[binutils.git] / gdb / expression.h

/* Definitions for expressions stored in reversed prefix form, for GDB.
   Copyright 1986, 1989, 1992, 1994, 2000 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#if !defined (EXPRESSION_H)
#define EXPRESSION_H 1


#include "symtab.h"		/* Needed for "struct block" type. */
#include "doublest.h"		/* Needed for DOUBLEST.  */


/* Definitions for saved C expressions.  */

/* An expression is represented as a vector of union exp_element's.
   Each exp_element is an opcode, except that some opcodes cause
   the following exp_element to be treated as a long or double constant
   or as a variable.  The opcodes are obeyed, using a stack for temporaries.
   The value is left on the temporary stack at the end.  */

/* When it is necessary to include a string,
   it can occupy as many exp_elements as it needs.
   We find the length of the string using strlen,
   divide to find out how many exp_elements are used up,
   and skip that many.  Strings, like numbers, are indicated
   by the preceding opcode.  */

enum exp_opcode
  {
    /* Used when it's necessary to pass an opcode which will be ignored,
       or to catch uninitialized values.  */
    OP_NULL,

/* BINOP_... operate on two values computed by following subexpressions,
   replacing them by one result value.  They take no immediate arguments.  */

    BINOP_ADD,			/* + */
    BINOP_SUB,			/* - */
    BINOP_MUL,			/* * */
    BINOP_DIV,			/* / */
    BINOP_REM,			/* % */
    BINOP_MOD,			/* mod (Knuth 1.2.4) */
    BINOP_LSH,			/* << */
    BINOP_RSH,			/* >> */
    BINOP_LOGICAL_AND,		/* && */
    BINOP_LOGICAL_OR,		/* || */
    BINOP_BITWISE_AND,		/* & */
    BINOP_BITWISE_IOR,		/* | */
    BINOP_BITWISE_XOR,		/* ^ */
    BINOP_EQUAL,		/* == */
    BINOP_NOTEQUAL,		/* != */
    BINOP_LESS,			/* < */
    BINOP_GTR,			/* > */
    BINOP_LEQ,			/* <= */
    BINOP_GEQ,			/* >= */
    BINOP_REPEAT,		/* @ */
    BINOP_ASSIGN,		/* = */
    BINOP_COMMA,		/* , */
    BINOP_SUBSCRIPT,		/* x[y] */
    BINOP_EXP,			/* Exponentiation */

    /* C++.  */

    BINOP_MIN,			/* <? */
    BINOP_MAX,			/* >? */

    /* STRUCTOP_MEMBER is used for pointer-to-member constructs.
       X . * Y translates into X STRUCTOP_MEMBER Y.  */
    STRUCTOP_MEMBER,

    /* STRUCTOP_MPTR is used for pointer-to-member constructs
       when X is a pointer instead of an aggregate.  */
    STRUCTOP_MPTR,

    /* end of C++.  */

    /* For Modula-2 integer division DIV */
    BINOP_INTDIV,

    BINOP_ASSIGN_MODIFY,	/* +=, -=, *=, and so on.
				   The following exp_element is another opcode,
				   a BINOP_, saying how to modify.
				   Then comes another BINOP_ASSIGN_MODIFY,
				   making three exp_elements in total.  */

    /* Modula-2 standard (binary) procedures */
    BINOP_VAL,
    BINOP_INCL,
    BINOP_EXCL,

    /* Concatenate two operands, such as character strings or bitstrings.
       If the first operand is a integer expression, then it means concatenate
       the second operand with itself that many times. */
    BINOP_CONCAT,

    /* For (OBSOLETE) Chill (OBSOLETE) and Pascal. */
    BINOP_IN,			/* Returns 1 iff ARG1 IN ARG2. */

    /* This is the "colon operator" used various places in (OBSOLETE)
       Chill (OBSOLETE). */
    BINOP_RANGE,

    /* This must be the highest BINOP_ value, for expprint.c.  */
    BINOP_END,

    /* Operates on three values computed by following subexpressions.  */
    TERNOP_COND,		/* ?: */

    /* A sub-string/sub-array.  (OBSOLETE) Chill (OBSOLETE) syntax:
       OP1(OP2:OP3).  Return elements OP2 through OP3 of OP1.  */
    TERNOP_SLICE,

    /* A sub-string/sub-array.  (OBSOLETE) Chill (OBSOLETE) syntax:
       OP1(OP2 UP OP3).  Return OP3 elements of OP1, starting with
       element OP2. */
    TERNOP_SLICE_COUNT,

    /* Multidimensional subscript operator, such as Modula-2 x[a,b,...].
       The dimensionality is encoded in the operator, like the number of
       function arguments in OP_FUNCALL, I.E. <OP><dimension><OP>.
       The value of the first following subexpression is subscripted
       by each of the next following subexpressions, one per dimension. */
    MULTI_SUBSCRIPT,

    /* The OP_... series take immediate following arguments.
       After the arguments come another OP_... (the same one)
       so that the grouping can be recognized from the end.  */

    /* OP_LONG is followed by a type pointer in the next exp_element
       and the long constant value in the following exp_element.
       Then comes another OP_LONG.
       Thus, the operation occupies four exp_elements.  */
    OP_LONG,

    /* OP_DOUBLE is similar but takes a DOUBLEST constant instead of a long.  */
    OP_DOUBLE,

    /* OP_VAR_VALUE takes one struct block * in the following element,
       and one struct symbol * in the following exp_element, followed by
       another OP_VAR_VALUE, making four exp_elements.  If the block is
       non-NULL, evaluate the symbol relative to the innermost frame
       executing in that block; if the block is NULL use the selected frame.  */
    OP_VAR_VALUE,

    /* OP_LAST is followed by an integer in the next exp_element.
       The integer is zero for the last value printed,
       or it is the absolute number of a history element.
       With another OP_LAST at the end, this makes three exp_elements.  */
    OP_LAST,

    /* OP_REGISTER is followed by an integer in the next exp_element.
       This is the number of a register to fetch (as an int).
       With another OP_REGISTER at the end, this makes three exp_elements.  */
    OP_REGISTER,

    /* OP_INTERNALVAR is followed by an internalvar ptr in the next exp_element.
       With another OP_INTERNALVAR at the end, this makes three exp_elements.  */
    OP_INTERNALVAR,

    /* OP_FUNCALL is followed by an integer in the next exp_element.
       The integer is the number of args to the function call.
       That many plus one values from following subexpressions
       are used, the first one being the function.
       The integer is followed by a repeat of OP_FUNCALL,
       making three exp_elements.  */
    OP_FUNCALL,

    /* This is EXACTLY like OP_FUNCALL but is semantically different.  
       In F77, array subscript expressions, substring expressions
       and function calls are  all exactly the same syntactically. They may 
       only be dismabiguated at runtime.  Thus this operator, which 
       indicates that we have found something of the form <name> ( <stuff> ) */
    OP_F77_UNDETERMINED_ARGLIST,

    /* The following OP is a special one, it introduces a F77 complex
       literal. It is followed by exactly two args that are doubles.  */
    OP_COMPLEX,

    /* OP_STRING represents a string constant.
       Its format is the same as that of a STRUCTOP, but the string
       data is just made into a string constant when the operation
       is executed.  */
    OP_STRING,

    /* OP_BITSTRING represents a packed bitstring constant.
       Its format is the same as that of a STRUCTOP, but the bitstring
       data is just made into a bitstring constant when the operation
       is executed.  */
    OP_BITSTRING,

    /* OP_ARRAY creates an array constant out of the following subexpressions.
       It is followed by two exp_elements, the first containing an integer
       that is the lower bound of the array and the second containing another
       integer that is the upper bound of the array.  The second integer is
       followed by a repeat of OP_ARRAY, making four exp_elements total.
       The bounds are used to compute the number of following subexpressions
       to consume, as well as setting the bounds in the created array constant.
       The type of the elements is taken from the type of the first subexp,
       and they must all match. */
    OP_ARRAY,

    /* UNOP_CAST is followed by a type pointer in the next exp_element.
       With another UNOP_CAST at the end, this makes three exp_elements.
       It casts the value of the following subexpression.  */
    UNOP_CAST,

    /* UNOP_MEMVAL is followed by a type pointer in the next exp_element
       With another UNOP_MEMVAL at the end, this makes three exp_elements.
       It casts the contents of the word addressed by the value of the
       following subexpression.  */
    UNOP_MEMVAL,

    /* UNOP_... operate on one value from a following subexpression
       and replace it with a result.  They take no immediate arguments.  */

    UNOP_NEG,			/* Unary - */
    UNOP_LOGICAL_NOT,		/* Unary ! */
    UNOP_COMPLEMENT,		/* Unary ~ */
    UNOP_IND,			/* Unary * */
    UNOP_ADDR,			/* Unary & */
    UNOP_PREINCREMENT,		/* ++ before an expression */
    UNOP_POSTINCREMENT,		/* ++ after an expression */
    UNOP_PREDECREMENT,		/* -- before an expression */
    UNOP_POSTDECREMENT,		/* -- after an expression */
    UNOP_SIZEOF,		/* Unary sizeof (followed by expression) */

    UNOP_PLUS,			/* Unary plus */

    UNOP_CAP,			/* Modula-2 standard (unary) procedures */
    UNOP_CHR,
    UNOP_ORD,
    UNOP_ABS,
    UNOP_FLOAT,
    UNOP_HIGH,
    UNOP_MAX,
    UNOP_MIN,
    UNOP_ODD,
    UNOP_TRUNC,

    /* (OBSOLETE) Chill (OBSOLETE) builtin functions. */
    UNOP_LOWER, UNOP_UPPER, UNOP_LENGTH, UNOP_CARD, UNOP_CHMAX, UNOP_CHMIN,

    OP_BOOL,			/* Modula-2 builtin BOOLEAN type */
    OP_M2_STRING,		/* Modula-2 string constants */

    /* STRUCTOP_... operate on a value from a following subexpression
       by extracting a structure component specified by a string
       that appears in the following exp_elements (as many as needed).
       STRUCTOP_STRUCT is used for "." and STRUCTOP_PTR for "->".
       They differ only in the error message given in case the value is
       not suitable or the structure component specified is not found.

       The length of the string follows the opcode, followed by
       BYTES_TO_EXP_ELEM(length) elements containing the data of the
       string, followed by the length again and the opcode again.  */

    STRUCTOP_STRUCT,
    STRUCTOP_PTR,

    /* C++ */
    /* OP_THIS is just a placeholder for the class instance variable.
       It just comes in a tight (OP_THIS, OP_THIS) pair.  */
    OP_THIS,

    /* OP_SCOPE surrounds a type name and a field name.  The type
       name is encoded as one element, but the field name stays as
       a string, which, of course, is variable length.  */
    OP_SCOPE,

    /* Used to represent named structure field values in brace
       initializers (or tuples as they are called in (OBSOLETE) Chill
       (OBSOLETE)).

       The gcc C syntax is NAME:VALUE or .NAME=VALUE, the (OBSOLETE)
       Chill (OBSOLETE) syntax is .NAME:VALUE.  Multiple labels (as in
       the (OBSOLETE) Chill (OBSOLETE) syntax .NAME1,.NAME2:VALUE) is
       represented as if it were .NAME1:(.NAME2:VALUE) (though that is
       not valid (OBSOLETE) Chill (OBSOLETE) syntax).

       The NAME is represented as for STRUCTOP_STRUCT;  VALUE follows. */
    OP_LABELED,

    /* OP_TYPE is for parsing types, and used with the "ptype" command
       so we can look up types that are qualified by scope, either with
       the GDB "::" operator, or the Modula-2 '.' operator. */
    OP_TYPE,

    /* An un-looked-up identifier. */
    OP_NAME,

    /* An unparsed expression.  Used for Scheme (for now at least) */
    OP_EXPRSTRING
  };

union exp_element
  {
    enum exp_opcode opcode;
    struct symbol *symbol;
    LONGEST longconst;
    DOUBLEST doubleconst;
    /* Really sizeof (union exp_element) characters (or less for the last
       element of a string).  */
    char string;
    struct type *type;
    struct internalvar *internalvar;
    struct block *block;
  };

struct expression
  {
    const struct language_defn *language_defn;	/* language it was entered in */
    int nelts;
    union exp_element elts[1];
  };

/* Macros for converting between number of expression elements and bytes
   to store that many expression elements. */

#define EXP_ELEM_TO_BYTES(elements) \
    ((elements) * sizeof (union exp_element))
#define BYTES_TO_EXP_ELEM(bytes) \
    (((bytes) + sizeof (union exp_element) - 1) / sizeof (union exp_element))

/* From parse.c */

extern struct expression *parse_expression (char *);

extern struct expression *parse_exp_1 (char **, struct block *, int);

/* The innermost context required by the stack and register variables
   we've encountered so far.  To use this, set it to NULL, then call
   parse_<whatever>, then look at it.  */
extern struct block *innermost_block;

/* From eval.c */

/* Values of NOSIDE argument to eval_subexp.  */

enum noside
  {
    EVAL_NORMAL,
    EVAL_SKIP,			/* Only effect is to increment pos.  */
    EVAL_AVOID_SIDE_EFFECTS	/* Don't modify any variables or
				   call any functions.  The value
				   returned will have the correct
				   type, and will have an
				   approximately correct lvalue
				   type (inaccuracy: anything that is
				   listed as being in a register in
				   the function in which it was
				   declared will be lval_register).  */
  };

extern struct value *evaluate_subexp_standard
  (struct type *, struct expression *, int *, enum noside);

/* From expprint.c */

extern void print_expression (struct expression *, struct ui_file *);

extern char *op_string (enum exp_opcode);

extern void dump_prefix_expression (struct expression *,
				    struct ui_file *,
				    char *);
extern void dump_postfix_expression (struct expression *,
				     struct ui_file *,
				     char *);

#endif /* !defined (EXPRESSION_H) */
Commit	Line	Data
c906108c	1	/* Definitions for expressions stored in reversed prefix form, for GDB.
d9fcf2fb	2	Copyright 1986, 1989, 1992, 1994, 2000 Free Software Foundation, Inc.
c906108c	3
c5aa993b	4	This file is part of GDB.
c906108c	5
c5aa993b JM	6	This program is free software; you can redistribute it and/or modify
	7	it under the terms of the GNU General Public License as published by
	8	the Free Software Foundation; either version 2 of the License, or
	9	(at your option) any later version.
c906108c	10
c5aa993b JM	11	This program is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	GNU General Public License for more details.
c906108c	15
c5aa993b JM	16	You should have received a copy of the GNU General Public License
	17	along with this program; if not, write to the Free Software
	18	Foundation, Inc., 59 Temple Place - Suite 330,
	19	Boston, MA 02111-1307, USA. */
c906108c SS	20
	21	#if !defined (EXPRESSION_H)
	22	#define EXPRESSION_H 1
	23
	24
c5aa993b	25	#include "symtab.h" /* Needed for "struct block" type. */
d16aafd8	26	#include "doublest.h" /* Needed for DOUBLEST. */
c906108c SS	27
	28
	29	/* Definitions for saved C expressions. */
	30
	31	/* An expression is represented as a vector of union exp_element's.
	32	Each exp_element is an opcode, except that some opcodes cause
	33	the following exp_element to be treated as a long or double constant
	34	or as a variable. The opcodes are obeyed, using a stack for temporaries.
	35	The value is left on the temporary stack at the end. */
	36
	37	/* When it is necessary to include a string,
	38	it can occupy as many exp_elements as it needs.
	39	We find the length of the string using strlen,
	40	divide to find out how many exp_elements are used up,
	41	and skip that many. Strings, like numbers, are indicated
	42	by the preceding opcode. */
	43
	44	enum exp_opcode
c5aa993b JM	45	{
	46	/* Used when it's necessary to pass an opcode which will be ignored,
	47	or to catch uninitialized values. */
	48	OP_NULL,
c906108c SS	49
	50	/* BINOP_... operate on two values computed by following subexpressions,
	51	replacing them by one result value. They take no immediate arguments. */
	52
c5aa993b JM	53	BINOP_ADD, /* + */
	54	BINOP_SUB, /* - */
	55	BINOP_MUL, /* * */
	56	BINOP_DIV, /* / */
	57	BINOP_REM, /* % */
	58	BINOP_MOD, /* mod (Knuth 1.2.4) */
	59	BINOP_LSH, /* << */
	60	BINOP_RSH, /* >> */
	61	BINOP_LOGICAL_AND, /* && */
	62	BINOP_LOGICAL_OR, /* \|\| */
	63	BINOP_BITWISE_AND, /* & */
	64	BINOP_BITWISE_IOR, /* \| */
	65	BINOP_BITWISE_XOR, /* ^ */
	66	BINOP_EQUAL, /* == */
	67	BINOP_NOTEQUAL, /* != */
	68	BINOP_LESS, /* < */
	69	BINOP_GTR, /* > */
	70	BINOP_LEQ, /* <= */
	71	BINOP_GEQ, /* >= */
	72	BINOP_REPEAT, /* @ */
	73	BINOP_ASSIGN, /* = */
	74	BINOP_COMMA, /* , */
	75	BINOP_SUBSCRIPT, /* x[y] */
	76	BINOP_EXP, /* Exponentiation */
	77
	78	/* C++. */
	79
	80	BINOP_MIN, /* <? */
	81	BINOP_MAX, /* >? */
c5aa993b JM	82
	83	/* STRUCTOP_MEMBER is used for pointer-to-member constructs.
	84	X . * Y translates into X STRUCTOP_MEMBER Y. */
	85	STRUCTOP_MEMBER,
	86
	87	/* STRUCTOP_MPTR is used for pointer-to-member constructs
	88	when X is a pointer instead of an aggregate. */
	89	STRUCTOP_MPTR,
	90
	91	/* end of C++. */
	92
	93	/* For Modula-2 integer division DIV */
	94	BINOP_INTDIV,
	95
	96	BINOP_ASSIGN_MODIFY, /* +=, -=, *=, and so on.
	97	The following exp_element is another opcode,
	98	a BINOP_, saying how to modify.
	99	Then comes another BINOP_ASSIGN_MODIFY,
	100	making three exp_elements in total. */
	101
	102	/* Modula-2 standard (binary) procedures */
	103	BINOP_VAL,
	104	BINOP_INCL,
	105	BINOP_EXCL,
	106
	107	/* Concatenate two operands, such as character strings or bitstrings.
	108	If the first operand is a integer expression, then it means concatenate
	109	the second operand with itself that many times. */
	110	BINOP_CONCAT,
	111
db034ac5	112	/* For (OBSOLETE) Chill (OBSOLETE) and Pascal. */
c5aa993b JM	113	BINOP_IN, /* Returns 1 iff ARG1 IN ARG2. */
c5aa993b JM	114
db034ac5 AC	115	/* This is the "colon operator" used various places in (OBSOLETE)
db034ac5 AC	116	Chill (OBSOLETE). */
c5aa993b JM	117	BINOP_RANGE,
	118
	119	/* This must be the highest BINOP_ value, for expprint.c. */
	120	BINOP_END,
	121
	122	/* Operates on three values computed by following subexpressions. */
	123	TERNOP_COND, /* ?: */
	124
db034ac5 AC	125	/* A sub-string/sub-array. (OBSOLETE) Chill (OBSOLETE) syntax:
db034ac5 AC	126	OP1(OP2:OP3). Return elements OP2 through OP3 of OP1. */
c5aa993b JM	127	TERNOP_SLICE,
c5aa993b JM	128
db034ac5 AC	129	/* A sub-string/sub-array. (OBSOLETE) Chill (OBSOLETE) syntax:
	130	OP1(OP2 UP OP3). Return OP3 elements of OP1, starting with
	131	element OP2. */
c5aa993b JM	132	TERNOP_SLICE_COUNT,
	133
	134	/* Multidimensional subscript operator, such as Modula-2 x[a,b,...].
	135	The dimensionality is encoded in the operator, like the number of
	136	function arguments in OP_FUNCALL, I.E. <OP><dimension><OP>.
	137	The value of the first following subexpression is subscripted
	138	by each of the next following subexpressions, one per dimension. */
	139	MULTI_SUBSCRIPT,
	140
	141	/* The OP_... series take immediate following arguments.
	142	After the arguments come another OP_... (the same one)
	143	so that the grouping can be recognized from the end. */
	144
	145	/* OP_LONG is followed by a type pointer in the next exp_element
	146	and the long constant value in the following exp_element.
	147	Then comes another OP_LONG.
	148	Thus, the operation occupies four exp_elements. */
	149	OP_LONG,
	150
	151	/* OP_DOUBLE is similar but takes a DOUBLEST constant instead of a long. */
	152	OP_DOUBLE,
	153
	154	/* OP_VAR_VALUE takes one struct block * in the following element,
	155	and one struct symbol * in the following exp_element, followed by
	156	another OP_VAR_VALUE, making four exp_elements. If the block is
	157	non-NULL, evaluate the symbol relative to the innermost frame
	158	executing in that block; if the block is NULL use the selected frame. */
	159	OP_VAR_VALUE,
	160
	161	/* OP_LAST is followed by an integer in the next exp_element.
	162	The integer is zero for the last value printed,
	163	or it is the absolute number of a history element.
	164	With another OP_LAST at the end, this makes three exp_elements. */
	165	OP_LAST,
	166
	167	/* OP_REGISTER is followed by an integer in the next exp_element.
	168	This is the number of a register to fetch (as an int).
	169	With another OP_REGISTER at the end, this makes three exp_elements. */
	170	OP_REGISTER,
	171
	172	/* OP_INTERNALVAR is followed by an internalvar ptr in the next exp_element.
	173	With another OP_INTERNALVAR at the end, this makes three exp_elements. */
	174	OP_INTERNALVAR,
	175
	176	/* OP_FUNCALL is followed by an integer in the next exp_element.
	177	The integer is the number of args to the function call.
	178	That many plus one values from following subexpressions
	179	are used, the first one being the function.
	180	The integer is followed by a repeat of OP_FUNCALL,
	181	making three exp_elements. */
	182	OP_FUNCALL,
	183
	184	/* This is EXACTLY like OP_FUNCALL but is semantically different.
	185	In F77, array subscript expressions, substring expressions
	186	and function calls are all exactly the same syntactically. They may
	187	only be dismabiguated at runtime. Thus this operator, which
	188	indicates that we have found something of the form <name> ( <stuff> ) */
	189	OP_F77_UNDETERMINED_ARGLIST,
	190
	191	/* The following OP is a special one, it introduces a F77 complex
	192	literal. It is followed by exactly two args that are doubles. */
	193	OP_COMPLEX,
	194
	195	/* OP_STRING represents a string constant.
196	Its format is the same as that of a STRUCTOP, but the string
197	data is just made into a string constant when the operation
198	is executed. */
199	OP_STRING,
200
201	/* OP_BITSTRING represents a packed bitstring constant.
202	Its format is the same as that of a STRUCTOP, but the bitstring
203	data is just made into a bitstring constant when the operation
204	is executed. */
205	OP_BITSTRING,
206
207	/* OP_ARRAY creates an array constant out of the following subexpressions.
208	It is followed by two exp_elements, the first containing an integer
209	that is the lower bound of the array and the second containing another
210	integer that is the upper bound of the array. The second integer is
211	followed by a repeat of OP_ARRAY, making four exp_elements total.
212	The bounds are used to compute the number of following subexpressions
213	to consume, as well as setting the bounds in the created array constant.
214	The type of the elements is taken from the type of the first subexp,
215	and they must all match. */
216	OP_ARRAY,
217
218	/* UNOP_CAST is followed by a type pointer in the next exp_element.
219	With another UNOP_CAST at the end, this makes three exp_elements.
220	It casts the value of the following subexpression. */
221	UNOP_CAST,
222
223	/* UNOP_MEMVAL is followed by a type pointer in the next exp_element
224	With another UNOP_MEMVAL at the end, this makes three exp_elements.
225	It casts the contents of the word addressed by the value of the
226	following subexpression. */
227	UNOP_MEMVAL,
228
229	/* UNOP_... operate on one value from a following subexpression
230	and replace it with a result. They take no immediate arguments. */
231
232	UNOP_NEG, /* Unary - */
233	UNOP_LOGICAL_NOT, /* Unary ! */
234	UNOP_COMPLEMENT, /* Unary ~ */
235	UNOP_IND, /* Unary * */
236	UNOP_ADDR, /* Unary & */
237	UNOP_PREINCREMENT, /* ++ before an expression */
238	UNOP_POSTINCREMENT, /* ++ after an expression */
239	UNOP_PREDECREMENT, /* -- before an expression */
240	UNOP_POSTDECREMENT, /* -- after an expression */
241	UNOP_SIZEOF, /* Unary sizeof (followed by expression) */
242
243	UNOP_PLUS, /* Unary plus */
244
245	UNOP_CAP, /* Modula-2 standard (unary) procedures */
246	UNOP_CHR,
247	UNOP_ORD,
248	UNOP_ABS,
249	UNOP_FLOAT,
250	UNOP_HIGH,
251	UNOP_MAX,
252	UNOP_MIN,
253	UNOP_ODD,
254	UNOP_TRUNC,
255
db034ac5	256	/* (OBSOLETE) Chill (OBSOLETE) builtin functions. */
c5aa993b JM	257	UNOP_LOWER, UNOP_UPPER, UNOP_LENGTH, UNOP_CARD, UNOP_CHMAX, UNOP_CHMIN,
	258
	259	OP_BOOL, /* Modula-2 builtin BOOLEAN type */
	260	OP_M2_STRING, /* Modula-2 string constants */
	261
	262	/* STRUCTOP_... operate on a value from a following subexpression
	263	by extracting a structure component specified by a string
	264	that appears in the following exp_elements (as many as needed).
	265	STRUCTOP_STRUCT is used for "." and STRUCTOP_PTR for "->".
	266	They differ only in the error message given in case the value is
	267	not suitable or the structure component specified is not found.
	268
	269	The length of the string follows the opcode, followed by
	270	BYTES_TO_EXP_ELEM(length) elements containing the data of the
	271	string, followed by the length again and the opcode again. */
	272
	273	STRUCTOP_STRUCT,
	274	STRUCTOP_PTR,
	275
	276	/* C++ */
	277	/* OP_THIS is just a placeholder for the class instance variable.
	278	It just comes in a tight (OP_THIS, OP_THIS) pair. */
	279	OP_THIS,
	280
	281	/* OP_SCOPE surrounds a type name and a field name. The type
	282	name is encoded as one element, but the field name stays as
	283	a string, which, of course, is variable length. */
	284	OP_SCOPE,
	285
db034ac5 AC	286	/* Used to represent named structure field values in brace
	287	initializers (or tuples as they are called in (OBSOLETE) Chill
	288	(OBSOLETE)).
	289
	290	The gcc C syntax is NAME:VALUE or .NAME=VALUE, the (OBSOLETE)
	291	Chill (OBSOLETE) syntax is .NAME:VALUE. Multiple labels (as in
	292	the (OBSOLETE) Chill (OBSOLETE) syntax .NAME1,.NAME2:VALUE) is
	293	represented as if it were .NAME1:(.NAME2:VALUE) (though that is
	294	not valid (OBSOLETE) Chill (OBSOLETE) syntax).
c5aa993b JM	295
	296	The NAME is represented as for STRUCTOP_STRUCT; VALUE follows. */
	297	OP_LABELED,
	298
	299	/* OP_TYPE is for parsing types, and used with the "ptype" command
	300	so we can look up types that are qualified by scope, either with
	301	the GDB "::" operator, or the Modula-2 '.' operator. */
	302	OP_TYPE,
	303
	304	/* An un-looked-up identifier. */
	305	OP_NAME,
	306
	307	/* An unparsed expression. Used for Scheme (for now at least) */
	308	OP_EXPRSTRING
	309	};
c906108c SS	310
c906108c SS	311	union exp_element
c5aa993b JM	312	{
	313	enum exp_opcode opcode;
	314	struct symbol *symbol;
	315	LONGEST longconst;
	316	DOUBLEST doubleconst;
	317	/* Really sizeof (union exp_element) characters (or less for the last
	318	element of a string). */
	319	char string;
	320	struct type *type;
	321	struct internalvar *internalvar;
	322	struct block *block;
	323	};
c906108c SS	324
c906108c SS	325	struct expression
c5aa993b JM	326	{
	327	const struct language_defn language_defn; / language it was entered in */
	328	int nelts;
	329	union exp_element elts[1];
	330	};
c906108c SS	331
	332	/* Macros for converting between number of expression elements and bytes
	333	to store that many expression elements. */
	334
	335	#define EXP_ELEM_TO_BYTES(elements) \
	336	((elements) * sizeof (union exp_element))
	337	#define BYTES_TO_EXP_ELEM(bytes) \
	338	(((bytes) + sizeof (union exp_element) - 1) / sizeof (union exp_element))
	339
	340	/* From parse.c */
	341
a14ed312	342	extern struct expression parse_expression (char );
c906108c	343
a14ed312	344	extern struct expression parse_exp_1 (char , struct block , int);
c906108c SS	345
	346	/* The innermost context required by the stack and register variables
	347	we've encountered so far. To use this, set it to NULL, then call
	348	parse_<whatever>, then look at it. */
	349	extern struct block *innermost_block;
	350
	351	/* From eval.c */
	352
	353	/* Values of NOSIDE argument to eval_subexp. */
	354
	355	enum noside
c5aa993b JM	356	{
	357	EVAL_NORMAL,
	358	EVAL_SKIP, /* Only effect is to increment pos. */
	359	EVAL_AVOID_SIDE_EFFECTS /* Don't modify any variables or
c906108c SS	360	call any functions. The value
	361	returned will have the correct
	362	type, and will have an
	363	approximately correct lvalue
	364	type (inaccuracy: anything that is
	365	listed as being in a register in
	366	the function in which it was
	367	declared will be lval_register). */
c5aa993b	368	};
c906108c	369
c5aa993b	370	extern struct value *evaluate_subexp_standard
a14ed312	371	(struct type , struct expression , int *, enum noside);
c906108c SS	372
	373	/* From expprint.c */
	374
d9fcf2fb	375	extern void print_expression (struct expression , struct ui_file );
c906108c	376
a14ed312	377	extern char *op_string (enum exp_opcode);
c906108c	378
d9fcf2fb JM	379	extern void dump_prefix_expression (struct expression *,
	380	struct ui_file *,
	381	char *);
	382	extern void dump_postfix_expression (struct expression *,
	383	struct ui_file *,
	384	char *);
c906108c	385
c5aa993b	386	#endif /* !defined (EXPRESSION_H) */