1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
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  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
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 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 24 
 25 #ifndef CPU_AARCH64_CONTINUATIONFREEZETHAW_AARCH64_INLINE_HPP
 26 #define CPU_AARCH64_CONTINUATIONFREEZETHAW_AARCH64_INLINE_HPP
 27 
 28 #include "code/codeBlob.inline.hpp"
 29 #include "oops/stackChunkOop.inline.hpp"
 30 #include "runtime/frame.hpp"
 31 #include "runtime/frame.inline.hpp"
 32 
 33 
 34 inline void patch_callee_link(const frame& f, intptr_t* fp) {
 35   DEBUG_ONLY(intptr_t* orig = *ContinuationHelper::Frame::callee_link_address(f));
 36   *ContinuationHelper::Frame::callee_link_address(f) = fp;
 37 }
 38 
 39 inline void patch_callee_link_relative(const frame& f, intptr_t* fp) {
 40   intptr_t* la = (intptr_t*)ContinuationHelper::Frame::callee_link_address(f);
 41   intptr_t new_value = fp - la;
 42   *la = new_value;
 43 }
 44 
 45 ////// Freeze
 46 
 47 // Fast path
 48 
 49 inline void FreezeBase::patch_stack_pd(intptr_t* frame_sp, intptr_t* heap_sp) {
 50   // copy the spilled fp from the heap to the stack
 51   *(frame_sp - frame::sender_sp_offset) = *(heap_sp - frame::sender_sp_offset);
 52 }
 53 
 54 // Slow path
 55 
 56 template<typename FKind>
 57 inline frame FreezeBase::sender(const frame& f) {
 58   assert(FKind::is_instance(f), "");
 59   if (FKind::interpreted) {
 60     return frame(f.sender_sp(), f.interpreter_frame_sender_sp(), f.link(), f.sender_pc());
 61   }
 62   intptr_t** link_addr = link_address<FKind>(f);
 63 
 64   intptr_t* sender_sp = (intptr_t*)(link_addr + frame::sender_sp_offset); //  f.unextended_sp() + (fsize/wordSize); //
 65   address sender_pc = ContinuationHelper::return_address_at(sender_sp - 1);
 66   assert(sender_sp != f.sp(), "must have changed");
 67 
 68   int slot = 0;
 69   CodeBlob* sender_cb = CodeCache::find_blob_and_oopmap(sender_pc, slot);
 70   return sender_cb != nullptr
 71     ? frame(sender_sp, sender_sp, *link_addr, sender_pc, sender_cb,
 72             slot == -1 ? nullptr : sender_cb->oop_map_for_slot(slot, sender_pc),
 73             false /* on_heap ? */)
 74     : frame(sender_sp, sender_sp, *link_addr, sender_pc);
 75 }
 76 
 77 template<typename FKind>
 78 frame FreezeBase::new_heap_frame(frame& f, frame& caller) {
 79   assert(FKind::is_instance(f), "");
 80   assert(!caller.is_interpreted_frame()
 81     || caller.unextended_sp() == (intptr_t*)caller.at(frame::interpreter_frame_last_sp_offset), "");
 82 
 83   intptr_t *sp, *fp; // sp is really our unextended_sp
 84   if (FKind::interpreted) {
 85     assert((intptr_t*)f.at(frame::interpreter_frame_last_sp_offset) == nullptr
 86       || f.unextended_sp() == (intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset), "");
 87     intptr_t locals_offset = *f.addr_at(frame::interpreter_frame_locals_offset);
 88     // If the caller.is_empty(), i.e. we're freezing into an empty chunk, then we set
 89     // the chunk's argsize in finalize_freeze and make room for it above the unextended_sp
 90     bool overlap_caller = caller.is_interpreted_frame() || caller.is_empty();
 91     fp = caller.unextended_sp() - 1 - locals_offset + (overlap_caller ? ContinuationHelper::InterpretedFrame::stack_argsize(f) : 0);
 92     sp = fp - (f.fp() - f.unextended_sp());
 93     assert(sp <= fp, "");
 94     assert(fp <= caller.unextended_sp(), "");
 95     caller.set_sp(fp + frame::sender_sp_offset);
 96 
 97     assert(_cont.tail()->is_in_chunk(sp), "");
 98 
 99     frame hf(sp, sp, fp, f.pc(), nullptr, nullptr, true /* on_heap */);
100     // copy relativized locals from the stack frame
101     *hf.addr_at(frame::interpreter_frame_locals_offset) = locals_offset;
102     return hf;
103   } else {
104     // We need to re-read fp out of the frame because it may be an oop and we might have
105     // had a safepoint in finalize_freeze, after constructing f.
106     fp = *(intptr_t**)(f.sp() - frame::sender_sp_offset);
107 
108     int fsize = FKind::size(f);
109     sp = caller.unextended_sp() - fsize;
110     if (caller.is_interpreted_frame()) {
111       // If the caller is interpreted, our stackargs are not supposed to overlap with it
112       // so we make more room by moving sp down by argsize
113       int argsize = FKind::stack_argsize(f);
114       sp -= argsize;
115     }
116     caller.set_sp(sp + fsize);
117 
118     assert(_cont.tail()->is_in_chunk(sp), "");
119 
120     return frame(sp, sp, fp, f.pc(), nullptr, nullptr, true /* on_heap */);
121   }
122 }
123 
124 void FreezeBase::adjust_interpreted_frame_unextended_sp(frame& f) {
125   assert((f.at(frame::interpreter_frame_last_sp_offset) != 0) || (f.unextended_sp() == f.sp()), "");
126   intptr_t* real_unextended_sp = (intptr_t*)f.at_relative_or_null(frame::interpreter_frame_last_sp_offset);
127   if (real_unextended_sp != nullptr) {
128     f.set_unextended_sp(real_unextended_sp); // can be null at a safepoint
129   }
130 }
131 
132 inline void FreezeBase::prepare_freeze_interpreted_top_frame(frame& f) {
133   assert(f.interpreter_frame_last_sp() == nullptr, "should be null for top frame");
134   f.interpreter_frame_set_last_sp(f.unextended_sp());
135 }
136 
137 inline void FreezeBase::relativize_interpreted_frame_metadata(const frame& f, const frame& hf) {
138   assert(hf.fp() == hf.unextended_sp() + (f.fp() - f.unextended_sp()), "");
139   assert((f.at(frame::interpreter_frame_last_sp_offset) != 0)
140     || (f.unextended_sp() == f.sp()), "");
141   assert(f.fp() > (intptr_t*)f.at_relative(frame::interpreter_frame_initial_sp_offset), "");
142 
143   // on AARCH64, we may insert padding between the locals and the rest of the frame
144   // (see TemplateInterpreterGenerator::generate_normal_entry, and AbstractInterpreter::layout_activation)
145   // because we freeze the padding word (see recurse_freeze_interpreted_frame) in order to keep the same relativized
146   // locals value, we don't need to change the locals value here.
147 
148   // Make sure that last_sp is already relativized.
149   assert((intptr_t*)hf.at_relative(frame::interpreter_frame_last_sp_offset) == hf.unextended_sp(), "");
150 
151   // Make sure that monitor_block_top is already relativized.
152   assert(hf.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
153 
154   // extended_sp is already relativized by TemplateInterpreterGenerator::generate_normal_entry or
155   // AbstractInterpreter::layout_activation
156 
157   // The interpreter native wrapper code adds space in the stack equal to size_of_parameters()
158   // after the fixed part of the frame. For wait0 this is equal to 3 words (this + long parameter).
159   // We adjust by this size since otherwise the saved last sp will be less than the extended_sp.
160   DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
161   DEBUG_ONLY(int extra_space = m->is_object_wait0() ? m->size_of_parameters() : 0;)
162 
163   assert((hf.fp() - hf.unextended_sp()) == (f.fp() - f.unextended_sp()), "");
164   assert(hf.unextended_sp() == (intptr_t*)hf.at(frame::interpreter_frame_last_sp_offset), "");
165   assert(hf.unextended_sp() <= (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
166   assert(hf.unextended_sp() + extra_space >  (intptr_t*)hf.at(frame::interpreter_frame_extended_sp_offset), "");
167   assert(hf.fp()            >  (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
168   assert(hf.fp()            <= (intptr_t*)hf.at(frame::interpreter_frame_locals_offset), "");
169 }
170 
171 inline void FreezeBase::set_top_frame_metadata_pd(const frame& hf) {
172   stackChunkOop chunk = _cont.tail();
173   assert(chunk->is_in_chunk(hf.sp() - 1), "");
174   assert(chunk->is_in_chunk(hf.sp() - frame::sender_sp_offset), "");
175 
176   *(hf.sp() - 1) = (intptr_t)hf.pc();
177 
178   intptr_t* fp_addr = hf.sp() - frame::sender_sp_offset;
179   *fp_addr = hf.is_interpreted_frame() ? (intptr_t)(hf.fp() - fp_addr)
180                                        : (intptr_t)hf.fp();
181 }
182 
183 inline void FreezeBase::patch_pd(frame& hf, const frame& caller) {
184   if (caller.is_interpreted_frame()) {
185     assert(!caller.is_empty(), "");
186     patch_callee_link_relative(caller, caller.fp());
187   } else {
188     // If we're the bottom-most frame frozen in this freeze, the caller might have stayed frozen in the chunk,
189     // and its oop-containing fp fixed. We've now just overwritten it, so we must patch it back to its value
190     // as read from the chunk.
191     patch_callee_link(caller, caller.fp());
192   }
193 }
194 
195 inline intptr_t* AnchorMark::anchor_mark_set_pd() {
196   intptr_t* sp = _top_frame.sp();
197   if (_top_frame.is_interpreted_frame()) {
198     // In case the top frame is interpreted we need to set up the anchor using
199     // the last_sp saved in the frame (remove possible alignment added while
200     // thawing, see ThawBase::finish_thaw()). We also need to clear the last_sp
201     // saved in the frame as it is not expected to be set in case we preempt again.
202     _last_sp_from_frame = _top_frame.interpreter_frame_last_sp();
203     assert(_last_sp_from_frame != nullptr, "");
204     _top_frame.interpreter_frame_set_last_sp(nullptr);
205     if (sp != _last_sp_from_frame) {
206       _last_sp_from_frame[-1] = (intptr_t)_top_frame.pc();
207       _last_sp_from_frame[-2] = (intptr_t)_top_frame.fp();
208     }
209     _is_interpreted = true;
210     sp = _last_sp_from_frame;
211   }
212   return sp;
213 }
214 
215 inline void AnchorMark::anchor_mark_clear_pd() {
216   if (_is_interpreted) {
217     // Restore last_sp_from_frame and possibly overwritten pc.
218     _top_frame.interpreter_frame_set_last_sp(_last_sp_from_frame);
219     intptr_t* sp = _top_frame.sp();
220     if (sp != _last_sp_from_frame) {
221       sp[-1] = (intptr_t)_top_frame.pc();
222     }  
223   }
224 }
225 
226 //////// Thaw
227 
228 // Fast path
229 
230 inline void ThawBase::prefetch_chunk_pd(void* start, int size) {
231   size <<= LogBytesPerWord;
232   Prefetch::read(start, size);
233   Prefetch::read(start, size - 64);
234 }
235 
236 template <typename ConfigT>
237 inline void Thaw<ConfigT>::patch_caller_links(intptr_t* sp, intptr_t* bottom) {
238   // Fast path depends on !PreserveFramePointer. See can_thaw_fast().
239   assert(!PreserveFramePointer, "Frame pointers need to be fixed");
240 }
241 
242 // Slow path
243 
244 inline frame ThawBase::new_entry_frame() {
245   intptr_t* sp = _cont.entrySP();
246   return frame(sp, sp, _cont.entryFP(), _cont.entryPC()); // TODO PERF: This finds code blob and computes deopt state
247 }
248 
249 template<typename FKind> frame ThawBase::new_stack_frame(const frame& hf, frame& caller, bool bottom) {
250   assert(FKind::is_instance(hf), "");
251   // The values in the returned frame object will be written into the callee's stack in patch.
252 
253   if (FKind::interpreted) {
254     intptr_t* heap_sp = hf.unextended_sp();
255     // If caller is interpreted it already made room for the callee arguments
256     int overlap = caller.is_interpreted_frame() ? ContinuationHelper::InterpretedFrame::stack_argsize(hf) : 0;
257     const int fsize = (int)(ContinuationHelper::InterpretedFrame::frame_bottom(hf) - hf.unextended_sp() - overlap);
258     intptr_t* frame_sp = caller.unextended_sp() - fsize;
259     intptr_t* fp = frame_sp + (hf.fp() - heap_sp);
260     if ((intptr_t)fp % frame::frame_alignment != 0) {
261       fp--;
262       frame_sp--;
263       log_develop_trace(continuations)("Adding internal interpreted frame alignment");
264     }
265     DEBUG_ONLY(intptr_t* unextended_sp = fp + *hf.addr_at(frame::interpreter_frame_last_sp_offset);)
266     assert(frame_sp == unextended_sp, "");
267     caller.set_sp(fp + frame::sender_sp_offset);
268     frame f(frame_sp, frame_sp, fp, hf.pc());
269     // we need to set the locals so that the caller of new_stack_frame() can call
270     // ContinuationHelper::InterpretedFrame::frame_bottom
271     // copy relativized locals from the heap frame
272     *f.addr_at(frame::interpreter_frame_locals_offset) = *hf.addr_at(frame::interpreter_frame_locals_offset);
273     assert((intptr_t)f.fp() % frame::frame_alignment == 0, "");
274     return f;
275   } else {
276     int fsize = FKind::size(hf);
277     intptr_t* frame_sp = caller.unextended_sp() - fsize;
278     if (bottom || caller.is_interpreted_frame()) {
279       int argsize = FKind::stack_argsize(hf);
280 
281       fsize += argsize;
282       frame_sp   -= argsize;
283       caller.set_sp(caller.sp() - argsize);
284       assert(caller.sp() == frame_sp + (fsize-argsize), "");
285 
286       frame_sp = align(hf, frame_sp, caller, bottom);
287     }
288 
289     assert(hf.cb() != nullptr, "");
290     assert(hf.oop_map() != nullptr, "");
291     intptr_t* fp;
292     if (PreserveFramePointer) {
293       // we need to recreate a "real" frame pointer, pointing into the stack
294       fp = frame_sp + FKind::size(hf) - frame::sender_sp_offset;
295     } else {
296       fp = FKind::stub || FKind::native
297         ? frame_sp + fsize - frame::sender_sp_offset // fp always points to the address below the pushed return pc. We need correct address.
298         : *(intptr_t**)(hf.sp() - frame::sender_sp_offset); // we need to re-read fp because it may be an oop and we might have fixed the frame.
299     }
300     return frame(frame_sp, frame_sp, fp, hf.pc(), hf.cb(), hf.oop_map(), false); // TODO PERF : this computes deopt state; is it necessary?
301   }
302 }
303 
304 inline intptr_t* ThawBase::align(const frame& hf, intptr_t* frame_sp, frame& caller, bool bottom) {
305 #ifdef _LP64
306   if (((intptr_t)frame_sp & 0xf) != 0) {
307     assert(caller.is_interpreted_frame() || (bottom && hf.compiled_frame_stack_argsize() % 2 != 0), "");
308     frame_sp--;
309     caller.set_sp(caller.sp() - 1);
310   }
311   assert(is_aligned(frame_sp, frame::frame_alignment), "");
312 #endif
313 
314   return frame_sp;
315 }
316 
317 inline void ThawBase::patch_pd(frame& f, const frame& caller) {
318   patch_callee_link(caller, caller.fp());
319 }
320 
321 inline void ThawBase::patch_pd(frame& f, intptr_t* caller_sp) {
322   intptr_t* fp = caller_sp - frame::sender_sp_offset;
323   patch_callee_link(f, fp);
324 }
325 
326 inline intptr_t* ThawBase::push_cleanup_continuation() {
327   frame enterSpecial = new_entry_frame();
328   intptr_t* sp = enterSpecial.sp();
329 
330   sp[-1] = (intptr_t)ContinuationEntry::cleanup_pc();
331   sp[-2] = (intptr_t)enterSpecial.fp();
332 
333   log_develop_trace(continuations, preempt)("push_cleanup_continuation initial sp: " INTPTR_FORMAT " final sp: " INTPTR_FORMAT, p2i(sp + 2 * frame::metadata_words), p2i(sp));
334   return sp;
335 }
336 
337 inline intptr_t* ThawBase::push_preempt_adapter() {
338   frame enterSpecial = new_entry_frame();
339   intptr_t* sp = enterSpecial.sp();
340 
341   sp[-1] = (intptr_t)StubRoutines::cont_preempt_stub();
342 
343   log_develop_trace(continuations, preempt)("push_preempt_adapter initial sp: " INTPTR_FORMAT " final sp: " INTPTR_FORMAT, p2i(sp + 2 * frame::metadata_words), p2i(sp));
344   return sp;
345 }
346 
347 inline void ThawBase::derelativize_interpreted_frame_metadata(const frame& hf, const frame& f) {
348   // Make sure that last_sp is kept relativized.
349   assert((intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset) == f.unextended_sp(), "");
350 
351   // Make sure that monitor_block_top is still relativized.
352   assert(f.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
353 
354   // Make sure that extended_sp is kept relativized.
355   DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
356   DEBUG_ONLY(int extra_space = m->is_object_wait0() ? m->size_of_parameters() : 0;) // see comment in relativize_interpreted_frame_metadata()
357   assert((intptr_t*)f.at_relative(frame::interpreter_frame_extended_sp_offset) < f.unextended_sp() + extra_space, "");
358 }
359 
360 #endif // CPU_AARCH64_CONTINUATIONFREEZETHAW_AARCH64_INLINE_HPP