1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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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>
78 frame FreezeBase::new_heap_frame(frame& f, frame& caller, int size_adjust) {
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 *hf.addr_at(frame::interpreter_frame_locals_offset) = locals_offset;
101 return hf;
102 } else {
103 // We need to re-read fp out of the frame because it may be an oop and we might have
104 // had a safepoint in finalize_freeze, after constructing f.
105 fp = *(intptr_t**)(f.sp() - 2);
106
107 int fsize = FKind::size(f);
108 sp = caller.unextended_sp() - fsize - size_adjust;
109 if (caller.is_interpreted_frame() && size_adjust == 0) {
110 // If the caller is interpreted, our stackargs are not supposed to overlap with it
111 // so we make more room by moving sp down by argsize
112 int argsize = FKind::stack_argsize(f);
113 sp -= argsize;
114 caller.set_sp(sp + fsize);
115 }
116
117 assert(_cont.tail()->is_in_chunk(sp), "");
118
119 return frame(sp, sp, fp, f.pc(), nullptr, nullptr, true /* on_heap */);
120 }
121 }
122
123 void FreezeBase::adjust_interpreted_frame_unextended_sp(frame& f) {
124 assert((f.at(frame::interpreter_frame_last_sp_offset) != 0) || (f.unextended_sp() == f.sp()), "");
125 intptr_t* real_unextended_sp = (intptr_t*)f.at_relative_or_null(frame::interpreter_frame_last_sp_offset);
126 if (real_unextended_sp != nullptr) {
127 f.set_unextended_sp(real_unextended_sp); // can be null at a safepoint
128 }
129 }
130
131 inline void FreezeBase::prepare_freeze_interpreted_top_frame(frame& f) {
132 assert(f.interpreter_frame_last_sp() == nullptr, "should be null for top frame");
133 f.interpreter_frame_set_last_sp(f.unextended_sp());
134 }
135
136 inline void FreezeBase::relativize_interpreted_frame_metadata(const frame& f, const frame& hf) {
137 assert(hf.fp() == hf.unextended_sp() + (f.fp() - f.unextended_sp()), "");
138 assert((f.at(frame::interpreter_frame_last_sp_offset) != 0)
139 || (f.unextended_sp() == f.sp()), "");
140 assert(f.fp() > (intptr_t*)f.at_relative(frame::interpreter_frame_initial_sp_offset), "");
141
142 // On RISCV, we may insert padding between the locals and the rest of the frame
143 // (see TemplateInterpreterGenerator::generate_normal_entry, and AbstractInterpreter::layout_activation)
144 // because we freeze the padding word (see recurse_freeze_interpreted_frame) in order to keep the same relativized
145 // locals value, we don't need to change the locals value here.
146
147 // Make sure that last_sp is already relativized.
148 assert((intptr_t*)hf.at_relative(frame::interpreter_frame_last_sp_offset) == hf.unextended_sp(), "");
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 // extended_sp is already relativized by TemplateInterpreterGenerator::generate_normal_entry or
154 // AbstractInterpreter::layout_activation
155
156 // The interpreter native wrapper code adds space in the stack equal to size_of_parameters()
157 // after the fixed part of the frame. For wait0 this is equal to 3 words (this + long parameter).
158 // We adjust by this size since otherwise the saved last sp will be less than the extended_sp.
159 DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
160 DEBUG_ONLY(int extra_space = m->is_object_wait0() ? m->size_of_parameters() : 0;)
161
162 assert((hf.fp() - hf.unextended_sp()) == (f.fp() - f.unextended_sp()), "");
163 assert(hf.unextended_sp() == (intptr_t*)hf.at(frame::interpreter_frame_last_sp_offset), "");
164 assert(hf.unextended_sp() <= (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
165 assert(hf.unextended_sp() + extra_space > (intptr_t*)hf.at(frame::interpreter_frame_extended_sp_offset), "");
166 assert(hf.fp() > (intptr_t*)hf.at(frame::interpreter_frame_initial_sp_offset), "");
167 #ifdef ASSERT
168 if (f.interpreter_frame_method()->max_locals() > 0) {
169 assert(hf.fp() <= (intptr_t*)hf.at(frame::interpreter_frame_locals_offset), "");
170 }
171 #endif
172 }
173
174 inline void FreezeBase::set_top_frame_metadata_pd(const frame& hf) {
175 stackChunkOop chunk = _cont.tail();
176 assert(chunk->is_in_chunk(hf.sp() - 1), "");
177 assert(chunk->is_in_chunk(hf.sp() - 2), "");
178
179 *(hf.sp() - 1) = (intptr_t)hf.pc();
180
181 intptr_t* fp_addr = hf.sp() - 2;
182 *fp_addr = hf.is_interpreted_frame() ? (intptr_t)(hf.fp() - fp_addr)
183 : (intptr_t)hf.fp();
184 }
185
186 inline void FreezeBase::patch_pd(frame& hf, const frame& caller, bool is_bottom_frame) {
187 if (caller.is_interpreted_frame()) {
188 assert(!caller.is_empty(), "");
189 patch_callee_link_relative(caller, caller.fp());
190 } else if (is_bottom_frame && caller.pc() != nullptr) {
191 assert(caller.is_compiled_frame(), "");
192 // If we're the bottom-most frame frozen in this freeze, the caller might have stayed frozen in the chunk,
193 // and its oop-containing fp fixed. We've now just overwritten it, so we must patch it back to its value
194 // as read from the chunk.
195 patch_callee_link(caller, caller.fp());
196 }
197 }
198
199 inline void FreezeBase::patch_pd_unused(intptr_t* sp) {
200 }
201
202 //////// Thaw
203
204 // Fast path
205
206 inline void ThawBase::prefetch_chunk_pd(void* start, int size) {
207 size <<= LogBytesPerWord;
208 Prefetch::read(start, size);
209 Prefetch::read(start, size - 64);
210 }
211
212 inline intptr_t* AnchorMark::anchor_mark_set_pd() {
213 intptr_t* sp = _top_frame.sp();
214 if (_top_frame.is_interpreted_frame()) {
215 // In case the top frame is interpreted we need to set up the anchor using
216 // the last_sp saved in the frame (remove possible alignment added while
217 // thawing, see ThawBase::finish_thaw()). We also clear last_sp to match
218 // the behavior when calling the VM from the interpreter (we check for this
219 // in FreezeBase::prepare_freeze_interpreted_top_frame, which can be reached
220 // if preempting again at redo_vmcall()).
221 _last_sp_from_frame = _top_frame.interpreter_frame_last_sp();
222 assert(_last_sp_from_frame != nullptr, "");
223 _top_frame.interpreter_frame_set_last_sp(nullptr);
224 if (sp != _last_sp_from_frame) {
225 // We need to move up return pc and fp. They will be read next in
226 // set_anchor() and set as _last_Java_pc and _last_Java_fp respectively.
227 _last_sp_from_frame[-1] = (intptr_t)_top_frame.pc();
228 _last_sp_from_frame[-2] = (intptr_t)_top_frame.fp();
229 }
230 _is_interpreted = true;
231 sp = _last_sp_from_frame;
232 }
233 return sp;
234 }
235
236 inline void AnchorMark::anchor_mark_clear_pd() {
237 if (_is_interpreted) {
238 // Restore last_sp_from_frame and possibly overwritten pc.
239 _top_frame.interpreter_frame_set_last_sp(_last_sp_from_frame);
240 intptr_t* sp = _top_frame.sp();
241 if (sp != _last_sp_from_frame) {
242 sp[-1] = (intptr_t)_top_frame.pc();
243 }
244 }
245 }
246
247 template <typename ConfigT>
248 inline void Thaw<ConfigT>::patch_caller_links(intptr_t* sp, intptr_t* bottom) {
249 // Fast path depends on !PreserveFramePointer. See can_thaw_fast().
250 assert(!PreserveFramePointer, "Frame pointers need to be fixed");
251 }
252
253 // Slow path
254
255 inline frame ThawBase::new_entry_frame() {
256 intptr_t* sp = _cont.entrySP();
257 // TODO PERF: This finds code blob and computes deopt state
258 return frame(sp, sp, _cont.entryFP(), _cont.entryPC());
259 }
260
261 template<typename FKind>
262 frame ThawBase::new_stack_frame(const frame& hf, frame& caller, bool bottom, int size_adjust) {
263 assert(FKind::is_instance(hf), "");
264 // The values in the returned frame object will be written into the callee's stack in patch.
265
266 if (FKind::interpreted) {
267 intptr_t* heap_sp = hf.unextended_sp();
268 // If caller is interpreted it already made room for the callee arguments
269 int overlap = caller.is_interpreted_frame() ? ContinuationHelper::InterpretedFrame::stack_argsize(hf) : 0;
270 const int fsize = (int)(ContinuationHelper::InterpretedFrame::frame_bottom(hf) - hf.unextended_sp() - overlap);
271 intptr_t* frame_sp = caller.unextended_sp() - fsize;
272 intptr_t* fp = frame_sp + (hf.fp() - heap_sp);
273 if ((intptr_t)fp % frame::frame_alignment != 0) {
274 fp--;
275 frame_sp--;
276 log_develop_trace(continuations)("Adding internal interpreted frame alignment");
277 }
278 DEBUG_ONLY(intptr_t* unextended_sp = fp + *hf.addr_at(frame::interpreter_frame_last_sp_offset);)
279 assert(frame_sp == unextended_sp, "");
280 caller.set_sp(fp + frame::sender_sp_offset);
281 frame f(frame_sp, frame_sp, fp, hf.pc());
282 // we need to set the locals so that the caller of new_stack_frame() can call
283 // ContinuationHelper::InterpretedFrame::frame_bottom
284 // copy relativized locals from the heap frame
285 *f.addr_at(frame::interpreter_frame_locals_offset) = *hf.addr_at(frame::interpreter_frame_locals_offset);
286 assert((intptr_t)f.fp() % frame::frame_alignment == 0, "");
287 return f;
288 } else {
289 int fsize = FKind::size(hf);
290 intptr_t* frame_sp = caller.unextended_sp() - fsize - size_adjust;
291 if (bottom || caller.is_interpreted_frame()) {
292 if (size_adjust == 0) {
293 int argsize = FKind::stack_argsize(hf);
294 frame_sp -= argsize;
295 }
296 frame_sp = align(hf, frame_sp, caller, bottom);
297 caller.set_sp(frame_sp + fsize + size_adjust);
298 }
299 assert(is_aligned(frame_sp, frame::frame_alignment), "");
300
301 assert(hf.cb() != nullptr, "");
302 assert(hf.oop_map() != nullptr, "");
303 intptr_t* fp;
304 if (PreserveFramePointer) {
305 // we need to recreate a "real" frame pointer, pointing into the stack
306 fp = frame_sp + fsize - frame::sender_sp_offset;
307 } else {
308 fp = FKind::stub || FKind::native
309 // fp always points to the address above the pushed return pc. We need correct address.
310 ? frame_sp + fsize - frame::sender_sp_offset
311 // we need to re-read fp because it may be an oop and we might have fixed the frame.
312 : *(intptr_t**)(hf.sp() - 2);
313 }
314 // TODO PERF : this computes deopt state; is it necessary?
315 return frame(frame_sp, frame_sp, fp, hf.pc(), hf.cb(), hf.oop_map(), false);
316 }
317 }
318
319 inline intptr_t* ThawBase::align(const frame& hf, intptr_t* frame_sp, frame& caller, bool bottom) {
320 #ifdef _LP64
321 if (((intptr_t)frame_sp & 0xf) != 0) {
322 assert(caller.is_interpreted_frame() || (bottom && hf.compiled_frame_stack_argsize() % 2 != 0), "");
323 frame_sp--;
324 }
325 assert(is_aligned(frame_sp, frame::frame_alignment), "");
326 #endif
327 return frame_sp;
328 }
329
330 inline void ThawBase::patch_pd(frame& f, const frame& caller) {
331 if (caller.is_interpreted_frame() || PreserveFramePointer) {
332 patch_callee_link(caller, caller.fp());
333 }
334 }
335
336 inline void ThawBase::patch_pd(frame& f, intptr_t* caller_sp) {
337 intptr_t* fp = caller_sp - frame::sender_sp_offset;
338 patch_callee_link(f, fp);
339 }
340
341 inline intptr_t* ThawBase::push_cleanup_continuation() {
342 frame enterSpecial = new_entry_frame();
343 intptr_t* sp = enterSpecial.sp();
344
345 // We only need to set the return pc. fp will be restored back in gen_continuation_enter().
346 sp[-1] = (intptr_t)ContinuationEntry::cleanup_pc();
347 return sp;
348 }
349
350 inline intptr_t* ThawBase::push_preempt_adapter() {
351 frame enterSpecial = new_entry_frame();
352 intptr_t* sp = enterSpecial.sp();
353
354 // We only need to set the return pc. fp will be restored back in generate_cont_preempt_stub().
355 sp[-1] = (intptr_t)StubRoutines::cont_preempt_stub();
356 return sp;
357 }
358
359 inline void ThawBase::derelativize_interpreted_frame_metadata(const frame& hf, const frame& f) {
360 // Make sure that last_sp is kept relativized.
361 assert((intptr_t*)f.at_relative(frame::interpreter_frame_last_sp_offset) == f.unextended_sp(), "");
362
363 // Make sure that monitor_block_top is still relativized.
364 assert(f.at_absolute(frame::interpreter_frame_monitor_block_top_offset) <= frame::interpreter_frame_initial_sp_offset, "");
365
366 DEBUG_ONLY(Method* m = hf.interpreter_frame_method();)
367 DEBUG_ONLY(int extra_space = m->is_object_wait0() ? m->size_of_parameters() : 0;) // see comment in relativize_interpreted_frame_metadata()
368
369 // Make sure that extended_sp is kept relativized.
370 assert((intptr_t*)f.at_relative(frame::interpreter_frame_extended_sp_offset) < f.unextended_sp() + extra_space, "");
371 }
372
373 #endif // CPU_RISCV_CONTINUATIONFREEZETHAW_RISCV_INLINE_HPP