diff options
Diffstat (limited to 'erts/emulator/sys/common')
| -rw-r--r-- | erts/emulator/sys/common/erl_sys_common_misc.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/erts/emulator/sys/common/erl_sys_common_misc.c b/erts/emulator/sys/common/erl_sys_common_misc.c index 79f87eb3a9..ddb414580a 100644 --- a/erts/emulator/sys/common/erl_sys_common_misc.c +++ b/erts/emulator/sys/common/erl_sys_common_misc.c @@ -160,7 +160,7 @@ sys_double_to_chars_fast(double f, char *buffer, int buffer_size, int decimals, { /* Note that some C compilers don't support "static const" propagation * so we use a defines */ - #define SYS_DOUBLE_RND_CONST 0.55555555555555555 + #define SYS_DOUBLE_RND_CONST 0.5 #define FRAC_SIZE 52 #define EXP_SIZE 11 #define EXP_MASK ((1ll << EXP_SIZE) - 1) @@ -256,11 +256,14 @@ sys_double_to_chars_fast(double f, char *buffer, int buffer_size, int decimals, return p - buffer; } else if (exp >= FRAC_SIZE) { int_part = mantissa << (exp - FRAC_SIZE); + exp = 0; } else if (exp >= 0) { int_part = mantissa >> (FRAC_SIZE - exp); frac_part = (mantissa << (exp + 1)) & FRAC_MASK2; + exp = 0; } else /* if (exp < 0) */ { - frac_part = (mantissa & FRAC_MASK2) >> -(exp + 1); + frac_part = mantissa; + exp = -(exp+1); } if (!int_part) { @@ -298,11 +301,22 @@ sys_double_to_chars_fast(double f, char *buffer, int buffer_size, int decimals, max = decimals; for (i = 0; i < max; i++) { - /* frac_part *= 10; */ - frac_part = (frac_part << 3) + (frac_part << 1); - - *p++ = (char)((frac_part >> (FRAC_SIZE + 1)) + '0'); - frac_part &= FRAC_MASK2; + if (frac_part > (ERTS_UINT64_MAX/16)) { + frac_part /= 16; + exp -= 4; + } + if (FRAC_SIZE + 1 + exp >= 64) { + *p++ = '0'; + frac_part *= 5; + exp--; + } + else + { + frac_part *= 10; + + *p++ = (char)((frac_part >> (FRAC_SIZE + 1 + exp)) + '0'); + frac_part &= (1ll << (FRAC_SIZE + 1 + exp)) - 1; + } } /* Delete trailing zeroes */ |