1 /*
2 * Copyright (c) 1997, 2013, 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
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 "interpreter/linkResolver.hpp"
29 #include "oops/compiledICHolder.hpp"
30 #ifdef TARGET_ARCH_x86
31 # include "nativeInst_x86.hpp"
32 #endif
33 #ifdef TARGET_ARCH_sparc
34 # include "nativeInst_sparc.hpp"
35 #endif
36 #ifdef TARGET_ARCH_zero
37 # include "nativeInst_zero.hpp"
38 #endif
39 #ifdef TARGET_ARCH_arm
40 # include "nativeInst_arm.hpp"
41 #endif
42 #ifdef TARGET_ARCH_ppc
43 # include "nativeInst_ppc.hpp"
44 #endif
45
46 //-----------------------------------------------------------------------------
47 // The CompiledIC represents a compiled inline cache.
48 //
49 // In order to make patching of the inline cache MT-safe, we only allow the following
50 // transitions (when not at a safepoint):
51 //
52 //
53 // [1] --<-- Clean -->--- [1]
54 // / (null) \
55 // / \ /-<-\
56 // / [2] \ / \
57 // Interpreted ---------> Monomorphic | [3]
58 // (CompiledICHolder*) (Klass*) |
59 // \ / \ /
60 // [4] \ / [4] \->-/
61 // \->- Megamorphic -<-/
62 // (Method*)
63 //
64 // The text in paranteses () refere to the value of the inline cache receiver (mov instruction)
65 //
66 // The numbers in square brackets refere to the kind of transition:
67 // [1]: Initial fixup. Receiver it found from debug information
68 // [2]: Compilation of a method
69 // [3]: Recompilation of a method (note: only entry is changed. The Klass* must stay the same)
70 // [4]: Inline cache miss. We go directly to megamorphic call.
71 //
72 // The class automatically inserts transition stubs (using the InlineCacheBuffer) when an MT-unsafe
73 // transition is made to a stub.
74 //
75 class CompiledIC;
76 class ICStub;
77
78 class CompiledICInfo : public StackObj {
79 private:
80 address _entry; // entry point for call
81 void* _cached_value; // Value of cached_value (either in stub or inline cache)
82 bool _is_icholder; // Is the cached value a CompiledICHolder*
83 bool _is_optimized; // it is an optimized virtual call (i.e., can be statically bound)
84 bool _to_interpreter; // Call it to interpreter
85 bool _release_icholder;
86 public:
87 address entry() const { return _entry; }
88 Metadata* cached_metadata() const { assert(!_is_icholder, ""); return (Metadata*)_cached_value; }
89 CompiledICHolder* claim_cached_icholder() {
90 assert(_is_icholder, "");
91 assert(_cached_value != NULL, "must be non-NULL");
92 _release_icholder = false;
93 CompiledICHolder* icholder = (CompiledICHolder*)_cached_value;
94 icholder->claim();
95 return icholder;
96 }
97 bool is_optimized() const { return _is_optimized; }
98 bool to_interpreter() const { return _to_interpreter; }
99
100 void set_compiled_entry(address entry, Klass* klass, bool is_optimized) {
101 _entry = entry;
102 _cached_value = (void*)klass;
103 _to_interpreter = false;
104 _is_icholder = false;
105 _is_optimized = is_optimized;
106 _release_icholder = false;
107 }
108
109 void set_interpreter_entry(address entry, Method* method) {
110 _entry = entry;
111 _cached_value = (void*)method;
112 _to_interpreter = 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 _is_icholder = true;
123 _is_optimized = false;
124 _release_icholder = true;
125 }
126
127 CompiledICInfo(): _entry(NULL), _cached_value(NULL), _is_icholder(false),
128 _to_interpreter(false), _is_optimized(false), _release_icholder(false) {
129 }
130 ~CompiledICInfo() {
131 // In rare cases the info is computed but not used, so release any
132 // CompiledICHolder* that was created
133 if (_release_icholder) {
134 assert(_is_icholder, "must be");
135 CompiledICHolder* icholder = (CompiledICHolder*)_cached_value;
136 icholder->claim();
137 delete icholder;
138 }
139 }
140 };
141
142 class CompiledIC: public ResourceObj {
143 friend class InlineCacheBuffer;
144 friend class ICStub;
145
146
147 private:
148 NativeCall* _ic_call; // the call instruction
149 NativeMovConstReg* _value; // patchable value cell for this IC
150 bool _is_optimized; // an optimized virtual call (i.e., no compiled IC)
151
152 CompiledIC(nmethod* nm, NativeCall* ic_call);
153 CompiledIC(RelocIterator* iter);
154
155 void initialize_from_iter(RelocIterator* iter);
156
157 static bool is_icholder_entry(address entry);
158
159 // low-level inline-cache manipulation. Cannot be accessed directly, since it might not be MT-safe
160 // to change an inline-cache. These changes the underlying inline-cache directly. They *newer* make
161 // changes to a transition stub.
162 void internal_set_ic_destination(address entry_point, bool is_icstub, void* cache, bool is_icholder);
163 void set_ic_destination(ICStub* stub);
164 void set_ic_destination(address entry_point) {
165 assert(_is_optimized, "use set_ic_destination_and_value instead");
166 internal_set_ic_destination(entry_point, false, NULL, false);
167 }
168 // This only for use by ICStubs where the type of the value isn't known
169 void set_ic_destination_and_value(address entry_point, void* value) {
170 internal_set_ic_destination(entry_point, false, value, is_icholder_entry(entry_point));
171 }
172 void set_ic_destination_and_value(address entry_point, Metadata* value) {
173 internal_set_ic_destination(entry_point, false, value, false);
174 }
175 void set_ic_destination_and_value(address entry_point, CompiledICHolder* value) {
176 internal_set_ic_destination(entry_point, false, value, true);
177 }
178
179 // Reads the location of the transition stub. This will fail with an assertion, if no transition stub is
180 // associated with the inline cache.
181 address stub_address() const;
182 bool is_in_transition_state() const; // Use InlineCacheBuffer
183
184 public:
185 // conversion (machine PC to CompiledIC*)
186 friend CompiledIC* CompiledIC_before(nmethod* nm, address return_addr);
187 friend CompiledIC* CompiledIC_at(nmethod* nm, address call_site);
188 friend CompiledIC* CompiledIC_at(Relocation* call_site);
189 friend CompiledIC* CompiledIC_at(RelocIterator* reloc_iter);
190
191 // This is used to release CompiledICHolder*s from nmethods that
192 // are about to be freed. The callsite might contain other stale
193 // values of other kinds so it must be careful.
194 static void cleanup_call_site(virtual_call_Relocation* call_site);
195 static bool is_icholder_call_site(virtual_call_Relocation* call_site);
196
197 // Return the cached_metadata/destination associated with this inline cache. If the cache currently points
198 // to a transition stub, it will read the values from the transition stub.
199 void* cached_value() const;
200 CompiledICHolder* cached_icholder() const {
201 assert(is_icholder_call(), "must be");
202 return (CompiledICHolder*) cached_value();
203 }
204 Metadata* cached_metadata() const {
205 assert(!is_icholder_call(), "must be");
206 return (Metadata*) cached_value();
207 }
208
209 address ic_destination() const;
210
211 bool is_optimized() const { return _is_optimized; }
212
213 // State
214 bool is_clean() const;
215 bool is_megamorphic() const;
216 bool is_call_to_compiled() const;
217 bool is_call_to_interpreted() const;
218
219 bool is_icholder_call() const;
220
221 address end_of_call() { return _ic_call->return_address(); }
222
223 // MT-safe patching of inline caches. Note: Only safe to call is_xxx when holding the CompiledIC_ock
224 // so you are guaranteed that no patching takes place. The same goes for verify.
225 //
226 // Note: We do not provide any direct access to the stub code, to prevent parts of the code
227 // to manipulate the inline cache in MT-unsafe ways.
228 //
229 // They all takes a TRAP argument, since they can cause a GC if the inline-cache buffer is full.
230 //
231 void set_to_clean(bool in_use = true);
232 void set_to_monomorphic(CompiledICInfo& info);
233 void clear_ic_stub();
234
235 // Returns true if successful and false otherwise. The call can fail if memory
236 // allocation in the code cache fails.
237 bool set_to_megamorphic(CallInfo* call_info, Bytecodes::Code bytecode, TRAPS);
238
239 static void compute_monomorphic_entry(methodHandle method, KlassHandle receiver_klass,
240 bool is_optimized, bool static_bound, CompiledICInfo& info, TRAPS);
241
242 // Location
243 address instruction_address() const { return _ic_call->instruction_address(); }
244
245 // Misc
246 void print() PRODUCT_RETURN;
247 void print_compiled_ic() PRODUCT_RETURN;
248 void verify() PRODUCT_RETURN;
249 };
250
251 inline CompiledIC* CompiledIC_before(nmethod* nm, address return_addr) {
252 CompiledIC* c_ic = new CompiledIC(nm, nativeCall_before(return_addr));
253 c_ic->verify();
254 return c_ic;
255 }
256
257 inline CompiledIC* CompiledIC_at(nmethod* nm, address call_site) {
258 CompiledIC* c_ic = new CompiledIC(nm, nativeCall_at(call_site));
259 c_ic->verify();
260 return c_ic;
261 }
262
263 inline CompiledIC* CompiledIC_at(Relocation* call_site) {
264 assert(call_site->type() == relocInfo::virtual_call_type ||
265 call_site->type() == relocInfo::opt_virtual_call_type, "wrong reloc. info");
266 CompiledIC* c_ic = new CompiledIC(call_site->code(), nativeCall_at(call_site->addr()));
267 c_ic->verify();
268 return c_ic;
269 }
270
271 inline CompiledIC* CompiledIC_at(RelocIterator* reloc_iter) {
272 assert(reloc_iter->type() == relocInfo::virtual_call_type ||
273 reloc_iter->type() == relocInfo::opt_virtual_call_type, "wrong reloc. info");
274 CompiledIC* c_ic = new CompiledIC(reloc_iter);
275 c_ic->verify();
276 return c_ic;
277 }
278
279 //-----------------------------------------------------------------------------
280 // The CompiledStaticCall represents a call to a static method in the compiled
281 //
282 // Transition diagram of a static call site is somewhat simpler than for an inlined cache:
283 //
284 //
285 // -----<----- Clean ----->-----
286 // / \
287 // / \
288 // compilled code <------------> interpreted code
289 //
290 // Clean: Calls directly to runtime method for fixup
291 // Compiled code: Calls directly to compiled code
292 // Interpreted code: Calls to stub that set Method* reference
293 //
294 //
295 class CompiledStaticCall;
296
297 class StaticCallInfo {
298 private:
299 address _entry; // Entrypoint
300 methodHandle _callee; // Callee (used when calling interpreter)
301 bool _to_interpreter; // call to interpreted method (otherwise compiled)
302
303 friend class CompiledStaticCall;
304 public:
305 address entry() const { return _entry; }
306 methodHandle callee() const { return _callee; }
307 };
308
309
310 class CompiledStaticCall: public NativeCall {
311 friend class CompiledIC;
312
313 // Also used by CompiledIC
314 void set_to_interpreted(methodHandle callee, address entry);
315 bool is_optimized_virtual();
316
317 public:
318 friend CompiledStaticCall* compiledStaticCall_before(address return_addr);
319 friend CompiledStaticCall* compiledStaticCall_at(address native_call);
320 friend CompiledStaticCall* compiledStaticCall_at(Relocation* call_site);
321
322 // Code
323 static address emit_to_interp_stub(CodeBuffer &cbuf);
324 static int to_interp_stub_size();
325 static int reloc_to_interp_stub();
326
327 // State
328 bool is_clean() const;
329 bool is_call_to_compiled() const;
330 bool is_call_to_interpreted() const;
331
332 // Clean static call (will force resolving on next use)
333 void set_to_clean();
334
335 // Set state. The entry must be the same, as computed by compute_entry.
336 // Computation and setting is split up, since the actions are separate during
337 // a OptoRuntime::resolve_xxx.
338 void set(const StaticCallInfo& info);
339
340 // Compute entry point given a method
341 static void compute_entry(methodHandle m, StaticCallInfo& info);
342
343 // Stub support
344 address find_stub();
345 static void set_stub_to_clean(static_stub_Relocation* static_stub);
346
347 // Misc.
348 void print() PRODUCT_RETURN;
349 void verify() PRODUCT_RETURN;
350 };
351
352
353 inline CompiledStaticCall* compiledStaticCall_before(address return_addr) {
354 CompiledStaticCall* st = (CompiledStaticCall*)nativeCall_before(return_addr);
355 st->verify();
356 return st;
357 }
358
359 inline CompiledStaticCall* compiledStaticCall_at(address native_call) {
360 CompiledStaticCall* st = (CompiledStaticCall*)native_call;
361 st->verify();
362 return st;
363 }
364
365 inline CompiledStaticCall* compiledStaticCall_at(Relocation* call_site) {
366 return compiledStaticCall_at(call_site->addr());
367 }
368
369 #endif // SHARE_VM_CODE_COMPILEDIC_HPP