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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 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).
 14  *
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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(const frame& f) {
133   assert(*f.addr_at(frame::interpreter_frame_last_sp_offset) == 0, "should be null for top frame");
134   intptr_t* lspp = f.addr_at(frame::interpreter_frame_last_sp_offset);
135   *lspp = f.unextended_sp() - f.fp();
136 }
137 
138 inline void FreezeBase::relativize_interpreted_frame_metadata(const frame& f, const frame& hf) {
139   assert(hf.fp() == hf.unextended_sp() + (f.fp() - f.unextended_sp()), "");
140   assert((f.at(frame::interpreter_frame_last_sp_offset) != 0)
141     || (f.unextended_sp() == f.sp()), "");
142   assert(f.fp() > (intptr_t*)f.at_relative(frame::interpreter_frame_initial_sp_offset), "");
143 
144   // on AARCH64, we may insert padding between the locals and the rest of the frame
145   // (see TemplateInterpreterGenerator::generate_normal_entry, and AbstractInterpreter::layout_activation)
146   // because we freeze the padding word (see recurse_freeze_interpreted_frame) in order to keep the same relativized
147   // locals value, we don't need to change the locals value here.
148 
149   // Make sure that last_sp is already relativized.
150   assert((intptr_t*)hf.at_relative(frame::interpreter_frame_last_sp_offset) == hf.unextended_sp(), "");
151 
152   // Make sure that monitor_block_top is already relativized.
153   assert(hf.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
154 
155   // extended_sp is already relativized by TemplateInterpreterGenerator::generate_normal_entry or
156   // AbstractInterpreter::layout_activation
157 
158   // The interpreter native wrapper code adds space in the stack equal to size_of_parameters()
159   // after the fixed part of the frame. For wait0 this is equal to 3 words (this + long parameter).
160   // We adjust by this size since otherwise the saved last sp will be less than the extended_sp.
161   DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
162   DEBUG_ONLY(int extra_space = m->is_object_wait0() ? m->size_of_parameters() : 0;)
163 
164   assert((hf.fp() - hf.unextended_sp()) == (f.fp() - f.unextended_sp()), "");
165   assert(hf.unextended_sp() == (intptr_t*)hf.at(frame::interpreter_frame_last_sp_offset), "");
166   assert(hf.unextended_sp() <= (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
167   assert(hf.unextended_sp() + extra_space >  (intptr_t*)hf.at(frame::interpreter_frame_extended_sp_offset), "");
168   assert(hf.fp()            >  (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
169   assert(hf.fp()            <= (intptr_t*)hf.at(frame::interpreter_frame_locals_offset), "");
170 }
171 
172 inline void FreezeBase::set_top_frame_metadata_pd(const frame& hf) {
173   stackChunkOop chunk = _cont.tail();
174   assert(chunk->is_in_chunk(hf.sp() - 1), "");
175   assert(chunk->is_in_chunk(hf.sp() - frame::sender_sp_offset), "");
176 
177   *(hf.sp() - 1) = (intptr_t)hf.pc();
178 
179   intptr_t* fp_addr = hf.sp() - frame::sender_sp_offset;
180   *fp_addr = hf.is_interpreted_frame() ? (intptr_t)(hf.fp() - fp_addr)
181                                        : (intptr_t)hf.fp();
182 }
183 
184 inline void FreezeBase::patch_pd(frame& hf, const frame& caller) {
185   if (caller.is_interpreted_frame()) {
186     assert(!caller.is_empty(), "");
187     patch_callee_link_relative(caller, caller.fp());
188   } else {
189     // If we're the bottom-most frame frozen in this freeze, the caller might have stayed frozen in the chunk,
190     // and its oop-containing fp fixed. We've now just overwritten it, so we must patch it back to its value
191     // as read from the chunk.
192     patch_callee_link(caller, caller.fp());
193   }
194 }
195 
196 //////// Thaw
197 
198 // Fast path
199 
200 inline void ThawBase::prefetch_chunk_pd(void* start, int size) {
201   size <<= LogBytesPerWord;
202   Prefetch::read(start, size);
203   Prefetch::read(start, size - 64);
204 }
205 
206 template <typename ConfigT>
207 inline void Thaw<ConfigT>::patch_caller_links(intptr_t* sp, intptr_t* bottom) {
208   // Fast path depends on !PreserveFramePointer. See can_thaw_fast().
209   assert(!PreserveFramePointer, "Frame pointers need to be fixed");
210 }
211 
212 // Slow path
213 
214 inline frame ThawBase::new_entry_frame() {
215   intptr_t* sp = _cont.entrySP();
216   return frame(sp, sp, _cont.entryFP(), _cont.entryPC()); // TODO PERF: This finds code blob and computes deopt state
217 }
218 
219 template<typename FKind> frame ThawBase::new_stack_frame(const frame& hf, frame& caller, bool bottom) {
220   assert(FKind::is_instance(hf), "");
221   // The values in the returned frame object will be written into the callee's stack in patch.
222 
223   if (FKind::interpreted) {
224     intptr_t* heap_sp = hf.unextended_sp();
225     // If caller is interpreted it already made room for the callee arguments
226     int overlap = caller.is_interpreted_frame() ? ContinuationHelper::InterpretedFrame::stack_argsize(hf) : 0;
227     const int fsize = (int)(ContinuationHelper::InterpretedFrame::frame_bottom(hf) - hf.unextended_sp() - overlap);
228     intptr_t* frame_sp = caller.unextended_sp() - fsize;
229     intptr_t* fp = frame_sp + (hf.fp() - heap_sp);
230     if ((intptr_t)fp % frame::frame_alignment != 0) {
231       fp--;
232       frame_sp--;
233       log_develop_trace(continuations)("Adding internal interpreted frame alignment");
234     }
235     DEBUG_ONLY(intptr_t* unextended_sp = fp + *hf.addr_at(frame::interpreter_frame_last_sp_offset);)
236     assert(frame_sp == unextended_sp, "");
237     caller.set_sp(fp + frame::sender_sp_offset);
238     frame f(frame_sp, frame_sp, fp, hf.pc());
239     // we need to set the locals so that the caller of new_stack_frame() can call
240     // ContinuationHelper::InterpretedFrame::frame_bottom
241     // copy relativized locals from the heap frame
242     *f.addr_at(frame::interpreter_frame_locals_offset) = *hf.addr_at(frame::interpreter_frame_locals_offset);
243     assert((intptr_t)f.fp() % frame::frame_alignment == 0, "");
244     return f;
245   } else {
246     int fsize = FKind::size(hf);
247     intptr_t* frame_sp = caller.unextended_sp() - fsize;
248     if (bottom || caller.is_interpreted_frame()) {
249       int argsize = FKind::stack_argsize(hf);
250 
251       fsize += argsize;
252       frame_sp   -= argsize;
253       caller.set_sp(caller.sp() - argsize);
254       assert(caller.sp() == frame_sp + (fsize-argsize), "");
255 
256       frame_sp = align(hf, frame_sp, caller, bottom);
257     }
258 
259     assert(hf.cb() != nullptr, "");
260     assert(hf.oop_map() != nullptr, "");
261     intptr_t* fp;
262     if (PreserveFramePointer) {
263       // we need to recreate a "real" frame pointer, pointing into the stack
264       fp = frame_sp + FKind::size(hf) - frame::sender_sp_offset;
265     } else {
266       fp = FKind::stub || FKind::native
267         ? frame_sp + fsize - frame::sender_sp_offset // fp always points to the address below the pushed return pc. We need correct address.
268         : *(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.
269     }
270     return frame(frame_sp, frame_sp, fp, hf.pc(), hf.cb(), hf.oop_map(), false); // TODO PERF : this computes deopt state; is it necessary?
271   }
272 }
273 
274 inline intptr_t* ThawBase::align(const frame& hf, intptr_t* frame_sp, frame& caller, bool bottom) {
275 #ifdef _LP64
276   if (((intptr_t)frame_sp & 0xf) != 0) {
277     assert(caller.is_interpreted_frame() || (bottom && hf.compiled_frame_stack_argsize() % 2 != 0), "");
278     frame_sp--;
279     caller.set_sp(caller.sp() - 1);
280   }
281   assert(is_aligned(frame_sp, frame::frame_alignment), "");
282 #endif
283 
284   return frame_sp;
285 }
286 
287 inline void ThawBase::patch_pd(frame& f, const frame& caller) {
288   patch_callee_link(caller, caller.fp());
289 }
290 
291 inline void ThawBase::patch_pd(frame& f, intptr_t* caller_sp) {
292   Unimplemented();
293 }
294 
295 inline void ThawBase::fix_native_return_pc_pd(frame& top) {
296   // Nothing to do since the last pc saved before making the call to
297   // JVM_MonitorWait() was already set to the correct resume pc. Just
298   // do some sanity check.
299 #ifdef ASSERT
300   Method* method = top.is_interpreted_frame() ? top.interpreter_frame_method() : CodeCache::find_blob(top.pc())->as_nmethod()->method();
301   assert(method->is_object_wait0(), "");
302 #endif
303 }
304 
305 inline intptr_t* ThawBase::push_resume_adapter(frame& top) {
306   intptr_t* sp = top.sp();
307   CodeBlob* cb = top.cb();
308 
309 #ifdef ASSERT
310   RegisterMap map(JavaThread::current(),
311                   RegisterMap::UpdateMap::skip,
312                   RegisterMap::ProcessFrames::skip,
313                   RegisterMap::WalkContinuation::skip);
314   frame caller = top.sender(&map);
315   intptr_t link_addr = (intptr_t)ContinuationHelper::Frame::callee_link_address(caller);
316   assert(sp[-2] == link_addr, "wrong link address: " INTPTR_FORMAT " != " INTPTR_FORMAT, sp[-2], link_addr);
317 #endif
318 
319   bool interpreted = top.is_interpreted_frame();
320   if (!interpreted && cb->frame_size() == 2) {
321     // C2 runtime stub case. For aarch64 the real size of the c2 runtime stub is 2 words bigger
322     // than what we think, i.e. size is 4. This is because the _last_Java_sp is not set to the
323     // sp right before making the call to the VM, but rather it is artificially set 2 words above
324     // this real sp so that we can store the return address at last_Java_sp[-1], and keep this
325     // property where we can retrieve the last_Java_pc from the last_Java_sp. But that means that
326     // once we return to the runtime stub, the code will adjust sp according to this real size.
327     // So we must adjust the frame size back here. We just copy lr/rfp again. These 2 top words
328     // will be the ones popped in generate_cont_preempt_rerun_compiler_adapter(). The other 2 words
329     // will just be discarded once back in the runtime stub (add sp, sp, #0x10).
330     sp -= 2;
331     sp[-2] = sp[0];
332     sp[-1] = sp[1];
333   }
334 
335   intptr_t* fp = sp - frame::sender_sp_offset;
336   address pc = interpreted ? Interpreter::cont_resume_interpreter_adapter()
337                            : StubRoutines::cont_resume_compiler_adapter();
338 
339   sp -= frame::metadata_words;
340   *(address*)(sp - frame::sender_sp_ret_address_offset()) = pc;
341   *(intptr_t**)(sp - frame::sender_sp_offset) = fp;
342 
343   log_develop_trace(continuations, preempt)("push_resume_%s_adapter() initial sp: " INTPTR_FORMAT " final sp: " INTPTR_FORMAT " fp: " INTPTR_FORMAT,
344     interpreted ? "interpreter" : "compiler", p2i(sp + frame::metadata_words), p2i(sp), p2i(fp));
345   return sp;
346 }
347 
348 inline intptr_t* ThawBase::push_resume_monitor_operation(stackChunkOop chunk) {
349   frame enterSpecial = new_entry_frame();
350   intptr_t* sp = enterSpecial.sp();
351 
352   // First push the return barrier frame
353   sp -= frame::metadata_words;
354   sp[1] = (intptr_t)StubRoutines::cont_returnBarrier();
355   sp[0] = (intptr_t)enterSpecial.fp();
356 
357   // Now push the ObjectWaiter*
358   sp -= frame::metadata_words;
359   sp[1] = (intptr_t)chunk->object_waiter(); // alignment
360   sp[0] = (intptr_t)chunk->object_waiter();
361 
362   // Finally arrange to return to the resume_monitor_operation stub
363   sp[-1] = (intptr_t)StubRoutines::cont_resume_monitor_operation();
364   sp[-2] = (intptr_t)enterSpecial.fp();
365   log_develop_trace(continuations, preempt)("push_resume_monitor_operation initial sp: " INTPTR_FORMAT " final sp: " INTPTR_FORMAT, p2i(sp + 2 * frame::metadata_words), p2i(sp));
366   return sp;
367 }
368 
369 inline void ThawBase::derelativize_interpreted_frame_metadata(const frame& hf, const frame& f) {
370   // Make sure that last_sp is kept relativized.
371   assert((intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset) == f.unextended_sp(), "");
372 
373   // Make sure that monitor_block_top is still relativized.
374   assert(f.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
375 
376   // Make sure that extended_sp is kept relativized.
377   DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
378   DEBUG_ONLY(int extra_space = m->is_object_wait0() ? m->size_of_parameters() : 0;) // see comment in relativize_interpreted_frame_metadata()
379   assert((intptr_t*)f.at_relative(frame::interpreter_frame_extended_sp_offset) < f.unextended_sp() + extra_space, "");
380 }
381 
382 #endif // CPU_AARCH64_CONTINUATIONFREEZETHAW_AARCH64_INLINE_HPP