1/*
2 * Copyright (c) 1997, 2017, 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 SHARE_VM_CODE_COMPILEDIC_HPP
26#define SHARE_VM_CODE_COMPILEDIC_HPP
27
28#include "code/nativeInst.hpp"
29#include "interpreter/linkResolver.hpp"
30#include "oops/compiledICHolder.hpp"
31
32//-----------------------------------------------------------------------------
33// The CompiledIC represents a compiled inline cache.
34//
35// In order to make patching of the inline cache MT-safe, we only allow the following
36// transitions (when not at a safepoint):
37//
38//
39//         [1] --<--  Clean -->---  [1]
40//            /       (null)      \
41//           /                     \      /-<-\
42//          /          [2]          \    /     \
43//      Interpreted  ---------> Monomorphic     | [3]
44//  (CompiledICHolder*)            (Klass*)     |
45//          \                        /   \     /
46//       [4] \                      / [4] \->-/
47//            \->-  Megamorphic -<-/
48//                  (Method*)
49//
50// The text in paranteses () refere to the value of the inline cache receiver (mov instruction)
51//
52// The numbers in square brackets refere to the kind of transition:
53// [1]: Initial fixup. Receiver it found from debug information
54// [2]: Compilation of a method
55// [3]: Recompilation of a method (note: only entry is changed. The Klass* must stay the same)
56// [4]: Inline cache miss. We go directly to megamorphic call.
57//
58// The class automatically inserts transition stubs (using the InlineCacheBuffer) when an MT-unsafe
59// transition is made to a stub.
60//
61class CompiledIC;
62class ICStub;
63
64class CompiledICInfo : public StackObj {
65 private:
66  address _entry;              // entry point for call
67  void*   _cached_value;         // Value of cached_value (either in stub or inline cache)
68  bool    _is_icholder;          // Is the cached value a CompiledICHolder*
69  bool    _is_optimized;       // it is an optimized virtual call (i.e., can be statically bound)
70  bool    _to_interpreter;     // Call it to interpreter
71  bool    _to_aot;             // Call it to aot code
72  bool    _release_icholder;
73 public:
74  address entry() const        { return _entry; }
75  Metadata*    cached_metadata() const         { assert(!_is_icholder, ""); return (Metadata*)_cached_value; }
76  CompiledICHolder*    claim_cached_icholder() {
77    assert(_is_icholder, "");
78    assert(_cached_value != NULL, "must be non-NULL");
79    _release_icholder = false;
80    CompiledICHolder* icholder = (CompiledICHolder*)_cached_value;
81    icholder->claim();
82    return icholder;
83  }
84  bool    is_optimized() const { return _is_optimized; }
85  bool  to_interpreter() const { return _to_interpreter; }
86  bool          to_aot() const { return _to_aot; }
87
88  void set_compiled_entry(address entry, Klass* klass, bool is_optimized) {
89    _entry      = entry;
90    _cached_value = (void*)klass;
91    _to_interpreter = false;
92    _to_aot = false;
93    _is_icholder = false;
94    _is_optimized = is_optimized;
95    _release_icholder = false;
96  }
97
98  void set_interpreter_entry(address entry, Method* method) {
99    _entry      = entry;
100    _cached_value = (void*)method;
101    _to_interpreter = true;
102    _to_aot = false;
103    _is_icholder = false;
104    _is_optimized = true;
105    _release_icholder = false;
106  }
107
108  void set_aot_entry(address entry, Method* method) {
109    _entry      = entry;
110    _cached_value = (void*)method;
111    _to_interpreter = false;
112    _to_aot = true;
113    _is_icholder = false;
114    _is_optimized = true;
115    _release_icholder = false;
116  }
117
118  void set_icholder_entry(address entry, CompiledICHolder* icholder) {
119    _entry      = entry;
120    _cached_value = (void*)icholder;
121    _to_interpreter = true;
122    _to_aot = false;
123    _is_icholder = true;
124    _is_optimized = false;
125    _release_icholder = true;
126  }
127
128  CompiledICInfo(): _entry(NULL), _cached_value(NULL), _is_icholder(false),
129                    _to_interpreter(false), _to_aot(false), _is_optimized(false), _release_icholder(false) {
130  }
131  ~CompiledICInfo() {
132    // In rare cases the info is computed but not used, so release any
133    // CompiledICHolder* that was created
134    if (_release_icholder) {
135      assert(_is_icholder, "must be");
136      CompiledICHolder* icholder = (CompiledICHolder*)_cached_value;
137      icholder->claim();
138      delete icholder;
139    }
140  }
141};
142
143class NativeCallWrapper: public ResourceObj {
144public:
145  virtual address destination() const = 0;
146  virtual address instruction_address() const = 0;
147  virtual address next_instruction_address() const = 0;
148  virtual address return_address() const = 0;
149  virtual address get_resolve_call_stub(bool is_optimized) const = 0;
150  virtual void set_destination_mt_safe(address dest) = 0;
151  virtual void set_to_interpreted(const methodHandle& method, CompiledICInfo& info) = 0;
152  virtual void verify() const = 0;
153  virtual void verify_resolve_call(address dest) const = 0;
154
155  virtual bool is_call_to_interpreted(address dest) const = 0;
156  virtual bool is_safe_for_patching() const = 0;
157
158  virtual NativeInstruction* get_load_instruction(virtual_call_Relocation* r) const = 0;
159
160  virtual void *get_data(NativeInstruction* instruction) const = 0;
161  virtual void set_data(NativeInstruction* instruction, intptr_t data) = 0;
162};
163
164class CompiledIC: public ResourceObj {
165  friend class InlineCacheBuffer;
166  friend class ICStub;
167
168 private:
169  NativeCallWrapper* _call;
170  NativeInstruction* _value;    // patchable value cell for this IC
171  bool          _is_optimized;  // an optimized virtual call (i.e., no compiled IC)
172  CompiledMethod* _method;
173
174  CompiledIC(CompiledMethod* cm, NativeCall* ic_call);
175  CompiledIC(RelocIterator* iter);
176
177  void initialize_from_iter(RelocIterator* iter);
178
179  static bool is_icholder_entry(address entry);
180
181  // low-level inline-cache manipulation. Cannot be accessed directly, since it might not be MT-safe
182  // to change an inline-cache. These changes the underlying inline-cache directly. They *newer* make
183  // changes to a transition stub.
184  void internal_set_ic_destination(address entry_point, bool is_icstub, void* cache, bool is_icholder);
185  void set_ic_destination(ICStub* stub);
186  void set_ic_destination(address entry_point) {
187    assert(_is_optimized, "use set_ic_destination_and_value instead");
188    internal_set_ic_destination(entry_point, false, NULL, false);
189  }
190  // This only for use by ICStubs where the type of the value isn't known
191  void set_ic_destination_and_value(address entry_point, void* value) {
192    internal_set_ic_destination(entry_point, false, value, is_icholder_entry(entry_point));
193  }
194  void set_ic_destination_and_value(address entry_point, Metadata* value) {
195    internal_set_ic_destination(entry_point, false, value, false);
196  }
197  void set_ic_destination_and_value(address entry_point, CompiledICHolder* value) {
198    internal_set_ic_destination(entry_point, false, value, true);
199  }
200
201  // Reads the location of the transition stub. This will fail with an assertion, if no transition stub is
202  // associated with the inline cache.
203  address stub_address() const;
204  bool is_in_transition_state() const;  // Use InlineCacheBuffer
205
206 public:
207  // conversion (machine PC to CompiledIC*)
208  friend CompiledIC* CompiledIC_before(CompiledMethod* nm, address return_addr);
209  friend CompiledIC* CompiledIC_at(CompiledMethod* nm, address call_site);
210  friend CompiledIC* CompiledIC_at(Relocation* call_site);
211  friend CompiledIC* CompiledIC_at(RelocIterator* reloc_iter);
212
213  // This is used to release CompiledICHolder*s from nmethods that
214  // are about to be freed.  The callsite might contain other stale
215  // values of other kinds so it must be careful.
216  static void cleanup_call_site(virtual_call_Relocation* call_site, const CompiledMethod* cm);
217  static bool is_icholder_call_site(virtual_call_Relocation* call_site, const CompiledMethod* cm);
218
219  // Return the cached_metadata/destination associated with this inline cache. If the cache currently points
220  // to a transition stub, it will read the values from the transition stub.
221  void* cached_value() const;
222  CompiledICHolder* cached_icholder() const {
223    assert(is_icholder_call(), "must be");
224    return (CompiledICHolder*) cached_value();
225  }
226  Metadata* cached_metadata() const {
227    assert(!is_icholder_call(), "must be");
228    return (Metadata*) cached_value();
229  }
230
231  void* get_data() const {
232    return _call->get_data(_value);
233  }
234
235  void set_data(intptr_t data) {
236    _call->set_data(_value, data);
237  }
238
239  address ic_destination() const;
240
241  bool is_optimized() const   { return _is_optimized; }
242
243  // State
244  bool is_clean() const;
245  bool is_megamorphic() const;
246  bool is_call_to_compiled() const;
247  bool is_call_to_interpreted() const;
248
249  bool is_icholder_call() const;
250
251  address end_of_call() { return  _call->return_address(); }
252
253  // MT-safe patching of inline caches. Note: Only safe to call is_xxx when holding the CompiledIC_ock
254  // so you are guaranteed that no patching takes place. The same goes for verify.
255  //
256  // Note: We do not provide any direct access to the stub code, to prevent parts of the code
257  // to manipulate the inline cache in MT-unsafe ways.
258  //
259  // They all takes a TRAP argument, since they can cause a GC if the inline-cache buffer is full.
260  //
261  void set_to_clean(bool in_use = true);
262  void set_to_monomorphic(CompiledICInfo& info);
263  void clear_ic_stub();
264
265  // Returns true if successful and false otherwise. The call can fail if memory
266  // allocation in the code cache fails.
267  bool set_to_megamorphic(CallInfo* call_info, Bytecodes::Code bytecode, TRAPS);
268
269  static void compute_monomorphic_entry(const methodHandle& method, Klass* receiver_klass,
270                                        bool is_optimized, bool static_bound, bool caller_is_nmethod,
271                                        CompiledICInfo& info, TRAPS);
272
273  // Location
274  address instruction_address() const { return _call->instruction_address(); }
275
276  // Misc
277  void print()             PRODUCT_RETURN;
278  void print_compiled_ic() PRODUCT_RETURN;
279  void verify()            PRODUCT_RETURN;
280};
281
282inline CompiledIC* CompiledIC_before(CompiledMethod* nm, address return_addr) {
283  CompiledIC* c_ic = new CompiledIC(nm, nativeCall_before(return_addr));
284  c_ic->verify();
285  return c_ic;
286}
287
288inline CompiledIC* CompiledIC_at(CompiledMethod* nm, address call_site) {
289  CompiledIC* c_ic = new CompiledIC(nm, nativeCall_at(call_site));
290  c_ic->verify();
291  return c_ic;
292}
293
294inline CompiledIC* CompiledIC_at(Relocation* call_site) {
295  assert(call_site->type() == relocInfo::virtual_call_type ||
296         call_site->type() == relocInfo::opt_virtual_call_type, "wrong reloc. info");
297  CompiledIC* c_ic = new CompiledIC(call_site->code(), nativeCall_at(call_site->addr()));
298  c_ic->verify();
299  return c_ic;
300}
301
302inline CompiledIC* CompiledIC_at(RelocIterator* reloc_iter) {
303  assert(reloc_iter->type() == relocInfo::virtual_call_type ||
304      reloc_iter->type() == relocInfo::opt_virtual_call_type, "wrong reloc. info");
305  CompiledIC* c_ic = new CompiledIC(reloc_iter);
306  c_ic->verify();
307  return c_ic;
308}
309
310//-----------------------------------------------------------------------------
311// The CompiledStaticCall represents a call to a static method in the compiled
312//
313// Transition diagram of a static call site is somewhat simpler than for an inlined cache:
314//
315//
316//           -----<----- Clean ----->-----
317//          /                             \
318//         /                               \
319//    compilled code <------------> interpreted code
320//
321//  Clean:            Calls directly to runtime method for fixup
322//  Compiled code:    Calls directly to compiled code
323//  Interpreted code: Calls to stub that set Method* reference
324//
325//
326
327class StaticCallInfo {
328 private:
329  address      _entry;          // Entrypoint
330  methodHandle _callee;         // Callee (used when calling interpreter)
331  bool         _to_interpreter; // call to interpreted method (otherwise compiled)
332  bool         _to_aot;         // call to aot method (otherwise compiled)
333
334  friend class CompiledStaticCall;
335  friend class CompiledDirectStaticCall;
336  friend class CompiledPltStaticCall;
337 public:
338  address      entry() const    { return _entry;  }
339  methodHandle callee() const   { return _callee; }
340};
341
342class CompiledStaticCall : public ResourceObj {
343 public:
344  // Code
345  static address emit_to_interp_stub(CodeBuffer &cbuf, address mark = NULL);
346  static int to_interp_stub_size();
347  static int reloc_to_interp_stub();
348  static void emit_to_aot_stub(CodeBuffer &cbuf, address mark = NULL);
349  static int to_aot_stub_size();
350  static int reloc_to_aot_stub();
351
352  // Compute entry point given a method
353  static void compute_entry(const methodHandle& m, bool caller_is_nmethod, StaticCallInfo& info);
354
355public:
356  // Clean static call (will force resolving on next use)
357  virtual address destination() const = 0;
358
359  // Clean static call (will force resolving on next use)
360  void set_to_clean();
361
362  // Set state. The entry must be the same, as computed by compute_entry.
363  // Computation and setting is split up, since the actions are separate during
364  // a OptoRuntime::resolve_xxx.
365  void set(const StaticCallInfo& info);
366
367  // State
368  bool is_clean() const;
369  bool is_call_to_compiled() const;
370  virtual bool is_call_to_interpreted() const = 0;
371
372  virtual address instruction_address() const = 0;
373protected:
374  virtual address resolve_call_stub() const = 0;
375  virtual void set_destination_mt_safe(address dest) = 0;
376#if INCLUDE_AOT
377  virtual void set_to_far(const methodHandle& callee, address entry) = 0;
378#endif
379  virtual void set_to_interpreted(const methodHandle& callee, address entry) = 0;
380  virtual const char* name() const = 0;
381
382  void set_to_compiled(address entry);
383};
384
385class CompiledDirectStaticCall : public CompiledStaticCall {
386private:
387  friend class CompiledIC;
388  friend class DirectNativeCallWrapper;
389
390  // Also used by CompiledIC
391  void set_to_interpreted(const methodHandle& callee, address entry);
392#if INCLUDE_AOT
393  void set_to_far(const methodHandle& callee, address entry);
394#endif
395  address instruction_address() const { return _call->instruction_address(); }
396  void set_destination_mt_safe(address dest) { _call->set_destination_mt_safe(dest); }
397
398  NativeCall* _call;
399
400  CompiledDirectStaticCall(NativeCall* call) : _call(call) {}
401
402 public:
403  static inline CompiledDirectStaticCall* before(address return_addr) {
404    CompiledDirectStaticCall* st = new CompiledDirectStaticCall(nativeCall_before(return_addr));
405    st->verify();
406    return st;
407  }
408
409  static inline CompiledDirectStaticCall* at(address native_call) {
410    CompiledDirectStaticCall* st = new CompiledDirectStaticCall(nativeCall_at(native_call));
411    st->verify();
412    return st;
413  }
414
415  static inline CompiledDirectStaticCall* at(Relocation* call_site) {
416    return at(call_site->addr());
417  }
418
419  // Delegation
420  address destination() const { return _call->destination(); }
421
422  // State
423  virtual bool is_call_to_interpreted() const;
424  bool is_call_to_far() const;
425
426  // Stub support
427  static address find_stub_for(address instruction, bool is_aot);
428  address find_stub(bool is_aot);
429  static void set_stub_to_clean(static_stub_Relocation* static_stub);
430
431  // Misc.
432  void print()  PRODUCT_RETURN;
433  void verify() PRODUCT_RETURN;
434
435 protected:
436  virtual address resolve_call_stub() const;
437  virtual const char* name() const { return "CompiledDirectStaticCall"; }
438};
439
440#endif // SHARE_VM_CODE_COMPILEDIC_HPP
441