diff options
Diffstat (limited to 'contrib/binutils/gas/config/atof-ieee.c')
| -rw-r--r-- | contrib/binutils/gas/config/atof-ieee.c | 205 |
1 files changed, 104 insertions, 101 deletions
diff --git a/contrib/binutils/gas/config/atof-ieee.c b/contrib/binutils/gas/config/atof-ieee.c index 2e3c0dc..2a916cd 100644 --- a/contrib/binutils/gas/config/atof-ieee.c +++ b/contrib/binutils/gas/config/atof-ieee.c @@ -29,7 +29,7 @@ static void unget_bits PARAMS ((int)); static void make_invalid_floating_point_number PARAMS ((LITTLENUM_TYPE *)); extern const char EXP_CHARS[]; -/* Precision in LittleNums. */ +/* Precision in LittleNums. */ /* Don't count the gap in the m68k extended precision format. */ #define MAX_PRECISION (5) #define F_PRECISION (2) @@ -37,7 +37,7 @@ extern const char EXP_CHARS[]; #define X_PRECISION (5) #define P_PRECISION (5) -/* Length in LittleNums of guard bits. */ +/* Length in LittleNums of guard bits. */ #define GUARD (2) static const unsigned long mask[] = @@ -77,7 +77,6 @@ static const unsigned long mask[] = 0xffffffff, }; - static int bits_left_in_littlenum; static int littlenums_left; static LITTLENUM_TYPE *littlenum_pointer; @@ -100,18 +99,22 @@ next_bits (number_of_bits) { bits_left_in_littlenum = LITTLENUM_NUMBER_OF_BITS - number_of_bits; --littlenum_pointer; - return_value |= (*littlenum_pointer >> bits_left_in_littlenum) & mask[number_of_bits]; + return_value |= + (*littlenum_pointer >> bits_left_in_littlenum) + & mask[number_of_bits]; } } else { bits_left_in_littlenum -= number_of_bits; - return_value = mask[number_of_bits] & (*littlenum_pointer >> bits_left_in_littlenum); + return_value = + mask[number_of_bits] & (*littlenum_pointer >> bits_left_in_littlenum); } - return (return_value); + return return_value; } -/* Num had better be less than LITTLENUM_NUMBER_OF_BITS */ +/* Num had better be less than LITTLENUM_NUMBER_OF_BITS. */ + static void unget_bits (num) int num; @@ -124,7 +127,8 @@ unget_bits (num) } else if (bits_left_in_littlenum + num > LITTLENUM_NUMBER_OF_BITS) { - bits_left_in_littlenum = num - (LITTLENUM_NUMBER_OF_BITS - bits_left_in_littlenum); + bits_left_in_littlenum = + num - (LITTLENUM_NUMBER_OF_BITS - bits_left_in_littlenum); ++littlenum_pointer; ++littlenums_left; } @@ -137,7 +141,8 @@ make_invalid_floating_point_number (words) LITTLENUM_TYPE *words; { as_bad (_("cannot create floating-point number")); - words[0] = (LITTLENUM_TYPE) ((unsigned) -1) >> 1; /* Zero the leftmost bit */ + /* Zero the leftmost bit. */ + words[0] = (LITTLENUM_TYPE) ((unsigned) -1) >> 1; words[1] = (LITTLENUM_TYPE) -1; words[2] = (LITTLENUM_TYPE) -1; words[3] = (LITTLENUM_TYPE) -1; @@ -145,29 +150,27 @@ make_invalid_floating_point_number (words) words[5] = (LITTLENUM_TYPE) -1; } -/************************************************************************\ - * Warning: this returns 16-bit LITTLENUMs. It is up to the caller * - * to figure out any alignment problems and to conspire for the * - * bytes/word to be emitted in the right order. Bigendians beware! * - * * -\************************************************************************/ +/* Warning: This returns 16-bit LITTLENUMs. It is up to the caller to + figure out any alignment problems and to conspire for the + bytes/word to be emitted in the right order. Bigendians beware! */ /* Note that atof-ieee always has X and P precisions enabled. it is up to md_atof to filter them out if the target machine does not support them. */ -/* Returns pointer past text consumed. */ +/* Returns pointer past text consumed. */ + char * atof_ieee (str, what_kind, words) - char *str; /* Text to convert to binary. */ - int what_kind; /* 'd', 'f', 'g', 'h' */ - LITTLENUM_TYPE *words; /* Build the binary here. */ + char *str; /* Text to convert to binary. */ + int what_kind; /* 'd', 'f', 'g', 'h'. */ + LITTLENUM_TYPE *words; /* Build the binary here. */ { - /* Extra bits for zeroed low-order bits. The 1st MAX_PRECISION are - zeroed, the last contain flonum bits. */ + /* Extra bits for zeroed low-order bits. + The 1st MAX_PRECISION are zeroed, the last contain flonum bits. */ static LITTLENUM_TYPE bits[MAX_PRECISION + MAX_PRECISION + GUARD]; char *return_value; - /* Number of 16-bit words in the format. */ + /* Number of 16-bit words in the format. */ int precision; long exponent_bits; FLONUM_TYPE save_gen_flonum; @@ -186,7 +189,7 @@ atof_ieee (str, what_kind, words) generic_floating_point_number.sign = '\0'; /* Use more LittleNums than seems necessary: the highest flonum may - have 15 leading 0 bits, so could be useless. */ + have 15 leading 0 bits, so could be useless. */ memset (bits, '\0', sizeof (LITTLENUM_TYPE) * MAX_PRECISION); @@ -247,6 +250,7 @@ atof_ieee (str, what_kind, words) } /* Turn generic_floating_point_number into a real float/double/extended. */ + int gen_to_words (words, precision, exponent_bits) LITTLENUM_TYPE *words; @@ -274,17 +278,17 @@ gen_to_words (words, precision, exponent_bits) if (generic_floating_point_number.low > generic_floating_point_number.leader) { - /* 0.0e0 seen. */ + /* 0.0e0 seen. */ if (generic_floating_point_number.sign == '+') words[0] = 0x0000; else words[0] = 0x8000; memset (&words[1], '\0', (words_end - words - 1) * sizeof (LITTLENUM_TYPE)); - return (return_value); + return return_value; } - /* NaN: Do the right thing */ + /* NaN: Do the right thing. */ if (generic_floating_point_number.sign == 0) { if (precision == F_PRECISION) @@ -301,17 +305,17 @@ gen_to_words (words, precision, exponent_bits) words[3] = 0xffff; words[4] = 0xffff; words[5] = 0xffff; -#else /* ! TC_M68K */ +#else /* ! TC_M68K */ #ifdef TC_I386 words[0] = 0xffff; words[1] = 0xc000; words[2] = 0; words[3] = 0; words[4] = 0; -#else /* ! TC_I386 */ +#else /* ! TC_I386 */ abort (); -#endif /* ! TC_I386 */ -#endif /* ! TC_M68K */ +#endif /* ! TC_I386 */ +#endif /* ! TC_M68K */ } else { @@ -324,7 +328,7 @@ gen_to_words (words, precision, exponent_bits) } else if (generic_floating_point_number.sign == 'P') { - /* +INF: Do the right thing */ + /* +INF: Do the right thing. */ if (precision == F_PRECISION) { words[0] = 0x7f80; @@ -339,17 +343,17 @@ gen_to_words (words, precision, exponent_bits) words[3] = 0; words[4] = 0; words[5] = 0; -#else /* ! TC_M68K */ +#else /* ! TC_M68K */ #ifdef TC_I386 words[0] = 0x7fff; words[1] = 0x8000; words[2] = 0; words[3] = 0; words[4] = 0; -#else /* ! TC_I386 */ +#else /* ! TC_I386 */ abort (); -#endif /* ! TC_I386 */ -#endif /* ! TC_M68K */ +#endif /* ! TC_I386 */ +#endif /* ! TC_M68K */ } else { @@ -358,11 +362,11 @@ gen_to_words (words, precision, exponent_bits) words[2] = 0; words[3] = 0; } - return (return_value); + return return_value; } else if (generic_floating_point_number.sign == 'N') { - /* Negative INF */ + /* Negative INF. */ if (precision == F_PRECISION) { words[0] = 0xff80; @@ -377,17 +381,17 @@ gen_to_words (words, precision, exponent_bits) words[3] = 0; words[4] = 0; words[5] = 0; -#else /* ! TC_M68K */ +#else /* ! TC_M68K */ #ifdef TC_I386 words[0] = 0xffff; words[1] = 0x8000; words[2] = 0; words[3] = 0; words[4] = 0; -#else /* ! TC_I386 */ +#else /* ! TC_I386 */ abort (); -#endif /* ! TC_I386 */ -#endif /* ! TC_M68K */ +#endif /* ! TC_I386 */ +#endif /* ! TC_M68K */ } else { @@ -396,46 +400,49 @@ gen_to_words (words, precision, exponent_bits) words[2] = 0x0; words[3] = 0x0; } - return (return_value); + return return_value; } - /* - * The floating point formats we support have: - * Bit 15 is sign bit. - * Bits 14:n are excess-whatever exponent. - * Bits n-1:0 (if any) are most significant bits of fraction. - * Bits 15:0 of the next word(s) are the next most significant bits. - * - * So we need: number of bits of exponent, number of bits of - * mantissa. - */ + + /* The floating point formats we support have: + Bit 15 is sign bit. + Bits 14:n are excess-whatever exponent. + Bits n-1:0 (if any) are most significant bits of fraction. + Bits 15:0 of the next word(s) are the next most significant bits. + + So we need: number of bits of exponent, number of bits of + mantissa. */ bits_left_in_littlenum = LITTLENUM_NUMBER_OF_BITS; littlenum_pointer = generic_floating_point_number.leader; littlenums_left = (1 + generic_floating_point_number.leader - generic_floating_point_number.low); - /* Seek (and forget) 1st significant bit */ + + /* Seek (and forget) 1st significant bit. */ for (exponent_skippage = 0; !next_bits (1); ++exponent_skippage);; exponent_1 = (generic_floating_point_number.exponent + generic_floating_point_number.leader + 1 - generic_floating_point_number.low); + /* Radix LITTLENUM_RADIX, point just higher than - generic_floating_point_number.leader. */ + generic_floating_point_number.leader. */ exponent_2 = exponent_1 * LITTLENUM_NUMBER_OF_BITS; - /* Radix 2. */ + + /* Radix 2. */ exponent_3 = exponent_2 - exponent_skippage; - /* Forget leading zeros, forget 1st bit. */ + + /* Forget leading zeros, forget 1st bit. */ exponent_4 = exponent_3 + ((1 << (exponent_bits - 1)) - 2); - /* Offset exponent. */ + /* Offset exponent. */ lp = words; - /* Word 1. Sign, exponent and perhaps high bits. */ + /* Word 1. Sign, exponent and perhaps high bits. */ word1 = ((generic_floating_point_number.sign == '+') ? 0 : (1 << (LITTLENUM_NUMBER_OF_BITS - 1))); - /* Assume 2's complement integers. */ + /* Assume 2's complement integers. */ if (exponent_4 <= 0) { int prec_bits; @@ -443,7 +450,8 @@ gen_to_words (words, precision, exponent_bits) unget_bits (1); num_bits = -exponent_4; - prec_bits = LITTLENUM_NUMBER_OF_BITS * precision - (exponent_bits + 1 + num_bits); + prec_bits = + LITTLENUM_NUMBER_OF_BITS * precision - (exponent_bits + 1 + num_bits); #ifdef TC_I386 if (precision == X_PRECISION && exponent_bits == 15) { @@ -457,14 +465,15 @@ gen_to_words (words, precision, exponent_bits) if (num_bits >= LITTLENUM_NUMBER_OF_BITS - exponent_bits) { - /* Bigger than one littlenum */ + /* Bigger than one littlenum. */ num_bits -= (LITTLENUM_NUMBER_OF_BITS - 1) - exponent_bits; *lp++ = word1; - if (num_bits + exponent_bits + 1 > precision * LITTLENUM_NUMBER_OF_BITS) + if (num_bits + exponent_bits + 1 + > precision * LITTLENUM_NUMBER_OF_BITS) { - /* Exponent overflow */ + /* Exponent overflow. */ make_invalid_floating_point_number (words); - return (return_value); + return return_value; } #ifdef TC_M68K if (precision == X_PRECISION && exponent_bits == 15) @@ -490,14 +499,15 @@ gen_to_words (words, precision, exponent_bits) } else { - word1 |= next_bits ((LITTLENUM_NUMBER_OF_BITS - 1) - (exponent_bits + num_bits)); + word1 |= next_bits ((LITTLENUM_NUMBER_OF_BITS - 1) + - (exponent_bits + num_bits)); *lp++ = word1; } } while (lp < words_end) *lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS); - /* Round the mantissa up, but don't change the number */ + /* Round the mantissa up, but don't change the number. */ if (next_bits (1)) { --lp; @@ -570,15 +580,11 @@ gen_to_words (words, precision, exponent_bits) } else if ((unsigned long) exponent_4 >= mask[exponent_bits]) { - /* - * Exponent overflow. Lose immediately. - */ - - /* - * We leave return_value alone: admit we read the - * number, but return a floating exception - * because we can't encode the number. - */ + /* Exponent overflow. Lose immediately. */ + + /* We leave return_value alone: admit we read the + number, but return a floating exception + because we can't encode the number. */ make_invalid_floating_point_number (words); return return_value; } @@ -591,7 +597,7 @@ gen_to_words (words, precision, exponent_bits) *lp++ = word1; /* X_PRECISION is special: on the 68k, it has 16 bits of zero in the - middle. Either way, it is then followed by a 1 bit. */ + middle. Either way, it is then followed by a 1 bit. */ if (exponent_bits == 15 && precision == X_PRECISION) { #ifdef TC_M68K @@ -601,21 +607,19 @@ gen_to_words (words, precision, exponent_bits) | next_bits (LITTLENUM_NUMBER_OF_BITS - 1)); } - /* The rest of the words are just mantissa bits. */ + /* The rest of the words are just mantissa bits. */ while (lp < words_end) *lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS); if (next_bits (1)) { unsigned long carry; - /* - * Since the NEXT bit is a 1, round UP the mantissa. - * The cunning design of these hidden-1 floats permits - * us to let the mantissa overflow into the exponent, and - * it 'does the right thing'. However, we lose if the - * highest-order bit of the lowest-order word flips. - * Is that clear? - */ + /* Since the NEXT bit is a 1, round UP the mantissa. + The cunning design of these hidden-1 floats permits + us to let the mantissa overflow into the exponent, and + it 'does the right thing'. However, we lose if the + highest-order bit of the lowest-order word flips. + Is that clear? */ /* #if (sizeof(carry)) < ((sizeof(bits[0]) * BITS_PER_CHAR) + 2) Please allow at least 1 more bit in carry than is in a LITTLENUM. @@ -640,33 +644,36 @@ gen_to_words (words, precision, exponent_bits) { #ifdef TC_M68K /* On the m68k there is a gap of 16 bits. We must - explicitly propagate the carry into the exponent. */ + explicitly propagate the carry into the exponent. */ words[0] += words[1]; words[1] = 0; lp++; #endif - /* Put back the integer bit. */ + /* Put back the integer bit. */ lp[1] |= 1 << (LITTLENUM_NUMBER_OF_BITS - 1); } - } + } if ((word1 ^ *words) & (1 << (LITTLENUM_NUMBER_OF_BITS - 1))) { - /* We leave return_value alone: admit we read the - * number, but return a floating exception - * because we can't encode the number. - */ + /* We leave return_value alone: admit we read the number, + but return a floating exception because we can't encode + the number. */ *words &= ~(1 << (LITTLENUM_NUMBER_OF_BITS - 1)); - /* make_invalid_floating_point_number (words); */ - /* return return_value; */ +#if 0 + make_invalid_floating_point_number (words); + return return_value; +#endif } } - return (return_value); + return return_value; } -#if 0 /* unused */ +#if 0 +/* Unused. */ /* This routine is a real kludge. Someone really should do it better, but I'm too lazy, and I don't understand this stuff all too well anyway. (JF) */ + static void int_to_gen (x) long x; @@ -705,13 +712,9 @@ print_gen (gen) sprintf (sbuf + strlen (sbuf), "%x %x %.12g\n", arr[0], arr[1], fv); if (gen) - { - generic_floating_point_number = f; - } + generic_floating_point_number = f; return (sbuf); } #endif - -/* end of atof-ieee.c */ |
