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
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.
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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 intptr_t** link_addr = link_address<FKind>(f);
61
62 intptr_t* sender_sp = (intptr_t*)(link_addr + frame::sender_sp_offset); // f.unextended_sp() + (fsize/wordSize); //
63 address sender_pc = (address) *(sender_sp-1);
64 assert(sender_sp != f.sp(), "must have changed");
65
66 int slot = 0;
67 CodeBlob* sender_cb = CodeCache::find_blob_and_oopmap(sender_pc, slot);
68 return sender_cb != nullptr
69 ? frame(sender_sp, sender_sp, *link_addr, sender_pc, sender_cb,
70 slot == -1 ? nullptr : sender_cb->oop_map_for_slot(slot, sender_pc), false)
71 : frame(sender_sp, sender_sp, *link_addr, sender_pc);
72 }
73
74 template<typename FKind>
75 frame FreezeBase::new_heap_frame(frame& f, frame& caller) {
76 assert(FKind::is_instance(f), "");
77 assert(!caller.is_interpreted_frame()
78 || caller.unextended_sp() == (intptr_t*)caller.at(frame::interpreter_frame_last_sp_offset), "");
79
80 intptr_t *sp, *fp; // sp is really our unextended_sp
81 if (FKind::interpreted) {
82 assert((intptr_t*)f.at_relative_or_null(frame::interpreter_frame_last_sp_offset) == nullptr
83 || f.unextended_sp() == (intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset), "");
84 intptr_t locals_offset = *f.addr_at(frame::interpreter_frame_locals_offset);
85 // If the caller.is_empty(), i.e. we're freezing into an empty chunk, then we set
86 // the chunk's argsize in finalize_freeze and make room for it above the unextended_sp
87 bool overlap_caller = caller.is_interpreted_frame() || caller.is_empty();
88 fp = caller.unextended_sp() - 1 - locals_offset + (overlap_caller ? ContinuationHelper::InterpretedFrame::stack_argsize(f) : 0);
89 sp = fp - (f.fp() - f.unextended_sp());
90 assert(sp <= fp, "");
91 assert(fp <= caller.unextended_sp(), "");
92 caller.set_sp(fp + frame::sender_sp_offset);
93
94 assert(_cont.tail()->is_in_chunk(sp), "");
95
96 frame hf(sp, sp, fp, f.pc(), nullptr, nullptr, true /* on_heap */);
97 // copy relativized locals from the stack frame
98 *hf.addr_at(frame::interpreter_frame_locals_offset) = locals_offset;
99 return hf;
100 } else {
101 // For a compiled frame we need to re-read fp out of the frame because it may be an
102 // oop and we might have had a safepoint in finalize_freeze, after constructing f.
103 // For stub/native frames the value is not used while frozen, and will be constructed again
104 // when thawing the frame (see ThawBase::new_stack_frame). We use a special bad address to
105 // help with debugging, particularly when inspecting frames and identifying invalid accesses.
106 fp = FKind::compiled ? *(intptr_t**)(f.sp() - frame::sender_sp_offset) : (intptr_t*)badAddressVal;
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 // 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 locals is already relativized.
147 DEBUG_ONLY(Method* m = f.interpreter_frame_method();)
148 // Frames for native methods have 2 extra words (temp oop/result handler) before fixed part of frame.
149 DEBUG_ONLY(int max_locals = !m->is_native() ? m->max_locals() : m->size_of_parameters() + 2;)
150 assert((*hf.addr_at(frame::interpreter_frame_locals_offset) == frame::sender_sp_offset + max_locals - 1), "");
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 assert((hf.fp() - hf.unextended_sp()) == (f.fp() - f.unextended_sp()), "");
156 assert(hf.unextended_sp() == (intptr_t*)hf.at(frame::interpreter_frame_last_sp_offset), "");
157 assert(hf.unextended_sp() <= (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
158 assert(hf.fp() > (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
159 assert(hf.fp() <= (intptr_t*)hf.at(frame::interpreter_frame_locals_offset), "");
160 }
161
162 inline void FreezeBase::set_top_frame_metadata_pd(const frame& hf) {
163 stackChunkOop chunk = _cont.tail();
164 assert(chunk->is_in_chunk(hf.sp() - 1), "");
165 assert(chunk->is_in_chunk(hf.sp() - frame::sender_sp_offset), "");
166
167 address frame_pc = hf.pc();
168
169 *(hf.sp() - 1) = (intptr_t)hf.pc();
170
171 intptr_t* fp_addr = hf.sp() - frame::sender_sp_offset;
172 *fp_addr = hf.is_interpreted_frame() ? (intptr_t)(hf.fp() - fp_addr)
173 : (intptr_t)hf.fp();
174 assert(frame_pc == ContinuationHelper::Frame::real_pc(hf), "");
175 }
176
177 inline void FreezeBase::patch_pd(frame& hf, const frame& caller) {
178 if (caller.is_interpreted_frame()) {
179 assert(!caller.is_empty(), "");
180 patch_callee_link_relative(caller, caller.fp());
181 } else {
182 // If we're the bottom-most frame frozen in this freeze, the caller might have stayed frozen in the chunk,
183 // and its oop-containing fp fixed. We've now just overwritten it, so we must patch it back to its value
184 // as read from the chunk.
185 patch_callee_link(caller, caller.fp());
186 }
187 }
188
189 inline void FreezeBase::patch_pd_unused(intptr_t* sp) {
190 intptr_t* fp_addr = sp - frame::sender_sp_offset;
191 *fp_addr = badAddressVal;
192 }
193
194 //////// Thaw
195
196 // Fast path
197
198 inline void ThawBase::prefetch_chunk_pd(void* start, int size) {
199 size <<= LogBytesPerWord;
200 Prefetch::read(start, size);
201 Prefetch::read(start, size - 64);
202 }
203
204 template <typename ConfigT>
205 inline void Thaw<ConfigT>::patch_caller_links(intptr_t* sp, intptr_t* bottom) {
206 // Fast path depends on !PreserveFramePointer. See can_thaw_fast().
207 assert(!PreserveFramePointer, "Frame pointers need to be fixed");
208 }
209
210 // Slow path
211
212 inline frame ThawBase::new_entry_frame() {
213 intptr_t* sp = _cont.entrySP();
214 return frame(sp, sp, _cont.entryFP(), _cont.entryPC()); // TODO PERF: This finds code blob and computes deopt state
215 }
216
217 template<typename FKind> frame ThawBase::new_stack_frame(const frame& hf, frame& caller, bool bottom) {
218 assert(FKind::is_instance(hf), "");
219 // The values in the returned frame object will be written into the callee's stack in patch.
220
221 if (FKind::interpreted) {
222 intptr_t* heap_sp = hf.unextended_sp();
223 // If caller is interpreted it already made room for the callee arguments
224 int overlap = caller.is_interpreted_frame() ? ContinuationHelper::InterpretedFrame::stack_argsize(hf) : 0;
225 const int fsize = (int)(ContinuationHelper::InterpretedFrame::frame_bottom(hf) - hf.unextended_sp() - overlap);
226 intptr_t* frame_sp = caller.unextended_sp() - fsize;
227 intptr_t* fp = frame_sp + (hf.fp() - heap_sp);
228 DEBUG_ONLY(intptr_t* unextended_sp = fp + *hf.addr_at(frame::interpreter_frame_last_sp_offset);)
229 assert(frame_sp == unextended_sp, "");
230 caller.set_sp(fp + frame::sender_sp_offset);
231 frame f(frame_sp, frame_sp, fp, hf.pc());
232 // we need to set the locals so that the caller of new_stack_frame() can call
233 // ContinuationHelper::InterpretedFrame::frame_bottom
234 intptr_t locals_offset = *hf.addr_at(frame::interpreter_frame_locals_offset);
235 DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
236 // Frames for native methods have 2 extra words (temp oop/result handler) before fixed part of frame.
237 DEBUG_ONLY(const int max_locals = !m->is_native() ? m->max_locals() : m->size_of_parameters() + 2;)
238 assert((int)locals_offset == frame::sender_sp_offset + max_locals - 1, "");
239 // copy relativized locals from the heap frame
240 *f.addr_at(frame::interpreter_frame_locals_offset) = locals_offset;
241 return f;
242 } else {
243 int fsize = FKind::size(hf);
244 intptr_t* frame_sp = caller.unextended_sp() - fsize;
245 if (bottom || caller.is_interpreted_frame()) {
246 int argsize = FKind::stack_argsize(hf);
247
248 fsize += argsize;
249 frame_sp -= argsize;
250 caller.set_sp(caller.sp() - argsize);
251 assert(caller.sp() == frame_sp + (fsize-argsize), "");
252
253 frame_sp = align(hf, frame_sp, caller, bottom);
254 }
255
256 assert(hf.cb() != nullptr, "");
257 assert(hf.oop_map() != nullptr, "");
258 intptr_t* fp;
259 if (PreserveFramePointer) {
260 // we need to recreate a "real" frame pointer, pointing into the stack
261 fp = frame_sp + FKind::size(hf) - frame::sender_sp_offset;
262 } else {
263 fp = FKind::stub || FKind::native
264 ? frame_sp + fsize - frame::sender_sp_offset // fp always points to the address below the pushed return pc. We need correct address.
265 : *(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.
266 }
267 return frame(frame_sp, frame_sp, fp, hf.pc(), hf.cb(), hf.oop_map(), false); // TODO PERF : this computes deopt state; is it necessary?
268 }
269 }
270
271 inline intptr_t* ThawBase::align(const frame& hf, intptr_t* frame_sp, frame& caller, bool bottom) {
272 if (((intptr_t)frame_sp & 0xf) != 0) {
273 assert(caller.is_interpreted_frame() || (bottom && hf.compiled_frame_stack_argsize() % 2 != 0), "");
274 frame_sp--;
275 caller.set_sp(caller.sp() - 1);
276 }
277 assert(is_aligned(frame_sp, frame::frame_alignment), "");
278 return frame_sp;
279 }
280
281 inline void ThawBase::patch_pd(frame& f, const frame& caller) {
282 patch_callee_link(caller, caller.fp());
283 }
284
285 inline void ThawBase::patch_pd(frame& f, intptr_t* caller_sp) {
286 intptr_t* fp = caller_sp - frame::sender_sp_offset;
287 patch_callee_link(f, fp);
288 }
289
290 inline intptr_t* ThawBase::push_cleanup_continuation() {
291 frame enterSpecial = new_entry_frame();
292 intptr_t* sp = enterSpecial.sp();
293
294 sp[-1] = (intptr_t)ContinuationEntry::cleanup_pc();
295 sp[-2] = (intptr_t)enterSpecial.fp();
296
297 log_develop_trace(continuations, preempt)("push_cleanup_continuation initial sp: " INTPTR_FORMAT " final sp: " INTPTR_FORMAT, p2i(sp + 2 * frame::metadata_words), p2i(sp));
298 return sp;
299 }
300
301 inline void ThawBase::derelativize_interpreted_frame_metadata(const frame& hf, const frame& f) {
302 // Make sure that last_sp is kept relativized.
303 assert((intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset) == f.unextended_sp(), "");
304
305 // Make sure that monitor_block_top is still relativized.
306 assert(f.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
307 }
308
309 #endif // CPU_X86_CONTINUATIONFREEZE_THAW_X86_INLINE_HPP