mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-10-17 12:18:23 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 9

GH-98686: Get rid of "adaptive" and "quick" instructions (GH-99182)

Browse source
This commit is contained in:
Brandt Bucher 2022-11-09 10:50:09 -08:00 • committed by GitHub
parent 6e3cc72afe
commit c7f5708714
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
18 changed files with 562 additions and 758 deletions
Download patch file Download diff file Expand all files Collapse all files

13
Python/adaptive.md
View file

@ -11,7 +11,7 @@ A family of instructions has the following fundamental properties:
generated by the bytecode compiler.
* It has a single adaptive instruction that records an execution count and,
at regular intervals, attempts to specialize itself. If not specializing,
it executes the non-adaptive instruction.
it executes the base implementation.
* It has at least one specialized form of the instruction that is tailored
for a particular value or set of values at runtime.
* All members of the family must have the same number of inline cache entries,
@ -22,19 +22,18 @@ A family of instructions has the following fundamental properties:
The current implementation also requires the following,
although these are not fundamental and may change:
* All families uses one or more inline cache entries,
* All families use one or more inline cache entries,
the first entry is always the counter.
* All instruction names should start with the name of the non-adaptive
* All instruction names should start with the name of the adaptive
instruction.
* The adaptive instruction should end in `_ADAPTIVE`.
* Specialized forms should have names describing their specialization.
## Example family
The `LOAD_GLOBAL` instruction (in Python/ceval.c) already has an adaptive
The `LOAD_GLOBAL` instruction (in Python/bytecodes.c) already has an adaptive
family that serves as a relatively simple example.
The `LOAD_GLOBAL_ADAPTIVE` instruction performs adaptive specialization,
The `LOAD_GLOBAL` instruction performs adaptive specialization,
calling `_Py_Specialize_LoadGlobal()` when the counter reaches zero.
There are two specialized instructions in the family, `LOAD_GLOBAL_MODULE`
@ -138,5 +137,5 @@ to eliminate the branches.
Finally, take care that stats are gather correctly.
After the last `DEOPT_IF` has passed, a hit should be recorded with
`STAT_INC(BASE_INSTRUCTION, hit)`.
After a optimization has been deferred in the `ADAPTIVE` form,
After an optimization has been deferred in the adaptive instruction,
that should be recorded with `STAT_INC(BASE_INSTRUCTION, deferred)`.