/* atof_generic.c - turn a string of digits into a Flonum
Copyright (C) 1987, 1990, 1991, 1992 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, 675 Mass Ave, Cambridge, MA 02139, USA. */
#endif
#endif
-#ifdef USG
-#define bzero(s,n) memset(s,0,n)
+#ifndef FALSE
+#define FALSE (0)
+#endif
+#ifndef TRUE
+#define TRUE (1)
#endif
-
-/* #define FALSE (0) */
-/* #define TRUE (1) */
/***********************************************************************\
* *
* uses base (radix) 2 *
* this machine uses 2's complement binary integers *
* target flonums use " " " " *
- * target flonums exponents fit in a long *
+ * target flonums exponents fit in a long *
* *
\***********************************************************************/
/*
-
+
Syntax:
-
+
<flonum> ::= <optional-sign> <decimal-number> <optional-exponent>
<optional-sign> ::= '+' | '-' | {empty}
<decimal-number> ::= <integer>
- | <integer> <radix-character>
- | <integer> <radix-character> <integer>
+ | <integer> <radix-character>
+ | <integer> <radix-character> <integer>
| <radix-character> <integer>
<optional-exponent> ::= {empty}
<digit> ::= '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9'
<exponent-character> ::= {one character from "string_of_decimal_exponent_marks"}
<radix-character> ::= {one character from "string_of_decimal_marks"}
-
+
*/
-int /* 0 if OK */
- atof_generic (
- address_of_string_pointer, /* return pointer to just
- AFTER number we read. */
- string_of_decimal_marks, /* At most one per number. */
- string_of_decimal_exponent_marks,
- address_of_generic_floating_point_number)
-char **address_of_string_pointer;
-const char *string_of_decimal_marks;
-const char *string_of_decimal_exponent_marks;
-FLONUM_TYPE *address_of_generic_floating_point_number;
+int
+atof_generic (address_of_string_pointer,
+ string_of_decimal_marks,
+ string_of_decimal_exponent_marks,
+ address_of_generic_floating_point_number)
+ /* return pointer to just AFTER number we read. */
+ char **address_of_string_pointer;
+ /* At most one per number. */
+ const char *string_of_decimal_marks;
+ const char *string_of_decimal_exponent_marks;
+ FLONUM_TYPE *address_of_generic_floating_point_number;
{
- int return_value; /* 0 means OK. */
- char * first_digit;
- /* char *last_digit; JF unused */
- int number_of_digits_before_decimal;
- int number_of_digits_after_decimal;
- long decimal_exponent;
- int number_of_digits_available;
- char digits_sign_char;
-
- /*
- * Scan the input string, abstracting (1)digits (2)decimal mark (3) exponent.
- * It would be simpler to modify the string, but we don't; just to be nice
- * to caller.
- * We need to know how many digits we have, so we can allocate space for
- * the digits' value.
- */
-
- char *p;
- char c;
- int seen_significant_digit;
-
- first_digit = *address_of_string_pointer;
- c = *first_digit;
-
- if (c == '-' || c == '+') {
- digits_sign_char = c;
- first_digit++;
- } else
- digits_sign_char = '+';
-
- if ((first_digit[0] == 'n' || first_digit[0] == 'N')
- && (first_digit[1] == 'a' || first_digit[1] == 'A')
- && (first_digit[2] == 'n' || first_digit[2] == 'N')) {
- address_of_generic_floating_point_number->sign = 0;
- address_of_generic_floating_point_number->exponent = 0;
- address_of_generic_floating_point_number->leader =
- address_of_generic_floating_point_number->low;
- *address_of_string_pointer = first_digit + 3;
- return(0);
+ int return_value; /* 0 means OK. */
+ char *first_digit;
+ /* char *last_digit; JF unused */
+ int number_of_digits_before_decimal;
+ int number_of_digits_after_decimal;
+ long decimal_exponent;
+ int number_of_digits_available;
+ char digits_sign_char;
+
+ /*
+ * Scan the input string, abstracting (1)digits (2)decimal mark (3) exponent.
+ * It would be simpler to modify the string, but we don't; just to be nice
+ * to caller.
+ * We need to know how many digits we have, so we can allocate space for
+ * the digits' value.
+ */
+
+ char *p;
+ char c;
+ int seen_significant_digit;
+
+ first_digit = *address_of_string_pointer;
+ c = *first_digit;
+
+ if (c == '-' || c == '+')
+ {
+ digits_sign_char = c;
+ first_digit++;
+ }
+ else
+ digits_sign_char = '+';
+
+ if ((first_digit[0] == 'n' || first_digit[0] == 'N')
+ && (first_digit[1] == 'a' || first_digit[1] == 'A')
+ && (first_digit[2] == 'n' || first_digit[2] == 'N'))
+ {
+ address_of_generic_floating_point_number->sign = 0;
+ address_of_generic_floating_point_number->exponent = 0;
+ address_of_generic_floating_point_number->leader =
+ address_of_generic_floating_point_number->low;
+ *address_of_string_pointer = first_digit + 3;
+ return 0;
+ }
+
+ if ((first_digit[0] == 'i' || first_digit[0] == 'I')
+ && (first_digit[1] == 'n' || first_digit[1] == 'N')
+ && (first_digit[2] == 'f' || first_digit[2] == 'F'))
+ {
+ address_of_generic_floating_point_number->sign =
+ digits_sign_char == '+' ? 'P' : 'N';
+ address_of_generic_floating_point_number->exponent = 0;
+ address_of_generic_floating_point_number->leader =
+ address_of_generic_floating_point_number->low;
+
+ if ((first_digit[3] == 'i'
+ || first_digit[3] == 'I')
+ && (first_digit[4] == 'n'
+ || first_digit[4] == 'N')
+ && (first_digit[5] == 'i'
+ || first_digit[5] == 'I')
+ && (first_digit[6] == 't'
+ || first_digit[6] == 'T')
+ && (first_digit[7] == 'y'
+ || first_digit[7] == 'Y'))
+ {
+ *address_of_string_pointer = first_digit + 8;
}
-
- if ((first_digit[0] == 'i' || first_digit[0] == 'I')
- && (first_digit[1] == 'n' || first_digit[1] == 'N')
- && (first_digit[2] == 'f' || first_digit[2] == 'F')) {
- address_of_generic_floating_point_number->sign =
- digits_sign_char == '+' ? 'P' : 'N';
- address_of_generic_floating_point_number->exponent = 0;
- address_of_generic_floating_point_number->leader =
- address_of_generic_floating_point_number->low;
-
- if ((first_digit[3] == 'i'
- || first_digit[3] == 'I')
- && (first_digit[4] == 'n'
- || first_digit[4] == 'N')
- && (first_digit[5] == 'i'
- || first_digit[5] == 'I')
- && (first_digit[6] == 't'
- || first_digit[6] == 'T')
- && (first_digit[7] == 'y'
- || first_digit[7] == 'Y')) {
- *address_of_string_pointer = first_digit + 8;
- } else {
- *address_of_string_pointer = first_digit + 3;
- }
- return(0);
+ else
+ {
+ *address_of_string_pointer = first_digit + 3;
}
-
- number_of_digits_before_decimal = 0;
- number_of_digits_after_decimal = 0;
- decimal_exponent = 0;
- seen_significant_digit = 0;
- for (p = first_digit; (((c = * p) != '\0')
- && (!c || ! strchr(string_of_decimal_marks, c))
- && (!c || !strchr(string_of_decimal_exponent_marks, c)));
- p++) {
- if (isdigit(c)) {
- if (seen_significant_digit || c > '0') {
- ++number_of_digits_before_decimal;
- seen_significant_digit = 1;
- } else {
- first_digit++;
- }
- } else {
- break; /* p -> char after pre-decimal digits. */
- }
- } /* For each digit before decimal mark. */
-
+ return 0;
+ }
+
+ number_of_digits_before_decimal = 0;
+ number_of_digits_after_decimal = 0;
+ decimal_exponent = 0;
+ seen_significant_digit = 0;
+ for (p = first_digit;
+ (((c = *p) != '\0')
+ && (!c || !strchr (string_of_decimal_marks, c))
+ && (!c || !strchr (string_of_decimal_exponent_marks, c)));
+ p++)
+ {
+ if (isdigit (c))
+ {
+ if (seen_significant_digit || c > '0')
+ {
+ ++number_of_digits_before_decimal;
+ seen_significant_digit = 1;
+ }
+ else
+ {
+ first_digit++;
+ }
+ }
+ else
+ {
+ break; /* p -> char after pre-decimal digits. */
+ }
+ } /* For each digit before decimal mark. */
+
#ifndef OLD_FLOAT_READS
- /* Ignore trailing 0's after the decimal point. The original code here
- * (ifdef'd out) does not do this, and numbers like
- * 4.29496729600000000000e+09 (2**31)
- * come out inexact for some reason related to length of the digit
- * string.
- */
- if (c && strchr(string_of_decimal_marks, c)) {
- int zeros = 0; /* Length of current string of zeros */
-
- for (p++; (c = *p) && isdigit(c); p++) {
- if (c == '0') {
- zeros++;
- } else {
- number_of_digits_after_decimal += 1 + zeros;
- zeros = 0;
- }
- }
+ /* Ignore trailing 0's after the decimal point. The original code here
+ * (ifdef'd out) does not do this, and numbers like
+ * 4.29496729600000000000e+09 (2**31)
+ * come out inexact for some reason related to length of the digit
+ * string.
+ */
+ if (c && strchr (string_of_decimal_marks, c))
+ {
+ int zeros = 0; /* Length of current string of zeros */
+
+ for (p++; (c = *p) && isdigit (c); p++)
+ {
+ if (c == '0')
+ {
+ zeros++;
+ }
+ else
+ {
+ number_of_digits_after_decimal += 1 + zeros;
+ zeros = 0;
+ }
}
+ }
#else
- if (c && strchr(string_of_decimal_marks, c)) {
- for (p++; (((c = *p) != '\0')
- && (!c || !strchr(string_of_decimal_exponent_marks, c)));
- p++) {
- if (isdigit(c)) {
- number_of_digits_after_decimal++; /* This may be retracted below. */
- if (/* seen_significant_digit || */ c > '0') {
- seen_significant_digit = TRUE;
- }
- } else {
- if (!seen_significant_digit) {
- number_of_digits_after_decimal = 0;
- }
- break;
- }
- } /* For each digit after decimal mark. */
- }
-
- while (number_of_digits_after_decimal && first_digit[number_of_digits_before_decimal
- + number_of_digits_after_decimal] == '0')
- --number_of_digits_after_decimal;
- /* last_digit = p; JF unused */
-#endif
-
- if (c && strchr(string_of_decimal_exponent_marks, c) ) {
- char digits_exponent_sign_char;
-
- c = *++p;
- if (c && strchr ("+-",c)) {
- digits_exponent_sign_char = c;
- c = *++p;
- } else {
- digits_exponent_sign_char = '+';
- }
-
- for ( ; (c); c = *++p) {
- if (isdigit(c)) {
- decimal_exponent = decimal_exponent * 10 + c - '0';
- /*
- * BUG! If we overflow here, we lose!
- */
- } else {
- break;
- }
+ if (c && strchr (string_of_decimal_marks, c))
+ {
+ for (p++;
+ (((c = *p) != '\0')
+ && (!c || !strchr (string_of_decimal_exponent_marks, c)));
+ p++)
+ {
+ if (isdigit (c))
+ {
+ /* This may be retracted below. */
+ number_of_digits_after_decimal++;
+
+ if ( /* seen_significant_digit || */ c > '0')
+ {
+ seen_significant_digit = TRUE;
}
-
- if (digits_exponent_sign_char == '-') {
- decimal_exponent = -decimal_exponent;
+ }
+ else
+ {
+ if (!seen_significant_digit)
+ {
+ number_of_digits_after_decimal = 0;
}
+ break;
+ }
+ } /* For each digit after decimal mark. */
+ }
+
+ while (number_of_digits_after_decimal
+ && first_digit[number_of_digits_before_decimal
+ + number_of_digits_after_decimal] == '0')
+ --number_of_digits_after_decimal;
+#endif
+
+ if (c && strchr (string_of_decimal_exponent_marks, c))
+ {
+ char digits_exponent_sign_char;
+
+ c = *++p;
+ if (c && strchr ("+-", c))
+ {
+ digits_exponent_sign_char = c;
+ c = *++p;
+ }
+ else
+ {
+ digits_exponent_sign_char = '+';
}
-
- *address_of_string_pointer = p;
-
-
-
- number_of_digits_available =
- number_of_digits_before_decimal + number_of_digits_after_decimal;
- return_value = 0;
- if (number_of_digits_available == 0) {
- address_of_generic_floating_point_number->exponent = 0; /* Not strictly necessary */
- address_of_generic_floating_point_number->leader
- = -1 + address_of_generic_floating_point_number->low;
- address_of_generic_floating_point_number->sign = digits_sign_char;
- /* We have just concocted (+/-)0.0E0 */
-
- } else {
- int count; /* Number of useful digits left to scan. */
-
- LITTLENUM_TYPE *digits_binary_low;
- int precision;
- int maximum_useful_digits;
- int number_of_digits_to_use;
- int more_than_enough_bits_for_digits;
- int more_than_enough_littlenums_for_digits;
- int size_of_digits_in_littlenums;
- int size_of_digits_in_chars;
- FLONUM_TYPE power_of_10_flonum;
- FLONUM_TYPE digits_flonum;
-
- precision = (address_of_generic_floating_point_number->high
- - address_of_generic_floating_point_number->low
- + 1); /* Number of destination littlenums. */
-
- /* Includes guard bits (two littlenums worth) */
- maximum_useful_digits = (((double) (precision - 2))
- * ((double) (LITTLENUM_NUMBER_OF_BITS))
- / (LOG_TO_BASE_2_OF_10))
- + 2; /* 2 :: guard digits. */
-
- if (number_of_digits_available > maximum_useful_digits) {
- number_of_digits_to_use = maximum_useful_digits;
- } else {
- number_of_digits_to_use = number_of_digits_available;
+
+ for (; (c); c = *++p)
+ {
+ if (isdigit (c))
+ {
+ decimal_exponent = decimal_exponent * 10 + c - '0';
+ /*
+ * BUG! If we overflow here, we lose!
+ */
+ }
+ else
+ {
+ break;
+ }
+ }
+
+ if (digits_exponent_sign_char == '-')
+ {
+ decimal_exponent = -decimal_exponent;
+ }
+ }
+
+ *address_of_string_pointer = p;
+
+
+
+ number_of_digits_available =
+ number_of_digits_before_decimal + number_of_digits_after_decimal;
+ return_value = 0;
+ if (number_of_digits_available == 0)
+ {
+ address_of_generic_floating_point_number->exponent = 0; /* Not strictly necessary */
+ address_of_generic_floating_point_number->leader
+ = -1 + address_of_generic_floating_point_number->low;
+ address_of_generic_floating_point_number->sign = digits_sign_char;
+ /* We have just concocted (+/-)0.0E0 */
+
+ }
+ else
+ {
+ int count; /* Number of useful digits left to scan. */
+
+ LITTLENUM_TYPE *digits_binary_low;
+ unsigned int precision;
+ unsigned int maximum_useful_digits;
+ unsigned int number_of_digits_to_use;
+ unsigned int more_than_enough_bits_for_digits;
+ unsigned int more_than_enough_littlenums_for_digits;
+ unsigned int size_of_digits_in_littlenums;
+ unsigned int size_of_digits_in_chars;
+ FLONUM_TYPE power_of_10_flonum;
+ FLONUM_TYPE digits_flonum;
+
+ precision = (address_of_generic_floating_point_number->high
+ - address_of_generic_floating_point_number->low
+ + 1); /* Number of destination littlenums. */
+
+ /* Includes guard bits (two littlenums worth) */
+ maximum_useful_digits = (((double) (precision - 2))
+ * ((double) (LITTLENUM_NUMBER_OF_BITS))
+ / (LOG_TO_BASE_2_OF_10))
+ + 2; /* 2 :: guard digits. */
+
+ if (number_of_digits_available > maximum_useful_digits)
+ {
+ number_of_digits_to_use = maximum_useful_digits;
+ }
+ else
+ {
+ number_of_digits_to_use = number_of_digits_available;
+ }
+
+ /* Cast these to SIGNED LONG first, otherwise, on systems with
+ LONG wider than INT (such as Alpha OSF/1), unsignedness may
+ cause unexpected results. */
+ decimal_exponent += ((long) number_of_digits_before_decimal
+ - (long) number_of_digits_to_use);
+
+ more_than_enough_bits_for_digits
+ = ((((double) number_of_digits_to_use) * LOG_TO_BASE_2_OF_10) + 1);
+
+ more_than_enough_littlenums_for_digits
+ = (more_than_enough_bits_for_digits
+ / LITTLENUM_NUMBER_OF_BITS)
+ + 2;
+
+ /* Compute (digits) part. In "12.34E56" this is the "1234" part.
+ Arithmetic is exact here. If no digits are supplied then this
+ part is a 0 valued binary integer. Allocate room to build up
+ the binary number as littlenums. We want this memory to
+ disappear when we leave this function. Assume no alignment
+ problems => (room for n objects) == n * (room for 1
+ object). */
+
+ size_of_digits_in_littlenums = more_than_enough_littlenums_for_digits;
+ size_of_digits_in_chars = size_of_digits_in_littlenums
+ * sizeof (LITTLENUM_TYPE);
+
+ digits_binary_low = (LITTLENUM_TYPE *)
+ alloca (size_of_digits_in_chars);
+
+ memset ((char *) digits_binary_low, '\0', size_of_digits_in_chars);
+
+ /* Digits_binary_low[] is allocated and zeroed. */
+
+ /*
+ * Parse the decimal digits as if * digits_low was in the units position.
+ * Emit a binary number into digits_binary_low[].
+ *
+ * Use a large-precision version of:
+ * (((1st-digit) * 10 + 2nd-digit) * 10 + 3rd-digit ...) * 10 + last-digit
+ */
+
+ for (p = first_digit, count = number_of_digits_to_use; count; p++, --count)
+ {
+ c = *p;
+ if (isdigit (c))
+ {
+ /*
+ * Multiply by 10. Assume can never overflow.
+ * Add this digit to digits_binary_low[].
+ */
+
+ long carry;
+ LITTLENUM_TYPE *littlenum_pointer;
+ LITTLENUM_TYPE *littlenum_limit;
+
+ littlenum_limit = digits_binary_low
+ + more_than_enough_littlenums_for_digits
+ - 1;
+
+ carry = c - '0'; /* char -> binary */
+
+ for (littlenum_pointer = digits_binary_low;
+ littlenum_pointer <= littlenum_limit;
+ littlenum_pointer++)
+ {
+ long work;
+
+ work = carry + 10 * (long) (*littlenum_pointer);
+ *littlenum_pointer = work & LITTLENUM_MASK;
+ carry = work >> LITTLENUM_NUMBER_OF_BITS;
}
-
- decimal_exponent += number_of_digits_before_decimal - number_of_digits_to_use;
-
- more_than_enough_bits_for_digits
- = ((((double)number_of_digits_to_use) * LOG_TO_BASE_2_OF_10) + 1);
-
- more_than_enough_littlenums_for_digits
- = (more_than_enough_bits_for_digits
- / LITTLENUM_NUMBER_OF_BITS)
- + 2;
-
- /*
- * Compute (digits) part. In "12.34E56" this is the "1234" part.
- * Arithmetic is exact here. If no digits are supplied then
- * this part is a 0 valued binary integer.
- * Allocate room to build up the binary number as littlenums.
- * We want this memory to disappear when we leave this function.
- * Assume no alignment problems => (room for n objects) ==
- * n * (room for 1 object).
- */
-
- size_of_digits_in_littlenums = more_than_enough_littlenums_for_digits;
- size_of_digits_in_chars = size_of_digits_in_littlenums
- * sizeof(LITTLENUM_TYPE);
-
- digits_binary_low = (LITTLENUM_TYPE *)
- alloca(size_of_digits_in_chars);
-
- bzero((char *)digits_binary_low, size_of_digits_in_chars);
-
- /* Digits_binary_low[] is allocated and zeroed. */
-
- /*
- * Parse the decimal digits as if * digits_low was in the units position.
- * Emit a binary number into digits_binary_low[].
- *
- * Use a large-precision version of:
- * (((1st-digit) * 10 + 2nd-digit) * 10 + 3rd-digit ...) * 10 + last-digit
- */
-
- for (p = first_digit, count = number_of_digits_to_use; count; p++, --count) {
- c = *p;
- if (isdigit(c)) {
- /*
- * Multiply by 10. Assume can never overflow.
- * Add this digit to digits_binary_low[].
- */
-
- long carry;
- LITTLENUM_TYPE *littlenum_pointer;
- LITTLENUM_TYPE *littlenum_limit;
-
- littlenum_limit = digits_binary_low
- + more_than_enough_littlenums_for_digits
- - 1;
-
- carry = c - '0'; /* char -> binary */
-
- for (littlenum_pointer = digits_binary_low;
- littlenum_pointer <= littlenum_limit;
- littlenum_pointer++) {
- long work;
-
- work = carry + 10 * (long) (*littlenum_pointer);
- *littlenum_pointer = work & LITTLENUM_MASK;
- carry = work >> LITTLENUM_NUMBER_OF_BITS;
- }
-
- if (carry != 0) {
- /*
- * We have a GROSS internal error.
- * This should never happen.
- */
- as_fatal("failed sanity check."); /* RMS prefers abort() to any message. */
- }
- } else {
- ++ count; /* '.' doesn't alter digits used count. */
- } /* if valid digit */
- } /* for each digit */
-
-
- /*
- * Digits_binary_low[] properly encodes the value of the digits.
- * Forget about any high-order littlenums that are 0.
- */
- while (digits_binary_low[size_of_digits_in_littlenums - 1] == 0
- && size_of_digits_in_littlenums >= 2)
- size_of_digits_in_littlenums--;
-
- digits_flonum.low = digits_binary_low;
- digits_flonum.high = digits_binary_low + size_of_digits_in_littlenums - 1;
- digits_flonum.leader = digits_flonum.high;
- digits_flonum.exponent = 0;
- /*
- * The value of digits_flonum . sign should not be important.
- * We have already decided the output's sign.
- * We trust that the sign won't influence the other parts of the number!
- * So we give it a value for these reasons:
- * (1) courtesy to humans reading/debugging
- * these numbers so they don't get excited about strange values
- * (2) in future there may be more meaning attached to sign,
- * and what was
- * harmless noise may become disruptive, ill-conditioned (or worse)
- * input.
- */
- digits_flonum.sign = '+';
-
+
+ if (carry != 0)
{
- /*
- * Compute the mantssa (& exponent) of the power of 10.
- * If sucessful, then multiply the power of 10 by the digits
- * giving return_binary_mantissa and return_binary_exponent.
- */
-
- LITTLENUM_TYPE *power_binary_low;
- int decimal_exponent_is_negative;
- /* This refers to the "-56" in "12.34E-56". */
- /* FALSE: decimal_exponent is positive (or 0) */
- /* TRUE: decimal_exponent is negative */
- FLONUM_TYPE temporary_flonum;
- LITTLENUM_TYPE *temporary_binary_low;
- int size_of_power_in_littlenums;
- int size_of_power_in_chars;
-
- size_of_power_in_littlenums = precision;
- /* Precision has a built-in fudge factor so we get a few guard bits. */
-
- decimal_exponent_is_negative = decimal_exponent < 0;
- if (decimal_exponent_is_negative) {
- decimal_exponent = -decimal_exponent;
- }
-
- /* From now on: the decimal exponent is > 0. Its sign is seperate. */
-
- size_of_power_in_chars = size_of_power_in_littlenums
- * sizeof(LITTLENUM_TYPE) + 2;
-
- power_binary_low = (LITTLENUM_TYPE *) alloca(size_of_power_in_chars);
- temporary_binary_low = (LITTLENUM_TYPE *) alloca(size_of_power_in_chars);
- bzero((char *)power_binary_low, size_of_power_in_chars);
- * power_binary_low = 1;
- power_of_10_flonum.exponent = 0;
- power_of_10_flonum.low = power_binary_low;
- power_of_10_flonum.leader = power_binary_low;
- power_of_10_flonum.high = power_binary_low + size_of_power_in_littlenums - 1;
- power_of_10_flonum.sign = '+';
- temporary_flonum.low = temporary_binary_low;
- temporary_flonum.high = temporary_binary_low + size_of_power_in_littlenums - 1;
- /*
- * (power) == 1.
- * Space for temporary_flonum allocated.
- */
-
- /*
- * ...
- *
- * WHILE more bits
- * DO find next bit (with place value)
- * multiply into power mantissa
- * OD
- */
- {
- int place_number_limit;
- /* Any 10^(2^n) whose "n" exceeds this */
- /* value will fall off the end of */
- /* flonum_XXXX_powers_of_ten[]. */
- int place_number;
- const FLONUM_TYPE *multiplicand; /* -> 10^(2^n) */
-
- place_number_limit = table_size_of_flonum_powers_of_ten;
-
- multiplicand = (decimal_exponent_is_negative
- ? flonum_negative_powers_of_ten
- : flonum_positive_powers_of_ten);
-
- for (place_number = 1; /* Place value of this bit of exponent. */
- decimal_exponent; /* Quit when no more 1 bits in exponent. */
- decimal_exponent >>= 1, place_number++) {
- if (decimal_exponent & 1) {
- if (place_number > place_number_limit) {
- /*
- * The decimal exponent has a magnitude so great that
- * our tables can't help us fragment it. Although this
- * routine is in error because it can't imagine a
- * number that big, signal an error as if it is the
- * user's fault for presenting such a big number.
- */
- return_value = ERROR_EXPONENT_OVERFLOW;
- /*
- * quit out of loop gracefully
- */
- decimal_exponent = 0;
- } else {
+ /*
+ * We have a GROSS internal error.
+ * This should never happen.
+ */
+ as_fatal ("failed sanity check.");
+ }
+ }
+ else
+ {
+ ++count; /* '.' doesn't alter digits used count. */
+ }
+ }
+
+
+ /*
+ * Digits_binary_low[] properly encodes the value of the digits.
+ * Forget about any high-order littlenums that are 0.
+ */
+ while (digits_binary_low[size_of_digits_in_littlenums - 1] == 0
+ && size_of_digits_in_littlenums >= 2)
+ size_of_digits_in_littlenums--;
+
+ digits_flonum.low = digits_binary_low;
+ digits_flonum.high = digits_binary_low + size_of_digits_in_littlenums - 1;
+ digits_flonum.leader = digits_flonum.high;
+ digits_flonum.exponent = 0;
+ /*
+ * The value of digits_flonum . sign should not be important.
+ * We have already decided the output's sign.
+ * We trust that the sign won't influence the other parts of the number!
+ * So we give it a value for these reasons:
+ * (1) courtesy to humans reading/debugging
+ * these numbers so they don't get excited about strange values
+ * (2) in future there may be more meaning attached to sign,
+ * and what was
+ * harmless noise may become disruptive, ill-conditioned (or worse)
+ * input.
+ */
+ digits_flonum.sign = '+';
+
+ {
+ /*
+ * Compute the mantssa (& exponent) of the power of 10.
+ * If sucessful, then multiply the power of 10 by the digits
+ * giving return_binary_mantissa and return_binary_exponent.
+ */
+
+ LITTLENUM_TYPE *power_binary_low;
+ int decimal_exponent_is_negative;
+ /* This refers to the "-56" in "12.34E-56". */
+ /* FALSE: decimal_exponent is positive (or 0) */
+ /* TRUE: decimal_exponent is negative */
+ FLONUM_TYPE temporary_flonum;
+ LITTLENUM_TYPE *temporary_binary_low;
+ unsigned int size_of_power_in_littlenums;
+ unsigned int size_of_power_in_chars;
+
+ size_of_power_in_littlenums = precision;
+ /* Precision has a built-in fudge factor so we get a few guard bits. */
+
+ decimal_exponent_is_negative = decimal_exponent < 0;
+ if (decimal_exponent_is_negative)
+ {
+ decimal_exponent = -decimal_exponent;
+ }
+
+ /* From now on: the decimal exponent is > 0. Its sign is seperate. */
+
+ size_of_power_in_chars = size_of_power_in_littlenums
+ * sizeof (LITTLENUM_TYPE) + 2;
+
+ power_binary_low = (LITTLENUM_TYPE *) alloca (size_of_power_in_chars);
+ temporary_binary_low = (LITTLENUM_TYPE *) alloca (size_of_power_in_chars);
+ memset ((char *) power_binary_low, '\0', size_of_power_in_chars);
+ *power_binary_low = 1;
+ power_of_10_flonum.exponent = 0;
+ power_of_10_flonum.low = power_binary_low;
+ power_of_10_flonum.leader = power_binary_low;
+ power_of_10_flonum.high = power_binary_low + size_of_power_in_littlenums - 1;
+ power_of_10_flonum.sign = '+';
+ temporary_flonum.low = temporary_binary_low;
+ temporary_flonum.high = temporary_binary_low + size_of_power_in_littlenums - 1;
+ /*
+ * (power) == 1.
+ * Space for temporary_flonum allocated.
+ */
+
+ /*
+ * ...
+ *
+ * WHILE more bits
+ * DO find next bit (with place value)
+ * multiply into power mantissa
+ * OD
+ */
+ {
+ int place_number_limit;
+ /* Any 10^(2^n) whose "n" exceeds this */
+ /* value will fall off the end of */
+ /* flonum_XXXX_powers_of_ten[]. */
+ int place_number;
+ const FLONUM_TYPE *multiplicand; /* -> 10^(2^n) */
+
+ place_number_limit = table_size_of_flonum_powers_of_ten;
+
+ multiplicand = (decimal_exponent_is_negative
+ ? flonum_negative_powers_of_ten
+ : flonum_positive_powers_of_ten);
+
+ for (place_number = 1;/* Place value of this bit of exponent. */
+ decimal_exponent;/* Quit when no more 1 bits in exponent. */
+ decimal_exponent >>= 1, place_number++)
+ {
+ if (decimal_exponent & 1)
+ {
+ if (place_number > place_number_limit)
+ {
+ /* The decimal exponent has a magnitude so great
+ that our tables can't help us fragment it.
+ Although this routine is in error because it
+ can't imagine a number that big, signal an
+ error as if it is the user's fault for
+ presenting such a big number. */
+ return_value = ERROR_EXPONENT_OVERFLOW;
+ /* quit out of loop gracefully */
+ decimal_exponent = 0;
+ }
+ else
+ {
#ifdef TRACE
- printf("before multiply, place_number = %d., power_of_10_flonum:\n",
- place_number);
+ printf ("before multiply, place_number = %d., power_of_10_flonum:\n",
+ place_number);
- flonum_print(&power_of_10_flonum);
- (void)putchar('\n');
+ flonum_print (&power_of_10_flonum);
+ (void) putchar ('\n');
#endif
- flonum_multip(multiplicand + place_number,
- &power_of_10_flonum, &temporary_flonum);
- flonum_copy(&temporary_flonum, &power_of_10_flonum);
- } /* If this bit of decimal_exponent was computable.*/
- } /* If this bit of decimal_exponent was set. */
- } /* For each bit of binary representation of exponent */
+ flonum_multip (multiplicand + place_number,
+ &power_of_10_flonum, &temporary_flonum);
+ flonum_copy (&temporary_flonum, &power_of_10_flonum);
+ } /* If this bit of decimal_exponent was computable.*/
+ } /* If this bit of decimal_exponent was set. */
+ } /* For each bit of binary representation of exponent */
#ifdef TRACE
- printf(" after computing power_of_10_flonum: ");
- flonum_print(&power_of_10_flonum );
- (void) putchar('\n');
+ printf (" after computing power_of_10_flonum: ");
+ flonum_print (&power_of_10_flonum);
+ (void) putchar ('\n');
#endif
- }
-
- }
-
- /*
- * power_of_10_flonum is power of ten in binary (mantissa) , (exponent).
- * It may be the number 1, in which case we don't NEED to multiply.
- *
- * Multiply (decimal digits) by power_of_10_flonum.
- */
-
- flonum_multip(&power_of_10_flonum, &digits_flonum, address_of_generic_floating_point_number);
- /* Assert sign of the number we made is '+'. */
- address_of_generic_floating_point_number->sign = digits_sign_char;
-
- } /* If we had any significant digits. */
- return(return_value);
-} /* atof_generic () */
+ }
+
+ }
+
+ /*
+ * power_of_10_flonum is power of ten in binary (mantissa) , (exponent).
+ * It may be the number 1, in which case we don't NEED to multiply.
+ *
+ * Multiply (decimal digits) by power_of_10_flonum.
+ */
+
+ flonum_multip (&power_of_10_flonum, &digits_flonum, address_of_generic_floating_point_number);
+ /* Assert sign of the number we made is '+'. */
+ address_of_generic_floating_point_number->sign = digits_sign_char;
+
+ }
+ return return_value;
+}
/* end of atof_generic.c */
projects / binutils-gdb.git / commitdiff