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+/* expr.c -operands, expressions-
+ Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 96, 97, 1998
+ 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 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);
+ symbolP->sy_value = *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 + 12) / 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 '(':
+ case '[':
+ /* 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)
+ expressionP->X_add_symbol->sy_used = 1;
+
+ 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
+ || ((expressionP->X_op_symbol->sy_frag
+ == expressionP->X_add_symbol->sy_frag)
+ && 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, __,
+ __, __, __, __, __, __, __, __,
+ __, __, __, __, __, __, __, __,
+ __, __, __, __, __, __, __, __,
+ __, __, __, __, __, __, 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 */
+ 8, /* O_uminus */
+ 8, /* O_bit_not */
+ 8, /* O_logical_not */
+ 7, /* O_multiply */
+ 7, /* O_divide */
+ 7, /* O_modulus */
+ 7, /* O_left_shift */
+ 7, /* O_right_shift */
+ 6, /* O_bit_inclusive_or */
+ 6, /* O_bit_or_not */
+ 6, /* O_bit_exclusive_or */
+ 6, /* O_bit_and */
+ 4, /* O_add */
+ 4, /* O_subtract */
+ 3, /* O_eq */
+ 3, /* O_ne */
+ 3, /* O_lt */
+ 3, /* O_le */
+ 3, /* O_ge */
+ 3, /* O_gt */
+ 2, /* O_logical_and */
+ 1 /* O_logical_or */
+};
+
+/* 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 (rank, resultP)
+ operator_rankT rank; /* Larger # is higher rank. */
+ expressionS *resultP; /* Deliver result here. */
+{
+ 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 (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
+ && (right.X_add_symbol->sy_frag
+ == resultP->X_add_symbol->sy_frag)
+ && 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)
+ resultP->X_add_symbol->sy_used = 1;
+
+ 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')
+ ;
+ *--input_line_pointer = 0;
+ return (c);
+}
+
+
+unsigned int
+get_single_number ()
+{
+ expressionS exp;
+ operand (&exp);
+ return exp.X_add_number;
+
+}
+
+/* end of expr.c */