Tracing JIT support for indirect CV modification (may be incomplete)

Fixed retutn type inference when return undefined variable

Fixed tracing JIT register allocator (failure on ext/opcache/tests/jit/assign_002.phpt)

Allow tracing JIT generate code when function exits from VM (e.g. for magic __get/__set)

Don't add guards that are not going to be checked

Fixed use-after-free in tracing JIT when recording closures and top-level op_arrays.

Fixed tracing JIT type inference for passing undefined CV by value

Fixed incorrect trace type inference for top-level code

Add a side exit on enter to function if it may be called with different number of arguments.

Fixed tracing JIT support for ZEND_RETURN_BY_REF in CALL VM

Set proper jit_extension for inherited methods

Fixed JIT for integer overflow checks

Fixed tracing JIT for RETRUN $undefined_cv

Keep trace number in EG(jit_trace_num) instead of EG(reserved)[zend_func_info_rid]

Reorder conditions to save one instruction in recursive return loop

Allow counter settings to be "zero" to disable corresponding counter

Tracing JIT SHM data initilaizarion must be done at MINIT

Make number of root and side traces configurable

Make JIT parameters configurable through opcache.jit_... options

Wrong condition

Tracing JIT with -O1 doesn't need to do type inference and abstract stack maintaining

func_info should be empty

JIT refactoring to allow run-time changes of JIT options (triggers, optimization_level, debug flags, etc)

Tracing JIT support for delayed call chain

Set "hybrid_ret_counters" only after links to "function entry" traces.