intrinsics.c: CALL_INTRINSIC dispatch

Python/intrinsics.c implements the bodies called by the CALL_INTRINSIC_1 and CALL_INTRINSIC_2 bytecodes. These instructions replace what were previously inline opcode sequences for import-star, print() during interactive use, type-alias creation, and similar one-off operations that do not fit neatly into the normal call convention.

Map

Lines	Symbol	Role
1-40	includes	Dependencies on ceval.h, import.h, typevarobject.h
41-80	_PyIntrinsics_UnaryFunctions[]	Table of unary intrinsic function pointers
81-120	_PyIntrinsics_BinaryFunctions[]	Table of binary intrinsic function pointers
121-170	intrinsic_print	Interactive print for PRINT_EXPR replacement
171-220	intrinsic_import_star	from mod import * expansion
221-270	intrinsic_stopiteration_error	Raise StopIteration from generator return value
271-320	intrinsic_typevar_with_bound	TypeVar with upper bound (PEP 695)
321-360	intrinsic_typevar_with_constraints	TypeVar with constraint tuple
361-400	3.14 additions (intrinsic_unary_positive, intrinsic_set_function_type_params)	New in 3.14

Reading

Dispatch tables

The two tables are simple C arrays of instrinsicfunc1 / instrinsicfunc2 function pointers indexed by the oparg of CALL_INTRINSIC_1 or CALL_INTRINSIC_2. The ceval loop just does:

case CALL_INTRINSIC_1: {
    PyObject *res = _PyIntrinsics_UnaryFunctions[oparg](tstate, value);
    ...
}

Index 0 is reserved as an error sentinel so that an unrecognised oparg produces a clear SystemError rather than a crash.

intrinsic_import_star

This is the most complex unary intrinsic. It calls _PyObject_GetAttrId to fetch __all__ when present, then falls back to iterating over all names that do not start with an underscore. The result is merged into the caller's locals dict via PyDict_SetItem.

static PyObject *
intrinsic_import_star(PyThreadState *tstate, PyObject *frommod)
{
    PyObject *all = _PyObject_GetAttrIdWithoutError(frommod, &PyId___all__);
    /* If __all__ missing, enumerate public names from __dict__. */
    ...
}

3.14 additions

3.14 adds intrinsic_unary_positive (oparg INTRINSIC_UNARY_POSITIVE) to replace the UNARY_POSITIVE opcode that was removed from the specialising interpreter. It calls PyNumber_Positive. intrinsic_set_function_type_params supports the PEP 695 generic syntax by calling _Py_set_function_type_params on the callable.

gopy notes

• vm/eval_gen.go dispatches CALL_INTRINSIC_1 and CALL_INTRINSIC_2 through Go switch statements rather than function-pointer tables.
• intrinsic_import_star is ported in vm/eval_import.go alongside the IMPORT_NAME and IMPORT_FROM handlers.
• intrinsic_typevar_with_bound and intrinsic_typevar_with_constraints are not yet ported; TypeVar support is planned for a later milestone.
• The 3.14 intrinsic_unary_positive path is handled directly in the switch arm rather than as a separate function.