The aim of this PR is twofold:
- Reduce the number of highly similar TMP|VAR handlers
- Avoid ZVAL_DEREF in most of these cases
This is achieved by guaranteeing that all zend_compile_expr() calls, as well as
all other compile calls with BP_VAR_{R,IS}, will result in a TMP variable. This
implies that the result will not contain an IS_INDIRECT or IS_REFERENCE value,
which was mostly already the case, with two exceptions:
- Calls to return-by-reference functions. Because return-by-reference functions
are quite rare, this is solved by delegating the DEREF to the RETURN_BY_REF
handler, which will examine the stack to check whether the caller expects a
VAR or TMP to understand whether the DEREF is needed. Internal functions will
also need to adjust by calling the zend_return_unwrap_ref() function.
- By-reference assignments, including both $a = &$b, as well as $a = [&$b]. When
the result of these expressions is used in a BP_VAR_R context, the reference
is unwrapped via a ZEND_QM_ASSIGN opcode beforehand. This is exceptionally
rare.
Closes GH-20628
This is a quick fix for the problem.
It'll work while all the JIT-ed functions have the same "fixed stack frame".
Unwinder uses hard-coded unwind data for this "fixed stack frame".
* Preallocate space for Win64 shadow args
* typo
* Setup unwinder for JIT functions
* Revert "Dynamically xfail test case which fails on CI"
This reverts commit 7cc327fd5a.
* Revert "Dynamically xfail test case which fails on CI"
This reverts commit bdde797159.
* Revert "Dynamically xfail test cases which fail on CI (GH-15710)"
This reverts commit 6d5962074f.
* Remove XFAIL sections
* Add hard-coded SEH unwind data for EXITCALL
* Fix unwind data
* Fix Windows multi-process support
* Typo
Adding a stack check here as I consider serialization to be a more
sensitive place where erroring out with an exception seems appropriate.
Closes GH-16159.
Increase the reserved stack size in ASAN builds, as instrumentation use more stack.
Increase the max allowed stack size in some tests, and enable these tests under ASAN.
Use __builtin_frame_address(0), instead of some stack variable, when we need a stack address, as ASAN may store local variables outside of the real stack.
for threaded context, it solely uses a new api only available on
illumos.
Here using a common older api to get the stack info for the current
thread.
while at it, completing stack_limit_010 test for these platforms.
Stack overflows can be detected as long as C stack frames between two
execute_ex() calls use less than zend.reserved_stack_size bytes of stack.
The default value of zend.reserved_stack_size accounts for the largest stack
users, but MSAN instrumentation increases usage considerably: php_pcre2_match
uses more than 200KiB of stack in some MSAN build, compared to 20KiB without MSAN
according to -fstack-usage.