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/*
* Symbol scoping.
*
* This is pretty trivial.
*
* Copyright (C) 2003 Transmeta Corp.
* 2003-2004 Linus Torvalds
*
* Licensed under the Open Software License version 1.1
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "lib.h"
#include "allocate.h"
#include "symbol.h"
#include "scope.h"
static struct scope builtin_scope = { .next = &builtin_scope };
struct scope *block_scope = &builtin_scope, // regular automatic variables etc
*function_scope = &builtin_scope, // labels, arguments etc
*file_scope = &builtin_scope, // static
*global_scope = &builtin_scope; // externally visible
void bind_scope(struct symbol *sym, struct scope *scope)
{
sym->scope = scope;
add_symbol(&scope->symbols, sym);
}
static void start_scope(struct scope **s)
{
struct scope *scope = __alloc_scope(0);
memset(scope, 0, sizeof(*scope));
scope->next = *s;
*s = scope;
}
void start_file_scope(void)
{
struct scope *scope = __alloc_scope(0);
memset(scope, 0, sizeof(*scope));
scope->next = &builtin_scope;
file_scope = scope;
/* top-level stuff defaults to file scope, "extern" etc will choose global scope */
function_scope = scope;
block_scope = scope;
}
void start_symbol_scope(void)
{
start_scope(&block_scope);
}
void start_function_scope(void)
{
start_scope(&function_scope);
start_scope(&block_scope);
}
static void remove_symbol_scope(struct symbol *sym)
{
struct symbol **ptr = sym->id_list;
while (*ptr != sym)
ptr = &(*ptr)->next_id;
*ptr = sym->next_id;
}
static void end_scope(struct scope **s)
{
struct scope *scope = *s;
struct symbol_list *symbols = scope->symbols;
struct symbol *sym;
*s = scope->next;
scope->symbols = NULL;
FOR_EACH_PTR(symbols, sym) {
remove_symbol_scope(sym);
} END_FOR_EACH_PTR(sym);
}
void end_file_scope(void)
{
end_scope(&file_scope);
}
void new_file_scope(void)
{
if (file_scope != &builtin_scope)
end_file_scope();
start_file_scope();
}
void end_symbol_scope(void)
{
end_scope(&block_scope);
}
void end_function_scope(void)
{
end_scope(&block_scope);
end_scope(&function_scope);
}
int is_outer_scope(struct scope *scope)
{
if (scope == block_scope)
return 0;
if (scope == &builtin_scope && block_scope->next == &builtin_scope)
return 0;
return 1;
}
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