Reformat and add a comment

This commit is contained in:
Victor Zverovich 2018-08-15 06:54:43 -07:00
parent 8bbb0b48b4
commit 9de312112a
3 changed files with 32 additions and 25 deletions

View File

@ -281,28 +281,35 @@ const uint64_t basic_data<T>::POWERS_OF_10_64[] = {
// These are generated by support/compute-powers.py.
template <typename T>
const uint64_t basic_data<T>::POW10_SIGNIFICANDS[] = {
0xfa8fd5a0081c0288, 0xbaaee17fa23ebf76, 0x8b16fb203055ac76, 0xcf42894a5dce35ea,
0x9a6bb0aa55653b2d, 0xe61acf033d1a45df, 0xab70fe17c79ac6ca, 0xff77b1fcbebcdc4f,
0xbe5691ef416bd60c, 0x8dd01fad907ffc3c, 0xd3515c2831559a83, 0x9d71ac8fada6c9b5,
0xea9c227723ee8bcb, 0xaecc49914078536d, 0x823c12795db6ce57, 0xc21094364dfb5637,
0x9096ea6f3848984f, 0xd77485cb25823ac7, 0xa086cfcd97bf97f4, 0xef340a98172aace5,
0xb23867fb2a35b28e, 0x84c8d4dfd2c63f3b, 0xc5dd44271ad3cdba, 0x936b9fcebb25c996,
0xdbac6c247d62a584, 0xa3ab66580d5fdaf6, 0xf3e2f893dec3f126, 0xb5b5ada8aaff80b8,
0x87625f056c7c4a8b, 0xc9bcff6034c13053, 0x964e858c91ba2655, 0xdff9772470297ebd,
0xa6dfbd9fb8e5b88f, 0xf8a95fcf88747d94, 0xb94470938fa89bcf, 0x8a08f0f8bf0f156b,
0xcdb02555653131b6, 0x993fe2c6d07b7fac, 0xe45c10c42a2b3b06, 0xaa242499697392d3,
0xfd87b5f28300ca0e, 0xbce5086492111aeb, 0x8cbccc096f5088cc, 0xd1b71758e219652c,
0x9c40000000000000, 0xe8d4a51000000000, 0xad78ebc5ac620000, 0x813f3978f8940984,
0xc097ce7bc90715b3, 0x8f7e32ce7bea5c70, 0xd5d238a4abe98068, 0x9f4f2726179a2245,
0xed63a231d4c4fb27, 0xb0de65388cc8ada8, 0x83c7088e1aab65db, 0xc45d1df942711d9a,
0x924d692ca61be758, 0xda01ee641a708dea, 0xa26da3999aef774a, 0xf209787bb47d6b85,
0xb454e4a179dd1877, 0x865b86925b9bc5c2, 0xc83553c5c8965d3d, 0x952ab45cfa97a0b3,
0xde469fbd99a05fe3, 0xa59bc234db398c25, 0xf6c69a72a3989f5c, 0xb7dcbf5354e9bece,
0x88fcf317f22241e2, 0xcc20ce9bd35c78a5, 0x98165af37b2153df, 0xe2a0b5dc971f303a,
0xa8d9d1535ce3b396, 0xfb9b7cd9a4a7443c, 0xbb764c4ca7a44410, 0x8bab8eefb6409c1a,
0xd01fef10a657842c, 0x9b10a4e5e9913129, 0xe7109bfba19c0c9d, 0xac2820d9623bf429,
0x80444b5e7aa7cf85, 0xbf21e44003acdd2d, 0x8e679c2f5e44ff8f, 0xd433179d9c8cb841,
0x9e19db92b4e31ba9, 0xeb96bf6ebadf77d9, 0xaf87023b9bf0ee6b
0xfa8fd5a0081c0288, 0xbaaee17fa23ebf76, 0x8b16fb203055ac76,
0xcf42894a5dce35ea, 0x9a6bb0aa55653b2d, 0xe61acf033d1a45df,
0xab70fe17c79ac6ca, 0xff77b1fcbebcdc4f, 0xbe5691ef416bd60c,
0x8dd01fad907ffc3c, 0xd3515c2831559a83, 0x9d71ac8fada6c9b5,
0xea9c227723ee8bcb, 0xaecc49914078536d, 0x823c12795db6ce57,
0xc21094364dfb5637, 0x9096ea6f3848984f, 0xd77485cb25823ac7,
0xa086cfcd97bf97f4, 0xef340a98172aace5, 0xb23867fb2a35b28e,
0x84c8d4dfd2c63f3b, 0xc5dd44271ad3cdba, 0x936b9fcebb25c996,
0xdbac6c247d62a584, 0xa3ab66580d5fdaf6, 0xf3e2f893dec3f126,
0xb5b5ada8aaff80b8, 0x87625f056c7c4a8b, 0xc9bcff6034c13053,
0x964e858c91ba2655, 0xdff9772470297ebd, 0xa6dfbd9fb8e5b88f,
0xf8a95fcf88747d94, 0xb94470938fa89bcf, 0x8a08f0f8bf0f156b,
0xcdb02555653131b6, 0x993fe2c6d07b7fac, 0xe45c10c42a2b3b06,
0xaa242499697392d3, 0xfd87b5f28300ca0e, 0xbce5086492111aeb,
0x8cbccc096f5088cc, 0xd1b71758e219652c, 0x9c40000000000000,
0xe8d4a51000000000, 0xad78ebc5ac620000, 0x813f3978f8940984,
0xc097ce7bc90715b3, 0x8f7e32ce7bea5c70, 0xd5d238a4abe98068,
0x9f4f2726179a2245, 0xed63a231d4c4fb27, 0xb0de65388cc8ada8,
0x83c7088e1aab65db, 0xc45d1df942711d9a, 0x924d692ca61be758,
0xda01ee641a708dea, 0xa26da3999aef774a, 0xf209787bb47d6b85,
0xb454e4a179dd1877, 0x865b86925b9bc5c2, 0xc83553c5c8965d3d,
0x952ab45cfa97a0b3, 0xde469fbd99a05fe3, 0xa59bc234db398c25,
0xf6c69a72a3989f5c, 0xb7dcbf5354e9bece, 0x88fcf317f22241e2,
0xcc20ce9bd35c78a5, 0x98165af37b2153df, 0xe2a0b5dc971f303a,
0xa8d9d1535ce3b396, 0xfb9b7cd9a4a7443c, 0xbb764c4ca7a44410,
0x8bab8eefb6409c1a, 0xd01fef10a657842c, 0x9b10a4e5e9913129,
0xe7109bfba19c0c9d, 0xac2820d9623bf429, 0x80444b5e7aa7cf85,
0xbf21e44003acdd2d, 0x8e679c2f5e44ff8f, 0xd433179d9c8cb841,
0x9e19db92b4e31ba9, 0xeb96bf6ebadf77d9, 0xaf87023b9bf0ee6b,
};
// Binary exponents of pow(10, k), for k = -348, -340, ..., 340, corresponding
@ -339,7 +346,7 @@ FMT_FUNC fp get_cached_power(int min_exponent, int &pow10_exponent) {
(min_exponent + fp::significand_size - 1) * one_over_log2_10));
// Decimal exponent of the first (smallest) cached power of 10.
const int first_dec_exp = -348;
// Difference between two consecutive decimal exponents in cached powers of 10.
// Difference between 2 consecutive decimal exponents in cached powers of 10.
const int dec_exp_step = 8;
index = (index - first_dec_exp - 1) / dec_exp_step + 1;
pow10_exponent = first_dec_exp + index * dec_exp_step;

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@ -2933,7 +2933,7 @@ void basic_writer<Range>::write_double(T value, const format_specs &spec) {
auto dec_pow = internal::get_cached_power(
min_exp - (fp_value.e + internal::fp::significand_size), dec_exp);
internal::fp product = fp_value * dec_pow;
// Generate output.
// Generate output using Grisu digit-gen-mix algorithm.
internal::fp one(1ull << -product.e, product.e);
uint64_t hi = product.f >> -one.e;
uint64_t f = product.f & (one.f - 1);

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@ -39,7 +39,7 @@ for i, exp in enumerate(range(min_exponent, max_exponent + 1, step)):
print('Significands:', end='')
for i, fp in enumerate(powers):
if i % 4 == 0:
if i % 3 == 0:
print(end='\n ')
print(' {:0<#16x}'.format(fp.f, ), end=',')