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Diffstat (limited to 'gnu/gas/expr.c')
| -rw-r--r-- | gnu/gas/expr.c | 980 |
1 files changed, 0 insertions, 980 deletions
diff --git a/gnu/gas/expr.c b/gnu/gas/expr.c deleted file mode 100644 index f3a377d350b7..000000000000 --- a/gnu/gas/expr.c +++ /dev/null @@ -1,980 +0,0 @@ -/* expr.c -operands, expressions- - Copyright (C) 1987 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 1, 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, 675 Mass Ave, Cambridge, MA 02139, 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 "as.h" -#include "flonum.h" -#include "read.h" -#include "struc-symbol.h" -#include "expr.h" -#include "obstack.h" -#include "symbols.h" - -static void clean_up_expression(); /* Internal. */ -extern const char EXP_CHARS[]; /* JF hide MD floating pt stuff all the same place */ -extern const char FLT_CHARS[]; - -#ifdef SUN_ASM_SYNTAX -extern int local_label_defined[]; -#endif - -/* - * Build any floating-point literal here. - * Also build any bignum literal here. - */ - -/* LITTLENUM_TYPE generic_buffer [6]; /* JF this is a hack */ -/* 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; - -/* - * Summary of operand(). - * - * in: Input_line_pointer points to 1st char of operand, which may - * be a space. - * - * out: A expressionS. X_seg determines how to understand the rest of the - * expressionS. - * The operand may have been empty: in this case X_seg == SEG_NONE. - * Input_line_pointer -> (next non-blank) char after operand. - * - */ - -static segT -operand (expressionP) - register expressionS * expressionP; -{ - register char c; - register char *name; /* points to name of symbol */ - register struct symbol * symbolP; /* Points to symbol */ - - extern char hex_value[]; /* In hex_value.c */ - char *local_label_name(); - - SKIP_WHITESPACE(); /* Leading whitespace is part of operand. */ - c = * input_line_pointer ++; /* Input_line_pointer -> past char in c. */ - if (isdigit(c)) - { - register valueT number; /* offset or (absolute) value */ - register short int digit; /* value of next digit in current radix */ - /* invented for humans only, hope */ - /* optimising compiler flushes it! */ - register short int radix; /* 8, 10 or 16 */ - /* 0 means we saw start of a floating- */ - /* point constant. */ - register short int maxdig;/* Highest permitted digit value. */ - register int too_many_digits; /* If we see >= this number of */ - /* digits, assume it is a bignum. */ - register char * digit_2; /* -> 2nd digit of number. */ - int small; /* TRUE if fits in 32 bits. */ - - if (c=='0') - { /* non-decimal radix */ - if ((c = * input_line_pointer ++)=='x' || c=='X') - { - c = * input_line_pointer ++; /* read past "0x" or "0X" */ - maxdig = radix = 16; - too_many_digits = 9; - } - else - { - /* If it says '0f' and the line ends or it DOESN'T look like - a floating point #, its a local label ref. DTRT */ - if(c=='f' && (! *input_line_pointer || - (!index("+-.0123456789",*input_line_pointer) && - !index(EXP_CHARS,*input_line_pointer)))) - { - maxdig = radix = 10; - too_many_digits = 11; - c='0'; - input_line_pointer-=2; - } - else if (c && index (FLT_CHARS,c)) - { - radix = 0; /* Start of floating-point constant. */ - /* input_line_pointer -> 1st char of number. */ - expressionP -> X_add_number = - (isupper(c) ? tolower(c) : c); - } - else - { /* By elimination, assume octal radix. */ - radix = 8; - maxdig = 10; /* Un*x sux. Compatibility. */ - too_many_digits = 11; - } - } - /* c == char after "0" or "0x" or "0X" or "0e" etc.*/ - } - else - { - maxdig = radix = 10; - too_many_digits = 11; - } - if (radix) - { /* Fixed-point integer constant. */ - /* 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. - */ - digit_2 = 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 - digit_2 < too_many_digits; - 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 int carry; - - leader = generic_bignum; - generic_bignum [0] = 0; - generic_bignum [1] = 0; - /* We could just use digit_2, but lets be mnemonic. */ - input_line_pointer = -- digit_2; /* -> 1st digit. */ - c = *input_line_pointer ++; - for (; (carry = hex_value [c]) < maxdig; c = * input_line_pointer ++) - { - for (pointer = generic_bignum; - pointer <= leader; - pointer ++) - { - long int 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( BITS_PER_INT == 32 ); - know( LITTLENUM_NUMBER_OF_BITS == 16 ); - /* Hence the constant "2" in the next line. */ - if (leader < generic_bignum + 2) - { /* Will fit into 32 bits. */ - number = - ( (generic_bignum [1] & LITTLENUM_MASK) << LITTLENUM_NUMBER_OF_BITS ) - | (generic_bignum [0] & LITTLENUM_MASK); - small = TRUE; - } - else - { - number = leader - generic_bignum + 1; /* Number of littlenums in the bignum. */ - } - } - 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 (number<10) - { -#ifdef SUN_ASM_SYNTAX - if (c=='b' || (c=='$' && local_label_defined[number])) -#else - if (c=='b') -#endif - { - /* - * Backward ref to local label. - * Because it is backward, expect it to be DEFINED. - */ - /* - * Construct a local label. - */ - name = local_label_name ((int)number, 0); - if ( (symbolP = symbol_table_lookup(name)) /* seen before */ - && (symbolP -> sy_type & N_TYPE) != N_UNDF /* symbol is defined: OK */ - ) - { /* Expected path: symbol defined. */ - /* Local labels are never absolute. Don't waste time checking absoluteness. */ - know( (symbolP -> sy_type & N_TYPE) == N_DATA - || (symbolP -> sy_type & N_TYPE) == N_TEXT ); - expressionP -> X_add_symbol = symbolP; - expressionP -> X_add_number = 0; - expressionP -> X_seg = N_TYPE_seg [symbolP -> sy_type]; - } - else - { /* Either not seen or not defined. */ - as_warn( "Backw. ref to unknown label \"%d:\", 0 assumed.", - number - ); - expressionP -> X_add_number = 0; - expressionP -> X_seg = SEG_ABSOLUTE; - } - } - else - { -#ifdef SUN_ASM_SYNTAX - if (c=='f' || (c=='$' && !local_label_defined[number])) -#else - if (c=='f') -#endif - { - /* - * Forward reference. Expect symbol to be undefined or - * unknown. Undefined: seen it before. Unknown: never seen - * it in this pass. - * 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 = local_label_name ((int)number, 1); - if ( symbolP = symbol_table_lookup( name )) - { - /* We have no need to check symbol properties. */ - know( (symbolP -> sy_type & N_TYPE) == N_UNDF - || (symbolP -> sy_type & N_TYPE) == N_DATA - || (symbolP -> sy_type & N_TYPE) == N_TEXT); - } - else - { - symbolP = symbol_new (name, N_UNDF, 0,0,0, & zero_address_frag); - symbol_table_insert (symbolP); - } - expressionP -> X_add_symbol = symbolP; - expressionP -> X_seg = SEG_UNKNOWN; - expressionP -> X_subtract_symbol = NULL; - expressionP -> X_add_number = 0; - } - else - { /* Really a number, not a local label. */ - expressionP -> X_add_number = number; - expressionP -> X_seg = SEG_ABSOLUTE; - input_line_pointer --; /* Restore following character. */ - } /* if (c=='f') */ - } /* if (c=='b') */ - } - else - { /* Really a number. */ - expressionP -> X_add_number = number; - expressionP -> X_seg = SEG_ABSOLUTE; - input_line_pointer --; /* Restore following character. */ - } /* if (number<10) */ - } - else - { - expressionP -> X_add_number = number; - expressionP -> X_seg = SEG_BIG; - input_line_pointer --; /* -> char following number. */ - } /* if (small) */ - } /* (If integer constant) */ - else - { /* 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_warn( "Bad floating-point constant: exponent overflow, probably assembling junk" ); - } - else - { - as_warn( "Bad floating-point constant: unknown error code=%d.", error_code); - } - } - expressionP -> X_seg = SEG_BIG; - /* input_line_pointer -> just after constant, */ - /* which may point to whitespace. */ - know( expressionP -> X_add_number < 0 ); /* < 0 means "floating point". */ - } /* if (not floating-point constant) */ - } - else if(c=='.' && !is_part_of_name(*input_line_pointer)) { - extern struct obstack frags; - - /* - JF: '.' is pseudo symbol with value of current location in current - segment. . . - */ - symbolP = symbol_new("L0\001", - (unsigned char)(seg_N_TYPE[(int)now_seg]), - 0, - 0, - (valueT)(obstack_next_free(&frags)-frag_now->fr_literal), - frag_now); - expressionP->X_add_number=0; - expressionP->X_add_symbol=symbolP; - expressionP->X_seg = now_seg; - - } else 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. - */ - name = -- input_line_pointer; - c = get_symbol_end(); - symbolP = symbol_table_lookup(name); - if (symbolP) - { - /* - * If we have an absolute symbol, then we know it's value now. - */ - register segT seg; - - seg = N_TYPE_seg [(int) symbolP -> sy_type & N_TYPE]; - if ((expressionP -> X_seg = seg) == SEG_ABSOLUTE ) - { - expressionP -> X_add_number = symbolP -> sy_value; - } - else - { - expressionP -> X_add_number = 0; - expressionP -> X_add_symbol = symbolP; - } - } - else - { - expressionP -> X_add_symbol - = symbolP - = symbol_new (name, N_UNDF, 0,0,0, & zero_address_frag); - - expressionP -> X_add_number = 0; - expressionP -> X_seg = SEG_UNKNOWN; - symbol_table_insert (symbolP); - } - * input_line_pointer = c; - expressionP -> X_subtract_symbol = NULL; - } - else if (c=='(')/* didn't begin with digit & not a name */ - { - (void)expression( expressionP ); - /* Expression() will pass trailing whitespace */ - if ( * input_line_pointer ++ != ')' ) - { - as_warn( "Missing ')' assumed"); - input_line_pointer --; - } - /* here with input_line_pointer -> char after "(...)" */ - } - else if ( c=='~' || c=='-' ) - { /* unary operator: hope for SEG_ABSOLUTE */ - switch(operand (expressionP)) { - case SEG_ABSOLUTE: - /* 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. - */ - } - else - { - expressionP -> X_add_number = ~ expressionP -> X_add_number; - } - break; - - case SEG_TEXT: - case SEG_DATA: - case SEG_BSS: - case SEG_PASS1: - case SEG_UNKNOWN: - if(c=='-') { /* JF I hope this hack works */ - expressionP->X_subtract_symbol=expressionP->X_add_symbol; - expressionP->X_add_symbol=0; - expressionP->X_seg=SEG_DIFFERENCE; - break; - } - default: /* unary on non-absolute is unsuported */ - as_warn("Unary operator %c ignored because bad operand follows", c); - break; - /* Expression undisturbed from operand(). */ - } - } - else if (c=='\'') - { -/* - * 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_add_number = * input_line_pointer ++; - expressionP -> X_seg = SEG_ABSOLUTE; - } - else - { - /* can't imagine any other kind of operand */ - expressionP -> X_seg = SEG_NONE; - input_line_pointer --; - } -/* - * 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 != ' ' ); - return (expressionP -> X_seg); -} /* operand */ - -/* Internal. Simplify a struct expression for use by expr() */ - -/* - * In: address of a expressionS. - * The X_seg field of the expressionS may only take certain values. - * Now, we permit SEG_PASS1 to make code smaller & faster. - * Elsewise we waste time special-case testing. Sigh. Ditto SEG_NONE. - * Out: expressionS may have been modified: - * 'foo-foo' symbol references cancelled to 0, - * which changes X_seg from SEG_DIFFERENCE to SEG_ABSOLUTE; - * Unused fields zeroed to help expr(). - */ - -static void -clean_up_expression (expressionP) - register expressionS * expressionP; -{ - switch (expressionP -> X_seg) - { - case SEG_NONE: - case SEG_PASS1: - expressionP -> X_add_symbol = NULL; - expressionP -> X_subtract_symbol = NULL; - expressionP -> X_add_number = 0; - break; - - case SEG_BIG: - case SEG_ABSOLUTE: - expressionP -> X_subtract_symbol = NULL; - expressionP -> X_add_symbol = NULL; - break; - - case SEG_TEXT: - case SEG_DATA: - case SEG_BSS: - case SEG_UNKNOWN: - expressionP -> X_subtract_symbol = NULL; - break; - - case SEG_DIFFERENCE: - /* - * It does not hurt to 'cancel' NULL==NULL - * when comparing symbols for 'eq'ness. - * It is faster to re-cancel them to NULL - * than to check for this special case. - */ - if (expressionP -> X_subtract_symbol == expressionP -> X_add_symbol - || ( expressionP->X_subtract_symbol - && expressionP->X_add_symbol - && expressionP->X_subtract_symbol->sy_frag==expressionP->X_add_symbol->sy_frag - && expressionP->X_subtract_symbol->sy_value==expressionP->X_add_symbol->sy_value)) - { - expressionP -> X_subtract_symbol = NULL; - expressionP -> X_add_symbol = NULL; - expressionP -> X_seg = SEG_ABSOLUTE; - } - break; - - default: - BAD_CASE( expressionP -> X_seg); - break; - } -} - -/* - * expr_part () - * - * Internal. Made a function because this code is used in 2 places. - * Generate error or correct X_?????_symbol of expressionS. - */ - -/* - * symbol_1 += symbol_2 ... well ... sort of. - */ - -static segT -expr_part (symbol_1_PP, symbol_2_P) - struct symbol ** symbol_1_PP; - struct symbol * symbol_2_P; -{ - segT return_value; - - know( (* symbol_1_PP) == NULL - || ((* symbol_1_PP) -> sy_type & N_TYPE) == N_TEXT - || ((* symbol_1_PP) -> sy_type & N_TYPE) == N_DATA - || ((* symbol_1_PP) -> sy_type & N_TYPE) == N_BSS - || ((* symbol_1_PP) -> sy_type & N_TYPE) == N_UNDF - ); - know( symbol_2_P == NULL - || (symbol_2_P -> sy_type & N_TYPE) == N_TEXT - || (symbol_2_P -> sy_type & N_TYPE) == N_DATA - || (symbol_2_P -> sy_type & N_TYPE) == N_BSS - || (symbol_2_P -> sy_type & N_TYPE) == N_UNDF - ); - if (* symbol_1_PP) - { - if (((* symbol_1_PP) -> sy_type & N_TYPE) == N_UNDF) - { - if (symbol_2_P) - { - return_value = SEG_PASS1; - * symbol_1_PP = NULL; - } - else - { - know( ((* symbol_1_PP) -> sy_type & N_TYPE) == N_UNDF) - return_value = SEG_UNKNOWN; - } - } - else - { - if (symbol_2_P) - { - if ((symbol_2_P -> sy_type & N_TYPE) == N_UNDF) - { - * symbol_1_PP = NULL; - return_value = SEG_PASS1; - } - else - { - /* {seg1} - {seg2} */ - as_warn( "Expression too complex, 2 symbols forgotten: \"%s\" \"%s\"", - (* symbol_1_PP) -> sy_name, symbol_2_P -> sy_name ); - * symbol_1_PP = NULL; - return_value = SEG_ABSOLUTE; - } - } - else - { - return_value = N_TYPE_seg [(* symbol_1_PP) -> sy_type & N_TYPE]; - } - } - } - else - { /* (* symbol_1_PP) == NULL */ - if (symbol_2_P) - { - * symbol_1_PP = symbol_2_P; - return_value = N_TYPE_seg [(symbol_2_P) -> sy_type & N_TYPE]; - } - else - { - * symbol_1_PP = NULL; - return_value = SEG_ABSOLUTE; - } - } - know( return_value == SEG_ABSOLUTE - || return_value == SEG_TEXT - || return_value == SEG_DATA - || return_value == SEG_BSS - || return_value == SEG_UNKNOWN - || return_value == SEG_PASS1 - ); - know( (* symbol_1_PP) == NULL - || ((* symbol_1_PP) -> sy_type & N_TYPE) == seg_N_TYPE [(int) return_value] ); - return (return_value); -} /* expr_part() */ - -/* 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. - */ - -typedef enum -{ -O_illegal, /* (0) what we get for illegal op */ - -O_multiply, /* (1) * */ -O_divide, /* (2) / */ -O_modulus, /* (3) % */ -O_left_shift, /* (4) < */ -O_right_shift, /* (5) > */ -O_bit_inclusive_or, /* (6) | */ -O_bit_or_not, /* (7) ! */ -O_bit_exclusive_or, /* (8) ^ */ -O_bit_and, /* (9) & */ -O_add, /* (10) + */ -O_subtract /* (11) - */ -} -operatorT; - -#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_left_shift, __, O_right_shift, __, -__, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, -__, __, __, __, __, __, O_bit_exclusive_or, __, -__, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, -__, __, __, __, O_bit_inclusive_or, __, __, __, - -__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, -__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __ -}; - - -/* - * Rank Examples - * 0 operand, (expression) - * 1 + - - * 2 & ^ ! | - * 3 * / % < > - */ -typedef char operator_rankT; -static const operator_rankT -op_rank [] = { 0, 3, 3, 3, 3, 3, 2, 2, 2, 2, 1, 1 }; - -segT /* Return resultP -> X_seg. */ -expr (rank, resultP) - register operator_rankT rank; /* Larger # is higher rank. */ - register expressionS * resultP; /* Deliver result here. */ -{ - expressionS right; - register operatorT op_left; - register char c_left; /* 1st operator character. */ - register operatorT op_right; - register char c_right; - - know( rank >= 0 ); - (void)operand (resultP); - know( * input_line_pointer != ' ' ); /* Operand() gobbles spaces. */ - c_left = * input_line_pointer; /* Potential operator character. */ - op_left = op_encoding [c_left]; - while (op_left != O_illegal && op_rank [(int) op_left] > rank) - { - input_line_pointer ++; /* -> after 1st character of operator. */ - /* Operators "<<" and ">>" have 2 characters. */ - if (* input_line_pointer == c_left && (c_left == '<' || c_left == '>') ) - { - input_line_pointer ++; - } /* -> after operator. */ - if (SEG_NONE == expr (op_rank[(int) op_left], &right)) - { - as_warn("Missing operand value assumed absolute 0."); - resultP -> X_add_number = 0; - resultP -> X_subtract_symbol = NULL; - resultP -> X_add_symbol = NULL; - resultP -> X_seg = SEG_ABSOLUTE; - } - know( * input_line_pointer != ' ' ); - c_right = * input_line_pointer; - op_right = op_encoding [c_right]; - if (* input_line_pointer == c_right && (c_right == '<' || c_right == '>') ) - { - input_line_pointer ++; - } /* -> after operator. */ - know( (int) op_right == 0 - || op_rank [(int) op_right] <= op_rank[(int) op_left] ); - /* input_line_pointer -> after right-hand quantity. */ - /* left-hand quantity in resultP */ - /* right-hand quantity in right. */ - /* operator in op_left. */ - if ( resultP -> X_seg == SEG_PASS1 || right . X_seg == SEG_PASS1 ) - { - resultP -> X_seg = SEG_PASS1; - } - else - { - if ( resultP -> X_seg == SEG_BIG ) - { - as_warn( "Left operand of %c is a %s. Integer 0 assumed.", - c_left, resultP -> X_add_number > 0 ? "bignum" : "float"); - resultP -> X_seg = SEG_ABSOLUTE; - resultP -> X_add_symbol = 0; - resultP -> X_subtract_symbol = 0; - resultP -> X_add_number = 0; - } - if ( right . X_seg == SEG_BIG ) - { - as_warn( "Right operand of %c is a %s. Integer 0 assumed.", - c_left, right . X_add_number > 0 ? "bignum" : "float"); - right . X_seg = SEG_ABSOLUTE; - right . X_add_symbol = 0; - right . X_subtract_symbol = 0; - right . X_add_number = 0; - } - if ( op_left == O_subtract ) - { - /* - * Convert - into + by exchanging symbols and negating number. - * I know -infinity can't be negated in 2's complement: - * but then it can't be subtracted either. This trick - * does not cause any further inaccuracy. - */ - - register struct symbol * symbolP; - - right . X_add_number = - right . X_add_number; - symbolP = right . X_add_symbol; - right . X_add_symbol = right . X_subtract_symbol; - right . X_subtract_symbol = symbolP; - if (symbolP) - { - right . X_seg = SEG_DIFFERENCE; - } - op_left = O_add; - } - - if ( op_left == O_add ) - { - segT seg1; - segT seg2; - - know( resultP -> X_seg == SEG_DATA - || resultP -> X_seg == SEG_TEXT - || resultP -> X_seg == SEG_BSS - || resultP -> X_seg == SEG_UNKNOWN - || resultP -> X_seg == SEG_DIFFERENCE - || resultP -> X_seg == SEG_ABSOLUTE - || resultP -> X_seg == SEG_PASS1 - ); - know( right . X_seg == SEG_DATA - || right . X_seg == SEG_TEXT - || right . X_seg == SEG_BSS - || right . X_seg == SEG_UNKNOWN - || right . X_seg == SEG_DIFFERENCE - || right . X_seg == SEG_ABSOLUTE - || right . X_seg == SEG_PASS1 - ); - - clean_up_expression (& right); - clean_up_expression (resultP); - - seg1 = expr_part (& resultP -> X_add_symbol, right . X_add_symbol); - seg2 = expr_part (& resultP -> X_subtract_symbol, right . X_subtract_symbol); - if (seg1 == SEG_PASS1 || seg2 == SEG_PASS1) { - need_pass_2 = TRUE; - resultP -> X_seg = SEG_PASS1; - } else if (seg2 == SEG_ABSOLUTE) - resultP -> X_seg = seg1; - else if ( seg1 != SEG_UNKNOWN - && seg1 != SEG_ABSOLUTE - && seg2 != SEG_UNKNOWN - && seg1 != seg2) { - know( seg2 != SEG_ABSOLUTE ); - know( resultP -> X_subtract_symbol ); - - know( seg1 == SEG_TEXT || seg1 == SEG_DATA || seg1== SEG_BSS ); - know( seg2 == SEG_TEXT || seg2 == SEG_DATA || seg2== SEG_BSS ); - know( resultP -> X_add_symbol ); - know( resultP -> X_subtract_symbol ); - as_warn("Expression too complex: forgetting %s - %s", - resultP -> X_add_symbol -> sy_name, - resultP -> X_subtract_symbol -> sy_name); - resultP -> X_seg = SEG_ABSOLUTE; - /* Clean_up_expression() will do the rest. */ - } else - resultP -> X_seg = SEG_DIFFERENCE; - - resultP -> X_add_number += right . X_add_number; - clean_up_expression (resultP); - } - else - { /* Not +. */ - if ( resultP -> X_seg == SEG_UNKNOWN || right . X_seg == SEG_UNKNOWN ) - { - resultP -> X_seg = SEG_PASS1; - need_pass_2 = TRUE; - } - else - { - resultP -> X_subtract_symbol = NULL; - resultP -> X_add_symbol = NULL; - /* Will be SEG_ABSOLUTE. */ - if ( resultP -> X_seg != SEG_ABSOLUTE || right . X_seg != SEG_ABSOLUTE ) - { - as_warn( "Relocation error. Absolute 0 assumed."); - resultP -> X_seg = SEG_ABSOLUTE; - resultP -> X_add_number = 0; - } - else - { - switch ( op_left ) - { - case O_bit_inclusive_or: - resultP -> X_add_number |= right . X_add_number; - break; - - case O_modulus: - if (right . X_add_number) - { - resultP -> X_add_number %= right . X_add_number; - } - else - { - as_warn( "Division by 0. 0 assumed." ); - resultP -> X_add_number = 0; - } - break; - - case O_bit_and: - resultP -> X_add_number &= right . X_add_number; - break; - - case O_multiply: - resultP -> X_add_number *= right . X_add_number; - break; - - case O_divide: - if (right . X_add_number) - { - resultP -> X_add_number /= right . X_add_number; - } - else - { - as_warn( "Division by 0. 0 assumed." ); - resultP -> X_add_number = 0; - } - break; - - case O_left_shift: - resultP -> X_add_number <<= right . X_add_number; - break; - - case O_right_shift: - resultP -> X_add_number >>= right . X_add_number; - break; - - case O_bit_exclusive_or: - resultP -> X_add_number ^= right . X_add_number; - break; - - case O_bit_or_not: - resultP -> X_add_number |= ~ right . X_add_number; - break; - - default: - BAD_CASE( op_left ); - break; - } /* switch(operator) */ - } - } /* If we have to force need_pass_2. */ - } /* If operator was +. */ - } /* If we didn't set need_pass_2. */ - op_left = op_right; - } /* While next operator is >= this rank. */ - return (resultP -> X_seg); -} - -/* - * 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() -{ - register char c; - - while ( is_part_of_name( c = * input_line_pointer ++ ) ) - ; - * -- input_line_pointer = 0; - return (c); -} - -/* end: expr.c */ |