|  | // Copyright 2020 The Tint Authors. | 
|  | // | 
|  | // Licensed under the Apache License, Version 2.0 (the "License"); | 
|  | // you may not use this file except in compliance with the License. | 
|  | // You may obtain a copy of the License at | 
|  | // | 
|  | //     http://www.apache.org/licenses/LICENSE-2.0 | 
|  | // | 
|  | // Unless required by applicable law or agreed to in writing, software | 
|  | // distributed under the License is distributed on an "AS IS" BASIS, | 
|  | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
|  | // See the License for the specific language governing permissions and | 
|  | // limitations under the License. | 
|  |  | 
|  | #include "src/tint/resolver/resolver.h" | 
|  |  | 
|  | #include <algorithm> | 
|  | #include <cmath> | 
|  | #include <iomanip> | 
|  | #include <limits> | 
|  | #include <utility> | 
|  |  | 
|  | #include "src/tint/ast/alias.h" | 
|  | #include "src/tint/ast/array.h" | 
|  | #include "src/tint/ast/assignment_statement.h" | 
|  | #include "src/tint/ast/bitcast_expression.h" | 
|  | #include "src/tint/ast/break_statement.h" | 
|  | #include "src/tint/ast/call_statement.h" | 
|  | #include "src/tint/ast/continue_statement.h" | 
|  | #include "src/tint/ast/depth_texture.h" | 
|  | #include "src/tint/ast/disable_validation_attribute.h" | 
|  | #include "src/tint/ast/discard_statement.h" | 
|  | #include "src/tint/ast/fallthrough_statement.h" | 
|  | #include "src/tint/ast/for_loop_statement.h" | 
|  | #include "src/tint/ast/id_attribute.h" | 
|  | #include "src/tint/ast/if_statement.h" | 
|  | #include "src/tint/ast/internal_attribute.h" | 
|  | #include "src/tint/ast/interpolate_attribute.h" | 
|  | #include "src/tint/ast/loop_statement.h" | 
|  | #include "src/tint/ast/matrix.h" | 
|  | #include "src/tint/ast/pointer.h" | 
|  | #include "src/tint/ast/return_statement.h" | 
|  | #include "src/tint/ast/sampled_texture.h" | 
|  | #include "src/tint/ast/sampler.h" | 
|  | #include "src/tint/ast/storage_texture.h" | 
|  | #include "src/tint/ast/switch_statement.h" | 
|  | #include "src/tint/ast/traverse_expressions.h" | 
|  | #include "src/tint/ast/type_name.h" | 
|  | #include "src/tint/ast/unary_op_expression.h" | 
|  | #include "src/tint/ast/variable_decl_statement.h" | 
|  | #include "src/tint/ast/vector.h" | 
|  | #include "src/tint/ast/while_statement.h" | 
|  | #include "src/tint/ast/workgroup_attribute.h" | 
|  | #include "src/tint/resolver/uniformity.h" | 
|  | #include "src/tint/sem/abstract_float.h" | 
|  | #include "src/tint/sem/abstract_int.h" | 
|  | #include "src/tint/sem/array.h" | 
|  | #include "src/tint/sem/atomic.h" | 
|  | #include "src/tint/sem/call.h" | 
|  | #include "src/tint/sem/depth_multisampled_texture.h" | 
|  | #include "src/tint/sem/depth_texture.h" | 
|  | #include "src/tint/sem/for_loop_statement.h" | 
|  | #include "src/tint/sem/function.h" | 
|  | #include "src/tint/sem/if_statement.h" | 
|  | #include "src/tint/sem/index_accessor_expression.h" | 
|  | #include "src/tint/sem/loop_statement.h" | 
|  | #include "src/tint/sem/materialize.h" | 
|  | #include "src/tint/sem/member_accessor_expression.h" | 
|  | #include "src/tint/sem/module.h" | 
|  | #include "src/tint/sem/multisampled_texture.h" | 
|  | #include "src/tint/sem/pointer.h" | 
|  | #include "src/tint/sem/reference.h" | 
|  | #include "src/tint/sem/sampled_texture.h" | 
|  | #include "src/tint/sem/sampler.h" | 
|  | #include "src/tint/sem/statement.h" | 
|  | #include "src/tint/sem/storage_texture.h" | 
|  | #include "src/tint/sem/struct.h" | 
|  | #include "src/tint/sem/switch_statement.h" | 
|  | #include "src/tint/sem/type_constructor.h" | 
|  | #include "src/tint/sem/type_conversion.h" | 
|  | #include "src/tint/sem/variable.h" | 
|  | #include "src/tint/sem/while_statement.h" | 
|  | #include "src/tint/utils/defer.h" | 
|  | #include "src/tint/utils/math.h" | 
|  | #include "src/tint/utils/reverse.h" | 
|  | #include "src/tint/utils/scoped_assignment.h" | 
|  | #include "src/tint/utils/transform.h" | 
|  |  | 
|  | namespace tint::resolver { | 
|  |  | 
|  | Resolver::Resolver(ProgramBuilder* builder) | 
|  | : builder_(builder), | 
|  | diagnostics_(builder->Diagnostics()), | 
|  | intrinsic_table_(IntrinsicTable::Create(*builder)), | 
|  | sem_(builder, dependencies_), | 
|  | validator_(builder, sem_) {} | 
|  |  | 
|  | Resolver::~Resolver() = default; | 
|  |  | 
|  | bool Resolver::Resolve() { | 
|  | if (builder_->Diagnostics().contains_errors()) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | if (!DependencyGraph::Build(builder_->AST(), builder_->Symbols(), builder_->Diagnostics(), | 
|  | dependencies_)) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | bool result = ResolveInternal(); | 
|  |  | 
|  | if (!result && !diagnostics_.contains_errors()) { | 
|  | TINT_ICE(Resolver, diagnostics_) << "resolving failed, but no error was raised"; | 
|  | return false; | 
|  | } | 
|  |  | 
|  | // Create the semantic module | 
|  | builder_->Sem().SetModule(builder_->create<sem::Module>( | 
|  | std::move(dependencies_.ordered_globals), std::move(enabled_extensions_))); | 
|  |  | 
|  | return result; | 
|  | } | 
|  |  | 
|  | bool Resolver::ResolveInternal() { | 
|  | Mark(&builder_->AST()); | 
|  |  | 
|  | // Process all module-scope declarations in dependency order. | 
|  | for (auto* decl : dependencies_.ordered_globals) { | 
|  | Mark(decl); | 
|  | if (!Switch<bool>( | 
|  | decl,  // | 
|  | [&](const ast::Enable* e) { return Enable(e); }, | 
|  | [&](const ast::TypeDecl* td) { return TypeDecl(td); }, | 
|  | [&](const ast::Function* func) { return Function(func); }, | 
|  | [&](const ast::Variable* var) { return GlobalVariable(var); }, | 
|  | [&](Default) { | 
|  | TINT_UNREACHABLE(Resolver, diagnostics_) | 
|  | << "unhandled global declaration: " << decl->TypeInfo().name; | 
|  | return false; | 
|  | })) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  |  | 
|  | AllocateOverridableConstantIds(); | 
|  |  | 
|  | SetShadows(); | 
|  |  | 
|  | if (!validator_.PipelineStages(entry_points_)) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | if (!enabled_extensions_.contains(ast::Extension::kChromiumDisableUniformityAnalysis)) { | 
|  | if (!AnalyzeUniformity(builder_, dependencies_)) { | 
|  | // TODO(jrprice): Reject programs that fail uniformity analysis. | 
|  | } | 
|  | } | 
|  |  | 
|  | bool result = true; | 
|  | for (auto* node : builder_->ASTNodes().Objects()) { | 
|  | if (marked_.count(node) == 0) { | 
|  | TINT_ICE(Resolver, diagnostics_) | 
|  | << "AST node '" << node->TypeInfo().name << "' was not reached by the resolver\n" | 
|  | << "At: " << node->source << "\n" | 
|  | << "Pointer: " << node; | 
|  | result = false; | 
|  | } | 
|  | } | 
|  |  | 
|  | return result; | 
|  | } | 
|  |  | 
|  | sem::Type* Resolver::Type(const ast::Type* ty) { | 
|  | Mark(ty); | 
|  | auto* s = Switch( | 
|  | ty,  // | 
|  | [&](const ast::Void*) { return builder_->create<sem::Void>(); }, | 
|  | [&](const ast::Bool*) { return builder_->create<sem::Bool>(); }, | 
|  | [&](const ast::I32*) { return builder_->create<sem::I32>(); }, | 
|  | [&](const ast::U32*) { return builder_->create<sem::U32>(); }, | 
|  | [&](const ast::F16* t) -> sem::F16* { | 
|  | // Validate if f16 type is allowed. | 
|  | if (!enabled_extensions_.contains(ast::Extension::kF16)) { | 
|  | AddError("f16 used without 'f16' extension enabled", t->source); | 
|  | return nullptr; | 
|  | } | 
|  | return builder_->create<sem::F16>(); | 
|  | }, | 
|  | [&](const ast::F32*) { return builder_->create<sem::F32>(); }, | 
|  | [&](const ast::Vector* t) -> sem::Vector* { | 
|  | if (!t->type) { | 
|  | AddError("missing vector element type", t->source.End()); | 
|  | return nullptr; | 
|  | } | 
|  | if (auto* el = Type(t->type)) { | 
|  | if (auto* vector = builder_->create<sem::Vector>(el, t->width)) { | 
|  | if (validator_.Vector(vector, t->source)) { | 
|  | return vector; | 
|  | } | 
|  | } | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::Matrix* t) -> sem::Matrix* { | 
|  | if (!t->type) { | 
|  | AddError("missing matrix element type", t->source.End()); | 
|  | return nullptr; | 
|  | } | 
|  | if (auto* el = Type(t->type)) { | 
|  | if (auto* column_type = builder_->create<sem::Vector>(el, t->rows)) { | 
|  | if (auto* matrix = builder_->create<sem::Matrix>(column_type, t->columns)) { | 
|  | if (validator_.Matrix(matrix, t->source)) { | 
|  | return matrix; | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::Array* t) { return Array(t); }, | 
|  | [&](const ast::Atomic* t) -> sem::Atomic* { | 
|  | if (auto* el = Type(t->type)) { | 
|  | auto* a = builder_->create<sem::Atomic>(el); | 
|  | if (!validator_.Atomic(t, a)) { | 
|  | return nullptr; | 
|  | } | 
|  | return a; | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::Pointer* t) -> sem::Pointer* { | 
|  | if (auto* el = Type(t->type)) { | 
|  | auto access = t->access; | 
|  | if (access == ast::kUndefined) { | 
|  | access = DefaultAccessForStorageClass(t->storage_class); | 
|  | } | 
|  | return builder_->create<sem::Pointer>(el, t->storage_class, access); | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::Sampler* t) { return builder_->create<sem::Sampler>(t->kind); }, | 
|  | [&](const ast::SampledTexture* t) -> sem::SampledTexture* { | 
|  | if (auto* el = Type(t->type)) { | 
|  | auto* sem = builder_->create<sem::SampledTexture>(t->dim, el); | 
|  | if (!validator_.SampledTexture(sem, t->source)) { | 
|  | return nullptr; | 
|  | } | 
|  | return sem; | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::MultisampledTexture* t) -> sem::MultisampledTexture* { | 
|  | if (auto* el = Type(t->type)) { | 
|  | auto* sem = builder_->create<sem::MultisampledTexture>(t->dim, el); | 
|  | if (!validator_.MultisampledTexture(sem, t->source)) { | 
|  | return nullptr; | 
|  | } | 
|  | return sem; | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::DepthTexture* t) { return builder_->create<sem::DepthTexture>(t->dim); }, | 
|  | [&](const ast::DepthMultisampledTexture* t) { | 
|  | return builder_->create<sem::DepthMultisampledTexture>(t->dim); | 
|  | }, | 
|  | [&](const ast::StorageTexture* t) -> sem::StorageTexture* { | 
|  | if (auto* el = Type(t->type)) { | 
|  | if (!validator_.StorageTexture(t)) { | 
|  | return nullptr; | 
|  | } | 
|  | return builder_->create<sem::StorageTexture>(t->dim, t->format, t->access, el); | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::ExternalTexture*) { return builder_->create<sem::ExternalTexture>(); }, | 
|  | [&](Default) { | 
|  | auto* resolved = sem_.ResolvedSymbol(ty); | 
|  | return Switch( | 
|  | resolved,  // | 
|  | [&](sem::Type* type) { return type; }, | 
|  | [&](sem::Variable* var) { | 
|  | auto name = builder_->Symbols().NameFor(var->Declaration()->symbol); | 
|  | AddError("cannot use variable '" + name + "' as type", ty->source); | 
|  | AddNote("'" + name + "' declared here", var->Declaration()->source); | 
|  | return nullptr; | 
|  | }, | 
|  | [&](sem::Function* func) { | 
|  | auto name = builder_->Symbols().NameFor(func->Declaration()->symbol); | 
|  | AddError("cannot use function '" + name + "' as type", ty->source); | 
|  | AddNote("'" + name + "' declared here", func->Declaration()->source); | 
|  | return nullptr; | 
|  | }, | 
|  | [&](Default) { | 
|  | if (auto* tn = ty->As<ast::TypeName>()) { | 
|  | if (IsBuiltin(tn->name)) { | 
|  | auto name = builder_->Symbols().NameFor(tn->name); | 
|  | AddError("cannot use builtin '" + name + "' as type", ty->source); | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  | TINT_UNREACHABLE(Resolver, diagnostics_) | 
|  | << "Unhandled resolved type '" | 
|  | << (resolved ? resolved->TypeInfo().name : "<null>") | 
|  | << "' resolved from ast::Type '" << ty->TypeInfo().name << "'"; | 
|  | return nullptr; | 
|  | }); | 
|  | }); | 
|  |  | 
|  | if (s) { | 
|  | builder_->Sem().Add(ty, s); | 
|  | } | 
|  | return s; | 
|  | } | 
|  |  | 
|  | sem::Variable* Resolver::Variable(const ast::Variable* v, bool is_global) { | 
|  | return Switch( | 
|  | v,  // | 
|  | [&](const ast::Var* var) { return Var(var, is_global); }, | 
|  | [&](const ast::Let* let) { return Let(let, is_global); }, | 
|  | [&](const ast::Override* override) { return Override(override); }, | 
|  | [&](const ast::Const* const_) { return Const(const_, is_global); }, | 
|  | [&](Default) { | 
|  | TINT_ICE(Resolver, diagnostics_) | 
|  | << "Resolver::GlobalVariable() called with a unknown variable type: " | 
|  | << v->TypeInfo().name; | 
|  | return nullptr; | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Variable* Resolver::Let(const ast::Let* v, bool is_global) { | 
|  | const sem::Type* ty = nullptr; | 
|  |  | 
|  | // If the variable has a declared type, resolve it. | 
|  | if (v->type) { | 
|  | ty = Type(v->type); | 
|  | if (!ty) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (!v->constructor) { | 
|  | AddError("'let' declaration must have an initializer", v->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto* rhs = Materialize(Expression(v->constructor), ty); | 
|  | if (!rhs) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // If the variable has no declared type, infer it from the RHS | 
|  | if (!ty) { | 
|  | ty = rhs->Type()->UnwrapRef();  // Implicit load of RHS | 
|  | } | 
|  |  | 
|  | if (rhs && !validator_.VariableInitializer(v, ast::StorageClass::kNone, ty, rhs)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (!ApplyStorageClassUsageToType(ast::StorageClass::kNone, const_cast<sem::Type*>(ty), | 
|  | v->source)) { | 
|  | AddNote("while instantiating 'let' " + builder_->Symbols().NameFor(v->symbol), v->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | sem::Variable* sem = nullptr; | 
|  | if (is_global) { | 
|  | sem = builder_->create<sem::GlobalVariable>( | 
|  | v, ty, ast::StorageClass::kNone, ast::Access::kUndefined, /* constant_value */ nullptr, | 
|  | sem::BindingPoint{}); | 
|  | } else { | 
|  | sem = builder_->create<sem::LocalVariable>(v, ty, ast::StorageClass::kNone, | 
|  | ast::Access::kUndefined, current_statement_, | 
|  | /* constant_value */ nullptr); | 
|  | } | 
|  |  | 
|  | sem->SetConstructor(rhs); | 
|  | builder_->Sem().Add(v, sem); | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | sem::Variable* Resolver::Override(const ast::Override* v) { | 
|  | const sem::Type* ty = nullptr; | 
|  |  | 
|  | // If the variable has a declared type, resolve it. | 
|  | if (v->type) { | 
|  | ty = Type(v->type); | 
|  | if (!ty) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | const sem::Expression* rhs = nullptr; | 
|  |  | 
|  | // Does the variable have a constructor? | 
|  | if (v->constructor) { | 
|  | rhs = Materialize(Expression(v->constructor), ty); | 
|  | if (!rhs) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // If the variable has no declared type, infer it from the RHS | 
|  | if (!ty) { | 
|  | ty = rhs->Type()->UnwrapRef();  // Implicit load of RHS | 
|  | } | 
|  | } else if (!ty) { | 
|  | AddError("override declaration requires a type or initializer", v->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (rhs && !validator_.VariableInitializer(v, ast::StorageClass::kNone, ty, rhs)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (!ApplyStorageClassUsageToType(ast::StorageClass::kNone, const_cast<sem::Type*>(ty), | 
|  | v->source)) { | 
|  | AddNote("while instantiating 'override' " + builder_->Symbols().NameFor(v->symbol), | 
|  | v->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto* sem = builder_->create<sem::GlobalVariable>( | 
|  | v, ty, ast::StorageClass::kNone, ast::Access::kUndefined, /* constant_value */ nullptr, | 
|  | sem::BindingPoint{}); | 
|  |  | 
|  | if (auto* id = ast::GetAttribute<ast::IdAttribute>(v->attributes)) { | 
|  | sem->SetConstantId(static_cast<uint16_t>(id->value)); | 
|  | } | 
|  |  | 
|  | sem->SetConstructor(rhs); | 
|  | builder_->Sem().Add(v, sem); | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | sem::Variable* Resolver::Const(const ast::Const* c, bool is_global) { | 
|  | const sem::Type* ty = nullptr; | 
|  |  | 
|  | // If the variable has a declared type, resolve it. | 
|  | if (c->type) { | 
|  | ty = Type(c->type); | 
|  | if (!ty) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (!c->constructor) { | 
|  | AddError("'const' declaration must have an initializer", c->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | const auto* rhs = Expression(c->constructor); | 
|  | if (!rhs) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (ty) { | 
|  | // If an explicit type was specified, materialize to that type | 
|  | rhs = Materialize(rhs, ty); | 
|  | if (!rhs) { | 
|  | return nullptr; | 
|  | } | 
|  | } else { | 
|  | // If no type was specified, infer it from the RHS | 
|  | ty = rhs->Type(); | 
|  | } | 
|  |  | 
|  | const auto value = rhs->ConstantValue(); | 
|  | if (!value) { | 
|  | AddError("'const' initializer must be constant expression", c->constructor->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (!validator_.VariableInitializer(c, ast::StorageClass::kNone, ty, rhs)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (!ApplyStorageClassUsageToType(ast::StorageClass::kNone, const_cast<sem::Type*>(ty), | 
|  | c->source)) { | 
|  | AddNote("while instantiating 'const' " + builder_->Symbols().NameFor(c->symbol), c->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto* sem = is_global ? static_cast<sem::Variable*>(builder_->create<sem::GlobalVariable>( | 
|  | c, ty, ast::StorageClass::kNone, ast::Access::kUndefined, value, | 
|  | sem::BindingPoint{})) | 
|  | : static_cast<sem::Variable*>(builder_->create<sem::LocalVariable>( | 
|  | c, ty, ast::StorageClass::kNone, ast::Access::kUndefined, | 
|  | current_statement_, value)); | 
|  |  | 
|  | sem->SetConstructor(rhs); | 
|  | builder_->Sem().Add(c, sem); | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | sem::Variable* Resolver::Var(const ast::Var* var, bool is_global) { | 
|  | const sem::Type* storage_ty = nullptr; | 
|  |  | 
|  | // If the variable has a declared type, resolve it. | 
|  | if (auto* ty = var->type) { | 
|  | storage_ty = Type(ty); | 
|  | if (!storage_ty) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | const sem::Expression* rhs = nullptr; | 
|  |  | 
|  | // Does the variable have a constructor? | 
|  | if (var->constructor) { | 
|  | rhs = Materialize(Expression(var->constructor), storage_ty); | 
|  | if (!rhs) { | 
|  | return nullptr; | 
|  | } | 
|  | // If the variable has no declared type, infer it from the RHS | 
|  | if (!storage_ty) { | 
|  | storage_ty = rhs->Type()->UnwrapRef();  // Implicit load of RHS | 
|  | } | 
|  | } | 
|  |  | 
|  | if (!storage_ty) { | 
|  | AddError("var declaration requires a type or initializer", var->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto storage_class = var->declared_storage_class; | 
|  | if (storage_class == ast::StorageClass::kNone) { | 
|  | // No declared storage class. Infer from usage / type. | 
|  | if (!is_global) { | 
|  | storage_class = ast::StorageClass::kFunction; | 
|  | } else if (storage_ty->UnwrapRef()->is_handle()) { | 
|  | // https://gpuweb.github.io/gpuweb/wgsl/#module-scope-variables | 
|  | // If the store type is a texture type or a sampler type, then the | 
|  | // variable declaration must not have a storage class attribute. The | 
|  | // storage class will always be handle. | 
|  | storage_class = ast::StorageClass::kHandle; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (!is_global && storage_class != ast::StorageClass::kFunction && | 
|  | validator_.IsValidationEnabled(var->attributes, | 
|  | ast::DisabledValidation::kIgnoreStorageClass)) { | 
|  | AddError("function-scope 'var' declaration must use 'function' storage class", var->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto access = var->declared_access; | 
|  | if (access == ast::Access::kUndefined) { | 
|  | access = DefaultAccessForStorageClass(storage_class); | 
|  | } | 
|  |  | 
|  | if (rhs && !validator_.VariableInitializer(var, storage_class, storage_ty, rhs)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto* var_ty = builder_->create<sem::Reference>(storage_ty, storage_class, access); | 
|  |  | 
|  | if (!ApplyStorageClassUsageToType(storage_class, var_ty, var->source)) { | 
|  | AddNote("while instantiating 'var' " + builder_->Symbols().NameFor(var->symbol), | 
|  | var->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | sem::Variable* sem = nullptr; | 
|  | if (is_global) { | 
|  | sem::BindingPoint binding_point; | 
|  | if (auto bp = var->BindingPoint()) { | 
|  | binding_point = {bp.group->value, bp.binding->value}; | 
|  | } | 
|  | sem = builder_->create<sem::GlobalVariable>(var, var_ty, storage_class, access, | 
|  | /* constant_value */ nullptr, binding_point); | 
|  |  | 
|  | } else { | 
|  | sem = builder_->create<sem::LocalVariable>( | 
|  | var, var_ty, storage_class, access, current_statement_, /* constant_value */ nullptr); | 
|  | } | 
|  |  | 
|  | sem->SetConstructor(rhs); | 
|  | builder_->Sem().Add(var, sem); | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | sem::Parameter* Resolver::Parameter(const ast::Parameter* param, uint32_t index) { | 
|  | auto add_note = [&] { | 
|  | AddNote("while instantiating parameter " + builder_->Symbols().NameFor(param->symbol), | 
|  | param->source); | 
|  | }; | 
|  |  | 
|  | for (auto* attr : param->attributes) { | 
|  | Mark(attr); | 
|  | } | 
|  | if (!validator_.NoDuplicateAttributes(param->attributes)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | sem::Type* ty = Type(param->type); | 
|  | if (!ty) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (!ApplyStorageClassUsageToType(ast::StorageClass::kNone, ty, param->source)) { | 
|  | add_note(); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (auto* ptr = ty->As<sem::Pointer>()) { | 
|  | // For MSL, we push module-scope variables into the entry point as pointer | 
|  | // parameters, so we also need to handle their store type. | 
|  | if (!ApplyStorageClassUsageToType( | 
|  | ptr->StorageClass(), const_cast<sem::Type*>(ptr->StoreType()), param->source)) { | 
|  | add_note(); | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | auto* sem = builder_->create<sem::Parameter>(param, index, ty, ast::StorageClass::kNone, | 
|  | ast::Access::kUndefined); | 
|  | builder_->Sem().Add(param, sem); | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | ast::Access Resolver::DefaultAccessForStorageClass(ast::StorageClass storage_class) { | 
|  | // https://gpuweb.github.io/gpuweb/wgsl/#storage-class | 
|  | switch (storage_class) { | 
|  | case ast::StorageClass::kStorage: | 
|  | case ast::StorageClass::kUniform: | 
|  | case ast::StorageClass::kHandle: | 
|  | return ast::Access::kRead; | 
|  | default: | 
|  | break; | 
|  | } | 
|  | return ast::Access::kReadWrite; | 
|  | } | 
|  |  | 
|  | void Resolver::AllocateOverridableConstantIds() { | 
|  | // The next pipeline constant ID to try to allocate. | 
|  | uint16_t next_constant_id = 0; | 
|  |  | 
|  | // Allocate constant IDs in global declaration order, so that they are | 
|  | // deterministic. | 
|  | // TODO(crbug.com/tint/1192): If a transform changes the order or removes an | 
|  | // unused constant, the allocation may change on the next Resolver pass. | 
|  | for (auto* decl : builder_->AST().GlobalDeclarations()) { | 
|  | auto* override = decl->As<ast::Override>(); | 
|  | if (!override) { | 
|  | continue; | 
|  | } | 
|  |  | 
|  | uint16_t constant_id; | 
|  | if (auto* id_attr = ast::GetAttribute<ast::IdAttribute>(override->attributes)) { | 
|  | constant_id = static_cast<uint16_t>(id_attr->value); | 
|  | } else { | 
|  | // No ID was specified, so allocate the next available ID. | 
|  | constant_id = next_constant_id; | 
|  | while (constant_ids_.count(constant_id)) { | 
|  | if (constant_id == UINT16_MAX) { | 
|  | TINT_ICE(Resolver, builder_->Diagnostics()) | 
|  | << "no more pipeline constant IDs available"; | 
|  | return; | 
|  | } | 
|  | constant_id++; | 
|  | } | 
|  | next_constant_id = constant_id + 1; | 
|  | } | 
|  |  | 
|  | auto* sem = sem_.Get<sem::GlobalVariable>(override); | 
|  | const_cast<sem::GlobalVariable*>(sem)->SetConstantId(constant_id); | 
|  | } | 
|  | } | 
|  |  | 
|  | void Resolver::SetShadows() { | 
|  | for (auto it : dependencies_.shadows) { | 
|  | Switch( | 
|  | sem_.Get(it.first),  // | 
|  | [&](sem::LocalVariable* local) { local->SetShadows(sem_.Get(it.second)); }, | 
|  | [&](sem::Parameter* param) { param->SetShadows(sem_.Get(it.second)); }); | 
|  | } | 
|  | } | 
|  |  | 
|  | sem::GlobalVariable* Resolver::GlobalVariable(const ast::Variable* v) { | 
|  | auto* sem = As<sem::GlobalVariable>(Variable(v, /* is_global */ true)); | 
|  | if (!sem) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | for (auto* attr : v->attributes) { | 
|  | Mark(attr); | 
|  |  | 
|  | if (auto* id_attr = attr->As<ast::IdAttribute>()) { | 
|  | // Track the constant IDs that are specified in the shader. | 
|  | constant_ids_.emplace(id_attr->value, sem); | 
|  | } | 
|  | } | 
|  |  | 
|  | if (!validator_.NoDuplicateAttributes(v->attributes)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (!validator_.GlobalVariable(sem, constant_ids_, atomic_composite_info_)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // TODO(bclayton): Call this at the end of resolve on all uniform and storage | 
|  | // referenced structs | 
|  | if (!validator_.StorageClassLayout(sem, valid_type_storage_layouts_)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | sem::Function* Resolver::Function(const ast::Function* decl) { | 
|  | uint32_t parameter_index = 0; | 
|  | std::unordered_map<Symbol, Source> parameter_names; | 
|  | std::vector<sem::Parameter*> parameters; | 
|  |  | 
|  | // Resolve all the parameters | 
|  | for (auto* param : decl->params) { | 
|  | Mark(param); | 
|  |  | 
|  | {  // Check the parameter name is unique for the function | 
|  | auto emplaced = parameter_names.emplace(param->symbol, param->source); | 
|  | if (!emplaced.second) { | 
|  | auto name = builder_->Symbols().NameFor(param->symbol); | 
|  | AddError("redefinition of parameter '" + name + "'", param->source); | 
|  | AddNote("previous definition is here", emplaced.first->second); | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | auto* p = Parameter(param, parameter_index++); | 
|  | if (!p) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (!validator_.Parameter(decl, p)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | parameters.emplace_back(p); | 
|  |  | 
|  | auto* p_ty = const_cast<sem::Type*>(p->Type()); | 
|  | if (auto* str = p_ty->As<sem::Struct>()) { | 
|  | switch (decl->PipelineStage()) { | 
|  | case ast::PipelineStage::kVertex: | 
|  | str->AddUsage(sem::PipelineStageUsage::kVertexInput); | 
|  | break; | 
|  | case ast::PipelineStage::kFragment: | 
|  | str->AddUsage(sem::PipelineStageUsage::kFragmentInput); | 
|  | break; | 
|  | case ast::PipelineStage::kCompute: | 
|  | str->AddUsage(sem::PipelineStageUsage::kComputeInput); | 
|  | break; | 
|  | case ast::PipelineStage::kNone: | 
|  | break; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | // Resolve the return type | 
|  | sem::Type* return_type = nullptr; | 
|  | if (auto* ty = decl->return_type) { | 
|  | return_type = Type(ty); | 
|  | if (!return_type) { | 
|  | return nullptr; | 
|  | } | 
|  | } else { | 
|  | return_type = builder_->create<sem::Void>(); | 
|  | } | 
|  |  | 
|  | if (auto* str = return_type->As<sem::Struct>()) { | 
|  | if (!ApplyStorageClassUsageToType(ast::StorageClass::kNone, str, decl->source)) { | 
|  | AddNote( | 
|  | "while instantiating return type for " + builder_->Symbols().NameFor(decl->symbol), | 
|  | decl->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | switch (decl->PipelineStage()) { | 
|  | case ast::PipelineStage::kVertex: | 
|  | str->AddUsage(sem::PipelineStageUsage::kVertexOutput); | 
|  | break; | 
|  | case ast::PipelineStage::kFragment: | 
|  | str->AddUsage(sem::PipelineStageUsage::kFragmentOutput); | 
|  | break; | 
|  | case ast::PipelineStage::kCompute: | 
|  | str->AddUsage(sem::PipelineStageUsage::kComputeOutput); | 
|  | break; | 
|  | case ast::PipelineStage::kNone: | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | auto* func = builder_->create<sem::Function>(decl, return_type, parameters); | 
|  | builder_->Sem().Add(decl, func); | 
|  |  | 
|  | TINT_SCOPED_ASSIGNMENT(current_function_, func); | 
|  |  | 
|  | if (!WorkgroupSize(decl)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (decl->IsEntryPoint()) { | 
|  | entry_points_.emplace_back(func); | 
|  | } | 
|  |  | 
|  | if (decl->body) { | 
|  | Mark(decl->body); | 
|  | if (current_compound_statement_) { | 
|  | TINT_ICE(Resolver, diagnostics_) | 
|  | << "Resolver::Function() called with a current compound statement"; | 
|  | return nullptr; | 
|  | } | 
|  | auto* body = StatementScope(decl->body, builder_->create<sem::FunctionBlockStatement>(func), | 
|  | [&] { return Statements(decl->body->statements); }); | 
|  | if (!body) { | 
|  | return nullptr; | 
|  | } | 
|  | func->Behaviors() = body->Behaviors(); | 
|  | if (func->Behaviors().Contains(sem::Behavior::kReturn)) { | 
|  | // https://www.w3.org/TR/WGSL/#behaviors-rules | 
|  | // We assign a behavior to each function: it is its body’s behavior | 
|  | // (treating the body as a regular statement), with any "Return" replaced | 
|  | // by "Next". | 
|  | func->Behaviors().Remove(sem::Behavior::kReturn); | 
|  | func->Behaviors().Add(sem::Behavior::kNext); | 
|  | } | 
|  | } | 
|  |  | 
|  | for (auto* attr : decl->attributes) { | 
|  | Mark(attr); | 
|  | } | 
|  | if (!validator_.NoDuplicateAttributes(decl->attributes)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | for (auto* attr : decl->return_type_attributes) { | 
|  | Mark(attr); | 
|  | } | 
|  | if (!validator_.NoDuplicateAttributes(decl->return_type_attributes)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto stage = current_function_ ? current_function_->Declaration()->PipelineStage() | 
|  | : ast::PipelineStage::kNone; | 
|  | if (!validator_.Function(func, stage)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // If this is an entry point, mark all transitively called functions as being | 
|  | // used by this entry point. | 
|  | if (decl->IsEntryPoint()) { | 
|  | for (auto* f : func->TransitivelyCalledFunctions()) { | 
|  | const_cast<sem::Function*>(f)->AddAncestorEntryPoint(func); | 
|  | } | 
|  | } | 
|  |  | 
|  | return func; | 
|  | } | 
|  |  | 
|  | bool Resolver::WorkgroupSize(const ast::Function* func) { | 
|  | // Set work-group size defaults. | 
|  | sem::WorkgroupSize ws; | 
|  | for (size_t i = 0; i < 3; i++) { | 
|  | ws[i].value = 1; | 
|  | ws[i].overridable_const = nullptr; | 
|  | } | 
|  |  | 
|  | auto* attr = ast::GetAttribute<ast::WorkgroupAttribute>(func->attributes); | 
|  | if (!attr) { | 
|  | return true; | 
|  | } | 
|  |  | 
|  | auto values = attr->Values(); | 
|  | std::array<const sem::Expression*, 3> args = {}; | 
|  | std::array<const sem::Type*, 3> arg_tys = {}; | 
|  | size_t arg_count = 0; | 
|  |  | 
|  | constexpr const char* kErrBadExpr = | 
|  | "workgroup_size argument must be either a literal, constant, or overridable of type " | 
|  | "abstract-integer, i32 or u32"; | 
|  |  | 
|  | for (size_t i = 0; i < 3; i++) { | 
|  | // Each argument to this attribute can either be a literal, an identifier for a module-scope | 
|  | // constants, or nullptr if not specified. | 
|  | auto* value = values[i]; | 
|  | if (!value) { | 
|  | break; | 
|  | } | 
|  | const auto* expr = Expression(value); | 
|  | if (!expr) { | 
|  | return false; | 
|  | } | 
|  | auto* ty = expr->Type(); | 
|  | if (!ty->IsAnyOf<sem::I32, sem::U32, sem::AbstractInt>()) { | 
|  | AddError(kErrBadExpr, value->source); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | args[i] = expr; | 
|  | arg_tys[i] = ty; | 
|  | arg_count++; | 
|  | } | 
|  |  | 
|  | auto* common_ty = sem::Type::Common(arg_tys.data(), arg_count); | 
|  | if (!common_ty) { | 
|  | AddError("workgroup_size arguments must be of the same type, either i32 or u32", | 
|  | attr->source); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | // If all arguments are abstract-integers, then materialize to i32. | 
|  | if (common_ty->Is<sem::AbstractInt>()) { | 
|  | common_ty = builder_->create<sem::I32>(); | 
|  | } | 
|  |  | 
|  | for (size_t i = 0; i < arg_count; i++) { | 
|  | auto* materialized = Materialize(args[i], common_ty); | 
|  | if (!materialized) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | const sem::Constant* value = nullptr; | 
|  |  | 
|  | if (auto* user = args[i]->As<sem::VariableUser>()) { | 
|  | // We have an variable of a module-scope constant. | 
|  | auto* decl = user->Variable()->Declaration(); | 
|  | if (!decl->IsAnyOf<ast::Const, ast::Override>()) { | 
|  | AddError(kErrBadExpr, values[i]->source); | 
|  | return false; | 
|  | } | 
|  | // Capture the constant if it is pipeline-overridable. | 
|  | if (decl->Is<ast::Override>()) { | 
|  | ws[i].overridable_const = decl; | 
|  | } | 
|  |  | 
|  | if (decl->constructor) { | 
|  | value = sem_.Get(decl->constructor)->ConstantValue(); | 
|  | } else { | 
|  | // No constructor means this value must be overriden by the user. | 
|  | ws[i].value = 0; | 
|  | continue; | 
|  | } | 
|  | } else if (values[i]->Is<ast::LiteralExpression>()) { | 
|  | value = materialized->ConstantValue(); | 
|  | } else { | 
|  | AddError(kErrBadExpr, values[i]->source); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | if (!value) { | 
|  | TINT_ICE(Resolver, diagnostics_) | 
|  | << "could not resolve constant workgroup_size constant value"; | 
|  | continue; | 
|  | } | 
|  | // validator_.Validate and set the default value for this dimension. | 
|  | if (value->As<AInt>() < 1) { | 
|  | AddError("workgroup_size argument must be at least 1", values[i]->source); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | ws[i].value = value->As<uint32_t>(); | 
|  | } | 
|  |  | 
|  | current_function_->SetWorkgroupSize(std::move(ws)); | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool Resolver::Statements(const ast::StatementList& stmts) { | 
|  | sem::Behaviors behaviors{sem::Behavior::kNext}; | 
|  |  | 
|  | bool reachable = true; | 
|  | for (auto* stmt : stmts) { | 
|  | Mark(stmt); | 
|  | auto* sem = Statement(stmt); | 
|  | if (!sem) { | 
|  | return false; | 
|  | } | 
|  | // s1 s2:(B1∖{Next}) ∪ B2 | 
|  | sem->SetIsReachable(reachable); | 
|  | if (reachable) { | 
|  | behaviors = (behaviors - sem::Behavior::kNext) + sem->Behaviors(); | 
|  | } | 
|  | reachable = reachable && sem->Behaviors().Contains(sem::Behavior::kNext); | 
|  | } | 
|  |  | 
|  | current_statement_->Behaviors() = behaviors; | 
|  |  | 
|  | if (!validator_.Statements(stmts)) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | return true; | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::Statement(const ast::Statement* stmt) { | 
|  | return Switch( | 
|  | stmt, | 
|  | // Compound statements. These create their own sem::CompoundStatement | 
|  | // bindings. | 
|  | [&](const ast::BlockStatement* b) { return BlockStatement(b); }, | 
|  | [&](const ast::ForLoopStatement* l) { return ForLoopStatement(l); }, | 
|  | [&](const ast::LoopStatement* l) { return LoopStatement(l); }, | 
|  | [&](const ast::WhileStatement* w) { return WhileStatement(w); }, | 
|  | [&](const ast::IfStatement* i) { return IfStatement(i); }, | 
|  | [&](const ast::SwitchStatement* s) { return SwitchStatement(s); }, | 
|  |  | 
|  | // Non-Compound statements | 
|  | [&](const ast::AssignmentStatement* a) { return AssignmentStatement(a); }, | 
|  | [&](const ast::BreakStatement* b) { return BreakStatement(b); }, | 
|  | [&](const ast::CallStatement* c) { return CallStatement(c); }, | 
|  | [&](const ast::CompoundAssignmentStatement* c) { return CompoundAssignmentStatement(c); }, | 
|  | [&](const ast::ContinueStatement* c) { return ContinueStatement(c); }, | 
|  | [&](const ast::DiscardStatement* d) { return DiscardStatement(d); }, | 
|  | [&](const ast::FallthroughStatement* f) { return FallthroughStatement(f); }, | 
|  | [&](const ast::IncrementDecrementStatement* i) { return IncrementDecrementStatement(i); }, | 
|  | [&](const ast::ReturnStatement* r) { return ReturnStatement(r); }, | 
|  | [&](const ast::VariableDeclStatement* v) { return VariableDeclStatement(v); }, | 
|  |  | 
|  | // Error cases | 
|  | [&](const ast::CaseStatement*) { | 
|  | AddError("case statement can only be used inside a switch statement", stmt->source); | 
|  | return nullptr; | 
|  | }, | 
|  | [&](Default) { | 
|  | AddError("unknown statement type: " + std::string(stmt->TypeInfo().name), stmt->source); | 
|  | return nullptr; | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::CaseStatement* Resolver::CaseStatement(const ast::CaseStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::CaseStatement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | sem->Selectors().reserve(stmt->selectors.size()); | 
|  | for (auto* sel : stmt->selectors) { | 
|  | auto* expr = Expression(sel); | 
|  | if (!expr) { | 
|  | return false; | 
|  | } | 
|  | sem->Selectors().emplace_back(expr); | 
|  | } | 
|  | Mark(stmt->body); | 
|  | auto* body = BlockStatement(stmt->body); | 
|  | if (!body) { | 
|  | return false; | 
|  | } | 
|  | sem->SetBlock(body); | 
|  | sem->Behaviors() = body->Behaviors(); | 
|  | return true; | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::IfStatement* Resolver::IfStatement(const ast::IfStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::IfStatement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | auto* cond = Expression(stmt->condition); | 
|  | if (!cond) { | 
|  | return false; | 
|  | } | 
|  | sem->SetCondition(cond); | 
|  | sem->Behaviors() = cond->Behaviors(); | 
|  | sem->Behaviors().Remove(sem::Behavior::kNext); | 
|  |  | 
|  | Mark(stmt->body); | 
|  | auto* body = builder_->create<sem::BlockStatement>(stmt->body, current_compound_statement_, | 
|  | current_function_); | 
|  | if (!StatementScope(stmt->body, body, [&] { return Statements(stmt->body->statements); })) { | 
|  | return false; | 
|  | } | 
|  | sem->Behaviors().Add(body->Behaviors()); | 
|  |  | 
|  | if (stmt->else_statement) { | 
|  | Mark(stmt->else_statement); | 
|  | auto* else_sem = Statement(stmt->else_statement); | 
|  | if (!else_sem) { | 
|  | return false; | 
|  | } | 
|  | sem->Behaviors().Add(else_sem->Behaviors()); | 
|  | } else { | 
|  | // https://www.w3.org/TR/WGSL/#behaviors-rules | 
|  | // if statements without an else branch are treated as if they had an | 
|  | // empty else branch (which adds Next to their behavior) | 
|  | sem->Behaviors().Add(sem::Behavior::kNext); | 
|  | } | 
|  |  | 
|  | return validator_.IfStatement(sem); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::BlockStatement* Resolver::BlockStatement(const ast::BlockStatement* stmt) { | 
|  | auto* sem = builder_->create<sem::BlockStatement>( | 
|  | stmt->As<ast::BlockStatement>(), current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { return Statements(stmt->statements); }); | 
|  | } | 
|  |  | 
|  | sem::LoopStatement* Resolver::LoopStatement(const ast::LoopStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::LoopStatement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | Mark(stmt->body); | 
|  |  | 
|  | auto* body = builder_->create<sem::LoopBlockStatement>( | 
|  | stmt->body, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt->body, body, [&] { | 
|  | if (!Statements(stmt->body->statements)) { | 
|  | return false; | 
|  | } | 
|  | auto& behaviors = sem->Behaviors(); | 
|  | behaviors = body->Behaviors(); | 
|  |  | 
|  | if (stmt->continuing) { | 
|  | Mark(stmt->continuing); | 
|  | auto* continuing = StatementScope( | 
|  | stmt->continuing, | 
|  | builder_->create<sem::LoopContinuingBlockStatement>( | 
|  | stmt->continuing, current_compound_statement_, current_function_), | 
|  | [&] { return Statements(stmt->continuing->statements); }); | 
|  | if (!continuing) { | 
|  | return false; | 
|  | } | 
|  | behaviors.Add(continuing->Behaviors()); | 
|  | } | 
|  |  | 
|  | if (behaviors.Contains(sem::Behavior::kBreak)) {  // Does the loop exit? | 
|  | behaviors.Add(sem::Behavior::kNext); | 
|  | } else { | 
|  | behaviors.Remove(sem::Behavior::kNext); | 
|  | } | 
|  | behaviors.Remove(sem::Behavior::kBreak, sem::Behavior::kContinue); | 
|  |  | 
|  | return validator_.LoopStatement(sem); | 
|  | }); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::ForLoopStatement* Resolver::ForLoopStatement(const ast::ForLoopStatement* stmt) { | 
|  | auto* sem = builder_->create<sem::ForLoopStatement>(stmt, current_compound_statement_, | 
|  | current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | auto& behaviors = sem->Behaviors(); | 
|  | if (auto* initializer = stmt->initializer) { | 
|  | Mark(initializer); | 
|  | auto* init = Statement(initializer); | 
|  | if (!init) { | 
|  | return false; | 
|  | } | 
|  | behaviors.Add(init->Behaviors()); | 
|  | } | 
|  |  | 
|  | if (auto* cond_expr = stmt->condition) { | 
|  | auto* cond = Expression(cond_expr); | 
|  | if (!cond) { | 
|  | return false; | 
|  | } | 
|  | sem->SetCondition(cond); | 
|  | behaviors.Add(cond->Behaviors()); | 
|  | } | 
|  |  | 
|  | if (auto* continuing = stmt->continuing) { | 
|  | Mark(continuing); | 
|  | auto* cont = Statement(continuing); | 
|  | if (!cont) { | 
|  | return false; | 
|  | } | 
|  | behaviors.Add(cont->Behaviors()); | 
|  | } | 
|  |  | 
|  | Mark(stmt->body); | 
|  |  | 
|  | auto* body = builder_->create<sem::LoopBlockStatement>( | 
|  | stmt->body, current_compound_statement_, current_function_); | 
|  | if (!StatementScope(stmt->body, body, [&] { return Statements(stmt->body->statements); })) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | behaviors.Add(body->Behaviors()); | 
|  | if (stmt->condition || behaviors.Contains(sem::Behavior::kBreak)) {  // Does the loop exit? | 
|  | behaviors.Add(sem::Behavior::kNext); | 
|  | } else { | 
|  | behaviors.Remove(sem::Behavior::kNext); | 
|  | } | 
|  | behaviors.Remove(sem::Behavior::kBreak, sem::Behavior::kContinue); | 
|  |  | 
|  | return validator_.ForLoopStatement(sem); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::WhileStatement* Resolver::WhileStatement(const ast::WhileStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::WhileStatement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | auto& behaviors = sem->Behaviors(); | 
|  |  | 
|  | auto* cond = Expression(stmt->condition); | 
|  | if (!cond) { | 
|  | return false; | 
|  | } | 
|  | sem->SetCondition(cond); | 
|  | behaviors.Add(cond->Behaviors()); | 
|  |  | 
|  | Mark(stmt->body); | 
|  |  | 
|  | auto* body = builder_->create<sem::LoopBlockStatement>( | 
|  | stmt->body, current_compound_statement_, current_function_); | 
|  | if (!StatementScope(stmt->body, body, [&] { return Statements(stmt->body->statements); })) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | behaviors.Add(body->Behaviors()); | 
|  | // Always consider the while as having a 'next' behaviour because it has | 
|  | // a condition. We don't check if the condition will terminate but it isn't | 
|  | // valid to have an infinite loop in a WGSL program, so a non-terminating | 
|  | // condition is already an invalid program. | 
|  | behaviors.Add(sem::Behavior::kNext); | 
|  | behaviors.Remove(sem::Behavior::kBreak, sem::Behavior::kContinue); | 
|  |  | 
|  | return validator_.WhileStatement(sem); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Expression* Resolver::Expression(const ast::Expression* root) { | 
|  | std::vector<const ast::Expression*> sorted; | 
|  | constexpr size_t kMaxExpressionDepth = 512U; | 
|  | bool failed = false; | 
|  | if (!ast::TraverseExpressions<ast::TraverseOrder::RightToLeft>( | 
|  | root, diagnostics_, [&](const ast::Expression* expr, size_t depth) { | 
|  | if (depth > kMaxExpressionDepth) { | 
|  | AddError( | 
|  | "reached max expression depth of " + std::to_string(kMaxExpressionDepth), | 
|  | expr->source); | 
|  | failed = true; | 
|  | return ast::TraverseAction::Stop; | 
|  | } | 
|  | if (!Mark(expr)) { | 
|  | failed = true; | 
|  | return ast::TraverseAction::Stop; | 
|  | } | 
|  | sorted.emplace_back(expr); | 
|  | return ast::TraverseAction::Descend; | 
|  | })) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (failed) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | for (auto* expr : utils::Reverse(sorted)) { | 
|  | auto* sem_expr = Switch( | 
|  | expr, | 
|  | [&](const ast::IndexAccessorExpression* array) -> sem::Expression* { | 
|  | return IndexAccessor(array); | 
|  | }, | 
|  | [&](const ast::BinaryExpression* bin_op) -> sem::Expression* { return Binary(bin_op); }, | 
|  | [&](const ast::BitcastExpression* bitcast) -> sem::Expression* { | 
|  | return Bitcast(bitcast); | 
|  | }, | 
|  | [&](const ast::CallExpression* call) -> sem::Expression* { return Call(call); }, | 
|  | [&](const ast::IdentifierExpression* ident) -> sem::Expression* { | 
|  | return Identifier(ident); | 
|  | }, | 
|  | [&](const ast::LiteralExpression* literal) -> sem::Expression* { | 
|  | return Literal(literal); | 
|  | }, | 
|  | [&](const ast::MemberAccessorExpression* member) -> sem::Expression* { | 
|  | return MemberAccessor(member); | 
|  | }, | 
|  | [&](const ast::UnaryOpExpression* unary) -> sem::Expression* { return UnaryOp(unary); }, | 
|  | [&](const ast::PhonyExpression*) -> sem::Expression* { | 
|  | return builder_->create<sem::Expression>(expr, builder_->create<sem::Void>(), | 
|  | current_statement_, | 
|  | /* constant_value */ nullptr, | 
|  | /* has_side_effects */ false); | 
|  | }, | 
|  | [&](Default) { | 
|  | TINT_ICE(Resolver, diagnostics_) | 
|  | << "unhandled expression type: " << expr->TypeInfo().name; | 
|  | return nullptr; | 
|  | }); | 
|  | if (!sem_expr) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | builder_->Sem().Add(expr, sem_expr); | 
|  | if (expr == root) { | 
|  | return sem_expr; | 
|  | } | 
|  | } | 
|  |  | 
|  | TINT_ICE(Resolver, diagnostics_) << "Expression() did not find root node"; | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | const sem::Expression* Resolver::Materialize(const sem::Expression* expr, | 
|  | const sem::Type* target_type /* = nullptr */) { | 
|  | if (!expr) { | 
|  | return nullptr;  // Allow for Materialize(Expression(blah)) | 
|  | } | 
|  |  | 
|  | // Helper for actually creating the the materialize node, performing the constant cast, updating | 
|  | // the ast -> sem binding, and performing validation. | 
|  | auto materialize = [&](const sem::Type* target_ty) -> sem::Materialize* { | 
|  | auto* src_ty = expr->Type(); | 
|  | auto* decl = expr->Declaration(); | 
|  | if (!validator_.Materialize(target_ty, src_ty, decl->source)) { | 
|  | return nullptr; | 
|  | } | 
|  | auto expr_val = expr->ConstantValue(); | 
|  | if (!expr_val) { | 
|  | TINT_ICE(Resolver, builder_->Diagnostics()) | 
|  | << decl->source << "Materialize(" << decl->TypeInfo().name | 
|  | << ") called on expression with no constant value"; | 
|  | return nullptr; | 
|  | } | 
|  | auto materialized_val = ConvertValue(expr_val, target_ty, decl->source); | 
|  | if (!materialized_val) { | 
|  | // ConvertValue() has already failed and raised an diagnostic error. | 
|  | return nullptr; | 
|  | } | 
|  | if (!materialized_val.Get()) { | 
|  | TINT_ICE(Resolver, builder_->Diagnostics()) | 
|  | << decl->source << "ConvertValue(" << builder_->FriendlyName(expr_val->Type()) | 
|  | << " -> " << builder_->FriendlyName(target_ty) << ") returned invalid value"; | 
|  | return nullptr; | 
|  | } | 
|  | auto* m = | 
|  | builder_->create<sem::Materialize>(expr, current_statement_, materialized_val.Get()); | 
|  | m->Behaviors() = expr->Behaviors(); | 
|  | builder_->Sem().Replace(decl, m); | 
|  | return m; | 
|  | }; | 
|  |  | 
|  | // Helpers for constructing semantic types | 
|  | auto i32 = [&] { return builder_->create<sem::I32>(); }; | 
|  | auto f32 = [&] { return builder_->create<sem::F32>(); }; | 
|  | auto i32v = [&](uint32_t width) { return builder_->create<sem::Vector>(i32(), width); }; | 
|  | auto f32v = [&](uint32_t width) { return builder_->create<sem::Vector>(f32(), width); }; | 
|  | auto f32m = [&](uint32_t columns, uint32_t rows) { | 
|  | return builder_->create<sem::Matrix>(f32v(rows), columns); | 
|  | }; | 
|  |  | 
|  | // Type dispatch based on the expression type | 
|  | return Switch<sem::Expression*>( | 
|  | expr->Type(),  // | 
|  | [&](const sem::AbstractInt*) { return materialize(target_type ? target_type : i32()); }, | 
|  | [&](const sem::AbstractFloat*) { return materialize(target_type ? target_type : f32()); }, | 
|  | [&](const sem::Vector* v) { | 
|  | return Switch( | 
|  | v->type(),  // | 
|  | [&](const sem::AbstractInt*) { | 
|  | return materialize(target_type ? target_type : i32v(v->Width())); | 
|  | }, | 
|  | [&](const sem::AbstractFloat*) { | 
|  | return materialize(target_type ? target_type : f32v(v->Width())); | 
|  | }, | 
|  | [&](Default) { return expr; }); | 
|  | }, | 
|  | [&](const sem::Matrix* m) { | 
|  | return Switch( | 
|  | m->type(),  // | 
|  | [&](const sem::AbstractFloat*) { | 
|  | return materialize(target_type ? target_type : f32m(m->columns(), m->rows())); | 
|  | }, | 
|  | [&](Default) { return expr; }); | 
|  | }, | 
|  | [&](Default) { return expr; }); | 
|  | } | 
|  |  | 
|  | bool Resolver::MaterializeArguments(std::vector<const sem::Expression*>& args, | 
|  | const sem::CallTarget* target) { | 
|  | for (size_t i = 0, n = std::min(args.size(), target->Parameters().size()); i < n; i++) { | 
|  | const auto* param_ty = target->Parameters()[i]->Type(); | 
|  | if (ShouldMaterializeArgument(param_ty)) { | 
|  | auto* materialized = Materialize(args[i], param_ty); | 
|  | if (!materialized) { | 
|  | return false; | 
|  | } | 
|  | args[i] = materialized; | 
|  | } | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool Resolver::ShouldMaterializeArgument(const sem::Type* parameter_ty) const { | 
|  | const auto* param_el_ty = sem::Type::ElementOf(parameter_ty); | 
|  | return param_el_ty && !param_el_ty->Is<sem::AbstractNumeric>(); | 
|  | } | 
|  |  | 
|  | sem::Expression* Resolver::IndexAccessor(const ast::IndexAccessorExpression* expr) { | 
|  | auto* idx = Materialize(sem_.Get(expr->index)); | 
|  | if (!idx) { | 
|  | return nullptr; | 
|  | } | 
|  | auto* obj = sem_.Get(expr->object); | 
|  | auto* obj_raw_ty = obj->Type(); | 
|  | auto* obj_ty = obj_raw_ty->UnwrapRef(); | 
|  | auto* ty = Switch( | 
|  | obj_ty,  // | 
|  | [&](const sem::Array* arr) { return arr->ElemType(); }, | 
|  | [&](const sem::Vector* vec) { return vec->type(); }, | 
|  | [&](const sem::Matrix* mat) { | 
|  | return builder_->create<sem::Vector>(mat->type(), mat->rows()); | 
|  | }, | 
|  | [&](Default) { | 
|  | AddError("cannot index type '" + sem_.TypeNameOf(obj_ty) + "'", expr->source); | 
|  | return nullptr; | 
|  | }); | 
|  | if (ty == nullptr) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto* idx_ty = idx->Type()->UnwrapRef(); | 
|  | if (!idx_ty->IsAnyOf<sem::I32, sem::U32>()) { | 
|  | AddError("index must be of type 'i32' or 'u32', found: '" + sem_.TypeNameOf(idx_ty) + "'", | 
|  | idx->Declaration()->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // If we're extracting from a reference, we return a reference. | 
|  | if (auto* ref = obj_raw_ty->As<sem::Reference>()) { | 
|  | ty = builder_->create<sem::Reference>(ty, ref->StorageClass(), ref->Access()); | 
|  | } | 
|  |  | 
|  | auto val = EvaluateIndexValue(obj, idx); | 
|  | bool has_side_effects = idx->HasSideEffects() || obj->HasSideEffects(); | 
|  | auto* sem = builder_->create<sem::IndexAccessorExpression>( | 
|  | expr, ty, obj, idx, current_statement_, std::move(val), has_side_effects, | 
|  | obj->SourceVariable()); | 
|  | sem->Behaviors() = idx->Behaviors() + obj->Behaviors(); | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | sem::Expression* Resolver::Bitcast(const ast::BitcastExpression* expr) { | 
|  | auto* inner = Materialize(sem_.Get(expr->expr)); | 
|  | if (!inner) { | 
|  | return nullptr; | 
|  | } | 
|  | auto* ty = Type(expr->type); | 
|  | if (!ty) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto val = EvaluateBitcastValue(inner, ty); | 
|  | auto* sem = builder_->create<sem::Expression>(expr, ty, current_statement_, std::move(val), | 
|  | inner->HasSideEffects()); | 
|  |  | 
|  | sem->Behaviors() = inner->Behaviors(); | 
|  |  | 
|  | if (!validator_.Bitcast(expr, ty)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | sem::Call* Resolver::Call(const ast::CallExpression* expr) { | 
|  | // A CallExpression can resolve to one of: | 
|  | // * A function call. | 
|  | // * A builtin call. | 
|  | // * A type constructor. | 
|  | // * A type conversion. | 
|  |  | 
|  | // Resolve all of the arguments, their types and the set of behaviors. | 
|  | std::vector<const sem::Expression*> args(expr->args.size()); | 
|  | sem::Behaviors arg_behaviors; | 
|  | for (size_t i = 0; i < expr->args.size(); i++) { | 
|  | auto* arg = sem_.Get(expr->args[i]); | 
|  | if (!arg) { | 
|  | return nullptr; | 
|  | } | 
|  | args[i] = arg; | 
|  | arg_behaviors.Add(arg->Behaviors()); | 
|  | } | 
|  | arg_behaviors.Remove(sem::Behavior::kNext); | 
|  |  | 
|  | // Did any arguments have side effects? | 
|  | bool has_side_effects = | 
|  | std::any_of(args.begin(), args.end(), [](auto* e) { return e->HasSideEffects(); }); | 
|  |  | 
|  | // ct_ctor_or_conv is a helper for building either a sem::TypeConstructor or sem::TypeConversion | 
|  | // call for a CtorConvIntrinsic with an optional template argument type. | 
|  | auto ct_ctor_or_conv = [&](CtorConvIntrinsic ty, const sem::Type* template_arg) -> sem::Call* { | 
|  | auto arg_tys = utils::Transform(args, [](auto* arg) { return arg->Type(); }); | 
|  | auto* call_target = intrinsic_table_->Lookup(ty, template_arg, arg_tys, expr->source); | 
|  | if (!call_target) { | 
|  | return nullptr; | 
|  | } | 
|  | if (!MaterializeArguments(args, call_target)) { | 
|  | return nullptr; | 
|  | } | 
|  | auto val = EvaluateCtorOrConvValue(args, call_target->ReturnType()); | 
|  | return builder_->create<sem::Call>(expr, call_target, std::move(args), current_statement_, | 
|  | val, has_side_effects); | 
|  | }; | 
|  |  | 
|  | // ct_ctor_or_conv is a helper for building either a sem::TypeConstructor or sem::TypeConversion | 
|  | // call for the given semantic type. | 
|  | auto ty_ctor_or_conv = [&](const sem::Type* ty) { | 
|  | return Switch( | 
|  | ty,  // | 
|  | [&](const sem::Vector* v) { | 
|  | return ct_ctor_or_conv(VectorCtorConvIntrinsic(v->Width()), v->type()); | 
|  | }, | 
|  | [&](const sem::Matrix* m) { | 
|  | return ct_ctor_or_conv(MatrixCtorConvIntrinsic(m->columns(), m->rows()), m->type()); | 
|  | }, | 
|  | [&](const sem::I32*) { return ct_ctor_or_conv(CtorConvIntrinsic::kI32, nullptr); }, | 
|  | [&](const sem::U32*) { return ct_ctor_or_conv(CtorConvIntrinsic::kU32, nullptr); }, | 
|  | [&](const sem::F16*) { return ct_ctor_or_conv(CtorConvIntrinsic::kF16, nullptr); }, | 
|  | [&](const sem::F32*) { return ct_ctor_or_conv(CtorConvIntrinsic::kF32, nullptr); }, | 
|  | [&](const sem::Bool*) { return ct_ctor_or_conv(CtorConvIntrinsic::kBool, nullptr); }, | 
|  | [&](const sem::Array* arr) -> sem::Call* { | 
|  | auto* call_target = utils::GetOrCreate( | 
|  | array_ctors_, ArrayConstructorSig{{arr, args.size()}}, | 
|  | [&]() -> sem::TypeConstructor* { | 
|  | sem::ParameterList params(args.size()); | 
|  | for (size_t i = 0; i < args.size(); i++) { | 
|  | params[i] = builder_->create<sem::Parameter>( | 
|  | nullptr,                   // declaration | 
|  | static_cast<uint32_t>(i),  // index | 
|  | arr->ElemType(),           // type | 
|  | ast::StorageClass::kNone,  // storage_class | 
|  | ast::Access::kUndefined);  // access | 
|  | } | 
|  | return builder_->create<sem::TypeConstructor>(arr, std::move(params)); | 
|  | }); | 
|  | if (!MaterializeArguments(args, call_target)) { | 
|  | return nullptr; | 
|  | } | 
|  | auto val = EvaluateCtorOrConvValue(args, arr); | 
|  | return builder_->create<sem::Call>(expr, call_target, std::move(args), | 
|  | current_statement_, val, has_side_effects); | 
|  | }, | 
|  | [&](const sem::Struct* str) -> sem::Call* { | 
|  | auto* call_target = utils::GetOrCreate( | 
|  | struct_ctors_, StructConstructorSig{{str, args.size()}}, | 
|  | [&]() -> sem::TypeConstructor* { | 
|  | sem::ParameterList params(std::min(args.size(), str->Members().size())); | 
|  | for (size_t i = 0, n = params.size(); i < n; i++) { | 
|  | params[i] = builder_->create<sem::Parameter>( | 
|  | nullptr,                    // declaration | 
|  | static_cast<uint32_t>(i),   // index | 
|  | str->Members()[i]->Type(),  // type | 
|  | ast::StorageClass::kNone,   // storage_class | 
|  | ast::Access::kUndefined);   // access | 
|  | } | 
|  | return builder_->create<sem::TypeConstructor>(str, std::move(params)); | 
|  | }); | 
|  | if (!MaterializeArguments(args, call_target)) { | 
|  | return nullptr; | 
|  | } | 
|  | auto val = EvaluateCtorOrConvValue(args, str); | 
|  | return builder_->create<sem::Call>(expr, call_target, std::move(args), | 
|  | current_statement_, std::move(val), | 
|  | has_side_effects); | 
|  | }, | 
|  | [&](Default) { | 
|  | AddError("type is not constructible", expr->source); | 
|  | return nullptr; | 
|  | }); | 
|  | }; | 
|  |  | 
|  | // ast::CallExpression has a target which is either an ast::Type or an ast::IdentifierExpression | 
|  | sem::Call* call = nullptr; | 
|  | if (expr->target.type) { | 
|  | // ast::CallExpression has an ast::Type as the target. | 
|  | // This call is either a type constructor or type conversion. | 
|  | call = Switch( | 
|  | expr->target.type, | 
|  | [&](const ast::Vector* v) -> sem::Call* { | 
|  | Mark(v); | 
|  | // vector element type must be inferred if it was not specified. | 
|  | sem::Type* template_arg = nullptr; | 
|  | if (v->type) { | 
|  | template_arg = Type(v->type); | 
|  | if (!template_arg) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  | if (auto* c = ct_ctor_or_conv(VectorCtorConvIntrinsic(v->width), template_arg)) { | 
|  | builder_->Sem().Add(expr->target.type, c->Target()->ReturnType()); | 
|  | return c; | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::Matrix* m) -> sem::Call* { | 
|  | Mark(m); | 
|  | // matrix element type must be inferred if it was not specified. | 
|  | sem::Type* template_arg = nullptr; | 
|  | if (m->type) { | 
|  | template_arg = Type(m->type); | 
|  | if (!template_arg) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  | if (auto* c = ct_ctor_or_conv(MatrixCtorConvIntrinsic(m->columns, m->rows), | 
|  | template_arg)) { | 
|  | builder_->Sem().Add(expr->target.type, c->Target()->ReturnType()); | 
|  | return c; | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::Type* ast) -> sem::Call* { | 
|  | // Handler for AST types that do not have an optional element type. | 
|  | if (auto* ty = Type(ast)) { | 
|  | return ty_ctor_or_conv(ty); | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](Default) { | 
|  | TINT_ICE(Resolver, diagnostics_) | 
|  | << expr->source << " unhandled CallExpression target:\n" | 
|  | << "type: " | 
|  | << (expr->target.type ? expr->target.type->TypeInfo().name : "<null>"); | 
|  | return nullptr; | 
|  | }); | 
|  | } else { | 
|  | // ast::CallExpression has an ast::IdentifierExpression as the target. | 
|  | // This call is either a function call, builtin call, type constructor or type conversion. | 
|  | auto* ident = expr->target.name; | 
|  | Mark(ident); | 
|  | auto* resolved = sem_.ResolvedSymbol(ident); | 
|  | call = Switch<sem::Call*>( | 
|  | resolved,  // | 
|  | [&](sem::Type* ty) { | 
|  | // A type constructor or conversions. | 
|  | // Note: Unlike the code path where we're resolving the call target from an | 
|  | // ast::Type, all types must already have the element type explicitly specified, so | 
|  | // there's no need to infer element types. | 
|  | return ty_ctor_or_conv(ty); | 
|  | }, | 
|  | [&](sem::Function* func) { | 
|  | return FunctionCall(expr, func, std::move(args), arg_behaviors); | 
|  | }, | 
|  | [&](sem::Variable* var) { | 
|  | auto name = builder_->Symbols().NameFor(var->Declaration()->symbol); | 
|  | AddError("cannot call variable '" + name + "'", ident->source); | 
|  | AddNote("'" + name + "' declared here", var->Declaration()->source); | 
|  | return nullptr; | 
|  | }, | 
|  | [&](Default) -> sem::Call* { | 
|  | auto name = builder_->Symbols().NameFor(ident->symbol); | 
|  | auto builtin_type = sem::ParseBuiltinType(name); | 
|  | if (builtin_type != sem::BuiltinType::kNone) { | 
|  | return BuiltinCall(expr, builtin_type, std::move(args)); | 
|  | } | 
|  |  | 
|  | TINT_ICE(Resolver, diagnostics_) | 
|  | << expr->source << " unhandled CallExpression target:\n" | 
|  | << "resolved: " << (resolved ? resolved->TypeInfo().name : "<null>") << "\n" | 
|  | << "name: " << builder_->Symbols().NameFor(ident->symbol); | 
|  | return nullptr; | 
|  | }); | 
|  | } | 
|  |  | 
|  | if (!call) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | return validator_.Call(call, current_statement_) ? call : nullptr; | 
|  | } | 
|  |  | 
|  | sem::Call* Resolver::BuiltinCall(const ast::CallExpression* expr, | 
|  | sem::BuiltinType builtin_type, | 
|  | std::vector<const sem::Expression*> args) { | 
|  | IntrinsicTable::Builtin builtin; | 
|  | { | 
|  | auto arg_tys = utils::Transform(args, [](auto* arg) { return arg->Type(); }); | 
|  | builtin = intrinsic_table_->Lookup(builtin_type, arg_tys, expr->source); | 
|  | if (!builtin.sem) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (!MaterializeArguments(args, builtin.sem)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (builtin.sem->IsDeprecated()) { | 
|  | AddWarning("use of deprecated builtin", expr->source); | 
|  | } | 
|  |  | 
|  | // If the builtin is @const, and all arguments have constant values, evaluate the builtin now. | 
|  | const sem::Constant* constant = nullptr; | 
|  | if (builtin.const_eval_fn) { | 
|  | std::vector<const sem::Constant*> values(args.size()); | 
|  | bool is_const = true;  // all arguments have constant values | 
|  | for (size_t i = 0; i < values.size(); i++) { | 
|  | if (auto v = args[i]->ConstantValue()) { | 
|  | values[i] = std::move(v); | 
|  | } else { | 
|  | is_const = false; | 
|  | break; | 
|  | } | 
|  | } | 
|  | if (is_const) { | 
|  | constant = builtin.const_eval_fn(*builder_, values.data(), args.size()); | 
|  | } | 
|  | } | 
|  |  | 
|  | bool has_side_effects = | 
|  | builtin.sem->HasSideEffects() || | 
|  | std::any_of(args.begin(), args.end(), [](auto* e) { return e->HasSideEffects(); }); | 
|  | auto* call = builder_->create<sem::Call>(expr, builtin.sem, std::move(args), current_statement_, | 
|  | constant, has_side_effects); | 
|  |  | 
|  | if (current_function_) { | 
|  | current_function_->AddDirectlyCalledBuiltin(builtin.sem); | 
|  | current_function_->AddDirectCall(call); | 
|  | } | 
|  |  | 
|  | if (!validator_.RequiredExtensionForBuiltinFunction(call, enabled_extensions_)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (IsTextureBuiltin(builtin_type)) { | 
|  | if (!validator_.TextureBuiltinFunction(call)) { | 
|  | return nullptr; | 
|  | } | 
|  | CollectTextureSamplerPairs(builtin.sem, call->Arguments()); | 
|  | } | 
|  |  | 
|  | if (!validator_.BuiltinCall(call)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | return call; | 
|  | } | 
|  |  | 
|  | void Resolver::CollectTextureSamplerPairs(const sem::Builtin* builtin, | 
|  | const std::vector<const sem::Expression*>& args) const { | 
|  | // Collect a texture/sampler pair for this builtin. | 
|  | const auto& signature = builtin->Signature(); | 
|  | int texture_index = signature.IndexOf(sem::ParameterUsage::kTexture); | 
|  | if (texture_index == -1) { | 
|  | TINT_ICE(Resolver, diagnostics_) << "texture builtin without texture parameter"; | 
|  | } | 
|  | auto* texture = args[static_cast<size_t>(texture_index)]->As<sem::VariableUser>()->Variable(); | 
|  | if (!texture->Type()->UnwrapRef()->Is<sem::StorageTexture>()) { | 
|  | int sampler_index = signature.IndexOf(sem::ParameterUsage::kSampler); | 
|  | const sem::Variable* sampler = | 
|  | sampler_index != -1 | 
|  | ? args[static_cast<size_t>(sampler_index)]->As<sem::VariableUser>()->Variable() | 
|  | : nullptr; | 
|  | current_function_->AddTextureSamplerPair(texture, sampler); | 
|  | } | 
|  | } | 
|  |  | 
|  | sem::Call* Resolver::FunctionCall(const ast::CallExpression* expr, | 
|  | sem::Function* target, | 
|  | std::vector<const sem::Expression*> args, | 
|  | sem::Behaviors arg_behaviors) { | 
|  | auto sym = expr->target.name->symbol; | 
|  | auto name = builder_->Symbols().NameFor(sym); | 
|  |  | 
|  | if (!MaterializeArguments(args, target)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // TODO(crbug.com/tint/1420): For now, assume all function calls have side | 
|  | // effects. | 
|  | bool has_side_effects = true; | 
|  | auto* call = builder_->create<sem::Call>(expr, target, std::move(args), current_statement_, | 
|  | /* constant_value */ nullptr, has_side_effects); | 
|  |  | 
|  | target->AddCallSite(call); | 
|  |  | 
|  | call->Behaviors() = arg_behaviors + target->Behaviors(); | 
|  |  | 
|  | if (!validator_.FunctionCall(call, current_statement_)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (current_function_) { | 
|  | // Note: Requires called functions to be resolved first. | 
|  | // This is currently guaranteed as functions must be declared before | 
|  | // use. | 
|  | current_function_->AddTransitivelyCalledFunction(target); | 
|  | current_function_->AddDirectCall(call); | 
|  | for (auto* transitive_call : target->TransitivelyCalledFunctions()) { | 
|  | current_function_->AddTransitivelyCalledFunction(transitive_call); | 
|  | } | 
|  |  | 
|  | // We inherit any referenced variables from the callee. | 
|  | for (auto* var : target->TransitivelyReferencedGlobals()) { | 
|  | current_function_->AddTransitivelyReferencedGlobal(var); | 
|  | } | 
|  |  | 
|  | // Note: Validation *must* be performed before calling this method. | 
|  | CollectTextureSamplerPairs(target, call->Arguments()); | 
|  | } | 
|  |  | 
|  | return call; | 
|  | } | 
|  |  | 
|  | void Resolver::CollectTextureSamplerPairs(sem::Function* func, | 
|  | const std::vector<const sem::Expression*>& args) const { | 
|  | // Map all texture/sampler pairs from the target function to the | 
|  | // current function. These can only be global or parameter | 
|  | // variables. Resolve any parameter variables to the corresponding | 
|  | // argument passed to the current function. Leave global variables | 
|  | // as-is. Then add the mapped pair to the current function's list of | 
|  | // texture/sampler pairs. | 
|  | for (sem::VariablePair pair : func->TextureSamplerPairs()) { | 
|  | const sem::Variable* texture = pair.first; | 
|  | const sem::Variable* sampler = pair.second; | 
|  | if (auto* param = texture->As<sem::Parameter>()) { | 
|  | texture = args[param->Index()]->As<sem::VariableUser>()->Variable(); | 
|  | } | 
|  | if (sampler) { | 
|  | if (auto* param = sampler->As<sem::Parameter>()) { | 
|  | sampler = args[param->Index()]->As<sem::VariableUser>()->Variable(); | 
|  | } | 
|  | } | 
|  | current_function_->AddTextureSamplerPair(texture, sampler); | 
|  | } | 
|  | } | 
|  |  | 
|  | sem::Expression* Resolver::Literal(const ast::LiteralExpression* literal) { | 
|  | auto* ty = Switch( | 
|  | literal, | 
|  | [&](const ast::IntLiteralExpression* i) -> sem::Type* { | 
|  | switch (i->suffix) { | 
|  | case ast::IntLiteralExpression::Suffix::kNone: | 
|  | return builder_->create<sem::AbstractInt>(); | 
|  | case ast::IntLiteralExpression::Suffix::kI: | 
|  | return builder_->create<sem::I32>(); | 
|  | case ast::IntLiteralExpression::Suffix::kU: | 
|  | return builder_->create<sem::U32>(); | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::FloatLiteralExpression* f) -> sem::Type* { | 
|  | switch (f->suffix) { | 
|  | case ast::FloatLiteralExpression::Suffix::kNone: | 
|  | return builder_->create<sem::AbstractFloat>(); | 
|  | case ast::FloatLiteralExpression::Suffix::kF: | 
|  | return builder_->create<sem::F32>(); | 
|  | case ast::FloatLiteralExpression::Suffix::kH: | 
|  | return builder_->create<sem::F16>(); | 
|  | } | 
|  | return nullptr; | 
|  | }, | 
|  | [&](const ast::BoolLiteralExpression*) { return builder_->create<sem::Bool>(); }, | 
|  | [&](Default) { return nullptr; }); | 
|  |  | 
|  | if (ty == nullptr) { | 
|  | TINT_UNREACHABLE(Resolver, builder_->Diagnostics()) | 
|  | << "Unhandled literal type: " << literal->TypeInfo().name; | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if ((ty->Is<sem::F16>()) && (!enabled_extensions_.contains(tint::ast::Extension::kF16))) { | 
|  | AddError("f16 literal used without 'f16' extension enabled", literal->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto val = EvaluateLiteralValue(literal, ty); | 
|  | return builder_->create<sem::Expression>(literal, ty, current_statement_, std::move(val), | 
|  | /* has_side_effects */ false); | 
|  | } | 
|  |  | 
|  | sem::Expression* Resolver::Identifier(const ast::IdentifierExpression* expr) { | 
|  | auto symbol = expr->symbol; | 
|  | auto* resolved = sem_.ResolvedSymbol(expr); | 
|  | if (auto* variable = As<sem::Variable>(resolved)) { | 
|  | auto* user = builder_->create<sem::VariableUser>(expr, current_statement_, variable); | 
|  |  | 
|  | if (current_statement_) { | 
|  | // If identifier is part of a loop continuing block, make sure it | 
|  | // doesn't refer to a variable that is bypassed by a continue statement | 
|  | // in the loop's body block. | 
|  | if (auto* continuing_block = | 
|  | current_statement_->FindFirstParent<sem::LoopContinuingBlockStatement>()) { | 
|  | auto* loop_block = continuing_block->FindFirstParent<sem::LoopBlockStatement>(); | 
|  | if (loop_block->FirstContinue()) { | 
|  | auto& decls = loop_block->Decls(); | 
|  | // If our identifier is in loop_block->decls, make sure its index is | 
|  | // less than first_continue | 
|  | auto iter = std::find_if(decls.begin(), decls.end(), | 
|  | [&symbol](auto* v) { return v->symbol == symbol; }); | 
|  | if (iter != decls.end()) { | 
|  | auto var_decl_index = | 
|  | static_cast<size_t>(std::distance(decls.begin(), iter)); | 
|  | if (var_decl_index >= loop_block->NumDeclsAtFirstContinue()) { | 
|  | AddError("continue statement bypasses declaration of '" + | 
|  | builder_->Symbols().NameFor(symbol) + "'", | 
|  | loop_block->FirstContinue()->source); | 
|  | AddNote("identifier '" + builder_->Symbols().NameFor(symbol) + | 
|  | "' declared here", | 
|  | (*iter)->source); | 
|  | AddNote("identifier '" + builder_->Symbols().NameFor(symbol) + | 
|  | "' referenced in continuing block here", | 
|  | expr->source); | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | if (current_function_) { | 
|  | if (auto* global = variable->As<sem::GlobalVariable>()) { | 
|  | current_function_->AddDirectlyReferencedGlobal(global); | 
|  | } | 
|  | } else if (variable->Declaration()->Is<ast::Var>()) { | 
|  | // Use of a module-scope 'var' outside of a function. | 
|  | // Note: The spec is currently vague around the rules here. See | 
|  | // https://github.com/gpuweb/gpuweb/issues/3081. Remove this comment when resolved. | 
|  | std::string desc = "var '" + builder_->Symbols().NameFor(symbol) + "' "; | 
|  | AddError(desc + "cannot not be referenced at module-scope", expr->source); | 
|  | AddNote(desc + "declared here", variable->Declaration()->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | variable->AddUser(user); | 
|  | return user; | 
|  | } | 
|  |  | 
|  | if (Is<sem::Function>(resolved)) { | 
|  | AddError("missing '(' for function call", expr->source.End()); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (IsBuiltin(symbol)) { | 
|  | AddError("missing '(' for builtin call", expr->source.End()); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (resolved->Is<sem::Type>()) { | 
|  | AddError("missing '(' for type constructor or cast", expr->source.End()); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | TINT_ICE(Resolver, diagnostics_) | 
|  | << expr->source << " unresolved identifier:\n" | 
|  | << "resolved: " << (resolved ? resolved->TypeInfo().name : "<null>") << "\n" | 
|  | << "name: " << builder_->Symbols().NameFor(symbol); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | sem::Expression* Resolver::MemberAccessor(const ast::MemberAccessorExpression* expr) { | 
|  | auto* structure = sem_.TypeOf(expr->structure); | 
|  | auto* storage_ty = structure->UnwrapRef(); | 
|  | auto* source_var = sem_.Get(expr->structure)->SourceVariable(); | 
|  |  | 
|  | const sem::Type* ret = nullptr; | 
|  | std::vector<uint32_t> swizzle; | 
|  |  | 
|  | // Object may be a side-effecting expression (e.g. function call). | 
|  | auto* object = sem_.Get(expr->structure); | 
|  | bool has_side_effects = object && object->HasSideEffects(); | 
|  |  | 
|  | if (auto* str = storage_ty->As<sem::Struct>()) { | 
|  | Mark(expr->member); | 
|  | auto symbol = expr->member->symbol; | 
|  |  | 
|  | const sem::StructMember* member = nullptr; | 
|  | for (auto* m : str->Members()) { | 
|  | if (m->Name() == symbol) { | 
|  | ret = m->Type(); | 
|  | member = m; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (ret == nullptr) { | 
|  | AddError("struct member " + builder_->Symbols().NameFor(symbol) + " not found", | 
|  | expr->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // If we're extracting from a reference, we return a reference. | 
|  | if (auto* ref = structure->As<sem::Reference>()) { | 
|  | ret = builder_->create<sem::Reference>(ret, ref->StorageClass(), ref->Access()); | 
|  | } | 
|  |  | 
|  | sem::Constant* val = nullptr;  // TODO(crbug.com/tint/1611): Add structure support. | 
|  | return builder_->create<sem::StructMemberAccess>(expr, ret, current_statement_, val, object, | 
|  | member, has_side_effects, source_var); | 
|  | } | 
|  |  | 
|  | if (auto* vec = storage_ty->As<sem::Vector>()) { | 
|  | Mark(expr->member); | 
|  | std::string s = builder_->Symbols().NameFor(expr->member->symbol); | 
|  | auto size = s.size(); | 
|  | swizzle.reserve(s.size()); | 
|  |  | 
|  | for (auto c : s) { | 
|  | switch (c) { | 
|  | case 'x': | 
|  | case 'r': | 
|  | swizzle.emplace_back(0); | 
|  | break; | 
|  | case 'y': | 
|  | case 'g': | 
|  | swizzle.emplace_back(1); | 
|  | break; | 
|  | case 'z': | 
|  | case 'b': | 
|  | swizzle.emplace_back(2); | 
|  | break; | 
|  | case 'w': | 
|  | case 'a': | 
|  | swizzle.emplace_back(3); | 
|  | break; | 
|  | default: | 
|  | AddError("invalid vector swizzle character", | 
|  | expr->member->source.Begin() + swizzle.size()); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (swizzle.back() >= vec->Width()) { | 
|  | AddError("invalid vector swizzle member", expr->member->source); | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (size < 1 || size > 4) { | 
|  | AddError("invalid vector swizzle size", expr->member->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // All characters are valid, check if they're being mixed | 
|  | auto is_rgba = [](char c) { return c == 'r' || c == 'g' || c == 'b' || c == 'a'; }; | 
|  | auto is_xyzw = [](char c) { return c == 'x' || c == 'y' || c == 'z' || c == 'w'; }; | 
|  | if (!std::all_of(s.begin(), s.end(), is_rgba) && | 
|  | !std::all_of(s.begin(), s.end(), is_xyzw)) { | 
|  | AddError("invalid mixing of vector swizzle characters rgba with xyzw", | 
|  | expr->member->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (size == 1) { | 
|  | // A single element swizzle is just the type of the vector. | 
|  | ret = vec->type(); | 
|  | // If we're extracting from a reference, we return a reference. | 
|  | if (auto* ref = structure->As<sem::Reference>()) { | 
|  | ret = builder_->create<sem::Reference>(ret, ref->StorageClass(), ref->Access()); | 
|  | } | 
|  | } else { | 
|  | // The vector will have a number of components equal to the length of | 
|  | // the swizzle. | 
|  | ret = builder_->create<sem::Vector>(vec->type(), static_cast<uint32_t>(size)); | 
|  | } | 
|  | auto* val = EvaluateSwizzleValue(object, ret, swizzle); | 
|  | return builder_->create<sem::Swizzle>(expr, ret, current_statement_, val, object, | 
|  | std::move(swizzle), has_side_effects, source_var); | 
|  | } | 
|  |  | 
|  | AddError("invalid member accessor expression. Expected vector or struct, got '" + | 
|  | sem_.TypeNameOf(storage_ty) + "'", | 
|  | expr->structure->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | sem::Expression* Resolver::Binary(const ast::BinaryExpression* expr) { | 
|  | const auto* lhs = sem_.Get(expr->lhs); | 
|  | const auto* rhs = sem_.Get(expr->rhs); | 
|  | auto* lhs_ty = lhs->Type()->UnwrapRef(); | 
|  | auto* rhs_ty = rhs->Type()->UnwrapRef(); | 
|  |  | 
|  | auto op = intrinsic_table_->Lookup(expr->op, lhs_ty, rhs_ty, expr->source, false); | 
|  | if (!op.result) { | 
|  | return nullptr; | 
|  | } | 
|  | if (ShouldMaterializeArgument(op.lhs)) { | 
|  | lhs = Materialize(lhs, op.lhs); | 
|  | if (!lhs) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  | if (ShouldMaterializeArgument(op.rhs)) { | 
|  | rhs = Materialize(rhs, op.rhs); | 
|  | if (!rhs) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | auto* val = EvaluateBinaryValue(lhs, rhs, op); | 
|  | bool has_side_effects = lhs->HasSideEffects() || rhs->HasSideEffects(); | 
|  | auto* sem = builder_->create<sem::Expression>(expr, op.result, current_statement_, val, | 
|  | has_side_effects); | 
|  | sem->Behaviors() = lhs->Behaviors() + rhs->Behaviors(); | 
|  |  | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | sem::Expression* Resolver::UnaryOp(const ast::UnaryOpExpression* unary) { | 
|  | const auto* expr = sem_.Get(unary->expr); | 
|  | auto* expr_ty = expr->Type(); | 
|  | if (!expr_ty) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | const sem::Type* ty = nullptr; | 
|  | const sem::Variable* source_var = nullptr; | 
|  | const sem::Constant* val = nullptr; | 
|  |  | 
|  | switch (unary->op) { | 
|  | case ast::UnaryOp::kAddressOf: | 
|  | if (auto* ref = expr_ty->As<sem::Reference>()) { | 
|  | if (ref->StoreType()->UnwrapRef()->is_handle()) { | 
|  | AddError("cannot take the address of expression in handle storage class", | 
|  | unary->expr->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto* array = unary->expr->As<ast::IndexAccessorExpression>(); | 
|  | auto* member = unary->expr->As<ast::MemberAccessorExpression>(); | 
|  | if ((array && sem_.TypeOf(array->object)->UnwrapRef()->Is<sem::Vector>()) || | 
|  | (member && sem_.TypeOf(member->structure)->UnwrapRef()->Is<sem::Vector>())) { | 
|  | AddError("cannot take the address of a vector component", unary->expr->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | ty = builder_->create<sem::Pointer>(ref->StoreType(), ref->StorageClass(), | 
|  | ref->Access()); | 
|  |  | 
|  | source_var = expr->SourceVariable(); | 
|  | } else { | 
|  | AddError("cannot take the address of expression", unary->expr->source); | 
|  | return nullptr; | 
|  | } | 
|  | break; | 
|  |  | 
|  | case ast::UnaryOp::kIndirection: | 
|  | if (auto* ptr = expr_ty->As<sem::Pointer>()) { | 
|  | ty = builder_->create<sem::Reference>(ptr->StoreType(), ptr->StorageClass(), | 
|  | ptr->Access()); | 
|  | source_var = expr->SourceVariable(); | 
|  | } else { | 
|  | AddError("cannot dereference expression of type '" + sem_.TypeNameOf(expr_ty) + "'", | 
|  | unary->expr->source); | 
|  | return nullptr; | 
|  | } | 
|  | break; | 
|  |  | 
|  | default: { | 
|  | auto op = intrinsic_table_->Lookup(unary->op, expr_ty, unary->source); | 
|  | if (!op.result) { | 
|  | return nullptr; | 
|  | } | 
|  | if (ShouldMaterializeArgument(op.parameter)) { | 
|  | expr = Materialize(expr, op.parameter); | 
|  | if (!expr) { | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  | ty = op.result; | 
|  | val = EvaluateUnaryValue(expr, op); | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | auto* sem = builder_->create<sem::Expression>(unary, ty, current_statement_, val, | 
|  | expr->HasSideEffects(), source_var); | 
|  | sem->Behaviors() = expr->Behaviors(); | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | bool Resolver::Enable(const ast::Enable* enable) { | 
|  | enabled_extensions_.add(enable->extension); | 
|  | return true; | 
|  | } | 
|  |  | 
|  | sem::Type* Resolver::TypeDecl(const ast::TypeDecl* named_type) { | 
|  | sem::Type* result = nullptr; | 
|  | if (auto* alias = named_type->As<ast::Alias>()) { | 
|  | result = Alias(alias); | 
|  | } else if (auto* str = named_type->As<ast::Struct>()) { | 
|  | result = Structure(str); | 
|  | } else { | 
|  | TINT_UNREACHABLE(Resolver, diagnostics_) << "Unhandled TypeDecl"; | 
|  | } | 
|  |  | 
|  | if (!result) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | builder_->Sem().Add(named_type, result); | 
|  | return result; | 
|  | } | 
|  |  | 
|  | sem::Array* Resolver::Array(const ast::Array* arr) { | 
|  | auto source = arr->source; | 
|  |  | 
|  | auto* elem_type = Type(arr->type); | 
|  | if (!elem_type) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (!validator_.IsPlain(elem_type)) {  // Check must come before GetDefaultAlignAndSize() | 
|  | AddError(sem_.TypeNameOf(elem_type) + " cannot be used as an element type of an array", | 
|  | source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | uint32_t el_align = elem_type->Align(); | 
|  | uint32_t el_size = elem_type->Size(); | 
|  |  | 
|  | if (!validator_.NoDuplicateAttributes(arr->attributes)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // Look for explicit stride via @stride(n) attribute | 
|  | uint32_t explicit_stride = 0; | 
|  | for (auto* attr : arr->attributes) { | 
|  | Mark(attr); | 
|  | if (auto* sd = attr->As<ast::StrideAttribute>()) { | 
|  | explicit_stride = sd->stride; | 
|  | if (!validator_.ArrayStrideAttribute(sd, el_size, el_align, source)) { | 
|  | return nullptr; | 
|  | } | 
|  | continue; | 
|  | } | 
|  |  | 
|  | AddError("attribute is not valid for array types", attr->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // Calculate implicit stride | 
|  | uint64_t implicit_stride = utils::RoundUp<uint64_t>(el_align, el_size); | 
|  |  | 
|  | uint64_t stride = explicit_stride ? explicit_stride : implicit_stride; | 
|  |  | 
|  | int64_t count = 0;  // sem::Array uses a size of 0 for a runtime-sized array. | 
|  |  | 
|  | // Evaluate the constant array size expression. | 
|  | if (auto* count_expr = arr->count) { | 
|  | const auto* count_sem = Materialize(Expression(count_expr)); | 
|  | if (!count_sem) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto* count_val = count_sem->ConstantValue(); | 
|  | if (!count_val) { | 
|  | AddError("array size must evaluate to a constant integer expression", | 
|  | count_expr->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (auto* ty = count_val->Type(); !ty->is_integer_scalar()) { | 
|  | AddError("array size must evaluate to a constant integer expression, but is type '" + | 
|  | builder_->FriendlyName(ty) + "'", | 
|  | count_expr->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | count = count_val->As<AInt>(); | 
|  | if (count < 1) { | 
|  | AddError("array size (" + std::to_string(count) + ") must be greater than 0", | 
|  | count_expr->source); | 
|  | return nullptr; | 
|  | } | 
|  | } | 
|  |  | 
|  | auto size = std::max<uint64_t>(static_cast<uint32_t>(count), 1u) * stride; | 
|  | if (size > std::numeric_limits<uint32_t>::max()) { | 
|  | std::stringstream msg; | 
|  | msg << "array size (0x" << std::hex << size << ") must not exceed 0xffffffff bytes"; | 
|  | AddError(msg.str(), arr->source); | 
|  | return nullptr; | 
|  | } | 
|  | auto* out = builder_->create<sem::Array>( | 
|  | elem_type, static_cast<uint32_t>(count), el_align, static_cast<uint32_t>(size), | 
|  | static_cast<uint32_t>(stride), static_cast<uint32_t>(implicit_stride)); | 
|  |  | 
|  | if (!validator_.Array(out, source)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | if (elem_type->Is<sem::Atomic>()) { | 
|  | atomic_composite_info_.emplace(out, arr->type->source); | 
|  | } else { | 
|  | auto found = atomic_composite_info_.find(elem_type); | 
|  | if (found != atomic_composite_info_.end()) { | 
|  | atomic_composite_info_.emplace(out, found->second); | 
|  | } | 
|  | } | 
|  |  | 
|  | return out; | 
|  | } | 
|  |  | 
|  | sem::Type* Resolver::Alias(const ast::Alias* alias) { | 
|  | auto* ty = Type(alias->type); | 
|  | if (!ty) { | 
|  | return nullptr; | 
|  | } | 
|  | if (!validator_.Alias(alias)) { | 
|  | return nullptr; | 
|  | } | 
|  | return ty; | 
|  | } | 
|  |  | 
|  | sem::Struct* Resolver::Structure(const ast::Struct* str) { | 
|  | if (!validator_.NoDuplicateAttributes(str->attributes)) { | 
|  | return nullptr; | 
|  | } | 
|  | for (auto* attr : str->attributes) { | 
|  | Mark(attr); | 
|  | } | 
|  |  | 
|  | sem::StructMemberList sem_members; | 
|  | sem_members.reserve(str->members.size()); | 
|  |  | 
|  | // Calculate the effective size and alignment of each field, and the overall | 
|  | // size of the structure. | 
|  | // For size, use the size attribute if provided, otherwise use the default | 
|  | // size for the type. | 
|  | // For alignment, use the alignment attribute if provided, otherwise use the | 
|  | // default alignment for the member type. | 
|  | // Diagnostic errors are raised if a basic rule is violated. | 
|  | // Validation of storage-class rules requires analysing the actual variable | 
|  | // usage of the structure, and so is performed as part of the variable | 
|  | // validation. | 
|  | uint64_t struct_size = 0; | 
|  | uint64_t struct_align = 1; | 
|  | std::unordered_map<Symbol, const ast::StructMember*> member_map; | 
|  |  | 
|  | for (auto* member : str->members) { | 
|  | Mark(member); | 
|  | auto result = member_map.emplace(member->symbol, member); | 
|  | if (!result.second) { | 
|  | AddError("redefinition of '" + builder_->Symbols().NameFor(member->symbol) + "'", | 
|  | member->source); | 
|  | AddNote("previous definition is here", result.first->second->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // Resolve member type | 
|  | auto* type = Type(member->type); | 
|  | if (!type) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | // validator_.Validate member type | 
|  | if (!validator_.IsPlain(type)) { | 
|  | AddError(sem_.TypeNameOf(type) + " cannot be used as the type of a structure member", | 
|  | member->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | uint64_t offset = struct_size; | 
|  | uint64_t align = type->Align(); | 
|  | uint64_t size = type->Size(); | 
|  |  | 
|  | if (!validator_.NoDuplicateAttributes(member->attributes)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | bool has_offset_attr = false; | 
|  | bool has_align_attr = false; | 
|  | bool has_size_attr = false; | 
|  | for (auto* attr : member->attributes) { | 
|  | Mark(attr); | 
|  | if (auto* o = attr->As<ast::StructMemberOffsetAttribute>()) { | 
|  | // Offset attributes are not part of the WGSL spec, but are emitted | 
|  | // by the SPIR-V reader. | 
|  | if (o->offset < struct_size) { | 
|  | AddError("offsets must be in ascending order", o->source); | 
|  | return nullptr; | 
|  | } | 
|  | offset = o->offset; | 
|  | align = 1; | 
|  | has_offset_attr = true; | 
|  | } else if (auto* a = attr->As<ast::StructMemberAlignAttribute>()) { | 
|  | if (a->align <= 0 || !utils::IsPowerOfTwo(a->align)) { | 
|  | AddError("align value must be a positive, power-of-two integer", a->source); | 
|  | return nullptr; | 
|  | } | 
|  | align = a->align; | 
|  | has_align_attr = true; | 
|  | } else if (auto* s = attr->As<ast::StructMemberSizeAttribute>()) { | 
|  | if (s->size < size) { | 
|  | AddError("size must be at least as big as the type's size (" + | 
|  | std::to_string(size) + ")", | 
|  | s->source); | 
|  | return nullptr; | 
|  | } | 
|  | size = s->size; | 
|  | has_size_attr = true; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (has_offset_attr && (has_align_attr || has_size_attr)) { | 
|  | AddError("offset attributes cannot be used with align or size attributes", | 
|  | member->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | offset = utils::RoundUp(align, offset); | 
|  | if (offset > std::numeric_limits<uint32_t>::max()) { | 
|  | std::stringstream msg; | 
|  | msg << "struct member offset (0x" << std::hex << offset << ") must not exceed 0x" | 
|  | << std::hex << std::numeric_limits<uint32_t>::max() << " bytes"; | 
|  | AddError(msg.str(), member->source); | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto* sem_member = builder_->create<sem::StructMember>( | 
|  | member, member->symbol, type, static_cast<uint32_t>(sem_members.size()), | 
|  | static_cast<uint32_t>(offset), static_cast<uint32_t>(align), | 
|  | static_cast<uint32_t>(size)); | 
|  | builder_->Sem().Add(member, sem_member); | 
|  | sem_members.emplace_back(sem_member); | 
|  |  | 
|  | struct_size = offset + size; | 
|  | struct_align = std::max(struct_align, align); | 
|  | } | 
|  |  | 
|  | uint64_t size_no_padding = struct_size; | 
|  | struct_size = utils::RoundUp(struct_align, struct_size); | 
|  |  | 
|  | if (struct_size > std::numeric_limits<uint32_t>::max()) { | 
|  | std::stringstream msg; | 
|  | msg << "struct size (0x" << std::hex << struct_size << ") must not exceed 0xffffffff bytes"; | 
|  | AddError(msg.str(), str->source); | 
|  | return nullptr; | 
|  | } | 
|  | if (struct_align > std::numeric_limits<uint32_t>::max()) { | 
|  | TINT_ICE(Resolver, diagnostics_) << "calculated struct stride exceeds uint32"; | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | auto* out = builder_->create<sem::Struct>( | 
|  | str, str->name, sem_members, static_cast<uint32_t>(struct_align), | 
|  | static_cast<uint32_t>(struct_size), static_cast<uint32_t>(size_no_padding)); | 
|  |  | 
|  | for (size_t i = 0; i < sem_members.size(); i++) { | 
|  | auto* mem_type = sem_members[i]->Type(); | 
|  | if (mem_type->Is<sem::Atomic>()) { | 
|  | atomic_composite_info_.emplace(out, sem_members[i]->Declaration()->source); | 
|  | break; | 
|  | } else { | 
|  | auto found = atomic_composite_info_.find(mem_type); | 
|  | if (found != atomic_composite_info_.end()) { | 
|  | atomic_composite_info_.emplace(out, found->second); | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | const_cast<sem::StructMember*>(sem_members[i])->SetStruct(out); | 
|  | } | 
|  |  | 
|  | auto stage = current_function_ ? current_function_->Declaration()->PipelineStage() | 
|  | : ast::PipelineStage::kNone; | 
|  | if (!validator_.Structure(out, stage)) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | return out; | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::ReturnStatement(const ast::ReturnStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | auto& behaviors = current_statement_->Behaviors(); | 
|  | behaviors = sem::Behavior::kReturn; | 
|  |  | 
|  | const sem::Type* value_ty = nullptr; | 
|  | if (auto* value = stmt->value) { | 
|  | const auto* expr = Expression(value); | 
|  | if (!expr) { | 
|  | return false; | 
|  | } | 
|  | if (auto* ret_ty = current_function_->ReturnType(); !ret_ty->Is<sem::Void>()) { | 
|  | expr = Materialize(expr, ret_ty); | 
|  | if (!expr) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  | behaviors.Add(expr->Behaviors() - sem::Behavior::kNext); | 
|  | value_ty = expr->Type()->UnwrapRef(); | 
|  | } else { | 
|  | value_ty = builder_->create<sem::Void>(); | 
|  | } | 
|  |  | 
|  | // Validate after processing the return value expression so that its type | 
|  | // is available for validation. | 
|  | return validator_.Return(stmt, current_function_->ReturnType(), value_ty, | 
|  | current_statement_); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::SwitchStatement* Resolver::SwitchStatement(const ast::SwitchStatement* stmt) { | 
|  | auto* sem = builder_->create<sem::SwitchStatement>(stmt, current_compound_statement_, | 
|  | current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | auto& behaviors = sem->Behaviors(); | 
|  |  | 
|  | const auto* cond = Expression(stmt->condition); | 
|  | if (!cond) { | 
|  | return false; | 
|  | } | 
|  | behaviors = cond->Behaviors() - sem::Behavior::kNext; | 
|  |  | 
|  | auto* cond_ty = cond->Type()->UnwrapRef(); | 
|  |  | 
|  | utils::UniqueVector<const sem::Type*> types; | 
|  | types.add(cond_ty); | 
|  |  | 
|  | std::vector<sem::CaseStatement*> cases; | 
|  | cases.reserve(stmt->body.size()); | 
|  | for (auto* case_stmt : stmt->body) { | 
|  | Mark(case_stmt); | 
|  | auto* c = CaseStatement(case_stmt); | 
|  | if (!c) { | 
|  | return false; | 
|  | } | 
|  | for (auto* expr : c->Selectors()) { | 
|  | types.add(expr->Type()->UnwrapRef()); | 
|  | } | 
|  | cases.emplace_back(c); | 
|  | behaviors.Add(c->Behaviors()); | 
|  | sem->Cases().emplace_back(c); | 
|  | } | 
|  |  | 
|  | // Determine the common type across all selectors and the switch expression | 
|  | // This must materialize to an integer scalar (non-abstract). | 
|  | auto* common_ty = sem::Type::Common(types.data(), types.size()); | 
|  | if (!common_ty || !common_ty->is_integer_scalar()) { | 
|  | // No common type found or the common type was abstract. | 
|  | // Pick i32 and let validation deal with any mismatches. | 
|  | common_ty = builder_->create<sem::I32>(); | 
|  | } | 
|  | cond = Materialize(cond, common_ty); | 
|  | if (!cond) { | 
|  | return false; | 
|  | } | 
|  | for (auto* c : cases) { | 
|  | for (auto*& sel : c->Selectors()) {  // Note: pointer reference | 
|  | sel = Materialize(sel, common_ty); | 
|  | if (!sel) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | if (behaviors.Contains(sem::Behavior::kBreak)) { | 
|  | behaviors.Add(sem::Behavior::kNext); | 
|  | } | 
|  | behaviors.Remove(sem::Behavior::kBreak, sem::Behavior::kFallthrough); | 
|  |  | 
|  | return validator_.SwitchStatement(stmt); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::VariableDeclStatement(const ast::VariableDeclStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | Mark(stmt->variable); | 
|  |  | 
|  | auto* variable = Variable(stmt->variable, /* is_global */ false); | 
|  | if (!variable) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | for (auto* attr : stmt->variable->attributes) { | 
|  | Mark(attr); | 
|  | if (!attr->Is<ast::InternalAttribute>()) { | 
|  | AddError("attributes are not valid on local variables", attr->source); | 
|  | return false; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (current_block_) {  // Not all statements are inside a block | 
|  | current_block_->AddDecl(stmt->variable); | 
|  | } | 
|  |  | 
|  | if (auto* ctor = variable->Constructor()) { | 
|  | sem->Behaviors() = ctor->Behaviors(); | 
|  | } | 
|  |  | 
|  | return validator_.Variable(variable); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::AssignmentStatement(const ast::AssignmentStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | auto* lhs = Expression(stmt->lhs); | 
|  | if (!lhs) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | const bool is_phony_assignment = stmt->lhs->Is<ast::PhonyExpression>(); | 
|  |  | 
|  | const auto* rhs = Expression(stmt->rhs); | 
|  | if (!rhs) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | if (!is_phony_assignment) { | 
|  | rhs = Materialize(rhs, lhs->Type()->UnwrapRef()); | 
|  | if (!rhs) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  |  | 
|  | auto& behaviors = sem->Behaviors(); | 
|  | behaviors = rhs->Behaviors(); | 
|  | if (!is_phony_assignment) { | 
|  | behaviors.Add(lhs->Behaviors()); | 
|  | } | 
|  |  | 
|  | return validator_.Assignment(stmt, sem_.TypeOf(stmt->rhs)); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::BreakStatement(const ast::BreakStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | sem->Behaviors() = sem::Behavior::kBreak; | 
|  |  | 
|  | return validator_.BreakStatement(sem, current_statement_); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::CallStatement(const ast::CallStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | if (auto* expr = Expression(stmt->expr)) { | 
|  | sem->Behaviors() = expr->Behaviors(); | 
|  | return true; | 
|  | } | 
|  | return false; | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::CompoundAssignmentStatement( | 
|  | const ast::CompoundAssignmentStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | auto* lhs = Expression(stmt->lhs); | 
|  | if (!lhs) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | auto* rhs = Expression(stmt->rhs); | 
|  | if (!rhs) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | sem->Behaviors() = rhs->Behaviors() + lhs->Behaviors(); | 
|  |  | 
|  | auto* lhs_ty = lhs->Type()->UnwrapRef(); | 
|  | auto* rhs_ty = rhs->Type()->UnwrapRef(); | 
|  | auto* ty = intrinsic_table_->Lookup(stmt->op, lhs_ty, rhs_ty, stmt->source, true).result; | 
|  | if (!ty) { | 
|  | return false; | 
|  | } | 
|  | return validator_.Assignment(stmt, ty); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::ContinueStatement(const ast::ContinueStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | sem->Behaviors() = sem::Behavior::kContinue; | 
|  |  | 
|  | // Set if we've hit the first continue statement in our parent loop | 
|  | if (auto* block = sem->FindFirstParent<sem::LoopBlockStatement>()) { | 
|  | if (!block->FirstContinue()) { | 
|  | const_cast<sem::LoopBlockStatement*>(block)->SetFirstContinue( | 
|  | stmt, block->Decls().size()); | 
|  | } | 
|  | } | 
|  |  | 
|  | return validator_.ContinueStatement(sem, current_statement_); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::DiscardStatement(const ast::DiscardStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | sem->Behaviors() = sem::Behavior::kDiscard; | 
|  | current_function_->SetHasDiscard(); | 
|  |  | 
|  | return validator_.DiscardStatement(sem, current_statement_); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::FallthroughStatement(const ast::FallthroughStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | sem->Behaviors() = sem::Behavior::kFallthrough; | 
|  |  | 
|  | return validator_.FallthroughStatement(sem); | 
|  | }); | 
|  | } | 
|  |  | 
|  | sem::Statement* Resolver::IncrementDecrementStatement( | 
|  | const ast::IncrementDecrementStatement* stmt) { | 
|  | auto* sem = | 
|  | builder_->create<sem::Statement>(stmt, current_compound_statement_, current_function_); | 
|  | return StatementScope(stmt, sem, [&] { | 
|  | auto* lhs = Expression(stmt->lhs); | 
|  | if (!lhs) { | 
|  | return false; | 
|  | } | 
|  | sem->Behaviors() = lhs->Behaviors(); | 
|  |  | 
|  | return validator_.IncrementDecrementStatement(stmt); | 
|  | }); | 
|  | } | 
|  |  | 
|  | bool Resolver::ApplyStorageClassUsageToType(ast::StorageClass sc, | 
|  | sem::Type* ty, | 
|  | const Source& usage) { | 
|  | ty = const_cast<sem::Type*>(ty->UnwrapRef()); | 
|  |  | 
|  | if (auto* str = ty->As<sem::Struct>()) { | 
|  | if (str->StorageClassUsage().count(sc)) { | 
|  | return true;  // Already applied | 
|  | } | 
|  |  | 
|  | str->AddUsage(sc); | 
|  |  | 
|  | for (auto* member : str->Members()) { | 
|  | if (!ApplyStorageClassUsageToType(sc, member->Type(), usage)) { | 
|  | std::stringstream err; | 
|  | err << "while analysing structure member " << sem_.TypeNameOf(str) << "." | 
|  | << builder_->Symbols().NameFor(member->Declaration()->symbol); | 
|  | AddNote(err.str(), member->Declaration()->source); | 
|  | return false; | 
|  | } | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | if (auto* arr = ty->As<sem::Array>()) { | 
|  | if (arr->IsRuntimeSized() && sc != ast::StorageClass::kStorage) { | 
|  | AddError( | 
|  | "runtime-sized arrays can only be used in the <storage> storage " | 
|  | "class", | 
|  | usage); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | return ApplyStorageClassUsageToType(sc, const_cast<sem::Type*>(arr->ElemType()), usage); | 
|  | } | 
|  |  | 
|  | if (ast::IsHostShareable(sc) && !validator_.IsHostShareable(ty)) { | 
|  | std::stringstream err; | 
|  | err << "Type '" << sem_.TypeNameOf(ty) << "' cannot be used in storage class '" << sc | 
|  | << "' as it is non-host-shareable"; | 
|  | AddError(err.str(), usage); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | return true; | 
|  | } | 
|  |  | 
|  | template <typename SEM, typename F> | 
|  | SEM* Resolver::StatementScope(const ast::Statement* ast, SEM* sem, F&& callback) { | 
|  | builder_->Sem().Add(ast, sem); | 
|  |  | 
|  | auto* as_compound = As<sem::CompoundStatement, CastFlags::kDontErrorOnImpossibleCast>(sem); | 
|  | auto* as_block = As<sem::BlockStatement, CastFlags::kDontErrorOnImpossibleCast>(sem); | 
|  |  | 
|  | TINT_SCOPED_ASSIGNMENT(current_statement_, sem); | 
|  | TINT_SCOPED_ASSIGNMENT(current_compound_statement_, | 
|  | as_compound ? as_compound : current_compound_statement_); | 
|  | TINT_SCOPED_ASSIGNMENT(current_block_, as_block ? as_block : current_block_); | 
|  |  | 
|  | if (!callback()) { | 
|  | return nullptr; | 
|  | } | 
|  |  | 
|  | return sem; | 
|  | } | 
|  |  | 
|  | bool Resolver::Mark(const ast::Node* node) { | 
|  | if (node == nullptr) { | 
|  | TINT_ICE(Resolver, diagnostics_) << "Resolver::Mark() called with nullptr"; | 
|  | return false; | 
|  | } | 
|  | if (marked_.emplace(node).second) { | 
|  | return true; | 
|  | } | 
|  | TINT_ICE(Resolver, diagnostics_) << "AST node '" << node->TypeInfo().name | 
|  | << "' was encountered twice in the same AST of a Program\n" | 
|  | << "At: " << node->source << "\n" | 
|  | << "Pointer: " << node; | 
|  | return false; | 
|  | } | 
|  |  | 
|  | void Resolver::AddError(const std::string& msg, const Source& source) const { | 
|  | diagnostics_.add_error(diag::System::Resolver, msg, source); | 
|  | } | 
|  |  | 
|  | void Resolver::AddWarning(const std::string& msg, const Source& source) const { | 
|  | diagnostics_.add_warning(diag::System::Resolver, msg, source); | 
|  | } | 
|  |  | 
|  | void Resolver::AddNote(const std::string& msg, const Source& source) const { | 
|  | diagnostics_.add_note(diag::System::Resolver, msg, source); | 
|  | } | 
|  |  | 
|  | bool Resolver::IsBuiltin(Symbol symbol) const { | 
|  | std::string name = builder_->Symbols().NameFor(symbol); | 
|  | return sem::ParseBuiltinType(name) != sem::BuiltinType::kNone; | 
|  | } | 
|  |  | 
|  | }  // namespace tint::resolver |