scope.c

   1 /*
   2  * Symbol scoping.
   3  *
   4  * This is pretty trivial.
   5  *
   6  * Copyright (C) 2003 Transmeta Corp, all rights reserved.
   7  */
   8 #include <stdlib.h>
   9 #include <string.h>
  10
  11 #include "lib.h"
  12 #include "symbol.h"
  13 #include "scope.h"
  14
  15 static struct scope toplevel_scope = { .next = &toplevel_scope };
  16
  17 struct scope    *block_scope = &toplevel_scope,
  18                 *function_scope = &toplevel_scope,
  19                 *file_scope = &toplevel_scope;
  20
  21 void bind_scope(struct symbol *sym, struct scope *scope)
  22 {
  23         add_symbol(&scope->symbols, sym);
  24 }
  25
  26 static void start_scope(struct scope **s)
  27 {
  28         struct scope *scope = __alloc_bytes(sizeof(*scope));
  29         memset(scope, 0, sizeof(*scope));
  30         scope->next = *s;
  31         *s = scope;
  32 }
  33
  34 void start_symbol_scope(void)
  35 {
  36         start_scope(&block_scope);
  37 }
  38
  39 void start_function_scope(void)
  40 {
  41         start_scope(&function_scope);
  42         start_scope(&block_scope);
  43 }
  44
  45 static void remove_symbol_scope(struct symbol *sym, void *data, int flags)
  46 {
  47         struct symbol **ptr = sym->id_list;
  48
  49         while (*ptr != sym)
  50                 ptr = &(*ptr)->next_id;
  51         *ptr = sym->next_id;
  52 }
  53
  54 static void end_scope(struct scope **s)
  55 {
  56         struct scope *scope = *s;
  57         struct symbol_list *symbols = scope->symbols;
  58
  59         *s = scope->next;
  60         scope->symbols = NULL;
  61         symbol_iterate(symbols, remove_symbol_scope, NULL);
  62 }
  63
  64 void end_symbol_scope(void)
  65 {
  66         end_scope(&block_scope);
  67 }
  68
  69 void end_function_scope(void)
  70 {
  71         end_scope(&block_scope);
  72         end_scope(&function_scope);
  73 }