ruby.git/internal/fixnum.h, branch v3_2_11 The Ruby Programming Language Fix rb_fix_mul_fix on OpenBSD/mips64 2022-07-03T16:42:44+00:00 Jeremy Evans code@jeremyevans.net 2022-07-03T16:42:44+00:00 fe6245b4309c855e6aca5b786ad50a72d53d278a This fixes invalid and inconsistent results for the Fixnum*Fixnum case where the result of the multiplication does not fit in 64-bit on OpenBSD/mips64. For example: $ for x in 1 23; do ruby31 -e 'p(54306000000000*86400)'; done 14409380628474329524 11410664325873689790 Cases where an argument was Bignum, as well as cases where the result of the multiplication fits in 64-bit are fine: $ for x in 1 23; do ruby31 -e 'p(54306000*86400)'; done 4692038400000 4692038400000 $ for x in 1 23; do ruby31 -e 'p(5430600000000000000000*86400)'; done 469203840000000000000000000 469203840000000000000000000 This was originally discovered by running the tests for the openssl gem on OpenBSD/mips64 and having one test fail for a date far in the future. I eventually traced this to the generic multiplication issue. The underlying cause is using the int128_t type. This avoids use of the int128_t type in this case, falling back to the slower conversion code, which in the overflow case, turns the Fixnums into Bignums, then performs the multiplication. 
This fixes invalid and inconsistent results for the Fixnum*Fixnum case
where the result of the multiplication does not fit in 64-bit
on OpenBSD/mips64.  For example:

  $  for x in 1 23; do ruby31 -e 'p(54306000000000*86400)'; done
  14409380628474329524
  11410664325873689790

Cases where an argument was Bignum, as well as cases where the result
of the multiplication fits in 64-bit are fine:

  $ for x in 1 23; do ruby31 -e 'p(54306000*86400)'; done
  4692038400000
  4692038400000

  $ for x in 1 23; do ruby31 -e 'p(5430600000000000000000*86400)'; done
  469203840000000000000000000
  469203840000000000000000000

This was originally discovered by running the tests for the openssl gem
on OpenBSD/mips64 and having one test fail for a date far in the future.
I eventually traced this to the generic multiplication issue.

The underlying cause is using the int128_t type. This avoids use of the
int128_t type in this case, falling back to the slower conversion code,
which in the overflow case, turns the Fixnums into Bignums, then
performs the multiplication.
internal/*.h: skip doxygen 2021-09-10T11:00:06+00:00 卜部昌平 shyouhei@ruby-lang.org 2021-06-08T00:40:43+00:00 daf0c04a47e5aaede2f2a3e3663148dff96ff770 These contents are purely implementation details, not worth appearing in CAPI documents. [ci skip] 
These contents are purely implementation details, not worth appearing in
CAPI documents. [ci skip]
Update fixnum.h 2020-12-01T11:40:33+00:00 jacopo 1753245+intrip@users.noreply.github.com 2020-12-01T11:19:05+00:00 0c57438ccfe394050142171c4d5bba3ae1885534 Fix a typo: "nevative" => "negative" in `rb_fix_plus_fix`. 
Fix a typo: "nevative" => "negative" in `rb_fix_plus_fix`.
 sed -i 's|ruby/impl|ruby/internal|' 2020-05-11T00:24:08+00:00 卜部昌平 shyouhei@ruby-lang.org 2020-05-08T09:31:09+00:00 9e41a75255d15765648279629fd3134cae076398 To fix build failures. 
To fix build failures.
sed -i s|ruby/3|ruby/impl|g 2020-05-11T00:24:08+00:00 卜部昌平 shyouhei@ruby-lang.org 2020-05-04T06:35:26+00:00 d7f4d732c199df24620a162372c71ee83ed21e62 This shall fix compile errors. 
This shall fix compile errors.
add #include guard hack 2020-04-13T07:06:00+00:00 卜部昌平 shyouhei@ruby-lang.org 2020-04-10T05:11:40+00:00 4ff3f205408ff8bb413d69151105d301858136ba According to MSVC manual (*1), cl.exe can skip including a header file when that: - contains #pragma once, or - starts with #ifndef, or - starts with #if ! defined. GCC has a similar trick (*2), but it acts more stricter (e. g. there must be _no tokens_ outside of #ifndef...#endif). Sun C lacked #pragma once for a looong time. Oracle Developer Studio 12.5 finally implemented it, but we cannot assume such recent version. This changeset modifies header files so that each of them include strictly one #ifndef...#endif. I believe this is the most portable way to trigger compiler optimizations. [Bug #16770] *1: https://docs.microsoft.com/en-us/cpp/preprocessor/once *2: https://gcc.gnu.org/onlinedocs/cppinternals/Guard-Macros.html 
According to MSVC manual (*1), cl.exe can skip including a header file
when that:

- contains #pragma once, or
- starts with #ifndef, or
- starts with #if ! defined.

GCC has a similar trick (*2), but it acts more stricter (e. g. there
must be _no tokens_ outside of #ifndef...#endif).

Sun C lacked #pragma once for a looong time.  Oracle Developer Studio
12.5 finally implemented it, but we cannot assume such recent version.

This changeset modifies header files so that each of them include
strictly one #ifndef...#endif.  I believe this is the most portable way
to trigger compiler optimizations. [Bug #16770]

*1: https://docs.microsoft.com/en-us/cpp/preprocessor/once
*2: https://gcc.gnu.org/onlinedocs/cppinternals/Guard-Macros.html
Merge pull request #2991 from shyouhei/ruby.h 2020-04-08T04:28:13+00:00 卜部昌平 shyouhei@ruby-lang.org 2020-04-08T04:28:13+00:00 9e6e39c3512f7a962c44dc3729c98a0f8be90341 Split ruby.h 
Split ruby.h
 internal/fixnum.h rework 2019-12-26T11:45:12+00:00 卜部昌平 shyouhei@ruby-lang.org 2019-12-03T01:48:45+00:00 f6dc053faf6a8850c50638b5e06fca9e878de7ae Add #include lines, move FIXNUM_POSITIVE_P etc. from numeric.h. 
Add #include lines, move FIXNUM_POSITIVE_P etc. from numeric.h.
split internal.h into files 2019-12-26T11:45:12+00:00 卜部昌平 shyouhei@ruby-lang.org 2019-11-29T06:18:34+00:00 b739a63eb41f52d33c33f87ebc44dcf89762cc37 One day, I could not resist the way it was written. I finally started to make the code clean. This changeset is the beginning of a series of housekeeping commits. It is a simple refactoring; split internal.h into files, so that we can divide and concur in the upcoming commits. No lines of codes are either added or removed, except the obvious file headers/footers. The generated binary is identical to the one before. 
One day, I could not resist the way it was written.  I finally started
to make the code clean.  This changeset is the beginning of a series of
housekeeping commits.  It is a simple refactoring; split internal.h into
files, so that we can divide and concur in the upcoming commits.  No
lines of codes are either added or removed, except the obvious file
headers/footers.  The generated binary is identical to the one before.