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// gogo.h -- Go frontend parsed representation. -*- 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_GOGO_H
#define GO_GOGO_H
#include "go-linemap.h"
class Traverse;
class Statement_inserter;
class Type;
class Type_equal;
class Typed_identifier;
class Typed_identifier_list;
class Function_type;
class Expression;
class Expression_list;
class Statement;
class Temporary_statement;
class Block;
class Function;
class Bindings;
class Bindings_snapshot;
class Package;
class Variable;
class Pointer_type;
class Struct_type;
class Struct_field;
class Struct_field_list;
class Array_type;
class Map_type;
class Channel_type;
class Interface_type;
class Named_type;
class Forward_declaration_type;
class Named_object;
class Label;
class Translate_context;
class Backend;
class Export;
class Export_function_body;
class Import;
class Import_function_body;
class Bexpression;
class Btype;
class Bstatement;
class Bblock;
class Bvariable;
class Blabel;
class Bfunction;
class Escape_context;
class Node;
// This file declares the basic classes used to hold the internal
// representation of Go which is built by the parser.
// An initialization function for an imported package. This is a
// magic function which initializes variables and runs the "init"
// function.
class Import_init
{
public:
Import_init(const std::string& package_name, const std::string& init_name,
int priority)
: package_name_(package_name), init_name_(init_name), priority_(priority)
{ }
// The name of the package being imported.
const std::string&
package_name() const
{ return this->package_name_; }
// The name of the package's init function.
const std::string&
init_name() const
{ return this->init_name_; }
// Older V1 export data uses a priority scheme to order
// initialization functions; functions with a lower priority number
// must be run first. This value will be set to -1 for current
// generation objects, and will take on a non-negative value only
// when importing a V1-vintage object.
int
priority() const
{ return this->priority_; }
// Reset priority.
void
set_priority(int new_priority)
{ this->priority_ = new_priority; }
// Record the fact that some other init fcn must be run before this init fcn.
void
record_precursor_fcn(std::string init_fcn_name)
{ this->precursor_functions_.insert(init_fcn_name); }
// Return the list of precursor fcns for this fcn (must be run before it).
const std::set<std::string>&
precursors() const
{ return this->precursor_functions_; }
private:
// The name of the package being imported.
std::string package_name_;
// The name of the package's init function.
std::string init_name_;
// Names of init functions that must be run before this fcn.
std::set<std::string> precursor_functions_;
// Priority for this function. See note above on obsolescence.
int priority_;
};
// For sorting purposes.
struct Import_init_lt {
bool operator()(const Import_init* i1, const Import_init* i2) const
{
return i1->init_name() < i2->init_name();
}
};
// Set of import init objects.
class Import_init_set : public std::set<Import_init*, Import_init_lt> {
};
inline bool
priority_compare(const Import_init* i1, const Import_init* i2)
{
if (i1->priority() < i2->priority())
return true;
if (i1->priority() > i2->priority())
return false;
if (i1->package_name() != i2->package_name())
return i1->package_name() < i2->package_name();
return i1->init_name() < i2->init_name();
}
// The holder for the internal representation of the entire
// compilation unit.
class Gogo
{
public:
// Create the IR, passing in the sizes of the types "int" and
// "uintptr" in bits.
Gogo(Backend* backend, Linemap *linemap, int int_type_size, int pointer_size);
// Get the backend generator.
Backend*
backend()
{ return this->backend_; }
// Get the Location generator.
Linemap*
linemap()
{ return this->linemap_; }
// Get the package name.
const std::string&
package_name() const;
// Set the package name.
void
set_package_name(const std::string&, Location);
// Return whether this is the "main" package.
bool
is_main_package() const;
// If necessary, adjust the name to use for a hidden symbol. We add
// the package name, so that hidden symbols in different packages do
// not collide.
std::string
pack_hidden_name(const std::string& name, bool is_exported) const
{
return (is_exported
? name
: '.' + this->pkgpath() + '.' + name);
}
// Unpack a name which may have been hidden. Returns the
// user-visible name of the object.
static std::string
unpack_hidden_name(const std::string& name)
{ return name[0] != '.' ? name : name.substr(name.rfind('.') + 1); }
// Return whether a possibly packed name is hidden.
static bool
is_hidden_name(const std::string& name)
{ return name[0] == '.'; }
// Return the package path of a hidden name.
static std::string
hidden_name_pkgpath(const std::string& name)
{
go_assert(Gogo::is_hidden_name(name));
return name.substr(1, name.rfind('.') - 1);
}
// Given a name which may or may not have been hidden, append the
// appropriate version of the name to the result string.
static void
append_possibly_hidden_name(std::string *result, const std::string& name);
// Given a name which may or may not have been hidden, return the
// name to use in an error message.
static std::string
message_name(const std::string& name);
// Return whether a name is the blank identifier _.
static bool
is_sink_name(const std::string& name)
{
return (name[0] == '.'
&& name[name.length() - 1] == '_'
&& name[name.length() - 2] == '.');
}
// Convert a pkgpath into a string suitable for a symbol
static std::string
pkgpath_for_symbol(const std::string& pkgpath);
// Return the package path to use for reflect.Type.PkgPath.
const std::string&
pkgpath() const;
// Return the package path to use for a symbol name.
const std::string&
pkgpath_symbol() const;
// Set the package path from a command line option.
void
set_pkgpath(const std::string&);
// Set the prefix from a command line option.
void
set_prefix(const std::string&);
// Return whether pkgpath was set from a command line option.
bool
pkgpath_from_option() const
{ return this->pkgpath_from_option_; }
// Return the relative import path as set from the command line.
// Returns an empty string if it was not set.
const std::string&
relative_import_path() const
{ return this->relative_import_path_; }
// Set the relative import path from a command line option.
void
set_relative_import_path(const std::string& s)
{ this->relative_import_path_ = s; }
// Set the C header file to write. This is used for the runtime
// package.
void
set_c_header(const std::string& s)
{ this->c_header_ = s; }
// Return whether to check for division by zero in binary operations.
bool
check_divide_by_zero() const
{ return this->check_divide_by_zero_; }
// Set the option to check division by zero from a command line option.
void
set_check_divide_by_zero(bool b)
{ this->check_divide_by_zero_ = b; }
// Return whether to check for division overflow in binary operations.
bool
check_divide_overflow() const
{ return this->check_divide_overflow_; }
// Set the option to check division overflow from a command line option.
void
set_check_divide_overflow(bool b)
{ this->check_divide_overflow_ = b; }
// Return whether we are compiling the runtime package.
bool
compiling_runtime() const
{ return this->compiling_runtime_; }
// Set whether we are compiling the runtime package.
void
set_compiling_runtime(bool b)
{ this->compiling_runtime_ = b; }
// Return the level of escape analysis debug information to emit.
int
debug_escape_level() const
{ return this->debug_escape_level_; }
// Set the level of escape analysis debugging from a command line option.
void
set_debug_escape_level(int level)
{ this->debug_escape_level_ = level; }
// Return the hash for debug escape analysis.
std::string
debug_escape_hash() const
{ return this->debug_escape_hash_; }
// Set the hash value for debug escape analysis.
void
set_debug_escape_hash(const std::string& s)
{ this->debug_escape_hash_ = s; }
// Return the size threshold used to determine whether to issue
// a nil-check for a given pointer dereference. A threshold of -1
// implies that all potentially faulting dereference ops should
// be nil-checked. A positive threshold of N implies that a deref
// of *P where P has size less than N doesn't need a nil check.
int64_t
nil_check_size_threshold() const
{ return this->nil_check_size_threshold_; }
// Set the nil-check size threshold, as described above.
void
set_nil_check_size_threshold(int64_t bytes)
{ this->nil_check_size_threshold_ = bytes; }
// Import a package. FILENAME is the file name argument, LOCAL_NAME
// is the local name to give to the package. If LOCAL_NAME is empty
// the declarations are added to the global scope.
void
import_package(const std::string& filename, const std::string& local_name,
bool is_local_name_exported, bool must_exist, Location);
// Whether we are the global binding level.
bool
in_global_scope() const;
// Look up a name in the current binding contours.
Named_object*
lookup(const std::string&, Named_object** pfunction) const;
// Look up a name in the current block.
Named_object*
lookup_in_block(const std::string&) const;
// Look up a name in the global namespace--the universal scope.
Named_object*
lookup_global(const char*) const;
// Add a new imported package. REAL_NAME is the real name of the
// package. ALIAS is the alias of the package; this may be the same
// as REAL_NAME. This sets *PADD_TO_GLOBALS if symbols added to
// this package should be added to the global namespace; this is
// true if the alias is ".". LOCATION is the location of the import
// statement. This returns the new package, or NULL on error.
Package*
add_imported_package(const std::string& real_name, const std::string& alias,
bool is_alias_exported,
const std::string& pkgpath,
const std::string& pkgpath_symbol,
Location location,
bool* padd_to_globals);
// Register a package. This package may or may not be imported.
// This returns the Package structure for the package, creating if
// it necessary.
Package*
register_package(const std::string& pkgpath,
const std::string& pkgpath_symbol, Location);
// Look up a package by pkgpath, and return its pkgpath_symbol.
std::string
pkgpath_symbol_for_package(const std::string&);
// Start compiling a function. ADD_METHOD_TO_TYPE is true if a
// method function should be added to the type of its receiver.
Named_object*
start_function(const std::string& name, Function_type* type,
bool add_method_to_type, Location);
// Finish compiling a function.
void
finish_function(Location);
// Return the current function.
Named_object*
current_function() const;
// Return the current block.
Block*
current_block();
// Start a new block. This is not initially associated with a
// function.
void
start_block(Location);
// Finish the current block and return it.
Block*
finish_block(Location);
// Declare an erroneous name. This is used to avoid knock-on errors
// after a parsing error.
Named_object*
add_erroneous_name(const std::string& name);
// Declare an unknown name. This is used while parsing. The name
// must be resolved by the end of the parse. Unknown names are
// always added at the package level.
Named_object*
add_unknown_name(const std::string& name, Location);
// Declare a function.
Named_object*
declare_function(const std::string&, Function_type*, Location);
// Declare a function at the package level. This is used for
// functions generated for a type.
Named_object*
declare_package_function(const std::string&, Function_type*, Location);
// Add a function declaration to the list of functions we may want
// to inline.
void
add_imported_inlinable_function(Named_object*);
// Add a function to the list of functions that we do want to
// inline.
void
add_imported_inline_function(Named_object* no)
{ this->imported_inline_functions_.push_back(no); }
// Add a label.
Label*
add_label_definition(const std::string&, Location);
// Add a label reference. ISSUE_GOTO_ERRORS is true if we should
// report errors for a goto from the current location to the label
// location.
Label*
add_label_reference(const std::string&, Location,
bool issue_goto_errors);
// An analysis set is a list of functions paired with a boolean that indicates
// whether the list of functions are recursive.
typedef std::pair<std::vector<Named_object*>, bool> Analysis_set;
// Add a GROUP of possibly RECURSIVE functions to the Analysis_set for this
// package.
void
add_analysis_set(const std::vector<Named_object*>& group, bool recursive)
{ this->analysis_sets_.push_back(std::make_pair(group, recursive)); }
// Return a snapshot of the current binding state.
Bindings_snapshot*
bindings_snapshot(Location);
// Add a statement to the current block.
void
add_statement(Statement*);
// Add a block to the current block.
void
add_block(Block*, Location);
// Add a constant.
Named_object*
add_constant(const Typed_identifier&, Expression*, int iota_value);
// Add a type.
void
add_type(const std::string&, Type*, Location);
// Add a named type. This is used for builtin types, and to add an
// imported type to the global scope.
void
add_named_type(Named_type*);
// Declare a type.
Named_object*
declare_type(const std::string&, Location);
// Declare a type at the package level. This is used when the
// parser sees an unknown name where a type name is required.
Named_object*
declare_package_type(const std::string&, Location);
// Define a type which was already declared.
void
define_type(Named_object*, Named_type*);
// Add a variable.
Named_object*
add_variable(const std::string&, Variable*);
// Add a sink--a reference to the blank identifier _.
Named_object*
add_sink();
// Add a type which needs to be verified. This is used for sink
// types, just to give appropriate error messages.
void
add_type_to_verify(Type* type);
// Add a named object to the current namespace. This is used for
// import . "package".
void
add_dot_import_object(Named_object*);
// Add an identifier to the list of names seen in the file block.
void
add_file_block_name(const std::string& name, Location location)
{ this->file_block_names_[name] = location; }
// Add a linkname, from the go:linkname compiler directive. This
// changes the externally visible name of go_name to be ext_name.
void
add_linkname(const std::string& go_name, bool is_exported,
const std::string& ext_name, Location location);
// Mark all local variables in current bindings as used. This is
// used when there is a parse error to avoid useless errors.
void
mark_locals_used();
// Note that we've seen an interface type. This is used to build
// all required interface method tables.
void
record_interface_type(Interface_type*);
// Note that we need an initialization function.
void
set_need_init_fn()
{ this->need_init_fn_ = true; }
// Return whether the current file imported the unsafe package.
bool
current_file_imported_unsafe() const
{ return this->current_file_imported_unsafe_; }
// Clear out all names in file scope. This is called when we start
// parsing a new file.
void
clear_file_scope();
// Record that VAR1 must be initialized after VAR2. This is used
// when VAR2 does not appear in VAR1's INIT or PREINIT.
void
record_var_depends_on(Variable* var1, Named_object* var2)
{
go_assert(this->var_deps_.find(var1) == this->var_deps_.end());
this->var_deps_[var1] = var2;
}
// Return the variable that VAR depends on, or NULL if none.
Named_object*
var_depends_on(Variable* var) const
{
Var_deps::const_iterator p = this->var_deps_.find(var);
return p != this->var_deps_.end() ? p->second : NULL;
}
// Queue up a type-specific function to be written out. This is
// used when a type-specific function is needed when not at the top
// level.
void
queue_specific_type_function(Type* type, Named_type* name, int64_t size,
const std::string& hash_name,
Function_type* hash_fntype,
const std::string& equal_name,
Function_type* equal_fntype);
// Write out queued specific type functions.
void
write_specific_type_functions();
// Whether we are done writing out specific type functions.
bool
specific_type_functions_are_written() const
{ return this->specific_type_functions_are_written_; }
// Add a pointer that needs to be added to the list of objects
// traversed by the garbage collector. This should be an expression
// of pointer type that points to static storage. It's not
// necessary to add global variables to this list, just global
// variable initializers that would otherwise not be seen.
void
add_gc_root(Expression* expr)
{
this->set_need_init_fn();
this->gc_roots_.push_back(expr);
}
// Traverse the tree. See the Traverse class.
void
traverse(Traverse*);
// Define the predeclared global names.
void
define_global_names();
// Verify and complete all types.
void
verify_types();
// Lower the parse tree.
void
lower_parse_tree();
// Lower all the statements in a block.
void
lower_block(Named_object* function, Block*);
// Lower an expression.
void
lower_expression(Named_object* function, Statement_inserter*, Expression**);
// Lower a constant.
void
lower_constant(Named_object*);
// Flatten all the statements in a block.
void
flatten_block(Named_object* function, Block*);
// Flatten an expression.
void
flatten_expression(Named_object* function, Statement_inserter*, Expression**);
// Create all necessary function descriptors.
void
create_function_descriptors();
// Finalize the method lists and build stub methods for named types.
void
finalize_methods();
// Finalize the method list for one type.
void
finalize_methods_for_type(Type*);
// Work out the types to use for unspecified variables and
// constants.
void
determine_types();
// Type check the program.
void
check_types();
// Check the types in a single block. This is used for complicated
// go statements.
void
check_types_in_block(Block*);
// Check for return statements.
void
check_return_statements();
// Analyze the program flow for escape information.
void
analyze_escape();
// Discover the groups of possibly recursive functions in this package.
void
discover_analysis_sets();
// Build a connectivity graph between the objects in each analyzed function.
void
assign_connectivity(Escape_context*, Named_object*);
// Traverse the objects in the connecitivty graph from the sink, adjusting the
// escape levels of each object.
void
propagate_escape(Escape_context*, Node*);
// Add notes about the escape level of a function's input and output
// parameters for exporting and importing top level functions.
void
tag_function(Escape_context*, Named_object*);
// Reclaim memory of escape analysis Nodes.
void
reclaim_escape_nodes();
// Do all exports.
void
do_exports();
// Add an import control function for an imported package to the
// list.
void
add_import_init_fn(const std::string& package_name,
const std::string& init_name, int prio);
// Return the Import_init for a given init name.
Import_init*
lookup_init(const std::string& init_name);
// Turn short-cut operators (&&, ||) into explicit if statements.
void
remove_shortcuts();
// Use temporary variables to force order of evaluation.
void
order_evaluations();
// Add write barriers as needed.
void
add_write_barriers();
// Return whether an assignment that sets LHS to RHS needs a write
// barrier.
bool
assign_needs_write_barrier(Expression* lhs);
// Return an assignment that sets LHS to RHS using a write barrier.
// This returns an if statement that checks whether write barriers
// are enabled. If not, it does LHS = RHS, otherwise it calls the
// appropriate write barrier function.
Statement*
assign_with_write_barrier(Function*, Block*, Statement_inserter*,
Expression* lhs, Expression* rhs, Location);
// Flatten parse tree.
void
flatten();
// Build thunks for functions which call recover.
void
build_recover_thunks();
// Return a declaration for __builtin_return_address or
// __builtin_frame_address.
static Named_object*
declare_builtin_rf_address(const char* name);
// Simplify statements which might use thunks: go and defer
// statements.
void
simplify_thunk_statements();
// Dump AST if -fgo-dump-ast is set.
void
dump_ast(const char* basename);
// Dump Call Graph if -fgo-dump-calls is set.
void
dump_call_graph(const char* basename);
// Dump Connection Graphs if -fgo-dump-connections is set.
void
dump_connection_graphs(const char* basename);
// Convert named types to the backend representation.
void
convert_named_types();
// Convert named types in a list of bindings.
void
convert_named_types_in_bindings(Bindings*);
// True if named types have been converted to the backend
// representation.
bool
named_types_are_converted() const
{ return this->named_types_are_converted_; }
// Give an error if the initialization of VAR depends on itself.
void
check_self_dep(Named_object*);
// Write out the global values.
void
write_globals();
// Build a call to the runtime error function.
Expression*
runtime_error(int code, Location);
// Build required interface method tables.
void
build_interface_method_tables();
// Return an expression which allocates memory to hold values of type TYPE.
Expression*
allocate_memory(Type *type, Location);
// Return the assembler name to use for an exported function, a
// method, or a function/method declaration.
std::string
function_asm_name(const std::string& go_name, const Package*,
const Type* receiver);
// Return the name to use for a function descriptor.
std::string
function_descriptor_name(Named_object*);
// Return the name to use for a generated stub method.
std::string
stub_method_name(const Package*, const std::string& method_name);
// Return the names of the hash and equality functions for TYPE.
void
specific_type_function_names(const Type*, const Named_type*,
std::string* hash_name,
std::string* equal_name);
// Return the assembler name to use for a global variable.
std::string
global_var_asm_name(const std::string& go_name, const Package*);
// Return a name to use for an error case. This should only be used
// after reporting an error, and is used to avoid useless knockon
// errors.
static std::string
erroneous_name();
// Return whether the name indicates an error.
static bool
is_erroneous_name(const std::string&);
// Return a name to use for a thunk function. A thunk function is
// one we create during the compilation, for a go statement or a
// defer statement or a method expression.
std::string
thunk_name();
// Return whether an object is a thunk.
static bool
is_thunk(const Named_object*);
// Return the name to use for an init function.
std::string
init_function_name();
// Return the name to use for a nested function.
std::string
nested_function_name(Named_object* enclosing);
// Return the name to use for a sink funciton.
std::string
sink_function_name();
// Return the name to use for an (erroneous) redefined function.
std::string
redefined_function_name();
// Return the name for use for a recover thunk.
std::string
recover_thunk_name(const std::string& name, const Type* rtype);
// Return the name to use for the GC root variable.
std::string
gc_root_name();
// Return the name to use for a composite literal or string
// initializer.
std::string
initializer_name();
// Return the name of the variable used to represent the zero value
// of a map.
std::string
map_zero_value_name();
// Get the name of the magic initialization function.
const std::string&
get_init_fn_name();
// Return the name for a type descriptor symbol.
std::string
type_descriptor_name(Type*, Named_type*);
// Return the assembler name for the GC symbol for a type.
std::string
gc_symbol_name(Type*);
// Return the assembler name for a ptrmask variable.
std::string
ptrmask_symbol_name(const std::string& ptrmask_sym_name);
// Return the name to use for an interface method table.
std::string
interface_method_table_name(Interface_type*, Type*, bool is_pointer);
// Return whether NAME is a special name that can not be passed to
// unpack_hidden_name. This is needed because various special names
// use "..SUFFIX", but unpack_hidden_name just looks for '.'.
static bool
is_special_name(const std::string& name);
private:
// During parsing, we keep a stack of functions. Each function on
// the stack is one that we are currently parsing. For each
// function, we keep track of the current stack of blocks.
struct Open_function
{
// The function.
Named_object* function;
// The stack of active blocks in the function.
std::vector<Block*> blocks;
};
// The stack of functions.
typedef std::vector<Open_function> Open_functions;
// Set up the built-in unsafe package.
void
import_unsafe(const std::string&, bool is_exported, Location);
// Return the current binding contour.
Bindings*
current_bindings();
const Bindings*
current_bindings() const;
void
write_c_header();
// Get the decl for the magic initialization function.
Named_object*
initialization_function_decl();
// Create the magic initialization function.
Named_object*
create_initialization_function(Named_object* fndecl, Bstatement* code_stmt);
// Initialize imported packages. BFUNCTION is the function
// into which the package init calls will be placed.
void
init_imports(std::vector<Bstatement*>&, Bfunction* bfunction);
// Register variables with the garbage collector.
void
register_gc_vars(const std::vector<Named_object*>&,
std::vector<Bstatement*>&,
Bfunction* init_bfunction);
void
propagate_writebarrierrec();
Named_object*
write_barrier_variable();
Statement*
check_write_barrier(Block*, Statement*, Statement*);
// Type used to map import names to packages.
typedef std::map<std::string, Package*> Imports;
// Type used to map package names to packages.
typedef std::map<std::string, Package*> Packages;
// Type used to map variables to the function calls that set them.
// This is used for initialization dependency analysis.
typedef std::map<Variable*, Named_object*> Var_deps;
// Type used to map identifiers in the file block to the location
// where they were defined.
typedef Unordered_map(std::string, Location) File_block_names;
// Type used to queue writing a type specific function.
struct Specific_type_function
{
Type* type;
Named_type* name;
int64_t size;
std::string hash_name;
Function_type* hash_fntype;
std::string equal_name;
Function_type* equal_fntype;
Specific_type_function(Type* atype, Named_type* aname, int64_t asize,
const std::string& ahash_name,
Function_type* ahash_fntype,
const std::string& aequal_name,
Function_type* aequal_fntype)
: type(atype), name(aname), size(asize), hash_name(ahash_name),
hash_fntype(ahash_fntype), equal_name(aequal_name),
equal_fntype(aequal_fntype)
{ }
};
// Recompute init priorities.
void
recompute_init_priorities();
// Recursive helper used by the routine above.
void
update_init_priority(Import_init* ii,
std::set<const Import_init *>* visited);
// The backend generator.
Backend* backend_;
// The object used to keep track of file names and line numbers.
Linemap* linemap_;
// The package we are compiling.
Package* package_;
// The list of currently open functions during parsing.
Open_functions functions_;
// The global binding contour. This includes the builtin functions
// and the package we are compiling.
Bindings* globals_;
// The list of names we have seen in the file block.
File_block_names file_block_names_;
// Mapping from import file names to packages.
Imports imports_;
// Whether the magic unsafe package was imported.
bool imported_unsafe_;
// Whether the magic unsafe package was imported by the current file.
bool current_file_imported_unsafe_;
// Mapping from package names we have seen to packages. This does
// not include the package we are compiling.
Packages packages_;
// The functions named "init", if there are any.
std::vector<Named_object*> init_functions_;
// A mapping from variables to the function calls that initialize
// them, if it is not stored in the variable's init or preinit.
// This is used for dependency analysis.
Var_deps var_deps_;
// Whether we need a magic initialization function.
bool need_init_fn_;
// The name of the magic initialization function.
std::string init_fn_name_;
// A list of import control variables for packages that we import.
Import_init_set imported_init_fns_;
// The package path used for reflection data.
std::string pkgpath_;
// The package path to use for a symbol name.
std::string pkgpath_symbol_;
// The prefix to use for symbols, from the -fgo-prefix option.
std::string prefix_;
// Whether pkgpath_ has been set.
bool pkgpath_set_;
// Whether an explicit package path was set by -fgo-pkgpath.
bool pkgpath_from_option_;
// Whether an explicit prefix was set by -fgo-prefix.
bool prefix_from_option_;
// The relative import path, from the -fgo-relative-import-path
// option.
std::string relative_import_path_;
// The C header file to write, from the -fgo-c-header option.
std::string c_header_;
// Whether or not to check for division by zero, from the
// -fgo-check-divide-zero option.
bool check_divide_by_zero_;
// Whether or not to check for division overflow, from the
// -fgo-check-divide-overflow option.
bool check_divide_overflow_;
// Whether we are compiling the runtime package, from the
// -fgo-compiling-runtime option.
bool compiling_runtime_;
// The level of escape analysis debug information to emit, from the
// -fgo-debug-escape option.
int debug_escape_level_;
// A hash value for debug escape analysis, from the
// -fgo-debug-escape-hash option. The analysis is run only on
// functions with names that hash to the matching value.
std::string debug_escape_hash_;
// Nil-check size threshhold.
int64_t nil_check_size_threshold_;
// A list of types to verify.
std::vector<Type*> verify_types_;
// A list of interface types defined while parsing.
std::vector<Interface_type*> interface_types_;
// Type specific functions to write out.
std::vector<Specific_type_function*> specific_type_functions_;
// Whether we are done writing out specific type functions.
bool specific_type_functions_are_written_;
// Whether named types have been converted.
bool named_types_are_converted_;
// A list containing groups of possibly mutually recursive functions to be
// considered during escape analysis.
std::vector<Analysis_set> analysis_sets_;
// A list of objects to add to the GC roots.
std::vector<Expression*> gc_roots_;
// A list of function declarations with imported bodies that we may
// want to inline.
std::vector<Named_object*> imported_inlinable_functions_;
// A list of functions that we want to inline. These will be sent
// to the backend.
std::vector<Named_object*> imported_inline_functions_;
};
// A block of statements.
class Block
{
public:
Block(Block* enclosing, Location);
// Return the enclosing block.
const Block*
enclosing() const
{ return this->enclosing_; }
// Return the bindings of the block.
Bindings*
bindings()
{ return this->bindings_; }
const Bindings*
bindings() const
{ return this->bindings_; }
// Look at the block's statements.
const std::vector<Statement*>*
statements() const
{ return &this->statements_; }
// Return the start location. This is normally the location of the
// left curly brace which starts the block.
Location
start_location() const
{ return this->start_location_; }
// Return the end location. This is normally the location of the
// right curly brace which ends the block.
Location
end_location() const
{ return this->end_location_; }
// Add a statement to the block.
void
add_statement(Statement*);
// Add a statement to the front of the block.
void
add_statement_at_front(Statement*);
// Replace a statement in a block.
void
replace_statement(size_t index, Statement*);
// Add a Statement before statement number INDEX.
void
insert_statement_before(size_t index, Statement*);
// Add a Statement after statement number INDEX.
void
insert_statement_after(size_t index, Statement*);
// Set the end location of the block.
void
set_end_location(Location location)
{ this->end_location_ = location; }
// Traverse the tree.
int
traverse(Traverse*);
// Set final types for unspecified variables and constants.
void
determine_types();
// Return true if execution of this block may fall through to the
// next block.
bool
may_fall_through() const;
// Write the export data for the block's statements to the string.
void
export_block(Export_function_body*);
// Turn exported block data into a block.
static bool
import_block(Block*, Import_function_body*, Location);
// Convert the block to the backend representation.
Bblock*
get_backend(Translate_context*);
// Iterate over statements.
typedef std::vector<Statement*>::iterator iterator;
iterator
begin()
{ return this->statements_.begin(); }
iterator
end()
{ return this->statements_.end(); }
private:
// Enclosing block.
Block* enclosing_;
// Statements in the block.
std::vector<Statement*> statements_;
// Binding contour.
Bindings* bindings_;
// Location of start of block.
Location start_location_;
// Location of end of block.
Location end_location_;
};
// A function.
class Function
{
public:
Function(Function_type* type, Named_object*, Block*, Location);
// Return the function's type.
Function_type*
type() const
{ return this->type_; }
// Return the enclosing function if there is one.
Named_object*
enclosing() const
{ return this->enclosing_; }
// Set the enclosing function. This is used when building thunks
// for functions which call recover.
void
set_enclosing(Named_object* enclosing)
{
go_assert(this->enclosing_ == NULL);
this->enclosing_ = enclosing;
}
// The result variables.
typedef std::vector<Named_object*> Results;
// Create the result variables in the outer block.
void
create_result_variables(Gogo*);
// Update the named result variables when cloning a function which
// calls recover.
void
update_result_variables();
// Return the result variables.
Results*
result_variables()
{ return this->results_; }
bool
is_sink() const
{ return this->is_sink_; }
void
set_is_sink()
{ this->is_sink_ = true; }
// Whether the result variables have names.
bool
results_are_named() const
{ return this->results_are_named_; }
// Return the assembler name.
const std::string&
asm_name() const
{ return this->asm_name_; }
// Set the assembler name.
void
set_asm_name(const std::string& asm_name)
{ this->asm_name_ = asm_name; }
// Return the pragmas for this function.
unsigned int
pragmas() const
{ return this->pragmas_; }
// Set the pragmas for this function.
void
set_pragmas(unsigned int pragmas)
{
this->pragmas_ = pragmas;
}
// Return the index to use for a nested function.
unsigned int
next_nested_function_index()
{
++this->nested_functions_;
return this->nested_functions_;
}
// Whether this method should not be included in the type
// descriptor.
bool
nointerface() const;
// Record that this method should not be included in the type
// descriptor.
void
set_nointerface();
// Record that this function is a stub method created for an unnamed
// type.
void
set_is_unnamed_type_stub_method()
{
go_assert(this->is_method());
this->is_unnamed_type_stub_method_ = true;
}
// Return the amount of enclosed variables in this closure.
size_t
closure_field_count() const
{ return this->closure_fields_.size(); }
// Add a new field to the closure variable.
void
add_closure_field(Named_object* var, Location loc)
{ this->closure_fields_.push_back(std::make_pair(var, loc)); }
// Whether this function needs a closure.
bool
needs_closure() const
{ return !this->closure_fields_.empty(); }
// Return the closure variable, creating it if necessary. This is
// passed to the function as a static chain parameter.
Named_object*
closure_var();
// Set the closure variable. This is used when building thunks for
// functions which call recover.
void
set_closure_var(Named_object* v)
{
go_assert(this->closure_var_ == NULL);
this->closure_var_ = v;
}
// Return the variable for a reference to field INDEX in the closure
// variable.
Named_object*
enclosing_var(unsigned int index)
{
go_assert(index < this->closure_fields_.size());
return closure_fields_[index].first;
}
// Set the type of the closure variable if there is one.
void
set_closure_type();
// Get the block of statements associated with the function.
Block*
block() const
{ return this->block_; }
// Get the location of the start of the function.
Location
location() const
{ return this->location_; }
// Return whether this function is actually a method.
bool
is_method() const;
// Add a label definition to the function.
Label*
add_label_definition(Gogo*, const std::string& label_name, Location);
// Add a label reference to a function. ISSUE_GOTO_ERRORS is true
// if we should report errors for a goto from the current location
// to the label location.
Label*
add_label_reference(Gogo*, const std::string& label_name,
Location, bool issue_goto_errors);
// Warn about labels that are defined but not used.
void
check_labels() const;
// Note that a new local type has been added. Return its index.
unsigned int
new_local_type_index()
{ return this->local_type_count_++; }
// Whether this function calls the predeclared recover function.
bool
calls_recover() const
{ return this->calls_recover_; }
// Record that this function calls the predeclared recover function.
// This is set during the lowering pass.
void
set_calls_recover()
{ this->calls_recover_ = true; }
// Whether this is a recover thunk function.
bool
is_recover_thunk() const
{ return this->is_recover_thunk_; }
// Record that this is a thunk built for a function which calls
// recover.
void
set_is_recover_thunk()
{ this->is_recover_thunk_ = true; }
// Whether this function already has a recover thunk.
bool
has_recover_thunk() const
{ return this->has_recover_thunk_; }
// Record that this function already has a recover thunk.
void
set_has_recover_thunk()
{ this->has_recover_thunk_ = true; }
// Record that this function is a thunk created for a defer
// statement that calls the __go_set_defer_retaddr runtime function.
void
set_calls_defer_retaddr()
{ this->calls_defer_retaddr_ = true; }
// Whether this is a type hash or equality function created by the
// compiler.
bool
is_type_specific_function()
{ return this->is_type_specific_function_; }
// Record that this function is a type hash or equality function
// created by the compiler.
void
set_is_type_specific_function()
{ this->is_type_specific_function_ = true; }
// Mark the function as going into a unique section.
void
set_in_unique_section()
{ this->in_unique_section_ = true; }
// Return whether this function should be exported for inlining.
bool
export_for_inlining() const
{ return this->export_for_inlining_; }
// Mark the function to be exported for inlining.
void
set_export_for_inlining()
{ this->export_for_inlining_ = true; }
// Return whether this function is inline only.
bool
is_inline_only() const
{ return this->is_inline_only_; }
// Mark the function as inline only: the body should not be emitted
// if it is not inlined.
void
set_is_inline_only()
{ this->is_inline_only_ = true; }
// Swap with another function. Used only for the thunk which calls
// recover.
void
swap_for_recover(Function *);
// Traverse the tree.
int
traverse(Traverse*);
// Determine types in the function.
void
determine_types();
// Return an expression for the function descriptor, given the named
// object for this function. This may only be called for functions
// without a closure. This will be an immutable struct with one
// field that points to the function's code.
Expression*
descriptor(Gogo*, Named_object*);
// Set the descriptor for this function. This is used when a
// function declaration is followed by a function definition.
void
set_descriptor(Expression* descriptor)
{
go_assert(this->descriptor_ == NULL);
this->descriptor_ = descriptor;
}
// Return the backend representation.
Bfunction*
get_or_make_decl(Gogo*, Named_object*);
// Return the function's decl after it has been built.
Bfunction*
get_decl() const;
// Set the function decl to hold a backend representation of the function
// code.
void
build(Gogo*, Named_object*);
// Get the statement that assigns values to this function's result struct.
Bstatement*
return_value(Gogo*, Named_object*, Location) const;
// Get an expression for the variable holding the defer stack.
Expression*
defer_stack(Location);
// Export the function.
void
export_func(Export*, const std::string& name) const;
// Export a function with a type.
static void
export_func_with_type(Export*, const std::string& name,
const Function_type*, Results*, bool nointerface,
Block* block, Location);
// Import a function.
static void
import_func(Import*, std::string* pname, Typed_identifier** receiver,
Typed_identifier_list** pparameters,
Typed_identifier_list** presults, bool* is_varargs,
bool* nointerface, std::string* body);
private:
// Type for mapping from label names to Label objects.
typedef Unordered_map(std::string, Label*) Labels;
void
build_defer_wrapper(Gogo*, Named_object*, Bstatement**, Bstatement**);
typedef std::vector<std::pair<Named_object*,
Location> > Closure_fields;
// The function's type.
Function_type* type_;
// The enclosing function. This is NULL when there isn't one, which
// is the normal case.
Named_object* enclosing_;
// The result variables, if any.
Results* results_;
// If there is a closure, this is the list of variables which appear
// in the closure. This is created by the parser, and then resolved
// to a real type when we lower parse trees.
Closure_fields closure_fields_;
// The closure variable, passed as a parameter using the static
// chain parameter. Normally NULL.
Named_object* closure_var_;
// The outer block of statements in the function.
Block* block_;
// The source location of the start of the function.
Location location_;
// Labels defined or referenced in the function.
Labels labels_;
// The number of local types defined in this function.
unsigned int local_type_count_;
// The assembler name: this is the name that will be put in the object file.
// Set by the go:linkname compiler directive. This is normally empty.
std::string asm_name_;
// The function descriptor, if any.
Expression* descriptor_;
// The function decl.
Bfunction* fndecl_;
// The defer stack variable. A pointer to this variable is used to
// distinguish the defer stack for one function from another. This
// is NULL unless we actually need a defer stack.
Temporary_statement* defer_stack_;
// Pragmas for this function. This is a set of GOPRAGMA bits.
unsigned int pragmas_;
// Number of nested functions defined within this function.
unsigned int nested_functions_;
// True if this function is sink-named. No code is generated.
bool is_sink_ : 1;
// True if the result variables are named.
bool results_are_named_ : 1;
// True if this function is a stub method created for an unnamed
// type.
bool is_unnamed_type_stub_method_ : 1;
// True if this function calls the predeclared recover function.
bool calls_recover_ : 1;
// True if this a thunk built for a function which calls recover.
bool is_recover_thunk_ : 1;
// True if this function already has a recover thunk.
bool has_recover_thunk_ : 1;
// True if this is a thunk built for a defer statement that calls
// the __go_set_defer_retaddr runtime function.
bool calls_defer_retaddr_ : 1;
// True if this is a function built by the compiler to as a hash or
// equality function for some type.
bool is_type_specific_function_ : 1;
// True if this function should be put in a unique section. This is
// turned on for field tracking.
bool in_unique_section_ : 1;
// True if we should export the body of this function for
// cross-package inlining.
bool export_for_inlining_ : 1;
// True if this function is inline only: if it should not be emitted
// if it is not inlined.
bool is_inline_only_ : 1;
};
// A snapshot of the current binding state.
class Bindings_snapshot
{
public:
Bindings_snapshot(const Block*, Location);
// Report any errors appropriate for a goto from the current binding
// state of B to this one.
void
check_goto_from(const Block* b, Location);
// Report any errors appropriate for a goto from this binding state
// to the current state of B.
void
check_goto_to(const Block* b);
private:
bool
check_goto_block(Location, const Block*, const Block*, size_t*);
void
check_goto_defs(Location, const Block*, size_t, size_t);
// The current block.
const Block* block_;
// The number of names currently defined in each open block.
// Element 0 is this->block_, element 1 is
// this->block_->enclosing(), etc.
std::vector<size_t> counts_;
// The location where this snapshot was taken.
Location location_;
};
// A function declaration.
class Function_declaration
{
public:
Function_declaration(Function_type* fntype, Location location)
: fntype_(fntype), location_(location), asm_name_(), descriptor_(NULL),
fndecl_(NULL), pragmas_(0), imported_body_(),
is_on_inlinable_list_(false)
{ }
Function_type*
type() const
{ return this->fntype_; }
Location
location() const
{ return this->location_; }
// Return whether this function declaration is a method.
bool
is_method() const;
const std::string&
asm_name() const
{ return this->asm_name_; }
// Set the assembler name.
void
set_asm_name(const std::string& asm_name)
{ this->asm_name_ = asm_name; }
// Return the pragmas for this function.
unsigned int
pragmas() const
{ return this->pragmas_; }
// Set the pragmas for this function.
void
set_pragmas(unsigned int pragmas)
{
this->pragmas_ = pragmas;
}
// Whether this method should not be included in the type
// descriptor.
bool
nointerface() const;
// Record that this method should not be included in the type
// descriptor.
void
set_nointerface();
// Whether we have an imported function body.
bool
has_imported_body() const
{ return !this->imported_body_.empty(); }
// Record the imported body of this function.
void
set_imported_body(Import* imp, const std::string& imported_body)
{
this->imp_ = imp;
this->imported_body_ = imported_body;
}
// Whether this declaration is on the list of inlinable functions.
bool
is_on_inlinable_list() const
{ return this->is_on_inlinable_list_; }
// Set that this function is on the list of inlinable functions.
void
set_is_on_inlinable_list()
{ this->is_on_inlinable_list_ = true; }
// Import the function body, creating a function.
void
import_function_body(Gogo*, Named_object*);
// Return an expression for the function descriptor, given the named
// object for this function. This may only be called for functions
// without a closure. This will be an immutable struct with one
// field that points to the function's code.
Expression*
descriptor(Gogo*, Named_object*);
// Return true if we have created a descriptor for this declaration.
bool
has_descriptor() const
{ return this->descriptor_ != NULL; }
// Return a backend representation.
Bfunction*
get_or_make_decl(Gogo*, Named_object*);
// If there is a descriptor, build it into the backend
// representation.
void
build_backend_descriptor(Gogo*);
// Export a function declaration.
void
export_func(Export* exp, const std::string& name) const
{
Function::export_func_with_type(exp, name, this->fntype_, NULL,
this->is_method() && this->nointerface(),
NULL, this->location_);
}
// Check that the types used in this declaration's signature are defined.
void
check_types() const;
private:
// The type of the function.
Function_type* fntype_;
// The location of the declaration.
Location location_;
// The assembler name: this is the name to use in references to the
// function. This is normally empty.
std::string asm_name_;
// The function descriptor, if any.
Expression* descriptor_;
// The function decl if needed.
Bfunction* fndecl_;
// Pragmas for this function. This is a set of GOPRAGMA bits.
unsigned int pragmas_;
// Importer for function body if imported from a different package.
Import* imp_;
// Export data for function body if imported from a different package.
std::string imported_body_;
// Whether this declaration is already on the list of inlinable functions.
bool is_on_inlinable_list_;
};
// A variable.
class Variable
{
public:
Variable(Type*, Expression*, bool is_global, bool is_parameter,
bool is_receiver, Location);
// Get the type of the variable.
Type*
type();
Type*
type() const;
// Return whether the type is defined yet.
bool
has_type() const;
// Get the initial value.
Expression*
init() const
{ return this->init_; }
// Return whether there are any preinit statements.
bool
has_pre_init() const
{ return this->preinit_ != NULL; }
// Return the preinit statements if any.
Block*
preinit() const
{ return this->preinit_; }
// Return whether this is a global variable.
bool
is_global() const
{ return this->is_global_; }
// Return whether this is a function parameter.
bool
is_parameter() const
{ return this->is_parameter_; }
// Return whether this is a closure (static chain) parameter.
bool
is_closure() const
{ return this->is_closure_; }
// Change this parameter to be a closure.
void
set_is_closure()
{
this->is_closure_ = true;
}
// Return whether this is the receiver parameter of a method.
bool
is_receiver() const
{ return this->is_receiver_; }
// Change this parameter to be a receiver. This is used when
// creating the thunks created for functions which call recover.
void
set_is_receiver()
{
go_assert(this->is_parameter_);
this->is_receiver_ = true;
}
// Change this parameter to not be a receiver. This is used when
// creating the thunks created for functions which call recover.
void
set_is_not_receiver()
{
go_assert(this->is_parameter_);
this->is_receiver_ = false;
}
// Return whether this is the varargs parameter of a function.
bool
is_varargs_parameter() const
{ return this->is_varargs_parameter_; }
// Whether this variable's address is taken.
bool
is_address_taken() const
{ return this->is_address_taken_; }
// Whether this variable should live in the heap.
bool
is_in_heap() const
{
return this->is_address_taken_
&& this->escapes_
&& !this->is_global_;
}
// Note that something takes the address of this variable.
void
set_address_taken()
{ this->is_address_taken_ = true; }
// Return whether the address is taken but does not escape.
bool
is_non_escaping_address_taken() const
{ return this->is_non_escaping_address_taken_; }
// Note that something takes the address of this variable such that
// the address does not escape the function.
void
set_non_escaping_address_taken()
{ this->is_non_escaping_address_taken_ = true; }
// Return whether this variable escapes the function it is declared in.
bool
escapes()
{ return this->escapes_; }
// Note that this variable does not escape the function it is declared in.
void
set_does_not_escape()
{ this->escapes_ = false; }
// Get the source location of the variable's declaration.
Location
location() const
{ return this->location_; }
// Record that this is the varargs parameter of a function.
void
set_is_varargs_parameter()
{
go_assert(this->is_parameter_);
this->is_varargs_parameter_ = true;
}
// Return whether the variable has been used.
bool
is_used() const
{ return this->is_used_; }
// Mark that the variable has been used.
void
set_is_used()
{ this->is_used_ = true; }
// Clear the initial value; used for error handling and write barriers.
void
clear_init()
{ this->init_ = NULL; }
// Set the initial value; used for converting shortcuts.
void
set_init(Expression* init)
{ this->init_ = init; }
// Get the preinit block, a block of statements to be run before the
// initialization expression.
Block*
preinit_block(Gogo*);
// Add a statement to be run before the initialization expression.
// This is only used for global variables.
void
add_preinit_statement(Gogo*, Statement*);
// Lower the initialization expression after parsing is complete.
void
lower_init_expression(Gogo*, Named_object*, Statement_inserter*);
// Flatten the initialization expression after ordering evaluations.
void
flatten_init_expression(Gogo*, Named_object*, Statement_inserter*);
// A special case: the init value is used only to determine the
// type. This is used if the variable is defined using := with the
// comma-ok form of a map index or a receive expression. The init
// value is actually the map index expression or receive expression.
// We use this because we may not know the right type at parse time.
void
set_type_from_init_tuple()
{ this->type_from_init_tuple_ = true; }
// Another special case: the init value is used only to determine
// the type. This is used if the variable is defined using := with
// a range clause. The init value is the range expression. The
// type of the variable is the index type of the range expression
// (i.e., the first value returned by a range).
void
set_type_from_range_index()
{ this->type_from_range_index_ = true; }
// Another special case: like set_type_from_range_index, but the
// type is the value type of the range expression (i.e., the second
// value returned by a range).
void
set_type_from_range_value()
{ this->type_from_range_value_ = true; }
// Another special case: the init value is used only to determine
// the type. This is used if the variable is defined using := with
// a case in a select statement. The init value is the channel.
// The type of the variable is the channel's element type.
void
set_type_from_chan_element()
{ this->type_from_chan_element_ = true; }
// After we lower the select statement, we once again set the type
// from the initialization expression.
void
clear_type_from_chan_element()
{
go_assert(this->type_from_chan_element_);
this->type_from_chan_element_ = false;
}
// TRUE if this variable was created for a type switch clause.
bool
is_type_switch_var() const
{ return this->is_type_switch_var_; }
// Note that this variable was created for a type switch clause.
void
set_is_type_switch_var()
{ this->is_type_switch_var_ = true; }
// Mark the variable as going into a unique section.
void
set_in_unique_section()
{
go_assert(this->is_global_);
this->in_unique_section_ = true;
}
// Return the top-level declaration for this variable.
Statement*
toplevel_decl()
{ return this->toplevel_decl_; }
// Set the top-level declaration for this variable. Only used for local
// variables
void
set_toplevel_decl(Statement* s)
{
go_assert(!this->is_global_ && !this->is_parameter_ && !this->is_receiver_);
this->toplevel_decl_ = s;
}
// Traverse the initializer expression.
int
traverse_expression(Traverse*, unsigned int traverse_mask);
// Determine the type of the variable if necessary.
void
determine_type();
// Get the backend representation of the variable.
Bvariable*
get_backend_variable(Gogo*, Named_object*, const Package*,
const std::string&);
// Get the initial value of the variable. This may only
// be called if has_pre_init() returns false.
Bexpression*
get_init(Gogo*, Named_object* function);
// Return a series of statements which sets the value of the
// variable in DECL. This should only be called is has_pre_init()
// returns true. DECL may be NULL for a sink variable.
Bstatement*
get_init_block(Gogo*, Named_object* function, Bvariable* decl);
// Export the variable.
void
export_var(Export*, const std::string& name) const;
// Import a variable.
static void
import_var(Import*, std::string* pname, Type** ptype);
private:
// The type of a tuple.
Type*
type_from_tuple(Expression*, bool) const;
// The type of a range.
Type*
type_from_range(Expression*, bool, bool) const;
// The element type of a channel.
Type*
type_from_chan_element(Expression*, bool) const;
// The variable's type. This may be NULL if the type is set from
// the expression.
Type* type_;
// The initial value. This may be NULL if the variable should be
// initialized to the default value for the type.
Expression* init_;
// Statements to run before the init statement.
Block* preinit_;
// Location of variable definition.
Location location_;
// Backend representation.
Bvariable* backend_;
// Whether this is a global variable.
bool is_global_ : 1;
// Whether this is a function parameter.
bool is_parameter_ : 1;
// Whether this is a closure parameter.
bool is_closure_ : 1;
// Whether this is the receiver parameter of a method.
bool is_receiver_ : 1;
// Whether this is the varargs parameter of a function.
bool is_varargs_parameter_ : 1;
// Whether this variable is ever referenced.
bool is_used_ : 1;
// Whether something takes the address of this variable. For a
// local variable this implies that the variable has to be on the
// heap if it escapes from its function.
bool is_address_taken_ : 1;
// Whether something takes the address of this variable such that
// the address does not escape the function.
bool is_non_escaping_address_taken_ : 1;
// True if we have seen this variable in a traversal.
bool seen_ : 1;
// True if we have lowered the initialization expression.
bool init_is_lowered_ : 1;
// True if we have flattened the initialization expression.
bool init_is_flattened_ : 1;
// True if init is a tuple used to set the type.
bool type_from_init_tuple_ : 1;
// True if init is a range clause and the type is the index type.
bool type_from_range_index_ : 1;
// True if init is a range clause and the type is the value type.
bool type_from_range_value_ : 1;
// True if init is a channel and the type is the channel's element type.
bool type_from_chan_element_ : 1;
// True if this is a variable created for a type switch case.
bool is_type_switch_var_ : 1;
// True if we have determined types.
bool determined_type_ : 1;
// True if this variable should be put in a unique section. This is
// used for field tracking.
bool in_unique_section_ : 1;
// Whether this variable escapes the function it is created in. This is
// true until shown otherwise.
bool escapes_ : 1;
// The top-level declaration for this variable. Only used for local
// variables. Must be a Temporary_statement if not NULL.
Statement* toplevel_decl_;
};
// A variable which is really the name for a function return value, or
// part of one.
class Result_variable
{
public:
Result_variable(Type* type, Function* function, int index,
Location location)
: type_(type), function_(function), index_(index), location_(location),
backend_(NULL), is_address_taken_(false),
is_non_escaping_address_taken_(false), escapes_(true)
{ }
// Get the type of the result variable.
Type*
type() const
{ return this->type_; }
// Get the function that this is associated with.
Function*
function() const
{ return this->function_; }
// Index in the list of function results.
int
index() const
{ return this->index_; }
// The location of the variable definition.
Location
location() const
{ return this->location_; }
// Whether this variable's address is taken.
bool
is_address_taken() const
{ return this->is_address_taken_; }
// Note that something takes the address of this variable.
void
set_address_taken()
{ this->is_address_taken_ = true; }
// Return whether the address is taken but does not escape.
bool
is_non_escaping_address_taken() const
{ return this->is_non_escaping_address_taken_; }
// Note that something takes the address of this variable such that
// the address does not escape the function.
void
set_non_escaping_address_taken()
{ this->is_non_escaping_address_taken_ = true; }
// Return whether this variable escapes the function it is declared in.
bool
escapes()
{ return this->escapes_; }
// Note that this variable does not escape the function it is declared in.
void
set_does_not_escape()
{ this->escapes_ = false; }
// Whether this variable should live in the heap.
bool
is_in_heap() const
{
return this->is_address_taken_
&& this->escapes_;
}
// Set the function. This is used when cloning functions which call
// recover.
void
set_function(Function* function)
{ this->function_ = function; }
// Get the backend representation of the variable.
Bvariable*
get_backend_variable(Gogo*, Named_object*, const std::string&);
private:
// Type of result variable.
Type* type_;
// Function with which this is associated.
Function* function_;
// Index in list of results.
int index_;
// Where the result variable is defined.
Location location_;
// Backend representation.
Bvariable* backend_;
// Whether something takes the address of this variable.
bool is_address_taken_;
// Whether something takes the address of this variable such that
// the address does not escape the function.
bool is_non_escaping_address_taken_;
// Whether this variable escapes the function it is created in. This is
// true until shown otherwise.
bool escapes_;
};
// The value we keep for a named constant. This lets us hold a type
// and an expression.
class Named_constant
{
public:
Named_constant(Type* type, Expression* expr, int iota_value,
Location location)
: type_(type), expr_(expr), iota_value_(iota_value), location_(location),
lowering_(false), is_sink_(false), bconst_(NULL)
{ }
Type*
type() const
{ return this->type_; }
void
set_type(Type* t);
Expression*
expr() const
{ return this->expr_; }
int
iota_value() const
{ return this->iota_value_; }
Location
location() const
{ return this->location_; }
// Whether we are lowering.
bool
lowering() const
{ return this->lowering_; }
// Set that we are lowering.
void
set_lowering()
{ this->lowering_ = true; }
// We are no longer lowering.
void
clear_lowering()
{ this->lowering_ = false; }
bool
is_sink() const
{ return this->is_sink_; }
void
set_is_sink()
{ this->is_sink_ = true; }
// Traverse the expression.
int
traverse_expression(Traverse*);
// Determine the type of the constant if necessary.
void
determine_type();
// Indicate that we found and reported an error for this constant.
void
set_error();
// Export the constant.
void
export_const(Export*, const std::string& name) const;
// Import a constant.
static void
import_const(Import*, std::string*, Type**, Expression**);
// Get the backend representation of the constant value.
Bexpression*
get_backend(Gogo*, Named_object*);
private:
// The type of the constant.
Type* type_;
// The expression for the constant.
Expression* expr_;
// If the predeclared constant iota is used in EXPR_, this is the
// value it will have. We do this because at parse time we don't
// know whether the name "iota" will refer to the predeclared
// constant or to something else. We put in the right value in when
// we lower.
int iota_value_;
// The location of the definition.
Location location_;
// Whether we are currently lowering this constant.
bool lowering_;
// Whether this constant is blank named and needs only type checking.
bool is_sink_;
// The backend representation of the constant value.
Bexpression* bconst_;
};
// A type declaration.
class Type_declaration
{
public:
Type_declaration(Location location)
: location_(location), in_function_(NULL), in_function_index_(0),
methods_(), issued_warning_(false)
{ }
// Return the location.
Location
location() const
{ return this->location_; }
// Return the function in which this type is declared. This will
// return NULL for a type declared in global scope.
Named_object*
in_function(unsigned int* pindex)
{
*pindex = this->in_function_index_;
return this->in_function_;
}
// Set the function in which this type is declared.
void
set_in_function(Named_object* f, unsigned int index)
{
this->in_function_ = f;
this->in_function_index_ = index;
}
// Add a method to this type. This is used when methods are defined
// before the type.
Named_object*
add_method(const std::string& name, Function* function);
// Add a method declaration to this type.
Named_object*
add_method_declaration(const std::string& name, Package*,
Function_type* type, Location location);
// Add an already created object as a method.
void
add_existing_method(Named_object* no)
{ this->methods_.push_back(no); }
// Return whether any methods were defined.
bool
has_methods() const;
// Return the methods.
const std::vector<Named_object*>*
methods() const
{ return &this->methods_; }
// Define methods when the real type is known.
void
define_methods(Named_type*);
// This is called if we are trying to use this type. It returns
// true if we should issue a warning.
bool
using_type();
private:
// The location of the type declaration.
Location location_;
// If this type is declared in a function, a pointer back to the
// function in which it is defined.
Named_object* in_function_;
// The index of this type in IN_FUNCTION_.
unsigned int in_function_index_;
// Methods defined before the type is defined.
std::vector<Named_object*> methods_;
// True if we have issued a warning about a use of this type
// declaration when it is undefined.
bool issued_warning_;
};
// An unknown object. These are created by the parser for forward
// references to names which have not been seen before. In a correct
// program, these will always point to a real definition by the end of
// the parse. Because they point to another Named_object, these may
// only be referenced by Unknown_expression objects.
class Unknown_name
{
public:
Unknown_name(Location location)
: location_(location), real_named_object_(NULL)
{ }
// Return the location where this name was first seen.
Location
location() const
{ return this->location_; }
// Return the real named object that this points to, or NULL if it
// was never resolved.
Named_object*
real_named_object() const
{ return this->real_named_object_; }
// Set the real named object that this points to.
void
set_real_named_object(Named_object* no);
private:
// The location where this name was first seen.
Location location_;
// The real named object when it is known.
Named_object*
real_named_object_;
};
// A named object named. This is the result of a declaration. We
// don't use a superclass because they all have to be handled
// differently.
class Named_object
{
public:
enum Classification
{
// An uninitialized Named_object. We should never see this.
NAMED_OBJECT_UNINITIALIZED,
// An erroneous name. This indicates a parse error, to avoid
// later errors about undefined references.
NAMED_OBJECT_ERRONEOUS,
// An unknown name. This is used for forward references. In a
// correct program, these will all be resolved by the end of the
// parse.
NAMED_OBJECT_UNKNOWN,
// A const.
NAMED_OBJECT_CONST,
// A type.
NAMED_OBJECT_TYPE,
// A forward type declaration.
NAMED_OBJECT_TYPE_DECLARATION,
// A var.
NAMED_OBJECT_VAR,
// A result variable in a function.
NAMED_OBJECT_RESULT_VAR,
// The blank identifier--the special variable named _.
NAMED_OBJECT_SINK,
// A func.
NAMED_OBJECT_FUNC,
// A forward func declaration.
NAMED_OBJECT_FUNC_DECLARATION,
// A package.
NAMED_OBJECT_PACKAGE
};
// Return the classification.
Classification
classification() const
{ return this->classification_; }
// Classifiers.
bool
is_erroneous() const
{ return this->classification_ == NAMED_OBJECT_ERRONEOUS; }
bool
is_unknown() const
{ return this->classification_ == NAMED_OBJECT_UNKNOWN; }
bool
is_const() const
{ return this->classification_ == NAMED_OBJECT_CONST; }
bool
is_type() const
{ return this->classification_ == NAMED_OBJECT_TYPE; }
bool
is_type_declaration() const
{ return this->classification_ == NAMED_OBJECT_TYPE_DECLARATION; }
bool
is_variable() const
{ return this->classification_ == NAMED_OBJECT_VAR; }
bool
is_result_variable() const
{ return this->classification_ == NAMED_OBJECT_RESULT_VAR; }
bool
is_sink() const
{ return this->classification_ == NAMED_OBJECT_SINK; }
bool
is_function() const
{ return this->classification_ == NAMED_OBJECT_FUNC; }
bool
is_function_declaration() const
{ return this->classification_ == NAMED_OBJECT_FUNC_DECLARATION; }
bool
is_package() const
{ return this->classification_ == NAMED_OBJECT_PACKAGE; }
// Creators.
static Named_object*
make_erroneous_name(const std::string& name)
{ return new Named_object(name, NULL, NAMED_OBJECT_ERRONEOUS); }
static Named_object*
make_unknown_name(const std::string& name, Location);
static Named_object*
make_constant(const Typed_identifier&, const Package*, Expression*,
int iota_value);
static Named_object*
make_type(const std::string&, const Package*, Type*, Location);
static Named_object*
make_type_declaration(const std::string&, const Package*, Location);
static Named_object*
make_variable(const std::string&, const Package*, Variable*);
static Named_object*
make_result_variable(const std::string&, Result_variable*);
static Named_object*
make_sink();
static Named_object*
make_function(const std::string&, const Package*, Function*);
static Named_object*
make_function_declaration(const std::string&, const Package*, Function_type*,
Location);
static Named_object*
make_package(const std::string& alias, Package* package);
// Getters.
Unknown_name*
unknown_value()
{
go_assert(this->classification_ == NAMED_OBJECT_UNKNOWN);
return this->u_.unknown_value;
}
const Unknown_name*
unknown_value() const
{
go_assert(this->classification_ == NAMED_OBJECT_UNKNOWN);
return this->u_.unknown_value;
}
Named_constant*
const_value()
{
go_assert(this->classification_ == NAMED_OBJECT_CONST);
return this->u_.const_value;
}
const Named_constant*
const_value() const
{
go_assert(this->classification_ == NAMED_OBJECT_CONST);
return this->u_.const_value;
}
Named_type*
type_value()
{
go_assert(this->classification_ == NAMED_OBJECT_TYPE);
return this->u_.type_value;
}
const Named_type*
type_value() const
{
go_assert(this->classification_ == NAMED_OBJECT_TYPE);
return this->u_.type_value;
}
Type_declaration*
type_declaration_value()
{
go_assert(this->classification_ == NAMED_OBJECT_TYPE_DECLARATION);
return this->u_.type_declaration;
}
const Type_declaration*
type_declaration_value() const
{
go_assert(this->classification_ == NAMED_OBJECT_TYPE_DECLARATION);
return this->u_.type_declaration;
}
Variable*
var_value()
{
go_assert(this->classification_ == NAMED_OBJECT_VAR);
return this->u_.var_value;
}
const Variable*
var_value() const
{
go_assert(this->classification_ == NAMED_OBJECT_VAR);
return this->u_.var_value;
}
Result_variable*
result_var_value()
{
go_assert(this->classification_ == NAMED_OBJECT_RESULT_VAR);
return this->u_.result_var_value;
}
const Result_variable*
result_var_value() const
{
go_assert(this->classification_ == NAMED_OBJECT_RESULT_VAR);
return this->u_.result_var_value;
}
Function*
func_value()
{
go_assert(this->classification_ == NAMED_OBJECT_FUNC);
return this->u_.func_value;
}
const Function*
func_value() const
{
go_assert(this->classification_ == NAMED_OBJECT_FUNC);
return this->u_.func_value;
}
Function_declaration*
func_declaration_value()
{
go_assert(this->classification_ == NAMED_OBJECT_FUNC_DECLARATION);
return this->u_.func_declaration_value;
}
const Function_declaration*
func_declaration_value() const
{
go_assert(this->classification_ == NAMED_OBJECT_FUNC_DECLARATION);
return this->u_.func_declaration_value;
}
Package*
package_value()
{
go_assert(this->classification_ == NAMED_OBJECT_PACKAGE);
return this->u_.package_value;
}
const Package*
package_value() const
{
go_assert(this->classification_ == NAMED_OBJECT_PACKAGE);
return this->u_.package_value;
}
const std::string&
name() const
{ return this->name_; }
// Return the name to use in an error message. The difference is
// that if this Named_object is defined in a different package, this
// will return PACKAGE.NAME.
std::string
message_name() const;
const Package*
package() const
{ return this->package_; }
// Resolve an unknown value if possible. This returns the same
// Named_object or a new one.
Named_object*
resolve()
{
Named_object* ret = this;
if (this->is_unknown())
{
Named_object* r = this->unknown_value()->real_named_object();
if (r != NULL)
ret = r;
}
return ret;
}
const Named_object*
resolve() const
{
const Named_object* ret = this;
if (this->is_unknown())
{
const Named_object* r = this->unknown_value()->real_named_object();
if (r != NULL)
ret = r;
}
return ret;
}
// The location where this object was defined or referenced.
Location
location() const;
// Convert a variable to the backend representation.
Bvariable*
get_backend_variable(Gogo*, Named_object* function);
// Return the external identifier for this object.
std::string
get_id(Gogo*);
// Get the backend representation of this object.
void
get_backend(Gogo*, std::vector<Bexpression*>&, std::vector<Btype*>&,
std::vector<Bfunction*>&);
// Define a type declaration.
void
set_type_value(Named_type*);
// Define a function declaration.
void
set_function_value(Function*);
// Declare an unknown name as a type declaration.
void
declare_as_type();
// Export this object.
void
export_named_object(Export*) const;
// Mark this named object as an invalid redefinition of another object.
void
set_is_redefinition()
{ this->is_redefinition_ = true; }
// Return whether or not this object is a invalid redefinition of another
// object.
bool
is_redefinition() const
{ return this->is_redefinition_; }
private:
Named_object(const std::string&, const Package*, Classification);
// The name of the object.
std::string name_;
// The package that this object is in. This is NULL if it is in the
// file we are compiling.
const Package* package_;
// The type of object this is.
Classification classification_;
// The real data.
union
{
Unknown_name* unknown_value;
Named_constant* const_value;
Named_type* type_value;
Type_declaration* type_declaration;
Variable* var_value;
Result_variable* result_var_value;
Function* func_value;
Function_declaration* func_declaration_value;
Package* package_value;
} u_;
// True if this object is an invalid redefinition of another object.
bool is_redefinition_;
};
// A binding contour. This binds names to objects.
class Bindings
{
public:
// Type for mapping from names to objects.
typedef Unordered_map(std::string, Named_object*) Contour;
Bindings(Bindings* enclosing);
// Add an erroneous name.
Named_object*
add_erroneous_name(const std::string& name)
{ return this->add_named_object(Named_object::make_erroneous_name(name)); }
// Add an unknown name.
Named_object*
add_unknown_name(const std::string& name, Location location)
{
return this->add_named_object(Named_object::make_unknown_name(name,
location));
}
// Add a constant.
Named_object*
add_constant(const Typed_identifier& tid, const Package* package,
Expression* expr, int iota_value)
{
return this->add_named_object(Named_object::make_constant(tid, package,
expr,
iota_value));
}
// Add a type.
Named_object*
add_type(const std::string& name, const Package* package, Type* type,
Location location)
{
return this->add_named_object(Named_object::make_type(name, package, type,
location));
}
// Add a named type. This is used for builtin types, and to add an
// imported type to the global scope.
Named_object*
add_named_type(Named_type* named_type);
// Add a type declaration.
Named_object*
add_type_declaration(const std::string& name, const Package* package,
Location location)
{
Named_object* no = Named_object::make_type_declaration(name, package,
location);
return this->add_named_object(no);
}
// Add a variable.
Named_object*
add_variable(const std::string& name, const Package* package,
Variable* variable)
{
return this->add_named_object(Named_object::make_variable(name, package,
variable));
}
// Add a result variable.
Named_object*
add_result_variable(const std::string& name, Result_variable* result)
{
return this->add_named_object(Named_object::make_result_variable(name,
result));
}
// Add a function.
Named_object*
add_function(const std::string& name, const Package*, Function* function);
// Add a function declaration.
Named_object*
add_function_declaration(const std::string& name, const Package* package,
Function_type* type, Location location);
// Add a package. The location is the location of the import
// statement.
Named_object*
add_package(const std::string& alias, Package* package)
{
Named_object* no = Named_object::make_package(alias, package);
return this->add_named_object(no);
}
// Define a type which was already declared.
void
define_type(Named_object*, Named_type*);
// Add a method to the list of objects. This is not added to the
// lookup table.
void
add_method(Named_object*);
// Add a named object to this binding.
Named_object*
add_named_object(Named_object* no)
{ return this->add_named_object_to_contour(&this->bindings_, no); }
// Clear all names in file scope from the bindings.
void
clear_file_scope(Gogo*);
// Look up a name in this binding contour and in any enclosing
// binding contours. This returns NULL if the name is not found.
Named_object*
lookup(const std::string&) const;
// Look up a name in this binding contour without looking in any
// enclosing binding contours. Returns NULL if the name is not found.
Named_object*
lookup_local(const std::string&) const;
// Remove a name.
void
remove_binding(Named_object*);
// Mark all variables as used. This is used for some types of parse
// error.
void
mark_locals_used();
// Traverse the tree. See the Traverse class.
int
traverse(Traverse*, bool is_global);
// Iterate over definitions. This does not include things which
// were only declared.
typedef std::vector<Named_object*>::const_iterator
const_definitions_iterator;
const_definitions_iterator
begin_definitions() const
{ return this->named_objects_.begin(); }
const_definitions_iterator
end_definitions() const
{ return this->named_objects_.end(); }
// Return the number of definitions.
size_t
size_definitions() const
{ return this->named_objects_.size(); }
// Return whether there are no definitions.
bool
empty_definitions() const
{ return this->named_objects_.empty(); }
// Iterate over declarations. This is everything that has been
// declared, which includes everything which has been defined.
typedef Contour::const_iterator const_declarations_iterator;
const_declarations_iterator
begin_declarations() const
{ return this->bindings_.begin(); }
const_declarations_iterator
end_declarations() const
{ return this->bindings_.end(); }
// Return the number of declarations.
size_t
size_declarations() const
{ return this->bindings_.size(); }
// Return whether there are no declarations.
bool
empty_declarations() const
{ return this->bindings_.empty(); }
// Return the first declaration.
Named_object*
first_declaration()
{ return this->bindings_.empty() ? NULL : this->bindings_.begin()->second; }
private:
Named_object*
add_named_object_to_contour(Contour*, Named_object*);
Named_object*
new_definition(Named_object*, Named_object*);
// Enclosing bindings.
Bindings* enclosing_;
// The list of objects.
std::vector<Named_object*> named_objects_;
// The mapping from names to objects.
Contour bindings_;
};
// A label.
class Label
{
public:
Label(const std::string& name)
: name_(name), location_(Linemap::unknown_location()), snapshot_(NULL),
refs_(), is_used_(false), blabel_(NULL), depth_(DEPTH_UNKNOWN)
{ }
// Return the label's name.
const std::string&
name() const
{ return this->name_; }
// Return whether the label has been defined.
bool
is_defined() const
{ return