Split up the CALL_NO_KW and CALL_KW instructions.

[markshannon]

BPO	46329
Nosy	@markshannon, @pablogsal, @brandtbucher, @Fidget-Spinner
PRs	bpo-46329: Split calls into precall and call instructions. #30855 bpo-46329: Fix refleak in specialized isinstance error path #31005 Revert "bpo-46329: Split calls into precall and call instructions." #31011 bpo-46329: Reduce default recursion to 800 if Py_DEBUG is enabled. #31033 bpo-46329: Change calling sequence (again) #31373 bpo-46329: Streamline calling sequence a bit. #31465 bpo-46329: Move call specializations from CALL to PRECALL. #31496 bpo-46329: Fix test failure when Py_STATS is enabled #31511 bpo-46329: Avoid PUSH_NULL when followed by LOAD_GLOBAL #31933

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = 'https://github.com/markshannon'
closed_at = <Date 2022-03-17.16:15:27.117>
created_at = <Date 2022-01-10.12:54:45.748>
labels = ['3.11', 'performance']
title = 'Split up the CALL_NO_KW and CALL_KW instructions.'
updated_at = <Date 2022-03-17.16:15:27.116>
user = 'https://github.com/markshannon'

bugs.python.org fields:

activity = <Date 2022-03-17.16:15:27.116>
actor = 'Mark.Shannon'
assignee = 'Mark.Shannon'
closed = True
closed_date = <Date 2022-03-17.16:15:27.117>
closer = 'Mark.Shannon'
components = []
creation = <Date 2022-01-10.12:54:45.748>
creator = 'Mark.Shannon'
dependencies = []
files = []
hgrepos = []
issue_num = 46329
keywords = ['patch']
message_count = 7.0
messages = ['410209', '411992', '412034', '412089', '413495', '413666', '413783']
nosy_count = 4.0
nosy_names = ['Mark.Shannon', 'pablogsal', 'brandtbucher', 'kj']
pr_nums = ['30855', '31005', '31011', '31033', '31373', '31465', '31496', '31511', '31933']
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'performance'
url = 'https://bugs.python.org/issue46329'
versions = ['Python 3.11']

[markshannon]

Most calls (not those with *args and/or **kwargs) are compiled to the CALL_NO_KW and CALL_KW instructions, possibly with a PRECALL_METHOD prefix.

We want to unify the CALL_NO_KW and CALL_KW instructions into a single CALL instruction and add two new instructions: PRECALL_FUNCTION and KW_NAMES.
All call sequences would start with PRECALL_FUNCTION or PRECALL_METHOD. PRECALL_METHOD would continue to pair with LOAD_METHOD as it does now. PRECALL_FUNCTION would effectively be a no-op, but would be needed to set up internal interpreter variables.

CALL_NO_KW would become CALL and CALL_KW would become KW_NAMES; CALL.

Why?

Specializing calls is an important optimization, but calls are complicated and we want to specialized for both the type of the callable and the shape of the call.

By breaking up calls in this way, we can specialize for the type and for the shape mostly independently.
We can specialize for classes, bound-methods and other objects that ultimately call a Python function in the PRECALL instruction and specialize for the shape of the arguments in the CALL instruction.

See faster-cpython/ideas#210 for more rationale.

[markshannon]

New changeset 89fd7c3 by Mark Shannon in branch 'main':
bpo-46329: Split calls into precall and call instructions. (GH-30855)
89fd7c3

[pablogsal]

Seems that this PR is causing some segfaults. See #30855 (comment)

[pablogsal]

I'm reverting PR30855 for the time being given our buildbot policy.

[markshannon]

New changeset cf345e9 by Mark Shannon in branch 'main':
bpo-46329: Change calling sequence (again) (GH-31373)
cf345e9

[markshannon]

New changeset 59585d6 by Mark Shannon in branch 'main':
bpo-46329: Streamline calling sequence a bit. (GH-31465)
59585d6

[markshannon]

New changeset 424023e by Brandt Bucher in branch 'main':
bpo-46329: Fix test failure when Py_STATS is enabled (GH-31511)
424023e