If we only store the biased pointer, the map ptr region will not
be recognized as reachable memory by leak checkers. This is
primarily problematic for fuzzing, because this is persistent
memory that may be reallocated during the request, without being
an actual leak.
Avoid this by simply storing both the real base pointer of the
allocation, as well as the biased base pointer used for accesses.
Currently, CE_CACHE on strings is only used with opcache interned strings. This
patch extends usage to non-opcache interned strings as well. This means that
most type strings can now make use of CE_CACHE even if opcache is not loaded,
which allows us to remove TYPE_HAS_CE kind, and fix some discrepancies
depending on whether a type stores a resolved or non-resolved name.
There are two cases where CE_CACHE will not be used:
* When opcache is not used and a permanent interned string (that is not an
internal class name) is used as a type name during the request. In this case
we can't allocate a map_ptr index for the permanent string, as it would be
not be in the permanent map_ptr index space.
* When opcache is used but the script is not cached (e.g. eval'd code or
opcache full). If opcache is used, we can't allocate additional map_ptr
indexes at runtime, because they may conflict with indexes allocated by
opcache.
In these two cases we would end up not using CE caching for property types
(argument/return types still have the separate cache slot).
This is generalization of idea, that was previously usesd for caching
resolution of class_entries in zend_type. Now very similar mechanizm is
used for general zend_string into zend_class_entry resolution.
Interned zend_string with IS_STR_CLASS_NAME_MAP_PTR GC_FLAG uses its
refcount to adress corresponding zend_class_entry cache slot.
The refcount keeps an offset to this slot from CG(map_ptr_base).
Flag may be checked by ZSTR_HAS_CE_CACHE(str), cache slot may be read by
ZSTR_GET_CE_CACHE(str) and set by ZSTR_SET_CE_CACHE(str, ce).
This is a new transparent technology that eliminates overhead of PHP class inheritance.
PHP classes are compiled and cached (by opcahce) separately, however their "linking" was done at run-time - on each request. The process of "linking" may involve a number of compatibility checks and borrowing methods/properties/constants form parent and traits. This takes significant time, but the result is the same on each request.
Inheritance Cache performs "linking" for unique set of all the depending classes (parent, interfaces, traits, property types, method types involved into compatibility checks) once and stores result in opcache shared memory. As a part of the this patch, I removed limitations for immutable classes (unresolved constants, typed properties and covariant type checks). So now all classes stored in opcache are "immutable". They may be lazily loaded into process memory, if necessary, but this usually occurs just once (on first linking).
The patch shows 8% improvement on Symphony "Hello World" app.
This patch removes the so called local variables defined per
file basis for certain editors to properly show tab width, and
similar settings. These are mainly used by Vim and Emacs editors
yet with recent changes the once working definitions don't work
anymore in Vim without custom plugins or additional configuration.
Neither are these settings synced across the PHP code base.
A simpler and better approach is EditorConfig and fixing code
using some code style fixing tools in the future instead.
This patch also removes the so called modelines for Vim. Modelines
allow Vim editor specifically to set some editor configuration such as
syntax highlighting, indentation style and tab width to be set in the
first line or the last 5 lines per file basis. Since the php test
files have syntax highlighting already set in most editors properly and
EditorConfig takes care of the indentation settings, this patch removes
these as well for the Vim 6.0 and newer versions.
With the removal of local variables for certain editors such as
Emacs and Vim, the footer is also probably not needed anymore when
creating extensions using ext_skel.php script.
Additionally, Vim modelines for setting php syntax and some editor
settings has been removed from some *.phpt files. All these are
mostly not relevant for phpt files neither work properly in the
middle of the file.
