1066 lines
30 KiB
C
1066 lines
30 KiB
C
/*-
|
||
* This code is derived from software copyrighted by the Free Software
|
||
* Foundation.
|
||
*
|
||
* Modified 1991 by Donn Seeley at UUNET Technologies, Inc.
|
||
* Modified 1990 by Van Jacobson at Lawrence Berkeley Laboratory.
|
||
*/
|
||
|
||
#ifndef lint
|
||
static char sccsid[] = "@(#)eval.c 6.3 (Berkeley) 5/8/91";
|
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#endif /* not lint */
|
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|
||
/* Evaluate expressions for GDB.
|
||
Copyright (C) 1986, 1987, 1989 Free Software Foundation, Inc.
|
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|
||
This file is part of GDB.
|
||
|
||
GDB is free software; you can redistribute it and/or modify
|
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it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 1, or (at your option)
|
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any later version.
|
||
|
||
GDB 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 GDB; see the file COPYING. If not, write to
|
||
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
|
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|
||
#include "defs.h"
|
||
#include "param.h"
|
||
#include "symtab.h"
|
||
#include "value.h"
|
||
#include "expression.h"
|
||
|
||
|
||
/* Parse the string EXP as a C expression, evaluate it,
|
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and return the result as a number. */
|
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|
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CORE_ADDR
|
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parse_and_eval_address (exp)
|
||
char *exp;
|
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{
|
||
struct expression *expr = parse_c_expression (exp);
|
||
register CORE_ADDR addr;
|
||
register struct cleanup *old_chain
|
||
= make_cleanup (free_current_contents, &expr);
|
||
|
||
addr = (CORE_ADDR) value_as_long (evaluate_expression (expr));
|
||
do_cleanups (old_chain);
|
||
return addr;
|
||
}
|
||
|
||
/* Like parse_and_eval_address but takes a pointer to a char * variable
|
||
and advanced that variable across the characters parsed. */
|
||
|
||
CORE_ADDR
|
||
parse_and_eval_address_1 (expptr)
|
||
char **expptr;
|
||
{
|
||
struct expression *expr = parse_c_1 (expptr, 0, 0);
|
||
register CORE_ADDR addr;
|
||
register struct cleanup *old_chain
|
||
= make_cleanup (free_current_contents, &expr);
|
||
|
||
addr = value_as_long (evaluate_expression (expr));
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||
do_cleanups (old_chain);
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||
return addr;
|
||
}
|
||
|
||
value
|
||
parse_and_eval (exp)
|
||
char *exp;
|
||
{
|
||
struct expression *expr = parse_c_expression (exp);
|
||
register value val;
|
||
register struct cleanup *old_chain
|
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= make_cleanup (free_current_contents, &expr);
|
||
|
||
val = evaluate_expression (expr);
|
||
do_cleanups (old_chain);
|
||
return val;
|
||
}
|
||
|
||
/* Parse up to a comma (or to a closeparen)
|
||
in the string EXPP as an expression, evaluate it, and return the value.
|
||
EXPP is advanced to point to the comma. */
|
||
|
||
value
|
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parse_to_comma_and_eval (expp)
|
||
char **expp;
|
||
{
|
||
struct expression *expr = parse_c_1 (expp, 0, 1);
|
||
register value val;
|
||
register struct cleanup *old_chain
|
||
= make_cleanup (free_current_contents, &expr);
|
||
|
||
val = evaluate_expression (expr);
|
||
do_cleanups (old_chain);
|
||
return val;
|
||
}
|
||
|
||
/* Evaluate an expression in internal prefix form
|
||
such as is constructed by expread.y.
|
||
|
||
See expression.h for info on the format of an expression. */
|
||
|
||
static value evaluate_subexp ();
|
||
static value evaluate_subexp_for_address ();
|
||
static value evaluate_subexp_for_sizeof ();
|
||
static value evaluate_subexp_with_coercion ();
|
||
|
||
/* return true if 'var' has an address in inferior's memory. */
|
||
static int
|
||
value_has_lval(var)
|
||
register struct symbol *var;
|
||
{
|
||
switch (SYMBOL_CLASS(var))
|
||
{
|
||
case LOC_STATIC:
|
||
case LOC_LABEL:
|
||
case LOC_ARG:
|
||
case LOC_REF_ARG:
|
||
case LOC_LOCAL:
|
||
case LOC_BLOCK:
|
||
return (1);
|
||
}
|
||
return (0);
|
||
}
|
||
|
||
/* Values of NOSIDE argument to eval_subexp. */
|
||
enum noside
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||
{ 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
|
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the function in which it was
|
||
declared will be lval_register). */
|
||
};
|
||
|
||
value
|
||
evaluate_expression (exp)
|
||
struct expression *exp;
|
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{
|
||
int pc = 0;
|
||
return evaluate_subexp (0, exp, &pc, EVAL_NORMAL);
|
||
}
|
||
|
||
/* Evaluate an expression, avoiding all memory references
|
||
and getting a value whose type alone is correct. */
|
||
|
||
value
|
||
evaluate_type (exp)
|
||
struct expression *exp;
|
||
{
|
||
int pc = 0;
|
||
return evaluate_subexp (0, exp, &pc, EVAL_AVOID_SIDE_EFFECTS);
|
||
}
|
||
|
||
static value
|
||
evaluate_subexp (expect_type, exp, pos, noside)
|
||
struct type *expect_type;
|
||
register struct expression *exp;
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register int *pos;
|
||
enum noside noside;
|
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{
|
||
enum exp_opcode op;
|
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int tem;
|
||
register int pc, pc2, oldpos;
|
||
register value arg1, arg2, arg3;
|
||
int nargs;
|
||
value *argvec;
|
||
|
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pc = (*pos)++;
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op = exp->elts[pc].opcode;
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||
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switch (op)
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||
{
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||
case OP_SCOPE:
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tem = strlen (&exp->elts[pc + 2].string);
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(*pos) += 3 + ((tem + sizeof (union exp_element))
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/ sizeof (union exp_element));
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||
return value_static_field (exp->elts[pc + 1].type,
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&exp->elts[pc + 2].string, -1);
|
||
|
||
case OP_LONG:
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||
(*pos) += 3;
|
||
return value_from_long (exp->elts[pc + 1].type,
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exp->elts[pc + 2].longconst);
|
||
|
||
case OP_DOUBLE:
|
||
(*pos) += 3;
|
||
return value_from_double (exp->elts[pc + 1].type,
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||
exp->elts[pc + 2].doubleconst);
|
||
|
||
case OP_VAR_VALUE:
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||
(*pos) += 2;
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||
if (noside == EVAL_SKIP)
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||
goto nosideret;
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
{
|
||
struct symbol * sym = exp->elts[pc + 1].symbol;
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||
enum lval_type lv;
|
||
|
||
switch (SYMBOL_CLASS (sym))
|
||
{
|
||
case LOC_CONST:
|
||
case LOC_LABEL:
|
||
case LOC_CONST_BYTES:
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||
lv = not_lval;
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||
case LOC_REGISTER:
|
||
case LOC_REGPARM:
|
||
lv = lval_register;
|
||
default:
|
||
lv = lval_memory;
|
||
}
|
||
|
||
return value_zero (SYMBOL_TYPE (sym), lv);
|
||
}
|
||
else
|
||
return value_of_variable (exp->elts[pc + 1].symbol);
|
||
|
||
case OP_LAST:
|
||
(*pos) += 2;
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||
return access_value_history ((int) exp->elts[pc + 1].longconst);
|
||
|
||
case OP_REGISTER:
|
||
(*pos) += 2;
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||
return value_of_register ((int) exp->elts[pc + 1].longconst);
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||
|
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case OP_INTERNALVAR:
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||
(*pos) += 2;
|
||
return value_of_internalvar (exp->elts[pc + 1].internalvar);
|
||
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||
case OP_STRING:
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tem = strlen (&exp->elts[pc + 1].string);
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(*pos) += 2 + ((tem + sizeof (union exp_element))
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||
/ sizeof (union exp_element));
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if (noside == EVAL_SKIP)
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goto nosideret;
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||
return value_string (&exp->elts[pc + 1].string, tem);
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||
|
||
case TERNOP_COND:
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/* Skip third and second args to evaluate the first one. */
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arg1 = evaluate_subexp (0, exp, pos, noside);
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if (value_zerop (arg1))
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{
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evaluate_subexp (0, exp, pos, EVAL_SKIP);
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return evaluate_subexp (0, exp, pos, noside);
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}
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else
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{
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arg2 = evaluate_subexp (0, exp, pos, noside);
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||
evaluate_subexp (0, exp, pos, EVAL_SKIP);
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||
return arg2;
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||
}
|
||
|
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case OP_FUNCALL:
|
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(*pos) += 2;
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||
op = exp->elts[*pos].opcode;
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||
if (op == STRUCTOP_MEMBER || op == STRUCTOP_MPTR)
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||
{
|
||
int fnptr;
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||
int tem2;
|
||
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||
nargs = (int) exp->elts[pc + 1].longconst + 1;
|
||
/* First, evaluate the structure into arg2 */
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pc2 = (*pos)++;
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||
|
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if (noside == EVAL_SKIP)
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goto nosideret;
|
||
|
||
if (op == STRUCTOP_MEMBER)
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||
{
|
||
arg2 = evaluate_subexp_for_address (exp, pos, noside);
|
||
}
|
||
else
|
||
{
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||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
}
|
||
|
||
/* If the function is a virtual function, then the
|
||
aggregate value (providing the structure) plays
|
||
its part by providing the vtable. Otherwise,
|
||
it is just along for the ride: call the function
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||
directly. */
|
||
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
|
||
fnptr = (int) value_as_long (arg1);
|
||
if (fnptr < 128)
|
||
{
|
||
struct type *basetype;
|
||
int i, j;
|
||
basetype = TYPE_TARGET_TYPE (VALUE_TYPE (arg2));
|
||
basetype = TYPE_VPTR_BASETYPE (basetype);
|
||
for (i = TYPE_NFN_FIELDS (basetype) - 1; i >= 0; i--)
|
||
{
|
||
struct fn_field *f = TYPE_FN_FIELDLIST1 (basetype, i);
|
||
/* If one is virtual, then all are virtual. */
|
||
if (TYPE_FN_FIELD_VIRTUAL_P (f, 0))
|
||
for (j = TYPE_FN_FIELDLIST_LENGTH (basetype, i) - 1; j >= 0; --j)
|
||
if (TYPE_FN_FIELD_VOFFSET (f, j) == fnptr)
|
||
{
|
||
value vtbl;
|
||
value base = value_ind (arg2);
|
||
struct type *fntype = lookup_pointer_type (TYPE_FN_FIELD_TYPE (f, j));
|
||
|
||
if (TYPE_VPTR_FIELDNO (basetype) < 0)
|
||
TYPE_VPTR_FIELDNO (basetype)
|
||
= fill_in_vptr_fieldno (basetype);
|
||
|
||
VALUE_TYPE (base) = basetype;
|
||
vtbl = value_field (base, TYPE_VPTR_FIELDNO (basetype));
|
||
VALUE_TYPE (vtbl) = lookup_pointer_type (fntype);
|
||
VALUE_TYPE (arg1) = builtin_type_int;
|
||
arg1 = value_subscript (vtbl, arg1);
|
||
VALUE_TYPE (arg1) = fntype;
|
||
goto got_it;
|
||
}
|
||
}
|
||
if (i < 0)
|
||
error ("virtual function at index %d not found", fnptr);
|
||
}
|
||
else
|
||
{
|
||
VALUE_TYPE (arg1) = lookup_pointer_type (TYPE_TARGET_TYPE (VALUE_TYPE (arg1)));
|
||
}
|
||
got_it:
|
||
|
||
/* Now, say which argument to start evaluating from */
|
||
tem = 2;
|
||
}
|
||
else if (op == STRUCTOP_STRUCT || op == STRUCTOP_PTR)
|
||
{
|
||
/* Hair for method invocations */
|
||
int tem2;
|
||
|
||
nargs = (int) exp->elts[pc + 1].longconst + 1;
|
||
/* First, evaluate the structure into arg2 */
|
||
pc2 = (*pos)++;
|
||
tem2 = strlen (&exp->elts[pc2 + 1].string);
|
||
*pos += 2 + (tem2 + sizeof (union exp_element)) / sizeof (union exp_element);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
|
||
if (op == STRUCTOP_STRUCT)
|
||
{
|
||
arg2 = evaluate_subexp_for_address (exp, pos, noside);
|
||
}
|
||
else
|
||
{
|
||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
}
|
||
/* Now, say which argument to start evaluating from */
|
||
tem = 2;
|
||
}
|
||
else
|
||
{
|
||
nargs = (int) exp->elts[pc + 1].longconst;
|
||
tem = 0;
|
||
}
|
||
argvec = (value *) alloca (sizeof (value) * (nargs + 2));
|
||
for (; tem <= nargs; tem++)
|
||
/* Ensure that array expressions are coerced into pointer objects. */
|
||
argvec[tem] = evaluate_subexp_with_coercion (exp, pos, noside);
|
||
|
||
/* signal end of arglist */
|
||
argvec[tem] = 0;
|
||
|
||
if (op == STRUCTOP_STRUCT || op == STRUCTOP_PTR)
|
||
{
|
||
int static_memfuncp;
|
||
|
||
argvec[1] = arg2;
|
||
argvec[0] =
|
||
value_struct_elt (arg2, argvec+1, &exp->elts[pc2 + 1].string,
|
||
&static_memfuncp,
|
||
op == STRUCTOP_STRUCT
|
||
? "structure" : "structure pointer");
|
||
if (static_memfuncp)
|
||
{
|
||
argvec[1] = argvec[0];
|
||
nargs--;
|
||
argvec++;
|
||
}
|
||
}
|
||
else if (op == STRUCTOP_MEMBER || op == STRUCTOP_MPTR)
|
||
{
|
||
argvec[1] = arg2;
|
||
argvec[0] = arg1;
|
||
}
|
||
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
{
|
||
/* If the return type doesn't look like a function type, call an
|
||
error. This can happen if somebody tries to turn a variable into
|
||
a function call. This is here because people often want to
|
||
call, eg, strcmp, which gdb doesn't know is a function. If
|
||
gdb isn't asked for it's opinion (ie. through "whatis"),
|
||
it won't offer it. */
|
||
|
||
struct type *ftype =
|
||
TYPE_TARGET_TYPE (VALUE_TYPE (argvec[0]));
|
||
|
||
if (ftype)
|
||
return allocate_value (TYPE_TARGET_TYPE (VALUE_TYPE (argvec[0])));
|
||
else
|
||
error ("Expression of type other than \"Function returning ...\" used as function");
|
||
}
|
||
return call_function (argvec[0], nargs, argvec + 1);
|
||
|
||
case STRUCTOP_STRUCT:
|
||
tem = strlen (&exp->elts[pc + 1].string);
|
||
(*pos) += 2 + ((tem + sizeof (union exp_element))
|
||
/ sizeof (union exp_element));
|
||
|
||
/* Try to convert "foo.bar" into "(&foo)->bar" so we won't copy
|
||
* the entire contents of a large struct just to extract one
|
||
* value from it. */
|
||
if (noside == EVAL_NORMAL && exp->elts[*pos].opcode == OP_VAR_VALUE
|
||
&& value_has_lval(exp->elts[*pos + 1].symbol))
|
||
arg1 = evaluate_subexp_for_address(exp, pos, noside);
|
||
else
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
{
|
||
register struct type *type = VALUE_TYPE (arg1);
|
||
if (TYPE_CODE (type) == TYPE_CODE_PTR)
|
||
type = TYPE_TARGET_TYPE (type);
|
||
return value_zero (lookup_struct_elt_type (type,
|
||
&exp->elts[pc + 1].string),
|
||
lval_memory);
|
||
}
|
||
else
|
||
return value_struct_elt (arg1, 0, &exp->elts[pc + 1].string, 0,
|
||
"structure");
|
||
|
||
case STRUCTOP_PTR:
|
||
tem = strlen (&exp->elts[pc + 1].string);
|
||
(*pos) += 2 + (tem + sizeof (union exp_element)) / sizeof (union exp_element);
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return value_zero (lookup_struct_elt_type (TYPE_TARGET_TYPE
|
||
(VALUE_TYPE (arg1)),
|
||
&exp->elts[pc + 1].string),
|
||
lval_memory);
|
||
else
|
||
return value_struct_elt (arg1, 0, &exp->elts[pc + 1].string, 0,
|
||
"structure pointer");
|
||
|
||
case STRUCTOP_MEMBER:
|
||
arg1 = evaluate_subexp_for_address (exp, pos, noside);
|
||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
/* Now, convert these values to an address. */
|
||
if (TYPE_CODE (VALUE_TYPE (arg2)) != TYPE_CODE_PTR
|
||
|| ((TYPE_CODE (TYPE_TARGET_TYPE (VALUE_TYPE (arg2)))
|
||
!= TYPE_CODE_MEMBER)
|
||
&& (TYPE_CODE (TYPE_TARGET_TYPE (VALUE_TYPE (arg2)))
|
||
!= TYPE_CODE_METHOD)))
|
||
error ("non-pointer-to-member value used in pointer-to-member construct");
|
||
arg3 = value_from_long (builtin_type_long,
|
||
value_as_long (arg1) + value_as_long (arg2));
|
||
VALUE_TYPE (arg3) =
|
||
lookup_pointer_type (TYPE_TARGET_TYPE (TYPE_TARGET_TYPE (VALUE_TYPE (arg2))));
|
||
return value_ind (arg3);
|
||
|
||
case STRUCTOP_MPTR:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
/* Now, convert these values to an address. */
|
||
if (TYPE_CODE (VALUE_TYPE (arg2)) != TYPE_CODE_PTR
|
||
|| (TYPE_CODE (TYPE_TARGET_TYPE (VALUE_TYPE (arg2))) != TYPE_CODE_MEMBER
|
||
&& TYPE_CODE (TYPE_TARGET_TYPE (VALUE_TYPE (arg2))) != TYPE_CODE_METHOD))
|
||
error ("non-pointer-to-member value used in pointer-to-member construct");
|
||
arg3 = value_from_long (builtin_type_long,
|
||
value_as_long (arg1) + value_as_long (arg2));
|
||
VALUE_TYPE (arg3) =
|
||
lookup_pointer_type (TYPE_TARGET_TYPE (TYPE_TARGET_TYPE (VALUE_TYPE (arg2))));
|
||
return value_ind (arg3);
|
||
|
||
case BINOP_ASSIGN:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside);
|
||
if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return arg1;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
else
|
||
return value_assign (arg1, arg2);
|
||
|
||
case BINOP_ASSIGN_MODIFY:
|
||
(*pos) += 2;
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside);
|
||
if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return arg1;
|
||
op = exp->elts[pc + 1].opcode;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
return value_x_binop (arg1, arg2, BINOP_ASSIGN_MODIFY, op);
|
||
else if (op == BINOP_ADD)
|
||
arg2 = value_add (arg1, arg2);
|
||
else if (op == BINOP_SUB)
|
||
arg2 = value_sub (arg1, arg2);
|
||
else
|
||
arg2 = value_binop (arg1, arg2, op);
|
||
return value_assign (arg1, arg2);
|
||
|
||
case BINOP_ADD:
|
||
arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
|
||
arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
else
|
||
return value_add (arg1, arg2);
|
||
|
||
case BINOP_SUB:
|
||
arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
|
||
arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
else
|
||
return value_sub (arg1, arg2);
|
||
|
||
case BINOP_MUL:
|
||
case BINOP_DIV:
|
||
case BINOP_REM:
|
||
case BINOP_LSH:
|
||
case BINOP_RSH:
|
||
case BINOP_LOGAND:
|
||
case BINOP_LOGIOR:
|
||
case BINOP_LOGXOR:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
else
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS
|
||
&& op == BINOP_DIV)
|
||
return value_zero (VALUE_TYPE (arg1), not_lval);
|
||
else
|
||
return value_binop (arg1, arg2, op);
|
||
|
||
case BINOP_SUBSCRIPT:
|
||
arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
|
||
arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return value_zero (TYPE_TARGET_TYPE (VALUE_TYPE (arg1)),
|
||
VALUE_LVAL (arg1));
|
||
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
else
|
||
return value_subscript (arg1, arg2);
|
||
|
||
case BINOP_AND:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
{
|
||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
goto nosideret;
|
||
}
|
||
|
||
oldpos = *pos;
|
||
arg2 = evaluate_subexp (0, exp, pos, EVAL_AVOID_SIDE_EFFECTS);
|
||
*pos = oldpos;
|
||
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
{
|
||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
}
|
||
else
|
||
{
|
||
tem = value_zerop (arg1);
|
||
arg2 = evaluate_subexp (0, exp, pos,
|
||
(tem ? EVAL_SKIP : noside));
|
||
return value_from_long (builtin_type_int,
|
||
(LONGEST) (!tem && !value_zerop (arg2)));
|
||
}
|
||
|
||
case BINOP_OR:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
{
|
||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
goto nosideret;
|
||
}
|
||
|
||
oldpos = *pos;
|
||
arg2 = evaluate_subexp (0, exp, pos, EVAL_AVOID_SIDE_EFFECTS);
|
||
*pos = oldpos;
|
||
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
{
|
||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
}
|
||
else
|
||
{
|
||
tem = value_zerop (arg1);
|
||
arg2 = evaluate_subexp (0, exp, pos,
|
||
(!tem ? EVAL_SKIP : noside));
|
||
return value_from_long (builtin_type_int,
|
||
(LONGEST) (!tem || !value_zerop (arg2)));
|
||
}
|
||
|
||
case BINOP_EQUAL:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
{
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
}
|
||
else
|
||
{
|
||
tem = value_equal (arg1, arg2);
|
||
return value_from_long (builtin_type_int, (LONGEST) tem);
|
||
}
|
||
|
||
case BINOP_NOTEQUAL:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
{
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
}
|
||
else
|
||
{
|
||
tem = value_equal (arg1, arg2);
|
||
return value_from_long (builtin_type_int, (LONGEST) ! tem);
|
||
}
|
||
|
||
case BINOP_LESS:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
{
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
}
|
||
else
|
||
{
|
||
tem = value_less (arg1, arg2);
|
||
return value_from_long (builtin_type_int, (LONGEST) tem);
|
||
}
|
||
|
||
case BINOP_GTR:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
{
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
}
|
||
else
|
||
{
|
||
tem = value_less (arg2, arg1);
|
||
return value_from_long (builtin_type_int, (LONGEST) tem);
|
||
}
|
||
|
||
case BINOP_GEQ:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
{
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
}
|
||
else
|
||
{
|
||
tem = value_less (arg1, arg2);
|
||
return value_from_long (builtin_type_int, (LONGEST) ! tem);
|
||
}
|
||
|
||
case BINOP_LEQ:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (VALUE_TYPE (arg1), exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (binop_user_defined_p (op, arg1, arg2))
|
||
{
|
||
return value_x_binop (arg1, arg2, op, 0);
|
||
}
|
||
else
|
||
{
|
||
tem = value_less (arg2, arg1);
|
||
return value_from_long (builtin_type_int, (LONGEST) ! tem);
|
||
}
|
||
|
||
case BINOP_REPEAT:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
arg2 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (TYPE_CODE (VALUE_TYPE (arg2)) != TYPE_CODE_INT)
|
||
error ("Non-integral right operand for \"@\" operator.");
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return allocate_repeat_value (VALUE_TYPE (arg1),
|
||
(int) value_as_long (arg2));
|
||
else
|
||
return value_repeat (arg1, (int) value_as_long (arg2));
|
||
|
||
case BINOP_COMMA:
|
||
evaluate_subexp (0, exp, pos, noside);
|
||
return evaluate_subexp (0, exp, pos, noside);
|
||
|
||
case UNOP_NEG:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (unop_user_defined_p (op, arg1))
|
||
return value_x_unop (arg1, op);
|
||
else
|
||
return value_neg (arg1);
|
||
|
||
case UNOP_LOGNOT:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (unop_user_defined_p (op, arg1))
|
||
return value_x_unop (arg1, op);
|
||
else
|
||
return value_lognot (arg1);
|
||
|
||
case UNOP_ZEROP:
|
||
arg1 = evaluate_subexp (0, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (unop_user_defined_p (op, arg1))
|
||
return value_x_unop (arg1, op);
|
||
else
|
||
return value_from_long (builtin_type_int,
|
||
(LONGEST) value_zerop (arg1));
|
||
|
||
case UNOP_IND:
|
||
if (expect_type && TYPE_CODE (expect_type) == TYPE_CODE_PTR)
|
||
expect_type = TYPE_TARGET_TYPE (expect_type);
|
||
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
{
|
||
if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_PTR
|
||
|| TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_REF
|
||
/* In C you can dereference an array to get the 1st elt. */
|
||
|| TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_ARRAY
|
||
)
|
||
return value_zero (TYPE_TARGET_TYPE (VALUE_TYPE (arg1)),
|
||
lval_memory);
|
||
else if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_INT)
|
||
/* GDB allows dereferencing an int. */
|
||
return value_zero (builtin_type_int, lval_memory);
|
||
else
|
||
error ("Attempt to take contents of a non-pointer value.");
|
||
}
|
||
return value_ind (arg1);
|
||
|
||
case UNOP_ADDR:
|
||
/* C++: check for and handle pointer to members. */
|
||
|
||
op = exp->elts[*pos].opcode;
|
||
|
||
if (noside == EVAL_SKIP)
|
||
{
|
||
if (op == OP_SCOPE)
|
||
{
|
||
char *name = &exp->elts[pc+3].string;
|
||
int tem = strlen (name);
|
||
(*pos) += 2 + (tem + sizeof (union exp_element)) / sizeof (union exp_element);
|
||
}
|
||
else
|
||
evaluate_subexp (expect_type, exp, pos, EVAL_SKIP);
|
||
goto nosideret;
|
||
}
|
||
|
||
if (op == OP_SCOPE)
|
||
{
|
||
char *name = &exp->elts[pc+3].string;
|
||
int tem = strlen (name);
|
||
struct type *domain = exp->elts[pc+2].type;
|
||
(*pos) += 2 + (tem + sizeof (union exp_element)) / sizeof (union exp_element);
|
||
arg1 = value_struct_elt_for_address (domain, expect_type, name);
|
||
if (arg1)
|
||
return arg1;
|
||
error ("no field `%s' in structure", name);
|
||
}
|
||
else
|
||
return evaluate_subexp_for_address (exp, pos, noside);
|
||
|
||
case UNOP_SIZEOF:
|
||
if (noside == EVAL_SKIP)
|
||
{
|
||
evaluate_subexp (0, exp, pos, EVAL_SKIP);
|
||
goto nosideret;
|
||
}
|
||
return evaluate_subexp_for_sizeof (exp, pos);
|
||
|
||
case UNOP_CAST:
|
||
(*pos) += 2;
|
||
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
return value_cast (exp->elts[pc + 1].type, arg1);
|
||
|
||
case UNOP_MEMVAL:
|
||
(*pos) += 2;
|
||
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
|
||
if (noside == EVAL_SKIP)
|
||
goto nosideret;
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return value_zero (exp->elts[pc + 1].type, lval_memory);
|
||
else
|
||
return value_at (exp->elts[pc + 1].type,
|
||
(CORE_ADDR) value_as_long (arg1));
|
||
|
||
case UNOP_PREINCREMENT:
|
||
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
|
||
if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return arg1;
|
||
else if (unop_user_defined_p (op, arg1))
|
||
{
|
||
return value_x_unop (arg1, op);
|
||
}
|
||
else
|
||
{
|
||
arg2 = value_add (arg1, value_from_long (builtin_type_char,
|
||
(LONGEST) 1));
|
||
return value_assign (arg1, arg2);
|
||
}
|
||
|
||
case UNOP_PREDECREMENT:
|
||
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
|
||
if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return arg1;
|
||
else if (unop_user_defined_p (op, arg1))
|
||
{
|
||
return value_x_unop (arg1, op);
|
||
}
|
||
else
|
||
{
|
||
arg2 = value_sub (arg1, value_from_long (builtin_type_char,
|
||
(LONGEST) 1));
|
||
return value_assign (arg1, arg2);
|
||
}
|
||
|
||
case UNOP_POSTINCREMENT:
|
||
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
|
||
if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return arg1;
|
||
else if (unop_user_defined_p (op, arg1))
|
||
{
|
||
return value_x_unop (arg1, op);
|
||
}
|
||
else
|
||
{
|
||
arg2 = value_add (arg1, value_from_long (builtin_type_char,
|
||
(LONGEST) 1));
|
||
value_assign (arg1, arg2);
|
||
return arg1;
|
||
}
|
||
|
||
case UNOP_POSTDECREMENT:
|
||
arg1 = evaluate_subexp (expect_type, exp, pos, noside);
|
||
if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
return arg1;
|
||
else if (unop_user_defined_p (op, arg1))
|
||
{
|
||
return value_x_unop (arg1, op);
|
||
}
|
||
else
|
||
{
|
||
arg2 = value_sub (arg1, value_from_long (builtin_type_char,
|
||
(LONGEST) 1));
|
||
value_assign (arg1, arg2);
|
||
return arg1;
|
||
}
|
||
|
||
case OP_THIS:
|
||
(*pos) += 1;
|
||
return value_of_this (1);
|
||
|
||
default:
|
||
error ("internal error: I do not know how to evaluate what you gave me");
|
||
}
|
||
|
||
nosideret:
|
||
return value_from_long (builtin_type_long, (LONGEST) 1);
|
||
}
|
||
|
||
/* Evaluate a subexpression of EXP, at index *POS,
|
||
and return the address of that subexpression.
|
||
Advance *POS over the subexpression.
|
||
If the subexpression isn't an lvalue, get an error.
|
||
NOSIDE may be EVAL_AVOID_SIDE_EFFECTS;
|
||
then only the type of the result need be correct. */
|
||
|
||
static value
|
||
evaluate_subexp_for_address (exp, pos, noside)
|
||
register struct expression *exp;
|
||
register int *pos;
|
||
enum noside noside;
|
||
{
|
||
enum exp_opcode op;
|
||
register int pc;
|
||
|
||
pc = (*pos);
|
||
op = exp->elts[pc].opcode;
|
||
|
||
switch (op)
|
||
{
|
||
case UNOP_IND:
|
||
(*pos)++;
|
||
return evaluate_subexp (0, exp, pos, noside);
|
||
|
||
case UNOP_MEMVAL:
|
||
(*pos) += 3;
|
||
return value_cast (lookup_pointer_type (exp->elts[pc + 1].type),
|
||
evaluate_subexp (0, exp, pos, noside));
|
||
|
||
case OP_VAR_VALUE:
|
||
(*pos) += 3;
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
{
|
||
struct type *type =
|
||
lookup_pointer_type (SYMBOL_TYPE (exp->elts[pc + 1].symbol));
|
||
enum address_class sym_class =
|
||
SYMBOL_CLASS (exp->elts[pc + 1].symbol);
|
||
|
||
if (sym_class == LOC_CONST
|
||
|| sym_class == LOC_CONST_BYTES
|
||
|| sym_class == LOC_REGISTER
|
||
|| sym_class == LOC_REGPARM)
|
||
error ("Attempt to take address of register or constant.");
|
||
|
||
return
|
||
value_zero (type, not_lval);
|
||
}
|
||
else
|
||
return locate_var_value (exp->elts[pc + 1].symbol, (CORE_ADDR) 0);
|
||
|
||
default:
|
||
if (noside == EVAL_AVOID_SIDE_EFFECTS)
|
||
{
|
||
value x = evaluate_subexp (0, exp, pos, noside);
|
||
if (VALUE_LVAL (x) == lval_memory)
|
||
return value_zero (TYPE_POINTER_TYPE (VALUE_TYPE (x)),
|
||
not_lval);
|
||
else
|
||
error ("Attempt to take address of non-lval");
|
||
}
|
||
return value_addr (evaluate_subexp (0, exp, pos, noside));
|
||
}
|
||
}
|
||
|
||
/* Evaluate like `evaluate_subexp' except coercing arrays to pointers.
|
||
When used in contexts where arrays will be coerced anyway,
|
||
this is equivalent to `evaluate_subexp'
|
||
but much faster because it avoids actually fetching array contents. */
|
||
|
||
static value
|
||
evaluate_subexp_with_coercion (exp, pos, noside)
|
||
register struct expression *exp;
|
||
register int *pos;
|
||
enum noside noside;
|
||
{
|
||
register enum exp_opcode op;
|
||
register int pc;
|
||
register value val;
|
||
|
||
pc = (*pos);
|
||
op = exp->elts[pc].opcode;
|
||
|
||
switch (op)
|
||
{
|
||
case OP_VAR_VALUE:
|
||
if (TYPE_CODE (SYMBOL_TYPE (exp->elts[pc + 1].symbol)) == TYPE_CODE_ARRAY)
|
||
{
|
||
(*pos) += 3;
|
||
val = locate_var_value (exp->elts[pc + 1].symbol, (CORE_ADDR) 0);
|
||
return value_cast (lookup_pointer_type (TYPE_TARGET_TYPE (SYMBOL_TYPE (exp->elts[pc + 1].symbol))),
|
||
val);
|
||
}
|
||
}
|
||
|
||
return evaluate_subexp (0, exp, pos, noside);
|
||
}
|
||
|
||
/* Evaluate a subexpression of EXP, at index *POS,
|
||
and return a value for the size of that subexpression.
|
||
Advance *POS over the subexpression. */
|
||
|
||
static value
|
||
evaluate_subexp_for_sizeof (exp, pos)
|
||
register struct expression *exp;
|
||
register int *pos;
|
||
{
|
||
enum exp_opcode op;
|
||
register int pc;
|
||
value val;
|
||
|
||
pc = (*pos);
|
||
op = exp->elts[pc].opcode;
|
||
|
||
switch (op)
|
||
{
|
||
/* This case is handled specially
|
||
so that we avoid creating a value for the result type.
|
||
If the result type is very big, it's desirable not to
|
||
create a value unnecessarily. */
|
||
case UNOP_IND:
|
||
(*pos)++;
|
||
val = evaluate_subexp (0, exp, pos, EVAL_AVOID_SIDE_EFFECTS);
|
||
return value_from_long (builtin_type_int, (LONGEST)
|
||
TYPE_LENGTH (TYPE_TARGET_TYPE (VALUE_TYPE (val))));
|
||
|
||
case UNOP_MEMVAL:
|
||
(*pos) += 3;
|
||
return value_from_long (builtin_type_int,
|
||
(LONGEST) TYPE_LENGTH (exp->elts[pc + 1].type));
|
||
|
||
case OP_VAR_VALUE:
|
||
(*pos) += 3;
|
||
return value_from_long (builtin_type_int,
|
||
(LONGEST) TYPE_LENGTH (SYMBOL_TYPE (exp->elts[pc + 1].symbol)));
|
||
|
||
default:
|
||
val = evaluate_subexp (0, exp, pos, EVAL_AVOID_SIDE_EFFECTS);
|
||
return value_from_long (builtin_type_int,
|
||
(LONGEST) TYPE_LENGTH (VALUE_TYPE (val)));
|
||
}
|
||
}
|