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_LABEL,
  34         EXPR_INITIALIZER,       // initializer list
  35         EXPR_IDENTIFIER,        // identifier in initializer
  36         EXPR_INDEX,             // index in initializer
  37         EXPR_POS,               // position in initializer
  38 };
  39
  40 struct expression {
  41         enum expression_type type;
  42         int op;
  43         struct position pos;
  44         struct symbol *ctype;
  45         union {
  46                 // EXPR_VALUE
  47                 unsigned long long value;
  48
  49                 // EXPR_STRING
  50                 struct string *string;
  51
  52                 // EXPR_UNOP, EXPR_PREOP and EXPR_POSTOP
  53                 struct expression *unop;
  54
  55                 // EXPR_SYMBOL
  56                 struct /* symbol_arg */ {
  57                         struct symbol *symbol;
  58                         struct ident *symbol_name;
  59                 };
  60
  61                 // EXPR_STATEMENT
  62                 struct statement *statement;
  63
  64                 // EXPR_BINOP, EXPR_COMMA, EXPR_COMPARE, EXPR_LOGICAL and EXPR_ASSIGNMENT
  65                 struct /* binop_arg */ {
  66                         struct expression *left, *right;
  67                 };
  68                 // EXPR_DEREF
  69                 struct /* deref_arg */ {
  70                         struct expression *deref;
  71                         struct ident *member;
  72                 };
  73                 // EXPR_CAST and EXPR_SIZEOF
  74                 struct /* cast_arg */ {
  75                         struct symbol *cast_type;
  76                         struct expression *cast_expression;
  77                 };
  78                 // EXPR_CONDITIONAL
  79                 struct /* conditional_expr */ {
  80                         struct expression *conditional, *cond_true, *cond_false;
  81                 };
  82                 // EXPR_CALL
  83                 struct /* call_expr */ {
  84                         struct expression *fn;
  85                         struct expression_list *args;
  86                 };
  87                 // EXPR_BITFIELD
  88                 struct /* bitfield_expr */ {
  89                         unsigned char bitpos, nrbits;
  90                         struct expression *address;
  91                 };
  92                 // EXPR_LABEL
  93                 struct /* label_expr */ {
  94                         struct symbol *label_symbol;
  95                 };
  96                 // EXPR_INITIALIZER
  97                 struct expression_list *expr_list;
  98                 // EXPR_IDENTIFIER
  99                 struct ident *expr_ident;
 100                 // EXPR_INDEX
 101                 struct /* index_expr */ {
 102                         unsigned int idx_from, idx_to;
 103                 };
 104                 // EXPR_POS
 105                 struct /* initpos_expr */ {
 106                         unsigned int init_offset;
 107                         struct symbol *init_sym;
 108                         struct expression *init_expr;
 109                 };
 110         };
 111 };
 112
 113 /* Constant expression values */
 114 long long get_expression_value(struct expression *);
 115
 116 /* Expression parsing */
 117 struct token *parse_expression(struct token *token, struct expression **tree);
 118 struct token *conditional_expression(struct token *token, struct expression **tree);
 119 struct token *primary_expression(struct token *token, struct expression **tree);
 120 struct token *parens_expression(struct token *token, struct expression **expr, const char *where);
 121 struct token *assignment_expression(struct token *token, struct expression **tree);
 122
 123 extern void check_duplicates(struct symbol *sym);
 124 extern struct symbol *evaluate_symbol(struct symbol *sym);
 125 extern struct symbol *evaluate_statement(struct statement *stmt);
 126 extern struct symbol *evaluate_expression(struct expression *);
 127
 128 static inline struct expression *alloc_expression(struct position pos, int type)
 129 {
 130         struct expression *expr = __alloc_expression(0);
 131         expr->type = type;
 132         expr->pos = pos;
 133         return expr;
 134 }
 135
 136 /* Type name parsing */
 137 struct token *typename(struct token *, struct symbol **);
 138
 139 static inline int lookup_type(struct token *token)
 140 {
 141         if (token->pos.type == TOKEN_IDENT)
 142                 return lookup_symbol(token->ident, NS_TYPEDEF) != NULL;
 143         return 0;
 144 }
 145
 146 /* Statement parsing */
 147 struct statement *alloc_statement(struct position pos, int type);
 148 struct token *initializer(struct expression **tree, struct token *token);
 149 struct token *compound_statement(struct token *, struct statement *);
 150
 151 /* The preprocessor calls this 'constant_expression()' */
 152 #define constant_expression(token,tree) conditional_expression(token, tree)
 153
 154 #endif