* gh-140443:use fma in loghelper to improve accuracy of log for very large integers
Use fused multiply-add in log_helper() for huge ints.
Saving a rounding here is remarkably effective. Across some millions
of randomized test cases with ints up to a billion bits, on Windows
and using log10, the ULP error distribution was dramatically
flattened, and its range was nearly cut in half. In fact, the largest
error Tim saw was under 0.6 ULP.
---------
Co-authored-by: abhi210 <27881020+Abhi210@users.noreply.github.com>
Co-authored-by: Stan Ulbrych <89152624+StanFromIreland@users.noreply.github.com>
* gh-132876: workaround broken ldexp() on Windows 10
ldexp() fails to round subnormal results before Windows 11,
so hide their bug.
Co-authored-by: Tim Peters <tim.peters@gmail.com>
This also reverts loghelper() change in 75f59bb629 for integer
input. The error message shouldn't include argument value here.
Co-authored-by: Victor Stinner <vstinner@python.org>
In the free threaded build, the `_PyObject_LookupSpecial()` call can lead to
reference count contention on the returned function object becuase it
doesn't use stackrefs. Refactor some of the callers to use
`_PyObject_MaybeCallSpecialNoArgs`, which uses stackrefs internally.
This fixes the scaling bottleneck in the "lookup_special" microbenchmark
in `ftscalingbench.py`. However, the are still some uses of
`_PyObject_LookupSpecial()` that need to be addressed in future PRs.
This adds basic support to override default messages for domain errors
in the math_1() helper. The sqrt(), atanh(), log2(), log10() and log()
functions were modified as examples. New macro supports gradual
changing of error messages in other 1-arg functions.
Co-authored-by: CharlieZhao <zhaoyu_hit@qq.com>
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
Move creation of a tuple for var-positional parameter out of
_PyArg_UnpackKeywordsWithVararg().
Merge _PyArg_UnpackKeywordsWithVararg() with _PyArg_UnpackKeywords().
Add a new parameter in _PyArg_UnpackKeywords().
The "parameters" and "converters" attributes of ParseArgsCodeGen no
longer contain the var-positional parameter. It is now available as the
"varpos" attribute. Optimize code generation for var-positional
parameter and reuse the same generating code for functions with and without
keyword parameters.
Add special converters for var-positional parameter. "tuple" represents it as
a Python tuple and "array" represents it as a continuous array of PyObject*.
"object" is a temporary alias of "tuple".
Instead of be limited just by the size of addressable memory (2**63
bytes), Python integers are now also limited by the number of bits, so
the number of bit now always fit in a 64-bit integer.
Both limits are much larger than what might be available in practice,
so it doesn't affect users.
_PyLong_NumBits() and _PyLong_Frexp() are now always successful.
Buildbot failure on Windows 10 with MSC v.1916 64 bit (AMD64):
FAIL: testFmod (test.test_math.MathTests.testFmod)
----------------------------------------------------------------------
Traceback (most recent call last):
File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 605, in testFmod
self.ftest('fmod(-10, 1)', math.fmod(-10, 1), -0.0)
~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "D:\buildarea\3.x.bolen-windows10\build\Lib\test\test_math.py", line 258, in ftest
self.fail("{}: {}".format(name, failure))
~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: fmod(-10, 1): expected -0.0, got 0.0 (zero has wrong sign)
Here Windows loose sign of the result; if y is nonzero, the result
should have the same sign as x.
This amends commit 28aea5d07d.
This PR adds the ability to enable the GIL if it was disabled at
interpreter startup, and modifies the multi-phase module initialization
path to enable the GIL when loading a module, unless that module's spec
includes a slot indicating it can run safely without the GIL.
PEP 703 called the constant for the slot `Py_mod_gil_not_used`; I went
with `Py_MOD_GIL_NOT_USED` for consistency with gh-104148.
A warning will be issued up to once per interpreter for the first
GIL-using module that is loaded. If `-v` is given, a shorter message
will be printed to stderr every time a GIL-using module is loaded
(including the first one that issues a warning).
- input checks for math_1(L989), math_1a(L1023), math_2(L1064,L1071), hypot(L2682), log(L2307), ldexp(L2168), ceil(L1165), floor(L1236,L1239) and dist(L2587,L2588,L2628).
- drop inaccessible "if" branch (L3518) in perm_comb_small()
- improve fsum coverage for exceptional cases (L1433,L1438,L1451,L1497), ditto fmod(L2378)
- rewrite modf to fix inaccessible case(L2229), ditto for pow(L2988)
(all line numbers are wrt the main branch at 5e6661bce9)
Move these private functions to the internal C API
(pycore_abstract.h):
* _Py_convert_optional_to_ssize_t()
* _PyNumber_Index()
Argument Clinic now emits #include "pycore_abstract.h" when these
functions are used.
The parser of the c-analyzer tool now uses a list of files which use
the limited C API, rather than a list of files using the internal C
API.
This PR updates `math.nextafter` to add a new `steps` argument. The behaviour is as though `math.nextafter` had been called `steps` times in succession.
---------
Co-authored-by: Mark Dickinson <mdickinson@enthought.com>
This PR removes `_Py_dg_stdnan` and `_Py_dg_infinity` in favour of
using the standard `NAN` and `INFINITY` macros provided by C99.
This change has the side-effect of fixing a bug on MIPS where the
hard-coded value used by `_Py_dg_stdnan` gave a signalling NaN
rather than a quiet NaN.
---------
Co-authored-by: Mark Dickinson <dickinsm@gmail.com>
Here we are doing no more than adding the value for Py_mod_multiple_interpreters and using it for stdlib modules. We will start checking for it in gh-104206 (once PyInterpreterState.ceval.own_gil is added in gh-104204).
* Eliminate all remaining uses of Py_SIZE and Py_SET_SIZE on PyLongObject, adding asserts.
* Change layout of size/sign bits in longobject to support future addition of immortal ints and tagged medium ints.
* Add functions to hide some internals of long object, and for setting sign and digit count.
* Replace uses of IS_MEDIUM_VALUE macro with _PyLong_IsCompact().
`math_1_to_whatever()` is no longer useful, since all existing uses of it convert to `float`.
Earlier versions of Python used `math_1_to_whatever` with an integer target; see
gh-16991 for the PR where that use was removed.
