Thu, 12 May 2011 15:05:22 -0700
Merge
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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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).
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23 */
25 #ifndef SHARE_VM_RUNTIME_DEOPTIMIZATION_HPP
26 #define SHARE_VM_RUNTIME_DEOPTIMIZATION_HPP
28 #include "memory/allocation.hpp"
29 #include "runtime/frame.inline.hpp"
31 class ProfileData;
32 class vframeArray;
33 class MonitorValue;
34 class ObjectValue;
36 class Deoptimization : AllStatic {
37 public:
38 // What condition caused the deoptimization?
39 enum DeoptReason {
40 Reason_many = -1, // indicates presence of several reasons
41 Reason_none = 0, // indicates absence of a relevant deopt.
42 // Next 7 reasons are recorded per bytecode in DataLayout::trap_bits
43 Reason_null_check, // saw unexpected null or zero divisor (@bci)
44 Reason_null_assert, // saw unexpected non-null or non-zero (@bci)
45 Reason_range_check, // saw unexpected array index (@bci)
46 Reason_class_check, // saw unexpected object class (@bci)
47 Reason_array_check, // saw unexpected array class (aastore @bci)
48 Reason_intrinsic, // saw unexpected operand to intrinsic (@bci)
49 Reason_bimorphic, // saw unexpected object class in bimorphic inlining (@bci)
51 Reason_unloaded, // unloaded class or constant pool entry
52 Reason_uninitialized, // bad class state (uninitialized)
53 Reason_unreached, // code is not reached, compiler
54 Reason_unhandled, // arbitrary compiler limitation
55 Reason_constraint, // arbitrary runtime constraint violated
56 Reason_div0_check, // a null_check due to division by zero
57 Reason_age, // nmethod too old; tier threshold reached
58 Reason_predicate, // compiler generated predicate failed
59 Reason_loop_limit_check, // compiler generated loop limits check failed
60 Reason_LIMIT,
61 // Note: Keep this enum in sync. with _trap_reason_name.
62 Reason_RECORDED_LIMIT = Reason_bimorphic // some are not recorded per bc
63 // Note: Reason_RECORDED_LIMIT should be < 8 to fit into 3 bits of
64 // DataLayout::trap_bits. This dependency is enforced indirectly
65 // via asserts, to avoid excessive direct header-to-header dependencies.
66 // See Deoptimization::trap_state_reason and class DataLayout.
67 };
69 // What action must be taken by the runtime?
70 enum DeoptAction {
71 Action_none, // just interpret, do not invalidate nmethod
72 Action_maybe_recompile, // recompile the nmethod; need not invalidate
73 Action_reinterpret, // invalidate the nmethod, reset IC, maybe recompile
74 Action_make_not_entrant, // invalidate the nmethod, recompile (probably)
75 Action_make_not_compilable, // invalidate the nmethod and do not compile
76 Action_LIMIT
77 // Note: Keep this enum in sync. with _trap_action_name.
78 };
80 enum {
81 _action_bits = 3,
82 _reason_bits = 5,
83 _action_shift = 0,
84 _reason_shift = _action_shift+_action_bits,
85 BC_CASE_LIMIT = PRODUCT_ONLY(1) NOT_PRODUCT(4) // for _deoptimization_hist
86 };
88 enum UnpackType {
89 Unpack_deopt = 0, // normal deoptimization, use pc computed in unpack_vframe_on_stack
90 Unpack_exception = 1, // exception is pending
91 Unpack_uncommon_trap = 2, // redo last byte code (C2 only)
92 Unpack_reexecute = 3 // reexecute bytecode (C1 only)
93 };
95 // Checks all compiled methods. Invalid methods are deleted and
96 // corresponding activations are deoptimized.
97 static int deoptimize_dependents();
99 // Deoptimizes a frame lazily. nmethod gets patched deopt happens on return to the frame
100 static void deoptimize(JavaThread* thread, frame fr, RegisterMap *reg_map);
102 private:
103 // Does the actual work for deoptimizing a single frame
104 static void deoptimize_single_frame(JavaThread* thread, frame fr);
106 // Helper function to revoke biases of all monitors in frame if UseBiasedLocking
107 // is enabled
108 static void revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map);
109 // Helper function to revoke biases of all monitors in frames
110 // executing in a particular CodeBlob if UseBiasedLocking is enabled
111 static void revoke_biases_of_monitors(CodeBlob* cb);
113 #ifdef COMPILER2
114 // Support for restoring non-escaping objects
115 static bool realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS);
116 static void reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type);
117 static void reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj);
118 static void reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects);
119 static void relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread);
120 NOT_PRODUCT(static void print_objects(GrowableArray<ScopeValue*>* objects);)
121 #endif // COMPILER2
123 public:
124 static vframeArray* create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk);
126 // Interface used for unpacking deoptimized frames
128 // UnrollBlock is returned by fetch_unroll_info() to the deoptimization handler (blob).
129 // This is only a CheapObj to ease debugging after a deopt failure
130 class UnrollBlock : public CHeapObj {
131 private:
132 int _size_of_deoptimized_frame; // Size, in bytes, of current deoptimized frame
133 int _caller_adjustment; // Adjustment, in bytes, to caller's SP by initial interpreted frame
134 int _number_of_frames; // Number frames to unroll
135 int _total_frame_sizes; // Total of number*sizes frames
136 intptr_t* _frame_sizes; // Array of frame sizes, in bytes, for unrolling the stack
137 address* _frame_pcs; // Array of frame pc's, in bytes, for unrolling the stack
138 intptr_t* _register_block; // Block for storing callee-saved registers.
139 BasicType _return_type; // Tells if we have to restore double or long return value
140 intptr_t _initial_fp; // FP of the sender frame
141 // The following fields are used as temps during the unpacking phase
142 // (which is tight on registers, especially on x86). They really ought
143 // to be PD variables but that involves moving this class into its own
144 // file to use the pd include mechanism. Maybe in a later cleanup ...
145 intptr_t _counter_temp; // SHOULD BE PD VARIABLE (x86 frame count temp)
146 intptr_t _unpack_kind; // SHOULD BE PD VARIABLE (x86 unpack kind)
147 intptr_t _sender_sp_temp; // SHOULD BE PD VARIABLE (x86 sender_sp)
148 public:
149 // Constructor
150 UnrollBlock(int size_of_deoptimized_frame,
151 int caller_adjustment,
152 int number_of_frames,
153 intptr_t* frame_sizes,
154 address* frames_pcs,
155 BasicType return_type);
156 ~UnrollBlock();
158 // Returns where a register is located.
159 intptr_t* value_addr_at(int register_number) const;
161 // Accessors
162 intptr_t* frame_sizes() const { return _frame_sizes; }
163 int number_of_frames() const { return _number_of_frames; }
164 address* frame_pcs() const { return _frame_pcs ; }
166 // Returns the total size of frames
167 int size_of_frames() const;
169 void set_initial_fp(intptr_t fp) { _initial_fp = fp; }
171 // Accessors used by the code generator for the unpack stub.
172 static int size_of_deoptimized_frame_offset_in_bytes() { return offset_of(UnrollBlock, _size_of_deoptimized_frame); }
173 static int caller_adjustment_offset_in_bytes() { return offset_of(UnrollBlock, _caller_adjustment); }
174 static int number_of_frames_offset_in_bytes() { return offset_of(UnrollBlock, _number_of_frames); }
175 static int frame_sizes_offset_in_bytes() { return offset_of(UnrollBlock, _frame_sizes); }
176 static int total_frame_sizes_offset_in_bytes() { return offset_of(UnrollBlock, _total_frame_sizes); }
177 static int frame_pcs_offset_in_bytes() { return offset_of(UnrollBlock, _frame_pcs); }
178 static int register_block_offset_in_bytes() { return offset_of(UnrollBlock, _register_block); }
179 static int return_type_offset_in_bytes() { return offset_of(UnrollBlock, _return_type); }
180 static int counter_temp_offset_in_bytes() { return offset_of(UnrollBlock, _counter_temp); }
181 static int initial_fp_offset_in_bytes() { return offset_of(UnrollBlock, _initial_fp); }
182 static int unpack_kind_offset_in_bytes() { return offset_of(UnrollBlock, _unpack_kind); }
183 static int sender_sp_temp_offset_in_bytes() { return offset_of(UnrollBlock, _sender_sp_temp); }
185 BasicType return_type() const { return _return_type; }
186 void print();
187 };
189 //** Returns an UnrollBlock continuing information
190 // how to make room for the resulting interpreter frames.
191 // Called by assembly stub after execution has returned to
192 // deoptimized frame.
193 // @argument thread. Thread where stub_frame resides.
194 // @see OptoRuntime::deoptimization_fetch_unroll_info_C
195 static UnrollBlock* fetch_unroll_info(JavaThread* thread);
197 //** Unpacks vframeArray onto execution stack
198 // Called by assembly stub after execution has returned to
199 // deoptimized frame and after the stack unrolling.
200 // @argument thread. Thread where stub_frame resides.
201 // @argument exec_mode. Determines how execution should be continuted in top frame.
202 // 0 means continue after current byte code
203 // 1 means exception has happened, handle exception
204 // 2 means reexecute current bytecode (for uncommon traps).
205 // @see OptoRuntime::deoptimization_unpack_frames_C
206 // Return BasicType of call return type, if any
207 static BasicType unpack_frames(JavaThread* thread, int exec_mode);
209 // Cleans up deoptimization bits on thread after unpacking or in the
210 // case of an exception.
211 static void cleanup_deopt_info(JavaThread *thread,
212 vframeArray * array);
214 // Restores callee saved values from deoptimized frame into oldest interpreter frame
215 // so caller of the deoptimized frame will get back the values it expects.
216 static void unwind_callee_save_values(frame* f, vframeArray* vframe_array);
218 //** Performs an uncommon trap for compiled code.
219 // The top most compiler frame is converted into interpreter frames
220 static UnrollBlock* uncommon_trap(JavaThread* thread, jint unloaded_class_index);
221 // Helper routine that enters the VM and may block
222 static void uncommon_trap_inner(JavaThread* thread, jint unloaded_class_index);
224 //** Deoptimizes the frame identified by id.
225 // Only called from VMDeoptimizeFrame
226 // @argument thread. Thread where stub_frame resides.
227 // @argument id. id of frame that should be deoptimized.
228 static void deoptimize_frame_internal(JavaThread* thread, intptr_t* id);
230 // If thread is not the current thread then execute
231 // VM_DeoptimizeFrame otherwise deoptimize directly.
232 static void deoptimize_frame(JavaThread* thread, intptr_t* id);
234 // Statistics
235 static void gather_statistics(DeoptReason reason, DeoptAction action,
236 Bytecodes::Code bc = Bytecodes::_illegal);
237 static void print_statistics();
239 // How much room to adjust the last frame's SP by, to make space for
240 // the callee's interpreter frame (which expects locals to be next to
241 // incoming arguments)
242 static int last_frame_adjust(int callee_parameters, int callee_locals);
244 // trap_request codes
245 static DeoptReason trap_request_reason(int trap_request) {
246 if (trap_request < 0)
247 return (DeoptReason)
248 ((~(trap_request) >> _reason_shift) & right_n_bits(_reason_bits));
249 else
250 // standard reason for unloaded CP entry
251 return Reason_unloaded;
252 }
253 static DeoptAction trap_request_action(int trap_request) {
254 if (trap_request < 0)
255 return (DeoptAction)
256 ((~(trap_request) >> _action_shift) & right_n_bits(_action_bits));
257 else
258 // standard action for unloaded CP entry
259 return _unloaded_action;
260 }
261 static int trap_request_index(int trap_request) {
262 if (trap_request < 0)
263 return -1;
264 else
265 return trap_request;
266 }
267 static int make_trap_request(DeoptReason reason, DeoptAction action,
268 int index = -1) {
269 assert((1 << _reason_bits) >= Reason_LIMIT, "enough bits");
270 assert((1 << _action_bits) >= Action_LIMIT, "enough bits");
271 int trap_request;
272 if (index != -1)
273 trap_request = index;
274 else
275 trap_request = (~(((reason) << _reason_shift)
276 + ((action) << _action_shift)));
277 assert(reason == trap_request_reason(trap_request), "valid reason");
278 assert(action == trap_request_action(trap_request), "valid action");
279 assert(index == trap_request_index(trap_request), "valid index");
280 return trap_request;
281 }
283 // The trap_state stored in a MDO is decoded here.
284 // It records two items of information.
285 // reason: If a deoptimization happened here, what its reason was,
286 // or if there were multiple deopts with differing reasons.
287 // recompiled: If a deoptimization here triggered a recompilation.
288 // Note that not all reasons are recorded per-bci.
289 static DeoptReason trap_state_reason(int trap_state);
290 static int trap_state_has_reason(int trap_state, int reason);
291 static int trap_state_add_reason(int trap_state, int reason);
292 static bool trap_state_is_recompiled(int trap_state);
293 static int trap_state_set_recompiled(int trap_state, bool z);
294 static const char* format_trap_state(char* buf, size_t buflen,
295 int trap_state);
297 static bool reason_is_recorded_per_bytecode(DeoptReason reason) {
298 return reason > Reason_none && reason <= Reason_RECORDED_LIMIT;
299 }
301 static DeoptReason reason_recorded_per_bytecode_if_any(DeoptReason reason) {
302 if (reason_is_recorded_per_bytecode(reason))
303 return reason;
304 else if (reason == Reason_div0_check) // null check due to divide-by-zero?
305 return Reason_null_check; // recorded per BCI as a null check
306 else
307 return Reason_none;
308 }
310 static const char* trap_reason_name(int reason);
311 static const char* trap_action_name(int action);
312 // Format like reason='foo' action='bar' index='123'.
313 // This is suitable both for XML and for tty output.
314 static const char* format_trap_request(char* buf, size_t buflen,
315 int trap_request);
317 static jint total_deoptimization_count();
318 static jint deoptimization_count(DeoptReason reason);
320 // JVMTI PopFrame support
322 // Preserves incoming arguments to the popped frame when it is
323 // returning to a deoptimized caller
324 static void popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address);
326 private:
327 static methodDataOop get_method_data(JavaThread* thread, methodHandle m, bool create_if_missing);
328 // Update the mdo's count and per-BCI reason bits, returning previous state:
329 static ProfileData* query_update_method_data(methodDataHandle trap_mdo,
330 int trap_bci,
331 DeoptReason reason,
332 //outputs:
333 uint& ret_this_trap_count,
334 bool& ret_maybe_prior_trap,
335 bool& ret_maybe_prior_recompile);
336 // class loading support for uncommon trap
337 static void load_class_by_index(constantPoolHandle constant_pool, int index, TRAPS);
338 static void load_class_by_index(constantPoolHandle constant_pool, int index);
340 static UnrollBlock* fetch_unroll_info_helper(JavaThread* thread);
342 static DeoptAction _unloaded_action; // == Action_reinterpret;
343 static const char* _trap_reason_name[Reason_LIMIT];
344 static const char* _trap_action_name[Action_LIMIT];
346 static juint _deoptimization_hist[Reason_LIMIT][1+Action_LIMIT][BC_CASE_LIMIT];
347 // Note: Histogram array size is 1-2 Kb.
349 public:
350 static void update_method_data_from_interpreter(methodDataHandle trap_mdo, int trap_bci, int reason);
351 };
353 class DeoptimizationMarker : StackObj { // for profiling
354 static bool _is_active;
355 public:
356 DeoptimizationMarker() { _is_active = true; }
357 ~DeoptimizationMarker() { _is_active = false; }
358 static bool is_active() { return _is_active; }
359 };
361 #endif // SHARE_VM_RUNTIME_DEOPTIMIZATION_HPP