From an engine perspective, named parameters mainly add three
concepts:
* The SEND_* opcodes now accept a CONST op2, which is the
argument name. For now, it is looked up by linear scan and
runtime cached.
* This may leave UNDEF arguments on the stack. To avoid having
to deal with them in other places, a CHECK_UNDEF_ARGS opcode
is used to either replace them with defaults, or error.
* For variadic functions, EX(extra_named_params) are collected
and need to be freed based on ZEND_CALL_HAS_EXTRA_NAMED_PARAMS.
RFC: https://wiki.php.net/rfc/named_params
Closes GH-5357.
This reverts commit bb43a3822e.
After thinking about this a bit more, this is now going to be
a complete solution for the "readonly properties" case, for example:
unset($foo->readOnly->bar);
should also be legal and
$foo->readOnly['bar'] = 42;
should also be legal if $foo->readOnly is not an array but an
ArrayAccess object.
I think it may be better to distinguish better on the BP_VAR flag
level. Reverting for now.
$a->b->c = 'd';
is now compiled the same way as
$b = $a->b;
$b->c = 'd';
That is, we perform a read fetch on $a->b, rather than a write
fetch.
This is possible, because PHP 8 removed auto-vivification support
for objects, so $a->b->c = 'd' may no longer modify $a->b proper
(i.e. not counting interior mutability of the object).
Closes GH-5250.
Make sure we deref the OBJ_IS result, because we store it in a TMP
var, which is not allowed to contain references and will cause
assertion failures in the unspecialized VM.
This also partially reverts fd463a9a60,
which merged the TMP and VAR specializations of COALESCE to work
around this bug.
An alternative would be to change the result type of OBJ_IS back
to VAR.
RFC: https://wiki.php.net/rfc/null_coalesce_equal_operator
$a ??= $b is $a ?? ($a = $b), with the difference that $a is only
evaluated once, to the degree that this is possible. In particular
in $a[foo()] ?? $b function foo() is only ever called once.
However, the variable access themselves will be reevaluated.
RFC: https://wiki.php.net/rfc/typed_properties_v2
This is a squash of PR #3734, which is a squash of PR #3313.
Co-authored-by: Bob Weinand <bobwei9@hotmail.com>
Co-authored-by: Joe Watkins <krakjoe@php.net>
Co-authored-by: Dmitry Stogov <dmitry@zend.com>
Don't store the live range of the freed variable for FREE_ON_RETURN
frees, instead look it up at runtime. As this is an extremely
unlikely codepath (in particular, it requires a loop variable with
a throwing destructor), saving the runtime lookup of the live range
is not worth the extra complexity this adds everywhere else.