the main idea - the smaller the zend_op structure, the lees memory traffic is required to load VM instructions during execution. The patch reduces the size of each opcode from 48 to 32 bytes (saves 16 bytes for each opcode, and applications use thousands of opoceds). This reduced the number of CPU cache misses by 12% and improved performance of real-life apps by 1-2%.
The patch affects how constants and jump targets are represented in VM during execution. Previously they were implemented as absolute 64-bit pointers. Now they are relative 32-bit offsets.
In run-time constant now should be accessed as:
RT_CONSTANT(op_array, opine->op1) instead of opline->op1.zv
EX_CONSTANT(opline->op1) instead of opline->op1.zv
Jump targets:
OP_JMP_ADDR(opline, opline->op2) instead of opline->op2.jmp_addr
The patch doesn't change zend_op representation for 32-bit systems. They still use absolute addresses. The compile-time representation is also kept the same.
* coalesce_operator:
Extended coalesce operator test case for ordering/short-circuiting
Ensure not evaluated twice
Added test
Initial coalesce operator implementation
As far as I can discern these are leftovers of the interactive
shell implementation that was used before PHP 5.4. Now the readline
ext makes use of normal eval calls for this.
So, dropping these until there is evidence to the contrary, as they
currently wouldn't work anyway.
* master:
fix nmake snap when ext name is different in target dll
force atoll macro usage on windows
Enable $ replacement in exif, ldap, pdo_pgsql and tidy
See bug #67635
NEWS
NEWS
improve previous, add message during configure
Fixed bug #67635 php links to systemd libraries without using pkg-config
Improve fix for #66608
Fixed segfault with empty break
New added opcodes don't need to be resloved
Update NEWS
Update NEWS
Update NEWS
Fixed bug #66827 Session raises E_NOTICE when session name variable is array
implemented copy libs of core exts in phpize mode
fix copy the ext dll into the prefix path in phpize mode
fix default prefix in phpize mode
fix file with zero size usage in phpize mode
Conflicts:
Zend/zend_opcode.c
Zend/zend_vm_def.h
Zend/zend_vm_execute.h
ext/session/session.c
In PHP-5.6 and below each argument passed to user function was copies on VM stack twice.
Now we always have ZEND_INIT_FCALL (or simular) opcode that pushes "call frame" on top of VM stack.
"Call frame" is actually the same zend_execute_data structure.
All the following ZEND_SEND instructions push arguments on top of the stack in a way that they directly comes into corresponding CV variables of the called frame. Extra arguments are copied at the end of stack frame (after all CV and TMP variables) on function enterance.
There are two minor incompatibilities:
1) It's not allowed to decalre functions redefining arguments e.g. "function foo($a,$a) {}".
2) func_get_arg() and func_get args() return the current value of argument and not the original value that was sent.
It should be accessed using Z_CACHE_SLOT() macro.
zend_literal structure is removed.
API functions that accepted pointer to zend_literal now accept pointer to zval or cache_slot directly.
Calls of such functiond that now accept cache_slot need to be changed to pass -1 instead of NULL.
