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_LOGICAL,
  20         EXPR_DEREF,
  21         EXPR_PREOP,
  22         EXPR_POSTOP,
  23         EXPR_CAST,
  24         EXPR_SIZEOF,
  25         EXPR_CONDITIONAL,
  26         EXPR_STATEMENT,
  27         EXPR_CALL,
  28         EXPR_COMMA,
  29         EXPR_COMPARE,
  30         EXPR_BITFIELD,
  31         EXPR_INITIALIZER,       // initializer list
  32         EXPR_IDENTIFIER,        // identifier in initializer
  33         EXPR_INDEX,             // index in initializer
  34 };
  35
  36 struct expression {
  37         enum expression_type type;
  38         int op;
  39         struct position pos;
  40         struct symbol *ctype;
  41         union {
  42                 // EXPR_VALUE
  43                 unsigned long long value;
  44
  45                 // EXPR_STRING
  46                 struct string *string;
  47
  48                 // EXPR_UNOP, EXPR_PREOP and EXPR_POSTOP
  49                 struct expression *unop;
  50
  51                 // EXPR_SYMBOL
  52                 struct symbol_arg {
  53                         struct symbol *symbol;
  54                         struct ident *symbol_name;
  55                 };
  56
  57                 // EXPR_STATEMENT
  58                 struct statement *statement;
  59
  60                 // EXPR_BINOP, EXPR_COMMA, EXPR_COMPARE, EXPR_LOGICAL and EXPR_ASSIGNMENT
  61                 struct binop_arg {
  62                         struct expression *left, *right;
  63                 };
  64                 // EXPR_DEREF
  65                 struct deref_arg {
  66                         struct expression *deref;
  67                         struct ident *member;
  68                 };
  69                 // EXPR_CAST and EXPR_SIZEOF
  70                 struct cast_arg {
  71                         struct symbol *cast_type;
  72                         struct expression *cast_expression;
  73                 };
  74                 // EXPR_CONDITIONAL
  75                 struct conditional_expr {
  76                         struct expression *conditional, *cond_true, *cond_false;
  77                 };
  78                 // EXPR_CALL
  79                 struct call_expr {
  80                         struct expression *fn;
  81                         struct expression_list *args;
  82                 };
  83                 // EXPR_BITFIELD
  84                 struct bitfield_expr {
  85                         unsigned char bitpos, nrbits;
  86                         struct expression *address;
  87                 };
  88                 // EXPR_INITIALIZER
  89                 struct expression_list *expr_list;
  90                 // EXPR_IDENTIFIER
  91                 struct ident *expr_ident;
  92                 // EXPR_INDEX
  93                 struct index_expr {
  94                         unsigned int idx_from, idx_to;
  95                 };
  96         };
  97 };
  98
  99 /* Constant expression values */
 100 long long get_expression_value(struct expression *);
 101
 102 /* Expression parsing */
 103 struct token *parse_expression(struct token *token, struct expression **tree);
 104 struct token *conditional_expression(struct token *token, struct expression **tree);
 105 struct token *primary_expression(struct token *token, struct expression **tree);
 106 struct token *parens_expression(struct token *token, struct expression **expr, const char *where);
 107 struct token *assignment_expression(struct token *token, struct expression **tree);
 108
 109 extern struct symbol *evaluate_symbol(struct symbol *sym);
 110 extern struct symbol *evaluate_statement(struct statement *stmt);
 111 extern struct symbol *evaluate_expression(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 /* The preprocessor calls this 'constant_expression()' */
 137 #define constant_expression(token,tree) conditional_expression(token, tree)
 138
 139 #endif