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GH-139757: JIT: Remove redundant branches to jumps in the assembly optimizer (GH-140800)

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JIT: Remove redundant branches to jump in the assembly optimizer

* Refactor JIT assembly optimizer making instructions instances not just strings
* Remove redundant jumps and branches where legal to do so
* Modifies _BINARY_OP_SUBSCR_STR_INT to avoid excessive inlining depth
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Mark Shannon 2025-12-08 17:57:11 +00:00 • committed by GitHub
parent 37988c57ea
commit e0451ceef8
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8 changed files with 220 additions and 74 deletions
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7
Python/bytecodes.c
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@ -982,9 +982,10 @@ dummy_func(
DEOPT_IF(!_PyLong_IsNonNegativeCompact((PyLongObject *)sub));
Py_ssize_t index = ((PyLongObject*)sub)->long_value.ob_digit[0];
DEOPT_IF(PyUnicode_GET_LENGTH(str) <= index);
// Specialize for reading an ASCII character from any string:
Py_UCS4 c = PyUnicode_READ_CHAR(str, index);
DEOPT_IF(Py_ARRAY_LENGTH(_Py_SINGLETON(strings).ascii) <= c);
// Specialize for reading an ASCII character from an ASCII string:
DEOPT_IF(!PyUnicode_IS_COMPACT_ASCII(str));
uint8_t c = PyUnicode_1BYTE_DATA(str)[index];
assert(c < 128);
STAT_INC(BINARY_OP, hit);
PyObject *res_o = (PyObject*)&_Py_SINGLETON(strings).ascii[c];
PyStackRef_CLOSE_SPECIALIZED(sub_st, _PyLong_ExactDealloc);