Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1 | // Copyright 2015 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "src/parsing/parameter-initializer-rewriter.h" |
| 6 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 7 | #include <algorithm> |
| 8 | #include <utility> |
| 9 | #include <vector> |
| 10 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 11 | #include "src/ast/ast.h" |
| 12 | #include "src/ast/ast-expression-visitor.h" |
| 13 | #include "src/ast/scopes.h" |
| 14 | |
| 15 | namespace v8 { |
| 16 | namespace internal { |
| 17 | |
| 18 | namespace { |
| 19 | |
| 20 | |
| 21 | class Rewriter final : public AstExpressionVisitor { |
| 22 | public: |
| 23 | Rewriter(uintptr_t stack_limit, Expression* initializer, Scope* old_scope, |
| 24 | Scope* new_scope) |
| 25 | : AstExpressionVisitor(stack_limit, initializer), |
| 26 | old_scope_(old_scope), |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 27 | new_scope_(new_scope), |
| 28 | old_scope_closure_(old_scope->ClosureScope()), |
| 29 | new_scope_closure_(new_scope->ClosureScope()) {} |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 30 | ~Rewriter(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 31 | |
| 32 | private: |
| 33 | void VisitExpression(Expression* expr) override {} |
| 34 | |
| 35 | void VisitFunctionLiteral(FunctionLiteral* expr) override; |
| 36 | void VisitClassLiteral(ClassLiteral* expr) override; |
| 37 | void VisitVariableProxy(VariableProxy* expr) override; |
| 38 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 39 | void VisitBlock(Block* stmt) override; |
| 40 | void VisitTryCatchStatement(TryCatchStatement* stmt) override; |
| 41 | void VisitWithStatement(WithStatement* stmt) override; |
| 42 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 43 | Scope* old_scope_; |
| 44 | Scope* new_scope_; |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 45 | Scope* old_scope_closure_; |
| 46 | Scope* new_scope_closure_; |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 47 | std::vector<std::pair<Variable*, int>> temps_; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 48 | }; |
| 49 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 50 | struct LessThanSecond { |
| 51 | bool operator()(const std::pair<Variable*, int>& left, |
| 52 | const std::pair<Variable*, int>& right) { |
| 53 | return left.second < right.second; |
| 54 | } |
| 55 | }; |
| 56 | |
| 57 | Rewriter::~Rewriter() { |
| 58 | if (!temps_.empty()) { |
| 59 | // Ensure that we add temporaries in the order they appeared in old_scope_. |
| 60 | std::sort(temps_.begin(), temps_.end(), LessThanSecond()); |
| 61 | for (auto var_and_index : temps_) { |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 62 | var_and_index.first->set_scope(new_scope_closure_); |
| 63 | new_scope_closure_->AddTemporary(var_and_index.first); |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 64 | } |
| 65 | } |
| 66 | } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 67 | |
| 68 | void Rewriter::VisitFunctionLiteral(FunctionLiteral* function_literal) { |
| 69 | function_literal->scope()->ReplaceOuterScope(new_scope_); |
| 70 | } |
| 71 | |
| 72 | |
| 73 | void Rewriter::VisitClassLiteral(ClassLiteral* class_literal) { |
| 74 | class_literal->scope()->ReplaceOuterScope(new_scope_); |
| 75 | if (class_literal->extends() != nullptr) { |
| 76 | Visit(class_literal->extends()); |
| 77 | } |
| 78 | // No need to visit the constructor since it will have the class |
| 79 | // scope on its scope chain. |
| 80 | ZoneList<ObjectLiteralProperty*>* props = class_literal->properties(); |
| 81 | for (int i = 0; i < props->length(); ++i) { |
| 82 | ObjectLiteralProperty* prop = props->at(i); |
| 83 | if (!prop->key()->IsLiteral()) { |
| 84 | Visit(prop->key()); |
| 85 | } |
| 86 | // No need to visit the values, since all values are functions with |
| 87 | // the class scope on their scope chain. |
| 88 | DCHECK(prop->value()->IsFunctionLiteral()); |
| 89 | } |
| 90 | } |
| 91 | |
| 92 | |
| 93 | void Rewriter::VisitVariableProxy(VariableProxy* proxy) { |
| 94 | if (proxy->is_resolved()) { |
| 95 | Variable* var = proxy->var(); |
Ben Murdoch | da12d29 | 2016-06-02 14:46:10 +0100 | [diff] [blame] | 96 | if (var->mode() != TEMPORARY) return; |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 97 | // Temporaries are only placed in ClosureScopes. |
| 98 | DCHECK_EQ(var->scope(), var->scope()->ClosureScope()); |
| 99 | // If the temporary is already where it should be, return quickly. |
| 100 | if (var->scope() == new_scope_closure_) return; |
| 101 | int index = old_scope_closure_->RemoveTemporary(var); |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 102 | if (index >= 0) { |
| 103 | temps_.push_back(std::make_pair(var, index)); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 104 | } |
| 105 | } else if (old_scope_->RemoveUnresolved(proxy)) { |
| 106 | new_scope_->AddUnresolved(proxy); |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 111 | void Rewriter::VisitBlock(Block* stmt) { |
| 112 | if (stmt->scope() != nullptr) |
| 113 | stmt->scope()->ReplaceOuterScope(new_scope_); |
| 114 | else |
| 115 | VisitStatements(stmt->statements()); |
| 116 | } |
| 117 | |
| 118 | |
| 119 | void Rewriter::VisitTryCatchStatement(TryCatchStatement* stmt) { |
| 120 | Visit(stmt->try_block()); |
| 121 | stmt->scope()->ReplaceOuterScope(new_scope_); |
| 122 | } |
| 123 | |
| 124 | |
| 125 | void Rewriter::VisitWithStatement(WithStatement* stmt) { |
| 126 | Visit(stmt->expression()); |
| 127 | stmt->scope()->ReplaceOuterScope(new_scope_); |
| 128 | } |
| 129 | |
| 130 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 131 | } // anonymous namespace |
| 132 | |
| 133 | |
| 134 | void RewriteParameterInitializerScope(uintptr_t stack_limit, |
| 135 | Expression* initializer, Scope* old_scope, |
| 136 | Scope* new_scope) { |
| 137 | Rewriter rewriter(stack_limit, initializer, old_scope, new_scope); |
| 138 | rewriter.Run(); |
| 139 | } |
| 140 | |
| 141 | |
| 142 | } // namespace internal |
| 143 | } // namespace v8 |