According to RFC: https://wiki.php.net/rfc/union_types_v2
The type representation now makes use of both the pointer payload
and the type mask at the same time. Additionall, zend_type_list is
introduced as a new kind of pointer payload, which is used to store
multiple class types. Each of the class types is a tagged pointer,
which may be either a class name or class entry. The latter is only
used for typed properties, while arguments/returns will instead use
cache slots. A type list can contain a mix of both names and CEs at
the same time, as not all classes may be resolvable.
One thing this is missing is support for union types in arginfo
and stubs, which I want to handle separately.
I've also dropped the special object code from the JIT implementation
for now -- I plan to add this back in a different form at a later time.
For now I did not want to include non-trivial JIT changes together
with large functional changes.
Another possible piece of follow-up work is to implement "iterable"
as an internal alias for "array|Traversable". I believe this will
eliminate quite a few special-cases that had to be implemented.
Closes GH-4838.
We now store the pointer payload and the type mask separately. This
is in preparation for union types, where we will be using both at
the same time.
To avoid increasing the size of arginfo structures, the
pass_by_reference and is_variadic fields are now stored as part of
the type_mask (8-bit are reserved for custom use).
Different types of pointer payloads are distinguished based on bits
in the type_mask.
instanceof_function() requires linked classes. I'm not reusing
unlinked_instanceof() here, because it performs class loading,
which wouldn't be right here, I think.
Avoid need of insertion NOP opcoes between unrelated SMART BRANCH instruction and following JMPZ/JMPNZ.
Now instead of checking the opcode of following instruction, the same information is encoded into SMART BRANH result_type.
Many of these now have reflection types,
making the old signatures redundant or inaccurate.
(Some methods also throw Errors instead of returning null/false)
Closes GH-4785.
preg_quote and curl_error now have a non-null return type of `string`.
zend_func_info now duplicates many real reflection types
(some of which are now non-null)
Closes GH-4788.
E.g. hash_equals is outdated - it has a non-null reflection type of bool.
Remove redundant signatures for types that are obviously not reference
counted (`F0`).
Closes GH-4787.
This is limited to types that aren't reference counted.
I assume the info that there is exactly one reference
should be preserved (e.g. for bcsqrt)
Closes GH-4786.
Some of these functions now have real reflection types
and will throw instead of return null/false.
Others provide the exact same reflection type information
that zend_func_info does. (or would after updating outdated types)
Closes GH-4790.
Tyson Andre