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Diffstat (limited to 'binutils-2.25/gas/expr.c')
| -rw-r--r-- | binutils-2.25/gas/expr.c | 2367 |
1 files changed, 2367 insertions, 0 deletions
diff --git a/binutils-2.25/gas/expr.c b/binutils-2.25/gas/expr.c new file mode 100644 index 00000000..c4b2b756 --- /dev/null +++ b/binutils-2.25/gas/expr.c @@ -0,0 +1,2367 @@ +/* expr.c -operands, expressions- + Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, + 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010, 2011, + 2012 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 3, 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, 51 Franklin Street - Fifth Floor, Boston, MA + 02110-1301, 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. */ + +#define min(a, b) ((a) < (b) ? (a) : (b)) + +#include "as.h" +#include "safe-ctype.h" +#include "obstack.h" + +#ifdef HAVE_LIMITS_H +#include <limits.h> +#endif +#ifndef CHAR_BIT +#define CHAR_BIT 8 +#endif + +static void floating_constant (expressionS * expressionP); +static valueT generic_bignum_to_int32 (void); +#ifdef BFD64 +static valueT generic_bignum_to_int64 (void); +#endif +static void integer_constant (int radix, expressionS * expressionP); +static void mri_char_constant (expressionS *); +static void clean_up_expression (expressionS * expressionP); +static segT operand (expressionS *, enum expr_mode); +static operatorT operatorf (int *); + +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 (expressionS *expressionP) +{ + expressionS zero; + 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")); + else + as_bad (_("floating point number invalid")); + zero.X_op = O_constant; + zero.X_add_number = 0; + zero.X_unsigned = 0; + zero.X_extrabit = 0; + clean_up_expression (&zero); + expressionP = &zero; + } + + /* 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_LABEL_NAME, + (expressionP->X_op == O_constant + ? absolute_section + : expressionP->X_op == O_register + ? reg_section + : expr_section), + 0, &zero_address_frag); + symbol_set_value_expression (symbolP, expressionP); + + if (expressionP->X_op == O_constant) + resolve_symbol_value (symbolP); + + 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 (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 (offsetT value) +{ + expressionS e; + + e.X_op = O_constant; + e.X_add_number = value; + e.X_unsigned = 1; + e.X_extrabit = 0; + return make_expr_symbol (&e); +} + +/* Build an expression for the current location ('.'). */ + +symbolS * +expr_build_dot (void) +{ + expressionS e; + + current_location (&e); + return symbol_clone_if_forward_ref (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. */ +}; + + +static void +floating_constant (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")); + } + 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 (void) +{ + 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 (void) +{ + 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 (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 ((NUMBERS_WITH_SUFFIX || 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 (*suffix); suffix++) + { + if (*suffix == 'e' || *suffix == 'E') + flt = 1; + } + + if (suffix == input_line_pointer) + { + radix = 10; + suffix = NULL; + } + else + { + c = *--suffix; + c = TOUPPER (c); + /* If we have both NUMBERS_WITH_SUFFIX and LOCAL_LABELS_FB, + we distinguish between 'B' and 'b'. This is the case for + Z80. */ + if ((NUMBERS_WITH_SUFFIX && LOCAL_LABELS_FB ? *suffix : c) == 'B') + radix = 2; + else if (c == 'D') + radix = 10; + else if (c == 'O' || c == 'Q') + radix = 8; + else if (c == 'H') + radix = 16; + else if (suffix[1] == '.' || c == 'E' || flt) + { + floating_constant (expressionP); + return; + } + else + { + radix = 10; + suffix = NULL; + } + } + } + + switch (radix) + { + case 2: + maxdig = 2; + too_many_digits = valuesize + 1; + break; + case 8: + maxdig = radix = 8; + too_many_digits = (valuesize + 2) / 3 + 1; + break; + case 16: + maxdig = radix = 16; + too_many_digits = (valuesize + 3) / 4 + 1; + break; + case 10: + maxdig = radix = 10; + too_many_digits = (valuesize + 11) / 4; /* Very rough. */ + } +#undef valuesize + start = input_line_pointer; + c = *input_line_pointer++; + for (number = 0; + (digit = hex_value (c)) < maxdig; + c = *input_line_pointer++) + { + number = number * radix + digit; + } + /* c contains character after number. */ + /* input_line_pointer->char after c. */ + small = (input_line_pointer - start - 1) < too_many_digits; + + if (radix == 16 && c == '_') + { + /* This is literal of the form 0x333_0_12345678_1. + This example is equivalent to 0x00000333000000001234567800000001. */ + + int num_little_digits = 0; + int i; + input_line_pointer = start; /* -> 1st digit. */ + + know (LITTLENUM_NUMBER_OF_BITS == 16); + + for (c = '_'; c == '_'; num_little_digits += 2) + { + + /* Convert one 64-bit word. */ + int ndigit = 0; + number = 0; + for (c = *input_line_pointer++; + (digit = hex_value (c)) < maxdig; + c = *(input_line_pointer++)) + { + number = number * radix + digit; + ndigit++; + } + + /* Check for 8 digit per word max. */ + if (ndigit > 8) + as_bad (_("a bignum with underscores may not have more than 8 hex digits in any word")); + + /* Add this chunk to the bignum. + Shift things down 2 little digits. */ + know (LITTLENUM_NUMBER_OF_BITS == 16); + for (i = min (num_little_digits + 1, SIZE_OF_LARGE_NUMBER - 1); + i >= 2; + i--) + generic_bignum[i] = generic_bignum[i - 2]; + + /* Add the new digits as the least significant new ones. */ + generic_bignum[0] = number & 0xffffffff; + generic_bignum[1] = number >> 16; + } + + /* Again, c is char after number, input_line_pointer->after c. */ + + if (num_little_digits > SIZE_OF_LARGE_NUMBER - 1) + num_little_digits = SIZE_OF_LARGE_NUMBER - 1; + + gas_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 of littlenums in the bignum. */ + number = num_little_digits; + } + } + 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 of littlenums in the bignum. */ + number = leader - generic_bignum + 1; + } + } + + if ((NUMBERS_WITH_SUFFIX || 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 (_("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; + 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 `.'. */ + +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 = &dot_symbol; + 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, enum expr_mode mode) +{ + 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; + expressionP->X_extrabit = 0; + + /* 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; + +#ifndef NEED_INDEX_OPERATOR + case '[': +# ifdef md_need_index_operator + if (md_need_index_operator()) + goto de_fault; +# endif + /* FALLTHROUGH */ +#endif + case '(': + /* Didn't begin with digit & not a name. */ + segment = expr (0, expressionP, mode); + /* expression () will pass trailing whitespace. */ + if ((c == '(' && *input_line_pointer != ')') + || (c == '[' && *input_line_pointer != ']')) + 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; + +#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 '-': + case '+': + { +#ifdef md_operator + unary: +#endif + operand (expressionP, mode); + 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; + if (expressionP->X_add_number) + expressionP->X_extrabit ^= 1; + } + else if (c == '~' || c == '"') + expressionP->X_add_number = ~ expressionP->X_add_number; + else if (c == '!') + 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_big + && expressionP->X_add_number > 0) + { + int i; + + if (c == '~' || c == '-') + { + for (i = 0; i < expressionP->X_add_number; ++i) + generic_bignum[i] = ~generic_bignum[i]; + + /* Extend the bignum to at least the size of .octa. */ + if (expressionP->X_add_number < SIZE_OF_LARGE_NUMBER) + { + expressionP->X_add_number = SIZE_OF_LARGE_NUMBER; + for (; i < expressionP->X_add_number; ++i) + generic_bignum[i] = ~(LITTLENUM_TYPE) 0; + } + + if (c == '-') + for (i = 0; i < expressionP->X_add_number; ++i) + { + generic_bignum[i] += 1; + if (generic_bignum[i]) + break; + } + } + else if (c == '!') + { + for (i = 0; i < expressionP->X_add_number; ++i) + if (generic_bignum[i] != 0) + break; + expressionP->X_add_number = i >= expressionP->X_add_number; + expressionP->X_op = O_constant; + expressionP->X_unsigned = 1; + expressionP->X_extrabit = 0; + } + } + else if (expressionP->X_op != O_illegal + && expressionP->X_op != O_absent) + { + if (c != '+') + { + 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 (DOLLAR_AMBIGU && hex_p (*input_line_pointer)) + { + /* In MRI mode and on Z80, '$' 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: +#if defined(md_need_index_operator) || defined(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_operator + { + operatorT op = md_operator (name, 1, &c); + + switch (op) + { + case O_uminus: + *input_line_pointer = c; + c = '-'; + goto unary; + case O_bit_not: + *input_line_pointer = c; + c = '~'; + goto unary; + case O_logical_not: + *input_line_pointer = c; + c = '!'; + goto unary; + case O_illegal: + as_bad (_("invalid use of operator \"%s\""), name); + break; + default: + break; + } + if (op != O_absent && op != O_illegal) + { + *input_line_pointer = c; + expr (9, expressionP, mode); + expressionP->X_add_symbol = make_expr_symbol (expressionP); + expressionP->X_op_symbol = NULL; + expressionP->X_add_number = 0; + expressionP->X_op = op; + break; + } + } +#endif + +#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, mode, &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 (mode != expr_defer + && segment == absolute_section + && !S_FORCE_RELOC (symbolP, 0)) + { + expressionP->X_op = O_constant; + expressionP->X_add_number = S_GET_VALUE (symbolP); + } + else if (mode != expr_defer && 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 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); + + if (mode != expr_defer) + { + expressionP->X_add_symbol + = symbol_clone_if_forward_ref (expressionP->X_add_symbol); + expressionP->X_op_symbol + = symbol_clone_if_forward_ref (expressionP->X_op_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 +#ifndef O_SINGLE_EQ +#define O_SINGLE_EQ O_illegal +#endif + +/* 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_SINGLE_EQ, 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[O_max] = { + 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 */ +}; + +/* 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; + } +} + +void +expr_set_rank (operatorT op, operator_rankT rank) +{ + gas_assert (op >= O_md1 && op < ARRAY_SIZE (op_rank)); + op_rank[op] = rank; +} + +/* 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; + gas_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 +operatorf (int *num_chars) +{ + int c; + operatorT ret; + + c = *input_line_pointer & 0xff; + *num_chars = 1; + + if (is_end_of_line[c]) + return O_illegal; + +#ifdef md_operator + if (is_name_beginner (c)) + { + char *name = input_line_pointer; + char ec = get_symbol_end (); + + ret = md_operator (name, 2, &ec); + switch (ret) + { + case O_absent: + *input_line_pointer = ec; + input_line_pointer = name; + break; + case O_uminus: + case O_bit_not: + case O_logical_not: + as_bad (_("invalid use of operator \"%s\""), name); + ret = O_illegal; + /* FALLTHROUGH */ + default: + *input_line_pointer = ec; + *num_chars = input_line_pointer - name; + input_line_pointer = name; + return ret; + } + } +#endif + + switch (c) + { + default: + ret = op_encoding[c]; +#ifdef md_operator + if (ret == O_illegal) + { + char *start = input_line_pointer; + + ret = md_operator (NULL, 2, NULL); + if (ret != O_illegal) + *num_chars = input_line_pointer - start; + input_line_pointer = start; + } +#endif + return ret; + + case '+': + case '-': + 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; + } + *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 '!': + switch (input_line_pointer[1]) + { + case '!': + /* We accept !! as equivalent to ^ for MRI compatibility. */ + *num_chars = 2; + return O_bit_exclusive_or; + case '=': + /* We accept != as equivalent to <>. */ + *num_chars = 2; + return O_ne; + default: + if (flag_m68k_mri) + return O_bit_inclusive_or; + return op_encoding[c]; + } + + 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 */ +} + +/* Implement "word-size + 1 bit" addition for + {resultP->X_extrabit:resultP->X_add_number} + {rhs_highbit:amount}. This + is used so that the full range of unsigned word values and the full range of + signed word values can be represented in an O_constant expression, which is + useful e.g. for .sleb128 directives. */ + +void +add_to_result (expressionS *resultP, offsetT amount, int rhs_highbit) +{ + valueT ures = resultP->X_add_number; + valueT uamount = amount; + + resultP->X_add_number += amount; + + resultP->X_extrabit ^= rhs_highbit; + + if (ures + uamount < ures) + resultP->X_extrabit ^= 1; +} + +/* Similarly, for subtraction. */ + +void +subtract_from_result (expressionS *resultP, offsetT amount, int rhs_highbit) +{ + valueT ures = resultP->X_add_number; + valueT uamount = amount; + + resultP->X_add_number -= amount; + + resultP->X_extrabit ^= rhs_highbit; + + if (ures < uamount) + resultP->X_extrabit ^= 1; +} + +/* Parse an expression. */ + +segT +expr (int rankarg, /* Larger # is higher rank. */ + expressionS *resultP, /* Deliver result here. */ + enum expr_mode mode /* Controls behavior. */) +{ + operator_rankT rank = (operator_rankT) rankarg; + segT retval; + expressionS right; + operatorT op_left; + operatorT op_right; + int op_chars; + + know (rankarg >= 0); + + /* Save the value of dot for the fixup code. */ + if (rank == 0) + { + dot_value = frag_now_fix (); + dot_frag = frag_now; + } + + retval = operand (resultP, mode); + + /* operand () gobbles spaces. */ + know (*input_line_pointer != ' '); + + op_left = operatorf (&op_chars); + while (op_left != O_illegal && op_rank[(int) op_left] > rank) + { + segT rightseg; + offsetT frag_off; + + input_line_pointer += op_chars; /* -> after operator. */ + + right.X_md = 0; + rightseg = expr (op_rank[(int) op_left], &right, mode); + 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 = operatorf (&op_chars); + + know (op_right == O_illegal || op_left == O_index + || op_rank[(int) op_right] <= op_rank[(int) op_left]); + know ((int) op_left >= (int) O_multiply); +#ifndef md_operator + know ((int) op_left <= (int) O_index); +#else + know ((int) op_left < (int) O_max); +#endif + + /* 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 +#ifndef md_register_arithmetic +# define md_register_arithmetic 1 +#endif + if (op_left == O_add && right.X_op == O_constant + && (md_register_arithmetic || resultP->X_op != O_register)) + { + /* X + constant. */ + add_to_result (resultP, right.X_add_number, right.X_extrabit); + } + /* This case comes up in PIC code. */ + else if (op_left == O_subtract + && right.X_op == O_symbol + && resultP->X_op == O_symbol + && retval == rightseg +#ifdef md_allow_local_subtract + && md_allow_local_subtract (resultP, & right, rightseg) +#endif + && ((SEG_NORMAL (rightseg) + && !S_FORCE_RELOC (resultP->X_add_symbol, 0) + && !S_FORCE_RELOC (right.X_add_symbol, 0)) + || right.X_add_symbol == resultP->X_add_symbol) + && frag_offset_fixed_p (symbol_get_frag (resultP->X_add_symbol), + symbol_get_frag (right.X_add_symbol), + &frag_off)) + { + offsetT symval_diff = S_GET_VALUE (resultP->X_add_symbol) + - S_GET_VALUE (right.X_add_symbol); + subtract_from_result (resultP, right.X_add_number, right.X_extrabit); + subtract_from_result (resultP, frag_off / OCTETS_PER_BYTE, 0); + add_to_result (resultP, symval_diff, symval_diff < 0); + resultP->X_op = O_constant; + resultP->X_add_symbol = 0; + } + else if (op_left == O_subtract && right.X_op == O_constant + && (md_register_arithmetic || resultP->X_op != O_register)) + { + /* X - constant. */ + subtract_from_result (resultP, right.X_add_number, right.X_extrabit); + } + else if (op_left == O_add && resultP->X_op == O_constant + && (md_register_arithmetic || right.X_op != O_register)) + { + /* Constant + X. */ + resultP->X_op = right.X_op; + resultP->X_add_symbol = right.X_add_symbol; + resultP->X_op_symbol = right.X_op_symbol; + add_to_result (resultP, right.X_add_number, right.X_extrabit); + 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; + } + if ((valueT) v >= sizeof(valueT) * CHAR_BIT + && (op_left == O_left_shift || op_left == O_right_shift)) + { + as_warn_value_out_of_range (_("shift count"), v, 0, + sizeof(valueT) * CHAR_BIT - 1, + NULL, 0); + resultP->X_add_number = v = 0; + } + switch (op_left) + { + default: goto general; + 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; + /* Constant + constant (O_add) is handled by the + previous if statement for constant + X, so is omitted + here. */ + case O_subtract: + subtract_from_result (resultP, v, 0); + 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) + add_to_result (resultP, right.X_add_number, right.X_extrabit); + else if (op_left == O_subtract) + { + subtract_from_result (resultP, right.X_add_number, + right.X_extrabit); + if (retval == rightseg + && SEG_NORMAL (retval) + && !S_FORCE_RELOC (resultP->X_add_symbol, 0) + && !S_FORCE_RELOC (right.X_add_symbol, 0)) + { + retval = absolute_section; + rightseg = absolute_section; + } + } + } + else + { + general: + /* 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; + resultP->X_extrabit = 0; + } + + if (retval != rightseg) + { + if (retval == undefined_section) + ; + else if (rightseg == undefined_section) + retval = rightseg; + else if (retval == expr_section) + ; + else if (rightseg == expr_section) + retval = rightseg; + else if (retval == reg_section) + ; + else if (rightseg == reg_section) + retval = rightseg; + else if (rightseg == absolute_section) + ; + else if (retval == absolute_section) + retval = rightseg; +#ifdef DIFF_EXPR_OK + else if (op_left == O_subtract) + ; +#endif + else + 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); + + if (rank == 0 && mode == expr_evaluate) + resolve_expression (resultP); + + return resultP->X_op == O_constant ? absolute_section : retval; +} + +/* Resolve an expression without changing any symbols/sub-expressions + used. */ + +int +resolve_expression (expressionS *expressionP) +{ + /* Help out with CSE. */ + valueT final_val = expressionP->X_add_number; + symbolS *add_symbol = expressionP->X_add_symbol; + symbolS *orig_add_symbol = add_symbol; + symbolS *op_symbol = expressionP->X_op_symbol; + operatorT op = expressionP->X_op; + valueT left, right; + segT seg_left, seg_right; + fragS *frag_left, *frag_right; + offsetT frag_off; + + switch (op) + { + default: + return 0; + + case O_constant: + case O_register: + left = 0; + break; + + case O_symbol: + case O_symbol_rva: + if (!snapshot_symbol (&add_symbol, &left, &seg_left, &frag_left)) + return 0; + + break; + + case O_uminus: + case O_bit_not: + case O_logical_not: + if (!snapshot_symbol (&add_symbol, &left, &seg_left, &frag_left)) + return 0; + + if (seg_left != absolute_section) + return 0; + + if (op == O_logical_not) + left = !left; + else if (op == O_uminus) + left = -left; + else + left = ~left; + op = O_constant; + break; + + case O_multiply: + case O_divide: + case O_modulus: + case O_left_shift: + case O_right_shift: + case O_bit_inclusive_or: + case O_bit_or_not: + case O_bit_exclusive_or: + case O_bit_and: + case O_add: + case O_subtract: + case O_eq: + case O_ne: + case O_lt: + case O_le: + case O_ge: + case O_gt: + case O_logical_and: + case O_logical_or: + if (!snapshot_symbol (&add_symbol, &left, &seg_left, &frag_left) + || !snapshot_symbol (&op_symbol, &right, &seg_right, &frag_right)) + return 0; + + /* Simplify addition or subtraction of a constant by folding the + constant into X_add_number. */ + if (op == O_add) + { + if (seg_right == absolute_section) + { + final_val += right; + op = O_symbol; + break; + } + else if (seg_left == absolute_section) + { + final_val += left; + left = right; + seg_left = seg_right; + add_symbol = op_symbol; + orig_add_symbol = expressionP->X_op_symbol; + op = O_symbol; + break; + } + } + else if (op == O_subtract) + { + if (seg_right == absolute_section) + { + final_val -= right; + op = O_symbol; + break; + } + } + + /* Equality and non-equality tests are permitted on anything. + Subtraction, and other comparison operators are permitted if + both operands are in the same section. + Shifts by constant zero are permitted on anything. + Multiplies, bit-ors, and bit-ands with constant zero are + permitted on anything. + Multiplies and divides by constant one are permitted on + anything. + Binary operations with both operands being the same register + or undefined symbol are permitted if the result doesn't depend + on the input value. + Otherwise, both operands must be absolute. We already handled + the case of addition or subtraction of a constant above. */ + frag_off = 0; + if (!(seg_left == absolute_section + && seg_right == absolute_section) + && !(op == O_eq || op == O_ne) + && !((op == O_subtract + || op == O_lt || op == O_le || op == O_ge || op == O_gt) + && seg_left == seg_right + && (finalize_syms + || frag_offset_fixed_p (frag_left, frag_right, &frag_off)) + && (seg_left != reg_section || left == right) + && (seg_left != undefined_section || add_symbol == op_symbol))) + { + if ((seg_left == absolute_section && left == 0) + || (seg_right == absolute_section && right == 0)) + { + if (op == O_bit_exclusive_or || op == O_bit_inclusive_or) + { + if (!(seg_right == absolute_section && right == 0)) + { + seg_left = seg_right; + left = right; + add_symbol = op_symbol; + orig_add_symbol = expressionP->X_op_symbol; + } + op = O_symbol; + break; + } + else if (op == O_left_shift || op == O_right_shift) + { + if (!(seg_left == absolute_section && left == 0)) + { + op = O_symbol; + break; + } + } + else if (op != O_multiply + && op != O_bit_or_not && op != O_bit_and) + return 0; + } + else if (op == O_multiply + && seg_left == absolute_section && left == 1) + { + seg_left = seg_right; + left = right; + add_symbol = op_symbol; + orig_add_symbol = expressionP->X_op_symbol; + op = O_symbol; + break; + } + else if ((op == O_multiply || op == O_divide) + && seg_right == absolute_section && right == 1) + { + op = O_symbol; + break; + } + else if (!(left == right + && ((seg_left == reg_section && seg_right == reg_section) + || (seg_left == undefined_section + && seg_right == undefined_section + && add_symbol == op_symbol)))) + return 0; + else if (op == O_bit_and || op == O_bit_inclusive_or) + { + op = O_symbol; + break; + } + else if (op != O_bit_exclusive_or && op != O_bit_or_not) + return 0; + } + + right += frag_off / OCTETS_PER_BYTE; + switch (op) + { + case O_add: left += right; break; + case O_subtract: left -= right; break; + case O_multiply: left *= right; break; + case O_divide: + if (right == 0) + return 0; + left = (offsetT) left / (offsetT) right; + break; + case O_modulus: + if (right == 0) + return 0; + left = (offsetT) left % (offsetT) right; + break; + case O_left_shift: left <<= right; break; + case O_right_shift: left >>= right; break; + case O_bit_inclusive_or: left |= right; break; + case O_bit_or_not: left |= ~right; break; + case O_bit_exclusive_or: left ^= right; break; + case O_bit_and: left &= right; break; + case O_eq: + case O_ne: + left = (left == right + && seg_left == seg_right + && (finalize_syms || frag_left == frag_right) + && (seg_left != undefined_section + || add_symbol == op_symbol) + ? ~ (valueT) 0 : 0); + if (op == O_ne) + left = ~left; + break; + case O_lt: + left = (offsetT) left < (offsetT) right ? ~ (valueT) 0 : 0; + break; + case O_le: + left = (offsetT) left <= (offsetT) right ? ~ (valueT) 0 : 0; + break; + case O_ge: + left = (offsetT) left >= (offsetT) right ? ~ (valueT) 0 : 0; + break; + case O_gt: + left = (offsetT) left > (offsetT) right ? ~ (valueT) 0 : 0; + break; + case O_logical_and: left = left && right; break; + case O_logical_or: left = left || right; break; + default: abort (); + } + + op = O_constant; + break; + } + + if (op == O_symbol) + { + if (seg_left == absolute_section) + op = O_constant; + else if (seg_left == reg_section && final_val == 0) + op = O_register; + else if (!symbol_same_p (add_symbol, orig_add_symbol)) + final_val += left; + expressionP->X_add_symbol = add_symbol; + } + expressionP->X_op = op; + + if (op == O_constant || op == O_register) + final_val += left; + expressionP->X_add_number = final_val; + + return 1; +} + +/* 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, expr_normal); + return exp.X_add_number; +} |