[ast] Capture global declaration order

Adds a vector<CastableBase*> to ast::Module which stores the list of
global variables, functions, and types, in the order that they were
declared.

This will be used to fix validation and backend issues around name
uniqueness.

Change-Id: I14491f6ebc0fc7341bd3fb3b3f408faa234a91f7
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/41301
Commit-Queue: James Price <jrprice@google.com>
Reviewed-by: dan sinclair <dsinclair@chromium.org>

src/ast/module.cc

@@ -29,18 +29,33 @@ namespace ast {
 
 Module::Module(const Source& source) : Base(source) {}
 
-Module::Module(const Source& source,
-               std::vector<type::Type*> constructed_types,
-               FunctionList functions,
-               VariableList global_variables)
-    : Base(source),
-      constructed_types_(std::move(constructed_types)),
-      functions_(std::move(functions)),
-      global_variables_(std::move(global_variables)) {}
+Module::Module(const Source& source, std::vector<CastableBase*> global_decls)
+    : Base(source), global_declarations_(std::move(global_decls)) {
+  for (auto* decl : global_declarations_) {
+    if (decl == nullptr) {
+      continue;
+    }
+
+    if (auto* ty = decl->As<type::Type>()) {
+      constructed_types_.push_back(ty);
+    } else if (auto* func = decl->As<Function>()) {
+      functions_.push_back(func);
+    } else if (auto* var = decl->As<Variable>()) {
+      global_variables_.push_back(var);
+    } else {
+      assert(false /* unreachable */);
+    }
+  }
+}
 
 Module::~Module() = default;
 
 bool Module::IsValid() const {
+  for (auto* decl : global_declarations_) {
+    if (decl == nullptr) {
+      return false;
+    }
+  }
   for (auto* var : global_variables_) {
     if (var == nullptr || !var->IsValid()) {
       return false;
@@ -76,9 +91,20 @@ bool Module::IsValid() const {
 }
 
 Module* Module::Clone(CloneContext* ctx) const {
-  return ctx->dst->create<Module>(ctx->Clone(constructed_types_),
-                                  ctx->Clone(functions_),
-                                  ctx->Clone(global_variables_));
+  std::vector<CastableBase*> global_decls;
+  for (auto* decl : global_declarations_) {
+    assert(decl);
+    if (auto* ty = decl->As<type::Type>()) {
+      global_decls.push_back(ctx->Clone(ty));
+    } else if (auto* func = decl->As<Function>()) {
+      global_decls.push_back(ctx->Clone(func));
+    } else if (auto* var = decl->As<Variable>()) {
+      global_decls.push_back(ctx->Clone(var));
+    } else {
+      assert(false /* unreachable */);
+    }
+  }
+  return ctx->dst->create<Module>(global_decls);
 }
 
 void Module::to_str(const semantic::Info& sem,

src/ast/module.h

@@ -36,21 +36,23 @@ class Module : public Castable<Module, Node> {
 
   /// Constructor
   /// @param source the source of the module
-  /// @param constructed_types the list of types explicitly declared in the AST
-  /// @param functions the list of program functions
-  /// @param global_variables the list of global variables
-  Module(const Source& source,
-         std::vector<type::Type*> constructed_types,
-         FunctionList functions,
-         VariableList global_variables);
+  /// @param global_decls the list of global types, functions, and variables, in
+  /// the order they were declared in the source program
+  Module(const Source& source, std::vector<CastableBase*> global_decls);
 
   /// Destructor
   ~Module() override;
 
+  /// @returns the ordered global declarations for the translation unit
+  const std::vector<CastableBase*>& GlobalDeclarations() const {
+    return global_declarations_;
+  }
+
   /// Add a global variable to the Builder
   /// @param var the variable to add
   void AddGlobalVariable(ast::Variable* var) {
     global_variables_.push_back(var);
+    global_declarations_.push_back(var);
   }
 
   /// @returns the global variables for the translation unit
@@ -64,6 +66,7 @@ class Module : public Castable<Module, Node> {
   /// @param type the constructed type to add
   void AddConstructedType(type::Type* type) {
     constructed_types_.push_back(type);
+    global_declarations_.push_back(type);
   }
 
   /// @returns the constructed types in the translation unit
@@ -73,7 +76,10 @@ class Module : public Castable<Module, Node> {
 
   /// Add a function to the Builder
   /// @param func the function to add
-  void AddFunction(ast::Function* func) { functions_.push_back(func); }
+  void AddFunction(ast::Function* func) {
+    functions_.push_back(func);
+    global_declarations_.push_back(func);
+  }
 
   /// @returns the functions declared in the translation unit
   const FunctionList& Functions() const { return functions_; }
@@ -102,6 +108,7 @@ class Module : public Castable<Module, Node> {
   std::string to_str(const semantic::Info& sem) const;
 
  private:
+  std::vector<CastableBase*> global_declarations_;
   std::vector<type::Type*> constructed_types_;
   FunctionList functions_;
   VariableList global_variables_;

src/program.cc

@@ -57,8 +57,7 @@ Program::Program(ProgramBuilder&& builder) {
   ast_nodes_ = std::move(builder.ASTNodes());
   sem_nodes_ = std::move(builder.SemNodes());
   ast_ = ast_nodes_.Create<ast::Module>(
-      Source{}, builder.AST().ConstructedTypes(), builder.AST().Functions(),
-      builder.AST().GlobalVariables());
+      Source{}, std::move(builder.AST().GlobalDeclarations()));
   sem_ = std::move(builder.Sem());
   symbols_ = std::move(builder.Symbols());
   diagnostics_.add(std::move(builder.Diagnostics()));

src/program_builder.cc

@@ -60,8 +60,7 @@ ProgramBuilder ProgramBuilder::Wrap(const Program* program) {
   ProgramBuilder builder;
   builder.types_ = type::Manager::Wrap(program->Types());
   builder.ast_ = builder.create<ast::Module>(
-      program->AST().source(), program->AST().ConstructedTypes(),
-      program->AST().Functions(), program->AST().GlobalVariables());
+      program->AST().source(), program->AST().GlobalDeclarations());
   builder.sem_ = semantic::Info::Wrap(program->Sem());
   builder.symbols_ = program->Symbols();
   builder.diagnostics_ = program->Diagnostics();