compiledIC.hpp revision 1472:c18cbe5936b8 
1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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7 * published by the Free Software Foundation.
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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
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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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23 */
24
25//-----------------------------------------------------------------------------
26// The CompiledIC represents a compiled inline cache.
27//
28// In order to make patching of the inline cache MT-safe, we only allow the following
29// transitions (when not at a safepoint):
30//
31//
32//         [1] --<--  Clean -->---  [1]
33//            /       (null)      \
34//           /                     \      /-<-\
35//          /          [2]          \    /     \
36//      Interpreted  ---------> Monomorphic     | [3]
37//  (compiledICHolderOop)        (klassOop)     |
38//          \                        /   \     /
39//       [4] \                      / [4] \->-/
40//            \->-  Megamorphic -<-/
41//                  (methodOop)
42//
43// The text in paranteses () refere to the value of the inline cache receiver (mov instruction)
44//
45// The numbers in square brackets refere to the kind of transition:
46// [1]: Initial fixup. Receiver it found from debug information
47// [2]: Compilation of a method
48// [3]: Recompilation of a method (note: only entry is changed. The klassOop must stay the same)
49// [4]: Inline cache miss. We go directly to megamorphic call.
50//
51// The class automatically inserts transition stubs (using the InlineCacheBuffer) when an MT-unsafe
52// transition is made to a stub.
53//
54class CompiledIC;
55
56class CompiledICInfo {
57  friend class CompiledIC;
58 private:
59  address _entry;              // entry point for call
60  Handle  _cached_oop;         // Value of cached_oop (either in stub or inline cache)
61  bool    _is_optimized;       // it is an optimized virtual call (i.e., can be statically bound)
62  bool    _to_interpreter;     // Call it to interpreter
63 public:
64  address entry() const        { return _entry; }
65  Handle  cached_oop() const   { return _cached_oop; }
66  bool    is_optimized() const { return _is_optimized; }
67};
68
69class CompiledIC: public ResourceObj {
70  friend class InlineCacheBuffer;
71  friend class ICStub;
72
73
74 private:
75  NativeCall*   _ic_call;       // the call instruction
76  oop*          _oop_addr;      // patchable oop cell for this IC
77  RelocIterator _oops;          // iteration over any and all set-oop instructions
78  bool          _is_optimized;  // an optimized virtual call (i.e., no compiled IC)
79
80  CompiledIC(NativeCall* ic_call);
81  CompiledIC(Relocation* ic_reloc);    // Must be of virtual_call_type/opt_virtual_call_type
82
83  // low-level inline-cache manipulation. Cannot be accessed directly, since it might not be MT-safe
84  // to change an inline-cache. These changes the underlying inline-cache directly. They *newer* make
85  // changes to a transition stub.
86  void set_ic_destination(address entry_point);
87  void set_cached_oop(oop cache);
88
89  // Reads the location of the transition stub. This will fail with an assertion, if no transition stub is
90  // associated with the inline cache.
91  address stub_address() const;
92  bool is_in_transition_state() const;  // Use InlineCacheBuffer
93
94 public:
95  // conversion (machine PC to CompiledIC*)
96  friend CompiledIC* CompiledIC_before(address return_addr);
97  friend CompiledIC* CompiledIC_at(address call_site);
98  friend CompiledIC* CompiledIC_at(Relocation* call_site);
99
100  // Return the cached_oop/destination associated with this inline cache. If the cache currently points
101  // to a transition stub, it will read the values from the transition stub.
102  oop  cached_oop() const;
103  address ic_destination() const;
104
105  bool is_optimized() const   { return _is_optimized; }
106
107  // State
108  bool is_clean() const;
109  bool is_megamorphic() const;
110  bool is_call_to_compiled() const;
111  bool is_call_to_interpreted() const;
112
113  address end_of_call() { return  _ic_call->return_address(); }
114
115  // MT-safe patching of inline caches. Note: Only safe to call is_xxx when holding the CompiledIC_ock
116  // so you are guaranteed that no patching takes place. The same goes for verify.
117  //
118  // Note: We do not provide any direct access to the stub code, to prevent parts of the code
119  // to manipulate the inline cache in MT-unsafe ways.
120  //
121  // They all takes a TRAP argument, since they can cause a GC if the inline-cache buffer is full.
122  //
123  void set_to_clean();  // Can only be called during a safepoint operation
124  void set_to_monomorphic(const CompiledICInfo& info);
125  void set_to_megamorphic(CallInfo* call_info, Bytecodes::Code bytecode, TRAPS);
126
127  static void compute_monomorphic_entry(methodHandle method, KlassHandle receiver_klass,
128                                        bool is_optimized, bool static_bound, CompiledICInfo& info, TRAPS);
129
130  // Location
131  address instruction_address() const { return _ic_call->instruction_address(); }
132
133  // Misc
134  void print()             PRODUCT_RETURN;
135  void print_compiled_ic() PRODUCT_RETURN;
136  void verify()            PRODUCT_RETURN;
137};
138
139inline CompiledIC* CompiledIC_before(address return_addr) {
140  CompiledIC* c_ic = new CompiledIC(nativeCall_before(return_addr));
141  c_ic->verify();
142  return c_ic;
143}
144
145inline CompiledIC* CompiledIC_at(address call_site) {
146  CompiledIC* c_ic = new CompiledIC(nativeCall_at(call_site));
147  c_ic->verify();
148  return c_ic;
149}
150
151inline CompiledIC* CompiledIC_at(Relocation* call_site) {
152  CompiledIC* c_ic = new CompiledIC(call_site);
153  c_ic->verify();
154  return c_ic;
155}
156
157
158//-----------------------------------------------------------------------------
159// The CompiledStaticCall represents a call to a static method in the compiled
160//
161// Transition diagram of a static call site is somewhat simpler than for an inlined cache:
162//
163//
164//           -----<----- Clean ----->-----
165//          /                             \
166//         /                               \
167//    compilled code <------------> interpreted code
168//
169//  Clean:            Calls directly to runtime method for fixup
170//  Compiled code:    Calls directly to compiled code
171//  Interpreted code: Calls to stub that set methodOop reference
172//
173//
174class CompiledStaticCall;
175
176class StaticCallInfo {
177 private:
178  address      _entry;          // Entrypoint
179  methodHandle _callee;         // Callee (used when calling interpreter)
180  bool         _to_interpreter; // call to interpreted method (otherwise compiled)
181
182  friend class CompiledStaticCall;
183 public:
184  address      entry() const    { return _entry;  }
185  methodHandle callee() const   { return _callee; }
186};
187
188
189class CompiledStaticCall: public NativeCall {
190  friend class CompiledIC;
191
192  // Also used by CompiledIC
193  void set_to_interpreted(methodHandle callee, address entry);
194  bool is_optimized_virtual();
195
196 public:
197  friend CompiledStaticCall* compiledStaticCall_before(address return_addr);
198  friend CompiledStaticCall* compiledStaticCall_at(address native_call);
199  friend CompiledStaticCall* compiledStaticCall_at(Relocation* call_site);
200
201  // State
202  bool is_clean() const;
203  bool is_call_to_compiled() const;
204  bool is_call_to_interpreted() const;
205
206  // Clean static call (will force resolving on next use)
207  void set_to_clean();
208
209  // Set state. The entry must be the same, as computed by compute_entry.
210  // Computation and setting is split up, since the actions are separate during
211  // a OptoRuntime::resolve_xxx.
212  void set(const StaticCallInfo& info);
213
214  // Compute entry point given a method
215  static void compute_entry(methodHandle m, StaticCallInfo& info);
216
217  // Stub support
218  address find_stub();
219  static void set_stub_to_clean(static_stub_Relocation* static_stub);
220
221  // Misc.
222  void print()  PRODUCT_RETURN;
223  void verify() PRODUCT_RETURN;
224};
225
226
227inline CompiledStaticCall* compiledStaticCall_before(address return_addr) {
228  CompiledStaticCall* st = (CompiledStaticCall*)nativeCall_before(return_addr);
229  st->verify();
230  return st;
231}
232
233inline CompiledStaticCall* compiledStaticCall_at(address native_call) {
234  CompiledStaticCall* st = (CompiledStaticCall*)native_call;
235  st->verify();
236  return st;
237}
238
239inline CompiledStaticCall* compiledStaticCall_at(Relocation* call_site) {
240  return compiledStaticCall_at(call_site->addr());
241}
242