1 /*
  2  * Copyright (c) 2019, 2024, Oracle and/or its affiliates. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  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).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  *
 23  */
 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 //////// Thaw
196 
197 // Fast path
198 
199 inline void ThawBase::prefetch_chunk_pd(void* start, int size) {
200   size <<= LogBytesPerWord;
201   Prefetch::read(start, size);
202   Prefetch::read(start, size - 64);
203 }
204 
205 template <typename ConfigT>
206 inline void Thaw<ConfigT>::patch_caller_links(intptr_t* sp, intptr_t* bottom) {
207   // Fast path depends on !PreserveFramePointer. See can_thaw_fast().
208   assert(!PreserveFramePointer, "Frame pointers need to be fixed");
209 }
210 
211 // Slow path
212 
213 inline frame ThawBase::new_entry_frame() {
214   intptr_t* sp = _cont.entrySP();
215   return frame(sp, sp, _cont.entryFP(), _cont.entryPC()); // TODO PERF: This finds code blob and computes deopt state
216 }
217 
218 template<typename FKind> frame ThawBase::new_stack_frame(const frame& hf, frame& caller, bool bottom) {
219   assert(FKind::is_instance(hf), "");
220   // The values in the returned frame object will be written into the callee's stack in patch.
221 
222   if (FKind::interpreted) {
223     intptr_t* heap_sp = hf.unextended_sp();
224     // If caller is interpreted it already made room for the callee arguments
225     int overlap = caller.is_interpreted_frame() ? ContinuationHelper::InterpretedFrame::stack_argsize(hf) : 0;
226     const int fsize = (int)(ContinuationHelper::InterpretedFrame::frame_bottom(hf) - hf.unextended_sp() - overlap);
227     intptr_t* frame_sp = caller.unextended_sp() - fsize;
228     intptr_t* fp = frame_sp + (hf.fp() - heap_sp);
229     if ((intptr_t)fp % frame::frame_alignment != 0) {
230       fp--;
231       frame_sp--;
232       log_develop_trace(continuations)("Adding internal interpreted frame alignment");
233     }
234     DEBUG_ONLY(intptr_t* unextended_sp = fp + *hf.addr_at(frame::interpreter_frame_last_sp_offset);)
235     assert(frame_sp == unextended_sp, "");
236     caller.set_sp(fp + frame::sender_sp_offset);
237     frame f(frame_sp, frame_sp, fp, hf.pc());
238     // we need to set the locals so that the caller of new_stack_frame() can call
239     // ContinuationHelper::InterpretedFrame::frame_bottom
240     // copy relativized locals from the heap frame
241     *f.addr_at(frame::interpreter_frame_locals_offset) = *hf.addr_at(frame::interpreter_frame_locals_offset);
242     assert((intptr_t)f.fp() % frame::frame_alignment == 0, "");
243     return f;
244   } else {
245     int fsize = FKind::size(hf);
246     intptr_t* frame_sp = caller.unextended_sp() - fsize;
247     if (bottom || caller.is_interpreted_frame()) {
248       int argsize = FKind::stack_argsize(hf);
249 
250       fsize += argsize;
251       frame_sp   -= argsize;
252       caller.set_sp(caller.sp() - argsize);
253       assert(caller.sp() == frame_sp + (fsize-argsize), "");
254 
255       frame_sp = align(hf, frame_sp, caller, bottom);
256     }
257 
258     assert(hf.cb() != nullptr, "");
259     assert(hf.oop_map() != nullptr, "");
260     intptr_t* fp;
261     if (PreserveFramePointer) {
262       // we need to recreate a "real" frame pointer, pointing into the stack
263       fp = frame_sp + FKind::size(hf) - frame::sender_sp_offset;
264     } else {
265       fp = FKind::stub || FKind::native
266         ? frame_sp + fsize - frame::sender_sp_offset // fp always points to the address below the pushed return pc. We need correct address.
267         : *(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.
268     }
269     return frame(frame_sp, frame_sp, fp, hf.pc(), hf.cb(), hf.oop_map(), false); // TODO PERF : this computes deopt state; is it necessary?
270   }
271 }
272 
273 inline intptr_t* ThawBase::align(const frame& hf, intptr_t* frame_sp, frame& caller, bool bottom) {
274 #ifdef _LP64
275   if (((intptr_t)frame_sp & 0xf) != 0) {
276     assert(caller.is_interpreted_frame() || (bottom && hf.compiled_frame_stack_argsize() % 2 != 0), "");
277     frame_sp--;
278     caller.set_sp(caller.sp() - 1);
279   }
280   assert(is_aligned(frame_sp, frame::frame_alignment), "");
281 #endif
282 
283   return frame_sp;
284 }
285 
286 inline void ThawBase::patch_pd(frame& f, const frame& caller) {
287   patch_callee_link(caller, caller.fp());
288 }
289 
290 inline void ThawBase::patch_pd(frame& f, intptr_t* caller_sp) {
291   intptr_t* fp = caller_sp - frame::sender_sp_offset;
292   patch_callee_link(f, fp);
293 }
294 
295 inline intptr_t* ThawBase::push_cleanup_continuation() {
296   frame enterSpecial = new_entry_frame();
297   intptr_t* sp = enterSpecial.sp();
298 
299   sp[-1] = (intptr_t)ContinuationEntry::cleanup_pc();
300   sp[-2] = (intptr_t)enterSpecial.fp();
301 
302   log_develop_trace(continuations, preempt)("push_cleanup_continuation initial sp: " INTPTR_FORMAT " final sp: " INTPTR_FORMAT, p2i(sp + 2 * frame::metadata_words), p2i(sp));
303   return sp;
304 }
305 
306 inline void ThawBase::derelativize_interpreted_frame_metadata(const frame& hf, const frame& f) {
307   // Make sure that last_sp is kept relativized.
308   assert((intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset) == f.unextended_sp(), "");
309 
310   // Make sure that monitor_block_top is still relativized.
311   assert(f.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
312 
313   // Make sure that extended_sp is kept relativized.
314   DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
315   DEBUG_ONLY(int extra_space = m->is_object_wait0() ? m->size_of_parameters() : 0;) // see comment in relativize_interpreted_frame_metadata()
316   assert((intptr_t*)f.at_relative(frame::interpreter_frame_extended_sp_offset) < f.unextended_sp() + extra_space, "");
317 }
318 
319 #endif // CPU_AARCH64_CONTINUATIONFREEZETHAW_AARCH64_INLINE_HPP