Improving precision of ecma_number_to_string in case number can be represented as UInt32.

This commit is contained in:
Ruben Ayrapetyan
2014-09-03 15:05:58 +04:00
parent b275218e63
commit 76de0e9a06
2 changed files with 215 additions and 205 deletions
+212 -204
View File
@@ -444,7 +444,7 @@ ecma_number_to_int32 (ecma_number_t value) /**< unsigned 32-bit integer value */
* *
* Warning: * Warning:
* the conversion is not precise for all cases * the conversion is not precise for all cases
* For example, 12345.0f converts to "12344.99931". * For example, 12345.123f converts to "12345.12209".
* *
* @return length of zt-string * @return length of zt-string
*/ */
@@ -507,247 +507,255 @@ ecma_number_to_zt_string (ecma_number_t num, /**< ecma-number */
# error "!CONFIG_ECMA_NUMBER_FLOAT32 && !CONFIG_ECMA_NUMBER_FLOAT64" # error "!CONFIG_ECMA_NUMBER_FLOAT32 && !CONFIG_ECMA_NUMBER_FLOAT64"
#endif /* !CONFIG_ECMA_NUMBER_FLOAT32 && !CONFIG_ECMA_NUMBER_FLOAT64 */ #endif /* !CONFIG_ECMA_NUMBER_FLOAT32 && !CONFIG_ECMA_NUMBER_FLOAT64 */
uint64_t fraction_uint64; uint32_t num_uint32 = ecma_number_to_uint32 (num);
LL_T fraction; if (ecma_uint32_to_number (num_uint32) == num)
int32_t exponent;
int32_t dot_shift;
int32_t decimal_exp = 0;
dot_shift = ecma_number_get_fraction_and_exponent (num, &fraction_uint64, &exponent);
fraction = (LL_T) fraction_uint64;
JERRY_ASSERT (fraction == fraction_uint64);
if (exponent != 0)
{ {
ecma_number_t t = 1.0f; ecma_uint32_to_string (num_uint32, dst_p, buffer_size);
bool do_divide;
if (exponent < 0)
{
do_divide = true;
while (exponent <= 0)
{
t *= 2.0f;
exponent++;
if (t >= 10.0f)
{
t /= 10.0f;
decimal_exp--;
}
JERRY_ASSERT (t < 10.0f);
}
while (t > 1.0f)
{
exponent--;
t /= 2.0f;
}
}
else
{
do_divide = false;
while (exponent >= 0)
{
t *= 2.0f;
exponent--;
if (t >= 10.0f)
{
t /= 10.0f;
decimal_exp++;
}
JERRY_ASSERT (t < 10.0f);
}
while (t > 2.0f)
{
exponent++;
t /= 2.0f;
}
}
if (do_divide)
{
fraction = (LL_T) ((ecma_number_t) fraction / t);
}
else
{
fraction = (LL_T) ((ecma_number_t) fraction * t);
}
}
LL_T s;
int32_t n;
int32_t k;
if (exponent > 0)
{
fraction <<= exponent;
} }
else else
{ {
fraction >>= -exponent; uint64_t fraction_uint64;
} LL_T fraction;
int32_t exponent;
int32_t dot_shift;
int32_t decimal_exp = 0;
const int32_t int_part_shift = dot_shift; dot_shift = ecma_number_get_fraction_and_exponent (num, &fraction_uint64, &exponent);
const LL_T frac_part_mask = ((((LL_T)1) << int_part_shift) - 1);
LL_T int_part = fraction >> int_part_shift; fraction = (LL_T) fraction_uint64;
LL_T frac_part = fraction & frac_part_mask; JERRY_ASSERT (fraction == fraction_uint64);
s = int_part; if (exponent != 0)
k = 1;
n = decimal_exp + 1;
JERRY_ASSERT (int_part < 10);
while (k < LL_MAX_DIGITS
&& frac_part != 0)
{
frac_part *= 10;
LL_T new_frac_part = frac_part & frac_part_mask;
LL_T digit = (frac_part - new_frac_part) >> int_part_shift;
s = s * 10 + digit;
k++;
frac_part = new_frac_part;
}
// 6.
if (k <= n && n <= 21)
{
dst_p += n;
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * ((dst_p - buffer_p) + 1) <= buffer_size);
*dst_p = ECMA_CHAR_NULL;
for (int32_t i = 0; i < n - k; i++)
{ {
*--dst_p = digits [0]; ecma_number_t t = 1.0f;
bool do_divide;
if (exponent < 0)
{
do_divide = true;
while (exponent <= 0)
{
t *= 2.0f;
exponent++;
if (t >= 10.0f)
{
t /= 10.0f;
decimal_exp--;
}
JERRY_ASSERT (t < 10.0f);
}
while (t > 1.0f)
{
exponent--;
t /= 2.0f;
}
}
else
{
do_divide = false;
while (exponent >= 0)
{
t *= 2.0f;
exponent--;
if (t >= 10.0f)
{
t /= 10.0f;
decimal_exp++;
}
JERRY_ASSERT (t < 10.0f);
}
while (t > 2.0f)
{
exponent++;
t /= 2.0f;
}
}
if (do_divide)
{
fraction = (LL_T) ((ecma_number_t) fraction / t);
}
else
{
fraction = (LL_T) ((ecma_number_t) fraction * t);
}
} }
for (int32_t i = 0; i < k; i++) LL_T s;
int32_t n;
int32_t k;
if (exponent > 0)
{ {
*--dst_p = digits [s % 10]; fraction <<= exponent;
s /= 10;
}
}
else if (0 < n && n <= 21)
{
// 7.
dst_p += k + 1;
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * ((dst_p - buffer_p) + 1) <= buffer_size);
*dst_p = ECMA_CHAR_NULL;
for (int32_t i = 0; i < k - n; i++)
{
*--dst_p = digits [s % 10];
s /= 10;
}
*--dst_p = dot_char;
for (int32_t i = 0; i < n; i++)
{
*--dst_p = digits [s % 10];
s /= 10;
}
}
else if (-6 <= n && n <= 0)
{
// 8.
dst_p += k - n + 1 + 1;
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * ((dst_p - buffer_p) + 1) <= buffer_size);
*dst_p = ECMA_CHAR_NULL;
for (int32_t i = 0; i < k; i++)
{
*--dst_p = digits [s % 10];
s /= 10;
}
for (int32_t i = 0; i < -n; i++)
{
*--dst_p = digits [0];
}
*--dst_p = dot_char;
*--dst_p = digits[0];
}
else
{
if (k == 1)
{
// 9.
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) <= buffer_size);
*dst_p++ = digits [s % 10];
s /= 10;
} }
else else
{ {
// 10. fraction >>= -exponent;
}
const int32_t int_part_shift = dot_shift;
const LL_T frac_part_mask = ((((LL_T)1) << int_part_shift) - 1);
LL_T int_part = fraction >> int_part_shift;
LL_T frac_part = fraction & frac_part_mask;
s = int_part;
k = 1;
n = decimal_exp + 1;
JERRY_ASSERT (int_part < 10);
while (k < LL_MAX_DIGITS
&& frac_part != 0)
{
frac_part *= 10;
LL_T new_frac_part = frac_part & frac_part_mask;
LL_T digit = (frac_part - new_frac_part) >> int_part_shift;
s = s * 10 + digit;
k++;
frac_part = new_frac_part;
}
// 6.
if (k <= n && n <= 21)
{
dst_p += n;
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * ((dst_p - buffer_p) + 1) <= buffer_size);
*dst_p = ECMA_CHAR_NULL;
for (int32_t i = 0; i < n - k; i++)
{
*--dst_p = digits [0];
}
for (int32_t i = 0; i < k; i++)
{
*--dst_p = digits [s % 10];
s /= 10;
}
}
else if (0 < n && n <= 21)
{
// 7.
dst_p += k + 1; dst_p += k + 1;
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p) <= buffer_size); JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * ((dst_p - buffer_p) + 1) <= buffer_size);
for (int32_t i = 0; i < k - 1; i++) *dst_p = ECMA_CHAR_NULL;
for (int32_t i = 0; i < k - n; i++)
{ {
*--dst_p = digits [s % 10]; *--dst_p = digits [s % 10];
s /= 10; s /= 10;
} }
*--dst_p = dot_char; *--dst_p = dot_char;
*--dst_p = digits[s % 10];
s /= 10;
dst_p += k + 1; for (int32_t i = 0; i < n; i++)
{
*--dst_p = digits [s % 10];
s /= 10;
}
} }
else if (-6 <= n && n <= 0)
// 9., 10.
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p + 2) <= buffer_size);
*dst_p++ = e_chars[0];
*dst_p++ = (n >= 1) ? plus_char : minus_char;
int32_t t = (n >= 1) ? (n - 1) : -(n - 1);
if (t == 0)
{ {
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p + 1) <= buffer_size); // 8.
*dst_p++ = digits [0]; dst_p += k - n + 1 + 1;
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * ((dst_p - buffer_p) + 1) <= buffer_size);
*dst_p = ECMA_CHAR_NULL;
for (int32_t i = 0; i < k; i++)
{
*--dst_p = digits [s % 10];
s /= 10;
}
for (int32_t i = 0; i < -n; i++)
{
*--dst_p = digits [0];
}
*--dst_p = dot_char;
*--dst_p = digits[0];
} }
else else
{ {
int32_t t_mod = 1000000000u; if (k == 1)
while ((t / t_mod) == 0)
{ {
t_mod /= 10; // 9.
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) <= buffer_size);
JERRY_ASSERT (t_mod != 0); *dst_p++ = digits [s % 10];
s /= 10;
}
else
{
// 10.
dst_p += k + 1;
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p) <= buffer_size);
for (int32_t i = 0; i < k - 1; i++)
{
*--dst_p = digits [s % 10];
s /= 10;
}
*--dst_p = dot_char;
*--dst_p = digits[s % 10];
s /= 10;
dst_p += k + 1;
} }
while (t_mod != 0) // 9., 10.
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p + 2) <= buffer_size);
*dst_p++ = e_chars[0];
*dst_p++ = (n >= 1) ? plus_char : minus_char;
int32_t t = (n >= 1) ? (n - 1) : -(n - 1);
if (t == 0)
{ {
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p + 1) <= buffer_size); JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p + 1) <= buffer_size);
*dst_p++ = digits [t / t_mod]; *dst_p++ = digits [0];
t -= (t / t_mod) * t_mod;
t_mod /= 10;
} }
else
{
int32_t t_mod = 1000000000u;
while ((t / t_mod) == 0)
{
t_mod /= 10;
JERRY_ASSERT (t_mod != 0);
}
while (t_mod != 0)
{
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p + 1) <= buffer_size);
*dst_p++ = digits [t / t_mod];
t -= (t / t_mod) * t_mod;
t_mod /= 10;
}
}
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p + 1) <= buffer_size);
*dst_p++ = ECMA_CHAR_NULL;
} }
JERRY_ASSERT ((ssize_t) sizeof (ecma_char_t) * (dst_p - buffer_p + 1) <= buffer_size); JERRY_ASSERT (s == 0);
*dst_p++ = ECMA_CHAR_NULL;
} }
JERRY_ASSERT (s == 0);
} }
} }
+3 -1
View File
@@ -31,7 +31,8 @@ main( int __unused argc,
{ {
(const ecma_char_t*) "1", (const ecma_char_t*) "1",
(const ecma_char_t*) "0.5", (const ecma_char_t*) "0.5",
(const ecma_char_t*) "12344.99931", (const ecma_char_t*) "12345",
(const ecma_char_t*) "12345.12209",
(const ecma_char_t*) "1.401298403e-45", (const ecma_char_t*) "1.401298403e-45",
(const ecma_char_t*) "-2.5e+38", (const ecma_char_t*) "-2.5e+38",
(const ecma_char_t*) "NaN", (const ecma_char_t*) "NaN",
@@ -46,6 +47,7 @@ main( int __unused argc,
1.0f, 1.0f,
0.5f, 0.5f,
12345.0f, 12345.0f,
12345.123f,
1.0e-45f, 1.0e-45f,
-2.5e+38f, -2.5e+38f,
NAN, NAN,