expression.h

   1 #ifndef EXPRESSION_H
   2 #define EXPRESSION_H
   3 /*
   4  * sparse/expression.h
   5  *
   6  * Copyright (C) 2003 Transmeta Corp.
   7  *               2003 Linus Torvalds
   8  *
   9  *  Licensed under the Open Software License version 1.1
  10  *
  11  * Declarations and helper functions for expression parsing.
  12  */
  13
  14 struct expression_list;
  15
  16 enum expression_type {
  17         EXPR_VALUE,
  18         EXPR_STRING,
  19         EXPR_SYMBOL,
  20         EXPR_BINOP,
  21         EXPR_ASSIGNMENT,
  22         EXPR_LOGICAL,
  23         EXPR_DEREF,
  24         EXPR_PREOP,
  25         EXPR_POSTOP,
  26         EXPR_CAST,
  27         EXPR_SIZEOF,
  28         EXPR_CONDITIONAL,
  29         EXPR_STATEMENT,
  30         EXPR_CALL,
  31         EXPR_COMMA,
  32         EXPR_COMPARE,
  33         EXPR_BITFIELD,
  34         EXPR_LABEL,
  35         EXPR_INITIALIZER,       // initializer list
  36         EXPR_IDENTIFIER,        // identifier in initializer
  37         EXPR_INDEX,             // index in initializer
  38         EXPR_POS,               // position in initializer
  39 };
  40
  41 struct expression {
  42         enum expression_type type;
  43         int op;
  44         struct position pos;
  45         struct symbol *ctype;
  46         union {
  47                 // EXPR_VALUE
  48                 unsigned long long value;
  49
  50                 // EXPR_STRING
  51                 struct string *string;
  52
  53                 // EXPR_UNOP, EXPR_PREOP and EXPR_POSTOP
  54                 struct expression *unop;
  55
  56                 // EXPR_SYMBOL
  57                 struct /* symbol_arg */ {
  58                         struct symbol *symbol;
  59                         struct ident *symbol_name;
  60                 };
  61
  62                 // EXPR_STATEMENT
  63                 struct statement *statement;
  64
  65                 // EXPR_BINOP, EXPR_COMMA, EXPR_COMPARE, EXPR_LOGICAL and EXPR_ASSIGNMENT
  66                 struct /* binop_arg */ {
  67                         struct expression *left, *right;
  68                 };
  69                 // EXPR_DEREF
  70                 struct /* deref_arg */ {
  71                         struct expression *deref;
  72                         struct ident *member;
  73                 };
  74                 // EXPR_CAST and EXPR_SIZEOF
  75                 struct /* cast_arg */ {
  76                         struct symbol *cast_type;
  77                         struct expression *cast_expression;
  78                 };
  79                 // EXPR_CONDITIONAL
  80                 struct /* conditional_expr */ {
  81                         struct expression *conditional, *cond_true, *cond_false;
  82                 };
  83                 // EXPR_CALL
  84                 struct /* call_expr */ {
  85                         struct expression *fn;
  86                         struct expression_list *args;
  87                 };
  88                 // EXPR_BITFIELD
  89                 struct /* bitfield_expr */ {
  90                         unsigned char bitpos, nrbits;
  91                         struct expression *address;
  92                 };
  93                 // EXPR_LABEL
  94                 struct /* label_expr */ {
  95                         struct symbol *label_symbol;
  96                 };
  97                 // EXPR_INITIALIZER
  98                 struct expression_list *expr_list;
  99                 // EXPR_IDENTIFIER
 100                 struct ident *expr_ident;
 101                 // EXPR_INDEX
 102                 struct /* index_expr */ {
 103                         unsigned int idx_from, idx_to;
 104                 };
 105                 // EXPR_POS
 106                 struct /* initpos_expr */ {
 107                         unsigned int init_offset;
 108                         struct symbol *init_sym;
 109                         struct expression *init_expr;
 110                 };
 111         };
 112 };
 113
 114 /* Constant expression values */
 115 long long get_expression_value(struct expression *);
 116
 117 /* Expression parsing */
 118 struct token *parse_expression(struct token *token, struct expression **tree);
 119 struct token *conditional_expression(struct token *token, struct expression **tree);
 120 struct token *primary_expression(struct token *token, struct expression **tree);
 121 struct token *parens_expression(struct token *token, struct expression **expr, const char *where);
 122 struct token *assignment_expression(struct token *token, struct expression **tree);
 123
 124 extern void check_duplicates(struct symbol *sym);
 125 extern struct symbol *evaluate_symbol(struct symbol *sym);
 126 extern struct symbol *evaluate_statement(struct statement *stmt);
 127 extern struct symbol *evaluate_expression(struct expression *);
 128
 129 extern void expand_symbol(struct symbol *);
 130
 131 static inline struct expression *alloc_expression(struct position pos, int type)
 132 {
 133         struct expression *expr = __alloc_expression(0);
 134         expr->type = type;
 135         expr->pos = pos;
 136         return expr;
 137 }
 138
 139 static inline struct expression *alloc_const_expression(struct position pos, int value)
 140 {
 141         struct expression *expr = __alloc_expression(0);
 142         expr->type = EXPR_VALUE;
 143         expr->pos = pos;
 144         expr->value = value;
 145         expr->ctype = &int_ctype;
 146         return expr;
 147 }
 148
 149 /* Type name parsing */
 150 struct token *typename(struct token *, struct symbol **);
 151
 152 static inline int lookup_type(struct token *token)
 153 {
 154         if (token->pos.type == TOKEN_IDENT)
 155                 return lookup_symbol(token->ident, NS_TYPEDEF) != NULL;
 156         return 0;
 157 }
 158
 159 /* Statement parsing */
 160 struct statement *alloc_statement(struct position pos, int type);
 161 struct token *initializer(struct expression **tree, struct token *token);
 162 struct token *compound_statement(struct token *, struct statement *);
 163
 164 /* The preprocessor calls this 'constant_expression()' */
 165 #define constant_expression(token,tree) conditional_expression(token, tree)
 166
 167 /* Cast folding of constant values.. */
 168 void cast_value(struct expression *expr, struct symbol *newtype,
 169         struct expression *old, struct symbol *oldtype);
 170
 171 #endif