Fixes GH-8646
See https://github.com/php/php-src/issues/8646 for thorough discussion.
Interned strings that hold class entries can get a corresponding slot in map_ptr for the CE cache.
map_ptr works like a bump allocator: there is a counter which increases to allocate the next slot in the map.
For class name strings in non-opcache we have:
- on startup: permanent + interned
- on request: interned
For class name strings in opcache we have:
- on startup: permanent + interned
- on request: either not interned at all, which we can ignore because they won't get a CE cache entry
or they were already permanent + interned
or we get a new permanent + interned string in the opcache persistence code
Notice that the map_ptr layout always has the permanent strings first, and the request strings after.
In non-opcache, a request string may get a slot in map_ptr, and that interned request string
gets destroyed at the end of the request. The corresponding map_ptr slot can thereafter never be used again.
This causes map_ptr to keep reallocating to larger and larger sizes.
We solve it as follows:
We can check whether we had any interned request strings, which only happens in non-opcache.
If we have any, we reset map_ptr to the last permanent string.
We can't lose any permanent strings because of map_ptr's layout.
Closes GH-10783.
This reverts commit d0527427be.
This patch makes Swoole/Swow can not work anymore, because Coroutine will yield to another one during socket operation, EG(record_errors) assertion will always fail, and zend_begin_record_errors() was only used during compile time before.
Note: zend_emit_recorded_errors() and the typo fix are reserved.
This is not actually related to SSL handshake but stream socket creation
which does not clean errors if the error handler is set. This fix
prevents emitting errors until the stream is freed.
==109253== 280 (56 direct, 224 indirect) bytes in 1 blocks are definitely lost in loss record 4 of 4
==109253== at 0x483B7F3: malloc (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
==109253== by 0x6D9FA2: __zend_malloc (zend_alloc.c:3068)
==109253== by 0x745138: zend_add_attribute (zend_attributes.c:226)
==109253== by 0x6680D1: zend_add_parameter_attribute (zend_attributes.h:102)
==109253== by 0x66B787: zm_startup_zend_test (test.c:478)
==109253== by 0x7224CD: zend_startup_module_ex (zend_API.c:2202)
==109253== by 0x72252C: zend_startup_module_zval (zend_API.c:2217)
==109253== by 0x734288: zend_hash_apply (zend_hash.c:2011)
==109253== by 0x722C30: zend_startup_modules (zend_API.c:2328)
==109253== by 0x67409B: php_module_startup (main.c:2256)
==109253== by 0x88EDDE: php_cli_startup (php_cli.c:409)
==109253== by 0x890F61: main (php_cli.c:1334)
This is achieved by tracking the observers on the run_time_cache (with a fixed amount of slots, 2 for each observer).
That way round, if the run_time_cache is freed all associated observer data is as well.
This approach has been chosen, as to avoid any ABI or API breakage.
Future versions may for example choose to provide a hookable API for run_time_cache freeing or similar.
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).
Currently, classes that can't be linked get moved back into the original script
and are not preloaded. As such classes may be referenced from functions that
did get preloaded, there is a preload autoload mechanism to load them at
runtime.
Since PHP 8.1, we can safely preload unlinked classes, which will then go
through usual lazy loading. This means that we no longer need the preload
autoload mechanism. However, we need to be careful not to modify any hash
table buckets in-place, and should create new buckets for lazy loaded classes.
Having all property types resolved is no longer a hard requirement
for preloading, resolving the types is just an optimization. As
such, drop the special logic that forced loading of property
types when include-based preloading is used. Instead only keep
the code that resolves types based on actually preloaded classes.
Also drop the ZEND_ACC_PROPERTY_TYPES_RESOLVED flag, which is now
nearly useless and takes up flag space...
This removes switching to main for fatal errors in fibers in favor of catching any zend_bailout in a fiber and calling zend_bailout again after switching to the previous fiber or {main}.
Userland property infos are no longer duplicated since PHP 7.4, when we
stopped setting SHADOW flags on inherited private properties. Stop duplicating
internal property infos as well.
This requires switching class destruction to work in reverse order, as child
classes may be reusing structures from parent classes, and as such should be
destroyed first.
Since 3e6b447979 it is again possible to have
warnings (deprecations) during inheritance, and more such functionality is
likely in the future. This is a problem, because such warnings will only be
shown on the first request if the opcache inheritance cache is used. This
currently causes test failures in --repeat builds.
Fix this by uplifting the error recording functionality from opcache to Zend,
and then using it to persist a warning trace in the inheritance cache, which
can then be used to replay the warnings on subsequent executions.
As debug_print_backtrace() is not performance-critical, this
implements it by formatting the zend_fetch_backtrace() result.
This means there is only one place implementing the backtrace
construction logic, and they cannot go out of sync.
zend_fetch_backtrace() has much better test coverage, because
it is used by exceptions.
Closes GH-6869.
This PR corrects misspellings identified by the check-spelling action.
The misspellings have been reported at jsoref@b6ba3e2#commitcomment-48946465
The action reports that the changes in this PR would make it happy: jsoref@602417c
Closes GH-6822.
Currently, dynamically declared functions and closures are inserted
into the function table under a runtime definition key, and then later
possibly renamed. When opcache is not used and a file containing a
closure is repeatedly included, this leads to a very large memory leak,
as the no longer needed closure declarations will never be freed
(https://bugs.php.net/bug.php?id=76982).
With this patch, dynamic functions are instead stored in a
dynamic_func_defs member on the op_array, which opcodes reference
by index. When the parent op_array is destroyed, the dynamic_func_defs
it contains are also destroyed (unless they are stilled used elsewhere,
e.g. because they have been bound, or are used by a live closure). This
resolves the fundamental part of the leak, though doesn't completely
fix it yet due to some arena allocations.
The main non-obvious change here is to static variable handling:
We can't destroy static_variables_ptr in destroy_op_array, as e.g.
that would clear the static variables in a dynamic function when
the op_array containing it is destroyed. Static variable destruction
is separated out for this reason (we already do static variable
destruction separately for normal functions, so we only need to
handle main scripts).
Closes GH-5595.
Some upcoming changes like https://wiki.php.net/rfc/deprecate_null_to_scalar_internal_arg
will make it somewhat inconvenient to determine whether a given
function invocation will generate a diagnostic. Rather than trying
to exclude this in advance, call the function with diagnostics
suppressed, and check whether anything was thrown.
This adds a new EG flag that is kept specific to the SCCP use-case.
This does not use the error_cb hook as it is a (non-TLS) global,
and doesn't fully suppress error handling besides.
Test this by removing the in advance checks for implode and array_flip.
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 only moves the files, adjusts the build system, exports APIs
and does minor fixups to make sure the code builds.
This does not yet try to make the optimizer usable independently
of opcache.
Closes GH-6642.
We're starting to see a mix between uses of zend_bool and bool.
Replace all usages with the standard bool type everywhere.
Of course, zend_bool is retained as an alias.
This restricts allowed usage of $GLOBALS, with the effect that
plain PHP arrays can no longer contain INDIRECT elements.
RFC: https://wiki.php.net/rfc/restrict_globals_usage
Closes GH-6487.