When the JIT defers the IS_UNDEF check for FETCH_OBJ_R to the result
type guard, the deoptimization escape path dispatches to opline->handler
via the trace_escape stub. If opline->handler has been overwritten with
JIT code (e.g. a function entry trace), this creates an infinite loop.
Fix by dispatching to the original VM handler (orig_handler from the
trace extension) instead of going through the trace_escape stub. This
avoids the extra IS_UNDEF guard on every property read while correctly
handling the rare IS_UNDEF case during deoptimization.
Also set current_op_array in zend_jit_trace_exit_to_vm so that the
blacklisted exit deoptimizer can resolve orig_handler, covering the
case where side trace compilation is exhausted.
Closes GH-21368.
Insert type guards (CHECK_OP1_TRACE_TYPE / CHECK_OP2_TRACE_TYPE) on the
sensitive bailout paths in ADD/SUB/MUL JIT compilation: the MAY_BE_UNDEF
and non-numeric operand breaks. Guards are only emitted when the traced
operand type is IS_LONG or IS_DOUBLE, ensuring TSSA result type
predictions stay valid for side traces without affecting the normal
numeric fast path.
Fixes GH-20838
Co-authored-by: Dmitry Stogov <dmitrystogov@gmail.com>
When FE_RESET_RW executes, it converts the CV to a reference before
checking if the array/object is empty. However, when the JIT creates
exit points for FE_RESET_RW in zend_jit_trace_handler(), it wasn't
updating the stack type for op1 to reflect this change.
This caused side traces compiled from these exit points to have
incorrect type information. The side trace's CV cleanup code would
see IS_OBJECT and generate a direct call to zend_objects_store_del(),
but the actual value was a zend_reference*, causing a segfault.
The fix adds ZEND_FE_RESET_RW to the list of opcodes that temporarily
set their op1 stack type to IS_UNKNOWN before creating exit points.
This follows the same pattern used for ZEND_BIND_INIT_STATIC_OR_JMP.
When IS_UNKNOWN, the JIT falls back to SSA type info which correctly
includes MAY_BE_REF for FE_RESET_RW's op1_def.
Fixes GH-20818
Closes GH-20948
This is similar to f6c2e40a11 but for minimal JIT + tracing JIT.
Most of the times the tracing JIT shouldn't rely on going to the VM, but
in some cases, like in minimal JIT, it can and then it hits the same
bug.
Closes GH-20897.
The arg_info member of zend_function is now always a zend_arg_info*. Before,
it was a zend_internal_arg_info* on internal functions, unless the
ZEND_ACC_USER_ARG_INFO flag was set.
Closes GH-19022
The dynamic loader, starting around version 1284, patches the thunk emitted for
thread local variables by the compiler, so that its format changes from
struct Thunk {
void *func;
size_t module;
size_t offset;
}
to
struct Thunk_v2 {
void *func;
uint32_t module;
uint32_t offset;
// other fields
}
which has the same size, but not the same layout.
This is mentionned in
9307719dd8/libdyld/ThreadLocalVariables.h (L90)
As a result, access to thread specific variables in JIT is broken.
Fix by using the new layout when the new dynamic loader is in use.
Closes GH-20121
