::string name;
     };

     /// Constructor
     /// @param value the resolved identifier value
     template <typename T>
     ResolvedIdentifier(T value) : value_(value) {}  // NOLINT(runtime/explicit)

     /// @return the UnresolvedIdentifier if the identifier was not resolved
     const UnresolvedIdentifier* Unresolved() const {
         if (auto n = std::get_if<UnresolvedIdentifier>(&value_)) {
             return n;
         }
         return nullptr;
     }

     /// @return the node pointer if the ResolvedIdentifier holds an AST node, otherwise nullptr
     const ast::Node* Node() const {
         if (auto n = std::get_if<const ast::Node*>(&value_)) {
             return *n;
         }
         return nullptr;
     }

     /// @return the builtin function if the ResolvedIdentifier holds wgsl::BuiltinFn, otherwise
     /// wgsl::BuiltinFn::kNone
     wgsl::BuiltinFn BuiltinFn() const {
         if (auto n = std::get_if<wgsl::BuiltinFn>(&value_)) {
             return *n;
         }
         return wgsl::BuiltinFn::kNone;
     }

     /// @return the access if the ResolvedIdentifier holds core::Access, otherwise
     /// core::Access::kUndefined
     core::Access Access() const {
         if (auto n = std::get_if<core::Access>(&value_)) {
             return *n;
         }
         return core::Access::kUndefined;
     }

     /// @return the address space if the ResolvedIdentifier holds core::AddressSpace, otherwise
     /// core::AddressSpace::kUndefined
     core::AddressSpace AddressSpace() const {
         if (auto n = std::get_if<core::AddressSpace>(&value_)) {
             return *n;
         }
         return core::AddressSpace::kUndefined;
     }

     /// @return the builtin type if the ResolvedIdentifier holds core::BuiltinType, otherwise
     /// core::BuiltinType::kUndefined
     core::BuiltinType BuiltinType() const {
         if (auto n = std::get_if<core::BuiltinType>(&value_)) {
             return *n;
         }
         return core::BuiltinType::kUndefined;
     }

     /// @return the builtin value if the ResolvedIdentifier holds core::BuiltinValue, otherwise
     /// core::BuiltinValue::kUndefined
     core::BuiltinValue BuiltinValue() const {
         if (auto n = std::get_if<core::BuiltinValue>(&value_)) {
             return *n;
         }
         return core::BuiltinValue::kUndefined;
     }

     /// @return the texel format if the ResolvedIdentifier holds type::InterpolationSampling,
     /// otherwise type::InterpolationSampling::kUndefined
     core::InterpolationSampling InterpolationSampling() const {
         if (auto n = std::get_if<core::InterpolationSampling>(&value_)) {
             return *n;
         }
         return core::InterpolationSampling::kUndefined;
     }

     /// @return the texel format if the ResolvedIdentifier holds type::InterpolationType,
     /// otherwise type::InterpolationType::kUndefined
     core::InterpolationType InterpolationType() const {
         if (auto n = std::get_if<core::InterpolationType>(&value_)) {
             return *n;
         }
         return core::InterpolationType::kUndefined;
     }

     /// @return the texel format if the ResolvedIdentifier holds type::TexelFormat, otherwise
     /// type::TexelFormat::kUndefined
     core::TexelFormat TexelFormat() const {
         if (auto n = std::get_if<core::TexelFormat>(&value_)) {
             return *n;
         }
         return core::TexelFormat::kUndefined;
     }

     /// @param value the value to compare the ResolvedIdentifier to
     /// @return true if the ResolvedIdentifier is equal to @p value
     template <typename T>
     bool operator==(const T& value) const {
         if (auto n = std::get_if<T>(&value_)) {
             return *n == value;
         }
         return false;
     }

     /// @param other the other value to compare to this
     /// @return true if this ResolvedIdentifier and @p other are not equal
     template <typename T>
     bool operator!=(const T& other) const {
         return !(*this == other);
     }

     /// @return a description of the resolved symbol
     std::string String() const;

   private:
     std::variant<UnresolvedIdentifier,
                  const ast::Node*,
                  wgsl::BuiltinFn,
                  core::Access,
                  core::AddressSpace,
                  core::BuiltinType,
                  core::BuiltinValue,
                  core::InterpolationSampling,
                  core::InterpolationType,
                  core::TexelFormat>
         value_;
 };

 /// DependencyGraph holds information about module-scope declaration dependency
 /// analysis and symbol resolutions.
 struct DependencyGraph {
     /// Constructor
     DependencyGraph();
     /// Move-constructor
     DependencyGraph(DependencyGraph&&);
     /// Destructor
     ~DependencyGraph();

     /// Build() performs symbol resolution and dependency analysis on `module`,
     /// populating `output` with the resulting dependency graph.
     /// @param module the AST module to analyse
     /// @param diagnostics the diagnostic list to populate with errors / warnings
     /// @param output the resulting DependencyGraph
     /// @returns true on success, false on error
     static bool Build(const ast::Module& module, diag::List& diagnostics, DependencyGraph& output);

     /// All globals in dependency-sorted order.
     Vector<const ast::Node*, 32> ordered_globals;

     /// Map of ast::Identifier to a ResolvedIdentifier
     Hashmap<const ast::Identifier*, ResolvedIdentifier, 64> resolved_identifiers;

     /// Map of ast::Variable to a type, function, or variable that is shadowed by
     /// the variable key. A declaration (X) shadows another (Y) if X and Y use
     /// the same symbol, and X is declared in a sub-scope of the scope that
     /// declares Y.
     Hashmap<const ast::Variable*, const ast::Node*, 16> shadows;
 };

 }  // namespace tint::resolver

 #endif  // SRC_TINT_LANG_WGSL_RESOLVER_DEPENDENCY_GRAPH_H_
	// Copyright 2021 The Dawn & Tint Authors
	//
	// Redistribution and use in source and binary forms, with or without
	// modification, are permitted provided that the following conditions are met:
	//
	// 1. Redistributions of source code must retain the above copyright notice, this
	// list of conditions and the following disclaimer.
	//
	// 2. Redistributions in binary form must reproduce the above copyright notice,
	// this list of conditions and the following disclaimer in the documentation
	// and/or other materials provided with the distribution.
	//
	// 3. Neither the name of the copyright holder nor the names of its
	// contributors may be used to endorse or promote products derived from
	// this software without specific prior written permission.
	//
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
	// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	#ifndef SRC_TINT_LANG_WGSL_RESOLVER_DEPENDENCY_GRAPH_H_
	#define SRC_TINT_LANG_WGSL_RESOLVER_DEPENDENCY_GRAPH_H_

	#include <string>
	#include <vector>

	#include "src/tint/lang/core/access.h"
	#include "src/tint/lang/core/builtin_type.h"
	#include "src/tint/lang/core/builtin_value.h"
	#include "src/tint/lang/core/interpolation_sampling.h"
	#include "src/tint/lang/core/interpolation_type.h"
	#include "src/tint/lang/core/texel_format.h"
	#include "src/tint/lang/wgsl/ast/module.h"
	#include "src/tint/lang/wgsl/builtin_fn.h"
	#include "src/tint/utils/containers/hashmap.h"
	#include "src/tint/utils/diagnostic/diagnostic.h"

	namespace tint::resolver {

	/// ResolvedIdentifier holds the resolution of an ast::Identifier.
	/// Can hold one of:
	/// - UnresolvedIdentifier
	/// - const ast::TypeDecl* (as const ast::Node*)
	/// - const ast::Variable* (as const ast::Node*)
	/// - const ast::Function* (as const ast::Node*)
	/// - wgsl::BuiltinFn
	/// - core::Access
	/// - core::AddressSpace
	/// - core::BuiltinType
	/// - core::BuiltinValue
	/// - core::InterpolationSampling
	/// - core::InterpolationType
	/// - core::TexelFormat
	class ResolvedIdentifier {
	public:
	/// UnresolvedIdentifier is the variant value used to represent an unresolved identifier
	struct UnresolvedIdentifier {
	/// Name of the unresolved identifier
	std::string name;
	};

	/// Constructor
	/// @param value the resolved identifier value
	template <typename T>
	ResolvedIdentifier(T value) : value_(value) {} // NOLINT(runtime/explicit)

	/// @return the UnresolvedIdentifier if the identifier was not resolved
	const UnresolvedIdentifier* Unresolved() const {
	if (auto n = std::get_if<UnresolvedIdentifier>(&value_)) {
	return n;
	}
	return nullptr;
	}

	/// @return the node pointer if the ResolvedIdentifier holds an AST node, otherwise nullptr
	const ast::Node* Node() const {
	if (auto n = std::get_if<const ast::Node*>(&value_)) {
	return *n;
	}
	return nullptr;
	}

	/// @return the builtin function if the ResolvedIdentifier holds wgsl::BuiltinFn, otherwise
	/// wgsl::BuiltinFn::kNone
	wgsl::BuiltinFn BuiltinFn() const {
	if (auto n = std::get_if<wgsl::BuiltinFn>(&value_)) {
	return *n;
	}
	return wgsl::BuiltinFn::kNone;
	}

	/// @return the access if the ResolvedIdentifier holds core::Access, otherwise
	/// core::Access::kUndefined
	core::Access Access() const {
	if (auto n = std::get_if<core::Access>(&value_)) {
	return *n;
	}
	return core::Access::kUndefined;
	}

	/// @return the address space if the ResolvedIdentifier holds core::AddressSpace, otherwise
	/// core::AddressSpace::kUndefined
	core::AddressSpace AddressSpace() const {
	if (auto n = std::get_if<core::AddressSpace>(&value_)) {
	return *n;
	}
	return core::AddressSpace::kUndefined;
	}

	/// @return the builtin type if the ResolvedIdentifier holds core::BuiltinType, otherwise
	/// core::BuiltinType::kUndefined
	core::BuiltinType BuiltinType() const {
	if (auto n = std::get_if<core::BuiltinType>(&value_)) {
	return *n;
	}
	return core::BuiltinType::kUndefined;
	}

	/// @return the builtin value if the ResolvedIdentifier holds core::BuiltinValue, otherwise
	/// core::BuiltinValue::kUndefined
	core::BuiltinValue BuiltinValue() const {
	if (auto n = std::get_if<core::BuiltinValue>(&value_)) {
	return *n;
	}
	return core::BuiltinValue::kUndefined;
	}

	/// @return the texel format if the ResolvedIdentifier holds type::InterpolationSampling,
	/// otherwise type::InterpolationSampling::kUndefined
	core::InterpolationSampling InterpolationSampling() const {
	if (auto n = std::get_if<core::InterpolationSampling>(&value_)) {
	return *n;
	}
	return core::InterpolationSampling::kUndefined;
	}

	/// @return the texel format if the ResolvedIdentifier holds type::InterpolationType,
	/// otherwise type::InterpolationType::kUndefined
	core::InterpolationType InterpolationType() const {
	if (auto n = std::get_if<core::InterpolationType>(&value_)) {
	return *n;
	}
	return core::InterpolationType::kUndefined;
	}

	/// @return the texel format if the ResolvedIdentifier holds type::TexelFormat, otherwise
	/// type::TexelFormat::kUndefined
	core::TexelFormat TexelFormat() const {
	if (auto n = std::get_if<core::TexelFormat>(&value_)) {
	return *n;
	}
	return core::TexelFormat::kUndefined;
	}

	/// @param value the value to compare the ResolvedIdentifier to
	/// @return true if the ResolvedIdentifier is equal to @p value
	template <typename T>
	bool operator==(const T& value) const {
	if (auto n = std::get_if<T>(&value_)) {
	return *n == value;
	}
	return false;
	}

	/// @param other the other value to compare to this
	/// @return true if this ResolvedIdentifier and @p other are not equal
	template <typename T>
	bool operator!=(const T& other) const {
	return !(*this == other);
	}

	/// @return a description of the resolved symbol
	std::string String() const;

	private:
	std::variant<UnresolvedIdentifier,
	const ast::Node*,
	wgsl::BuiltinFn,
	core::Access,
	core::AddressSpace,
	core::BuiltinType,
	core::BuiltinValue,
	core::InterpolationSampling,
	core::InterpolationType,
	core::TexelFormat>
	value_;
	};

	/// DependencyGraph holds information about module-scope declaration dependency
	/// analysis and symbol resolutions.
	struct DependencyGraph {
	/// Constructor
	DependencyGraph();
	/// Move-constructor
	DependencyGraph(DependencyGraph&&);
	/// Destructor
	~DependencyGraph();

	/// Build() performs symbol resolution and dependency analysis on `module`,
	/// populating `output` with the resulting dependency graph.
	/// @param module the AST module to analyse
	/// @param diagnostics the diagnostic list to populate with errors / warnings
	/// @param output the resulting DependencyGraph
	/// @returns true on success, false on error
	static bool Build(const ast::Module& module, diag::List& diagnostics, DependencyGraph& output);

	/// All globals in dependency-sorted order.
	Vector<const ast::Node*, 32> ordered_globals;

	/// Map of ast::Identifier to a ResolvedIdentifier
	Hashmap<const ast::Identifier*, ResolvedIdentifier, 64> resolved_identifiers;

	/// Map of ast::Variable to a type, function, or variable that is shadowed by
	/// the variable key. A declaration (X) shadows another (Y) if X and Y use
	/// the same symbol, and X is declared in a sub-scope of the scope that
	/// declares Y.
	Hashmap<const ast::Variable, const ast::Node, 16> shadows;
	};

	} // namespace tint::resolver

	#endif // SRC_TINT_LANG_WGSL_RESOLVER_DEPENDENCY_GRAPH_H_