'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
Move the dual_it_free call from the dtor_obj into the free_obj
handler, allowing us to drop the dtor_obj handler entirely. This
exposes another leak in bug65387.phpt, which is addressed by
adding more GC roots in the get_gc handler.
Moving the zend_iterator_dtor from dual_it_dtor to dual_it_free_storage
exposed this GC leak in an existing test. Forward the result of the
iterator get_gc to the dual_it get_gc.
When doing a non finishing flush, BZ2_bzCompress() returns BZ_FLUSH_OK
(not BZ_FINISH_OK) what requires us to do further flushes right away.
We also refactor the while-loop as do-loop.
Closes GH-7113.
When the memory limit is restored during shutdown, we may still
be using a lot of memory. Ignore the failure at that point and
set it again after the MM is shut down, at which point memory
usage should be at its lowest point.
MSVC doesn't support __attribute__((unused)), so this can cause
a lot of warnings for extensions. Use the (void) trick instead.
However, this requires us to initialize the variable as well,
to ensure that ubsan does not read a trap representation.
Updates the deprecation message for implicit incompatible float to int conversion from:
```
Implicit conversion from non-compatible float %.*H to int in %s on line %d
```
to
```
Implicit conversion from float %.*H to int loses precision in %s on line %d
```
Related: #6661
This macro is a footgun because it creates an uninitialized array
(only an allocation). This macro is no longer used in php-src,
and we have better alternatives like array_init() or
ZVAL_ARR(arr, zend_new_array(size_hint)).
One shift instruction can be saved if 'shifted register' is used.
It's worth noting that the destination register of previous shift
instruction doesn't hold the shift result any longer now. And we have to
guarantee that 'shifted register' mode is applied to all the use sites
of this destination register.
Besides, several code-style issues are fixed.
Change-Id: I8bcdd092253d342d383732a926512e761e453808
The way to fix it is to disable certain match start optimizaions. The
observed performance impact appears negligible ATM, compared to the
functional regression revealed.
A possible side effect might occur if a pattern uses (*COMMIT) or
(*MARK), which is however not a very broadly used syntax in PHP. Still
this should be observed and handled by possibly adding a possibility to
reverse PCRE2_NO_START_OPTIMIZE on the user side.
One test shows a behavior change, where instead of int 0 the match
would produce an error and return false. Except strict comparison
is used, this should be acceptable.
Signed-off-by: Anatol Belski <ab@php.net>
Allows flags besides ZEND_FIBER_FLAG_THREW to be set without causing this method to throw.
The method will not be called after a bailout, so the ZEND_FIBER_FLAG_BAILOUT case was removed.
The following warning message would be produced for macOS on Apple
silicon.
```
php-src/ext/opcache/jit/zend_jit_arm64.dasc:15356:79: warning: incompatible pointer types passing 'ptrdiff_t *' (aka 'long *') to parameter of type 'int64_t *'
(aka 'long long *') [-Wincompatible-pointer-types]
const char *name = zend_jit_disasm_find_symbol((ptrdiff_t)cp + offset - 4, &offset);
^~~~~~~
ext/opcache/jit/zend_jit_disasm.c:210:58: note: passing argument to parameter 'offset' here
int64_t *offset) {
^
```
Flag -Wincompatible-pointer-types is enabled by default in Clang [1],
but not in GCC [2].
Adding explicit type conversion would remove this warning.
[1]
https://releases.llvm.org/10.0.0/tools/clang/docs/DiagnosticsReference.html#wincompatible-pointer-types
[2]
https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Warning-Options.html#Warning-Options
Change-Id: Ia0777a5731ba8f0764e232c0d47aeaab076d13f5
- perform constant shift by single instruction
TODO: DynAsm: can't encode "lsl x0, x0, #var" !!!
- avoid usage of REG1 for variable shift (it was x86 limitation)
- enable register reuse for SL/SR instructions
- remove special scratch register handling for SL/SR (it was x86
limitation)
- Remove need for extra scratch registers. AArch64 JIT backend
don't use extra register for constants. It uses reserved TMP
registers.
Nikita Popov