diff options
Diffstat (limited to 'stdlib/strtod.c')
| -rw-r--r-- | stdlib/strtod.c | 46 |
1 files changed, 32 insertions, 14 deletions
diff --git a/stdlib/strtod.c b/stdlib/strtod.c index 8f71d136de..dcec00c5d7 100644 --- a/stdlib/strtod.c +++ b/stdlib/strtod.c @@ -27,7 +27,6 @@ Cambridge, MA 02139, USA. */ #define STRTOF strtod #define MPN2FLOAT __mpn_construct_double #define FLOAT_HUGE_VAL HUGE_VAL -#define IMPLICIT_ONE 1 #endif /* End of configuration part. */ @@ -54,7 +53,6 @@ Cambridge, MA 02139, USA. */ #define MIN_EXP PASTE(FLT,_MIN_EXP) #define MAX_10_EXP PASTE(FLT,_MAX_10_EXP) #define MIN_10_EXP PASTE(FLT,_MIN_10_EXP) -#define MAX_10_EXP_LOG PASTE(FLT,_MAX_10_EXP_LOG) /* Extra macros required to get FLT expanded before the pasting. */ #define PASTE(a,b) PASTE1(a,b) @@ -102,7 +100,7 @@ static const mp_limb _tens_in_limb[MAX_DIG_PER_LIMB + 1] = #define RETURN_LIMB_SIZE howmany (MANT_DIG, BITS_PER_MP_LIMB) #define RETURN(val,end) \ - do { if (endptr != 0) *endptr = (char *) (end); return (val); } while (0) + do { if (endptr != 0) *endptr = (char *) (end); return val; } while (0) /* Maximum size necessary for mpn integers to hold floating point numbers. */ #define MPNSIZE (howmany (MAX_EXP + 2 * MANT_DIG, BITS_PER_MP_LIMB) \ @@ -120,21 +118,38 @@ static inline FLOAT round_and_return (mp_limb *retval, int exponent, int negative, mp_limb round_limb, mp_size_t round_bit, int more_bits) { - if (exponent < MIN_EXP - 2 + IMPLICIT_ONE) + if (exponent < MIN_EXP - 1) { - mp_size_t shift = MIN_EXP - 2 + IMPLICIT_ONE - exponent; + mp_size_t shift = MIN_EXP - 1 - exponent; - if (shift >= MANT_DIG) + if (shift > MANT_DIG) { errno = EDOM; return 0.0; } more_bits |= (round_limb & ((1 << round_bit) - 1)) != 0; - if (shift >= BITS_PER_MP_LIMB) + if (shift == MANT_DIG) + /* This is a special case to handle the very seldom case where + the mantissa will be empty after the shift. */ { + int i; + + round_limb = retval[RETURN_LIMB_SIZE - 1]; + round_bit = BITS_PER_MP_LIMB - 1; + for (i = 0; i < RETURN_LIMB_SIZE; ++i) + more_bits |= retval[i] != 0; + MPN_ZERO (retval, RETURN_LIMB_SIZE); + } + else if (shift >= BITS_PER_MP_LIMB) + { + int i; + round_limb = retval[(shift - 1) / BITS_PER_MP_LIMB]; round_bit = (shift - 1) % BITS_PER_MP_LIMB; + for (i = 0; i < (shift - 1) / BITS_PER_MP_LIMB; ++i) + more_bits |= retval[i] != 0; + more_bits |= (round_limb & ((1 << round_bit) - 1)) != 0; (void) __mpn_rshift (retval, &retval[shift / BITS_PER_MP_LIMB], RETURN_LIMB_SIZE - (shift / BITS_PER_MP_LIMB), @@ -167,7 +182,7 @@ round_and_return (mp_limb *retval, int exponent, int negative, retval[RETURN_LIMB_SIZE - 1] |= 1 << ((MANT_DIG - 1) % BITS_PER_MP_LIMB); } - else if (IMPLICIT_ONE && exponent == MIN_EXP - 2 + else if (exponent == MIN_EXP - 2 && (retval[RETURN_LIMB_SIZE - 1] & (1 << ((MANT_DIG - 1) % BITS_PER_MP_LIMB))) != 0) /* The number was denormalized but now normalized. */ @@ -390,9 +405,13 @@ INTERNAL (STRTOF) (nptr, endptr, group) Return current read pointer. */ if (!isdigit (c) && c != decimal) { - tp = correctly_grouped_prefix (start_of_digits, cp, thousands, grouping); - /* If TP is at the start of the digits, there was no correctly - grouped prefix of the string; so no number found. */ + if (grouping) + /* Check the grouping of the digits. */ + tp = correctly_grouped_prefix (start_of_digits, cp, thousands, + grouping); + else + tp = cp; + RETURN (0.0, tp == start_of_digits ? nptr : tp); } @@ -418,7 +437,7 @@ INTERNAL (STRTOF) (nptr, endptr, group) /* Check the grouping of the digits. */ tp = correctly_grouped_prefix (start_of_digits, cp, thousands, grouping); if (cp != tp) - { + { /* Less than the entire string was correctly grouped. */ if (tp == start_of_digits) @@ -539,7 +558,7 @@ INTERNAL (STRTOF) (nptr, endptr, group) assert (dig_no >= int_no); } - number_parsed: + number_parsed: /* The whole string is parsed. Store the address of the next character. */ if (endptr) @@ -584,7 +603,6 @@ INTERNAL (STRTOF) (nptr, endptr, group) int expbit = 1; const struct mp_power *ttab = &_fpioconst_pow10[0]; - assert (exponent < (1 << (MAX_10_EXP_LOG + 1))); do { if ((exponent & expbit) != 0) |