451 inline frame freeze_start_frame_yield_stub();
452 template<typename FKind>
453 inline freeze_result recurse_freeze_java_frame(const frame& f, frame& caller, int fsize, int argsize);
454 inline void before_freeze_java_frame(const frame& f, const frame& caller, int fsize, int argsize, bool is_bottom_frame);
455 inline void after_freeze_java_frame(const frame& hf, bool is_bottom_frame);
456 freeze_result finalize_freeze(const frame& callee, frame& caller, int argsize);
457 void patch(const frame& f, frame& hf, const frame& caller, bool is_bottom_frame);
458 NOINLINE freeze_result recurse_freeze_interpreted_frame(frame& f, frame& caller, int callee_argsize, bool callee_interpreted);
459 freeze_result recurse_freeze_compiled_frame(frame& f, frame& caller, int callee_argsize, bool callee_interpreted);
460 NOINLINE freeze_result recurse_freeze_stub_frame(frame& f, frame& caller);
461 NOINLINE freeze_result recurse_freeze_native_frame(frame& f, frame& caller);
462 NOINLINE void finish_freeze(const frame& f, const frame& top);
463
464 void freeze_lockstack(stackChunkOop chunk);
465
466 inline bool stack_overflow();
467
468 static frame sender(const frame& f) { return f.is_interpreted_frame() ? sender<ContinuationHelper::InterpretedFrame>(f)
469 : sender<ContinuationHelper::NonInterpretedUnknownFrame>(f); }
470 template<typename FKind> static inline frame sender(const frame& f);
471 template<typename FKind> frame new_heap_frame(frame& f, frame& caller);
472 inline void set_top_frame_metadata_pd(const frame& hf);
473 inline void patch_pd(frame& callee, const frame& caller);
474 inline void patch_pd_unused(intptr_t* sp);
475 void adjust_interpreted_frame_unextended_sp(frame& f);
476 inline void prepare_freeze_interpreted_top_frame(frame& f);
477 static inline void relativize_interpreted_frame_metadata(const frame& f, const frame& hf);
478
479 protected:
480 void freeze_fast_copy(stackChunkOop chunk, int chunk_start_sp CONT_JFR_ONLY(COMMA bool chunk_is_allocated));
481 bool freeze_fast_new_chunk(stackChunkOop chunk);
482 };
483
484 template <typename ConfigT>
485 class Freeze : public FreezeBase {
486 private:
487 stackChunkOop allocate_chunk(size_t stack_size, int argsize_md);
488
489 public:
490 inline Freeze(JavaThread* thread, ContinuationWrapper& cont, intptr_t* frame_sp, bool preempt)
491 : FreezeBase(thread, cont, frame_sp, preempt) {}
492
493 freeze_result try_freeze_fast();
1163
1164 assert((!empty && Continuation::is_return_barrier_entry(entry.pc())) || (empty && Continuation::is_continuation_enterSpecial(entry)), "");
1165 assert(callee.is_interpreted_frame() || entry.sp() == entry.unextended_sp(), "");
1166 #endif
1167
1168 return freeze_ok_bottom;
1169 }
1170
1171 // After freezing a frame we need to possibly adjust some values related to the caller frame.
1172 void FreezeBase::patch(const frame& f, frame& hf, const frame& caller, bool is_bottom_frame) {
1173 if (is_bottom_frame) {
1174 // If we're the bottom frame, we need to replace the return barrier with the real
1175 // caller's pc.
1176 address last_pc = caller.pc();
1177 assert((last_pc == nullptr) == _cont.tail()->is_empty(), "");
1178 ContinuationHelper::Frame::patch_pc(caller, last_pc);
1179 } else {
1180 assert(!caller.is_empty(), "");
1181 }
1182
1183 patch_pd(hf, caller);
1184
1185 if (f.is_interpreted_frame()) {
1186 assert(hf.is_heap_frame(), "should be");
1187 ContinuationHelper::InterpretedFrame::patch_sender_sp(hf, caller);
1188 }
1189
1190 #ifdef ASSERT
1191 if (hf.is_compiled_frame()) {
1192 if (f.is_deoptimized_frame()) { // TODO DEOPT: long term solution: unroll on freeze and patch pc
1193 log_develop_trace(continuations)("Freezing deoptimized frame");
1194 assert(f.cb()->as_nmethod()->is_deopt_pc(f.raw_pc()), "");
1195 assert(f.cb()->as_nmethod()->is_deopt_pc(ContinuationHelper::Frame::real_pc(f)), "");
1196 }
1197 }
1198 #endif
1199 }
1200
1201 #ifdef ASSERT
1202 static void verify_frame_top(const frame& f, intptr_t* top) {
1203 ResourceMark rm;
1260
1261 CONT_JFR_ONLY(_jfr_info.record_interpreted_frame();)
1262 DEBUG_ONLY(after_freeze_java_frame(hf, is_bottom_frame);)
1263 caller = hf;
1264
1265 // Mark frame_method's GC epoch for class redefinition on_stack calculation.
1266 frame_method->record_gc_epoch();
1267
1268 return freeze_ok;
1269 }
1270
1271 // The parameter callee_argsize includes metadata that has to be part of caller/callee overlap.
1272 // See also StackChunkFrameStream<frame_kind>::frame_size()
1273 freeze_result FreezeBase::recurse_freeze_compiled_frame(frame& f, frame& caller,
1274 int callee_argsize /* incl. metadata */,
1275 bool callee_interpreted) {
1276 // The frame's top never includes the stack arguments to the callee
1277 intptr_t* const stack_frame_top = ContinuationHelper::CompiledFrame::frame_top(f, callee_argsize, callee_interpreted);
1278 intptr_t* const stack_frame_bottom = ContinuationHelper::CompiledFrame::frame_bottom(f);
1279 // including metadata between f and its stackargs
1280 const int argsize = ContinuationHelper::CompiledFrame::stack_argsize(f) + frame::metadata_words_at_top;
1281 const int fsize = pointer_delta_as_int(stack_frame_bottom + argsize, stack_frame_top);
1282
1283 log_develop_trace(continuations)("recurse_freeze_compiled_frame %s _size: %d fsize: %d argsize: %d",
1284 ContinuationHelper::Frame::frame_method(f) != nullptr ?
1285 ContinuationHelper::Frame::frame_method(f)->name_and_sig_as_C_string() : "",
1286 _freeze_size, fsize, argsize);
1287 // we'd rather not yield inside methods annotated with @JvmtiMountTransition
1288 assert(!ContinuationHelper::Frame::frame_method(f)->jvmti_mount_transition(), "");
1289
1290 freeze_result result = recurse_freeze_java_frame<ContinuationHelper::CompiledFrame>(f, caller, fsize, argsize);
1291 if (UNLIKELY(result > freeze_ok_bottom)) {
1292 return result;
1293 }
1294
1295 bool is_bottom_frame = result == freeze_ok_bottom;
1296 assert(!caller.is_empty() || is_bottom_frame, "");
1297
1298 DEBUG_ONLY(before_freeze_java_frame(f, caller, fsize, argsize, is_bottom_frame);)
1299
1300 frame hf = new_heap_frame<ContinuationHelper::CompiledFrame>(f, caller);
1301
1302 intptr_t* heap_frame_top = ContinuationHelper::CompiledFrame::frame_top(hf, callee_argsize, callee_interpreted);
1303
1304 copy_to_chunk(stack_frame_top, heap_frame_top, fsize);
1305 assert(!is_bottom_frame || !caller.is_compiled_frame() || (heap_frame_top + fsize) == (caller.unextended_sp() + argsize), "");
1306
1307 if (caller.is_interpreted_frame()) {
1308 // When thawing the frame we might need to add alignment (see Thaw::align)
1309 _total_align_size += frame::align_wiggle;
1310 }
1311
1312 patch(f, hf, caller, is_bottom_frame);
1313
1314 assert(is_bottom_frame || Interpreter::contains(ContinuationHelper::CompiledFrame::real_pc(caller)) == caller.is_interpreted_frame(), "");
1315
1316 DEBUG_ONLY(after_freeze_java_frame(hf, is_bottom_frame);)
1317 caller = hf;
1318 return freeze_ok;
1319 }
1320
2062
2063 // Only used for preemption on ObjectLocker
2064 ObjectMonitor* _init_lock;
2065
2066 StackChunkFrameStream<ChunkFrames::Mixed> _stream;
2067
2068 NOT_PRODUCT(int _frames;)
2069
2070 protected:
2071 ThawBase(JavaThread* thread, ContinuationWrapper& cont) :
2072 _thread(thread), _cont(cont),
2073 _fastpath(nullptr) {
2074 DEBUG_ONLY(_top_unextended_sp_before_thaw = nullptr;)
2075 assert (cont.tail() != nullptr, "no last chunk");
2076 DEBUG_ONLY(_top_stack_address = _cont.entrySP() - thaw_size(cont.tail());)
2077 }
2078
2079 void clear_chunk(stackChunkOop chunk);
2080 template<bool check_stub>
2081 int remove_top_compiled_frame_from_chunk(stackChunkOop chunk, int &argsize);
2082 void copy_from_chunk(intptr_t* from, intptr_t* to, int size);
2083
2084 void thaw_lockstack(stackChunkOop chunk);
2085
2086 // fast path
2087 inline void prefetch_chunk_pd(void* start, int size_words);
2088 void patch_return(intptr_t* sp, bool is_last);
2089
2090 intptr_t* handle_preempted_continuation(intptr_t* sp, Continuation::preempt_kind preempt_kind, bool fast_case);
2091 inline intptr_t* push_cleanup_continuation();
2092 inline intptr_t* push_preempt_adapter();
2093 intptr_t* redo_vmcall(JavaThread* current, frame& top);
2094 void throw_interrupted_exception(JavaThread* current, frame& top);
2095
2096 void recurse_thaw(const frame& heap_frame, frame& caller, int num_frames, bool top_on_preempt_case);
2097 void finish_thaw(frame& f);
2098
2099 private:
2100 template<typename FKind> bool recurse_thaw_java_frame(frame& caller, int num_frames);
2101 void finalize_thaw(frame& entry, int argsize);
2102
2103 inline bool seen_by_gc();
2104
2105 inline void before_thaw_java_frame(const frame& hf, const frame& caller, bool bottom, int num_frame);
2106 inline void after_thaw_java_frame(const frame& f, bool bottom);
2107 inline void patch(frame& f, const frame& caller, bool bottom);
2108 void clear_bitmap_bits(address start, address end);
2109
2110 NOINLINE void recurse_thaw_interpreted_frame(const frame& hf, frame& caller, int num_frames, bool is_top);
2111 void recurse_thaw_compiled_frame(const frame& hf, frame& caller, int num_frames, bool stub_caller);
2112 void recurse_thaw_stub_frame(const frame& hf, frame& caller, int num_frames);
2113 void recurse_thaw_native_frame(const frame& hf, frame& caller, int num_frames);
2114
2115 void push_return_frame(const frame& f);
2116 inline frame new_entry_frame();
2117 template<typename FKind> frame new_stack_frame(const frame& hf, frame& caller, bool bottom);
2118 inline void patch_pd(frame& f, const frame& sender);
2119 inline void patch_pd(frame& f, intptr_t* caller_sp);
2120 inline intptr_t* align(const frame& hf, intptr_t* frame_sp, frame& caller, bool bottom);
2121
2122 void maybe_set_fastpath(intptr_t* sp) { if (sp > _fastpath) _fastpath = sp; }
2123
2124 static inline void derelativize_interpreted_frame_metadata(const frame& hf, const frame& f);
2125
2126 public:
2127 CONT_JFR_ONLY(FreezeThawJfrInfo& jfr_info() { return _jfr_info; })
2128 };
2129
2130 template <typename ConfigT>
2131 class Thaw : public ThawBase {
2132 public:
2133 Thaw(JavaThread* thread, ContinuationWrapper& cont) : ThawBase(thread, cont) {}
2134
2135 inline bool can_thaw_fast(stackChunkOop chunk) {
2136 return !_barriers
2137 && _thread->cont_fastpath_thread_state()
2174 assert(_base - 1 <= top() + total_size() + frame::metadata_words_at_bottom, "missed entry frame");
2175 }
2176
2177 int entry_frame_extension() const { return _argsize + (_argsize > 0 ? frame::metadata_words_at_top : 0); }
2178
2179 // top and bottom stack pointers
2180 intptr_t* sp() const { return ContinuationHelper::frame_align_pointer(_base - _thaw_size); }
2181 intptr_t* bottom_sp() const { return ContinuationHelper::frame_align_pointer(_base - entry_frame_extension()); }
2182
2183 // several operations operate on the totality of the stack being reconstructed,
2184 // including the metadata words
2185 intptr_t* top() const { return sp() - frame::metadata_words_at_bottom; }
2186 int total_size() const { return _thaw_size + frame::metadata_words_at_bottom; }
2187 };
2188
2189 inline void ThawBase::clear_chunk(stackChunkOop chunk) {
2190 chunk->set_sp(chunk->bottom());
2191 chunk->set_max_thawing_size(0);
2192 }
2193
2194 template<bool check_stub>
2195 int ThawBase::remove_top_compiled_frame_from_chunk(stackChunkOop chunk, int &argsize) {
2196 bool empty = false;
2197 StackChunkFrameStream<ChunkFrames::CompiledOnly> f(chunk);
2198 DEBUG_ONLY(intptr_t* const chunk_sp = chunk->start_address() + chunk->sp();)
2199 assert(chunk_sp == f.sp(), "");
2200 assert(chunk_sp == f.unextended_sp(), "");
2201
2202 int frame_size = f.cb()->frame_size();
2203 argsize = f.stack_argsize();
2204
2205 assert(!f.is_stub() || check_stub, "");
2206 if (check_stub && f.is_stub()) {
2207 // If we don't thaw the top compiled frame too, after restoring the saved
2208 // registers back in Java, we would hit the return barrier to thaw one more
2209 // frame effectively overwriting the restored registers during that call.
2210 f.next(SmallRegisterMap::instance_no_args(), true /* stop */);
2211 assert(!f.is_done(), "");
2212
2213 f.get_cb();
2214 assert(f.is_compiled(), "");
2215 frame_size += f.cb()->frame_size();
2216 argsize = f.stack_argsize();
2217
2218 if (f.cb()->as_nmethod()->is_marked_for_deoptimization()) {
2219 // The caller of the runtime stub when the continuation is preempted is not at a
2220 // Java call instruction, and so cannot rely on nmethod patching for deopt.
2221 log_develop_trace(continuations)("Deoptimizing runtime stub caller");
2222 f.to_frame().deoptimize(nullptr); // the null thread simply avoids the assertion in deoptimize which we're not set up for
2223 }
2224 }
2225
2226 f.next(SmallRegisterMap::instance_no_args(), true /* stop */);
2227 empty = f.is_done();
2228 assert(!empty || argsize == chunk->argsize(), "");
2229
2230 if (empty) {
2231 clear_chunk(chunk);
2232 } else {
2233 chunk->set_sp(chunk->sp() + frame_size);
2234 chunk->set_max_thawing_size(chunk->max_thawing_size() - frame_size);
2235 // We set chunk->pc to the return pc into the next frame
2236 chunk->set_pc(f.pc());
2237 #ifdef ASSERT
2238 {
2239 intptr_t* retaddr_slot = (chunk_sp
2240 + frame_size
2241 - frame::sender_sp_ret_address_offset());
2242 assert(f.pc() == ContinuationHelper::return_address_at(retaddr_slot),
2243 "unexpected pc");
2504 assert(!_cont.is_empty(), "no more frames");
2505 assert(num_frames > 0, "");
2506 assert(!heap_frame.is_empty(), "");
2507
2508 if (top_on_preempt_case && (heap_frame.is_native_frame() || heap_frame.is_runtime_frame())) {
2509 heap_frame.is_native_frame() ? recurse_thaw_native_frame(heap_frame, caller, 2) : recurse_thaw_stub_frame(heap_frame, caller, 2);
2510 } else if (!heap_frame.is_interpreted_frame()) {
2511 recurse_thaw_compiled_frame(heap_frame, caller, num_frames, false);
2512 } else {
2513 recurse_thaw_interpreted_frame(heap_frame, caller, num_frames, top_on_preempt_case);
2514 }
2515 }
2516
2517 template<typename FKind>
2518 bool ThawBase::recurse_thaw_java_frame(frame& caller, int num_frames) {
2519 assert(num_frames > 0, "");
2520
2521 DEBUG_ONLY(_frames++;)
2522
2523 int argsize = _stream.stack_argsize();
2524
2525 _stream.next(SmallRegisterMap::instance_no_args());
2526 assert(_stream.to_frame().is_empty() == _stream.is_done(), "");
2527
2528 // we never leave a compiled caller of an interpreted frame as the top frame in the chunk
2529 // as it makes detecting that situation and adjusting unextended_sp tricky
2530 if (num_frames == 1 && !_stream.is_done() && FKind::interpreted && _stream.is_compiled()) {
2531 log_develop_trace(continuations)("thawing extra compiled frame to not leave a compiled interpreted-caller at top");
2532 num_frames++;
2533 }
2534
2535 if (num_frames == 1 || _stream.is_done()) { // end recursion
2536 finalize_thaw(caller, FKind::interpreted ? 0 : argsize);
2537 return true; // bottom
2538 } else { // recurse
2539 recurse_thaw(_stream.to_frame(), caller, num_frames - 1, false /* top_on_preempt_case */);
2540 return false;
2541 }
2542 }
2543
2544 void ThawBase::finalize_thaw(frame& entry, int argsize) {
2545 stackChunkOop chunk = _cont.tail();
2546
2547 if (!_stream.is_done()) {
2548 assert(_stream.sp() >= chunk->sp_address(), "");
2549 chunk->set_sp(chunk->to_offset(_stream.sp()));
2550 chunk->set_pc(_stream.pc());
2577 }
2578 assert(bottom == _cont.is_entry_frame(caller), "bottom: %d is_entry_frame: %d", bottom, _cont.is_entry_frame(hf));
2579 }
2580
2581 inline void ThawBase::after_thaw_java_frame(const frame& f, bool bottom) {
2582 #ifdef ASSERT
2583 LogTarget(Trace, continuations) lt;
2584 if (lt.develop_is_enabled()) {
2585 LogStream ls(lt);
2586 ls.print_cr("thawed frame:");
2587 print_frame_layout(f, false, &ls); // f.print_on(&ls);
2588 }
2589 #endif
2590 }
2591
2592 inline void ThawBase::patch(frame& f, const frame& caller, bool bottom) {
2593 assert(!bottom || caller.fp() == _cont.entryFP(), "");
2594 if (bottom) {
2595 ContinuationHelper::Frame::patch_pc(caller, _cont.is_empty() ? caller.pc()
2596 : StubRoutines::cont_returnBarrier());
2597 } else if (_should_patch_caller_pc) {
2598 // Caller was deoptimized during thaw but we've overwritten the return address when copying f from the heap.
2599 // Also, on some platforms, if the caller is interpreted but the callee not we also need to patch.
2600 assert(caller.is_deoptimized_frame() PPC64_ONLY(|| caller.is_interpreted_frame()), "");
2601 ContinuationHelper::Frame::patch_pc(caller, caller.raw_pc());
2602 _should_patch_caller_pc = false;
2603 }
2604
2605 patch_pd(f, caller);
2606
2607 if (f.is_interpreted_frame()) {
2608 ContinuationHelper::InterpretedFrame::patch_sender_sp(f, caller);
2609 }
2610
2611 assert(!bottom || !_cont.is_empty() || Continuation::is_continuation_entry_frame(f, nullptr), "");
2612 assert(!bottom || (_cont.is_empty() != Continuation::is_cont_barrier_frame(f)), "");
2613 assert(!caller.is_compiled_frame() || verify_deopt_state(caller), "");
2614 }
2615
2616 void ThawBase::clear_bitmap_bits(address start, address end) {
2617 assert(is_aligned(start, wordSize), "should be aligned: " PTR_FORMAT, p2i(start));
2618 assert(is_aligned(end, VMRegImpl::stack_slot_size), "should be aligned: " PTR_FORMAT, p2i(end));
2619
2620 // we need to clear the bits that correspond to arguments as they reside in the caller frame
2820 }
2821
2822 void ThawBase::recurse_thaw_compiled_frame(const frame& hf, frame& caller, int num_frames, bool stub_caller) {
2823 assert(hf.is_compiled_frame(), "");
2824 assert(_preempted_case || !stub_caller, "stub caller not at preemption");
2825
2826 if (!stub_caller && UNLIKELY(seen_by_gc())) { // recurse_thaw_stub_frame already invoked our barriers with a full regmap
2827 _cont.tail()->do_barriers<stackChunkOopDesc::BarrierType::Store>(_stream, SmallRegisterMap::instance_no_args());
2828 }
2829
2830 const bool is_bottom_frame = recurse_thaw_java_frame<ContinuationHelper::CompiledFrame>(caller, num_frames);
2831
2832 DEBUG_ONLY(before_thaw_java_frame(hf, caller, is_bottom_frame, num_frames);)
2833
2834 assert(caller.sp() == caller.unextended_sp(), "");
2835
2836 if ((!is_bottom_frame && caller.is_interpreted_frame()) || (is_bottom_frame && Interpreter::contains(_cont.tail()->pc()))) {
2837 _align_size += frame::align_wiggle; // we add one whether or not we've aligned because we add it in recurse_freeze_compiled_frame
2838 }
2839
2840 // new_stack_frame must construct the resulting frame using hf.pc() rather than hf.raw_pc() because the frame is not
2841 // yet laid out in the stack, and so the original_pc is not stored in it.
2842 // As a result, f.is_deoptimized_frame() is always false and we must test hf to know if the frame is deoptimized.
2843 frame f = new_stack_frame<ContinuationHelper::CompiledFrame>(hf, caller, is_bottom_frame);
2844 intptr_t* const stack_frame_top = f.sp();
2845 intptr_t* const heap_frame_top = hf.unextended_sp();
2846
2847 const int added_argsize = (is_bottom_frame || caller.is_interpreted_frame()) ? hf.compiled_frame_stack_argsize() : 0;
2848 int fsize = ContinuationHelper::CompiledFrame::size(hf) + added_argsize;
2849 assert(fsize <= (int)(caller.unextended_sp() - f.unextended_sp()), "");
2850
2851 intptr_t* from = heap_frame_top - frame::metadata_words_at_bottom;
2852 intptr_t* to = stack_frame_top - frame::metadata_words_at_bottom;
2853 // copy metadata, except the metadata at the top of the (unextended) entry frame
2854 int sz = fsize + frame::metadata_words_at_bottom + (is_bottom_frame && added_argsize == 0 ? 0 : frame::metadata_words_at_top);
2855
2856 // If we're the bottom-most thawed frame, we're writing to within one word from entrySP
2857 // (we might have one padding word for alignment)
2858 assert(!is_bottom_frame || (_cont.entrySP() - 1 <= to + sz && to + sz <= _cont.entrySP()), "");
2859 assert(!is_bottom_frame || hf.compiled_frame_stack_argsize() != 0 || (to + sz && to + sz == _cont.entrySP()), "");
2860
2861 copy_from_chunk(from, to, sz); // copying good oops because we invoked barriers above
2862
2863 patch(f, caller, is_bottom_frame);
2864
2865 // f.is_deoptimized_frame() is always false and we must test hf.is_deoptimized_frame() (see comment above)
2866 assert(!f.is_deoptimized_frame(), "");
2867 if (hf.is_deoptimized_frame()) {
2868 maybe_set_fastpath(f.sp());
2869 f.set_deoptimized();
2870 } else if (_thread->is_interp_only_mode()
|
451 inline frame freeze_start_frame_yield_stub();
452 template<typename FKind>
453 inline freeze_result recurse_freeze_java_frame(const frame& f, frame& caller, int fsize, int argsize);
454 inline void before_freeze_java_frame(const frame& f, const frame& caller, int fsize, int argsize, bool is_bottom_frame);
455 inline void after_freeze_java_frame(const frame& hf, bool is_bottom_frame);
456 freeze_result finalize_freeze(const frame& callee, frame& caller, int argsize);
457 void patch(const frame& f, frame& hf, const frame& caller, bool is_bottom_frame);
458 NOINLINE freeze_result recurse_freeze_interpreted_frame(frame& f, frame& caller, int callee_argsize, bool callee_interpreted);
459 freeze_result recurse_freeze_compiled_frame(frame& f, frame& caller, int callee_argsize, bool callee_interpreted);
460 NOINLINE freeze_result recurse_freeze_stub_frame(frame& f, frame& caller);
461 NOINLINE freeze_result recurse_freeze_native_frame(frame& f, frame& caller);
462 NOINLINE void finish_freeze(const frame& f, const frame& top);
463
464 void freeze_lockstack(stackChunkOop chunk);
465
466 inline bool stack_overflow();
467
468 static frame sender(const frame& f) { return f.is_interpreted_frame() ? sender<ContinuationHelper::InterpretedFrame>(f)
469 : sender<ContinuationHelper::NonInterpretedUnknownFrame>(f); }
470 template<typename FKind> static inline frame sender(const frame& f);
471 template<typename FKind> frame new_heap_frame(frame& f, frame& caller, int size_adjust = 0);
472 inline void set_top_frame_metadata_pd(const frame& hf);
473 inline void patch_pd(frame& callee, const frame& caller, bool is_bottom_frame);
474 inline void patch_pd_unused(intptr_t* sp);
475 void adjust_interpreted_frame_unextended_sp(frame& f);
476 inline void prepare_freeze_interpreted_top_frame(frame& f);
477 static inline void relativize_interpreted_frame_metadata(const frame& f, const frame& hf);
478
479 protected:
480 void freeze_fast_copy(stackChunkOop chunk, int chunk_start_sp CONT_JFR_ONLY(COMMA bool chunk_is_allocated));
481 bool freeze_fast_new_chunk(stackChunkOop chunk);
482 };
483
484 template <typename ConfigT>
485 class Freeze : public FreezeBase {
486 private:
487 stackChunkOop allocate_chunk(size_t stack_size, int argsize_md);
488
489 public:
490 inline Freeze(JavaThread* thread, ContinuationWrapper& cont, intptr_t* frame_sp, bool preempt)
491 : FreezeBase(thread, cont, frame_sp, preempt) {}
492
493 freeze_result try_freeze_fast();
1163
1164 assert((!empty && Continuation::is_return_barrier_entry(entry.pc())) || (empty && Continuation::is_continuation_enterSpecial(entry)), "");
1165 assert(callee.is_interpreted_frame() || entry.sp() == entry.unextended_sp(), "");
1166 #endif
1167
1168 return freeze_ok_bottom;
1169 }
1170
1171 // After freezing a frame we need to possibly adjust some values related to the caller frame.
1172 void FreezeBase::patch(const frame& f, frame& hf, const frame& caller, bool is_bottom_frame) {
1173 if (is_bottom_frame) {
1174 // If we're the bottom frame, we need to replace the return barrier with the real
1175 // caller's pc.
1176 address last_pc = caller.pc();
1177 assert((last_pc == nullptr) == _cont.tail()->is_empty(), "");
1178 ContinuationHelper::Frame::patch_pc(caller, last_pc);
1179 } else {
1180 assert(!caller.is_empty(), "");
1181 }
1182
1183 patch_pd(hf, caller, is_bottom_frame);
1184
1185 if (f.is_interpreted_frame()) {
1186 assert(hf.is_heap_frame(), "should be");
1187 ContinuationHelper::InterpretedFrame::patch_sender_sp(hf, caller);
1188 }
1189
1190 #ifdef ASSERT
1191 if (hf.is_compiled_frame()) {
1192 if (f.is_deoptimized_frame()) { // TODO DEOPT: long term solution: unroll on freeze and patch pc
1193 log_develop_trace(continuations)("Freezing deoptimized frame");
1194 assert(f.cb()->as_nmethod()->is_deopt_pc(f.raw_pc()), "");
1195 assert(f.cb()->as_nmethod()->is_deopt_pc(ContinuationHelper::Frame::real_pc(f)), "");
1196 }
1197 }
1198 #endif
1199 }
1200
1201 #ifdef ASSERT
1202 static void verify_frame_top(const frame& f, intptr_t* top) {
1203 ResourceMark rm;
1260
1261 CONT_JFR_ONLY(_jfr_info.record_interpreted_frame();)
1262 DEBUG_ONLY(after_freeze_java_frame(hf, is_bottom_frame);)
1263 caller = hf;
1264
1265 // Mark frame_method's GC epoch for class redefinition on_stack calculation.
1266 frame_method->record_gc_epoch();
1267
1268 return freeze_ok;
1269 }
1270
1271 // The parameter callee_argsize includes metadata that has to be part of caller/callee overlap.
1272 // See also StackChunkFrameStream<frame_kind>::frame_size()
1273 freeze_result FreezeBase::recurse_freeze_compiled_frame(frame& f, frame& caller,
1274 int callee_argsize /* incl. metadata */,
1275 bool callee_interpreted) {
1276 // The frame's top never includes the stack arguments to the callee
1277 intptr_t* const stack_frame_top = ContinuationHelper::CompiledFrame::frame_top(f, callee_argsize, callee_interpreted);
1278 intptr_t* const stack_frame_bottom = ContinuationHelper::CompiledFrame::frame_bottom(f);
1279 // including metadata between f and its stackargs
1280 int argsize = ContinuationHelper::CompiledFrame::stack_argsize(f) + frame::metadata_words_at_top;
1281 int fsize = pointer_delta_as_int(stack_frame_bottom + argsize, stack_frame_top);
1282
1283 int real_frame_size = 0;
1284 bool augmented = f.was_augmented_on_entry(real_frame_size);
1285 if (augmented) {
1286 // The args reside inside the frame so clear argsize. If the caller is compiled,
1287 // this will cause the stack arguments passed by the caller to be freezed when
1288 // freezing the caller frame itself. If the caller is interpreted this will have
1289 // the effect of discarding the arg area created in the i2c stub.
1290 argsize = 0;
1291 fsize = real_frame_size - (callee_interpreted ? 0 : callee_argsize);
1292 #ifdef ASSERT
1293 nmethod* nm = f.cb()->as_nmethod();
1294 Method* method = nm->method();
1295 address return_pc = ContinuationHelper::CompiledFrame::return_pc(f);
1296 CodeBlob* caller_cb = CodeCache::find_blob_fast(return_pc);
1297 assert(nm->is_compiled_by_c2() || (caller_cb->is_nmethod() && caller_cb->as_nmethod()->is_compiled_by_c2()), "caller or callee should be c2 compiled");
1298 assert((!caller_cb->is_nmethod() && nm->is_compiled_by_c2()) ||
1299 (nm->compiler_type() != caller_cb->as_nmethod()->compiler_type()) ||
1300 (nm->is_compiled_by_c2() && !method->is_static() && method->method_holder()->is_inline_klass()),
1301 "frame should not be extended");
1302 #endif
1303 }
1304
1305 log_develop_trace(continuations)("recurse_freeze_compiled_frame %s _size: %d fsize: %d argsize: %d augmented: %d",
1306 ContinuationHelper::Frame::frame_method(f) != nullptr ?
1307 ContinuationHelper::Frame::frame_method(f)->name_and_sig_as_C_string() : "",
1308 _freeze_size, fsize, argsize, augmented);
1309 // we'd rather not yield inside methods annotated with @JvmtiMountTransition
1310 assert(!ContinuationHelper::Frame::frame_method(f)->jvmti_mount_transition(), "");
1311
1312 freeze_result result = recurse_freeze_java_frame<ContinuationHelper::CompiledFrame>(f, caller, fsize, argsize);
1313 if (UNLIKELY(result > freeze_ok_bottom)) {
1314 return result;
1315 }
1316
1317 bool is_bottom_frame = result == freeze_ok_bottom;
1318 assert(!caller.is_empty() || is_bottom_frame, "");
1319 assert(!is_bottom_frame || !augmented, "thaw extended frame without caller?");
1320
1321 DEBUG_ONLY(before_freeze_java_frame(f, caller, fsize, argsize, is_bottom_frame);)
1322
1323 frame hf = new_heap_frame<ContinuationHelper::CompiledFrame>(f, caller, augmented ? real_frame_size - f.cb()->as_nmethod()->frame_size() : 0);
1324
1325 intptr_t* heap_frame_top = ContinuationHelper::CompiledFrame::frame_top(hf, callee_argsize, callee_interpreted);
1326
1327 copy_to_chunk(stack_frame_top, heap_frame_top, fsize);
1328 assert(!is_bottom_frame || !caller.is_compiled_frame() || (heap_frame_top + fsize) == (caller.unextended_sp() + argsize), "");
1329
1330 if (caller.is_interpreted_frame()) {
1331 // When thawing the frame we might need to add alignment (see Thaw::align)
1332 _total_align_size += frame::align_wiggle;
1333 }
1334
1335 patch(f, hf, caller, is_bottom_frame);
1336
1337 assert(is_bottom_frame || Interpreter::contains(ContinuationHelper::CompiledFrame::real_pc(caller)) == caller.is_interpreted_frame(), "");
1338
1339 DEBUG_ONLY(after_freeze_java_frame(hf, is_bottom_frame);)
1340 caller = hf;
1341 return freeze_ok;
1342 }
1343
2085
2086 // Only used for preemption on ObjectLocker
2087 ObjectMonitor* _init_lock;
2088
2089 StackChunkFrameStream<ChunkFrames::Mixed> _stream;
2090
2091 NOT_PRODUCT(int _frames;)
2092
2093 protected:
2094 ThawBase(JavaThread* thread, ContinuationWrapper& cont) :
2095 _thread(thread), _cont(cont),
2096 _fastpath(nullptr) {
2097 DEBUG_ONLY(_top_unextended_sp_before_thaw = nullptr;)
2098 assert (cont.tail() != nullptr, "no last chunk");
2099 DEBUG_ONLY(_top_stack_address = _cont.entrySP() - thaw_size(cont.tail());)
2100 }
2101
2102 void clear_chunk(stackChunkOop chunk);
2103 template<bool check_stub>
2104 int remove_top_compiled_frame_from_chunk(stackChunkOop chunk, int &argsize);
2105 int remove_scalarized_frames(StackChunkFrameStream<ChunkFrames::CompiledOnly>& scfs, int &argsize);
2106 void copy_from_chunk(intptr_t* from, intptr_t* to, int size);
2107
2108 void thaw_lockstack(stackChunkOop chunk);
2109
2110 // fast path
2111 inline void prefetch_chunk_pd(void* start, int size_words);
2112 void patch_return(intptr_t* sp, bool is_last);
2113
2114 intptr_t* handle_preempted_continuation(intptr_t* sp, Continuation::preempt_kind preempt_kind, bool fast_case);
2115 inline intptr_t* push_cleanup_continuation();
2116 inline intptr_t* push_preempt_adapter();
2117 intptr_t* redo_vmcall(JavaThread* current, frame& top);
2118 void throw_interrupted_exception(JavaThread* current, frame& top);
2119
2120 void recurse_thaw(const frame& heap_frame, frame& caller, int num_frames, bool top_on_preempt_case);
2121 void finish_thaw(frame& f);
2122
2123 private:
2124 template<typename FKind> bool recurse_thaw_java_frame(frame& caller, int num_frames);
2125 void finalize_thaw(frame& entry, int argsize);
2126
2127 inline bool seen_by_gc();
2128
2129 inline void before_thaw_java_frame(const frame& hf, const frame& caller, bool bottom, int num_frame);
2130 inline void after_thaw_java_frame(const frame& f, bool bottom);
2131 inline void patch(frame& f, const frame& caller, bool bottom);
2132 void clear_bitmap_bits(address start, address end);
2133
2134 NOINLINE void recurse_thaw_interpreted_frame(const frame& hf, frame& caller, int num_frames, bool is_top);
2135 void recurse_thaw_compiled_frame(const frame& hf, frame& caller, int num_frames, bool stub_caller);
2136 void recurse_thaw_stub_frame(const frame& hf, frame& caller, int num_frames);
2137 void recurse_thaw_native_frame(const frame& hf, frame& caller, int num_frames);
2138
2139 void push_return_frame(const frame& f);
2140 inline frame new_entry_frame();
2141 template<typename FKind> frame new_stack_frame(const frame& hf, frame& caller, bool bottom, int size_adjust = 0);
2142 inline void patch_pd(frame& f, const frame& sender);
2143 inline void patch_pd(frame& f, intptr_t* caller_sp);
2144 inline intptr_t* align(const frame& hf, intptr_t* frame_sp, frame& caller, bool bottom);
2145
2146 void maybe_set_fastpath(intptr_t* sp) { if (sp > _fastpath) _fastpath = sp; }
2147
2148 static inline void derelativize_interpreted_frame_metadata(const frame& hf, const frame& f);
2149
2150 public:
2151 CONT_JFR_ONLY(FreezeThawJfrInfo& jfr_info() { return _jfr_info; })
2152 };
2153
2154 template <typename ConfigT>
2155 class Thaw : public ThawBase {
2156 public:
2157 Thaw(JavaThread* thread, ContinuationWrapper& cont) : ThawBase(thread, cont) {}
2158
2159 inline bool can_thaw_fast(stackChunkOop chunk) {
2160 return !_barriers
2161 && _thread->cont_fastpath_thread_state()
2198 assert(_base - 1 <= top() + total_size() + frame::metadata_words_at_bottom, "missed entry frame");
2199 }
2200
2201 int entry_frame_extension() const { return _argsize + (_argsize > 0 ? frame::metadata_words_at_top : 0); }
2202
2203 // top and bottom stack pointers
2204 intptr_t* sp() const { return ContinuationHelper::frame_align_pointer(_base - _thaw_size); }
2205 intptr_t* bottom_sp() const { return ContinuationHelper::frame_align_pointer(_base - entry_frame_extension()); }
2206
2207 // several operations operate on the totality of the stack being reconstructed,
2208 // including the metadata words
2209 intptr_t* top() const { return sp() - frame::metadata_words_at_bottom; }
2210 int total_size() const { return _thaw_size + frame::metadata_words_at_bottom; }
2211 };
2212
2213 inline void ThawBase::clear_chunk(stackChunkOop chunk) {
2214 chunk->set_sp(chunk->bottom());
2215 chunk->set_max_thawing_size(0);
2216 }
2217
2218 int ThawBase::remove_scalarized_frames(StackChunkFrameStream<ChunkFrames::CompiledOnly>& f, int &argsize) {
2219 intptr_t* top = f.sp();
2220
2221 while (f.cb()->as_nmethod()->needs_stack_repair()) {
2222 f.next(SmallRegisterMap::instance_no_args(), false /* stop */);
2223 }
2224 assert(!f.is_done(), "");
2225 assert(f.is_compiled(), "");
2226
2227 intptr_t* bottom = f.sp() + f.cb()->frame_size();
2228 argsize = f.stack_argsize();
2229 return bottom - top;
2230 }
2231
2232 template<bool check_stub>
2233 int ThawBase::remove_top_compiled_frame_from_chunk(stackChunkOop chunk, int &argsize) {
2234 bool empty = false;
2235 StackChunkFrameStream<ChunkFrames::CompiledOnly> f(chunk);
2236 DEBUG_ONLY(intptr_t* const chunk_sp = chunk->start_address() + chunk->sp();)
2237 assert(chunk_sp == f.sp(), "");
2238 assert(chunk_sp == f.unextended_sp(), "");
2239
2240 int frame_size = f.cb()->frame_size();
2241 argsize = f.stack_argsize();
2242
2243 assert(!f.is_stub() || check_stub, "");
2244 if (check_stub && f.is_stub()) {
2245 // If we don't thaw the top compiled frame too, after restoring the saved
2246 // registers back in Java, we would hit the return barrier to thaw one more
2247 // frame effectively overwriting the restored registers during that call.
2248 f.next(SmallRegisterMap::instance_no_args(), true /* stop */);
2249 assert(!f.is_done(), "");
2250
2251 f.get_cb();
2252 assert(f.is_compiled(), "");
2253
2254 if (f.cb()->as_nmethod()->is_marked_for_deoptimization()) {
2255 // The caller of the runtime stub when the continuation is preempted is not at a
2256 // Java call instruction, and so cannot rely on nmethod patching for deopt.
2257 log_develop_trace(continuations)("Deoptimizing runtime stub caller");
2258 f.to_frame().deoptimize(nullptr); // the null thread simply avoids the assertion in deoptimize which we're not set up for
2259 }
2260
2261 if (f.cb()->as_nmethod()->needs_stack_repair()) {
2262 frame_size += remove_scalarized_frames(f, argsize);
2263 } else {
2264 frame_size += f.cb()->frame_size();
2265 argsize = f.stack_argsize();
2266 }
2267 } else if (f.cb()->as_nmethod()->needs_stack_repair()) {
2268 frame_size = remove_scalarized_frames(f, argsize);
2269 }
2270
2271 f.next(SmallRegisterMap::instance_no_args(), true /* stop */);
2272 empty = f.is_done();
2273 assert(!empty || argsize == chunk->argsize(), "");
2274
2275 if (empty) {
2276 clear_chunk(chunk);
2277 } else {
2278 chunk->set_sp(chunk->sp() + frame_size);
2279 chunk->set_max_thawing_size(chunk->max_thawing_size() - frame_size);
2280 // We set chunk->pc to the return pc into the next frame
2281 chunk->set_pc(f.pc());
2282 #ifdef ASSERT
2283 {
2284 intptr_t* retaddr_slot = (chunk_sp
2285 + frame_size
2286 - frame::sender_sp_ret_address_offset());
2287 assert(f.pc() == ContinuationHelper::return_address_at(retaddr_slot),
2288 "unexpected pc");
2549 assert(!_cont.is_empty(), "no more frames");
2550 assert(num_frames > 0, "");
2551 assert(!heap_frame.is_empty(), "");
2552
2553 if (top_on_preempt_case && (heap_frame.is_native_frame() || heap_frame.is_runtime_frame())) {
2554 heap_frame.is_native_frame() ? recurse_thaw_native_frame(heap_frame, caller, 2) : recurse_thaw_stub_frame(heap_frame, caller, 2);
2555 } else if (!heap_frame.is_interpreted_frame()) {
2556 recurse_thaw_compiled_frame(heap_frame, caller, num_frames, false);
2557 } else {
2558 recurse_thaw_interpreted_frame(heap_frame, caller, num_frames, top_on_preempt_case);
2559 }
2560 }
2561
2562 template<typename FKind>
2563 bool ThawBase::recurse_thaw_java_frame(frame& caller, int num_frames) {
2564 assert(num_frames > 0, "");
2565
2566 DEBUG_ONLY(_frames++;)
2567
2568 int argsize = _stream.stack_argsize();
2569 CodeBlob* cb = _stream.cb();
2570
2571 _stream.next(SmallRegisterMap::instance_no_args());
2572 assert(_stream.to_frame().is_empty() == _stream.is_done(), "");
2573
2574 // We never leave a compiled caller of an interpreted frame as the top frame in the chunk
2575 // as it makes detecting that situation and adjusting unextended_sp tricky. We also always
2576 // thaw the caller of a frame that needs_stack_repair, as it would otherwise complicate things:
2577 // - Regardless of whether the frame was extended or not, we would need to copy the right arg
2578 // size if its greater than the one given by the normal method signature (non-scalarized).
2579 // - If the frame was indeed extended, leaving its caller as the top frame would complicate walking
2580 // the chunk (we need unextended_sp, but we only have sp).
2581 if (num_frames == 1 && !_stream.is_done() && ((FKind::interpreted && _stream.is_compiled()) || (FKind::compiled && cb->as_nmethod_or_null()->needs_stack_repair()))) {
2582 log_develop_trace(continuations)("thawing extra compiled frame to not leave a compiled interpreted-caller at top");
2583 num_frames++;
2584 }
2585
2586 if (num_frames == 1 || _stream.is_done()) { // end recursion
2587 finalize_thaw(caller, FKind::interpreted ? 0 : argsize);
2588 return true; // bottom
2589 } else { // recurse
2590 recurse_thaw(_stream.to_frame(), caller, num_frames - 1, false /* top_on_preempt_case */);
2591 return false;
2592 }
2593 }
2594
2595 void ThawBase::finalize_thaw(frame& entry, int argsize) {
2596 stackChunkOop chunk = _cont.tail();
2597
2598 if (!_stream.is_done()) {
2599 assert(_stream.sp() >= chunk->sp_address(), "");
2600 chunk->set_sp(chunk->to_offset(_stream.sp()));
2601 chunk->set_pc(_stream.pc());
2628 }
2629 assert(bottom == _cont.is_entry_frame(caller), "bottom: %d is_entry_frame: %d", bottom, _cont.is_entry_frame(hf));
2630 }
2631
2632 inline void ThawBase::after_thaw_java_frame(const frame& f, bool bottom) {
2633 #ifdef ASSERT
2634 LogTarget(Trace, continuations) lt;
2635 if (lt.develop_is_enabled()) {
2636 LogStream ls(lt);
2637 ls.print_cr("thawed frame:");
2638 print_frame_layout(f, false, &ls); // f.print_on(&ls);
2639 }
2640 #endif
2641 }
2642
2643 inline void ThawBase::patch(frame& f, const frame& caller, bool bottom) {
2644 assert(!bottom || caller.fp() == _cont.entryFP(), "");
2645 if (bottom) {
2646 ContinuationHelper::Frame::patch_pc(caller, _cont.is_empty() ? caller.pc()
2647 : StubRoutines::cont_returnBarrier());
2648 } else if (_should_patch_caller_pc || caller.is_compiled_frame()) {
2649 // Caller was deoptimized during thaw but we've overwritten the return address when copying f from the heap.
2650 // Also, on some platforms, if the caller is interpreted but the callee not we also need to patch.
2651 assert(!_should_patch_caller_pc || caller.is_deoptimized_frame() PPC64_ONLY(|| caller.is_interpreted_frame()), "");
2652 ContinuationHelper::Frame::patch_pc(caller, caller.raw_pc());
2653 _should_patch_caller_pc = false;
2654 }
2655
2656 patch_pd(f, caller);
2657
2658 if (f.is_interpreted_frame()) {
2659 ContinuationHelper::InterpretedFrame::patch_sender_sp(f, caller);
2660 }
2661
2662 assert(!bottom || !_cont.is_empty() || Continuation::is_continuation_entry_frame(f, nullptr), "");
2663 assert(!bottom || (_cont.is_empty() != Continuation::is_cont_barrier_frame(f)), "");
2664 assert(!caller.is_compiled_frame() || verify_deopt_state(caller), "");
2665 }
2666
2667 void ThawBase::clear_bitmap_bits(address start, address end) {
2668 assert(is_aligned(start, wordSize), "should be aligned: " PTR_FORMAT, p2i(start));
2669 assert(is_aligned(end, VMRegImpl::stack_slot_size), "should be aligned: " PTR_FORMAT, p2i(end));
2670
2671 // we need to clear the bits that correspond to arguments as they reside in the caller frame
2871 }
2872
2873 void ThawBase::recurse_thaw_compiled_frame(const frame& hf, frame& caller, int num_frames, bool stub_caller) {
2874 assert(hf.is_compiled_frame(), "");
2875 assert(_preempted_case || !stub_caller, "stub caller not at preemption");
2876
2877 if (!stub_caller && UNLIKELY(seen_by_gc())) { // recurse_thaw_stub_frame already invoked our barriers with a full regmap
2878 _cont.tail()->do_barriers<stackChunkOopDesc::BarrierType::Store>(_stream, SmallRegisterMap::instance_no_args());
2879 }
2880
2881 const bool is_bottom_frame = recurse_thaw_java_frame<ContinuationHelper::CompiledFrame>(caller, num_frames);
2882
2883 DEBUG_ONLY(before_thaw_java_frame(hf, caller, is_bottom_frame, num_frames);)
2884
2885 assert(caller.sp() == caller.unextended_sp(), "");
2886
2887 if ((!is_bottom_frame && caller.is_interpreted_frame()) || (is_bottom_frame && Interpreter::contains(_cont.tail()->pc()))) {
2888 _align_size += frame::align_wiggle; // we add one whether or not we've aligned because we add it in recurse_freeze_compiled_frame
2889 }
2890
2891 int fsize = 0;
2892 int added_argsize = 0;
2893 bool augmented = hf.was_augmented_on_entry(fsize);
2894 if (!augmented) {
2895 added_argsize = (is_bottom_frame || caller.is_interpreted_frame()) ? hf.compiled_frame_stack_argsize() : 0;
2896 fsize += added_argsize;
2897 }
2898 assert(!is_bottom_frame || !augmented, "");
2899
2900 // new_stack_frame must construct the resulting frame using hf.pc() rather than hf.raw_pc() because the frame is not
2901 // yet laid out in the stack, and so the original_pc is not stored in it.
2902 // As a result, f.is_deoptimized_frame() is always false and we must test hf to know if the frame is deoptimized.
2903 frame f = new_stack_frame<ContinuationHelper::CompiledFrame>(hf, caller, is_bottom_frame, augmented ? fsize - hf.cb()->frame_size() : 0);
2904 assert((int)(caller.sp() - f.sp()) == (augmented ? fsize : f.cb()->frame_size()), "");
2905
2906 intptr_t* const stack_frame_top = f.sp();
2907 intptr_t* const heap_frame_top = hf.unextended_sp();
2908 intptr_t* from = heap_frame_top - frame::metadata_words_at_bottom;
2909 intptr_t* to = stack_frame_top - frame::metadata_words_at_bottom;
2910 // copy metadata, except the metadata at the top of the (unextended) entry frame
2911 int sz = fsize + frame::metadata_words_at_bottom + (is_bottom_frame && added_argsize == 0 ? 0 : frame::metadata_words_at_top);
2912
2913 // If we're the bottom-most thawed frame, we're writing to within one word from entrySP
2914 // (we might have one padding word for alignment)
2915 assert(!is_bottom_frame || (_cont.entrySP() - 1 <= to + sz && to + sz <= _cont.entrySP()), "");
2916 assert(!is_bottom_frame || hf.compiled_frame_stack_argsize() != 0 || (to + sz && to + sz == _cont.entrySP()), "");
2917
2918 copy_from_chunk(from, to, sz); // copying good oops because we invoked barriers above
2919
2920 patch(f, caller, is_bottom_frame);
2921
2922 // f.is_deoptimized_frame() is always false and we must test hf.is_deoptimized_frame() (see comment above)
2923 assert(!f.is_deoptimized_frame(), "");
2924 if (hf.is_deoptimized_frame()) {
2925 maybe_set_fastpath(f.sp());
2926 f.set_deoptimized();
2927 } else if (_thread->is_interp_only_mode()
|