expression.h

   1 #ifndef EXPRESSION_H
   2 #define EXPRESSION_H
   3 /*
   4  * sparse/expression.h
   5  *
   6  * Copyright (C) 2003 Transmeta Corp, all rights reserved.
   7  *
   8  * Declarations and helper functions for expression parsing.
   9  */
  10
  11 struct expression_list;
  12
  13 enum expression_type {
  14         EXPR_VALUE,
  15         EXPR_STRING,
  16         EXPR_SYMBOL,
  17         EXPR_BINOP,
  18         EXPR_ASSIGNMENT,
  19         EXPR_DEREF,
  20         EXPR_PREOP,
  21         EXPR_POSTOP,
  22         EXPR_CAST,
  23         EXPR_SIZEOF,
  24         EXPR_CONDITIONAL,
  25         EXPR_STATEMENT,
  26         EXPR_CALL,
  27         EXPR_COMMA,
  28         EXPR_COMPARE,
  29         EXPR_BITFIELD,
  30         EXPR_INITIALIZER,       // initializer list
  31         EXPR_IDENTIFIER,        // identifier in initializer
  32         EXPR_INDEX,             // index in initializer
  33 };
  34
  35 struct expression {
  36         enum expression_type type;
  37         int op;
  38         struct position pos;
  39         struct symbol *ctype;
  40         union {
  41                 // EXPR_VALUE
  42                 unsigned long long value;
  43
  44                 // EXPR_STRING
  45                 struct string *string;
  46
  47                 // EXPR_UNOP, EXPR_PREOP and EXPR_POSTOP
  48                 struct expression *unop;
  49
  50                 // EXPR_SYMBOL
  51                 struct symbol_arg {
  52                         struct symbol *symbol;
  53                         struct ident *symbol_name;
  54                 };
  55
  56                 // EXPR_STATEMENT
  57                 struct statement *statement;
  58
  59                 // EXPR_BINOP, EXPR_COMMA, EXPR_COMPARE and EXPR_ASSIGNMENT
  60                 struct binop_arg {
  61                         struct expression *left, *right;
  62                 };
  63                 // EXPR_DEREF
  64                 struct deref_arg {
  65                         struct expression *deref;
  66                         struct ident *member;
  67                 };
  68                 // EXPR_CAST and EXPR_SIZEOF
  69                 struct cast_arg {
  70                         struct symbol *cast_type;
  71                         struct expression *cast_expression;
  72                 };
  73                 // EXPR_CONDITIONAL
  74                 struct conditional_expr {
  75                         struct expression *conditional, *cond_true, *cond_false;
  76                 };
  77                 // EXPR_CALL
  78                 struct call_expr {
  79                         struct expression *fn;
  80                         struct expression_list *args;
  81                 };
  82                 // EXPR_BITFIELD
  83                 struct bitfield_expr {
  84                         unsigned char bitpos, nrbits;
  85                         struct expression *address;
  86                 };
  87                 // EXPR_INITIALIZER
  88                 struct expression_list *expr_list;
  89                 // EXPR_IDENTIFIER
  90                 struct ident *expr_ident;
  91                 // EXPR_INDEX
  92                 struct index_expr {
  93                         unsigned int idx_from, idx_to;
  94                 };
  95         };
  96 };
  97
  98 /* Constant expression values */
  99 long long get_expression_value(struct expression *);
 100
 101 /* Expression parsing */
 102 struct token *parse_expression(struct token *token, struct expression **tree);
 103 struct token *conditional_expression(struct token *token, struct expression **tree);
 104 struct token *primary_expression(struct token *token, struct expression **tree);
 105 struct token *parens_expression(struct token *token, struct expression **expr, const char *where);
 106 struct token *assignment_expression(struct token *token, struct expression **tree);
 107
 108 extern struct symbol *evaluate_symbol(struct symbol *sym);
 109 extern struct symbol *evaluate_statement(struct statement *stmt);
 110 extern struct symbol *evaluate_expression(struct expression *);
 111 extern struct symbol *evaluate_initializer(struct symbol *, struct expression *);
 112
 113 static inline struct expression *alloc_expression(struct position pos, int type)
 114 {
 115         struct expression *expr = __alloc_expression(0);
 116         expr->type = type;
 117         expr->pos = pos;
 118         return expr;
 119 }
 120
 121 /* Type name parsing */
 122 struct token *typename(struct token *, struct symbol **);
 123
 124 static inline int lookup_type(struct token *token)
 125 {
 126         if (token->pos.type == TOKEN_IDENT)
 127                 return lookup_symbol(token->ident, NS_TYPEDEF) != NULL;
 128         return 0;
 129 }
 130
 131 /* Statement parsing */
 132 struct statement *alloc_statement(struct position pos, int type);
 133 struct token *initializer(struct expression **tree, struct token *token);
 134 struct token *compound_statement(struct token *, struct statement *);
 135
 136 extern void clean_up_statement(struct statement *stmt, void *_parent, int flags);
 137 extern void clean_up_symbol(struct symbol *sym, void *_parent, int flags);
 138
 139 /* The preprocessor calls this 'constant_expression()' */
 140 #define constant_expression(token,tree) conditional_expression(token, tree)
 141
 142 #endif