4.4BSD/usr/src/contrib/gdb-4.7.lbl/gdb/valarith.c
/* Perform arithmetic and other operations on values, for GDB.
Copyright 1986, 1989, 1991, 1992 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "defs.h"
#include "value.h"
#include "symtab.h"
#include "gdbtypes.h"
#include "expression.h"
#include "target.h"
#include <string.h>
static value
value_subscripted_rvalue PARAMS ((value, value));
value
value_add (arg1, arg2)
value arg1, arg2;
{
register value valint, valptr;
register int len;
COERCE_ARRAY (arg1);
COERCE_ARRAY (arg2);
if ((TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_PTR
|| TYPE_CODE (VALUE_TYPE (arg2)) == TYPE_CODE_PTR)
&&
(TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_INT
|| TYPE_CODE (VALUE_TYPE (arg2)) == TYPE_CODE_INT))
/* Exactly one argument is a pointer, and one is an integer. */
{
if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_PTR)
{
valptr = arg1;
valint = arg2;
}
else
{
valptr = arg2;
valint = arg1;
}
len = TYPE_LENGTH (TYPE_TARGET_TYPE (VALUE_TYPE (valptr)));
if (len == 0) len = 1; /* For (void *) */
return value_from_longest (VALUE_TYPE (valptr),
value_as_long (valptr)
+ (len * value_as_long (valint)));
}
return value_binop (arg1, arg2, BINOP_ADD);
}
value
value_sub (arg1, arg2)
value arg1, arg2;
{
COERCE_ARRAY (arg1);
COERCE_ARRAY (arg2);
if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_PTR)
{
if (TYPE_CODE (VALUE_TYPE (arg2)) == TYPE_CODE_INT)
{
/* pointer - integer. */
return value_from_longest
(VALUE_TYPE (arg1),
value_as_long (arg1)
- (TYPE_LENGTH (TYPE_TARGET_TYPE (VALUE_TYPE (arg1)))
* value_as_long (arg2)));
}
else if (VALUE_TYPE (arg1) == VALUE_TYPE (arg2))
{
/* pointer to <type x> - pointer to <type x>. */
return value_from_longest
(builtin_type_long, /* FIXME -- should be ptrdiff_t */
(value_as_long (arg1) - value_as_long (arg2))
/ TYPE_LENGTH (TYPE_TARGET_TYPE (VALUE_TYPE (arg1))));
}
else
{
error ("\
First argument of `-' is a pointer and second argument is neither\n\
an integer nor a pointer of the same type.");
}
}
return value_binop (arg1, arg2, BINOP_SUB);
}
/* Return the value of ARRAY[IDX]. */
value
value_subscript (array, idx)
value array, idx;
{
if (TYPE_CODE (VALUE_TYPE (array)) == TYPE_CODE_ARRAY
&& VALUE_LVAL (array) != lval_memory)
return value_subscripted_rvalue (array, idx);
else
return value_ind (value_add (array, idx));
}
/* Return the value of EXPR[IDX], expr an aggregate rvalue
(eg, a vector register). This routine used to promote floats
to doubles, but no longer does. */
static value
value_subscripted_rvalue (array, idx)
value array, idx;
{
struct type *elt_type = TYPE_TARGET_TYPE (VALUE_TYPE (array));
int elt_size = TYPE_LENGTH (elt_type);
int elt_offs = elt_size * longest_to_int (value_as_long (idx));
value v;
if (elt_offs >= TYPE_LENGTH (VALUE_TYPE (array)))
error ("no such vector element");
v = allocate_value (elt_type);
memcpy (VALUE_CONTENTS (v), VALUE_CONTENTS (array) + elt_offs, elt_size);
if (VALUE_LVAL (array) == lval_internalvar)
VALUE_LVAL (v) = lval_internalvar_component;
else
VALUE_LVAL (v) = not_lval;
VALUE_ADDRESS (v) = VALUE_ADDRESS (array);
VALUE_OFFSET (v) = VALUE_OFFSET (array) + elt_offs;
VALUE_BITSIZE (v) = elt_size * 8;
return v;
}
/* Check to see if either argument is a structure. This is called so
we know whether to go ahead with the normal binop or look for a
user defined function instead.
For now, we do not overload the `=' operator. */
int
binop_user_defined_p (op, arg1, arg2)
enum exp_opcode op;
value arg1, arg2;
{
if (op == BINOP_ASSIGN)
return 0;
return (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_STRUCT
|| TYPE_CODE (VALUE_TYPE (arg2)) == TYPE_CODE_STRUCT
|| (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_REF
&& TYPE_CODE (TYPE_TARGET_TYPE (VALUE_TYPE (arg1))) == TYPE_CODE_STRUCT)
|| (TYPE_CODE (VALUE_TYPE (arg2)) == TYPE_CODE_REF
&& TYPE_CODE (TYPE_TARGET_TYPE (VALUE_TYPE (arg2))) == TYPE_CODE_STRUCT));
}
/* Check to see if argument is a structure. This is called so
we know whether to go ahead with the normal unop or look for a
user defined function instead.
For now, we do not overload the `&' operator. */
int unop_user_defined_p (op, arg1)
enum exp_opcode op;
value arg1;
{
if (op == UNOP_ADDR)
return 0;
return (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_STRUCT
|| (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_REF
&& TYPE_CODE (TYPE_TARGET_TYPE (VALUE_TYPE (arg1))) == TYPE_CODE_STRUCT));
}
/* We know either arg1 or arg2 is a structure, so try to find the right
user defined function. Create an argument vector that calls
arg1.operator @ (arg1,arg2) and return that value (where '@' is any
binary operator which is legal for GNU C++).
OP is the operatore, and if it is BINOP_ASSIGN_MODIFY, then OTHEROP
is the opcode saying how to modify it. Otherwise, OTHEROP is
unused. */
value
value_x_binop (arg1, arg2, op, otherop)
value arg1, arg2;
enum exp_opcode op, otherop;
{
value * argvec;
char *ptr;
char tstr[13];
int static_memfuncp;
COERCE_REF (arg1);
COERCE_REF (arg2);
COERCE_ENUM (arg1);
COERCE_ENUM (arg2);
/* now we know that what we have to do is construct our
arg vector and find the right function to call it with. */
if (TYPE_CODE (VALUE_TYPE (arg1)) != TYPE_CODE_STRUCT)
error ("Can't do that binary op on that type"); /* FIXME be explicit */
argvec = (value *) alloca (sizeof (value) * 4);
argvec[1] = value_addr (arg1);
argvec[2] = arg2;
argvec[3] = 0;
/* make the right function name up */
strcpy(tstr, "operator__");
ptr = tstr+8;
switch (op)
{
case BINOP_ADD: strcpy(ptr,"+"); break;
case BINOP_SUB: strcpy(ptr,"-"); break;
case BINOP_MUL: strcpy(ptr,"*"); break;
case BINOP_DIV: strcpy(ptr,"/"); break;
case BINOP_REM: strcpy(ptr,"%"); break;
case BINOP_LSH: strcpy(ptr,"<<"); break;
case BINOP_RSH: strcpy(ptr,">>"); break;
case BINOP_LOGAND: strcpy(ptr,"&"); break;
case BINOP_LOGIOR: strcpy(ptr,"|"); break;
case BINOP_LOGXOR: strcpy(ptr,"^"); break;
case BINOP_AND: strcpy(ptr,"&&"); break;
case BINOP_OR: strcpy(ptr,"||"); break;
case BINOP_MIN: strcpy(ptr,"<?"); break;
case BINOP_MAX: strcpy(ptr,">?"); break;
case BINOP_ASSIGN: strcpy(ptr,"="); break;
case BINOP_ASSIGN_MODIFY:
switch (otherop)
{
case BINOP_ADD: strcpy(ptr,"+="); break;
case BINOP_SUB: strcpy(ptr,"-="); break;
case BINOP_MUL: strcpy(ptr,"*="); break;
case BINOP_DIV: strcpy(ptr,"/="); break;
case BINOP_REM: strcpy(ptr,"%="); break;
case BINOP_LOGAND: strcpy(ptr,"&="); break;
case BINOP_LOGIOR: strcpy(ptr,"|="); break;
case BINOP_LOGXOR: strcpy(ptr,"^="); break;
default:
error ("Invalid binary operation specified.");
}
break;
case BINOP_SUBSCRIPT: strcpy(ptr,"[]"); break;
case BINOP_EQUAL: strcpy(ptr,"=="); break;
case BINOP_NOTEQUAL: strcpy(ptr,"!="); break;
case BINOP_LESS: strcpy(ptr,"<"); break;
case BINOP_GTR: strcpy(ptr,">"); break;
case BINOP_GEQ: strcpy(ptr,">="); break;
case BINOP_LEQ: strcpy(ptr,"<="); break;
default:
error ("Invalid binary operation specified.");
}
argvec[0] = value_struct_elt (&arg1, argvec+1, tstr, &static_memfuncp, "structure");
if (argvec[0])
{
if (static_memfuncp)
{
argvec[1] = argvec[0];
argvec++;
}
return call_function_by_hand (argvec[0], 2 - static_memfuncp, argvec + 1);
}
error ("member function %s not found", tstr);
#ifdef lint
return call_function_by_hand (argvec[0], 2 - static_memfuncp, argvec + 1);
#endif
}
/* We know that arg1 is a structure, so try to find a unary user
defined operator that matches the operator in question.
Create an argument vector that calls arg1.operator @ (arg1)
and return that value (where '@' is (almost) any unary operator which
is legal for GNU C++). */
value
value_x_unop (arg1, op)
value arg1;
enum exp_opcode op;
{
value * argvec;
char *ptr;
char tstr[13];
int static_memfuncp;
COERCE_ENUM (arg1);
/* now we know that what we have to do is construct our
arg vector and find the right function to call it with. */
if (TYPE_CODE (VALUE_TYPE (arg1)) != TYPE_CODE_STRUCT)
error ("Can't do that unary op on that type"); /* FIXME be explicit */
argvec = (value *) alloca (sizeof (value) * 3);
argvec[1] = value_addr (arg1);
argvec[2] = 0;
/* make the right function name up */
strcpy(tstr,"operator__");
ptr = tstr+8;
switch (op)
{
case UNOP_PREINCREMENT: strcpy(ptr,"++"); break;
case UNOP_PREDECREMENT: strcpy(ptr,"++"); break;
case UNOP_POSTINCREMENT: strcpy(ptr,"++"); break;
case UNOP_POSTDECREMENT: strcpy(ptr,"++"); break;
case UNOP_ZEROP: strcpy(ptr,"!"); break;
case UNOP_LOGNOT: strcpy(ptr,"~"); break;
case UNOP_NEG: strcpy(ptr,"-"); break;
default:
error ("Invalid binary operation specified.");
}
argvec[0] = value_struct_elt (&arg1, argvec+1, tstr, &static_memfuncp, "structure");
if (argvec[0])
{
if (static_memfuncp)
{
argvec[1] = argvec[0];
argvec++;
}
return call_function_by_hand (argvec[0], 1 - static_memfuncp, argvec + 1);
}
error ("member function %s not found", tstr);
return 0; /* For lint -- never reached */
}
/* Perform a binary operation on two integers or two floats.
Does not support addition and subtraction on pointers;
use value_add or value_sub if you want to handle those possibilities. */
value
value_binop (arg1, arg2, op)
value arg1, arg2;
enum exp_opcode op;
{
register value val;
COERCE_ENUM (arg1);
COERCE_ENUM (arg2);
if ((TYPE_CODE (VALUE_TYPE (arg1)) != TYPE_CODE_FLT
&&
TYPE_CODE (VALUE_TYPE (arg1)) != TYPE_CODE_INT)
||
(TYPE_CODE (VALUE_TYPE (arg2)) != TYPE_CODE_FLT
&&
TYPE_CODE (VALUE_TYPE (arg2)) != TYPE_CODE_INT))
error ("Argument to arithmetic operation not a number.");
if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_FLT
||
TYPE_CODE (VALUE_TYPE (arg2)) == TYPE_CODE_FLT)
{
double v1, v2, v;
v1 = value_as_double (arg1);
v2 = value_as_double (arg2);
switch (op)
{
case BINOP_ADD:
v = v1 + v2;
break;
case BINOP_SUB:
v = v1 - v2;
break;
case BINOP_MUL:
v = v1 * v2;
break;
case BINOP_DIV:
v = v1 / v2;
break;
default:
error ("Integer-only operation on floating point number.");
}
val = allocate_value (builtin_type_double);
SWAP_TARGET_AND_HOST (&v, sizeof (v));
*(double *) VALUE_CONTENTS_RAW (val) = v;
}
else
/* Integral operations here. */
{
/* Should we promote to unsigned longest? */
if ((TYPE_UNSIGNED (VALUE_TYPE (arg1))
|| TYPE_UNSIGNED (VALUE_TYPE (arg2)))
&& (TYPE_LENGTH (VALUE_TYPE (arg1)) >= sizeof (unsigned LONGEST)
|| TYPE_LENGTH (VALUE_TYPE (arg2)) >= sizeof (unsigned LONGEST)))
{
unsigned LONGEST v1, v2, v;
v1 = (unsigned LONGEST) value_as_long (arg1);
v2 = (unsigned LONGEST) value_as_long (arg2);
switch (op)
{
case BINOP_ADD:
v = v1 + v2;
break;
case BINOP_SUB:
v = v1 - v2;
break;
case BINOP_MUL:
v = v1 * v2;
break;
case BINOP_DIV:
v = v1 / v2;
break;
case BINOP_REM:
v = v1 % v2;
break;
case BINOP_LSH:
v = v1 << v2;
break;
case BINOP_RSH:
v = v1 >> v2;
break;
case BINOP_LOGAND:
v = v1 & v2;
break;
case BINOP_LOGIOR:
v = v1 | v2;
break;
case BINOP_LOGXOR:
v = v1 ^ v2;
break;
case BINOP_AND:
v = v1 && v2;
break;
case BINOP_OR:
v = v1 || v2;
break;
case BINOP_MIN:
v = v1 < v2 ? v1 : v2;
break;
case BINOP_MAX:
v = v1 > v2 ? v1 : v2;
break;
default:
error ("Invalid binary operation on numbers.");
}
val = allocate_value (BUILTIN_TYPE_UNSIGNED_LONGEST);
SWAP_TARGET_AND_HOST (&v, sizeof (v));
*(unsigned LONGEST *) VALUE_CONTENTS_RAW (val) = v;
}
else
{
LONGEST v1, v2, v;
v1 = value_as_long (arg1);
v2 = value_as_long (arg2);
switch (op)
{
case BINOP_ADD:
v = v1 + v2;
break;
case BINOP_SUB:
v = v1 - v2;
break;
case BINOP_MUL:
v = v1 * v2;
break;
case BINOP_DIV:
v = v1 / v2;
break;
case BINOP_REM:
v = v1 % v2;
break;
case BINOP_LSH:
v = v1 << v2;
break;
case BINOP_RSH:
v = v1 >> v2;
break;
case BINOP_LOGAND:
v = v1 & v2;
break;
case BINOP_LOGIOR:
v = v1 | v2;
break;
case BINOP_LOGXOR:
v = v1 ^ v2;
break;
case BINOP_AND:
v = v1 && v2;
break;
case BINOP_OR:
v = v1 || v2;
break;
case BINOP_MIN:
v = v1 < v2 ? v1 : v2;
break;
case BINOP_MAX:
v = v1 > v2 ? v1 : v2;
break;
default:
error ("Invalid binary operation on numbers.");
}
val = allocate_value (BUILTIN_TYPE_LONGEST);
SWAP_TARGET_AND_HOST (&v, sizeof (v));
*(LONGEST *) VALUE_CONTENTS_RAW (val) = v;
}
}
return val;
}
/* Simulate the C operator ! -- return 1 if ARG1 contains zero. */
int
value_zerop (arg1)
value arg1;
{
register int len;
register char *p;
COERCE_ARRAY (arg1);
if (TYPE_CODE (VALUE_TYPE (arg1)) == TYPE_CODE_FLT)
return 0 == value_as_double (arg1);
len = TYPE_LENGTH (VALUE_TYPE (arg1));
p = VALUE_CONTENTS (arg1);
while (--len >= 0)
{
if (*p++)
break;
}
return len < 0;
}
/* Simulate the C operator == by returning a 1
iff ARG1 and ARG2 have equal contents. */
int
value_equal (arg1, arg2)
register value arg1, arg2;
{
register int len;
register char *p1, *p2;
enum type_code code1;
enum type_code code2;
COERCE_ARRAY (arg1);
COERCE_ARRAY (arg2);
code1 = TYPE_CODE (VALUE_TYPE (arg1));
code2 = TYPE_CODE (VALUE_TYPE (arg2));
if (code1 == TYPE_CODE_INT && code2 == TYPE_CODE_INT)
return value_as_long (arg1) == value_as_long (arg2);
else if ((code1 == TYPE_CODE_FLT || code1 == TYPE_CODE_INT)
&& (code2 == TYPE_CODE_FLT || code2 == TYPE_CODE_INT))
return value_as_double (arg1) == value_as_double (arg2);
/* FIXME: Need to promote to either CORE_ADDR or LONGEST, whichever
is bigger. */
else if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_INT)
return value_as_pointer (arg1) == (CORE_ADDR) value_as_long (arg2);
else if (code2 == TYPE_CODE_PTR && code1 == TYPE_CODE_INT)
return (CORE_ADDR) value_as_long (arg1) == value_as_pointer (arg2);
else if (code1 == code2
&& ((len = TYPE_LENGTH (VALUE_TYPE (arg1)))
== TYPE_LENGTH (VALUE_TYPE (arg2))))
{
p1 = VALUE_CONTENTS (arg1);
p2 = VALUE_CONTENTS (arg2);
while (--len >= 0)
{
if (*p1++ != *p2++)
break;
}
return len < 0;
}
else
{
error ("Invalid type combination in equality test.");
return 0; /* For lint -- never reached */
}
}
/* Simulate the C operator < by returning 1
iff ARG1's contents are less than ARG2's. */
int
value_less (arg1, arg2)
register value arg1, arg2;
{
register enum type_code code1;
register enum type_code code2;
COERCE_ARRAY (arg1);
COERCE_ARRAY (arg2);
code1 = TYPE_CODE (VALUE_TYPE (arg1));
code2 = TYPE_CODE (VALUE_TYPE (arg2));
if (code1 == TYPE_CODE_INT && code2 == TYPE_CODE_INT)
{
if (TYPE_UNSIGNED (VALUE_TYPE (arg1))
|| TYPE_UNSIGNED (VALUE_TYPE (arg2)))
return ((unsigned LONGEST) value_as_long (arg1)
< (unsigned LONGEST) value_as_long (arg2));
else
return value_as_long (arg1) < value_as_long (arg2);
}
else if ((code1 == TYPE_CODE_FLT || code1 == TYPE_CODE_INT)
&& (code2 == TYPE_CODE_FLT || code2 == TYPE_CODE_INT))
return value_as_double (arg1) < value_as_double (arg2);
else if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_PTR)
return value_as_pointer (arg1) < value_as_pointer (arg2);
/* FIXME: Need to promote to either CORE_ADDR or LONGEST, whichever
is bigger. */
else if (code1 == TYPE_CODE_PTR && code2 == TYPE_CODE_INT)
return value_as_pointer (arg1) < (CORE_ADDR) value_as_long (arg2);
else if (code2 == TYPE_CODE_PTR && code1 == TYPE_CODE_INT)
return (CORE_ADDR) value_as_long (arg1) < value_as_pointer (arg2);
else
{
error ("Invalid type combination in ordering comparison.");
return 0;
}
}
/* The unary operators - and ~. Both free the argument ARG1. */
value
value_neg (arg1)
register value arg1;
{
register struct type *type;
COERCE_ENUM (arg1);
type = VALUE_TYPE (arg1);
if (TYPE_CODE (type) == TYPE_CODE_FLT)
return value_from_double (type, - value_as_double (arg1));
else if (TYPE_CODE (type) == TYPE_CODE_INT)
return value_from_longest (type, - value_as_long (arg1));
else {
error ("Argument to negate operation not a number.");
return 0; /* For lint -- never reached */
}
}
value
value_lognot (arg1)
register value arg1;
{
COERCE_ENUM (arg1);
if (TYPE_CODE (VALUE_TYPE (arg1)) != TYPE_CODE_INT)
error ("Argument to complement operation not an integer.");
return value_from_longest (VALUE_TYPE (arg1), ~ value_as_long (arg1));
}