void frame::follow_roots() {
if (is_interpreted_frame()) {
if (has_interpreted_float_marker() && follow_roots_interpreted_float_frame()) return;
// Follow the roots of the frame
for (oop* p = sp(); p <= temp_addr(0); p++) {
MarkSweep::follow_root(p);
}
MarkSweep::follow_root((oop*)hp_addr());
MarkSweep::follow_root(receiver_addr());
return;
}
if (is_compiled_frame()) {
if (has_compiled_float_marker() && follow_roots_compiled_float_frame()) return;
for (oop* p = sp(); p < (oop*)fp(); p++) MarkSweep::follow_root(p);
return;
}
if (is_entry_frame()) {
for (oop* p = sp(); p < (oop*)fp(); p++) MarkSweep::follow_root(p);
return;
}
if (is_deoptimized_frame()) {
// Expression stack
oop* end = (oop*)fp() + frame_real_sender_sp_offset;
for (oop* p = sp(); p < end; p++) MarkSweep::follow_root(p);
MarkSweep::follow_root((oop*)frame_array_addr());
return;
}
}
frame frame::sender(RegisterMap* map) const {
// Default is not to follow arguments; the various
// sender_for_xxx methods update this accordingly.
map->set_include_argument_oops(false);
if (is_entry_frame())
return sender_for_entry_frame(map);
else
return sender_for_nonentry_frame(map);
}
frame frame::sender(RegisterMap* map) const {
assert(map != NULL, "map must be set");
assert(CodeCache::find_blob_unsafe(_pc) == _cb, "inconsistent");
// Default is not to follow arguments; update it accordingly below
map->set_include_argument_oops(false);
if (is_entry_frame()) return sender_for_entry_frame(map);
intptr_t* younger_sp = sp();
intptr_t* sp = sender_sp();
// Note: The version of this operation on any platform with callee-save
// registers must update the register map (if not null).
// In order to do this correctly, the various subtypes of
// of frame (interpreted, compiled, glue, native),
// must be distinguished. There is no need on SPARC for
// such distinctions, because all callee-save registers are
// preserved for all frames via SPARC-specific mechanisms.
//
// *** HOWEVER, *** if and when we make any floating-point
// registers callee-saved, then we will have to copy over
// the RegisterMap update logic from the Intel code.
// The constructor of the sender must know whether this frame is interpreted so it can set the
// sender's _sp_adjustment_by_callee field. An osr adapter frame was originally
// interpreted but its pc is in the code cache (for c1 -> osr_frame_return_id stub), so it must be
// explicitly recognized.
if (is_ricochet_frame()) return sender_for_ricochet_frame(map);
bool frame_is_interpreted = is_interpreted_frame();
if (frame_is_interpreted) {
map->make_integer_regs_unsaved();
map->shift_window(sp, younger_sp);
} else if (_cb != NULL) {
// Update the locations of implicitly saved registers to be their
// addresses in the register save area.
// For %o registers, the addresses of %i registers in the next younger
// frame are used.
map->shift_window(sp, younger_sp);
if (map->update_map()) {
// Tell GC to use argument oopmaps for some runtime stubs that need it.
// For C1, the runtime stub might not have oop maps, so set this flag
// outside of update_register_map.
map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
if (_cb->oop_maps() != NULL) {
OopMapSet::update_register_map(this, map);
}
}
}
return frame(sp, younger_sp, frame_is_interpreted);
}
frame frame::sender() const {
frame result;
if (is_entry_frame()) {
// Delta frame called from C; skip all C frames and return top C
// frame of that chunk as the sender
assert(has_next_Delta_fp(), "next Delta fp must be non zero");
assert(next_Delta_fp() > _fp, "must be above this frame on stack");
result = frame(next_Delta_sp(), next_Delta_fp());
} else if (is_deoptimized_frame()) {
result = frame(real_sender_sp(), link(), return_addr());
} else {
result = frame(sender_sp(), link(), return_addr());
}
return result;
}
//------------------------------------------------------------------------------
// frame::sender
frame frame::sender(RegisterMap* map) const {
// Default is we done have to follow them. The sender_for_xxx will
// update it accordingly
map->set_include_argument_oops(false);
if (is_entry_frame()) return sender_for_entry_frame(map);
if (is_interpreted_frame()) return sender_for_interpreter_frame(map);
assert(_cb == CodeCache::find_blob(pc()),"Must be the same");
if (_cb != NULL) {
return sender_for_compiled_frame(map);
}
// Must be native-compiled frame, i.e. the marshaling code for native
// methods that exists in the core system.
return frame(sender_sp(), link(), sender_pc());
}
void frame::oop_iterate(OopClosure* blk) {
if (is_interpreted_frame()) {
if (has_interpreted_float_marker() && oop_iterate_interpreted_float_frame(blk)) return;
// lprintf("Frame: fp = %#lx, sp = %#lx]\n", fp(), sp());
for (oop* p = sp(); p <= temp_addr(0); p++) {
// lprintf("\t[%#lx]: ", p);
// (*p)->short_print();
// lprintf("\n");
blk->do_oop(p);
}
// lprintf("\t{%#lx}: ", receiver_addr());
// (*receiver_addr())->short_print();
// lprintf("\n");
blk->do_oop(receiver_addr());
return;
}
if (is_compiled_frame()) {
if (has_compiled_float_marker() && oop_iterate_compiled_float_frame(blk)) return;
// All oops are [sp..fp[
for (oop* p = sp(); p < (oop*)fp(); p++) {
blk->do_oop(p);
}
return;
}
if (is_entry_frame()) {
// All oops are [sp..fp[
for (oop* p = sp(); p < (oop*)fp(); p++) {
blk->do_oop(p);
}
return;
}
if (is_deoptimized_frame()) {
// Expression stack
oop* end = (oop*)fp() + frame_real_sender_sp_offset;
// All oops are [sp..end[
for (oop* p = sp(); p < end; p++) {
blk->do_oop(p);
}
blk->do_oop((oop*)frame_array_addr());
return;
}
}
void frame::describe_pd(FrameValues& values, int frame_no) {
if (is_interpreted_frame()) {
DESCRIBE_FP_OFFSET(interpreter_frame_sender_sp);
DESCRIBE_FP_OFFSET(interpreter_frame_last_sp);
DESCRIBE_FP_OFFSET(interpreter_frame_method);
DESCRIBE_FP_OFFSET(interpreter_frame_mdx);
DESCRIBE_FP_OFFSET(interpreter_frame_cache);
DESCRIBE_FP_OFFSET(interpreter_frame_locals);
DESCRIBE_FP_OFFSET(interpreter_frame_bcx);
DESCRIBE_FP_OFFSET(interpreter_frame_initial_sp);
} else if (is_entry_frame()) {
// This could be more descriptive if we use the enum in
// stubGenerator to map to real names but it's most important to
// claim these frame slots so the error checking works.
for (int i = 0; i < entry_frame_after_call_words; i++) {
values.describe(frame_no, fp() - i, err_msg("call_stub word fp - %d", i));
}
}
}
bool frame::safe_for_sender(JavaThread *thread) {
address sp = (address)_sp;
address fp = (address)_fp;
address unextended_sp = (address)_unextended_sp;
// consider stack guards when trying to determine "safe" stack pointers
static size_t stack_guard_size = os::uses_stack_guard_pages() ? (StackYellowPages + StackRedPages) * os::vm_page_size() : 0;
size_t usable_stack_size = thread->stack_size() - stack_guard_size;
// sp must be within the usable part of the stack (not in guards)
bool sp_safe = (sp < thread->stack_base()) &&
(sp >= thread->stack_base() - usable_stack_size);
if (!sp_safe) {
return false;
}
// unextended sp must be within the stack and above or equal sp
bool unextended_sp_safe = (unextended_sp < thread->stack_base()) &&
(unextended_sp >= sp);
if (!unextended_sp_safe) {
return false;
}
// an fp must be within the stack and above (but not equal) sp
// second evaluation on fp+ is added to handle situation where fp is -1
bool fp_safe = (fp < thread->stack_base() && (fp > sp) && (((fp + (return_addr_offset * sizeof(void*))) < thread->stack_base())));
// We know sp/unextended_sp are safe only fp is questionable here
// If the current frame is known to the code cache then we can attempt to
// to construct the sender and do some validation of it. This goes a long way
// toward eliminating issues when we get in frame construction code
if (_cb != NULL ) {
// First check if frame is complete and tester is reliable
// Unfortunately we can only check frame complete for runtime stubs and nmethod
// other generic buffer blobs are more problematic so we just assume they are
// ok. adapter blobs never have a frame complete and are never ok.
if (!_cb->is_frame_complete_at(_pc)) {
if (_cb->is_nmethod() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
return false;
}
}
// Could just be some random pointer within the codeBlob
if (!_cb->code_contains(_pc)) {
return false;
}
// Entry frame checks
if (is_entry_frame()) {
// an entry frame must have a valid fp.
if (!fp_safe) return false;
// Validate the JavaCallWrapper an entry frame must have
address jcw = (address)entry_frame_call_wrapper();
bool jcw_safe = (jcw < thread->stack_base()) && ( jcw > fp);
return jcw_safe;
}
intptr_t* sender_sp = NULL;
address sender_pc = NULL;
if (is_interpreted_frame()) {
// fp must be safe
if (!fp_safe) {
return false;
}
sender_pc = (address) this->fp()[return_addr_offset];
sender_sp = (intptr_t*) addr_at(sender_sp_offset);
} else {
// must be some sort of compiled/runtime frame
// fp does not have to be safe (although it could be check for c1?)
// check for a valid frame_size, otherwise we are unlikely to get a valid sender_pc
if (_cb->frame_size() <= 0) {
return false;
}
sender_sp = _unextended_sp + _cb->frame_size();
// On Intel the return_address is always the word on the stack
sender_pc = (address) *(sender_sp-1);
}
// If the potential sender is the interpreter then we can do some more checking
if (Interpreter::contains(sender_pc)) {
// ebp is always saved in a recognizable place in any code we generate. However
// only if the sender is interpreted/call_stub (c1 too?) are we certain that the saved ebp
// is really a frame pointer.
intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset);
bool saved_fp_safe = ((address)saved_fp < thread->stack_base()) && (saved_fp > sender_sp);
if (!saved_fp_safe) {
return false;
}
// construct the potential sender
frame sender(sender_sp, saved_fp, sender_pc);
return sender.is_interpreted_frame_valid(thread);
}
// We must always be able to find a recognizable pc
CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
if (sender_pc == NULL || sender_blob == NULL) {
return false;
}
// Could be a zombie method
if (sender_blob->is_zombie() || sender_blob->is_unloaded()) {
return false;
}
// Could just be some random pointer within the codeBlob
if (!sender_blob->code_contains(sender_pc)) {
return false;
}
// We should never be able to see an adapter if the current frame is something from code cache
if (sender_blob->is_adapter_blob()) {
return false;
}
// Could be the call_stub
if (StubRoutines::returns_to_call_stub(sender_pc)) {
intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset);
bool saved_fp_safe = ((address)saved_fp < thread->stack_base()) && (saved_fp > sender_sp);
if (!saved_fp_safe) {
return false;
}
// construct the potential sender
frame sender(sender_sp, saved_fp, sender_pc);
// Validate the JavaCallWrapper an entry frame must have
address jcw = (address)sender.entry_frame_call_wrapper();
bool jcw_safe = (jcw < thread->stack_base()) && ( jcw > (address)sender.fp());
return jcw_safe;
}
if (sender_blob->is_nmethod()) {
nmethod* nm = sender_blob->as_nmethod_or_null();
if (nm != NULL) {
if (nm->is_deopt_mh_entry(sender_pc) || nm->is_deopt_entry(sender_pc)) {
return false;
}
}
}
// If the frame size is 0 something (or less) is bad because every nmethod has a non-zero frame size
// because the return address counts against the callee's frame.
if (sender_blob->frame_size() <= 0) {
assert(!sender_blob->is_nmethod(), "should count return address at least");
return false;
}
// We should never be able to see anything here except an nmethod. If something in the
// code cache (current frame) is called by an entity within the code cache that entity
// should not be anything but the call stub (already covered), the interpreter (already covered)
// or an nmethod.
if (!sender_blob->is_nmethod()) {
return false;
}
// Could put some more validation for the potential non-interpreted sender
// frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
// One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
// We've validated the potential sender that would be created
return true;
}
// Must be native-compiled frame. Since sender will try and use fp to find
// linkages it must be safe
if (!fp_safe) {
return false;
}
// Will the pc we fetch be non-zero (which we'll find at the oldest frame)
if ( (address) this->fp()[return_addr_offset] == NULL) return false;
// could try and do some more potential verification of native frame if we could think of some...
return true;
}
bool frame::safe_for_sender(JavaThread *thread) {
address _SP = (address) sp();
address _FP = (address) fp();
address _UNEXTENDED_SP = (address) unextended_sp();
// sp must be within the stack
bool sp_safe = (_SP <= thread->stack_base()) &&
(_SP >= thread->stack_base() - thread->stack_size());
if (!sp_safe) {
return false;
}
// unextended sp must be within the stack and above or equal sp
bool unextended_sp_safe = (_UNEXTENDED_SP <= thread->stack_base()) &&
(_UNEXTENDED_SP >= _SP);
if (!unextended_sp_safe) return false;
// an fp must be within the stack and above (but not equal) sp
bool fp_safe = (_FP <= thread->stack_base()) &&
(_FP > _SP);
// We know sp/unextended_sp are safe only fp is questionable here
// If the current frame is known to the code cache then we can attempt to
// to construct the sender and do some validation of it. This goes a long way
// toward eliminating issues when we get in frame construction code
if (_cb != NULL ) {
// First check if frame is complete and tester is reliable
// Unfortunately we can only check frame complete for runtime stubs and nmethod
// other generic buffer blobs are more problematic so we just assume they are
// ok. adapter blobs never have a frame complete and are never ok.
if (!_cb->is_frame_complete_at(_pc)) {
if (_cb->is_nmethod() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
return false;
}
}
// Entry frame checks
if (is_entry_frame()) {
// an entry frame must have a valid fp.
if (!fp_safe) {
return false;
}
// Validate the JavaCallWrapper an entry frame must have
address jcw = (address)entry_frame_call_wrapper();
bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > _FP);
return jcw_safe;
}
intptr_t* younger_sp = sp();
intptr_t* _SENDER_SP = sender_sp(); // sender is actually just _FP
bool adjusted_stack = is_interpreted_frame();
address sender_pc = (address)younger_sp[I7->sp_offset_in_saved_window()] + pc_return_offset;
// We must always be able to find a recognizable pc
CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
if (sender_pc == NULL || sender_blob == NULL) {
return false;
}
// It should be safe to construct the sender though it might not be valid
frame sender(_SENDER_SP, younger_sp, adjusted_stack);
// Do we have a valid fp?
address sender_fp = (address) sender.fp();
// an fp must be within the stack and above (but not equal) current frame's _FP
bool sender_fp_safe = (sender_fp <= thread->stack_base()) &&
(sender_fp > _FP);
if (!sender_fp_safe) {
return false;
}
// If the potential sender is the interpreter then we can do some more checking
if (Interpreter::contains(sender_pc)) {
return sender.is_interpreted_frame_valid(thread);
}
// Could just be some random pointer within the codeBlob
if (!sender.cb()->code_contains(sender_pc)) {
return false;
}
// We should never be able to see an adapter if the current frame is something from code cache
if (sender_blob->is_adapter_blob()) {
return false;
}
if( sender.is_entry_frame()) {
// Validate the JavaCallWrapper an entry frame must have
address jcw = (address)sender.entry_frame_call_wrapper();
bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > sender_fp);
return jcw_safe;
}
// If the frame size is 0 something is bad because every nmethod has a non-zero frame size
// because you must allocate window space
if (sender_blob->frame_size() == 0) {
assert(!sender_blob->is_nmethod(), "should count return address at least");
return false;
}
// The sender should positively be an nmethod or call_stub. On sparc we might in fact see something else.
// The cause of this is because at a save instruction the O7 we get is a leftover from an earlier
// window use. So if a runtime stub creates two frames (common in fastdebug/jvmg) then we see the
// stale pc. So if the sender blob is not something we'd expect we have little choice but to declare
// the stack unwalkable. pd_get_top_frame_for_signal_handler tries to recover from this by unwinding
// that initial frame and retrying.
if (!sender_blob->is_nmethod()) {
return false;
}
// Could put some more validation for the potential non-interpreted sender
// frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
// One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
// We've validated the potential sender that would be created
return true;
}
// Must be native-compiled frame. Since sender will try and use fp to find
// linkages it must be safe
if (!fp_safe) return false;
// could try and do some more potential verification of native frame if we could think of some...
return true;
}
inline bool frame::is_first_frame() const { return is_entry_frame() && entry_frame_is_first(); }
bool frame::is_first_frame() const {
return is_entry_frame() && !has_next_Delta_fp();
}
IC_Iterator* frame::sender_ic_iterator() const {
return is_entry_frame() ? NULL : sender().current_ic_iterator();
}
// Tells whether this is a Java frame.
bool is_java_frame( void ) const { return !is_entry_frame(); }
