1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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24
25 #ifndef CPU_RISCV_CONTINUATIONFREEZETHAW_RISCV_INLINE_HPP
26 #define CPU_RISCV_CONTINUATIONFREEZETHAW_RISCV_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 - 2) = *(heap_sp - 2);
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
63 intptr_t** link_addr = link_address<FKind>(f);
64 intptr_t* sender_sp = (intptr_t*)(link_addr + 2); // f.unextended_sp() + (fsize/wordSize); //
65 address sender_pc = (address) *(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> frame FreezeBase::new_heap_frame(frame& f, frame& caller, int size_adjust) {
78 assert(FKind::is_instance(f), "");
79 assert(!caller.is_interpreted_frame()
80 || caller.unextended_sp() == (intptr_t*)caller.at(frame::interpreter_frame_last_sp_offset), "");
81
82 intptr_t *sp, *fp; // sp is really our unextended_sp
83 if (FKind::interpreted) {
84 assert((intptr_t*)f.at(frame::interpreter_frame_last_sp_offset) == nullptr
85 || f.unextended_sp() == (intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset), "");
86 intptr_t locals_offset = *f.addr_at(frame::interpreter_frame_locals_offset);
87 // If the caller.is_empty(), i.e. we're freezing into an empty chunk, then we set
88 // the chunk's argsize in finalize_freeze and make room for it above the unextended_sp
89 bool overlap_caller = caller.is_interpreted_frame() || caller.is_empty();
90 fp = caller.unextended_sp() - 1 - locals_offset + (overlap_caller ? ContinuationHelper::InterpretedFrame::stack_argsize(f) : 0);
91 sp = fp - (f.fp() - f.unextended_sp());
92 assert(sp <= fp, "");
93 assert(fp <= caller.unextended_sp(), "");
94 caller.set_sp(fp + frame::sender_sp_offset);
95
96 assert(_cont.tail()->is_in_chunk(sp), "");
97
98 frame hf(sp, sp, fp, f.pc(), nullptr, nullptr, true /* on_heap */);
99 *hf.addr_at(frame::interpreter_frame_locals_offset) = locals_offset;
100 return hf;
101 } else {
102 // We need to re-read fp out of the frame because it may be an oop and we might have
103 // had a safepoint in finalize_freeze, after constructing f.
104 fp = *(intptr_t**)(f.sp() - 2);
105
106 int fsize = FKind::size(f);
107 sp = caller.unextended_sp() - fsize;
108 if (caller.is_interpreted_frame()) {
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 }
114 caller.set_sp(sp + fsize);
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 // On RISCV, we may insert padding between the locals and the rest of the frame
142 // (see TemplateInterpreterGenerator::generate_normal_entry, and AbstractInterpreter::layout_activation)
143 // because we freeze the padding word (see recurse_freeze_interpreted_frame) in order to keep the same relativized
144 // locals value, we don't need to change the locals value here.
145
146 // Make sure that last_sp is already relativized.
147 assert((intptr_t*)hf.at_relative(frame::interpreter_frame_last_sp_offset) == hf.unextended_sp(), "");
148
149 // Make sure that monitor_block_top is already relativized.
150 assert(hf.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
151
152 // extended_sp is already relativized by TemplateInterpreterGenerator::generate_normal_entry or
153 // AbstractInterpreter::layout_activation
154
155 // The interpreter native wrapper code adds space in the stack equal to size_of_parameters()
156 // after the fixed part of the frame. For wait0 this is equal to 3 words (this + long parameter).
157 // We adjust by this size since otherwise the saved last sp will be less than the extended_sp.
158 DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
159 DEBUG_ONLY(int extra_space = m->is_object_wait0() ? m->size_of_parameters() : 0;)
160
161 assert((hf.fp() - hf.unextended_sp()) == (f.fp() - f.unextended_sp()), "");
162 assert(hf.unextended_sp() == (intptr_t*)hf.at(frame::interpreter_frame_last_sp_offset), "");
163 assert(hf.unextended_sp() <= (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
164 assert(hf.unextended_sp() + extra_space > (intptr_t*)hf.at(frame::interpreter_frame_extended_sp_offset), "");
165 assert(hf.fp() > (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
166 #ifdef ASSERT
167 if (f.interpreter_frame_method()->max_locals() > 0) {
168 assert(hf.fp() <= (intptr_t*)hf.at(frame::interpreter_frame_locals_offset), "");
169 }
170 #endif
171 }
172
173 inline void FreezeBase::set_top_frame_metadata_pd(const frame& hf) {
174 stackChunkOop chunk = _cont.tail();
175 assert(chunk->is_in_chunk(hf.sp() - 1), "");
176 assert(chunk->is_in_chunk(hf.sp() - 2), "");
177
178 *(hf.sp() - 1) = (intptr_t)hf.pc();
179
180 intptr_t* fp_addr = hf.sp() - 2;
181 *fp_addr = hf.is_interpreted_frame() ? (intptr_t)(hf.fp() - fp_addr)
182 : (intptr_t)hf.fp();
183 }
184
185 inline void FreezeBase::patch_pd(frame& hf, const frame& caller, bool is_bottom_frame) {
186 if (caller.is_interpreted_frame()) {
187 assert(!caller.is_empty(), "");
188 patch_callee_link_relative(caller, caller.fp());
189 } else {
190 // If we're the bottom-most frame frozen in this freeze, the caller might have stayed frozen in the chunk,
191 // and its oop-containing fp fixed. We've now just overwritten it, so we must patch it back to its value
192 // as read from the chunk.
193 patch_callee_link(caller, caller.fp());
194 }
195 }
196
197 inline void FreezeBase::patch_pd_unused(intptr_t* sp) {
198 }
199
200 //////// Thaw
201
202 // Fast path
203
204 inline void ThawBase::prefetch_chunk_pd(void* start, int size) {
205 size <<= LogBytesPerWord;
206 Prefetch::read(start, size);
207 Prefetch::read(start, size - 64);
208 }
209
210 inline intptr_t* AnchorMark::anchor_mark_set_pd() {
211 intptr_t* sp = _top_frame.sp();
212 if (_top_frame.is_interpreted_frame()) {
213 // In case the top frame is interpreted we need to set up the anchor using
214 // the last_sp saved in the frame (remove possible alignment added while
215 // thawing, see ThawBase::finish_thaw()). We also clear last_sp to match
216 // the behavior when calling the VM from the interpreter (we check for this
217 // in FreezeBase::prepare_freeze_interpreted_top_frame, which can be reached
218 // if preempting again at redo_vmcall()).
219 _last_sp_from_frame = _top_frame.interpreter_frame_last_sp();
220 assert(_last_sp_from_frame != nullptr, "");
221 _top_frame.interpreter_frame_set_last_sp(nullptr);
222 if (sp != _last_sp_from_frame) {
223 // We need to move up return pc and fp. They will be read next in
224 // set_anchor() and set as _last_Java_pc and _last_Java_fp respectively.
225 _last_sp_from_frame[-1] = (intptr_t)_top_frame.pc();
226 _last_sp_from_frame[-2] = (intptr_t)_top_frame.fp();
227 }
228 _is_interpreted = true;
229 sp = _last_sp_from_frame;
230 }
231 return sp;
232 }
233
234 inline void AnchorMark::anchor_mark_clear_pd() {
235 if (_is_interpreted) {
236 // Restore last_sp_from_frame and possibly overwritten pc.
237 _top_frame.interpreter_frame_set_last_sp(_last_sp_from_frame);
238 intptr_t* sp = _top_frame.sp();
239 if (sp != _last_sp_from_frame) {
240 sp[-1] = (intptr_t)_top_frame.pc();
241 }
242 }
243 }
244
245 template <typename ConfigT>
246 inline void Thaw<ConfigT>::patch_caller_links(intptr_t* sp, intptr_t* bottom) {
247 // Fast path depends on !PreserveFramePointer. See can_thaw_fast().
248 assert(!PreserveFramePointer, "Frame pointers need to be fixed");
249 }
250
251 // Slow path
252
253 inline frame ThawBase::new_entry_frame() {
254 intptr_t* sp = _cont.entrySP();
255 // TODO PERF: This finds code blob and computes deopt state
256 return frame(sp, sp, _cont.entryFP(), _cont.entryPC());
257 }
258
259 template<typename FKind> frame ThawBase::new_stack_frame(const frame& hf, frame& caller, bool bottom, int size_adjust) {
260 assert(FKind::is_instance(hf), "");
261 // The values in the returned frame object will be written into the callee's stack in patch.
262
263 if (FKind::interpreted) {
264 intptr_t* heap_sp = hf.unextended_sp();
265 // If caller is interpreted it already made room for the callee arguments
266 int overlap = caller.is_interpreted_frame() ? ContinuationHelper::InterpretedFrame::stack_argsize(hf) : 0;
267 const int fsize = (int)(ContinuationHelper::InterpretedFrame::frame_bottom(hf) - hf.unextended_sp() - overlap);
268 intptr_t* frame_sp = caller.unextended_sp() - fsize;
269 intptr_t* fp = frame_sp + (hf.fp() - heap_sp);
270 if ((intptr_t)fp % frame::frame_alignment != 0) {
271 fp--;
272 frame_sp--;
273 log_develop_trace(continuations)("Adding internal interpreted frame alignment");
274 }
275 DEBUG_ONLY(intptr_t* unextended_sp = fp + *hf.addr_at(frame::interpreter_frame_last_sp_offset);)
276 assert(frame_sp == unextended_sp, "");
277 caller.set_sp(fp + frame::sender_sp_offset);
278 frame f(frame_sp, frame_sp, fp, hf.pc());
279 // we need to set the locals so that the caller of new_stack_frame() can call
280 // ContinuationHelper::InterpretedFrame::frame_bottom
281 // copy relativized locals from the heap frame
282 *f.addr_at(frame::interpreter_frame_locals_offset) = *hf.addr_at(frame::interpreter_frame_locals_offset);
283 assert((intptr_t)f.fp() % frame::frame_alignment == 0, "");
284 return f;
285 } else {
286 int fsize = FKind::size(hf);
287 intptr_t* frame_sp = caller.unextended_sp() - fsize;
288 if (bottom || caller.is_interpreted_frame()) {
289 int argsize = FKind::stack_argsize(hf);
290
291 fsize += argsize;
292 frame_sp -= argsize;
293 caller.set_sp(caller.sp() - argsize);
294 assert(caller.sp() == frame_sp + (fsize-argsize), "");
295
296 frame_sp = align(hf, frame_sp, caller, bottom);
297 }
298
299 assert(hf.cb() != nullptr, "");
300 assert(hf.oop_map() != nullptr, "");
301 intptr_t* fp;
302 if (PreserveFramePointer) {
303 // we need to recreate a "real" frame pointer, pointing into the stack
304 fp = frame_sp + FKind::size(hf) - frame::sender_sp_offset;
305 } else {
306 fp = FKind::stub || FKind::native
307 // fp always points to the address above the pushed return pc. We need correct address.
308 ? frame_sp + fsize - frame::sender_sp_offset
309 // we need to re-read fp because it may be an oop and we might have fixed the frame.
310 : *(intptr_t**)(hf.sp() - 2);
311 }
312 // TODO PERF : this computes deopt state; is it necessary?
313 return frame(frame_sp, frame_sp, fp, hf.pc(), hf.cb(), hf.oop_map(), false);
314 }
315 }
316
317 inline intptr_t* ThawBase::align(const frame& hf, intptr_t* frame_sp, frame& caller, bool bottom) {
318 #ifdef _LP64
319 if (((intptr_t)frame_sp & 0xf) != 0) {
320 assert(caller.is_interpreted_frame() || (bottom && hf.compiled_frame_stack_argsize() % 2 != 0), "");
321 frame_sp--;
322 caller.set_sp(caller.sp() - 1);
323 }
324 assert(is_aligned(frame_sp, frame::frame_alignment), "");
325 #endif
326
327 return frame_sp;
328 }
329
330 inline void ThawBase::patch_pd(frame& f, const frame& caller) {
331 patch_callee_link(caller, caller.fp());
332 }
333
334 inline void ThawBase::patch_pd(frame& f, intptr_t* caller_sp) {
335 intptr_t* fp = caller_sp - frame::sender_sp_offset;
336 patch_callee_link(f, fp);
337 }
338
339 inline intptr_t* ThawBase::push_cleanup_continuation() {
340 frame enterSpecial = new_entry_frame();
341 intptr_t* sp = enterSpecial.sp();
342
343 // We only need to set the return pc. fp will be restored back in gen_continuation_enter().
344 sp[-1] = (intptr_t)ContinuationEntry::cleanup_pc();
345 return sp;
346 }
347
348 inline intptr_t* ThawBase::push_preempt_adapter() {
349 frame enterSpecial = new_entry_frame();
350 intptr_t* sp = enterSpecial.sp();
351
352 // We only need to set the return pc. fp will be restored back in generate_cont_preempt_stub().
353 sp[-1] = (intptr_t)StubRoutines::cont_preempt_stub();
354 return sp;
355 }
356
357 inline void ThawBase::derelativize_interpreted_frame_metadata(const frame& hf, const frame& f) {
358 // Make sure that last_sp is kept relativized.
359 assert((intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset) == f.unextended_sp(), "");
360
361 // Make sure that monitor_block_top is still relativized.
362 assert(f.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
363
364 DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
365 DEBUG_ONLY(int extra_space = m->is_object_wait0() ? m->size_of_parameters() : 0;) // see comment in relativize_interpreted_frame_metadata()
366
367 // Make sure that extended_sp is kept relativized.
368 assert((intptr_t*)f.at_relative(frame::interpreter_frame_extended_sp_offset) < f.unextended_sp() + extra_space, "");
369 }
370
371 #endif // CPU_RISCV_CONTINUATIONFREEZETHAW_RISCV_INLINE_HPP