'tbnz/tbz' instruction can be used to check whether a given W or X
register value is negative or positive.
For example,
```
tst x0, x0
blt >1
```
can be optimized as `tbnz x0, #63, >1`
It's important to note that the jump range of 'tbnz/tbz' is limited, and
it's better NOT to use 'tbnz/tbz' if the target of 'b.cond' is a label
in section .cold_code or a global label, such as the instruction
sequence `tst RETVALw, RETVALw; blt ->trace_halt` at function
zend_jit_trace_exit_stub(), and the instruction sequence `tst REG0,
REG0; blt >7` at function zend_jit_incdec_obj().
Minor updates:
Use macros BW_OP_32_WITH_CONST and GC_ADDREF at function
zend_jit_push_call_frame().
Change-Id: I1597609bdabf55ea2f9d24528e7a037bc3e5c3a1
ac80aeb3ac