installing LLVM can be found in the `JIT compiler documentation
<https://github.com/python/cpython/blob/main/Tools/jit/README.md>`__
for all supported platforms.
-
(Contributed by Savannah Ostrowski in :gh:`140973`.)
.. rubric:: A new tracing frontend
supported. This was made possible by an overhauled JIT tracing frontend
that records actual execution paths through code, rather than estimating
them as the previous implementation did.
-
(Contributed by Ken Jin in :gh:`139109`. Support for Windows added by
Mark Shannon in :gh:`141703`.)
optimizer. This allows the JIT compiler to avoid certain stack operations
altogether and instead operate on registers. This allows the JIT to produce
more efficient traces by avoiding reads and writes to memory.
-
(Contributed by Mark Shannon in :gh:`135379`.)
.. rubric:: More JIT optimizations
More `constant-propagation <https://en.wikipedia.org/wiki/Constant_folding>`__
is now performed. This means when the JIT compiler detects that certain user
code results in constants, the code can be simplified by the JIT.
-
(Contributed by Ken Jin and Savannah Ostrowski in :gh:`132732`.)
-The JIT avoids :term:`reference count`\ s where possible. This generally
+:term:`Reference count`\ s are avoided whenever it is safe to do so. This generally
reduces the cost of most operations in Python.
-
(Contributed by Ken Jin, Donghee Na, Zheao Li, Hai Zhu, Savannah Ostrowski,
Reiden Ong, Noam Cohen, Tomas Roun, PuQing, Cajetan Rodrigues, and Sacul in :gh:`134584`.)
+The JIT optimizer now supports significantly more operations than in 3.14.
+(Contributed by Kumar Aditya, Ken Jin, and Sacul in :gh:`131798`.)
+
.. rubric:: Better machine code generation
The JIT compiler's machine code generator now produces better machine code
for x86-64 and AArch64 macOS and Linux targets. In general, users should
experience lower memory usage for generated machine code and more efficient
-machine code versus the old JIT.
-
+machine code versus 3.14.
(Contributed by Brandt Bucher in :gh:`136528` and :gh:`136528`.
Implementation for AArch64 contributed by Mark Shannon in :gh:`139855`.
Additional optimizations for AArch64 contributed by Mark Shannon and
Diego Russo in :gh:`140683` and :gh:`142305`.)
+.. rubric:: Maintainability
+
+The JIT optimizer's operations have been simplified.
+This was made possible by a refactoring of JIT data structures.
+(Contributed by Zhongtian Zheng in :gh:`148211` and Hai Zhu in :gh:`143421`.)
+
Removed
========