Generator functions have to specify the * (asterix) modifier after the
function keyword. If they do so the ZEND_ACC_GENERATOR flag is added to
the fn_flags.
. zend_function.pass_rest_by_reference is replaced by
ZEND_ACC_PASS_REST_BY_REFERENCE in zend_function.fn_flags
. zend_function.return_reference is replaced by ZEND_ACC_RETURN_REFERENCE
in zend_function.fn_flags
. zend_arg_info.required_num_args removed. it was needed only for internal
functions. Now the first arg_info for internal function (which has special
meaning) is represented by zend_internal_function_info structure.
. zend_op_array.size, size_var, size_literal, current_brk_cont,
backpatch_count moved into CG(context), because they are used only during
compilation.
. zend_op_array.start_op is moved into EG(start_op), because it's used
only for 'interactive' execution of single top-level op-array.
. zend_op_array.done_pass_two is replaced by ZEND_ACC_DONE_PASS_TWO in
zend_op_array.fn_flags.
. op_array.vars array is trimmed (reallocated) during pass_two.
. zend_class_entry.constants_updated is replaced by
ZEND_ACC_CONSTANTS_UPDATED in zend_class_entry.ce_flags
. the size of zend_class_entry is reduced by sharing the same memory space
by different information for internal and user classes.
See zend_class_inttry.info union.
# RFC http://wiki.php.net/rfc/horizontalreuse#traits_-_reuse_of_behavior
# Ok, here we go, I guess that will result in more discussion, which is fine
# by me. But now, the patch is here, and properly archived.
#
# See below a list of notes to the patch, it also includes a list of
# points which should be fixed
#
# Internals of the Traits Patch
# -----------------------------
#
# Open TODOs
# """"""""""
#
# - Reflection API
# - support for traits for internal classes
# - currently destroy_zend_class does not handle that case
#
# Introduced Structures
# """""""""""""""""""""
#
# Data structures to encode the composition information specified in the
# source:
# - zend_trait_method_reference
# - zend_trait_precedence
# - zend_trait_alias
#
# Changes
# """""""
#
# zend_class_entry
# - uses NULL terminated lists of pointers for
# - trait_aliases
# - trait_precedences
# - do you prefer an explicit counter?
# - the information is only necessary during class composition
# but might be interesting for reflection
# - did not want to blow up class further with not really necessary length counters
#
# added keywords
# - trait
# - insteadof
#
# Added opcodes
# ZEND_ADD_TRAIT
# - similar to ZEND_ADD_INTERFACE
# - adds the trait to the list of traits of a class, no actual composition done
# ZEND_BIND_TRAITS
# - emitted in zend_do_end_class_declaration
# - concludes the class definition and will initiate the trait composition
# when the class definition is encountered during runtime
#
# Added Flags
# ZEND_ACC_TRAIT = 0x120
# ZEND_ACC_IMPLEMENT_TRAITS = 0x400000
# ZEND_FETCH_CLASS_TRAIT = 14
#
# zend_vm_execute.h
# - not sure whether the handler initialization (ZEND_ADD_TRAIT_SPEC_HANDLER,
# ZEND_BIND_TRAITS_SPEC_HANDLER) is correct, maybe it should be more selective
#
# zend_compile.c
# - refactored do_inherit_method_check
# split into do_inherit_method_check and do_inheritance_check_on_method
# - added helper functions use a '_' as prefix and are not mentioned in the
# headers
# - _copy_functions
# prepare hash-maps of functions which should be merged into a class
# here the aliases are handled
# - _merge_functions
# builds a hash-table of the methods which need to be added to a class
# does the conflict detection
# - reused php_runkit_function_copy_ctor
# - it is not identical with the original code anymore, needed to update it
# think I fixed some bugs, not sure whether all have been reported back to runkit
# - has to be renamed, left the name for the moment, to make its origin obvious
# - here might be optimization potential
# - not sure whether everything needs to be copied
# - copying the literals might be broken
# - added it since the literals array is freed by efree and gave problems
# with doubled frees
# - all immutable parts of the zend_op array should not be copied
# - am not sure which parts are immutable
# - and not sure how to avoid doubled frees on the same arrays on shutdown
# - _merge_functions_to_class
# does the final merging with the target class to handle inherited
# and overridden methods
# - small helper for NULL terminated lists
# zend_init_list, zend_add_to_list
#
# zend_language_parser.y
# - reused class definition for traits
# - there should be something with regard to properties
# - if they get explicitly defined, it might be worthwhile to
# check that there are no collisions with other traits in a composition
# (however, I would not introduce elaborate language features to control that
# but a notice for such conflicts might be nice to the developers)
. ZEND_RECV now always has IS_CV as its result
. ZEND_CATCH now has to be used only with constant class names
. ZEND_FETCH_DIM_? may fetch array and dimension operans in a different order
. Improved syntax highlighting and consistency for variables in double-quoted strings and literal text in HEREDOCs and backticks. (Matt)
. Optimized interpolated strings to use one less opcode. (Matt)
- Renamed zend_do_fetch_class_name() to zend_do_build_full_name() (It is not used only for classes)
- Moved zend_resolve_class_name prototype to zend_compile.h
The following pseudo-code explains how it should be used in opcode cache.
function cache_compile_file($filename) {
if (!is_cached($filename)) {
...
orig_compiler_options = CG(compiler_optins);
CG(compiler_options) |= ZEND_COMPILE_IGNORE_INTERNAL_CLASSES |
ZEND_COMPILE_DELAYED_BINDING;
$op_array = orig_compile_file($filename);
CG(compiler_options) = orig_copiler_options;
...
} else {
$op_array = restore_from_cache($filename);
}
zend_do_delayed_early_binding($op_array);
}
- Fixed bug #36214 (__get method works properly only when conditional operator is used).
- Fixed bug #39449 (Overloaded array properties do not work correctly).
- Fixed bug #39990 (Cannot "foreach" over overloaded properties).
# This time i added:
# ZEND_FE_RESET_VARIABLE
# ZEND_FE_RESET_REFERENCE
# and dapted parser,compiler,executor,interfaces to handle these flags
# their purpose is to be able to pass whetehr foreach is done by ref to
# the current() handler so that it can error out in case it is not capable
# to comply to the requested return signature/protocol/semantics (weyp).
determine whether pass by ref is possible or pass by value is needed.
# This is usefull when functions take array or string parameters as
# expressions. In such a case force by ref is not applicable and the
# executor would copy the variable unnecessarily as soon as it is at least
# once referenced.
- Extensions which delete global variables need to use new special function
- delete_global_variable() (I'm about to rename it) to remove them.
- Will post to internals@ or via commit messages if there's anything else.
a) We specialize opcodes according to op_type fields. Each opcode has to
be marked with which op_type's it uses.
b) We support different execution methods. Function handlers, switch()
and goto dispatching. goto seems to be the fastest but it really
depends on the compiler and how well it optimizes. I suggest playing
around with optimization flags.
- Warning: Things might break so keep us posted on how things are going.
(Dmitry, Andi)
- Add infrastructure for built-in functions to hint whether they
return by reference or not. It is NOT currently used for anything,
except for interface prototypes (you can use it to request that the
function that implements your prototype returns by reference or
doesn't return by reference).
For downwards compatibility - by default, interface prototypes are
agnostic as to whether the function that implements them returns
by reference or not. Use ZEND_BEGIN_ARG_INFO_EX() with
ZEND_RETURN_VALUE/ZEND_RETURN_REFERENCE to change that.
- Fix ArrayAccess::getOffset() to conduct additional checks.
If your getOffset() should work with multidimensional arrays - it
must return by reference.
Note that this is available for downwards compatibility only - and it doesn't
work if you use new features (namely, interfaces). Generally, people should
declare their classes before using them, but we just didn't want hell to break
loose (c)
implementation, and allows exceptions to 'fire' much earlier than before.
Instructions on how to use the new mechanism will follow on internals@
shortly...
Note - this (most probably) breaks the current implementation of
set_exception_handler()
implementation.
Using clone directly is now done using
$replica = clone $src;
Clone methods must now be declared as follows:
function __clone($that)
{
}
Clone methods in derived classes can call the __clone method of their parent
classes using parent::__clone($that)
internal non-static methods statically.
# As discussed with Zeev:
# - For BC standard userspace methods allow this with an E_STRICT message.
# - If you want to implement an internal method taht can be called both
# statically and non-statically then use flag ZEND_ACC_ALLOW_STATIC.
# - Magic user space methods __*() cannot and __construct, __destruct,
# __clone can never be called statically.
add E_STRICT warnings in case you return something by reference that you're
not supposed to (anything that's not a variable, or a return-value of a
function that returned by reference).
- Use this to prevent memleaks when an exception gets thrown in ctors.
# I added the dtor flags for consistency, atm a compareable check in
# isn't necessary for destruction. But anyway i'll use this for the
# Relection API too.
including:
- Whether or not to pass by ref (replaces the old arg_types, with arg_info)
- Argument name (for future use, maybe introspection)
- Class/Interface name (for type hints)
- If a class/interface name is available, whether to allow a null instance
Both user and builtin functions share the same data structures.
To declare a builtin function that expects its first arg to be an instance
of class 'Person', its second argument as a regular arg, and its third by
reference, use:
ZEND_BEGIN_ARG_INFO(my_func_arg_info, 0)
ZEND_ARG_OBJ_INFO(0, someone, Person, 1)
ZEND_ARG_PASS_INFO(0)
ZEND_ARG_PASS_INFO(1)
ZEND_END_ARG_INFO();
and use my_func_arg_info as the arg_info parameter to the ZEND_FE() family
of macros.
The first arg to each ZEND_ARG_*() macro is whether or not to pass by ref.
The boolean arg to ZEND_BEGIN_ARG_INFO() tells the engine whether to treat
the arguments for which there's no explicit information as pass by reference
or not.
The boolean argument to ZEND_ARG_OBJ_INFO() (4th arg) is whether or not to allownull values.
- The fields of zend_namespace were not completely initialized which
led to a variety of problems.
- The occurrence of class/interface/namespace definition is now
captured.
- Functions/classes/interfaces/namespaces can be preceded by doc
comments which are stored for use by extensions.
avoid making developers traverse the entire class/interface hierarchy
before they can figure out whether a class is instantiable
(ok, so it makes sense :)
1. Nested classes are gone.
2. New syntax for namespaces:
namespace foo {
class X { ... }
function bar { ... }
var x = 1;
const ZZ = 2;
}
3. Namespaced symbol access: $x = new foo::X; - etc.
For now, namespaces are case insensitive, just like classes.
Also, there can be no global class and namespace with the same name
(to avoid ambiguities in :: resolution).
We need separate cleanup stage because of the following problem:
Suppose we destroy class X, which destroys function table,
and in function table we have function foo() that has static $bar. Now if
object of class X was assigned to $bar, its destructor will be called and will
fail since X's function table is in mid-destruction.
So we want first of all to clean up all data and then move to tables
destruction.
Note that only run-time accessed data need to be cleaned up, pre-defined
data can not contain objects and thus are not probelmatic.
# Looks like we are having a lots of pain in the various parts of the body
# because of the destructors...
This opcode is not executeable but only holds data for opcodes
that need more than two arguments (presently only ASSIGN_OBJ and the ilk but
in the future also ASSIGN_DIM)
NOTE: This only works at the syntax level right now (parser). It
doesn't actually work as of yet - all statics are considered
public for now
- Prevent users from putting more restrictions on methods in derived classes
(i.e., you cannot make a public method private in a derived class, etc.)
- Implement abstract methods, syntax:
- abstract function foo($vars);
- I don't see any reason why modifiers such as static/public need to be
- used with abstract. PHP is weakly typed and there would be no meaning to
- this anyway. People who want a strictly typed compiled language are
- looking in the wrong place.
This should work as follows: if class hasn't member with given name,
__get/__set is called. If class has no method with given name, __call is called.
__get/__set are not recursive, __call can be.
- global function information because it wasn't available. We have to do
- an additional assignment per-function call so that it'll be available.
- Also don't define the global scope as function name _main_ but leave it
- empty so that frameworks like Pear can decide what they want to do.
- understand why Java didn't do so.
- If you still want to control destruction of your object then either make
- sure you kill all references or create a destruction method which you
- call yourself.
There are still a few problems such as includes and calling other functions
from internal functions which aren't seen (will have to think if and how to
fix this).
Also the main scripts filename isn't available. Need to think about that.
- It isn't complete yet but I want to work on it from another machine. It
- shouldn't break anything else so just don't try and use it.
- The following is a teaser of something that already works:
<?php
class MyClass
{
function hello()
{
print "Hello, World\n";
}
class MyClass2
{
function hello()
{
print "Hello, World in MyClass2\n";
}
}
}
import function hello, class MyClass2 from MyClass;
MyClass2::hello();
hello();
?>
- freeing objects from id 0 instead of id 1. id 0 is not used.
- Change isset/empty opcodes to support static members and the new way of
- doing $this->foobar. Also the opcodes operate now on the hash table
- combined with the variable names so that they can be overloaded by the
- soon to be added overloading patch.