Any update?
Thanks and Regards, Markus Am 30.07.24 um 09:56 schrieb Jonathan Wakely:
On Tue, 30 Jul 2024, 06:21 Ehrnsperger, Markus, <markus_ehrnsper...@yahoo.de> wrote:On 2024-07-29 12:16, Jonathan Wakely wrote: > On Mon, 29 Jul 2024 at 10:45, Jonathan Wakely <jwakely....@gmail.com> wrote: >> On Mon, 29 Jul 2024 at 09:42, Ehrnsperger, Markus >> <markus_ehrnsper...@yahoo.de> wrote: >>> Hi, >>> >>> >>> I'm attaching two files: >>> >>> 1.: to_chars10.h: >>> >>> This is intended to be included in libstdc++ / gcc to achieve performance improvements. It is an implementation of >>> >>> to_chars10(char* first, char* last, /* integer-type */ value); >>> >>> Parameters are identical to std::to_chars(char* first, char* last, /* integer-type */ value, int base = 10 ); . It only works for base == 10. >>> >>> If it is included in libstdc++, to_chars10(...) could be renamed to std::to_chars(char* first, char* last, /* integer-type */ value) to provide an overload for the default base = 10 >> Thanks for the email. This isn't in the form of a patch that we can >> accept as-is, although I see that the license is compatible with >> libstdc++, so if you are looking to contribute it then that could be >> done either by assigning copyright to the FSF or under the DCO terms. >> See https://gcc.gnu.org/contribute.html#legal for more details. >> >> I haven't looked at the code in detail, but is it a similar approach >> to https://jk-jeon.github.io/posts/2022/02/jeaiii-algorithm/ ? >> How does it compare to the performance of that algorithm? >> >> I have an incomplete implementation of that algorithm for libstdc++ >> somewhere, but I haven't looked at it for a while. > I took a closer look and the reinterpret_casts worried me, so I tried > your test code with UBsan. There are a number of errors that would > need to be fixed before we would consider using this code. Attached are new versions of to_chars10.cpp, to_chars10.h and the new file itoa_better_y.h Thanks! I'll take another look. Changes: - I removed all reinterpret_casts, and tested with -fsanitize=undefined - I added itoa_better_y.h from https://jk-jeon.github.io/posts/2022/02/jeaiii-algorithm/ to the performance test. Note: There is only one line in the benchmark test for itoa_better_y due to limited features of itoa_better_y: Benchmarking random unsigned 32 bit itoa_better_y ... to_chars10.h: Signed-off-by: Markus Ehrnsperger <markus_ehrnsper...@yahoo.de> The other files are only for performance tests. > > >> >>> 2.: to_chars10.cpp: >>> >>> This is a test program for to_chars10 verifying the correctness of the results, and measuring the performance. The actual performance improvement is system dependent, so please test on your own system. >>> >>> On my system the performance improvement is about factor two, my results are: >>> >>> >>> Test int8_t verifying to_chars10 = std::to_chars ... OK >>> Test uint8_t verifying to_chars10 = std::to_chars ... OK >>> Test int16_t verifying to_chars10 = std::to_chars ... OK >>> Test uint16_t verifying to_chars10 = std::to_chars ... OK >>> Test int32_t verifying to_chars10 = std::to_chars ... OK >>> Test uint32_t verifying to_chars10 = std::to_chars ... OK >>> Test int64_t verifying to_chars10 = std::to_chars ... OK >>> Test uint64_t verifying to_chars10 = std::to_chars ... OK >>> >>> Benchmarking test case tested method ... time (lower is better) >>> Benchmarking random unsigned 64 bit to_chars10 ... 0.00957 >>> Benchmarking random unsigned 64 bit std::to_chars ... 0.01854 >>> Benchmarking random signed 64 bit to_chars10 ... 0.01018 >>> Benchmarking random signed 64 bit std::to_chars ... 0.02297 >>> Benchmarking random unsigned 32 bit to_chars10 ... 0.00620 >>> Benchmarking random unsigned 32 bit std::to_chars ... 0.01275 >>> Benchmarking random signed 32 bit to_chars10 ... 0.00783 >>> Benchmarking random signed 32 bit std::to_chars ... 0.01606 >>> Benchmarking random unsigned 16 bit to_chars10 ... 0.00536 >>> Benchmarking random unsigned 16 bit std::to_chars ... 0.00871 >>> Benchmarking random signed 16 bit to_chars10 ... 0.00664 >>> Benchmarking random signed 16 bit std::to_chars ... 0.01154 >>> Benchmarking random unsigned 08 bit to_chars10 ... 0.00393 >>> Benchmarking random unsigned 08 bit std::to_chars ... 0.00626 >>> Benchmarking random signed 08 bit to_chars10 ... 0.00465 >>> Benchmarking random signed 08 bit std::to_chars ... 0.01089 >>> >>> >>> Thanks, Markus >>> >>> >>>
