1918 lines
50 KiB
C
1918 lines
50 KiB
C
/* expr.c -operands, expressions-
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Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
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1999, 2000, 2001, 2002
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Free Software Foundation, Inc.
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This file is part of GAS, the GNU Assembler.
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GAS 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
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GAS is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GAS; see the file COPYING. If not, write to the Free
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Software Foundation, 59 Temple Place - Suite 330, Boston, MA
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02111-1307, USA. */
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/* This is really a branch office of as-read.c. I split it out to clearly
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distinguish the world of expressions from the world of statements.
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(It also gives smaller files to re-compile.)
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Here, "operand"s are of expressions, not instructions. */
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#include <string.h>
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#define min(a, b) ((a) < (b) ? (a) : (b))
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#include "as.h"
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#include "safe-ctype.h"
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#include "obstack.h"
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static void floating_constant (expressionS * expressionP);
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static valueT generic_bignum_to_int32 (void);
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#ifdef BFD64
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static valueT generic_bignum_to_int64 (void);
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#endif
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static void integer_constant (int radix, expressionS * expressionP);
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static void mri_char_constant (expressionS *);
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static void current_location (expressionS *);
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static void clean_up_expression (expressionS * expressionP);
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static segT operand (expressionS *);
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static operatorT operator (int *);
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extern const char EXP_CHARS[], FLT_CHARS[];
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/* We keep a mapping of expression symbols to file positions, so that
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we can provide better error messages. */
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struct expr_symbol_line {
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struct expr_symbol_line *next;
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symbolS *sym;
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char *file;
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unsigned int line;
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};
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static struct expr_symbol_line *expr_symbol_lines;
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/* Build a dummy symbol to hold a complex expression. This is how we
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build expressions up out of other expressions. The symbol is put
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into the fake section expr_section. */
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symbolS *
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make_expr_symbol (expressionS *expressionP)
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{
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expressionS zero;
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symbolS *symbolP;
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struct expr_symbol_line *n;
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if (expressionP->X_op == O_symbol
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&& expressionP->X_add_number == 0)
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return expressionP->X_add_symbol;
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if (expressionP->X_op == O_big)
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{
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/* This won't work, because the actual value is stored in
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generic_floating_point_number or generic_bignum, and we are
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going to lose it if we haven't already. */
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if (expressionP->X_add_number > 0)
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as_bad (_("bignum invalid"));
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else
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as_bad (_("floating point number invalid"));
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zero.X_op = O_constant;
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zero.X_add_number = 0;
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zero.X_unsigned = 0;
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clean_up_expression (&zero);
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expressionP = &zero;
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}
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/* Putting constant symbols in absolute_section rather than
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expr_section is convenient for the old a.out code, for which
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S_GET_SEGMENT does not always retrieve the value put in by
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S_SET_SEGMENT. */
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symbolP = symbol_create (FAKE_LABEL_NAME,
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(expressionP->X_op == O_constant
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? absolute_section
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: expr_section),
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0, &zero_address_frag);
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symbol_set_value_expression (symbolP, expressionP);
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if (expressionP->X_op == O_constant)
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resolve_symbol_value (symbolP);
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n = (struct expr_symbol_line *) xmalloc (sizeof *n);
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n->sym = symbolP;
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as_where (&n->file, &n->line);
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n->next = expr_symbol_lines;
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expr_symbol_lines = n;
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return symbolP;
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}
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/* Return the file and line number for an expr symbol. Return
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non-zero if something was found, 0 if no information is known for
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the symbol. */
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int
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expr_symbol_where (symbolS *sym, char **pfile, unsigned int *pline)
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{
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register struct expr_symbol_line *l;
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for (l = expr_symbol_lines; l != NULL; l = l->next)
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{
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if (l->sym == sym)
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{
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*pfile = l->file;
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*pline = l->line;
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return 1;
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}
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}
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return 0;
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}
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/* Utilities for building expressions.
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Since complex expressions are recorded as symbols for use in other
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expressions these return a symbolS * and not an expressionS *.
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These explicitly do not take an "add_number" argument. */
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/* ??? For completeness' sake one might want expr_build_symbol.
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It would just return its argument. */
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/* Build an expression for an unsigned constant.
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The corresponding one for signed constants is missing because
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there's currently no need for it. One could add an unsigned_p flag
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but that seems more clumsy. */
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symbolS *
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expr_build_uconstant (offsetT value)
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{
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expressionS e;
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e.X_op = O_constant;
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e.X_add_number = value;
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e.X_unsigned = 1;
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return make_expr_symbol (&e);
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}
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/* Build an expression for OP s1. */
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symbolS *
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expr_build_unary (operatorT op, symbolS *s1)
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{
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expressionS e;
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e.X_op = op;
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e.X_add_symbol = s1;
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e.X_add_number = 0;
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return make_expr_symbol (&e);
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}
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/* Build an expression for s1 OP s2. */
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symbolS *
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expr_build_binary (operatorT op, symbolS *s1, symbolS *s2)
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{
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expressionS e;
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e.X_op = op;
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e.X_add_symbol = s1;
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e.X_op_symbol = s2;
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e.X_add_number = 0;
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return make_expr_symbol (&e);
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}
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/* Build an expression for the current location ('.'). */
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symbolS *
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expr_build_dot (void)
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{
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expressionS e;
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current_location (&e);
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return make_expr_symbol (&e);
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}
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/* Build any floating-point literal here.
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Also build any bignum literal here. */
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/* Seems atof_machine can backscan through generic_bignum and hit whatever
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happens to be loaded before it in memory. And its way too complicated
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for me to fix right. Thus a hack. JF: Just make generic_bignum bigger,
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and never write into the early words, thus they'll always be zero.
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I hate Dean's floating-point code. Bleh. */
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LITTLENUM_TYPE generic_bignum[SIZE_OF_LARGE_NUMBER + 6];
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FLONUM_TYPE generic_floating_point_number = {
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&generic_bignum[6], /* low. (JF: Was 0) */
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&generic_bignum[SIZE_OF_LARGE_NUMBER + 6 - 1], /* high. JF: (added +6) */
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0, /* leader. */
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0, /* exponent. */
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0 /* sign. */
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};
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/* If nonzero, we've been asked to assemble nan, +inf or -inf. */
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int generic_floating_point_magic;
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static void
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floating_constant (expressionS *expressionP)
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{
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/* input_line_pointer -> floating-point constant. */
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int error_code;
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error_code = atof_generic (&input_line_pointer, ".", EXP_CHARS,
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&generic_floating_point_number);
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if (error_code)
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{
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if (error_code == ERROR_EXPONENT_OVERFLOW)
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{
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as_bad (_("bad floating-point constant: exponent overflow"));
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}
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else
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{
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as_bad (_("bad floating-point constant: unknown error code=%d"),
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error_code);
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}
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}
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expressionP->X_op = O_big;
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/* input_line_pointer -> just after constant, which may point to
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whitespace. */
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expressionP->X_add_number = -1;
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}
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static valueT
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generic_bignum_to_int32 (void)
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{
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valueT number =
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((generic_bignum[1] & LITTLENUM_MASK) << LITTLENUM_NUMBER_OF_BITS)
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| (generic_bignum[0] & LITTLENUM_MASK);
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number &= 0xffffffff;
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return number;
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}
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#ifdef BFD64
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static valueT
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generic_bignum_to_int64 (void)
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{
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valueT number =
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((((((((valueT) generic_bignum[3] & LITTLENUM_MASK)
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<< LITTLENUM_NUMBER_OF_BITS)
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| ((valueT) generic_bignum[2] & LITTLENUM_MASK))
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<< LITTLENUM_NUMBER_OF_BITS)
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| ((valueT) generic_bignum[1] & LITTLENUM_MASK))
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<< LITTLENUM_NUMBER_OF_BITS)
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| ((valueT) generic_bignum[0] & LITTLENUM_MASK));
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return number;
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}
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#endif
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static void
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integer_constant (int radix, expressionS *expressionP)
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{
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char *start; /* Start of number. */
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char *suffix = NULL;
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char c;
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valueT number; /* Offset or (absolute) value. */
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short int digit; /* Value of next digit in current radix. */
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short int maxdig = 0; /* Highest permitted digit value. */
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int too_many_digits = 0; /* If we see >= this number of. */
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char *name; /* Points to name of symbol. */
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symbolS *symbolP; /* Points to symbol. */
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int small; /* True if fits in 32 bits. */
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/* May be bignum, or may fit in 32 bits. */
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/* Most numbers fit into 32 bits, and we want this case to be fast.
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so we pretend it will fit into 32 bits. If, after making up a 32
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bit number, we realise that we have scanned more digits than
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comfortably fit into 32 bits, we re-scan the digits coding them
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into a bignum. For decimal and octal numbers we are
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conservative: Some numbers may be assumed bignums when in fact
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they do fit into 32 bits. Numbers of any radix can have excess
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leading zeros: We strive to recognise this and cast them back
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into 32 bits. We must check that the bignum really is more than
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32 bits, and change it back to a 32-bit number if it fits. The
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number we are looking for is expected to be positive, but if it
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fits into 32 bits as an unsigned number, we let it be a 32-bit
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number. The cavalier approach is for speed in ordinary cases. */
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/* This has been extended for 64 bits. We blindly assume that if
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you're compiling in 64-bit mode, the target is a 64-bit machine.
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This should be cleaned up. */
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#ifdef BFD64
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#define valuesize 64
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#else /* includes non-bfd case, mostly */
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#define valuesize 32
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#endif
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if ((NUMBERS_WITH_SUFFIX || flag_m68k_mri) && radix == 0)
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{
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int flt = 0;
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/* In MRI mode, the number may have a suffix indicating the
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radix. For that matter, it might actually be a floating
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point constant. */
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for (suffix = input_line_pointer; ISALNUM (*suffix); suffix++)
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{
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if (*suffix == 'e' || *suffix == 'E')
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flt = 1;
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}
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if (suffix == input_line_pointer)
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{
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radix = 10;
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suffix = NULL;
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}
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else
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{
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c = *--suffix;
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c = TOUPPER (c);
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if (c == 'B')
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radix = 2;
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else if (c == 'D')
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radix = 10;
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else if (c == 'O' || c == 'Q')
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radix = 8;
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else if (c == 'H')
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radix = 16;
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else if (suffix[1] == '.' || c == 'E' || flt)
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{
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floating_constant (expressionP);
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return;
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}
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else
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{
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radix = 10;
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suffix = NULL;
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}
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}
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}
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switch (radix)
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{
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case 2:
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maxdig = 2;
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too_many_digits = valuesize + 1;
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break;
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case 8:
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maxdig = radix = 8;
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too_many_digits = (valuesize + 2) / 3 + 1;
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break;
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case 16:
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maxdig = radix = 16;
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too_many_digits = (valuesize + 3) / 4 + 1;
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break;
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case 10:
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maxdig = radix = 10;
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too_many_digits = (valuesize + 11) / 4; /* Very rough. */
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}
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#undef valuesize
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start = input_line_pointer;
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c = *input_line_pointer++;
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for (number = 0;
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(digit = hex_value (c)) < maxdig;
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c = *input_line_pointer++)
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{
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number = number * radix + digit;
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}
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/* c contains character after number. */
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/* input_line_pointer->char after c. */
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small = (input_line_pointer - start - 1) < too_many_digits;
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if (radix == 16 && c == '_')
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{
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/* This is literal of the form 0x333_0_12345678_1.
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This example is equivalent to 0x00000333000000001234567800000001. */
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int num_little_digits = 0;
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int i;
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input_line_pointer = start; /* -> 1st digit. */
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know (LITTLENUM_NUMBER_OF_BITS == 16);
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for (c = '_'; c == '_'; num_little_digits += 2)
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{
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/* Convert one 64-bit word. */
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int ndigit = 0;
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number = 0;
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for (c = *input_line_pointer++;
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(digit = hex_value (c)) < maxdig;
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c = *(input_line_pointer++))
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{
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number = number * radix + digit;
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ndigit++;
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}
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/* Check for 8 digit per word max. */
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if (ndigit > 8)
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as_bad (_("a bignum with underscores may not have more than 8 hex digits in any word"));
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/* Add this chunk to the bignum.
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Shift things down 2 little digits. */
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know (LITTLENUM_NUMBER_OF_BITS == 16);
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for (i = min (num_little_digits + 1, SIZE_OF_LARGE_NUMBER - 1);
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i >= 2;
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i--)
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generic_bignum[i] = generic_bignum[i - 2];
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/* Add the new digits as the least significant new ones. */
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generic_bignum[0] = number & 0xffffffff;
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generic_bignum[1] = number >> 16;
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}
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/* Again, c is char after number, input_line_pointer->after c. */
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if (num_little_digits > SIZE_OF_LARGE_NUMBER - 1)
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num_little_digits = SIZE_OF_LARGE_NUMBER - 1;
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assert (num_little_digits >= 4);
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if (num_little_digits != 8)
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as_bad (_("a bignum with underscores must have exactly 4 words"));
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/* We might have some leading zeros. These can be trimmed to give
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us a change to fit this constant into a small number. */
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while (generic_bignum[num_little_digits - 1] == 0
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&& num_little_digits > 1)
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num_little_digits--;
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if (num_little_digits <= 2)
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{
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/* will fit into 32 bits. */
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number = generic_bignum_to_int32 ();
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small = 1;
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}
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#ifdef BFD64
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else if (num_little_digits <= 4)
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{
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/* Will fit into 64 bits. */
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number = generic_bignum_to_int64 ();
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small = 1;
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}
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#endif
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else
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{
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small = 0;
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/* Number of littlenums in the bignum. */
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number = num_little_digits;
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}
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}
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else if (!small)
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{
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/* We saw a lot of digits. manufacture a bignum the hard way. */
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LITTLENUM_TYPE *leader; /* -> high order littlenum of the bignum. */
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LITTLENUM_TYPE *pointer; /* -> littlenum we are frobbing now. */
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long carry;
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leader = generic_bignum;
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generic_bignum[0] = 0;
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generic_bignum[1] = 0;
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generic_bignum[2] = 0;
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generic_bignum[3] = 0;
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input_line_pointer = start; /* -> 1st digit. */
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c = *input_line_pointer++;
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for (; (carry = hex_value (c)) < maxdig; c = *input_line_pointer++)
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{
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for (pointer = generic_bignum; pointer <= leader; pointer++)
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{
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long work;
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work = carry + radix * *pointer;
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*pointer = work & LITTLENUM_MASK;
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carry = work >> LITTLENUM_NUMBER_OF_BITS;
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}
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if (carry)
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{
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if (leader < generic_bignum + SIZE_OF_LARGE_NUMBER - 1)
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{
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/* Room to grow a longer bignum. */
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*++leader = carry;
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}
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}
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}
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/* Again, c is char after number. */
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/* input_line_pointer -> after c. */
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know (LITTLENUM_NUMBER_OF_BITS == 16);
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if (leader < generic_bignum + 2)
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{
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/* Will fit into 32 bits. */
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number = generic_bignum_to_int32 ();
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small = 1;
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}
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#ifdef BFD64
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else if (leader < generic_bignum + 4)
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{
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/* Will fit into 64 bits. */
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number = generic_bignum_to_int64 ();
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small = 1;
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}
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#endif
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else
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{
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/* Number of littlenums in the bignum. */
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number = leader - generic_bignum + 1;
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}
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}
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if ((NUMBERS_WITH_SUFFIX || flag_m68k_mri)
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&& suffix != NULL
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&& input_line_pointer - 1 == suffix)
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c = *input_line_pointer++;
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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 (_("backward ref to unknown label \"%d:\""),
|
||
(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 (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 (expressionS *expressionp)
|
||
{
|
||
if (now_seg == absolute_section)
|
||
{
|
||
expressionp->X_op = O_constant;
|
||
expressionp->X_add_number = abs_section_offset;
|
||
}
|
||
else
|
||
{
|
||
expressionp->X_op = O_symbol;
|
||
expressionp->X_add_symbol = symbol_temp_new_now ();
|
||
expressionp->X_add_number = 0;
|
||
}
|
||
}
|
||
|
||
/* In: Input_line_pointer points to 1st char of operand, which may
|
||
be a space.
|
||
|
||
Out: An 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 (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. */
|
||
|
||
if (is_end_of_line[(unsigned char) c])
|
||
goto eol;
|
||
|
||
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 ((NUMBERS_WITH_SUFFIX || flag_m68k_mri)
|
||
? 0 : 10,
|
||
expressionP);
|
||
break;
|
||
|
||
#ifdef LITERAL_PREFIXDOLLAR_HEX
|
||
case '$':
|
||
/* $L is the start of a local label, not a hex constant. */
|
||
if (* input_line_pointer == 'L')
|
||
goto isname;
|
||
integer_constant (16, expressionP);
|
||
break;
|
||
#endif
|
||
|
||
#ifdef LITERAL_PREFIXPERCENT_BIN
|
||
case '%':
|
||
integer_constant (2, expressionP);
|
||
break;
|
||
#endif
|
||
|
||
case '0':
|
||
/* Non-decimal radix. */
|
||
|
||
if (NUMBERS_WITH_SUFFIX || flag_m68k_mri)
|
||
{
|
||
char *s;
|
||
|
||
/* Check for a hex or float constant. */
|
||
for (s = input_line_pointer; hex_p (*s); s++)
|
||
;
|
||
if (*s == 'h' || *s == 'H' || *input_line_pointer == '.')
|
||
{
|
||
--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 (NUMBERS_WITH_SUFFIX || 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 = - TOLOWER (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 || NUMBERS_WITH_SUFFIX))
|
||
{
|
||
/* 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 || NUMBERS_WITH_SUFFIX)
|
||
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 || NUMBERS_WITH_SUFFIX)
|
||
? 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]])
|
||
|| strchr (FLT_CHARS, 'f') == NULL)
|
||
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 || NUMBERS_WITH_SUFFIX)
|
||
{
|
||
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 = - TOLOWER (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 != ']'))
|
||
{
|
||
#ifdef RELAX_PAREN_GROUPING
|
||
if (c != '(')
|
||
#endif
|
||
as_bad (_("missing '%c'"), c == '(' ? ')' : ']');
|
||
}
|
||
else
|
||
input_line_pointer++;
|
||
SKIP_WHITESPACE ();
|
||
/* Here with input_line_pointer -> char after "(...)". */
|
||
return segment;
|
||
|
||
#ifdef TC_M68K
|
||
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. */
|
||
#endif
|
||
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 '+':
|
||
/* Do not accept ++e as +(+e).
|
||
Disabled, since the preprocessor removes whitespace. */
|
||
if (0 && *input_line_pointer == '+')
|
||
goto target_op;
|
||
(void) operand (expressionP);
|
||
break;
|
||
|
||
#ifdef TC_M68K
|
||
case '"':
|
||
/* Double quote is the bitwise not operator in MRI mode. */
|
||
if (! flag_m68k_mri)
|
||
goto de_fault;
|
||
/* Fall through. */
|
||
#endif
|
||
case '~':
|
||
/* '~' is permitted to start a label on the Delta. */
|
||
if (is_name_beginner (c))
|
||
goto isname;
|
||
case '!':
|
||
case '-':
|
||
{
|
||
/* Do not accept --e as -(-e)
|
||
Disabled, since the preprocessor removes whitespace. */
|
||
if (0 && c == '-' && *input_line_pointer == '-')
|
||
goto target_op;
|
||
|
||
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_big
|
||
&& expressionP->X_add_number <= 0
|
||
&& c == '-'
|
||
&& (generic_floating_point_number.sign == '+'
|
||
|| generic_floating_point_number.sign == 'P'))
|
||
{
|
||
/* Negative flonum (eg, -1.000e0). */
|
||
if (generic_floating_point_number.sign == '+')
|
||
generic_floating_point_number.sign = '-';
|
||
else
|
||
generic_floating_point_number.sign = 'N';
|
||
}
|
||
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;
|
||
|
||
#if defined (DOLLAR_DOT) || defined (TC_M68K)
|
||
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;
|
||
#endif
|
||
|
||
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 ',':
|
||
eol:
|
||
/* Can't imagine any other kind of operand. */
|
||
expressionP->X_op = O_absent;
|
||
input_line_pointer--;
|
||
break;
|
||
|
||
#ifdef TC_M68K
|
||
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;
|
||
#endif
|
||
|
||
default:
|
||
#ifdef TC_M68K
|
||
de_fault:
|
||
#endif
|
||
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, &c))
|
||
{
|
||
*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
|
||
{
|
||
target_op:
|
||
/* 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 past 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;
|
||
}
|
||
}
|
||
|
||
/* Internal. Simplify a struct expression for use by expr (). */
|
||
|
||
/* In: address of an 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:
|
||
Unused fields zeroed to help expr (). */
|
||
|
||
static void
|
||
clean_up_expression (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;
|
||
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 an 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
|
||
|
||
/* Maps ASCII -> operators. */
|
||
static const operatorT op_encoding[256] = {
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
||
|
||
__, 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_big */
|
||
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 */
|
||
0, /* O_md1 */
|
||
0, /* O_md2 */
|
||
0, /* O_md3 */
|
||
0, /* O_md4 */
|
||
0, /* O_md5 */
|
||
0, /* O_md6 */
|
||
0, /* O_md7 */
|
||
0, /* O_md8 */
|
||
0, /* O_md9 */
|
||
0, /* O_md10 */
|
||
0, /* O_md11 */
|
||
0, /* O_md12 */
|
||
0, /* O_md13 */
|
||
0, /* O_md14 */
|
||
0, /* O_md15 */
|
||
0, /* O_md16 */
|
||
};
|
||
|
||
/* 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 8
|
||
#define MRI_MUL_PRECEDENCE 6
|
||
|
||
void
|
||
expr_set_precedence (void)
|
||
{
|
||
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 (void)
|
||
{
|
||
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, and
|
||
sets NUM_CHARS to the number of characters in the operator.
|
||
Does not advance INPUT_LINE_POINTER. */
|
||
|
||
static inline operatorT
|
||
operator (int *num_chars)
|
||
{
|
||
int c;
|
||
operatorT ret;
|
||
|
||
c = *input_line_pointer & 0xff;
|
||
*num_chars = 1;
|
||
|
||
if (is_end_of_line[c])
|
||
return O_illegal;
|
||
|
||
switch (c)
|
||
{
|
||
default:
|
||
return op_encoding[c];
|
||
|
||
case '+':
|
||
case '-':
|
||
/* Do not allow a++b and a--b to be a + (+b) and a - (-b)
|
||
Disabled, since the preprocessor removes whitespace. */
|
||
if (1 || input_line_pointer[1] != c)
|
||
return op_encoding[c];
|
||
return O_illegal;
|
||
|
||
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;
|
||
}
|
||
*num_chars = 2;
|
||
return ret;
|
||
|
||
case '=':
|
||
if (input_line_pointer[1] != '=')
|
||
return op_encoding[c];
|
||
|
||
*num_chars = 2;
|
||
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;
|
||
}
|
||
*num_chars = 2;
|
||
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];
|
||
}
|
||
*num_chars = 2;
|
||
return O_bit_exclusive_or;
|
||
|
||
case '|':
|
||
if (input_line_pointer[1] != '|')
|
||
return op_encoding[c];
|
||
|
||
*num_chars = 2;
|
||
return O_logical_or;
|
||
|
||
case '&':
|
||
if (input_line_pointer[1] != '&')
|
||
return op_encoding[c];
|
||
|
||
*num_chars = 2;
|
||
return O_logical_and;
|
||
}
|
||
|
||
/* NOTREACHED */
|
||
}
|
||
|
||
/* Parse an expression. */
|
||
|
||
segT
|
||
expr (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;
|
||
int op_chars;
|
||
|
||
know (rank >= 0);
|
||
|
||
/* Save the value of dot for the fixup code. */
|
||
if (rank == 0)
|
||
dot_value = frag_now_fix ();
|
||
|
||
retval = operand (resultP);
|
||
|
||
/* operand () gobbles spaces. */
|
||
know (*input_line_pointer != ' ');
|
||
|
||
op_left = operator (&op_chars);
|
||
while (op_left != O_illegal && op_rank[(int) op_left] > rank)
|
||
{
|
||
segT rightseg;
|
||
|
||
input_line_pointer += op_chars; /* -> after 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 ();
|
||
}
|
||
}
|
||
|
||
op_right = operator (&op_chars);
|
||
|
||
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. */
|
||
#ifdef md_optimize_expr
|
||
if (md_optimize_expr (resultP, op_left, &right))
|
||
{
|
||
/* Skip. */
|
||
;
|
||
}
|
||
else
|
||
#endif
|
||
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 (rightseg)
|
||
|| right.X_add_symbol == resultP->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;
|
||
if (retval == rightseg && SEG_NORMAL (retval))
|
||
{
|
||
retval = absolute_section;
|
||
rightseg = absolute_section;
|
||
}
|
||
}
|
||
}
|
||
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;
|
||
}
|
||
|
||
if (retval != rightseg)
|
||
{
|
||
if (! SEG_NORMAL (retval))
|
||
{
|
||
if (retval != undefined_section || SEG_NORMAL (rightseg))
|
||
retval = rightseg;
|
||
}
|
||
else if (SEG_NORMAL (rightseg)
|
||
#ifdef DIFF_EXPR_OK
|
||
&& op_left != O_subtract
|
||
#endif
|
||
)
|
||
as_bad (_("operation combines symbols in different segments"));
|
||
}
|
||
|
||
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;
|
||
}
|
||
|
||
/* 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 (void)
|
||
{
|
||
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 (void)
|
||
{
|
||
expressionS exp;
|
||
operand (&exp);
|
||
return exp.X_add_number;
|
||
}
|