bpo-47009: Let PRECALL_NO_KW_LIST_APPEND do its own POP_TOP #32239
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Most code won't do
y = L.append(x)
or whatnot, soPRECALL_NO_KW_LIST_APPEND
is almost always followed byPOP_TOP
. We can verify at specialization time.This saves a
Py_INCREF(Py_None)
, aSET_TOP(Py_None)
, and POP_TOP'sPy_DECREF(POP()); DISPATCH();
.Some microbenchmarks:
From GCC, --enable-optimizations, --with-lto:
https://bugs.python.org/issue47009