parse_constant doesn't get called on 'null', 'true', 'false' since 3.1/2.7.

parse_constant doesn't get called on 'null', 'true', 'false' since 3.1/2.7.

parse_constant doesn't get called on 'null', 'true', 'false' since 3.1/2.7.

when decode astral characters.

when decode astral characters.

when decode astral characters.

when decode astral characters.

when decode astral characters.

(e.g. on Android).

(e.g. on Android).

(e.g. on Android).

empty compile-time PYTHONPATH components.  This fixes some tests in -S or -I
modes.

empty compile-time PYTHONPATH components.  This fixes some tests in -S or -I
modes.

empty compile-time PYTHONPATH components.  This fixes some tests in -S or -I
modes.

When Python is not compiled with PGO, the performance of Python on call_simple
and call_method microbenchmarks depend highly on the code placement. In the
worst case, the performance slowdown can be up to 70%.

The GCC __attribute__((hot)) attribute helps to keep hot code close to reduce
the risk of such major slowdown. This attribute is ignored when Python is
compiled with PGO.

The following functions are considered as hot according to statistics collected
by perf record/perf report:

* _PyEval_EvalFrameDefault()
* call_function()
* _PyFunction_FastCall()
* PyFrame_New()
* frame_dealloc()
* PyErr_Occurred()

It seems like _PyThreadState_UncheckedGet() is not inlined as expected, even
when using gcc -O3.

Patch by Elvis Pranskevichus.

Patch by Elvis Pranskevichus.

Patch by Elvis Pranskevichus.