Method emit_dec_ref

mypyc/codegen/emit.py:611–645

Decrement reference count of C expression `dest`. For composite unboxed structures (e.g. tuples) recursively decrement reference counts for each component. If rare is True, optimize for code size and compilation speed.

(
        self, dest: str, rtype: RType, *, is_xdec: bool = False, rare: bool = False
    )

        # Otherwise assume it's an unboxed, pointerless value and do nothing.

    def emit_dec_ref(
        self, dest: str, rtype: RType, *, is_xdec: bool = False, rare: bool = False
    ) -> None:
        """Decrement reference count of C expression `dest`.

        For composite unboxed structures (e.g. tuples) recursively
        decrement reference counts for each component.

        If rare is True, optimize for code size and compilation speed.
        """
        x = "X" if is_xdec else ""
        if is_int_rprimitive(rtype):
            if rare:
                self.emit_line(f"CPyTagged_{x}DecRef({dest});")
            else:
                # Inlined
                self.emit_line(f"CPyTagged_{x}DECREF({dest});")
        elif isinstance(rtype, RTuple):
            for i, item_type in enumerate(rtype.types):
                self.emit_dec_ref(f"{dest}.f{i}", item_type, is_xdec=is_xdec, rare=rare)
        elif isinstance(rtype, RVec):
            prefix = VEC_MACRO_PREFIX[rtype._ctype]
            self.emit_line(f"{prefix}_DECREF({dest});")
        elif not rtype.is_unboxed:
            if rare:
                self.emit_line(f"CPy_{x}DecRef({dest});")
            else:
                # Inlined
                if rtype.may_be_immortal or not HAVE_IMMORTAL:
                    self.emit_line(f"CPy_{x}DECREF({dest});")
                else:
                    self.emit_line(f"CPy_{x}DECREF_NO_IMM({dest});")
        elif rtype.is_refcounted:
            assert False, f"dec_ref not implemented for {rtype}"
        # Otherwise assume it's an unboxed, pointerless value and do nothing.

    def pretty_name(self, typ: RType) -> str:
        value_type = optional_value_type(typ)