| // statements.h -- Go frontend statements. -*- C++ -*- |
| |
| // Copyright 2009 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| #ifndef GO_STATEMENTS_H |
| #define GO_STATEMENTS_H |
| |
| #include "operator.h" |
| |
| class Gogo; |
| class Traverse; |
| class Statement_inserter; |
| class Block; |
| class Function; |
| class Unnamed_label; |
| class Export_function_body; |
| class Import_function_body; |
| class Assignment_statement; |
| class Temporary_statement; |
| class Variable_declaration_statement; |
| class Expression_statement; |
| class Block_statement; |
| class Return_statement; |
| class Thunk_statement; |
| class Defer_statement; |
| class Goto_statement; |
| class Goto_unnamed_statement; |
| class Label_statement; |
| class Unnamed_label_statement; |
| class If_statement; |
| class For_statement; |
| class For_range_statement; |
| class Switch_statement; |
| class Type_switch_statement; |
| class Send_statement; |
| class Select_statement; |
| class Variable; |
| class Named_object; |
| class Label; |
| class Translate_context; |
| class Expression; |
| class Expression_list; |
| class Struct_type; |
| class Call_expression; |
| class Map_index_expression; |
| class Receive_expression; |
| class Case_clauses; |
| class Type_case_clauses; |
| class Select_clauses; |
| class Typed_identifier_list; |
| class Bexpression; |
| class Bstatement; |
| class Bvariable; |
| class Ast_dump_context; |
| |
| // This class is used to traverse assignments made by a statement |
| // which makes assignments. |
| |
| class Traverse_assignments |
| { |
| public: |
| Traverse_assignments() |
| { } |
| |
| virtual ~Traverse_assignments() |
| { } |
| |
| // This is called for a variable initialization. |
| virtual void |
| initialize_variable(Named_object*) = 0; |
| |
| // This is called for each assignment made by the statement. PLHS |
| // points to the left hand side, and PRHS points to the right hand |
| // side. PRHS may be NULL if there is no associated expression, as |
| // in the bool set by a non-blocking receive. |
| virtual void |
| assignment(Expression** plhs, Expression** prhs) = 0; |
| |
| // This is called for each expression which is not passed to the |
| // assignment function. This is used for some of the statements |
| // which assign two values, for which there is no expression which |
| // describes the value. For ++ and -- the value is passed to both |
| // the assignment method and the rhs method. IS_STORED is true if |
| // this value is being stored directly. It is false if the value is |
| // computed but not stored. IS_LOCAL is true if the value is being |
| // stored in a local variable or this is being called by a return |
| // statement. |
| virtual void |
| value(Expression**, bool is_stored, bool is_local) = 0; |
| }; |
| |
| // A single statement. |
| |
| class Statement |
| { |
| public: |
| // The types of statements. |
| enum Statement_classification |
| { |
| STATEMENT_ERROR, |
| STATEMENT_VARIABLE_DECLARATION, |
| STATEMENT_TEMPORARY, |
| STATEMENT_ASSIGNMENT, |
| STATEMENT_EXPRESSION, |
| STATEMENT_BLOCK, |
| STATEMENT_GO, |
| STATEMENT_DEFER, |
| STATEMENT_RETURN, |
| STATEMENT_BREAK_OR_CONTINUE, |
| STATEMENT_GOTO, |
| STATEMENT_GOTO_UNNAMED, |
| STATEMENT_LABEL, |
| STATEMENT_UNNAMED_LABEL, |
| STATEMENT_IF, |
| STATEMENT_CONSTANT_SWITCH, |
| STATEMENT_SEND, |
| STATEMENT_SELECT, |
| |
| // These statements types are created by the parser, but they |
| // disappear during the lowering pass. |
| STATEMENT_ASSIGNMENT_OPERATION, |
| STATEMENT_TUPLE_ASSIGNMENT, |
| STATEMENT_TUPLE_MAP_ASSIGNMENT, |
| STATEMENT_TUPLE_RECEIVE_ASSIGNMENT, |
| STATEMENT_TUPLE_TYPE_GUARD_ASSIGNMENT, |
| STATEMENT_INCDEC, |
| STATEMENT_FOR, |
| STATEMENT_FOR_RANGE, |
| STATEMENT_SWITCH, |
| STATEMENT_TYPE_SWITCH |
| }; |
| |
| Statement(Statement_classification, Location); |
| |
| virtual ~Statement(); |
| |
| // Make a variable declaration. |
| static Statement* |
| make_variable_declaration(Named_object*); |
| |
| // Make a statement which creates a temporary variable and |
| // initializes it to an expression. The block is used if the |
| // temporary variable has to be explicitly destroyed; the variable |
| // must still be added to the block. References to the temporary |
| // variable may be constructed using make_temporary_reference. |
| // Either the type or the initialization expression may be NULL, but |
| // not both. |
| static Temporary_statement* |
| make_temporary(Type*, Expression*, Location); |
| |
| // Make an assignment statement. |
| static Assignment_statement* |
| make_assignment(Expression*, Expression*, Location); |
| |
| // Make an assignment operation (+=, etc.). |
| static Statement* |
| make_assignment_operation(Operator, Expression*, Expression*, |
| Location); |
| |
| // Make a tuple assignment statement. |
| static Statement* |
| make_tuple_assignment(Expression_list*, Expression_list*, Location); |
| |
| // Make an assignment from a map index to a pair of variables. |
| static Statement* |
| make_tuple_map_assignment(Expression* val, Expression* present, |
| Expression*, Location); |
| |
| // Make an assignment from a nonblocking receive to a pair of |
| // variables. |
| static Statement* |
| make_tuple_receive_assignment(Expression* val, Expression* closed, |
| Expression* channel, Location); |
| |
| // Make an assignment from a type guard to a pair of variables. |
| static Statement* |
| make_tuple_type_guard_assignment(Expression* val, Expression* ok, |
| Expression* expr, Type* type, |
| Location); |
| |
| // Make an expression statement from an Expression. IS_IGNORED is |
| // true if the value is being explicitly ignored, as in an |
| // assignment to _. |
| static Statement* |
| make_statement(Expression*, bool is_ignored); |
| |
| // Make a block statement from a Block. This is an embedded list of |
| // statements which may also include variable definitions. |
| static Block_statement* |
| make_block_statement(Block*, Location); |
| |
| // Make an increment statement. |
| static Statement* |
| make_inc_statement(Expression*); |
| |
| // Make a decrement statement. |
| static Statement* |
| make_dec_statement(Expression*); |
| |
| // Make a go statement. |
| static Statement* |
| make_go_statement(Call_expression* call, Location); |
| |
| // Make a defer statement. |
| static Statement* |
| make_defer_statement(Call_expression* call, Location); |
| |
| // Make a return statement. |
| static Return_statement* |
| make_return_statement(Expression_list*, Location); |
| |
| // Make a statement that returns the result of a call expression. |
| // If the call does not return any results, this just returns the |
| // call expression as a statement, assuming that the function will |
| // end immediately afterward. |
| static Statement* |
| make_return_from_call(Call_expression*, Location); |
| |
| // Make a break statement. |
| static Statement* |
| make_break_statement(Unnamed_label* label, Location); |
| |
| // Make a continue statement. |
| static Statement* |
| make_continue_statement(Unnamed_label* label, Location); |
| |
| // Make a goto statement. |
| static Statement* |
| make_goto_statement(Label* label, Location); |
| |
| // Make a goto statement to an unnamed label. |
| static Statement* |
| make_goto_unnamed_statement(Unnamed_label* label, Location); |
| |
| // Make a label statement--where the label is defined. |
| static Statement* |
| make_label_statement(Label* label, Location); |
| |
| // Make an unnamed label statement--where the label is defined. |
| static Statement* |
| make_unnamed_label_statement(Unnamed_label* label); |
| |
| // Make an if statement. |
| static Statement* |
| make_if_statement(Expression* cond, Block* then_block, Block* else_block, |
| Location); |
| |
| // Make a switch statement. |
| static Switch_statement* |
| make_switch_statement(Expression* switch_val, Location); |
| |
| // Make a type switch statement. |
| static Type_switch_statement* |
| make_type_switch_statement(const std::string&, Expression*, Location); |
| |
| // Make a send statement. |
| static Send_statement* |
| make_send_statement(Expression* channel, Expression* val, Location); |
| |
| // Make a select statement. |
| static Select_statement* |
| make_select_statement(Location); |
| |
| // Make a for statement. |
| static For_statement* |
| make_for_statement(Block* init, Expression* cond, Block* post, |
| Location location); |
| |
| // Make a for statement with a range clause. |
| static For_range_statement* |
| make_for_range_statement(Expression* index_var, Expression* value_var, |
| Expression* range, Location); |
| |
| // Return the statement classification. |
| Statement_classification |
| classification() const |
| { return this->classification_; } |
| |
| // Get the statement location. |
| Location |
| location() const |
| { return this->location_; } |
| |
| // Traverse the tree. |
| int |
| traverse(Block*, size_t* index, Traverse*); |
| |
| // Traverse the contents of this statement--the expressions and |
| // statements which it contains. |
| int |
| traverse_contents(Traverse*); |
| |
| // If this statement assigns some values, it calls a function for |
| // each value to which this statement assigns a value, and returns |
| // true. If this statement does not assign any values, it returns |
| // false. |
| bool |
| traverse_assignments(Traverse_assignments* tassign); |
| |
| // Lower a statement. This is called immediately after parsing to |
| // simplify statements for further processing. It returns the same |
| // Statement or a new one. FUNCTION is the function containing this |
| // statement. BLOCK is the block containing this statement. |
| // INSERTER can be used to insert new statements before this one. |
| Statement* |
| lower(Gogo* gogo, Named_object* function, Block* block, |
| Statement_inserter* inserter) |
| { return this->do_lower(gogo, function, block, inserter); } |
| |
| // Flatten a statement. This is called immediately after the order of |
| // evaluation rules are applied to statements. It returns the same |
| // Statement or a new one. FUNCTION is the function containing this |
| // statement. BLOCK is the block containing this statement. |
| // INSERTER can be used to insert new statements before this one. |
| Statement* |
| flatten(Gogo* gogo, Named_object* function, Block* block, |
| Statement_inserter* inserter) |
| { return this->do_flatten(gogo, function, block, inserter); } |
| |
| // Set type information for unnamed constants. |
| void |
| determine_types(); |
| |
| // Check types in a statement. This simply checks that any |
| // expressions used by the statement have the right type. |
| void |
| check_types(Gogo* gogo) |
| { this->do_check_types(gogo); } |
| |
| // Return the cost of this statement for inlining purposes. |
| int |
| inlining_cost() |
| { return this->do_inlining_cost(); } |
| |
| // Export data for this statement to BODY. |
| void |
| export_statement(Export_function_body* efb) |
| { this->do_export_statement(efb); } |
| |
| // Make implicit type conversions explicit. |
| void |
| add_conversions() |
| { this->do_add_conversions(); } |
| |
| // Read a statement from export data. The location should be used |
| // for the returned statement. Errors should be reported using the |
| // Import_function_body's location method. |
| static Statement* |
| import_statement(Import_function_body*, Location); |
| |
| // Return whether this is a block statement. |
| bool |
| is_block_statement() const |
| { return this->classification_ == STATEMENT_BLOCK; } |
| |
| // If this is an assignment statement, return it. Otherwise return |
| // NULL. |
| Assignment_statement* |
| assignment_statement() |
| { |
| return this->convert<Assignment_statement, STATEMENT_ASSIGNMENT>(); |
| } |
| |
| // If this is an temporary statement, return it. Otherwise return |
| // NULL. |
| Temporary_statement* |
| temporary_statement() |
| { |
| return this->convert<Temporary_statement, STATEMENT_TEMPORARY>(); |
| } |
| |
| // If this is a variable declaration statement, return it. |
| // Otherwise return NULL. |
| Variable_declaration_statement* |
| variable_declaration_statement() |
| { |
| return this->convert<Variable_declaration_statement, |
| STATEMENT_VARIABLE_DECLARATION>(); |
| } |
| |
| // If this is an expression statement, return it. Otherwise return |
| // NULL. |
| Expression_statement* |
| expression_statement() |
| { |
| return this->convert<Expression_statement, STATEMENT_EXPRESSION>(); |
| } |
| |
| // If this is an block statement, return it. Otherwise return |
| // NULL. |
| Block_statement* |
| block_statement() |
| { return this->convert<Block_statement, STATEMENT_BLOCK>(); } |
| |
| // If this is a return statement, return it. Otherwise return NULL. |
| Return_statement* |
| return_statement() |
| { return this->convert<Return_statement, STATEMENT_RETURN>(); } |
| |
| // If this is a thunk statement (a go or defer statement), return |
| // it. Otherwise return NULL. |
| Thunk_statement* |
| thunk_statement(); |
| |
| // If this is a defer statement, return it. Otherwise return NULL. |
| Defer_statement* |
| defer_statement() |
| { return this->convert<Defer_statement, STATEMENT_DEFER>(); } |
| |
| // If this is a goto statement, return it. Otherwise return NULL. |
| Goto_statement* |
| goto_statement() |
| { return this->convert<Goto_statement, STATEMENT_GOTO>(); } |
| |
| // If this is a goto_unnamed statement, return it. Otherwise return NULL. |
| Goto_unnamed_statement* |
| goto_unnamed_statement() |
| { return this->convert<Goto_unnamed_statement, STATEMENT_GOTO_UNNAMED>(); } |
| |
| // If this is a label statement, return it. Otherwise return NULL. |
| Label_statement* |
| label_statement() |
| { return this->convert<Label_statement, STATEMENT_LABEL>(); } |
| |
| // If this is an unnamed_label statement, return it. Otherwise return NULL. |
| Unnamed_label_statement* |
| unnamed_label_statement() |
| { return this->convert<Unnamed_label_statement, STATEMENT_UNNAMED_LABEL>(); } |
| |
| // If this is an if statement, return it. Otherwise return NULL. |
| If_statement* |
| if_statement() |
| { return this->convert<If_statement, STATEMENT_IF>(); } |
| |
| // If this is a for statement, return it. Otherwise return NULL. |
| For_statement* |
| for_statement() |
| { return this->convert<For_statement, STATEMENT_FOR>(); } |
| |
| // If this is a for statement over a range clause, return it. |
| // Otherwise return NULL. |
| For_range_statement* |
| for_range_statement() |
| { return this->convert<For_range_statement, STATEMENT_FOR_RANGE>(); } |
| |
| // If this is a switch statement, return it. Otherwise return NULL. |
| Switch_statement* |
| switch_statement() |
| { return this->convert<Switch_statement, STATEMENT_SWITCH>(); } |
| |
| // If this is a type switch statement, return it. Otherwise return |
| // NULL. |
| Type_switch_statement* |
| type_switch_statement() |
| { return this->convert<Type_switch_statement, STATEMENT_TYPE_SWITCH>(); } |
| |
| // If this is a send statement, return it. Otherwise return NULL. |
| Send_statement* |
| send_statement() |
| { return this->convert<Send_statement, STATEMENT_SEND>(); } |
| |
| // If this is a select statement, return it. Otherwise return NULL. |
| Select_statement* |
| select_statement() |
| { return this->convert<Select_statement, STATEMENT_SELECT>(); } |
| |
| // Return true if this statement may fall through--if after |
| // executing this statement we may go on to execute the following |
| // statement, if any. |
| bool |
| may_fall_through() const |
| { return this->do_may_fall_through(); } |
| |
| // Convert the statement to the backend representation. |
| Bstatement* |
| get_backend(Translate_context*); |
| |
| // Dump AST representation of a statement to a dump context. |
| void |
| dump_statement(Ast_dump_context*) const; |
| |
| protected: |
| // Implemented by child class: traverse the tree. |
| virtual int |
| do_traverse(Traverse*) = 0; |
| |
| // Implemented by child class: traverse assignments. Any statement |
| // which includes an assignment should implement this. |
| virtual bool |
| do_traverse_assignments(Traverse_assignments*) |
| { return false; } |
| |
| // Implemented by the child class: lower this statement to a simpler |
| // one. |
| virtual Statement* |
| do_lower(Gogo*, Named_object*, Block*, Statement_inserter*) |
| { return this; } |
| |
| // Implemented by the child class: lower this statement to a simpler |
| // one. |
| virtual Statement* |
| do_flatten(Gogo*, Named_object*, Block*, Statement_inserter*) |
| { return this; } |
| |
| // Implemented by child class: set type information for unnamed |
| // constants. Any statement which includes an expression needs to |
| // implement this. |
| virtual void |
| do_determine_types() |
| { } |
| |
| // Implemented by child class: check types of expressions used in a |
| // statement. |
| virtual void |
| do_check_types(Gogo*) |
| { } |
| |
| // Implemented by child class: return the cost of this statement for |
| // inlining. The default cost is high, so we only need to define |
| // this method for statements that can be inlined. |
| virtual int |
| do_inlining_cost() |
| { return 0x100000; } |
| |
| // Implemented by child class: write export data for this statement |
| // to the string. This need only be implemented by classes that |
| // implement do_inlining_cost with a reasonable value. |
| virtual void |
| do_export_statement(Export_function_body*) |
| { go_unreachable(); } |
| |
| // Implemented by child class: return true if this statement may |
| // fall through. |
| virtual bool |
| do_may_fall_through() const |
| { return true; } |
| |
| // Implemented by child class: convert to backend representation. |
| virtual Bstatement* |
| do_get_backend(Translate_context*) = 0; |
| |
| // Implemented by child class: dump ast representation. |
| virtual void |
| do_dump_statement(Ast_dump_context*) const = 0; |
| |
| // Implemented by child class: make implicit conversions explicit. |
| virtual void |
| do_add_conversions() |
| { } |
| |
| // Traverse an expression in a statement. |
| int |
| traverse_expression(Traverse*, Expression**); |
| |
| // Traverse an expression list in a statement. The Expression_list |
| // may be NULL. |
| int |
| traverse_expression_list(Traverse*, Expression_list*); |
| |
| // Traverse a type in a statement. |
| int |
| traverse_type(Traverse*, Type*); |
| |
| // For children to call when they detect that they are in error. |
| void |
| set_is_error(); |
| |
| // For children to call to report an error conveniently. |
| void |
| report_error(const char*); |
| |
| // For children to return an error statement from lower(). |
| static Statement* |
| make_error_statement(Location); |
| |
| private: |
| // Convert to the desired statement classification, or return NULL. |
| // This is a controlled dynamic cast. |
| template<typename Statement_class, Statement_classification sc> |
| Statement_class* |
| convert() |
| { |
| return (this->classification_ == sc |
| ? static_cast<Statement_class*>(this) |
| : NULL); |
| } |
| |
| template<typename Statement_class, Statement_classification sc> |
| const Statement_class* |
| convert() const |
| { |
| return (this->classification_ == sc |
| ? static_cast<const Statement_class*>(this) |
| : NULL); |
| } |
| |
| // The statement classification. |
| Statement_classification classification_; |
| // The location in the input file of the start of this statement. |
| Location location_; |
| }; |
| |
| // An assignment statement. |
| |
| class Assignment_statement : public Statement |
| { |
| public: |
| Assignment_statement(Expression* lhs, Expression* rhs, |
| Location location) |
| : Statement(STATEMENT_ASSIGNMENT, location), |
| lhs_(lhs), rhs_(rhs), omit_write_barrier_(false) |
| { } |
| |
| Expression* |
| lhs() const |
| { return this->lhs_; } |
| |
| Expression* |
| rhs() const |
| { return this->rhs_; } |
| |
| bool |
| omit_write_barrier() const |
| { return this->omit_write_barrier_; } |
| |
| void |
| set_omit_write_barrier() |
| { this->omit_write_barrier_ = true; } |
| |
| protected: |
| int |
| do_traverse(Traverse* traverse); |
| |
| bool |
| do_traverse_assignments(Traverse_assignments*); |
| |
| virtual Statement* |
| do_lower(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| void |
| do_determine_types(); |
| |
| void |
| do_check_types(Gogo*); |
| |
| int |
| do_inlining_cost() |
| { return 1; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| Statement* |
| do_flatten(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| void |
| do_add_conversions(); |
| |
| private: |
| // Left hand side--the lvalue. |
| Expression* lhs_; |
| // Right hand side--the rvalue. |
| Expression* rhs_; |
| // True if we can omit a write barrier from this assignment. |
| bool omit_write_barrier_; |
| }; |
| |
| // A statement which creates and initializes a temporary variable. |
| |
| class Temporary_statement : public Statement |
| { |
| public: |
| Temporary_statement(Type* type, Expression* init, Location location) |
| : Statement(STATEMENT_TEMPORARY, location), |
| type_(type), init_(init), bvariable_(NULL), is_address_taken_(false), |
| value_escapes_(false), assigned_(false), uses_(0) |
| { } |
| |
| // Return the type of the temporary variable. |
| Type* |
| type() const; |
| |
| // Return the initializer if there is one. |
| Expression* |
| init() const |
| { return this->init_; } |
| |
| // Set the initializer. |
| void |
| set_init(Expression* expr) |
| { this->init_ = expr; } |
| |
| // Whether something takes the address of this temporary |
| // variable. |
| bool |
| is_address_taken() |
| { return this->is_address_taken_; } |
| |
| // Record that something takes the address of this temporary |
| // variable. |
| void |
| set_is_address_taken() |
| { this->is_address_taken_ = true; } |
| |
| // Whether the value escapes. |
| bool |
| value_escapes() const |
| { return this->value_escapes_; } |
| |
| // Record that the value escapes. |
| void |
| set_value_escapes() |
| { this->value_escapes_ = true; } |
| |
| // Whether this temporary variable is assigned (after initialization). |
| bool |
| assigned() |
| { return this->assigned_; } |
| |
| // Record that this temporary variable is assigned. |
| void |
| set_assigned() |
| { this->assigned_ = true; } |
| |
| // Number of uses of this temporary variable. |
| int |
| uses() |
| { return this->uses_; } |
| |
| // Add one use of this temporary variable. |
| void |
| add_use() |
| { this->uses_++; } |
| |
| // Return the temporary variable. This should not be called until |
| // after the statement itself has been converted. |
| Bvariable* |
| get_backend_variable(Translate_context*) const; |
| |
| // Import the declaration of a temporary. |
| static Statement* |
| do_import(Import_function_body*, Location); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| bool |
| do_traverse_assignments(Traverse_assignments*); |
| |
| void |
| do_determine_types(); |
| |
| void |
| do_check_types(Gogo*); |
| |
| int |
| do_inlining_cost() |
| { return 1; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| Statement* |
| do_flatten(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| void |
| do_add_conversions(); |
| |
| private: |
| // The type of the temporary variable. |
| Type* type_; |
| // The initial value of the temporary variable. This may be NULL. |
| Expression* init_; |
| // The backend representation of the temporary variable. |
| Bvariable* bvariable_; |
| // True if something takes the address of this temporary variable. |
| bool is_address_taken_; |
| // True if the value assigned to this temporary variable escapes. |
| // This is used for select statements. |
| bool value_escapes_; |
| // True if this temporary variable is assigned (after initialization). |
| bool assigned_; |
| // Number of uses of this temporary variable. |
| int uses_; |
| }; |
| |
| // A variable declaration. This marks the point in the code where a |
| // variable is declared. The Variable is also attached to a Block. |
| |
| class Variable_declaration_statement : public Statement |
| { |
| public: |
| Variable_declaration_statement(Named_object* var); |
| |
| // The variable being declared. |
| Named_object* |
| var() |
| { return this->var_; } |
| |
| // Import a variable declaration. |
| static Statement* |
| do_import(Import_function_body*, Location); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| bool |
| do_traverse_assignments(Traverse_assignments*); |
| |
| Statement* |
| do_lower(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| int |
| do_inlining_cost() |
| { return 1; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| Statement* |
| do_flatten(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| void |
| do_add_conversions(); |
| |
| private: |
| Named_object* var_; |
| }; |
| |
| // A return statement. |
| |
| class Return_statement : public Statement |
| { |
| public: |
| Return_statement(Expression_list* vals, Location location) |
| : Statement(STATEMENT_RETURN, location), |
| vals_(vals), is_lowered_(false) |
| { } |
| |
| // The list of values being returned. This may be NULL. |
| const Expression_list* |
| vals() const |
| { return this->vals_; } |
| |
| protected: |
| int |
| do_traverse(Traverse* traverse) |
| { return this->traverse_expression_list(traverse, this->vals_); } |
| |
| bool |
| do_traverse_assignments(Traverse_assignments*); |
| |
| Statement* |
| do_lower(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| bool |
| do_may_fall_through() const |
| { return false; } |
| |
| int |
| do_inlining_cost() |
| { return 1; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| // Return values. This may be NULL. |
| Expression_list* vals_; |
| // True if this statement has been lowered. |
| bool is_lowered_; |
| }; |
| |
| // An expression statement. |
| |
| class Expression_statement : public Statement |
| { |
| public: |
| Expression_statement(Expression* expr, bool is_ignored); |
| |
| Expression* |
| expr() |
| { return this->expr_; } |
| |
| protected: |
| int |
| do_traverse(Traverse* traverse) |
| { return this->traverse_expression(traverse, &this->expr_); } |
| |
| void |
| do_determine_types(); |
| |
| void |
| do_check_types(Gogo*); |
| |
| bool |
| do_may_fall_through() const; |
| |
| int |
| do_inlining_cost() |
| { return 0; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| Bstatement* |
| do_get_backend(Translate_context* context); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| Expression* expr_; |
| // Whether the value of this expression is being explicitly ignored. |
| bool is_ignored_; |
| }; |
| |
| // A block statement--a list of statements which may include variable |
| // definitions. |
| |
| class Block_statement : public Statement |
| { |
| public: |
| Block_statement(Block* block, Location location) |
| : Statement(STATEMENT_BLOCK, location), |
| block_(block), is_lowered_for_statement_(false) |
| { } |
| |
| // Return the actual block. |
| Block* |
| block() const |
| { return this->block_; } |
| |
| void |
| set_is_lowered_for_statement() |
| { this->is_lowered_for_statement_ = true; } |
| |
| bool |
| is_lowered_for_statement() |
| { return this->is_lowered_for_statement_; } |
| |
| // Export a block for a block statement. |
| static void |
| export_block(Export_function_body*, Block*, bool is_lowered_for_statement); |
| |
| // Import a block statement, returning the block. |
| // *IS_LOWERED_FOR_STATEMENT reports whether this block statement |
| // was lowered from a for statement. |
| static Block* |
| do_import(Import_function_body*, Location, bool* is_lowered_for_statement); |
| |
| protected: |
| int |
| do_traverse(Traverse* traverse) |
| { return this->block_->traverse(traverse); } |
| |
| void |
| do_determine_types() |
| { this->block_->determine_types(); } |
| |
| int |
| do_inlining_cost() |
| { return 0; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| bool |
| do_may_fall_through() const |
| { return this->block_->may_fall_through(); } |
| |
| Bstatement* |
| do_get_backend(Translate_context* context); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| Block* block_; |
| // True if this block statement represents a lowered for statement. |
| bool is_lowered_for_statement_; |
| }; |
| |
| // A send statement. |
| |
| class Send_statement : public Statement |
| { |
| public: |
| Send_statement(Expression* channel, Expression* val, |
| Location location) |
| : Statement(STATEMENT_SEND, location), |
| channel_(channel), val_(val) |
| { } |
| |
| Expression* |
| channel() |
| { return this->channel_; } |
| |
| Expression* |
| val() |
| { return this->val_; } |
| |
| protected: |
| int |
| do_traverse(Traverse* traverse); |
| |
| void |
| do_determine_types(); |
| |
| void |
| do_check_types(Gogo*); |
| |
| Statement* |
| do_flatten(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| void |
| do_add_conversions(); |
| |
| private: |
| // The channel on which to send the value. |
| Expression* channel_; |
| // The value to send. |
| Expression* val_; |
| }; |
| |
| // Select_clauses holds the clauses of a select statement. This is |
| // built by the parser. |
| |
| class Select_clauses |
| { |
| public: |
| Select_clauses() |
| : clauses_() |
| { } |
| |
| // Add a new clause. IS_SEND is true if this is a send clause, |
| // false for a receive clause. For a send clause CHANNEL is the |
| // channel and VAL is the value to send. For a receive clause |
| // CHANNEL is the channel, VAL is either NULL or a Var_expression |
| // for the variable to set, and CLOSED is either NULL or a |
| // Var_expression to set to whether the channel is closed. If VAL |
| // is NULL, VAR may be a variable to be initialized with the |
| // received value, and CLOSEDVAR may be a variable to be initialized |
| // with whether the channel is closed. IS_DEFAULT is true if this |
| // is the default clause. STATEMENTS is the list of statements to |
| // execute. |
| void |
| add(bool is_send, Expression* channel, Expression* val, Expression* closed, |
| Named_object* var, Named_object* closedvar, bool is_default, |
| Block* statements, Location location) |
| { |
| this->clauses_.push_back(Select_clause(is_send, channel, val, closed, var, |
| closedvar, is_default, statements, |
| location)); |
| } |
| |
| size_t |
| size() const |
| { return this->clauses_.size(); } |
| |
| // Traverse the select clauses. |
| int |
| traverse(Traverse*); |
| |
| // Lower statements. |
| void |
| lower(Gogo*, Named_object*, Block*, Temporary_statement*, |
| Temporary_statement*); |
| |
| // Determine types. |
| void |
| determine_types(); |
| |
| // Check types. |
| void |
| check_types(); |
| |
| // Whether the select clauses may fall through to the statement |
| // which follows the overall select statement. |
| bool |
| may_fall_through() const; |
| |
| // Convert to the backend representation. |
| Bstatement* |
| get_backend(Translate_context*, Temporary_statement* index, |
| Unnamed_label* break_label, Location); |
| |
| // Dump AST representation. |
| void |
| dump_clauses(Ast_dump_context*) const; |
| |
| // A single clause. |
| class Select_clause |
| { |
| public: |
| Select_clause() |
| : channel_(NULL), val_(NULL), closed_(NULL), var_(NULL), |
| closedvar_(NULL), statements_(NULL), is_send_(false), |
| is_default_(false) |
| { } |
| |
| Select_clause(bool is_send, Expression* channel, Expression* val, |
| Expression* closed, Named_object* var, |
| Named_object* closedvar, bool is_default, Block* statements, |
| Location location) |
| : channel_(channel), val_(val), closed_(closed), var_(var), |
| closedvar_(closedvar), statements_(statements), location_(location), |
| is_send_(is_send), is_default_(is_default), is_lowered_(false) |
| { go_assert(is_default ? channel == NULL : channel != NULL); } |
| |
| // Traverse the select clause. |
| int |
| traverse(Traverse*); |
| |
| // Lower statements. |
| void |
| lower(Gogo*, Named_object*, Block*, Temporary_statement*, size_t, |
| Temporary_statement*); |
| |
| // Determine types. |
| void |
| determine_types(); |
| |
| // Check types. |
| void |
| check_types(); |
| |
| // Return true if this is the default clause. |
| bool |
| is_default() const |
| { return this->is_default_; } |
| |
| // Return the channel. This will return NULL for the default |
| // clause. |
| Expression* |
| channel() const |
| { return this->channel_; } |
| |
| // Return true for a send, false for a receive. |
| bool |
| is_send() const |
| { |
| go_assert(!this->is_default_); |
| return this->is_send_; |
| } |
| |
| // Return the value to send or the lvalue to receive into. |
| Expression* |
| val() const |
| { return this->val_; } |
| |
| // Return the lvalue to set to whether the channel is closed |
| // on a receive. |
| Expression* |
| closed() const |
| { return this->closed_; } |
| |
| // Return the variable to initialize, for "case a := <-ch". |
| Named_object* |
| var() const |
| { return this->var_; } |
| |
| // Return the variable to initialize to whether the channel |
| // is closed, for "case a, c := <-ch". |
| Named_object* |
| closedvar() const |
| { return this->closedvar_; } |
| |
| // Return the statements. |
| Block* |
| statements() const |
| { return this->statements_; } |
| |
| // Return the location. |
| Location |
| location() const |
| { return this->location_; } |
| |
| // Whether this clause may fall through to the statement which |
| // follows the overall select statement. |
| bool |
| may_fall_through() const; |
| |
| // Convert the statements to the backend representation. |
| Bstatement* |
| get_statements_backend(Translate_context*); |
| |
| // Dump AST representation. |
| void |
| dump_clause(Ast_dump_context*) const; |
| |
| private: |
| // These values must match the values in libgo/go/runtime/select.go. |
| enum |
| { |
| caseRecv = 1, |
| caseSend = 2, |
| caseDefault = 3, |
| }; |
| |
| void |
| lower_default(Block*, Expression*); |
| |
| void |
| lower_send(Block*, Expression*, Expression*); |
| |
| void |
| lower_recv(Gogo*, Named_object*, Block*, Expression*, Expression*, |
| Temporary_statement*); |
| |
| void |
| set_case(Block*, Expression*, Expression*, Expression*, int); |
| |
| // The channel. |
| Expression* channel_; |
| // The value to send or the lvalue to receive into. |
| Expression* val_; |
| // The lvalue to set to whether the channel is closed on a |
| // receive. |
| Expression* closed_; |
| // The variable to initialize, for "case a := <-ch". |
| Named_object* var_; |
| // The variable to initialize to whether the channel is closed, |
| // for "case a, c := <-ch". |
| Named_object* closedvar_; |
| // The statements to execute. |
| Block* statements_; |
| // The location of this clause. |
| Location location_; |
| // Whether this is a send or a receive. |
| bool is_send_; |
| // Whether this is the default. |
| bool is_default_; |
| // Whether this has been lowered. |
| bool is_lowered_; |
| }; |
| |
| Select_clause& |
| at(size_t i) |
| { return this->clauses_.at(i); } |
| |
| private: |
| typedef std::vector<Select_clause> Clauses; |
| |
| Clauses clauses_; |
| }; |
| |
| // A select statement. |
| |
| class Select_statement : public Statement |
| { |
| public: |
| Select_statement(Location location) |
| : Statement(STATEMENT_SELECT, location), |
| clauses_(NULL), index_(NULL), break_label_(NULL), is_lowered_(false) |
| { } |
| |
| // Add the clauses. |
| void |
| add_clauses(Select_clauses* clauses) |
| { |
| go_assert(this->clauses_ == NULL); |
| this->clauses_ = clauses; |
| } |
| |
| // Return the break label for this select statement. |
| Unnamed_label* |
| break_label(); |
| |
| protected: |
| int |
| do_traverse(Traverse* traverse) |
| { return this->clauses_->traverse(traverse); } |
| |
| Statement* |
| do_lower(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| void |
| do_determine_types() |
| { this->clauses_->determine_types(); } |
| |
| void |
| do_check_types(Gogo*) |
| { this->clauses_->check_types(); } |
| |
| bool |
| do_may_fall_through() const; |
| |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| // Lower a one-case select statement. |
| Statement* |
| lower_one_case(Block*); |
| |
| // Lower a two-case select statement with one defualt case. |
| Statement* |
| lower_two_case(Block*); |
| |
| // The select clauses. |
| Select_clauses* clauses_; |
| // A temporary that holds the index value returned by selectgo. |
| Temporary_statement* index_; |
| // The break label. |
| Unnamed_label* break_label_; |
| // Whether this statement has been lowered. |
| bool is_lowered_; |
| }; |
| |
| // A statement which requires a thunk: go or defer. |
| |
| class Thunk_statement : public Statement |
| { |
| public: |
| Thunk_statement(Statement_classification, Call_expression*, |
| Location); |
| |
| // Return the call expression. |
| Expression* |
| call() const |
| { return this->call_; } |
| |
| // Simplify a go or defer statement so that it only uses a single |
| // parameter. |
| bool |
| simplify_statement(Gogo*, Named_object*, Block*); |
| |
| protected: |
| int |
| do_traverse(Traverse* traverse); |
| |
| bool |
| do_traverse_assignments(Traverse_assignments*); |
| |
| void |
| do_determine_types(); |
| |
| void |
| do_check_types(Gogo*); |
| |
| // Return the function and argument for the call. |
| bool |
| get_fn_and_arg(Expression** pfn, Expression** parg); |
| |
| private: |
| // Return whether this is a simple go statement. |
| bool |
| is_simple(Function_type*) const; |
| |
| // Return whether the thunk function is a constant. |
| bool |
| is_constant_function() const; |
| |
| // Build the struct to use for a complex case. |
| Struct_type* |
| build_struct(Function_type* fntype); |
| |
| // Build the thunk. |
| void |
| build_thunk(Gogo*, const std::string&); |
| |
| // Set the name to use for thunk field N. |
| void |
| thunk_field_param(int n, char* buf, size_t buflen); |
| |
| // The function call to be executed in a separate thread (go) or |
| // later (defer). |
| Expression* call_; |
| // The type used for a struct to pass to a thunk, if this is not a |
| // simple call. |
| Struct_type* struct_type_; |
| }; |
| |
| // A go statement. |
| |
| class Go_statement : public Thunk_statement |
| { |
| public: |
| Go_statement(Call_expression* call, Location location) |
| : Thunk_statement(STATEMENT_GO, call, location) |
| { } |
| |
| protected: |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| }; |
| |
| // A defer statement. |
| |
| class Defer_statement : public Thunk_statement |
| { |
| public: |
| Defer_statement(Call_expression* call, Location location) |
| : Thunk_statement(STATEMENT_DEFER, call, location), |
| on_stack_(false) |
| { } |
| |
| void |
| set_on_stack() |
| { this->on_stack_ = true; } |
| |
| protected: |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| static Type* |
| defer_struct_type(); |
| |
| bool on_stack_; |
| }; |
| |
| // A goto statement. |
| |
| class Goto_statement : public Statement |
| { |
| public: |
| Goto_statement(Label* label, Location location) |
| : Statement(STATEMENT_GOTO, location), |
| label_(label) |
| { } |
| |
| // Return the label being jumped to. |
| Label* |
| label() const |
| { return this->label_; } |
| |
| // Import a goto statement. |
| static Statement* |
| do_import(Import_function_body*, Location); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| void |
| do_check_types(Gogo*); |
| |
| bool |
| do_may_fall_through() const |
| { return false; } |
| |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| int |
| do_inlining_cost() |
| { return 5; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| Label* label_; |
| }; |
| |
| // A goto statement to an unnamed label. |
| |
| class Goto_unnamed_statement : public Statement |
| { |
| public: |
| Goto_unnamed_statement(Unnamed_label* label, Location location) |
| : Statement(STATEMENT_GOTO_UNNAMED, location), |
| label_(label) |
| { } |
| |
| Unnamed_label* |
| unnamed_label() const |
| { return this->label_; } |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| bool |
| do_may_fall_through() const |
| { return false; } |
| |
| Bstatement* |
| do_get_backend(Translate_context* context); |
| |
| int |
| do_inlining_cost() |
| { return 5; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| Unnamed_label* label_; |
| }; |
| |
| // A label statement. |
| |
| class Label_statement : public Statement |
| { |
| public: |
| Label_statement(Label* label, Location location) |
| : Statement(STATEMENT_LABEL, location), |
| label_(label) |
| { } |
| |
| // Return the label itself. |
| Label* |
| label() const |
| { return this->label_; } |
| |
| // Import a label or unnamed label. |
| static Statement* |
| do_import(Import_function_body*, Location); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| int |
| do_inlining_cost() |
| { return 1; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| // The label. |
| Label* label_; |
| }; |
| |
| // An unnamed label statement. |
| |
| class Unnamed_label_statement : public Statement |
| { |
| public: |
| Unnamed_label_statement(Unnamed_label* label); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| Bstatement* |
| do_get_backend(Translate_context* context); |
| |
| int |
| do_inlining_cost() |
| { return 1; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| // The label. |
| Unnamed_label* label_; |
| }; |
| |
| // An if statement. |
| |
| class If_statement : public Statement |
| { |
| public: |
| If_statement(Expression* cond, Block* then_block, Block* else_block, |
| Location location) |
| : Statement(STATEMENT_IF, location), |
| cond_(cond), then_block_(then_block), else_block_(else_block) |
| { } |
| |
| Expression* |
| condition() const |
| { return this->cond_; } |
| |
| Block* |
| then_block() const |
| { return this->then_block_; } |
| |
| Block* |
| else_block() const |
| { return this->else_block_; } |
| |
| // Import an if statement. |
| static Statement* |
| do_import(Import_function_body*, Location); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| void |
| do_determine_types(); |
| |
| void |
| do_check_types(Gogo*); |
| |
| int |
| do_inlining_cost() |
| { return 5; } |
| |
| void |
| do_export_statement(Export_function_body*); |
| |
| bool |
| do_may_fall_through() const; |
| |
| Bstatement* |
| do_get_backend(Translate_context*); |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| Expression* cond_; |
| Block* then_block_; |
| Block* else_block_; |
| }; |
| |
| // A for statement. |
| |
| class For_statement : public Statement |
| { |
| public: |
| For_statement(Block* init, Expression* cond, Block* post, |
| Location location) |
| : Statement(STATEMENT_FOR, location), |
| init_(init), cond_(cond), post_(post), statements_(NULL), |
| break_label_(NULL), continue_label_(NULL) |
| { } |
| |
| // Add the statements. |
| void |
| add_statements(Block* statements) |
| { |
| go_assert(this->statements_ == NULL); |
| this->statements_ = statements; |
| } |
| |
| // Return the break label for this for statement. |
| Unnamed_label* |
| break_label(); |
| |
| // Return the continue label for this for statement. |
| Unnamed_label* |
| continue_label(); |
| |
| // Set the break and continue labels for this statement. |
| void |
| set_break_continue_labels(Unnamed_label* break_label, |
| Unnamed_label* continue_label); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| bool |
| do_traverse_assignments(Traverse_assignments*) |
| { go_unreachable(); } |
| |
| Statement* |
| do_lower(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| bool |
| do_may_fall_through() const; |
| |
| Bstatement* |
| do_get_backend(Translate_context*) |
| { go_unreachable(); } |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| // The initialization statements. This may be NULL. |
| Block* init_; |
| // The condition. This may be NULL. |
| Expression* cond_; |
| // The statements to run after each iteration. This may be NULL. |
| Block* post_; |
| // The statements in the loop itself. |
| Block* statements_; |
| // The break label, if needed. |
| Unnamed_label* break_label_; |
| // The continue label, if needed. |
| Unnamed_label* continue_label_; |
| }; |
| |
| // A for statement over a range clause. |
| |
| class For_range_statement : public Statement |
| { |
| public: |
| For_range_statement(Expression* index_var, Expression* value_var, |
| Expression* range, Location location) |
| : Statement(STATEMENT_FOR_RANGE, location), |
| index_var_(index_var), value_var_(value_var), range_(range), |
| statements_(NULL), break_label_(NULL), continue_label_(NULL) |
| { } |
| |
| // Add the statements. |
| void |
| add_statements(Block* statements) |
| { |
| go_assert(this->statements_ == NULL); |
| this->statements_ = statements; |
| } |
| |
| // Return the break label for this for statement. |
| Unnamed_label* |
| break_label(); |
| |
| // Return the continue label for this for statement. |
| Unnamed_label* |
| continue_label(); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| bool |
| do_traverse_assignments(Traverse_assignments*) |
| { go_unreachable(); } |
| |
| Statement* |
| do_lower(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| Bstatement* |
| do_get_backend(Translate_context*) |
| { go_unreachable(); } |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| private: |
| Expression* |
| make_range_ref(Named_object*, Temporary_statement*, Location); |
| |
| Call_expression* |
| call_builtin(Gogo*, const char* funcname, Expression* arg, Location); |
| |
| void |
| lower_range_array(Gogo*, Block*, Block*, Named_object*, Temporary_statement*, |
| Temporary_statement*, Temporary_statement*, |
| Block**, Expression**, Block**, Block**); |
| |
| void |
| lower_range_slice(Gogo*, Block*, Block*, Named_object*, Temporary_statement*, |
| Temporary_statement*, Temporary_statement*, |
| Block**, Expression**, Block**, Block**); |
| |
| void |
| lower_range_string(Gogo*, Block*, Block*, Named_object*, Temporary_statement*, |
| Temporary_statement*, Temporary_statement*, |
| Block**, Expression**, Block**, Block**); |
| |
| void |
| lower_range_map(Gogo*, Map_type*, Block*, Block*, Named_object*, |
| Temporary_statement*, Temporary_statement*, |
| Temporary_statement*, Block**, Expression**, Block**, |
| Block**); |
| |
| void |
| lower_range_channel(Gogo*, Block*, Block*, Named_object*, |
| Temporary_statement*, Temporary_statement*, |
| Temporary_statement*, Block**, Expression**, Block**, |
| Block**); |
| |
| Statement* |
| lower_map_range_clear(Type*, Block*, Expression*, Named_object*, |
| Temporary_statement*, Location); |
| |
| Statement* |
| lower_array_range_clear(Gogo*, Type*, Expression*, Block*, |
| Named_object*, Temporary_statement*, |
| Location); |
| |
| // The variable which is set to the index value. |
| Expression* index_var_; |
| // The variable which is set to the element value. This may be |
| // NULL. |
| Expression* value_var_; |
| // The expression we are ranging over. |
| Expression* range_; |
| // The statements in the block. |
| Block* statements_; |
| // The break label, if needed. |
| Unnamed_label* break_label_; |
| // The continue label, if needed. |
| Unnamed_label* continue_label_; |
| }; |
| |
| // Class Case_clauses holds the clauses of a switch statement. This |
| // is built by the parser. |
| |
| class Case_clauses |
| { |
| public: |
| Case_clauses() |
| : clauses_() |
| { } |
| |
| // Add a new clause. CASES is a list of case expressions; it may be |
| // NULL. IS_DEFAULT is true if this is the default case. |
| // STATEMENTS is a block of statements. IS_FALLTHROUGH is true if |
| // after the statements the case clause should fall through to the |
| // next clause. |
| void |
| add(Expression_list* cases, bool is_default, Block* statements, |
| bool is_fallthrough, Location location) |
| { |
| this->clauses_.push_back(Case_clause(cases, is_default, statements, |
| is_fallthrough, location)); |
| } |
| |
| // Return whether there are no clauses. |
| bool |
| empty() const |
| { return this->clauses_.empty(); } |
| |
| // Traverse the case clauses. |
| int |
| traverse(Traverse*); |
| |
| // Lower for a nonconstant switch. |
| void |
| lower(Block*, Temporary_statement*, Unnamed_label*) const; |
| |
| // Determine types of expressions. The Type parameter is the type |
| // of the switch value. |
| void |
| determine_types(Type*); |
| |
| // Check types. The Type parameter is the type of the switch value. |
| bool |
| check_types(Type*); |
| |
| // Return true if all the clauses are constant values. |
| bool |
| is_constant() const; |
| |
| // Return true if these clauses may fall through to the statements |
| // following the switch statement. |
| bool |
| may_fall_through() const; |
| |
| // Return the body of a SWITCH_EXPR when all the clauses are |
| // constants. |
| void |
| get_backend(Translate_context*, Unnamed_label* break_label, |
| std::vector<std::vector<Bexpression*> >* all_cases, |
| std::vector<Bstatement*>* all_statements) const; |
| |
| // Dump the AST representation to a dump context. |
| void |
| dump_clauses(Ast_dump_context*) const; |
| |
| private: |
| // For a constant switch we need to keep a record of constants we |
| // have already seen. |
| class Hash_integer_value; |
| class Eq_integer_value; |
| typedef Unordered_set_hash(Expression*, Hash_integer_value, |
| Eq_integer_value) Case_constants; |
| |
| // One case clause. |
| class Case_clause |
| { |
| public: |
| Case_clause() |
| : cases_(NULL), statements_(NULL), is_default_(false), |
| is_fallthrough_(false), location_(Linemap::unknown_location()) |
| { } |
| |
| Case_clause(Expression_list* cases, bool is_default, Block* statements, |
| bool is_fallthrough, Location location) |
| : cases_(cases), statements_(statements), is_default_(is_default), |
| is_fallthrough_(is_fallthrough), location_(location) |
| { } |
| |
| // Whether this clause falls through to the next clause. |
| bool |
| is_fallthrough() const |
| { return this->is_fallthrough_; } |
| |
| // Whether this is the default. |
| bool |
| is_default() const |
| { return this->is_default_; } |
| |
| // The location of this clause. |
| Location |
| location() const |
| { return this->location_; } |
| |
| // Traversal. |
| int |
| traverse(Traverse*); |
| |
| // Lower for a nonconstant switch. |
| void |
| lower(Block*, Temporary_statement*, Unnamed_label*, Unnamed_label*) const; |
| |
| // Determine types. |
| void |
| determine_types(Type*); |
| |
| // Check types. |
| bool |
| check_types(Type*); |
| |
| // Return true if all the case expressions are constant. |
| bool |
| is_constant() const; |
| |
| // Return true if this clause may fall through to execute the |
| // statements following the switch statement. This is not the |
| // same as whether this clause falls through to the next clause. |
| bool |
| may_fall_through() const; |
| |
| // Convert the case values and statements to the backend |
| // representation. |
| Bstatement* |
| get_backend(Translate_context*, Unnamed_label* break_label, |
| Case_constants*, std::vector<Bexpression*>* cases) const; |
| |
| // Dump the AST representation to a dump context. |
| void |
| dump_clause(Ast_dump_context*) const; |
| |
| private: |
| // The list of case expressions. |
| Expression_list* cases_; |
| // The statements to execute. |
| Block* statements_; |
| // Whether this is the default case. |
| bool is_default_; |
| // Whether this falls through after the statements. |
| bool is_fallthrough_; |
| // The location of this case clause. |
| Location location_; |
| }; |
| |
| friend class Case_clause; |
| |
| // The type of the list of clauses. |
| typedef std::vector<Case_clause> Clauses; |
| |
| // All the case clauses. |
| Clauses clauses_; |
| }; |
| |
| // A switch statement. |
| |
| class Switch_statement : public Statement |
| { |
| public: |
| Switch_statement(Expression* val, Location location) |
| : Statement(STATEMENT_SWITCH, location), |
| val_(val), clauses_(NULL), break_label_(NULL) |
| { } |
| |
| // Add the clauses. |
| void |
| add_clauses(Case_clauses* clauses) |
| { |
| go_assert(this->clauses_ == NULL); |
| this->clauses_ = clauses; |
| } |
| |
| // Return the break label for this switch statement. |
| Unnamed_label* |
| break_label(); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| Statement* |
| do_lower(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| Bstatement* |
| do_get_backend(Translate_context*) |
| { go_unreachable(); } |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| bool |
| do_may_fall_through() const; |
| |
| private: |
| // The value to switch on. This may be NULL. |
| Expression* val_; |
| // The case clauses. |
| Case_clauses* clauses_; |
| // The break label, if needed. |
| Unnamed_label* break_label_; |
| }; |
| |
| // Class Type_case_clauses holds the clauses of a type switch |
| // statement. This is built by the parser. |
| |
| class Type_case_clauses |
| { |
| public: |
| Type_case_clauses() |
| : clauses_() |
| { } |
| |
| // Add a new clause. TYPE is the type for this clause; it may be |
| // NULL. IS_FALLTHROUGH is true if this falls through to the next |
| // clause; in this case STATEMENTS will be NULL. IS_DEFAULT is true |
| // if this is the default case. STATEMENTS is a block of |
| // statements; it may be NULL. |
| void |
| add(Type* type, bool is_fallthrough, bool is_default, Block* statements, |
| Location location) |
| { |
| this->clauses_.push_back(Type_case_clause(type, is_fallthrough, is_default, |
| statements, location)); |
| } |
| |
| // Return whether there are no clauses. |
| bool |
| empty() const |
| { return this->clauses_.empty(); } |
| |
| // Traverse the type case clauses. |
| int |
| traverse(Traverse*); |
| |
| // Check for duplicates. |
| void |
| check_duplicates() const; |
| |
| // Lower to if and goto statements. |
| void |
| lower(Type*, Block*, Temporary_statement* descriptor_temp, |
| Unnamed_label* break_label) const; |
| |
| // Return true if these clauses may fall through to the statements |
| // following the switch statement. |
| bool |
| may_fall_through() const; |
| |
| // Dump the AST representation to a dump context. |
| void |
| dump_clauses(Ast_dump_context*) const; |
| |
| private: |
| // One type case clause. |
| class Type_case_clause |
| { |
| public: |
| Type_case_clause() |
| : type_(NULL), statements_(NULL), is_default_(false), |
| location_(Linemap::unknown_location()) |
| { } |
| |
| Type_case_clause(Type* type, bool is_fallthrough, bool is_default, |
| Block* statements, Location location) |
| : type_(type), statements_(statements), is_fallthrough_(is_fallthrough), |
| is_default_(is_default), location_(location) |
| { } |
| |
| // The type. |
| Type* |
| type() const |
| { return this->type_; } |
| |
| // Whether this is the default. |
| bool |
| is_default() const |
| { return this->is_default_; } |
| |
| // The location of this type clause. |
| Location |
| location() const |
| { return this->location_; } |
| |
| // Traversal. |
| int |
| traverse(Traverse*); |
| |
| // Lower to if and goto statements. |
| void |
| lower(Type*, Block*, Temporary_statement* descriptor_temp, |
| Unnamed_label* break_label, Unnamed_label** stmts_label) const; |
| |
| // Return true if this clause may fall through to execute the |
| // statements following the switch statement. This is not the |
| // same as whether this clause falls through to the next clause. |
| bool |
| may_fall_through() const; |
| |
| // Dump the AST representation to a dump context. |
| void |
| dump_clause(Ast_dump_context*) const; |
| |
| private: |
| // The type for this type clause. |
| Type* type_; |
| // The statements to execute. |
| Block* statements_; |
| // Whether this falls through--this is true for "case T1, T2". |
| bool is_fallthrough_; |
| // Whether this is the default case. |
| bool is_default_; |
| // The location of this type case clause. |
| Location location_; |
| }; |
| |
| friend class Type_case_clause; |
| |
| // The type of the list of type clauses. |
| typedef std::vector<Type_case_clause> Type_clauses; |
| |
| // All the type case clauses. |
| Type_clauses clauses_; |
| }; |
| |
| // A type switch statement. |
| |
| class Type_switch_statement : public Statement |
| { |
| public: |
| Type_switch_statement(const std::string& name, Expression* expr, |
| Location location) |
| : Statement(STATEMENT_TYPE_SWITCH, location), |
| name_(name), expr_(expr), clauses_(NULL), break_label_(NULL) |
| { } |
| |
| // Add the clauses. |
| void |
| add_clauses(Type_case_clauses* clauses) |
| { |
| go_assert(this->clauses_ == NULL); |
| this->clauses_ = clauses; |
| } |
| |
| // Return the break label for this type switch statement. |
| Unnamed_label* |
| break_label(); |
| |
| protected: |
| int |
| do_traverse(Traverse*); |
| |
| Statement* |
| do_lower(Gogo*, Named_object*, Block*, Statement_inserter*); |
| |
| Bstatement* |
| do_get_backend(Translate_context*) |
| { go_unreachable(); } |
| |
| void |
| do_dump_statement(Ast_dump_context*) const; |
| |
| bool |
| do_may_fall_through() const; |
| |
| private: |
| // The name of the variable declared in the type switch guard. Empty if there |
| // is no variable declared. |
| std::string name_; |
| // The expression we are switching on if there is no variable. |
| Expression* expr_; |
| // The type case clauses. |
| Type_case_clauses* clauses_; |
| // The break label, if needed. |
| Unnamed_label* break_label_; |
| }; |
| |
| #endif // !defined(GO_STATEMENTS_H) |