mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-11-23 18:14:13 +08:00
0561a208f8
* expr.c (expr): Change first parameter to int. * config/obj-coff.c: Add declarations for static functions. (coff_frob_symbol): Use SYM_AUXENT. * config/tc-i386.h (flag_16bit_code): Don't declare.
1889 lines
49 KiB
C
1889 lines
49 KiB
C
/* expr.c -operands, expressions-
|
||
Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 96, 97, 98, 1999
|
||
Free Software Foundation, Inc.
|
||
|
||
This file is part of GAS, the GNU Assembler.
|
||
|
||
GAS 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, or (at your option)
|
||
any later version.
|
||
|
||
GAS 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 GAS; see the file COPYING. If not, write to the Free
|
||
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
|
||
02111-1307, USA. */
|
||
|
||
/*
|
||
* This is really a branch office of as-read.c. I split it out to clearly
|
||
* distinguish the world of expressions from the world of statements.
|
||
* (It also gives smaller files to re-compile.)
|
||
* Here, "operand"s are of expressions, not instructions.
|
||
*/
|
||
|
||
#include <ctype.h>
|
||
#include <string.h>
|
||
#define min(a, b) ((a) < (b) ? (a) : (b))
|
||
|
||
#include "as.h"
|
||
#include "obstack.h"
|
||
|
||
static void floating_constant PARAMS ((expressionS * expressionP));
|
||
static valueT generic_bignum_to_int32 PARAMS ((void));
|
||
#ifdef BFD64
|
||
static valueT generic_bignum_to_int64 PARAMS ((void));
|
||
#endif
|
||
static void integer_constant PARAMS ((int radix, expressionS * expressionP));
|
||
static void mri_char_constant PARAMS ((expressionS *));
|
||
static void current_location PARAMS ((expressionS *));
|
||
static void clean_up_expression PARAMS ((expressionS * expressionP));
|
||
static segT operand PARAMS ((expressionS *));
|
||
static operatorT operator PARAMS ((void));
|
||
|
||
extern const char EXP_CHARS[], FLT_CHARS[];
|
||
|
||
/* We keep a mapping of expression symbols to file positions, so that
|
||
we can provide better error messages. */
|
||
|
||
struct expr_symbol_line
|
||
{
|
||
struct expr_symbol_line *next;
|
||
symbolS *sym;
|
||
char *file;
|
||
unsigned int line;
|
||
};
|
||
|
||
static struct expr_symbol_line *expr_symbol_lines;
|
||
|
||
/* Build a dummy symbol to hold a complex expression. This is how we
|
||
build expressions up out of other expressions. The symbol is put
|
||
into the fake section expr_section. */
|
||
|
||
symbolS *
|
||
make_expr_symbol (expressionP)
|
||
expressionS *expressionP;
|
||
{
|
||
expressionS zero;
|
||
const char *fake;
|
||
symbolS *symbolP;
|
||
struct expr_symbol_line *n;
|
||
|
||
if (expressionP->X_op == O_symbol
|
||
&& expressionP->X_add_number == 0)
|
||
return expressionP->X_add_symbol;
|
||
|
||
if (expressionP->X_op == O_big)
|
||
{
|
||
/* This won't work, because the actual value is stored in
|
||
generic_floating_point_number or generic_bignum, and we are
|
||
going to lose it if we haven't already. */
|
||
if (expressionP->X_add_number > 0)
|
||
as_bad (_("bignum invalid; zero assumed"));
|
||
else
|
||
as_bad (_("floating point number invalid; zero assumed"));
|
||
zero.X_op = O_constant;
|
||
zero.X_add_number = 0;
|
||
zero.X_unsigned = 0;
|
||
clean_up_expression (&zero);
|
||
expressionP = &zero;
|
||
}
|
||
|
||
fake = FAKE_LABEL_NAME;
|
||
|
||
/* Putting constant symbols in absolute_section rather than
|
||
expr_section is convenient for the old a.out code, for which
|
||
S_GET_SEGMENT does not always retrieve the value put in by
|
||
S_SET_SEGMENT. */
|
||
symbolP = symbol_create (fake,
|
||
(expressionP->X_op == O_constant
|
||
? absolute_section
|
||
: expr_section),
|
||
0, &zero_address_frag);
|
||
symbol_set_value_expression (symbolP, expressionP);
|
||
|
||
if (expressionP->X_op == O_constant)
|
||
resolve_symbol_value (symbolP, 1);
|
||
|
||
n = (struct expr_symbol_line *) xmalloc (sizeof *n);
|
||
n->sym = symbolP;
|
||
as_where (&n->file, &n->line);
|
||
n->next = expr_symbol_lines;
|
||
expr_symbol_lines = n;
|
||
|
||
return symbolP;
|
||
}
|
||
|
||
/* Return the file and line number for an expr symbol. Return
|
||
non-zero if something was found, 0 if no information is known for
|
||
the symbol. */
|
||
|
||
int
|
||
expr_symbol_where (sym, pfile, pline)
|
||
symbolS *sym;
|
||
char **pfile;
|
||
unsigned int *pline;
|
||
{
|
||
register struct expr_symbol_line *l;
|
||
|
||
for (l = expr_symbol_lines; l != NULL; l = l->next)
|
||
{
|
||
if (l->sym == sym)
|
||
{
|
||
*pfile = l->file;
|
||
*pline = l->line;
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Utilities for building expressions.
|
||
Since complex expressions are recorded as symbols for use in other
|
||
expressions these return a symbolS * and not an expressionS *.
|
||
These explicitly do not take an "add_number" argument. */
|
||
/* ??? For completeness' sake one might want expr_build_symbol.
|
||
It would just return its argument. */
|
||
|
||
/* Build an expression for an unsigned constant.
|
||
The corresponding one for signed constants is missing because
|
||
there's currently no need for it. One could add an unsigned_p flag
|
||
but that seems more clumsy. */
|
||
|
||
symbolS *
|
||
expr_build_uconstant (value)
|
||
offsetT value;
|
||
{
|
||
expressionS e;
|
||
|
||
e.X_op = O_constant;
|
||
e.X_add_number = value;
|
||
e.X_unsigned = 1;
|
||
return make_expr_symbol (&e);
|
||
}
|
||
|
||
/* Build an expression for OP s1. */
|
||
|
||
symbolS *
|
||
expr_build_unary (op, s1)
|
||
operatorT op;
|
||
symbolS *s1;
|
||
{
|
||
expressionS e;
|
||
|
||
e.X_op = op;
|
||
e.X_add_symbol = s1;
|
||
e.X_add_number = 0;
|
||
return make_expr_symbol (&e);
|
||
}
|
||
|
||
/* Build an expression for s1 OP s2. */
|
||
|
||
symbolS *
|
||
expr_build_binary (op, s1, s2)
|
||
operatorT op;
|
||
symbolS *s1;
|
||
symbolS *s2;
|
||
{
|
||
expressionS e;
|
||
|
||
e.X_op = op;
|
||
e.X_add_symbol = s1;
|
||
e.X_op_symbol = s2;
|
||
e.X_add_number = 0;
|
||
return make_expr_symbol (&e);
|
||
}
|
||
|
||
/* Build an expression for the current location ('.'). */
|
||
|
||
symbolS *
|
||
expr_build_dot ()
|
||
{
|
||
expressionS e;
|
||
|
||
current_location (&e);
|
||
return make_expr_symbol (&e);
|
||
}
|
||
|
||
/*
|
||
* Build any floating-point literal here.
|
||
* Also build any bignum literal here.
|
||
*/
|
||
|
||
/* Seems atof_machine can backscan through generic_bignum and hit whatever
|
||
happens to be loaded before it in memory. And its way too complicated
|
||
for me to fix right. Thus a hack. JF: Just make generic_bignum bigger,
|
||
and never write into the early words, thus they'll always be zero.
|
||
I hate Dean's floating-point code. Bleh. */
|
||
LITTLENUM_TYPE generic_bignum[SIZE_OF_LARGE_NUMBER + 6];
|
||
FLONUM_TYPE generic_floating_point_number =
|
||
{
|
||
&generic_bignum[6], /* low (JF: Was 0) */
|
||
&generic_bignum[SIZE_OF_LARGE_NUMBER + 6 - 1], /* high JF: (added +6) */
|
||
0, /* leader */
|
||
0, /* exponent */
|
||
0 /* sign */
|
||
};
|
||
/* If nonzero, we've been asked to assemble nan, +inf or -inf */
|
||
int generic_floating_point_magic;
|
||
|
||
static void
|
||
floating_constant (expressionP)
|
||
expressionS *expressionP;
|
||
{
|
||
/* input_line_pointer->*/
|
||
/* floating-point constant. */
|
||
int error_code;
|
||
|
||
error_code = atof_generic (&input_line_pointer, ".", EXP_CHARS,
|
||
&generic_floating_point_number);
|
||
|
||
if (error_code)
|
||
{
|
||
if (error_code == ERROR_EXPONENT_OVERFLOW)
|
||
{
|
||
as_bad (_("bad floating-point constant: exponent overflow, probably assembling junk"));
|
||
}
|
||
else
|
||
{
|
||
as_bad (_("bad floating-point constant: unknown error code=%d."), error_code);
|
||
}
|
||
}
|
||
expressionP->X_op = O_big;
|
||
/* input_line_pointer->just after constant, */
|
||
/* which may point to whitespace. */
|
||
expressionP->X_add_number = -1;
|
||
}
|
||
|
||
static valueT
|
||
generic_bignum_to_int32 ()
|
||
{
|
||
valueT number =
|
||
((generic_bignum[1] & LITTLENUM_MASK) << LITTLENUM_NUMBER_OF_BITS)
|
||
| (generic_bignum[0] & LITTLENUM_MASK);
|
||
number &= 0xffffffff;
|
||
return number;
|
||
}
|
||
|
||
#ifdef BFD64
|
||
static valueT
|
||
generic_bignum_to_int64 ()
|
||
{
|
||
valueT number =
|
||
((((((((valueT) generic_bignum[3] & LITTLENUM_MASK)
|
||
<< LITTLENUM_NUMBER_OF_BITS)
|
||
| ((valueT) generic_bignum[2] & LITTLENUM_MASK))
|
||
<< LITTLENUM_NUMBER_OF_BITS)
|
||
| ((valueT) generic_bignum[1] & LITTLENUM_MASK))
|
||
<< LITTLENUM_NUMBER_OF_BITS)
|
||
| ((valueT) generic_bignum[0] & LITTLENUM_MASK));
|
||
return number;
|
||
}
|
||
#endif
|
||
|
||
static void
|
||
integer_constant (radix, expressionP)
|
||
int radix;
|
||
expressionS *expressionP;
|
||
{
|
||
char *start; /* start of number. */
|
||
char *suffix = NULL;
|
||
char c;
|
||
valueT number; /* offset or (absolute) value */
|
||
short int digit; /* value of next digit in current radix */
|
||
short int maxdig = 0;/* highest permitted digit value. */
|
||
int too_many_digits = 0; /* if we see >= this number of */
|
||
char *name; /* points to name of symbol */
|
||
symbolS *symbolP; /* points to symbol */
|
||
|
||
int small; /* true if fits in 32 bits. */
|
||
|
||
/* May be bignum, or may fit in 32 bits. */
|
||
/* Most numbers fit into 32 bits, and we want this case to be fast.
|
||
so we pretend it will fit into 32 bits. If, after making up a 32
|
||
bit number, we realise that we have scanned more digits than
|
||
comfortably fit into 32 bits, we re-scan the digits coding them
|
||
into a bignum. For decimal and octal numbers we are
|
||
conservative: Some numbers may be assumed bignums when in fact
|
||
they do fit into 32 bits. Numbers of any radix can have excess
|
||
leading zeros: We strive to recognise this and cast them back
|
||
into 32 bits. We must check that the bignum really is more than
|
||
32 bits, and change it back to a 32-bit number if it fits. The
|
||
number we are looking for is expected to be positive, but if it
|
||
fits into 32 bits as an unsigned number, we let it be a 32-bit
|
||
number. The cavalier approach is for speed in ordinary cases. */
|
||
/* This has been extended for 64 bits. We blindly assume that if
|
||
you're compiling in 64-bit mode, the target is a 64-bit machine.
|
||
This should be cleaned up. */
|
||
|
||
#ifdef BFD64
|
||
#define valuesize 64
|
||
#else /* includes non-bfd case, mostly */
|
||
#define valuesize 32
|
||
#endif
|
||
|
||
if (flag_m68k_mri && radix == 0)
|
||
{
|
||
int flt = 0;
|
||
|
||
/* In MRI mode, the number may have a suffix indicating the
|
||
radix. For that matter, it might actually be a floating
|
||
point constant. */
|
||
for (suffix = input_line_pointer;
|
||
isalnum ((unsigned char) *suffix);
|
||
suffix++)
|
||
{
|
||
if (*suffix == 'e' || *suffix == 'E')
|
||
flt = 1;
|
||
}
|
||
|
||
if (suffix == input_line_pointer)
|
||
{
|
||
radix = 10;
|
||
suffix = NULL;
|
||
}
|
||
else
|
||
{
|
||
c = *--suffix;
|
||
if (islower ((unsigned char) c))
|
||
c = toupper (c);
|
||
if (c == 'B')
|
||
radix = 2;
|
||
else if (c == 'D')
|
||
radix = 10;
|
||
else if (c == 'O' || c == 'Q')
|
||
radix = 8;
|
||
else if (c == 'H')
|
||
radix = 16;
|
||
else if (suffix[1] == '.' || c == 'E' || flt)
|
||
{
|
||
floating_constant (expressionP);
|
||
return;
|
||
}
|
||
else
|
||
{
|
||
radix = 10;
|
||
suffix = NULL;
|
||
}
|
||
}
|
||
}
|
||
|
||
switch (radix)
|
||
{
|
||
case 2:
|
||
maxdig = 2;
|
||
too_many_digits = valuesize + 1;
|
||
break;
|
||
case 8:
|
||
maxdig = radix = 8;
|
||
too_many_digits = (valuesize + 2) / 3 + 1;
|
||
break;
|
||
case 16:
|
||
maxdig = radix = 16;
|
||
too_many_digits = (valuesize + 3) / 4 + 1;
|
||
break;
|
||
case 10:
|
||
maxdig = radix = 10;
|
||
too_many_digits = (valuesize + 11) / 4; /* very rough */
|
||
}
|
||
#undef valuesize
|
||
start = input_line_pointer;
|
||
c = *input_line_pointer++;
|
||
for (number = 0;
|
||
(digit = hex_value (c)) < maxdig;
|
||
c = *input_line_pointer++)
|
||
{
|
||
number = number * radix + digit;
|
||
}
|
||
/* c contains character after number. */
|
||
/* input_line_pointer->char after c. */
|
||
small = (input_line_pointer - start - 1) < too_many_digits;
|
||
|
||
if (radix == 16 && c == '_')
|
||
{
|
||
/* This is literal of the form 0x333_0_12345678_1.
|
||
This example is equivalent to 0x00000333000000001234567800000001. */
|
||
|
||
int num_little_digits = 0;
|
||
int i;
|
||
input_line_pointer = start; /*->1st digit. */
|
||
|
||
know (LITTLENUM_NUMBER_OF_BITS == 16);
|
||
|
||
for (c = '_'; c == '_'; num_little_digits+=2)
|
||
{
|
||
|
||
/* Convert one 64-bit word. */
|
||
int ndigit = 0;
|
||
number = 0;
|
||
for (c = *input_line_pointer++;
|
||
(digit = hex_value (c)) < maxdig;
|
||
c = *(input_line_pointer++))
|
||
{
|
||
number = number * radix + digit;
|
||
ndigit++;
|
||
}
|
||
|
||
/* Check for 8 digit per word max. */
|
||
if (ndigit > 8)
|
||
as_bad (_("A bignum with underscores may not have more than 8 hex digits in any word."));
|
||
|
||
/* Add this chunk to the bignum. Shift things down 2 little digits.*/
|
||
know (LITTLENUM_NUMBER_OF_BITS == 16);
|
||
for (i = min (num_little_digits + 1, SIZE_OF_LARGE_NUMBER - 1); i >= 2; i--)
|
||
generic_bignum[i] = generic_bignum[i-2];
|
||
|
||
/* Add the new digits as the least significant new ones. */
|
||
generic_bignum[0] = number & 0xffffffff;
|
||
generic_bignum[1] = number >> 16;
|
||
}
|
||
|
||
/* Again, c is char after number, input_line_pointer->after c. */
|
||
|
||
if (num_little_digits > SIZE_OF_LARGE_NUMBER - 1)
|
||
num_little_digits = SIZE_OF_LARGE_NUMBER - 1;
|
||
|
||
assert (num_little_digits >= 4);
|
||
|
||
if (num_little_digits != 8)
|
||
as_bad (_("A bignum with underscores must have exactly 4 words."));
|
||
|
||
/* We might have some leading zeros. These can be trimmed to give
|
||
* us a change to fit this constant into a small number.
|
||
*/
|
||
while (generic_bignum[num_little_digits-1] == 0 && num_little_digits > 1)
|
||
num_little_digits--;
|
||
|
||
if (num_little_digits <= 2)
|
||
{
|
||
/* will fit into 32 bits. */
|
||
number = generic_bignum_to_int32 ();
|
||
small = 1;
|
||
}
|
||
#ifdef BFD64
|
||
else if (num_little_digits <= 4)
|
||
{
|
||
/* Will fit into 64 bits. */
|
||
number = generic_bignum_to_int64 ();
|
||
small = 1;
|
||
}
|
||
#endif
|
||
else
|
||
{
|
||
small = 0;
|
||
number = num_little_digits; /* number of littlenums in the bignum. */
|
||
}
|
||
}
|
||
else if (!small)
|
||
{
|
||
/*
|
||
* we saw a lot of digits. manufacture a bignum the hard way.
|
||
*/
|
||
LITTLENUM_TYPE *leader; /*->high order littlenum of the bignum. */
|
||
LITTLENUM_TYPE *pointer; /*->littlenum we are frobbing now. */
|
||
long carry;
|
||
|
||
leader = generic_bignum;
|
||
generic_bignum[0] = 0;
|
||
generic_bignum[1] = 0;
|
||
generic_bignum[2] = 0;
|
||
generic_bignum[3] = 0;
|
||
input_line_pointer = start; /*->1st digit. */
|
||
c = *input_line_pointer++;
|
||
for (;
|
||
(carry = hex_value (c)) < maxdig;
|
||
c = *input_line_pointer++)
|
||
{
|
||
for (pointer = generic_bignum;
|
||
pointer <= leader;
|
||
pointer++)
|
||
{
|
||
long work;
|
||
|
||
work = carry + radix * *pointer;
|
||
*pointer = work & LITTLENUM_MASK;
|
||
carry = work >> LITTLENUM_NUMBER_OF_BITS;
|
||
}
|
||
if (carry)
|
||
{
|
||
if (leader < generic_bignum + SIZE_OF_LARGE_NUMBER - 1)
|
||
{
|
||
/* room to grow a longer bignum. */
|
||
*++leader = carry;
|
||
}
|
||
}
|
||
}
|
||
/* again, c is char after number, */
|
||
/* input_line_pointer->after c. */
|
||
know (LITTLENUM_NUMBER_OF_BITS == 16);
|
||
if (leader < generic_bignum + 2)
|
||
{
|
||
/* will fit into 32 bits. */
|
||
number = generic_bignum_to_int32 ();
|
||
small = 1;
|
||
}
|
||
#ifdef BFD64
|
||
else if (leader < generic_bignum + 4)
|
||
{
|
||
/* Will fit into 64 bits. */
|
||
number = generic_bignum_to_int64 ();
|
||
small = 1;
|
||
}
|
||
#endif
|
||
else
|
||
{
|
||
number = leader - generic_bignum + 1; /* number of littlenums in the bignum. */
|
||
}
|
||
}
|
||
|
||
if (flag_m68k_mri && suffix != NULL && input_line_pointer - 1 == suffix)
|
||
c = *input_line_pointer++;
|
||
|
||
if (small)
|
||
{
|
||
/*
|
||
* here with number, in correct radix. c is the next char.
|
||
* note that unlike un*x, we allow "011f" "0x9f" to
|
||
* both mean the same as the (conventional) "9f". this is simply easier
|
||
* than checking for strict canonical form. syntax sux!
|
||
*/
|
||
|
||
if (LOCAL_LABELS_FB && c == 'b')
|
||
{
|
||
/*
|
||
* backward ref to local label.
|
||
* because it is backward, expect it to be defined.
|
||
*/
|
||
/* Construct a local label. */
|
||
name = fb_label_name ((int) number, 0);
|
||
|
||
/* seen before, or symbol is defined: ok */
|
||
symbolP = symbol_find (name);
|
||
if ((symbolP != NULL) && (S_IS_DEFINED (symbolP)))
|
||
{
|
||
/* local labels are never absolute. don't waste time
|
||
checking absoluteness. */
|
||
know (SEG_NORMAL (S_GET_SEGMENT (symbolP)));
|
||
|
||
expressionP->X_op = O_symbol;
|
||
expressionP->X_add_symbol = symbolP;
|
||
}
|
||
else
|
||
{
|
||
/* either not seen or not defined. */
|
||
/* @@ Should print out the original string instead of
|
||
the parsed number. */
|
||
as_bad (_("backw. ref to unknown label \"%d:\", 0 assumed."),
|
||
(int) number);
|
||
expressionP->X_op = O_constant;
|
||
}
|
||
|
||
expressionP->X_add_number = 0;
|
||
} /* case 'b' */
|
||
else if (LOCAL_LABELS_FB && c == 'f')
|
||
{
|
||
/*
|
||
* forward reference. expect symbol to be undefined or
|
||
* unknown. undefined: seen it before. unknown: never seen
|
||
* it before.
|
||
* construct a local label name, then an undefined symbol.
|
||
* don't create a xseg frag for it: caller may do that.
|
||
* just return it as never seen before.
|
||
*/
|
||
name = fb_label_name ((int) number, 1);
|
||
symbolP = symbol_find_or_make (name);
|
||
/* we have no need to check symbol properties. */
|
||
#ifndef many_segments
|
||
/* since "know" puts its arg into a "string", we
|
||
can't have newlines in the argument. */
|
||
know (S_GET_SEGMENT (symbolP) == undefined_section || S_GET_SEGMENT (symbolP) == text_section || S_GET_SEGMENT (symbolP) == data_section);
|
||
#endif
|
||
expressionP->X_op = O_symbol;
|
||
expressionP->X_add_symbol = symbolP;
|
||
expressionP->X_add_number = 0;
|
||
} /* case 'f' */
|
||
else if (LOCAL_LABELS_DOLLAR && c == '$')
|
||
{
|
||
/* If the dollar label is *currently* defined, then this is just
|
||
another reference to it. If it is not *currently* defined,
|
||
then this is a fresh instantiation of that number, so create
|
||
it. */
|
||
|
||
if (dollar_label_defined ((long) number))
|
||
{
|
||
name = dollar_label_name ((long) number, 0);
|
||
symbolP = symbol_find (name);
|
||
know (symbolP != NULL);
|
||
}
|
||
else
|
||
{
|
||
name = dollar_label_name ((long) number, 1);
|
||
symbolP = symbol_find_or_make (name);
|
||
}
|
||
|
||
expressionP->X_op = O_symbol;
|
||
expressionP->X_add_symbol = symbolP;
|
||
expressionP->X_add_number = 0;
|
||
} /* case '$' */
|
||
else
|
||
{
|
||
expressionP->X_op = O_constant;
|
||
#ifdef TARGET_WORD_SIZE
|
||
/* Sign extend NUMBER. */
|
||
number |= (-(number >> (TARGET_WORD_SIZE - 1))) << (TARGET_WORD_SIZE - 1);
|
||
#endif
|
||
expressionP->X_add_number = number;
|
||
input_line_pointer--; /* restore following character. */
|
||
} /* really just a number */
|
||
}
|
||
else
|
||
{
|
||
/* not a small number */
|
||
expressionP->X_op = O_big;
|
||
expressionP->X_add_number = number; /* number of littlenums */
|
||
input_line_pointer--; /*->char following number. */
|
||
}
|
||
}
|
||
|
||
/* Parse an MRI multi character constant. */
|
||
|
||
static void
|
||
mri_char_constant (expressionP)
|
||
expressionS *expressionP;
|
||
{
|
||
int i;
|
||
|
||
if (*input_line_pointer == '\''
|
||
&& input_line_pointer[1] != '\'')
|
||
{
|
||
expressionP->X_op = O_constant;
|
||
expressionP->X_add_number = 0;
|
||
return;
|
||
}
|
||
|
||
/* In order to get the correct byte ordering, we must build the
|
||
number in reverse. */
|
||
for (i = SIZE_OF_LARGE_NUMBER - 1; i >= 0; i--)
|
||
{
|
||
int j;
|
||
|
||
generic_bignum[i] = 0;
|
||
for (j = 0; j < CHARS_PER_LITTLENUM; j++)
|
||
{
|
||
if (*input_line_pointer == '\'')
|
||
{
|
||
if (input_line_pointer[1] != '\'')
|
||
break;
|
||
++input_line_pointer;
|
||
}
|
||
generic_bignum[i] <<= 8;
|
||
generic_bignum[i] += *input_line_pointer;
|
||
++input_line_pointer;
|
||
}
|
||
|
||
if (i < SIZE_OF_LARGE_NUMBER - 1)
|
||
{
|
||
/* If there is more than one littlenum, left justify the
|
||
last one to make it match the earlier ones. If there is
|
||
only one, we can just use the value directly. */
|
||
for (; j < CHARS_PER_LITTLENUM; j++)
|
||
generic_bignum[i] <<= 8;
|
||
}
|
||
|
||
if (*input_line_pointer == '\''
|
||
&& input_line_pointer[1] != '\'')
|
||
break;
|
||
}
|
||
|
||
if (i < 0)
|
||
{
|
||
as_bad (_("Character constant too large"));
|
||
i = 0;
|
||
}
|
||
|
||
if (i > 0)
|
||
{
|
||
int c;
|
||
int j;
|
||
|
||
c = SIZE_OF_LARGE_NUMBER - i;
|
||
for (j = 0; j < c; j++)
|
||
generic_bignum[j] = generic_bignum[i + j];
|
||
i = c;
|
||
}
|
||
|
||
know (LITTLENUM_NUMBER_OF_BITS == 16);
|
||
if (i > 2)
|
||
{
|
||
expressionP->X_op = O_big;
|
||
expressionP->X_add_number = i;
|
||
}
|
||
else
|
||
{
|
||
expressionP->X_op = O_constant;
|
||
if (i < 2)
|
||
expressionP->X_add_number = generic_bignum[0] & LITTLENUM_MASK;
|
||
else
|
||
expressionP->X_add_number =
|
||
(((generic_bignum[1] & LITTLENUM_MASK)
|
||
<< LITTLENUM_NUMBER_OF_BITS)
|
||
| (generic_bignum[0] & LITTLENUM_MASK));
|
||
}
|
||
|
||
/* Skip the final closing quote. */
|
||
++input_line_pointer;
|
||
}
|
||
|
||
/* Return an expression representing the current location. This
|
||
handles the magic symbol `.'. */
|
||
|
||
static void
|
||
current_location (expressionp)
|
||
expressionS *expressionp;
|
||
{
|
||
if (now_seg == absolute_section)
|
||
{
|
||
expressionp->X_op = O_constant;
|
||
expressionp->X_add_number = abs_section_offset;
|
||
}
|
||
else
|
||
{
|
||
symbolS *symbolp;
|
||
|
||
symbolp = symbol_new (FAKE_LABEL_NAME, now_seg,
|
||
(valueT) frag_now_fix (),
|
||
frag_now);
|
||
expressionp->X_op = O_symbol;
|
||
expressionp->X_add_symbol = symbolp;
|
||
expressionp->X_add_number = 0;
|
||
}
|
||
}
|
||
|
||
/*
|
||
* Summary of operand().
|
||
*
|
||
* in: Input_line_pointer points to 1st char of operand, which may
|
||
* be a space.
|
||
*
|
||
* out: A expressionS.
|
||
* The operand may have been empty: in this case X_op == O_absent.
|
||
* Input_line_pointer->(next non-blank) char after operand.
|
||
*/
|
||
|
||
static segT
|
||
operand (expressionP)
|
||
expressionS *expressionP;
|
||
{
|
||
char c;
|
||
symbolS *symbolP; /* points to symbol */
|
||
char *name; /* points to name of symbol */
|
||
segT segment;
|
||
|
||
/* All integers are regarded as unsigned unless they are negated.
|
||
This is because the only thing which cares whether a number is
|
||
unsigned is the code in emit_expr which extends constants into
|
||
bignums. It should only sign extend negative numbers, so that
|
||
something like ``.quad 0x80000000'' is not sign extended even
|
||
though it appears negative if valueT is 32 bits. */
|
||
expressionP->X_unsigned = 1;
|
||
|
||
/* digits, assume it is a bignum. */
|
||
|
||
SKIP_WHITESPACE (); /* leading whitespace is part of operand. */
|
||
c = *input_line_pointer++; /* input_line_pointer->past char in c. */
|
||
|
||
switch (c)
|
||
{
|
||
case '1':
|
||
case '2':
|
||
case '3':
|
||
case '4':
|
||
case '5':
|
||
case '6':
|
||
case '7':
|
||
case '8':
|
||
case '9':
|
||
input_line_pointer--;
|
||
|
||
integer_constant (flag_m68k_mri ? 0 : 10, expressionP);
|
||
break;
|
||
|
||
case '0':
|
||
/* non-decimal radix */
|
||
|
||
if (flag_m68k_mri)
|
||
{
|
||
char *s;
|
||
|
||
/* Check for a hex constant. */
|
||
for (s = input_line_pointer; hex_p (*s); s++)
|
||
;
|
||
if (*s == 'h' || *s == 'H')
|
||
{
|
||
--input_line_pointer;
|
||
integer_constant (0, expressionP);
|
||
break;
|
||
}
|
||
}
|
||
|
||
c = *input_line_pointer;
|
||
switch (c)
|
||
{
|
||
case 'o':
|
||
case 'O':
|
||
case 'q':
|
||
case 'Q':
|
||
case '8':
|
||
case '9':
|
||
if (flag_m68k_mri)
|
||
{
|
||
integer_constant (0, expressionP);
|
||
break;
|
||
}
|
||
/* Fall through. */
|
||
default:
|
||
default_case:
|
||
if (c && strchr (FLT_CHARS, c))
|
||
{
|
||
input_line_pointer++;
|
||
floating_constant (expressionP);
|
||
expressionP->X_add_number =
|
||
- (isupper ((unsigned char) c) ? tolower (c) : c);
|
||
}
|
||
else
|
||
{
|
||
/* The string was only zero */
|
||
expressionP->X_op = O_constant;
|
||
expressionP->X_add_number = 0;
|
||
}
|
||
|
||
break;
|
||
|
||
case 'x':
|
||
case 'X':
|
||
if (flag_m68k_mri)
|
||
goto default_case;
|
||
input_line_pointer++;
|
||
integer_constant (16, expressionP);
|
||
break;
|
||
|
||
case 'b':
|
||
if (LOCAL_LABELS_FB && ! flag_m68k_mri)
|
||
{
|
||
/* This code used to check for '+' and '-' here, and, in
|
||
some conditions, fall through to call
|
||
integer_constant. However, that didn't make sense,
|
||
as integer_constant only accepts digits. */
|
||
/* Some of our code elsewhere does permit digits greater
|
||
than the expected base; for consistency, do the same
|
||
here. */
|
||
if (input_line_pointer[1] < '0'
|
||
|| input_line_pointer[1] > '9')
|
||
{
|
||
/* Parse this as a back reference to label 0. */
|
||
input_line_pointer--;
|
||
integer_constant (10, expressionP);
|
||
break;
|
||
}
|
||
/* Otherwise, parse this as a binary number. */
|
||
}
|
||
/* Fall through. */
|
||
case 'B':
|
||
input_line_pointer++;
|
||
if (flag_m68k_mri)
|
||
goto default_case;
|
||
integer_constant (2, expressionP);
|
||
break;
|
||
|
||
case '0':
|
||
case '1':
|
||
case '2':
|
||
case '3':
|
||
case '4':
|
||
case '5':
|
||
case '6':
|
||
case '7':
|
||
integer_constant (flag_m68k_mri ? 0 : 8, expressionP);
|
||
break;
|
||
|
||
case 'f':
|
||
if (LOCAL_LABELS_FB)
|
||
{
|
||
/* If it says "0f" and it could possibly be a floating point
|
||
number, make it one. Otherwise, make it a local label,
|
||
and try to deal with parsing the rest later. */
|
||
if (!input_line_pointer[1]
|
||
|| (is_end_of_line[0xff & input_line_pointer[1]]))
|
||
goto is_0f_label;
|
||
{
|
||
char *cp = input_line_pointer + 1;
|
||
int r = atof_generic (&cp, ".", EXP_CHARS,
|
||
&generic_floating_point_number);
|
||
switch (r)
|
||
{
|
||
case 0:
|
||
case ERROR_EXPONENT_OVERFLOW:
|
||
if (*cp == 'f' || *cp == 'b')
|
||
/* looks like a difference expression */
|
||
goto is_0f_label;
|
||
else if (cp == input_line_pointer + 1)
|
||
/* No characters has been accepted -- looks like
|
||
end of operand. */
|
||
goto is_0f_label;
|
||
else
|
||
goto is_0f_float;
|
||
default:
|
||
as_fatal (_("expr.c(operand): bad atof_generic return val %d"),
|
||
r);
|
||
}
|
||
}
|
||
|
||
/* Okay, now we've sorted it out. We resume at one of these
|
||
two labels, depending on what we've decided we're probably
|
||
looking at. */
|
||
is_0f_label:
|
||
input_line_pointer--;
|
||
integer_constant (10, expressionP);
|
||
break;
|
||
|
||
is_0f_float:
|
||
/* fall through */
|
||
;
|
||
}
|
||
|
||
case 'd':
|
||
case 'D':
|
||
if (flag_m68k_mri)
|
||
{
|
||
integer_constant (0, expressionP);
|
||
break;
|
||
}
|
||
/* Fall through. */
|
||
case 'F':
|
||
case 'r':
|
||
case 'e':
|
||
case 'E':
|
||
case 'g':
|
||
case 'G':
|
||
input_line_pointer++;
|
||
floating_constant (expressionP);
|
||
expressionP->X_add_number =
|
||
- (isupper ((unsigned char) c) ? tolower (c) : c);
|
||
break;
|
||
|
||
case '$':
|
||
if (LOCAL_LABELS_DOLLAR)
|
||
{
|
||
integer_constant (10, expressionP);
|
||
break;
|
||
}
|
||
else
|
||
goto default_case;
|
||
}
|
||
|
||
break;
|
||
|
||
case '(':
|
||
#ifndef NEED_INDEX_OPERATOR
|
||
case '[':
|
||
#endif
|
||
/* didn't begin with digit & not a name */
|
||
segment = expression (expressionP);
|
||
/* Expression() will pass trailing whitespace */
|
||
if ((c == '(' && *input_line_pointer++ != ')')
|
||
|| (c == '[' && *input_line_pointer++ != ']'))
|
||
{
|
||
as_bad (_("Missing ')' assumed"));
|
||
input_line_pointer--;
|
||
}
|
||
SKIP_WHITESPACE ();
|
||
/* here with input_line_pointer->char after "(...)" */
|
||
return segment;
|
||
|
||
case 'E':
|
||
if (! flag_m68k_mri || *input_line_pointer != '\'')
|
||
goto de_fault;
|
||
as_bad (_("EBCDIC constants are not supported"));
|
||
/* Fall through. */
|
||
case 'A':
|
||
if (! flag_m68k_mri || *input_line_pointer != '\'')
|
||
goto de_fault;
|
||
++input_line_pointer;
|
||
/* Fall through. */
|
||
case '\'':
|
||
if (! flag_m68k_mri)
|
||
{
|
||
/* Warning: to conform to other people's assemblers NO
|
||
ESCAPEMENT is permitted for a single quote. The next
|
||
character, parity errors and all, is taken as the value
|
||
of the operand. VERY KINKY. */
|
||
expressionP->X_op = O_constant;
|
||
expressionP->X_add_number = *input_line_pointer++;
|
||
break;
|
||
}
|
||
|
||
mri_char_constant (expressionP);
|
||
break;
|
||
|
||
case '+':
|
||
(void) operand (expressionP);
|
||
break;
|
||
|
||
case '"':
|
||
/* Double quote is the bitwise not operator in MRI mode. */
|
||
if (! flag_m68k_mri)
|
||
goto de_fault;
|
||
/* Fall through. */
|
||
case '~':
|
||
/* ~ is permitted to start a label on the Delta. */
|
||
if (is_name_beginner (c))
|
||
goto isname;
|
||
case '!':
|
||
case '-':
|
||
{
|
||
operand (expressionP);
|
||
if (expressionP->X_op == O_constant)
|
||
{
|
||
/* input_line_pointer -> char after operand */
|
||
if (c == '-')
|
||
{
|
||
expressionP->X_add_number = - expressionP->X_add_number;
|
||
/* Notice: '-' may overflow: no warning is given. This is
|
||
compatible with other people's assemblers. Sigh. */
|
||
expressionP->X_unsigned = 0;
|
||
}
|
||
else if (c == '~' || c == '"')
|
||
expressionP->X_add_number = ~ expressionP->X_add_number;
|
||
else
|
||
expressionP->X_add_number = ! expressionP->X_add_number;
|
||
}
|
||
else if (expressionP->X_op != O_illegal
|
||
&& expressionP->X_op != O_absent)
|
||
{
|
||
expressionP->X_add_symbol = make_expr_symbol (expressionP);
|
||
if (c == '-')
|
||
expressionP->X_op = O_uminus;
|
||
else if (c == '~' || c == '"')
|
||
expressionP->X_op = O_bit_not;
|
||
else
|
||
expressionP->X_op = O_logical_not;
|
||
expressionP->X_add_number = 0;
|
||
}
|
||
else
|
||
as_warn (_("Unary operator %c ignored because bad operand follows"),
|
||
c);
|
||
}
|
||
break;
|
||
|
||
case '$':
|
||
/* $ is the program counter when in MRI mode, or when DOLLAR_DOT
|
||
is defined. */
|
||
#ifndef DOLLAR_DOT
|
||
if (! flag_m68k_mri)
|
||
goto de_fault;
|
||
#endif
|
||
if (flag_m68k_mri && hex_p (*input_line_pointer))
|
||
{
|
||
/* In MRI mode, $ is also used as the prefix for a
|
||
hexadecimal constant. */
|
||
integer_constant (16, expressionP);
|
||
break;
|
||
}
|
||
|
||
if (is_part_of_name (*input_line_pointer))
|
||
goto isname;
|
||
|
||
current_location (expressionP);
|
||
break;
|
||
|
||
case '.':
|
||
if (!is_part_of_name (*input_line_pointer))
|
||
{
|
||
current_location (expressionP);
|
||
break;
|
||
}
|
||
else if ((strncasecmp (input_line_pointer, "startof.", 8) == 0
|
||
&& ! is_part_of_name (input_line_pointer[8]))
|
||
|| (strncasecmp (input_line_pointer, "sizeof.", 7) == 0
|
||
&& ! is_part_of_name (input_line_pointer[7])))
|
||
{
|
||
int start;
|
||
|
||
start = (input_line_pointer[1] == 't'
|
||
|| input_line_pointer[1] == 'T');
|
||
input_line_pointer += start ? 8 : 7;
|
||
SKIP_WHITESPACE ();
|
||
if (*input_line_pointer != '(')
|
||
as_bad (_("syntax error in .startof. or .sizeof."));
|
||
else
|
||
{
|
||
char *buf;
|
||
|
||
++input_line_pointer;
|
||
SKIP_WHITESPACE ();
|
||
name = input_line_pointer;
|
||
c = get_symbol_end ();
|
||
|
||
buf = (char *) xmalloc (strlen (name) + 10);
|
||
if (start)
|
||
sprintf (buf, ".startof.%s", name);
|
||
else
|
||
sprintf (buf, ".sizeof.%s", name);
|
||
symbolP = symbol_make (buf);
|
||
free (buf);
|
||
|
||
expressionP->X_op = O_symbol;
|
||
expressionP->X_add_symbol = symbolP;
|
||
expressionP->X_add_number = 0;
|
||
|
||
*input_line_pointer = c;
|
||
SKIP_WHITESPACE ();
|
||
if (*input_line_pointer != ')')
|
||
as_bad (_("syntax error in .startof. or .sizeof."));
|
||
else
|
||
++input_line_pointer;
|
||
}
|
||
break;
|
||
}
|
||
else
|
||
{
|
||
goto isname;
|
||
}
|
||
case ',':
|
||
case '\n':
|
||
case '\0':
|
||
eol:
|
||
/* can't imagine any other kind of operand */
|
||
expressionP->X_op = O_absent;
|
||
input_line_pointer--;
|
||
break;
|
||
|
||
case '%':
|
||
if (! flag_m68k_mri)
|
||
goto de_fault;
|
||
integer_constant (2, expressionP);
|
||
break;
|
||
|
||
case '@':
|
||
if (! flag_m68k_mri)
|
||
goto de_fault;
|
||
integer_constant (8, expressionP);
|
||
break;
|
||
|
||
case ':':
|
||
if (! flag_m68k_mri)
|
||
goto de_fault;
|
||
|
||
/* In MRI mode, this is a floating point constant represented
|
||
using hexadecimal digits. */
|
||
|
||
++input_line_pointer;
|
||
integer_constant (16, expressionP);
|
||
break;
|
||
|
||
case '*':
|
||
if (! flag_m68k_mri || is_part_of_name (*input_line_pointer))
|
||
goto de_fault;
|
||
|
||
current_location (expressionP);
|
||
break;
|
||
|
||
default:
|
||
de_fault:
|
||
if (is_end_of_line[(unsigned char) c])
|
||
goto eol;
|
||
if (is_name_beginner (c)) /* here if did not begin with a digit */
|
||
{
|
||
/*
|
||
* Identifier begins here.
|
||
* This is kludged for speed, so code is repeated.
|
||
*/
|
||
isname:
|
||
name = --input_line_pointer;
|
||
c = get_symbol_end ();
|
||
|
||
#ifdef md_parse_name
|
||
/* This is a hook for the backend to parse certain names
|
||
specially in certain contexts. If a name always has a
|
||
specific value, it can often be handled by simply
|
||
entering it in the symbol table. */
|
||
if (md_parse_name (name, expressionP))
|
||
{
|
||
*input_line_pointer = c;
|
||
break;
|
||
}
|
||
#endif
|
||
|
||
#ifdef TC_I960
|
||
/* The MRI i960 assembler permits
|
||
lda sizeof code,g13
|
||
FIXME: This should use md_parse_name. */
|
||
if (flag_mri
|
||
&& (strcasecmp (name, "sizeof") == 0
|
||
|| strcasecmp (name, "startof") == 0))
|
||
{
|
||
int start;
|
||
char *buf;
|
||
|
||
start = (name[1] == 't'
|
||
|| name[1] == 'T');
|
||
|
||
*input_line_pointer = c;
|
||
SKIP_WHITESPACE ();
|
||
|
||
name = input_line_pointer;
|
||
c = get_symbol_end ();
|
||
|
||
buf = (char *) xmalloc (strlen (name) + 10);
|
||
if (start)
|
||
sprintf (buf, ".startof.%s", name);
|
||
else
|
||
sprintf (buf, ".sizeof.%s", name);
|
||
symbolP = symbol_make (buf);
|
||
free (buf);
|
||
|
||
expressionP->X_op = O_symbol;
|
||
expressionP->X_add_symbol = symbolP;
|
||
expressionP->X_add_number = 0;
|
||
|
||
*input_line_pointer = c;
|
||
SKIP_WHITESPACE ();
|
||
|
||
break;
|
||
}
|
||
#endif
|
||
|
||
symbolP = symbol_find_or_make (name);
|
||
|
||
/* If we have an absolute symbol or a reg, then we know its
|
||
value now. */
|
||
segment = S_GET_SEGMENT (symbolP);
|
||
if (segment == absolute_section)
|
||
{
|
||
expressionP->X_op = O_constant;
|
||
expressionP->X_add_number = S_GET_VALUE (symbolP);
|
||
}
|
||
else if (segment == reg_section)
|
||
{
|
||
expressionP->X_op = O_register;
|
||
expressionP->X_add_number = S_GET_VALUE (symbolP);
|
||
}
|
||
else
|
||
{
|
||
expressionP->X_op = O_symbol;
|
||
expressionP->X_add_symbol = symbolP;
|
||
expressionP->X_add_number = 0;
|
||
}
|
||
*input_line_pointer = c;
|
||
}
|
||
else
|
||
{
|
||
/* Let the target try to parse it. Success is indicated by changing
|
||
the X_op field to something other than O_absent and pointing
|
||
input_line_pointer passed the expression. If it can't parse the
|
||
expression, X_op and input_line_pointer should be unchanged. */
|
||
expressionP->X_op = O_absent;
|
||
--input_line_pointer;
|
||
md_operand (expressionP);
|
||
if (expressionP->X_op == O_absent)
|
||
{
|
||
++input_line_pointer;
|
||
as_bad (_("Bad expression"));
|
||
expressionP->X_op = O_constant;
|
||
expressionP->X_add_number = 0;
|
||
}
|
||
}
|
||
break;
|
||
}
|
||
|
||
/*
|
||
* It is more 'efficient' to clean up the expressionS when they are created.
|
||
* Doing it here saves lines of code.
|
||
*/
|
||
clean_up_expression (expressionP);
|
||
SKIP_WHITESPACE (); /*->1st char after operand. */
|
||
know (*input_line_pointer != ' ');
|
||
|
||
/* The PA port needs this information. */
|
||
if (expressionP->X_add_symbol)
|
||
symbol_mark_used (expressionP->X_add_symbol);
|
||
|
||
switch (expressionP->X_op)
|
||
{
|
||
default:
|
||
return absolute_section;
|
||
case O_symbol:
|
||
return S_GET_SEGMENT (expressionP->X_add_symbol);
|
||
case O_register:
|
||
return reg_section;
|
||
}
|
||
} /* operand() */
|
||
|
||
/* Internal. Simplify a struct expression for use by expr() */
|
||
|
||
/*
|
||
* In: address of a expressionS.
|
||
* The X_op field of the expressionS may only take certain values.
|
||
* Elsewise we waste time special-case testing. Sigh. Ditto SEG_ABSENT.
|
||
* Out: expressionS may have been modified:
|
||
* 'foo-foo' symbol references cancelled to 0,
|
||
* which changes X_op from O_subtract to O_constant.
|
||
* Unused fields zeroed to help expr().
|
||
*/
|
||
|
||
static void
|
||
clean_up_expression (expressionP)
|
||
expressionS *expressionP;
|
||
{
|
||
switch (expressionP->X_op)
|
||
{
|
||
case O_illegal:
|
||
case O_absent:
|
||
expressionP->X_add_number = 0;
|
||
/* Fall through. */
|
||
case O_big:
|
||
case O_constant:
|
||
case O_register:
|
||
expressionP->X_add_symbol = NULL;
|
||
/* Fall through. */
|
||
case O_symbol:
|
||
case O_uminus:
|
||
case O_bit_not:
|
||
expressionP->X_op_symbol = NULL;
|
||
break;
|
||
case O_subtract:
|
||
if (expressionP->X_op_symbol == expressionP->X_add_symbol
|
||
|| ((symbol_get_frag (expressionP->X_op_symbol)
|
||
== symbol_get_frag (expressionP->X_add_symbol))
|
||
&& SEG_NORMAL (S_GET_SEGMENT (expressionP->X_add_symbol))
|
||
&& (S_GET_VALUE (expressionP->X_op_symbol)
|
||
== S_GET_VALUE (expressionP->X_add_symbol))))
|
||
{
|
||
addressT diff = (S_GET_VALUE (expressionP->X_add_symbol)
|
||
- S_GET_VALUE (expressionP->X_op_symbol));
|
||
|
||
expressionP->X_op = O_constant;
|
||
expressionP->X_add_symbol = NULL;
|
||
expressionP->X_op_symbol = NULL;
|
||
expressionP->X_add_number += diff;
|
||
}
|
||
break;
|
||
default:
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Expression parser. */
|
||
|
||
/*
|
||
* We allow an empty expression, and just assume (absolute,0) silently.
|
||
* Unary operators and parenthetical expressions are treated as operands.
|
||
* As usual, Q==quantity==operand, O==operator, X==expression mnemonics.
|
||
*
|
||
* We used to do a aho/ullman shift-reduce parser, but the logic got so
|
||
* warped that I flushed it and wrote a recursive-descent parser instead.
|
||
* Now things are stable, would anybody like to write a fast parser?
|
||
* Most expressions are either register (which does not even reach here)
|
||
* or 1 symbol. Then "symbol+constant" and "symbol-symbol" are common.
|
||
* So I guess it doesn't really matter how inefficient more complex expressions
|
||
* are parsed.
|
||
*
|
||
* After expr(RANK,resultP) input_line_pointer->operator of rank <= RANK.
|
||
* Also, we have consumed any leading or trailing spaces (operand does that)
|
||
* and done all intervening operators.
|
||
*
|
||
* This returns the segment of the result, which will be
|
||
* absolute_section or the segment of a symbol.
|
||
*/
|
||
|
||
#undef __
|
||
#define __ O_illegal
|
||
|
||
static const operatorT op_encoding[256] =
|
||
{ /* maps ASCII->operators */
|
||
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
|
||
__, O_bit_or_not, __, __, __, O_modulus, O_bit_and, __,
|
||
__, __, O_multiply, O_add, __, O_subtract, __, O_divide,
|
||
__, __, __, __, __, __, __, __,
|
||
__, __, __, __, O_lt, __, O_gt, __,
|
||
__, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __,
|
||
__, __, __,
|
||
#ifdef NEED_INDEX_OPERATOR
|
||
O_index,
|
||
#else
|
||
__,
|
||
#endif
|
||
__, __, O_bit_exclusive_or, __,
|
||
__, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __,
|
||
__, __, __, __, O_bit_inclusive_or, __, __, __,
|
||
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __
|
||
};
|
||
|
||
|
||
/*
|
||
* Rank Examples
|
||
* 0 operand, (expression)
|
||
* 1 ||
|
||
* 2 &&
|
||
* 3 = <> < <= >= >
|
||
* 4 + -
|
||
* 5 used for * / % in MRI mode
|
||
* 6 & ^ ! |
|
||
* 7 * / % << >>
|
||
* 8 unary - unary ~
|
||
*/
|
||
static operator_rankT op_rank[] =
|
||
{
|
||
0, /* O_illegal */
|
||
0, /* O_absent */
|
||
0, /* O_constant */
|
||
0, /* O_symbol */
|
||
0, /* O_symbol_rva */
|
||
0, /* O_register */
|
||
0, /* O_bit */
|
||
9, /* O_uminus */
|
||
9, /* O_bit_not */
|
||
9, /* O_logical_not */
|
||
8, /* O_multiply */
|
||
8, /* O_divide */
|
||
8, /* O_modulus */
|
||
8, /* O_left_shift */
|
||
8, /* O_right_shift */
|
||
7, /* O_bit_inclusive_or */
|
||
7, /* O_bit_or_not */
|
||
7, /* O_bit_exclusive_or */
|
||
7, /* O_bit_and */
|
||
5, /* O_add */
|
||
5, /* O_subtract */
|
||
4, /* O_eq */
|
||
4, /* O_ne */
|
||
4, /* O_lt */
|
||
4, /* O_le */
|
||
4, /* O_ge */
|
||
4, /* O_gt */
|
||
3, /* O_logical_and */
|
||
2, /* O_logical_or */
|
||
1, /* O_index */
|
||
};
|
||
|
||
/* Unfortunately, in MRI mode for the m68k, multiplication and
|
||
division have lower precedence than the bit wise operators. This
|
||
function sets the operator precedences correctly for the current
|
||
mode. Also, MRI uses a different bit_not operator, and this fixes
|
||
that as well. */
|
||
|
||
#define STANDARD_MUL_PRECEDENCE (7)
|
||
#define MRI_MUL_PRECEDENCE (5)
|
||
|
||
void
|
||
expr_set_precedence ()
|
||
{
|
||
if (flag_m68k_mri)
|
||
{
|
||
op_rank[O_multiply] = MRI_MUL_PRECEDENCE;
|
||
op_rank[O_divide] = MRI_MUL_PRECEDENCE;
|
||
op_rank[O_modulus] = MRI_MUL_PRECEDENCE;
|
||
}
|
||
else
|
||
{
|
||
op_rank[O_multiply] = STANDARD_MUL_PRECEDENCE;
|
||
op_rank[O_divide] = STANDARD_MUL_PRECEDENCE;
|
||
op_rank[O_modulus] = STANDARD_MUL_PRECEDENCE;
|
||
}
|
||
}
|
||
|
||
/* Initialize the expression parser. */
|
||
|
||
void
|
||
expr_begin ()
|
||
{
|
||
expr_set_precedence ();
|
||
|
||
/* Verify that X_op field is wide enough. */
|
||
{
|
||
expressionS e;
|
||
e.X_op = O_max;
|
||
assert (e.X_op == O_max);
|
||
}
|
||
}
|
||
|
||
/* Return the encoding for the operator at INPUT_LINE_POINTER.
|
||
Advance INPUT_LINE_POINTER to the last character in the operator
|
||
(i.e., don't change it for a single character operator). */
|
||
|
||
static inline operatorT
|
||
operator ()
|
||
{
|
||
int c;
|
||
operatorT ret;
|
||
|
||
c = *input_line_pointer & 0xff;
|
||
|
||
switch (c)
|
||
{
|
||
default:
|
||
return op_encoding[c];
|
||
|
||
case '<':
|
||
switch (input_line_pointer[1])
|
||
{
|
||
default:
|
||
return op_encoding[c];
|
||
case '<':
|
||
ret = O_left_shift;
|
||
break;
|
||
case '>':
|
||
ret = O_ne;
|
||
break;
|
||
case '=':
|
||
ret = O_le;
|
||
break;
|
||
}
|
||
++input_line_pointer;
|
||
return ret;
|
||
|
||
case '=':
|
||
if (input_line_pointer[1] != '=')
|
||
return op_encoding[c];
|
||
|
||
++input_line_pointer;
|
||
return O_eq;
|
||
|
||
case '>':
|
||
switch (input_line_pointer[1])
|
||
{
|
||
default:
|
||
return op_encoding[c];
|
||
case '>':
|
||
ret = O_right_shift;
|
||
break;
|
||
case '=':
|
||
ret = O_ge;
|
||
break;
|
||
}
|
||
++input_line_pointer;
|
||
return ret;
|
||
|
||
case '!':
|
||
/* We accept !! as equivalent to ^ for MRI compatibility. */
|
||
if (input_line_pointer[1] != '!')
|
||
{
|
||
if (flag_m68k_mri)
|
||
return O_bit_inclusive_or;
|
||
return op_encoding[c];
|
||
}
|
||
++input_line_pointer;
|
||
return O_bit_exclusive_or;
|
||
|
||
case '|':
|
||
if (input_line_pointer[1] != '|')
|
||
return op_encoding[c];
|
||
|
||
++input_line_pointer;
|
||
return O_logical_or;
|
||
|
||
case '&':
|
||
if (input_line_pointer[1] != '&')
|
||
return op_encoding[c];
|
||
|
||
++input_line_pointer;
|
||
return O_logical_and;
|
||
}
|
||
|
||
/*NOTREACHED*/
|
||
}
|
||
|
||
/* Parse an expression. */
|
||
|
||
segT
|
||
expr (rankarg, resultP)
|
||
int rankarg; /* Larger # is higher rank. */
|
||
expressionS *resultP; /* Deliver result here. */
|
||
{
|
||
operator_rankT rank = (operator_rankT) rankarg;
|
||
segT retval;
|
||
expressionS right;
|
||
operatorT op_left;
|
||
operatorT op_right;
|
||
|
||
know (rank >= 0);
|
||
|
||
retval = operand (resultP);
|
||
|
||
know (*input_line_pointer != ' '); /* Operand() gobbles spaces. */
|
||
|
||
op_left = operator ();
|
||
while (op_left != O_illegal && op_rank[(int) op_left] > rank)
|
||
{
|
||
segT rightseg;
|
||
|
||
input_line_pointer++; /*->after 1st character of operator. */
|
||
|
||
rightseg = expr (op_rank[(int) op_left], &right);
|
||
if (right.X_op == O_absent)
|
||
{
|
||
as_warn (_("missing operand; zero assumed"));
|
||
right.X_op = O_constant;
|
||
right.X_add_number = 0;
|
||
right.X_add_symbol = NULL;
|
||
right.X_op_symbol = NULL;
|
||
}
|
||
|
||
know (*input_line_pointer != ' ');
|
||
|
||
if (op_left == O_index)
|
||
{
|
||
if (*input_line_pointer != ']')
|
||
as_bad ("missing right bracket");
|
||
else
|
||
{
|
||
++input_line_pointer;
|
||
SKIP_WHITESPACE ();
|
||
}
|
||
}
|
||
|
||
if (retval == undefined_section)
|
||
{
|
||
if (SEG_NORMAL (rightseg))
|
||
retval = rightseg;
|
||
}
|
||
else if (! SEG_NORMAL (retval))
|
||
retval = rightseg;
|
||
else if (SEG_NORMAL (rightseg)
|
||
&& retval != rightseg
|
||
#ifdef DIFF_EXPR_OK
|
||
&& op_left != O_subtract
|
||
#endif
|
||
)
|
||
as_bad (_("operation combines symbols in different segments"));
|
||
|
||
op_right = operator ();
|
||
|
||
know (op_right == O_illegal || op_rank[(int) op_right] <= op_rank[(int) op_left]);
|
||
know ((int) op_left >= (int) O_multiply
|
||
&& (int) op_left <= (int) O_logical_or);
|
||
|
||
/* input_line_pointer->after right-hand quantity. */
|
||
/* left-hand quantity in resultP */
|
||
/* right-hand quantity in right. */
|
||
/* operator in op_left. */
|
||
|
||
if (resultP->X_op == O_big)
|
||
{
|
||
if (resultP->X_add_number > 0)
|
||
as_warn (_("left operand is a bignum; integer 0 assumed"));
|
||
else
|
||
as_warn (_("left operand is a float; integer 0 assumed"));
|
||
resultP->X_op = O_constant;
|
||
resultP->X_add_number = 0;
|
||
resultP->X_add_symbol = NULL;
|
||
resultP->X_op_symbol = NULL;
|
||
}
|
||
if (right.X_op == O_big)
|
||
{
|
||
if (right.X_add_number > 0)
|
||
as_warn (_("right operand is a bignum; integer 0 assumed"));
|
||
else
|
||
as_warn (_("right operand is a float; integer 0 assumed"));
|
||
right.X_op = O_constant;
|
||
right.X_add_number = 0;
|
||
right.X_add_symbol = NULL;
|
||
right.X_op_symbol = NULL;
|
||
}
|
||
|
||
/* Optimize common cases. */
|
||
if (op_left == O_add && right.X_op == O_constant)
|
||
{
|
||
/* X + constant. */
|
||
resultP->X_add_number += right.X_add_number;
|
||
}
|
||
/* This case comes up in PIC code. */
|
||
else if (op_left == O_subtract
|
||
&& right.X_op == O_symbol
|
||
&& resultP->X_op == O_symbol
|
||
&& (symbol_get_frag (right.X_add_symbol)
|
||
== symbol_get_frag (resultP->X_add_symbol))
|
||
&& SEG_NORMAL (S_GET_SEGMENT (right.X_add_symbol)))
|
||
|
||
{
|
||
resultP->X_add_number -= right.X_add_number;
|
||
resultP->X_add_number += (S_GET_VALUE (resultP->X_add_symbol)
|
||
- S_GET_VALUE (right.X_add_symbol));
|
||
resultP->X_op = O_constant;
|
||
resultP->X_add_symbol = 0;
|
||
}
|
||
else if (op_left == O_subtract && right.X_op == O_constant)
|
||
{
|
||
/* X - constant. */
|
||
resultP->X_add_number -= right.X_add_number;
|
||
}
|
||
else if (op_left == O_add && resultP->X_op == O_constant)
|
||
{
|
||
/* Constant + X. */
|
||
resultP->X_op = right.X_op;
|
||
resultP->X_add_symbol = right.X_add_symbol;
|
||
resultP->X_op_symbol = right.X_op_symbol;
|
||
resultP->X_add_number += right.X_add_number;
|
||
retval = rightseg;
|
||
}
|
||
else if (resultP->X_op == O_constant && right.X_op == O_constant)
|
||
{
|
||
/* Constant OP constant. */
|
||
offsetT v = right.X_add_number;
|
||
if (v == 0 && (op_left == O_divide || op_left == O_modulus))
|
||
{
|
||
as_warn (_("division by zero"));
|
||
v = 1;
|
||
}
|
||
switch (op_left)
|
||
{
|
||
default: abort ();
|
||
case O_multiply: resultP->X_add_number *= v; break;
|
||
case O_divide: resultP->X_add_number /= v; break;
|
||
case O_modulus: resultP->X_add_number %= v; break;
|
||
case O_left_shift: resultP->X_add_number <<= v; break;
|
||
case O_right_shift:
|
||
/* We always use unsigned shifts, to avoid relying on
|
||
characteristics of the compiler used to compile gas. */
|
||
resultP->X_add_number =
|
||
(offsetT) ((valueT) resultP->X_add_number >> (valueT) v);
|
||
break;
|
||
case O_bit_inclusive_or: resultP->X_add_number |= v; break;
|
||
case O_bit_or_not: resultP->X_add_number |= ~v; break;
|
||
case O_bit_exclusive_or: resultP->X_add_number ^= v; break;
|
||
case O_bit_and: resultP->X_add_number &= v; break;
|
||
case O_add: resultP->X_add_number += v; break;
|
||
case O_subtract: resultP->X_add_number -= v; break;
|
||
case O_eq:
|
||
resultP->X_add_number =
|
||
resultP->X_add_number == v ? ~ (offsetT) 0 : 0;
|
||
break;
|
||
case O_ne:
|
||
resultP->X_add_number =
|
||
resultP->X_add_number != v ? ~ (offsetT) 0 : 0;
|
||
break;
|
||
case O_lt:
|
||
resultP->X_add_number =
|
||
resultP->X_add_number < v ? ~ (offsetT) 0 : 0;
|
||
break;
|
||
case O_le:
|
||
resultP->X_add_number =
|
||
resultP->X_add_number <= v ? ~ (offsetT) 0 : 0;
|
||
break;
|
||
case O_ge:
|
||
resultP->X_add_number =
|
||
resultP->X_add_number >= v ? ~ (offsetT) 0 : 0;
|
||
break;
|
||
case O_gt:
|
||
resultP->X_add_number =
|
||
resultP->X_add_number > v ? ~ (offsetT) 0 : 0;
|
||
break;
|
||
case O_logical_and:
|
||
resultP->X_add_number = resultP->X_add_number && v;
|
||
break;
|
||
case O_logical_or:
|
||
resultP->X_add_number = resultP->X_add_number || v;
|
||
break;
|
||
}
|
||
}
|
||
else if (resultP->X_op == O_symbol
|
||
&& right.X_op == O_symbol
|
||
&& (op_left == O_add
|
||
|| op_left == O_subtract
|
||
|| (resultP->X_add_number == 0
|
||
&& right.X_add_number == 0)))
|
||
{
|
||
/* Symbol OP symbol. */
|
||
resultP->X_op = op_left;
|
||
resultP->X_op_symbol = right.X_add_symbol;
|
||
if (op_left == O_add)
|
||
resultP->X_add_number += right.X_add_number;
|
||
else if (op_left == O_subtract)
|
||
resultP->X_add_number -= right.X_add_number;
|
||
}
|
||
else
|
||
{
|
||
/* The general case. */
|
||
resultP->X_add_symbol = make_expr_symbol (resultP);
|
||
resultP->X_op_symbol = make_expr_symbol (&right);
|
||
resultP->X_op = op_left;
|
||
resultP->X_add_number = 0;
|
||
resultP->X_unsigned = 1;
|
||
}
|
||
|
||
op_left = op_right;
|
||
} /* While next operator is >= this rank. */
|
||
|
||
/* The PA port needs this information. */
|
||
if (resultP->X_add_symbol)
|
||
symbol_mark_used (resultP->X_add_symbol);
|
||
|
||
return resultP->X_op == O_constant ? absolute_section : retval;
|
||
}
|
||
|
||
/*
|
||
* get_symbol_end()
|
||
*
|
||
* This lives here because it belongs equally in expr.c & read.c.
|
||
* Expr.c is just a branch office read.c anyway, and putting it
|
||
* here lessens the crowd at read.c.
|
||
*
|
||
* Assume input_line_pointer is at start of symbol name.
|
||
* Advance input_line_pointer past symbol name.
|
||
* Turn that character into a '\0', returning its former value.
|
||
* This allows a string compare (RMS wants symbol names to be strings)
|
||
* of the symbol name.
|
||
* There will always be a char following symbol name, because all good
|
||
* lines end in end-of-line.
|
||
*/
|
||
char
|
||
get_symbol_end ()
|
||
{
|
||
char c;
|
||
|
||
/* We accept \001 in a name in case this is being called with a
|
||
constructed string. */
|
||
if (is_name_beginner (c = *input_line_pointer++) || c == '\001')
|
||
{
|
||
while (is_part_of_name (c = *input_line_pointer++)
|
||
|| c == '\001')
|
||
;
|
||
if (is_name_ender (c))
|
||
c = *input_line_pointer++;
|
||
}
|
||
*--input_line_pointer = 0;
|
||
return (c);
|
||
}
|
||
|
||
|
||
unsigned int
|
||
get_single_number ()
|
||
{
|
||
expressionS exp;
|
||
operand (&exp);
|
||
return exp.X_add_number;
|
||
|
||
}
|
||
|
||
/* end of expr.c */
|