When we change back the bucket key on a class linking failure,
make sure to reload the bucket pointer, as the class table may
have been reallocated in the meantime.
Also remove a bogus bucket key change in anon class registration:
We don't actually rename the class in this case anymore, the RTD
key is already the final name.
In the case where there are still references to an array being iterated
over when the iterator is freed (or the array is not reference counted):
- There's need to save the opline.
- There's no need to check for exceptions.
```
// Before: 0.404 seconds
// After: 0.362 seconds
// loop_iter_empty(1000, 5000);
function loop_iter_empty(int $a, int $b) {
$values = array_fill(0, $b, []);
$total = 0;
for ($i = 0; $i < $b; $i++) {
foreach ($values as $v) {
foreach ($v as $x) {
$total += $x;
}
}
}
return $total;
}
```
And `$x = !$x`
Noticed while working on GH-4912
The included test would not emit undefined variable errors in php 8.0
with opcache enabled. The command used:
```
php -d zend_extension=opcache.so --no-php-ini -d error_reporting=E_ALL \
-d opcache.file_cache= -d opcache.enable_cli=1 test.php
```
Do this by reusing the implementation used for `==`
when both arguments are ints (IS_LONG) or both are floats (IS_DOUBLE)
```php
// Before: nestedloop_ni took 0.442 seconds
// After: nestedloop_ni takes 0.401 seconds (same as nestedloop_ne)
function nestedloop_ni(int $k) {
$x = 0;
for ($i=0; $i < 50000000; $i++) {
if ($i === $k) {
$x++;
}
}
print "$x\n";
}
function nestedloop_ne(int $k) {
$x = 0;
for ($i=0; $i < 50000000; $i++) {
if ($i == $k) {
$x++;
}
}
print "$x\n";
}
```
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.
We are now guaranteed that $this always exists inside methods, as
well as insides closures (if they use $this at all).
This removes checks for $this existence from the individual object
opcodes. Instead ZEND_FETCH_THIS is used in the cases where $this
is not guaranteed to exist, which is mainly the pseudo-main scope.
Closes GH-3822.
Split out the simple equality check into an inline function --
this is one of the common cases.
Replace instanceof_function_ex with zend_class_implements_interface.
There are a few more places where it may be used.
Avoid need of insertion NOP opcoes between unrelated SMART BRANCH instruction and following JMPZ/JMPNZ.
Now instead of checking the opcode of following instruction, the same information is encoded into SMART BRANH result_type.
After fixing the int->double coercion case, this is already verified
at compile-time, so there is no need to redo this type check on
every call.
Only perform the type check every time for the case of AST default
values.
Previously if the "non well formed" notice was converted into an
exception we'd still end up executing the function.
Also drop the now unnecessary EG(exception) checks in the engine.
Additionally remote a bogus exception in zend_is_callable: It
should only be writing to error, but not directly throwing.
It is now only used to signal exceptions for property reads. ERROR
zvals are never returned back to the VM anymore, so there's no
need to check for them when receiving a VAR.
Also return MAY_BE_ERROR, as ERROR is now no longer relevant for
inference.
Weirdly these warnings had zero coverage previously...
Remove an incorrect exception checking optimization: The key
lookup may throw (it could also throw previously, though only
through a custom error handler).
Resources used as array keys are generally handled by throwing a
notice and converting the resource to the resource handle. The only
exception is the [$resource => null] syntax, where this was treated
as an illegal offset type instead. However, this also only happened
for VM evaluations, the AST evaluator did handle resources correctly.
This removes object auto-vivification support.
This also means that we can remove the corresponding special
handling for typed properites: We no longer need to check that a
property is convertible to stdClass if such a conversion might
take place indirectly due to a nested property write.
Additionally OBJ_W style operations now no longer modify the
object operand, and as such we no longer need to treat op1 as a
def in SSA form.
The next step would be to actually compile the whole LHS of OBJ_W
operations in R rather than W mode, but that causes issues with
SimpleXML, whose object handlers depend on the current compilation
structure.
Part of https://wiki.php.net/rfc/engine_warnings.
This switches zend_type from storing a single IS_* type code to
storing a MAY_BE_* type mask. Right now most code still assumes
that there is only a single type in the mask (or two together
with MAY_BE_NULL). But this will make it a lot simpler to introduce
union types.
An additional advantage (and why I'm doing this separately), is
that a number of special cases no longer need to be handled
separately: We can do a single mask & (1 << type) check to handle
all simple types, booleans (true|false) and null.
