Make all jump opcodes relative

[iritkatriel]

BPO	47120
Nosy	@markshannon, @corona10, @brandtbucher, @iritkatriel
PRs	bpo-47120: Replace the JUMP_ABSOLUTE opcode by the relative JUMP_BACKWARD #32115 gh-91276: Make JUMP_IF_TRUE_OR_POP/JUMP_IF_FALSE_OR_POP relative #32215 bpo-47120: make JUMP_NO_INTERRUPT relative #32221 bpo-47120: define virtual opcodes in opcode.py. Better organization of jump opcodes. #32353 bpo-47120: make POP_JUMP_IF_NONE/NOT_NONE relative #32359 bpo-47120: make POP_JUMP_IF_TRUE/FALSE/NONE/NOT_NONE relative #32400

^{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/iritkatriel'
closed_at = None
created_at = <Date 2022-03-25.14:30:53.931>
labels = ['interpreter-core', '3.11', 'performance']
title = 'Make all jump opcodes relative'
updated_at = <Date 2022-04-07.14:59:34.889>
user = 'https://github.com/iritkatriel'

bugs.python.org fields:

activity = <Date 2022-04-07.14:59:34.889>
actor = 'iritkatriel'
assignee = 'iritkatriel'
closed = False
closed_date = None
closer = None
components = ['Interpreter Core']
creation = <Date 2022-03-25.14:30:53.931>
creator = 'iritkatriel'
dependencies = []
files = []
hgrepos = []
issue_num = 47120
keywords = ['patch']
message_count = 4.0
messages = ['416003', '416431', '416466', '416772']
nosy_count = 4.0
nosy_names = ['Mark.Shannon', 'corona10', 'brandtbucher', 'iritkatriel']
pr_nums = ['32115', '32215', '32221', '32353', '32359', '32400']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = 'performance'
url = 'https://bugs.python.org/issue47120'
versions = ['Python 3.11']

Linked PRs

• gh-91276: remove unused _PyOpcode_RelativeJump #103156

[iritkatriel]

For some of our jump opcodes target is absolute, so it can easily require EXTENDED_ARGS. Our analysis [1] shows that turning all absolute jumps into relative jumps will eliminate almost all EXTENDED_ARGS on jumps.

This will require a _BACK version for each jump type, which negates the oparg.

[1] faster-cpython/ideas#235 (reply in thread)

[markshannon]

New changeset a00518d by Irit Katriel in branch 'main':
bpo-47120: Replace the JUMP_ABSOLUTE opcode by the relative JUMP_BACKWARD (GH-32115)
a00518d

[brandtbucher]

Another benefit of this work is that we'll be able to remove first_instr from the eval loop.

[iritkatriel]

New changeset 0aa8d5c by Irit Katriel in branch 'main':
bpo-47120: make JUMP_NO_INTERRUPT relative (GH-32221)
0aa8d5c

[iritkatriel]

This is complete.