expression.h

   1 #ifndef EXPRESSION_H
   2 #define EXPRESSION_H
   3 /*
   4  * sparse/expression.h
   5  *
   6  * Copyright (C) 2003 Transmeta Corp.
   7  *
   8  *  Licensed under the Open Software License version 1.1
   9  *
  10  * Declarations and helper functions for expression parsing.
  11  */
  12
  13 struct expression_list;
  14
  15 enum expression_type {
  16         EXPR_VALUE,
  17         EXPR_STRING,
  18         EXPR_SYMBOL,
  19         EXPR_BINOP,
  20         EXPR_ASSIGNMENT,
  21         EXPR_LOGICAL,
  22         EXPR_DEREF,
  23         EXPR_PREOP,
  24         EXPR_POSTOP,
  25         EXPR_CAST,
  26         EXPR_SIZEOF,
  27         EXPR_CONDITIONAL,
  28         EXPR_STATEMENT,
  29         EXPR_CALL,
  30         EXPR_COMMA,
  31         EXPR_COMPARE,
  32         EXPR_BITFIELD,
  33         EXPR_INITIALIZER,       // initializer list
  34         EXPR_IDENTIFIER,        // identifier in initializer
  35         EXPR_INDEX,             // index in initializer
  36         EXPR_POS,               // position in initializer
  37 };
  38
  39 struct expression {
  40         enum expression_type type;
  41         int op;
  42         struct position pos;
  43         struct symbol *ctype;
  44         union {
  45                 // EXPR_VALUE
  46                 unsigned long long value;
  47
  48                 // EXPR_STRING
  49                 struct string *string;
  50
  51                 // EXPR_UNOP, EXPR_PREOP and EXPR_POSTOP
  52                 struct expression *unop;
  53
  54                 // EXPR_SYMBOL
  55                 struct symbol_arg {
  56                         struct symbol *symbol;
  57                         struct ident *symbol_name;
  58                 };
  59
  60                 // EXPR_STATEMENT
  61                 struct statement *statement;
  62
  63                 // EXPR_BINOP, EXPR_COMMA, EXPR_COMPARE, EXPR_LOGICAL and EXPR_ASSIGNMENT
  64                 struct binop_arg {
  65                         struct expression *left, *right;
  66                 };
  67                 // EXPR_DEREF
  68                 struct deref_arg {
  69                         struct expression *deref;
  70                         struct ident *member;
  71                 };
  72                 // EXPR_CAST and EXPR_SIZEOF
  73                 struct cast_arg {
  74                         struct symbol *cast_type;
  75                         struct expression *cast_expression;
  76                 };
  77                 // EXPR_CONDITIONAL
  78                 struct conditional_expr {
  79                         struct expression *conditional, *cond_true, *cond_false;
  80                 };
  81                 // EXPR_CALL
  82                 struct call_expr {
  83                         struct expression *fn;
  84                         struct expression_list *args;
  85                 };
  86                 // EXPR_BITFIELD
  87                 struct bitfield_expr {
  88                         unsigned char bitpos, nrbits;
  89                         struct expression *address;
  90                 };
  91                 // EXPR_INITIALIZER
  92                 struct expression_list *expr_list;
  93                 // EXPR_IDENTIFIER
  94                 struct ident *expr_ident;
  95                 // EXPR_INDEX
  96                 struct index_expr {
  97                         unsigned int idx_from, idx_to;
  98                 };
  99                 // EXPR_POS
 100                 struct initpos_expr {
 101                         unsigned int init_offset;
 102                         struct symbol *init_sym;
 103                         struct expression *init_expr;
 104                 };
 105         };
 106 };
 107
 108 /* Constant expression values */
 109 long long get_expression_value(struct expression *);
 110
 111 /* Expression parsing */
 112 struct token *parse_expression(struct token *token, struct expression **tree);
 113 struct token *conditional_expression(struct token *token, struct expression **tree);
 114 struct token *primary_expression(struct token *token, struct expression **tree);
 115 struct token *parens_expression(struct token *token, struct expression **expr, const char *where);
 116 struct token *assignment_expression(struct token *token, struct expression **tree);
 117
 118 extern void check_duplicates(struct symbol *sym);
 119 extern struct symbol *evaluate_symbol(struct symbol *sym);
 120 extern struct symbol *evaluate_statement(struct statement *stmt);
 121 extern struct symbol *evaluate_expression(struct expression *);
 122
 123 static inline struct expression *alloc_expression(struct position pos, int type)
 124 {
 125         struct expression *expr = __alloc_expression(0);
 126         expr->type = type;
 127         expr->pos = pos;
 128         return expr;
 129 }
 130
 131 /* Type name parsing */
 132 struct token *typename(struct token *, struct symbol **);
 133
 134 static inline int lookup_type(struct token *token)
 135 {
 136         if (token->pos.type == TOKEN_IDENT)
 137                 return lookup_symbol(token->ident, NS_TYPEDEF) != NULL;
 138         return 0;
 139 }
 140
 141 /* Statement parsing */
 142 struct statement *alloc_statement(struct position pos, int type);
 143 struct token *initializer(struct expression **tree, struct token *token);
 144 struct token *compound_statement(struct token *, struct statement *);
 145
 146 /* The preprocessor calls this 'constant_expression()' */
 147 #define constant_expression(token,tree) conditional_expression(token, tree)
 148
 149 #endif