1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/runtime/deoptimization.hpp Wed Apr 27 01:25:04 2016 +0800
1.3 @@ -0,0 +1,385 @@
1.4 +/*
1.5 + * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#ifndef SHARE_VM_RUNTIME_DEOPTIMIZATION_HPP
1.29 +#define SHARE_VM_RUNTIME_DEOPTIMIZATION_HPP
1.30 +
1.31 +#include "memory/allocation.hpp"
1.32 +#include "runtime/frame.inline.hpp"
1.33 +
1.34 +class ProfileData;
1.35 +class vframeArray;
1.36 +class MonitorValue;
1.37 +class ObjectValue;
1.38 +
1.39 +class Deoptimization : AllStatic {
1.40 + friend class VMStructs;
1.41 +
1.42 + public:
1.43 + // What condition caused the deoptimization?
1.44 + enum DeoptReason {
1.45 + Reason_many = -1, // indicates presence of several reasons
1.46 + Reason_none = 0, // indicates absence of a relevant deopt.
1.47 + // Next 7 reasons are recorded per bytecode in DataLayout::trap_bits
1.48 + Reason_null_check, // saw unexpected null or zero divisor (@bci)
1.49 + Reason_null_assert, // saw unexpected non-null or non-zero (@bci)
1.50 + Reason_range_check, // saw unexpected array index (@bci)
1.51 + Reason_class_check, // saw unexpected object class (@bci)
1.52 + Reason_array_check, // saw unexpected array class (aastore @bci)
1.53 + Reason_intrinsic, // saw unexpected operand to intrinsic (@bci)
1.54 + Reason_bimorphic, // saw unexpected object class in bimorphic inlining (@bci)
1.55 +
1.56 + Reason_unloaded, // unloaded class or constant pool entry
1.57 + Reason_uninitialized, // bad class state (uninitialized)
1.58 + Reason_unreached, // code is not reached, compiler
1.59 + Reason_unhandled, // arbitrary compiler limitation
1.60 + Reason_constraint, // arbitrary runtime constraint violated
1.61 + Reason_div0_check, // a null_check due to division by zero
1.62 + Reason_age, // nmethod too old; tier threshold reached
1.63 + Reason_predicate, // compiler generated predicate failed
1.64 + Reason_loop_limit_check, // compiler generated loop limits check failed
1.65 + Reason_speculate_class_check, // saw unexpected object class from type speculation
1.66 + Reason_rtm_state_change, // rtm state change detected
1.67 + Reason_LIMIT,
1.68 + // Note: Keep this enum in sync. with _trap_reason_name.
1.69 + Reason_RECORDED_LIMIT = Reason_bimorphic // some are not recorded per bc
1.70 + // Note: Reason_RECORDED_LIMIT should be < 8 to fit into 3 bits of
1.71 + // DataLayout::trap_bits. This dependency is enforced indirectly
1.72 + // via asserts, to avoid excessive direct header-to-header dependencies.
1.73 + // See Deoptimization::trap_state_reason and class DataLayout.
1.74 + };
1.75 +
1.76 + // What action must be taken by the runtime?
1.77 + enum DeoptAction {
1.78 + Action_none, // just interpret, do not invalidate nmethod
1.79 + Action_maybe_recompile, // recompile the nmethod; need not invalidate
1.80 + Action_reinterpret, // invalidate the nmethod, reset IC, maybe recompile
1.81 + Action_make_not_entrant, // invalidate the nmethod, recompile (probably)
1.82 + Action_make_not_compilable, // invalidate the nmethod and do not compile
1.83 + Action_LIMIT
1.84 + // Note: Keep this enum in sync. with _trap_action_name.
1.85 + };
1.86 +
1.87 + enum {
1.88 + _action_bits = 3,
1.89 + _reason_bits = 5,
1.90 + _action_shift = 0,
1.91 + _reason_shift = _action_shift+_action_bits,
1.92 + BC_CASE_LIMIT = PRODUCT_ONLY(1) NOT_PRODUCT(4) // for _deoptimization_hist
1.93 + };
1.94 +
1.95 + enum UnpackType {
1.96 + Unpack_deopt = 0, // normal deoptimization, use pc computed in unpack_vframe_on_stack
1.97 + Unpack_exception = 1, // exception is pending
1.98 + Unpack_uncommon_trap = 2, // redo last byte code (C2 only)
1.99 + Unpack_reexecute = 3 // reexecute bytecode (C1 only)
1.100 + };
1.101 +
1.102 + // Checks all compiled methods. Invalid methods are deleted and
1.103 + // corresponding activations are deoptimized.
1.104 + static int deoptimize_dependents();
1.105 +
1.106 + // Deoptimizes a frame lazily. nmethod gets patched deopt happens on return to the frame
1.107 + static void deoptimize(JavaThread* thread, frame fr, RegisterMap *reg_map);
1.108 +
1.109 + private:
1.110 + // Does the actual work for deoptimizing a single frame
1.111 + static void deoptimize_single_frame(JavaThread* thread, frame fr);
1.112 +
1.113 + // Helper function to revoke biases of all monitors in frame if UseBiasedLocking
1.114 + // is enabled
1.115 + static void revoke_biases_of_monitors(JavaThread* thread, frame fr, RegisterMap* map);
1.116 + // Helper function to revoke biases of all monitors in frames
1.117 + // executing in a particular CodeBlob if UseBiasedLocking is enabled
1.118 + static void revoke_biases_of_monitors(CodeBlob* cb);
1.119 +
1.120 +#ifdef COMPILER2
1.121 + // Support for restoring non-escaping objects
1.122 + static bool realloc_objects(JavaThread* thread, frame* fr, GrowableArray<ScopeValue*>* objects, TRAPS);
1.123 + static void reassign_type_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, typeArrayOop obj, BasicType type);
1.124 + static void reassign_object_array_elements(frame* fr, RegisterMap* reg_map, ObjectValue* sv, objArrayOop obj);
1.125 + static void reassign_fields(frame* fr, RegisterMap* reg_map, GrowableArray<ScopeValue*>* objects);
1.126 + static void relock_objects(GrowableArray<MonitorInfo*>* monitors, JavaThread* thread);
1.127 + NOT_PRODUCT(static void print_objects(GrowableArray<ScopeValue*>* objects);)
1.128 +#endif // COMPILER2
1.129 +
1.130 + public:
1.131 + static vframeArray* create_vframeArray(JavaThread* thread, frame fr, RegisterMap *reg_map, GrowableArray<compiledVFrame*>* chunk);
1.132 +
1.133 + // Interface used for unpacking deoptimized frames
1.134 +
1.135 + // UnrollBlock is returned by fetch_unroll_info() to the deoptimization handler (blob).
1.136 + // This is only a CheapObj to ease debugging after a deopt failure
1.137 + class UnrollBlock : public CHeapObj<mtCompiler> {
1.138 + private:
1.139 + int _size_of_deoptimized_frame; // Size, in bytes, of current deoptimized frame
1.140 + int _caller_adjustment; // Adjustment, in bytes, to caller's SP by initial interpreted frame
1.141 + int _number_of_frames; // Number frames to unroll
1.142 + int _total_frame_sizes; // Total of number*sizes frames
1.143 + intptr_t* _frame_sizes; // Array of frame sizes, in bytes, for unrolling the stack
1.144 + address* _frame_pcs; // Array of frame pc's, in bytes, for unrolling the stack
1.145 + intptr_t* _register_block; // Block for storing callee-saved registers.
1.146 + BasicType _return_type; // Tells if we have to restore double or long return value
1.147 + intptr_t _initial_info; // Platform dependent data for the sender frame (was FP on x86)
1.148 + int _caller_actual_parameters; // The number of actual arguments at the
1.149 + // interpreted caller of the deoptimized frame
1.150 +
1.151 + // The following fields are used as temps during the unpacking phase
1.152 + // (which is tight on registers, especially on x86). They really ought
1.153 + // to be PD variables but that involves moving this class into its own
1.154 + // file to use the pd include mechanism. Maybe in a later cleanup ...
1.155 + intptr_t _counter_temp; // SHOULD BE PD VARIABLE (x86 frame count temp)
1.156 + intptr_t _unpack_kind; // SHOULD BE PD VARIABLE (x86 unpack kind)
1.157 + intptr_t _sender_sp_temp; // SHOULD BE PD VARIABLE (x86 sender_sp)
1.158 + public:
1.159 + // Constructor
1.160 + UnrollBlock(int size_of_deoptimized_frame,
1.161 + int caller_adjustment,
1.162 + int caller_actual_parameters,
1.163 + int number_of_frames,
1.164 + intptr_t* frame_sizes,
1.165 + address* frames_pcs,
1.166 + BasicType return_type);
1.167 + ~UnrollBlock();
1.168 +
1.169 + // Returns where a register is located.
1.170 + intptr_t* value_addr_at(int register_number) const;
1.171 +
1.172 + // Accessors
1.173 + intptr_t* frame_sizes() const { return _frame_sizes; }
1.174 + int number_of_frames() const { return _number_of_frames; }
1.175 + address* frame_pcs() const { return _frame_pcs ; }
1.176 +
1.177 + // Returns the total size of frames
1.178 + int size_of_frames() const;
1.179 +
1.180 + void set_initial_info(intptr_t info) { _initial_info = info; }
1.181 +
1.182 + int caller_actual_parameters() const { return _caller_actual_parameters; }
1.183 +
1.184 + // Accessors used by the code generator for the unpack stub.
1.185 + static int size_of_deoptimized_frame_offset_in_bytes() { return offset_of(UnrollBlock, _size_of_deoptimized_frame); }
1.186 + static int caller_adjustment_offset_in_bytes() { return offset_of(UnrollBlock, _caller_adjustment); }
1.187 + static int number_of_frames_offset_in_bytes() { return offset_of(UnrollBlock, _number_of_frames); }
1.188 + static int frame_sizes_offset_in_bytes() { return offset_of(UnrollBlock, _frame_sizes); }
1.189 + static int total_frame_sizes_offset_in_bytes() { return offset_of(UnrollBlock, _total_frame_sizes); }
1.190 + static int frame_pcs_offset_in_bytes() { return offset_of(UnrollBlock, _frame_pcs); }
1.191 + static int register_block_offset_in_bytes() { return offset_of(UnrollBlock, _register_block); }
1.192 + static int return_type_offset_in_bytes() { return offset_of(UnrollBlock, _return_type); }
1.193 + static int counter_temp_offset_in_bytes() { return offset_of(UnrollBlock, _counter_temp); }
1.194 + static int initial_info_offset_in_bytes() { return offset_of(UnrollBlock, _initial_info); }
1.195 + static int unpack_kind_offset_in_bytes() { return offset_of(UnrollBlock, _unpack_kind); }
1.196 + static int sender_sp_temp_offset_in_bytes() { return offset_of(UnrollBlock, _sender_sp_temp); }
1.197 +
1.198 + BasicType return_type() const { return _return_type; }
1.199 + void print();
1.200 + };
1.201 +
1.202 + //** Returns an UnrollBlock continuing information
1.203 + // how to make room for the resulting interpreter frames.
1.204 + // Called by assembly stub after execution has returned to
1.205 + // deoptimized frame.
1.206 + // @argument thread. Thread where stub_frame resides.
1.207 + // @see OptoRuntime::deoptimization_fetch_unroll_info_C
1.208 + static UnrollBlock* fetch_unroll_info(JavaThread* thread);
1.209 +
1.210 + //** Unpacks vframeArray onto execution stack
1.211 + // Called by assembly stub after execution has returned to
1.212 + // deoptimized frame and after the stack unrolling.
1.213 + // @argument thread. Thread where stub_frame resides.
1.214 + // @argument exec_mode. Determines how execution should be continuted in top frame.
1.215 + // 0 means continue after current byte code
1.216 + // 1 means exception has happened, handle exception
1.217 + // 2 means reexecute current bytecode (for uncommon traps).
1.218 + // @see OptoRuntime::deoptimization_unpack_frames_C
1.219 + // Return BasicType of call return type, if any
1.220 + static BasicType unpack_frames(JavaThread* thread, int exec_mode);
1.221 +
1.222 + // Cleans up deoptimization bits on thread after unpacking or in the
1.223 + // case of an exception.
1.224 + static void cleanup_deopt_info(JavaThread *thread,
1.225 + vframeArray * array);
1.226 +
1.227 + // Restores callee saved values from deoptimized frame into oldest interpreter frame
1.228 + // so caller of the deoptimized frame will get back the values it expects.
1.229 + static void unwind_callee_save_values(frame* f, vframeArray* vframe_array);
1.230 +
1.231 + //** Performs an uncommon trap for compiled code.
1.232 + // The top most compiler frame is converted into interpreter frames
1.233 + static UnrollBlock* uncommon_trap(JavaThread* thread, jint unloaded_class_index);
1.234 + // Helper routine that enters the VM and may block
1.235 + static void uncommon_trap_inner(JavaThread* thread, jint unloaded_class_index);
1.236 +
1.237 + //** Deoptimizes the frame identified by id.
1.238 + // Only called from VMDeoptimizeFrame
1.239 + // @argument thread. Thread where stub_frame resides.
1.240 + // @argument id. id of frame that should be deoptimized.
1.241 + static void deoptimize_frame_internal(JavaThread* thread, intptr_t* id);
1.242 +
1.243 + // If thread is not the current thread then execute
1.244 + // VM_DeoptimizeFrame otherwise deoptimize directly.
1.245 + static void deoptimize_frame(JavaThread* thread, intptr_t* id);
1.246 +
1.247 + // Statistics
1.248 + static void gather_statistics(DeoptReason reason, DeoptAction action,
1.249 + Bytecodes::Code bc = Bytecodes::_illegal);
1.250 + static void print_statistics();
1.251 +
1.252 + // How much room to adjust the last frame's SP by, to make space for
1.253 + // the callee's interpreter frame (which expects locals to be next to
1.254 + // incoming arguments)
1.255 + static int last_frame_adjust(int callee_parameters, int callee_locals);
1.256 +
1.257 + // trap_request codes
1.258 + static DeoptReason trap_request_reason(int trap_request) {
1.259 + if (trap_request < 0)
1.260 + return (DeoptReason)
1.261 + ((~(trap_request) >> _reason_shift) & right_n_bits(_reason_bits));
1.262 + else
1.263 + // standard reason for unloaded CP entry
1.264 + return Reason_unloaded;
1.265 + }
1.266 + static DeoptAction trap_request_action(int trap_request) {
1.267 + if (trap_request < 0)
1.268 + return (DeoptAction)
1.269 + ((~(trap_request) >> _action_shift) & right_n_bits(_action_bits));
1.270 + else
1.271 + // standard action for unloaded CP entry
1.272 + return _unloaded_action;
1.273 + }
1.274 + static int trap_request_index(int trap_request) {
1.275 + if (trap_request < 0)
1.276 + return -1;
1.277 + else
1.278 + return trap_request;
1.279 + }
1.280 + static int make_trap_request(DeoptReason reason, DeoptAction action,
1.281 + int index = -1) {
1.282 + assert((1 << _reason_bits) >= Reason_LIMIT, "enough bits");
1.283 + assert((1 << _action_bits) >= Action_LIMIT, "enough bits");
1.284 + int trap_request;
1.285 + if (index != -1)
1.286 + trap_request = index;
1.287 + else
1.288 + trap_request = (~(((reason) << _reason_shift)
1.289 + + ((action) << _action_shift)));
1.290 + assert(reason == trap_request_reason(trap_request), "valid reason");
1.291 + assert(action == trap_request_action(trap_request), "valid action");
1.292 + assert(index == trap_request_index(trap_request), "valid index");
1.293 + return trap_request;
1.294 + }
1.295 +
1.296 + // The trap_state stored in a MDO is decoded here.
1.297 + // It records two items of information.
1.298 + // reason: If a deoptimization happened here, what its reason was,
1.299 + // or if there were multiple deopts with differing reasons.
1.300 + // recompiled: If a deoptimization here triggered a recompilation.
1.301 + // Note that not all reasons are recorded per-bci.
1.302 + static DeoptReason trap_state_reason(int trap_state);
1.303 + static int trap_state_has_reason(int trap_state, int reason);
1.304 + static int trap_state_add_reason(int trap_state, int reason);
1.305 + static bool trap_state_is_recompiled(int trap_state);
1.306 + static int trap_state_set_recompiled(int trap_state, bool z);
1.307 + static const char* format_trap_state(char* buf, size_t buflen,
1.308 + int trap_state);
1.309 +
1.310 + static bool reason_is_recorded_per_bytecode(DeoptReason reason) {
1.311 + return reason > Reason_none && reason <= Reason_RECORDED_LIMIT;
1.312 + }
1.313 +
1.314 + static DeoptReason reason_recorded_per_bytecode_if_any(DeoptReason reason) {
1.315 + if (reason_is_recorded_per_bytecode(reason))
1.316 + return reason;
1.317 + else if (reason == Reason_div0_check) // null check due to divide-by-zero?
1.318 + return Reason_null_check; // recorded per BCI as a null check
1.319 + else if (reason == Reason_speculate_class_check)
1.320 + return Reason_class_check;
1.321 + else
1.322 + return Reason_none;
1.323 + }
1.324 +
1.325 + static bool reason_is_speculate(int reason) {
1.326 + if (reason == Reason_speculate_class_check) {
1.327 + return true;
1.328 + }
1.329 + return false;
1.330 + }
1.331 +
1.332 + static uint per_method_trap_limit(int reason) {
1.333 + return reason_is_speculate(reason) ? (uint)PerMethodSpecTrapLimit : (uint)PerMethodTrapLimit;
1.334 + }
1.335 +
1.336 + static const char* trap_reason_name(int reason);
1.337 + static const char* trap_action_name(int action);
1.338 + // Format like reason='foo' action='bar' index='123'.
1.339 + // This is suitable both for XML and for tty output.
1.340 + static const char* format_trap_request(char* buf, size_t buflen,
1.341 + int trap_request);
1.342 +
1.343 + static jint total_deoptimization_count();
1.344 + static jint deoptimization_count(DeoptReason reason);
1.345 +
1.346 + // JVMTI PopFrame support
1.347 +
1.348 + // Preserves incoming arguments to the popped frame when it is
1.349 + // returning to a deoptimized caller
1.350 + static void popframe_preserve_args(JavaThread* thread, int bytes_to_save, void* start_address);
1.351 +
1.352 + private:
1.353 + static MethodData* get_method_data(JavaThread* thread, methodHandle m, bool create_if_missing);
1.354 + // Update the mdo's count and per-BCI reason bits, returning previous state:
1.355 + static ProfileData* query_update_method_data(MethodData* trap_mdo,
1.356 + int trap_bci,
1.357 + DeoptReason reason,
1.358 + Method* compiled_method,
1.359 + //outputs:
1.360 + uint& ret_this_trap_count,
1.361 + bool& ret_maybe_prior_trap,
1.362 + bool& ret_maybe_prior_recompile);
1.363 + // class loading support for uncommon trap
1.364 + static void load_class_by_index(constantPoolHandle constant_pool, int index, TRAPS);
1.365 + static void load_class_by_index(constantPoolHandle constant_pool, int index);
1.366 +
1.367 + static UnrollBlock* fetch_unroll_info_helper(JavaThread* thread);
1.368 +
1.369 + static DeoptAction _unloaded_action; // == Action_reinterpret;
1.370 + static const char* _trap_reason_name[Reason_LIMIT];
1.371 + static const char* _trap_action_name[Action_LIMIT];
1.372 +
1.373 + static juint _deoptimization_hist[Reason_LIMIT][1+Action_LIMIT][BC_CASE_LIMIT];
1.374 + // Note: Histogram array size is 1-2 Kb.
1.375 +
1.376 + public:
1.377 + static void update_method_data_from_interpreter(MethodData* trap_mdo, int trap_bci, int reason);
1.378 +};
1.379 +
1.380 +class DeoptimizationMarker : StackObj { // for profiling
1.381 + static bool _is_active;
1.382 +public:
1.383 + DeoptimizationMarker() { _is_active = true; }
1.384 + ~DeoptimizationMarker() { _is_active = false; }
1.385 + static bool is_active() { return _is_active; }
1.386 +};
1.387 +
1.388 +#endif // SHARE_VM_RUNTIME_DEOPTIMIZATION_HPP
