1 /*
2 * Copyright (c) 2019, 2025, 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
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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.
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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
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23 */
24
25 #ifndef CPU_X86_CONTINUATIONFREEZETHAW_X86_INLINE_HPP
26 #define CPU_X86_CONTINUATIONFREEZETHAW_X86_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 inline void patch_callee_link(const frame& f, intptr_t* fp) {
34 *ContinuationHelper::Frame::callee_link_address(f) = fp;
35 }
36
37 inline void patch_callee_link_relative(const frame& f, intptr_t* fp) {
38 intptr_t* la = (intptr_t*)ContinuationHelper::Frame::callee_link_address(f);
39 intptr_t new_value = fp - la;
40 *la = new_value;
41 }
42
43 ////// Freeze
44
45 // Fast path
46
47 inline void FreezeBase::patch_stack_pd(intptr_t* frame_sp, intptr_t* heap_sp) {
48 // copy the spilled rbp from the heap to the stack
49 *(frame_sp - frame::sender_sp_offset) = *(heap_sp - frame::sender_sp_offset);
50 }
51
52 // Slow path
53
54 template<typename FKind>
55 inline frame FreezeBase::sender(const frame& f) {
56 assert(FKind::is_instance(f), "");
57 if (FKind::interpreted) {
58 return frame(f.sender_sp(), f.interpreter_frame_sender_sp(), f.link(), f.sender_pc());
59 }
60
61 frame::CompiledFramePointers cfp = f.compiled_frame_details();
62
63 int slot = 0;
64 CodeBlob* sender_cb = CodeCache::find_blob_and_oopmap(*cfp.sender_pc_addr, slot);
65
66 return sender_cb != nullptr
67 ? frame(cfp.sender_sp, cfp.sender_sp, *cfp.saved_fp_addr, *cfp.sender_pc_addr, sender_cb,
68 slot == -1 ? nullptr : sender_cb->oop_map_for_slot(slot, *cfp.sender_pc_addr), false)
69 : frame(cfp.sender_sp, cfp.sender_sp, *cfp.saved_fp_addr, *cfp.sender_pc_addr);
70 }
71
72 template<typename FKind>
73 frame FreezeBase::new_heap_frame(frame& f, frame& caller, int size_adjust) {
74 assert(FKind::is_instance(f), "");
75 assert(!caller.is_interpreted_frame()
76 || caller.unextended_sp() == (intptr_t*)caller.at(frame::interpreter_frame_last_sp_offset), "");
77
78 intptr_t *sp, *fp; // sp is really our unextended_sp
79 if (FKind::interpreted) {
80 assert((intptr_t*)f.at_relative_or_null(frame::interpreter_frame_last_sp_offset) == nullptr
81 || f.unextended_sp() == (intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset), "");
82 intptr_t locals_offset = *f.addr_at(frame::interpreter_frame_locals_offset);
83 // If the caller.is_empty(), i.e. we're freezing into an empty chunk, then we set
84 // the chunk's argsize in finalize_freeze and make room for it above the unextended_sp
85 bool overlap_caller = caller.is_interpreted_frame() || caller.is_empty();
86 fp = caller.unextended_sp() - 1 - locals_offset + (overlap_caller ? ContinuationHelper::InterpretedFrame::stack_argsize(f) : 0);
87 sp = fp - (f.fp() - f.unextended_sp());
88 assert(sp <= fp, "");
89 assert(fp <= caller.unextended_sp(), "");
90 caller.set_sp(fp + frame::sender_sp_offset);
91
92 assert(_cont.tail()->is_in_chunk(sp), "");
93
94 frame hf(sp, sp, fp, f.pc(), nullptr, nullptr, true /* on_heap */);
95 // copy relativized locals from the stack frame
96 *hf.addr_at(frame::interpreter_frame_locals_offset) = locals_offset;
97 return hf;
98 } else {
99 // For a compiled frame we need to re-read fp out of the frame because it may be an
100 // oop and we might have had a safepoint in finalize_freeze, after constructing f.
101 // For stub/native frames the value is not used while frozen, and will be constructed again
102 // when thawing the frame (see ThawBase::new_stack_frame). We use a special bad address to
103 // help with debugging, particularly when inspecting frames and identifying invalid accesses.
104 fp = FKind::compiled ? *(intptr_t**)(f.sp() - frame::sender_sp_offset) : (intptr_t*)badAddressVal;
105
106 int fsize = FKind::size(f);
107 sp = caller.unextended_sp() - fsize - size_adjust;
108 if (caller.is_interpreted_frame() && size_adjust == 0) {
109 // If the caller is interpreted, our stackargs are not supposed to overlap with it
110 // so we make more room by moving sp down by argsize
111 int argsize = FKind::stack_argsize(f);
112 sp -= argsize;
113 caller.set_sp(sp + fsize);
114 }
115
116 assert(_cont.tail()->is_in_chunk(sp), "");
117
118 return frame(sp, sp, fp, f.pc(), nullptr, nullptr, true /* on_heap */);
119 }
120 }
121
122 void FreezeBase::adjust_interpreted_frame_unextended_sp(frame& f) {
123 assert((f.at(frame::interpreter_frame_last_sp_offset) != 0) || (f.unextended_sp() == f.sp()), "");
124 intptr_t* real_unextended_sp = (intptr_t*)f.at_relative_or_null(frame::interpreter_frame_last_sp_offset);
125 if (real_unextended_sp != nullptr) {
126 f.set_unextended_sp(real_unextended_sp); // can be null at a safepoint
127 }
128 }
129
130 inline void FreezeBase::prepare_freeze_interpreted_top_frame(frame& f) {
131 assert(f.interpreter_frame_last_sp() == nullptr, "should be null for top frame");
132 f.interpreter_frame_set_last_sp(f.unextended_sp());
133 }
134
135 inline void FreezeBase::relativize_interpreted_frame_metadata(const frame& f, const frame& hf) {
136 assert(hf.fp() == hf.unextended_sp() + (f.fp() - f.unextended_sp()), "");
137 assert((f.at(frame::interpreter_frame_last_sp_offset) != 0)
138 || (f.unextended_sp() == f.sp()), "");
139 assert(f.fp() > (intptr_t*)f.at_relative(frame::interpreter_frame_initial_sp_offset), "");
140
141 // Make sure that last_sp is already relativized.
142 assert((intptr_t*)hf.at_relative(frame::interpreter_frame_last_sp_offset) == hf.unextended_sp(), "");
143
144 // Make sure that locals is already relativized.
145 DEBUG_ONLY(Method* m = f.interpreter_frame_method();)
146 // Frames for native methods have 2 extra words (temp oop/result handler) before fixed part of frame.
147 DEBUG_ONLY(int max_locals = !m->is_native() ? m->max_locals() : m->size_of_parameters() + 2;)
148 assert((*hf.addr_at(frame::interpreter_frame_locals_offset) == frame::sender_sp_offset + max_locals - 1), "");
149
150 // Make sure that monitor_block_top is already relativized.
151 assert(hf.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
152
153 assert((hf.fp() - hf.unextended_sp()) == (f.fp() - f.unextended_sp()), "");
154 assert(hf.unextended_sp() == (intptr_t*)hf.at(frame::interpreter_frame_last_sp_offset), "");
155 assert(hf.unextended_sp() <= (intptr_t*)hf.at(frame::interpreter_frame_initial_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 address frame_pc = hf.pc();
166
167 *(hf.sp() - 1) = (intptr_t)hf.pc();
168
169 intptr_t* fp_addr = hf.sp() - frame::sender_sp_offset;
170 *fp_addr = hf.is_interpreted_frame() ? (intptr_t)(hf.fp() - fp_addr)
171 : (intptr_t)hf.fp();
172 assert(frame_pc == ContinuationHelper::Frame::real_pc(hf), "");
173 }
174
175 inline void FreezeBase::patch_pd(frame& hf, const frame& caller, bool is_bottom_frame) {
176 if (caller.is_interpreted_frame()) {
177 assert(!caller.is_empty(), "");
178 patch_callee_link_relative(caller, caller.fp());
179 } else if (is_bottom_frame && caller.pc() != nullptr) {
180 assert(caller.is_compiled_frame(), "");
181 // If we're the bottom-most frame frozen in this freeze, the caller might have stayed frozen in the chunk,
182 // and its oop-containing fp fixed. We've now just overwritten it, so we must patch it back to its value
183 // as read from the chunk.
184 patch_callee_link(caller, caller.fp());
185 }
186 }
187
188 inline void FreezeBase::patch_pd_unused(intptr_t* sp) {
189 intptr_t* fp_addr = sp - frame::sender_sp_offset;
190 *fp_addr = badAddressVal;
191 }
192
193 inline intptr_t* AnchorMark::anchor_mark_set_pd() {
194 intptr_t* sp = _top_frame.sp();
195 if (_top_frame.is_interpreted_frame()) {
196 // In case the top frame is interpreted we need to set up the anchor using
197 // the last_sp saved in the frame (remove possible alignment added while
198 // thawing, see ThawBase::finish_thaw()). We also clear last_sp to match
199 // the behavior when calling the VM from the interpreter (we check for this
200 // in FreezeBase::prepare_freeze_interpreted_top_frame, which can be reached
201 // if preempting again at redo_vmcall()).
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 // We need to move up return pc and fp. They will be read next in
207 // set_anchor() and set as _last_Java_pc and _last_Java_fp respectively.
208 _last_sp_from_frame[-1] = (intptr_t)_top_frame.pc();
209 _last_sp_from_frame[-2] = (intptr_t)_top_frame.fp();
210 }
211 _is_interpreted = true;
212 sp = _last_sp_from_frame;
213 }
214 return sp;
215 }
216
217 inline void AnchorMark::anchor_mark_clear_pd() {
218 if (_is_interpreted) {
219 // Restore last_sp_from_frame and possibly overwritten pc.
220 _top_frame.interpreter_frame_set_last_sp(_last_sp_from_frame);
221 intptr_t* sp = _top_frame.sp();
222 if (sp != _last_sp_from_frame) {
223 sp[-1] = (intptr_t)_top_frame.pc();
224 }
225 }
226 }
227
228 //////// Thaw
229
230 // Fast path
231
232 inline void ThawBase::prefetch_chunk_pd(void* start, int size) {
233 size <<= LogBytesPerWord;
234 Prefetch::read(start, size);
235 Prefetch::read(start, size - 64);
236 }
237
238 template <typename ConfigT>
239 inline void Thaw<ConfigT>::patch_caller_links(intptr_t* sp, intptr_t* bottom) {
240 // Fast path depends on !PreserveFramePointer. See can_thaw_fast().
241 assert(!PreserveFramePointer, "Frame pointers need to be fixed");
242 }
243
244 // Slow path
245
246 inline frame ThawBase::new_entry_frame() {
247 intptr_t* sp = _cont.entrySP();
248 return frame(sp, sp, _cont.entryFP(), _cont.entryPC()); // TODO PERF: This finds code blob and computes deopt state
249 }
250
251 template<typename FKind> frame ThawBase::new_stack_frame(const frame& hf, frame& caller, bool bottom, int size_adjust) {
252 assert(FKind::is_instance(hf), "");
253 // The values in the returned frame object will be written into the callee's stack in patch.
254
255 if (FKind::interpreted) {
256 intptr_t* heap_sp = hf.unextended_sp();
257 // If caller is interpreted it already made room for the callee arguments
258 int overlap = caller.is_interpreted_frame() ? ContinuationHelper::InterpretedFrame::stack_argsize(hf) : 0;
259 const int fsize = (int)(ContinuationHelper::InterpretedFrame::frame_bottom(hf) - hf.unextended_sp() - overlap);
260 intptr_t* frame_sp = caller.unextended_sp() - fsize;
261 intptr_t* fp = frame_sp + (hf.fp() - heap_sp);
262 DEBUG_ONLY(intptr_t* unextended_sp = fp + *hf.addr_at(frame::interpreter_frame_last_sp_offset);)
263 assert(frame_sp == unextended_sp, "");
264 caller.set_sp(fp + frame::sender_sp_offset);
265 frame f(frame_sp, frame_sp, fp, hf.pc());
266 // we need to set the locals so that the caller of new_stack_frame() can call
267 // ContinuationHelper::InterpretedFrame::frame_bottom
268 intptr_t locals_offset = *hf.addr_at(frame::interpreter_frame_locals_offset);
269 DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
270 // Frames for native methods have 2 extra words (temp oop/result handler) before fixed part of frame.
271 DEBUG_ONLY(const int max_locals = !m->is_native() ? m->max_locals() : m->size_of_parameters() + 2;)
272 assert((int)locals_offset == frame::sender_sp_offset + max_locals - 1, "");
273 // copy relativized locals from the heap frame
274 *f.addr_at(frame::interpreter_frame_locals_offset) = locals_offset;
275 return f;
276 } else {
277 int fsize = FKind::size(hf);
278 intptr_t* frame_sp = caller.unextended_sp() - fsize - size_adjust;
279 if (bottom || caller.is_interpreted_frame()) {
280 if (size_adjust == 0) {
281 int argsize = FKind::stack_argsize(hf);
282 frame_sp -= argsize;
283 }
284 frame_sp = align(hf, frame_sp, caller, bottom);
285 caller.set_sp(frame_sp + fsize + size_adjust);
286 }
287 assert(is_aligned(frame_sp, frame::frame_alignment), "");
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 + fsize - 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 if (((intptr_t)frame_sp & 0xf) != 0) {
306 assert(caller.is_interpreted_frame() || (bottom && hf.compiled_frame_stack_argsize() % 2 != 0), "");
307 frame_sp--;
308 }
309 assert(is_aligned(frame_sp, frame::frame_alignment), "");
310 return frame_sp;
311 }
312
313 inline void ThawBase::patch_pd(frame& f, const frame& caller) {
314 if (caller.is_interpreted_frame() || PreserveFramePointer) {
315 patch_callee_link(caller, caller.fp());
316 }
317 }
318
319 inline void ThawBase::patch_pd(frame& f, intptr_t* caller_sp) {
320 intptr_t* fp = caller_sp - frame::sender_sp_offset;
321 patch_callee_link(f, fp);
322 }
323
324 inline intptr_t* ThawBase::push_cleanup_continuation() {
325 frame enterSpecial = new_entry_frame();
326 intptr_t* sp = enterSpecial.sp();
327
328 // We only need to set the return pc. rbp will be restored back in gen_continuation_enter().
329 sp[-1] = (intptr_t)ContinuationEntry::cleanup_pc();
330 return sp;
331 }
332
333 inline intptr_t* ThawBase::push_preempt_adapter() {
334 frame enterSpecial = new_entry_frame();
335 intptr_t* sp = enterSpecial.sp();
336
337 // We only need to set the return pc. rbp will be restored back in generate_cont_preempt_stub().
338 sp[-1] = (intptr_t)StubRoutines::cont_preempt_stub();
339 return sp;
340 }
341
342 inline void ThawBase::derelativize_interpreted_frame_metadata(const frame& hf, const frame& f) {
343 // Make sure that last_sp is kept relativized.
344 assert((intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset) == f.unextended_sp(), "");
345
346 // Make sure that monitor_block_top is still relativized.
347 assert(f.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
348 }
349
350 #endif // CPU_X86_CONTINUATIONFREEZE_THAW_X86_INLINE_HPP