1 /*
  2  * Copyright (c) 2019, 2023, 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.
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 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::relativize_interpreted_frame_metadata(const frame& f, const frame& hf) {
133   assert(hf.fp() == hf.unextended_sp() + (f.fp() - f.unextended_sp()), "");
134   assert((f.at(frame::interpreter_frame_last_sp_offset) != 0)
135     || (f.unextended_sp() == f.sp()), "");
136   assert(f.fp() > (intptr_t*)f.at_relative(frame::interpreter_frame_initial_sp_offset), "");
137 
138   // on AARCH64, we may insert padding between the locals and the rest of the frame
139   // (see TemplateInterpreterGenerator::generate_normal_entry, and AbstractInterpreter::layout_activation)
140   // because we freeze the padding word (see recurse_freeze_interpreted_frame) in order to keep the same relativized
141   // locals value, we don't need to change the locals value here.
142 
143   // Make sure that last_sp is already relativized.
144   assert((intptr_t*)hf.at_relative(frame::interpreter_frame_last_sp_offset) == hf.unextended_sp(), "");
145 
146   // Make sure that monitor_block_top is already relativized.
147   assert(hf.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
148 
149   // extended_sp is already relativized by TemplateInterpreterGenerator::generate_normal_entry or
150   // AbstractInterpreter::layout_activation
151 
152   assert((hf.fp() - hf.unextended_sp()) == (f.fp() - f.unextended_sp()), "");
153   assert(hf.unextended_sp() == (intptr_t*)hf.at(frame::interpreter_frame_last_sp_offset), "");
154   assert(hf.unextended_sp() <= (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
155   assert(hf.unextended_sp() >  (intptr_t*)hf.at(frame::interpreter_frame_extended_sp_offset), "");
156   assert(hf.fp()            >  (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
157   assert(hf.fp()            <= (intptr_t*)hf.at(frame::interpreter_frame_locals_offset), "");
158 }
159 
160 inline void FreezeBase::set_top_frame_metadata_pd(const frame& hf) {
161   stackChunkOop chunk = _cont.tail();
162   assert(chunk->is_in_chunk(hf.sp() - 1), "");
163   assert(chunk->is_in_chunk(hf.sp() - frame::sender_sp_offset), "");
164 
165   *(hf.sp() - 1) = (intptr_t)hf.pc();
166 
167   intptr_t* fp_addr = hf.sp() - frame::sender_sp_offset;
168   *fp_addr = hf.is_interpreted_frame() ? (intptr_t)(hf.fp() - fp_addr)
169                                        : (intptr_t)hf.fp();
170 }
171 
172 inline void FreezeBase::patch_pd(frame& hf, const frame& caller) {
173   if (caller.is_interpreted_frame()) {
174     assert(!caller.is_empty(), "");
175     patch_callee_link_relative(caller, caller.fp());
176   } else {
177     // If we're the bottom-most frame frozen in this freeze, the caller might have stayed frozen in the chunk,
178     // and its oop-containing fp fixed. We've now just overwritten it, so we must patch it back to its value
179     // as read from the chunk.
180     patch_callee_link(caller, caller.fp());
181   }
182 }
183 
184 //////// Thaw
185 
186 // Fast path
187 
188 inline void ThawBase::prefetch_chunk_pd(void* start, int size) {
189   size <<= LogBytesPerWord;
190   Prefetch::read(start, size);
191   Prefetch::read(start, size - 64);
192 }
193 
194 template <typename ConfigT>
195 inline void Thaw<ConfigT>::patch_caller_links(intptr_t* sp, intptr_t* bottom) {
196   // Fast path depends on !PreserveFramePointer. See can_thaw_fast().
197   assert(!PreserveFramePointer, "Frame pointers need to be fixed");
198 }
199 
200 // Slow path
201 
202 inline frame ThawBase::new_entry_frame() {
203   intptr_t* sp = _cont.entrySP();
204   return frame(sp, sp, _cont.entryFP(), _cont.entryPC()); // TODO PERF: This finds code blob and computes deopt state
205 }
206 
207 template<typename FKind> frame ThawBase::new_stack_frame(const frame& hf, frame& caller, bool bottom) {
208   assert(FKind::is_instance(hf), "");
209   // The values in the returned frame object will be written into the callee's stack in patch.
210 
211   if (FKind::interpreted) {
212     intptr_t* heap_sp = hf.unextended_sp();
213     // If caller is interpreted it already made room for the callee arguments
214     int overlap = caller.is_interpreted_frame() ? ContinuationHelper::InterpretedFrame::stack_argsize(hf) : 0;
215     const int fsize = (int)(ContinuationHelper::InterpretedFrame::frame_bottom(hf) - hf.unextended_sp() - overlap);
216     const int locals = hf.interpreter_frame_method()->max_locals();
217     intptr_t* frame_sp = caller.unextended_sp() - fsize;
218     intptr_t* fp = frame_sp + (hf.fp() - heap_sp);
219     if ((intptr_t)fp % frame::frame_alignment != 0) {
220       fp--;
221       frame_sp--;
222       log_develop_trace(continuations)("Adding internal interpreted frame alignment");
223     }
224     DEBUG_ONLY(intptr_t* unextended_sp = fp + *hf.addr_at(frame::interpreter_frame_last_sp_offset);)
225     assert(frame_sp == unextended_sp, "");
226     caller.set_sp(fp + frame::sender_sp_offset);
227     frame f(frame_sp, frame_sp, fp, hf.pc());
228     // we need to set the locals so that the caller of new_stack_frame() can call
229     // ContinuationHelper::InterpretedFrame::frame_bottom
230     // copy relativized locals from the heap frame
231     *f.addr_at(frame::interpreter_frame_locals_offset) = *hf.addr_at(frame::interpreter_frame_locals_offset);
232     assert((intptr_t)f.fp() % frame::frame_alignment == 0, "");
233     return f;
234   } else {
235     int fsize = FKind::size(hf);
236     intptr_t* frame_sp = caller.unextended_sp() - fsize;
237     if (bottom || caller.is_interpreted_frame()) {
238       int argsize = hf.compiled_frame_stack_argsize();
239 
240       fsize += argsize;
241       frame_sp   -= argsize;
242       caller.set_sp(caller.sp() - argsize);
243       assert(caller.sp() == frame_sp + (fsize-argsize), "");
244 
245       frame_sp = align(hf, frame_sp, caller, bottom);
246     }
247 
248     assert(hf.cb() != nullptr, "");
249     assert(hf.oop_map() != nullptr, "");
250     intptr_t* fp;
251     if (PreserveFramePointer) {
252       // we need to recreate a "real" frame pointer, pointing into the stack
253       fp = frame_sp + FKind::size(hf) - frame::sender_sp_offset;
254     } else {
255       fp = FKind::stub
256         ? frame_sp + fsize - frame::sender_sp_offset // on AArch64, this value is used for the safepoint stub
257         : *(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.
258     }
259     return frame(frame_sp, frame_sp, fp, hf.pc(), hf.cb(), hf.oop_map(), false); // TODO PERF : this computes deopt state; is it necessary?
260   }
261 }
262 
263 inline intptr_t* ThawBase::align(const frame& hf, intptr_t* frame_sp, frame& caller, bool bottom) {
264 #ifdef _LP64
265   if (((intptr_t)frame_sp & 0xf) != 0) {
266     assert(caller.is_interpreted_frame() || (bottom && hf.compiled_frame_stack_argsize() % 2 != 0), "");
267     frame_sp--;
268     caller.set_sp(caller.sp() - 1);
269   }
270   assert(is_aligned(frame_sp, frame::frame_alignment), "");
271 #endif
272 
273   return frame_sp;
274 }
275 
276 inline void ThawBase::patch_pd(frame& f, const frame& caller) {
277   patch_callee_link(caller, caller.fp());
278 }
279 
280 inline void ThawBase::derelativize_interpreted_frame_metadata(const frame& hf, const frame& f) {
281   // Make sure that last_sp is kept relativized.
282   assert((intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset) == f.unextended_sp(), "");
283 
284   // Make sure that monitor_block_top is still relativized.
285   assert(f.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
286 
287   // Make sure that extended_sp is kept relativized.
288   assert((intptr_t*)f.at_relative(frame::interpreter_frame_extended_sp_offset) < f.unextended_sp(), "");
289 }
290 
291 #endif // CPU_AARCH64_CONTINUATIONFREEZETHAW_AARCH64_INLINE_HPP