1/*
2 * Copyright (c) 1997, 2019, 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.
22 *
23 */
24
25#include "precompiled.hpp"
26#include "interpreter/invocationCounter.hpp"
27#include "runtime/frame.hpp"
28#include "runtime/handles.inline.hpp"
29
30
31// Implementation of InvocationCounter
32
33void InvocationCounter::init() {
34 _counter = 0; // reset all the bits, including the sticky carry
35 reset();
36}
37
38void InvocationCounter::reset() {
39 // Only reset the state and don't make the method look like it's never
40 // been executed
41 set_state(wait_for_compile);
42}
43
44void InvocationCounter::set_carry() {
45 set_carry_flag();
46 // The carry bit now indicates that this counter had achieved a very
47 // large value. Now reduce the value, so that the method can be
48 // executed many more times before re-entering the VM.
49 int old_count = count();
50 int new_count = MIN2(old_count, (int) (CompileThreshold / 2));
51 // prevent from going to zero, to distinguish from never-executed methods
52 if (new_count == 0) new_count = 1;
53 if (old_count != new_count) set(state(), new_count);
54}
55
56void InvocationCounter::set_state(State state) {
57 assert(0 <= state && state < number_of_states, "illegal state");
58 int init = _init[state];
59 // prevent from going to zero, to distinguish from never-executed methods
60 if (init == 0 && count() > 0) init = 1;
61 int carry = (_counter & carry_mask); // the carry bit is sticky
62 _counter = (init << number_of_noncount_bits) | carry | state;
63}
64
65
66void InvocationCounter::print() {
67 tty->print_cr("invocation count: up = %d, limit = %d, carry = %s, state = %s",
68 count(), limit(),
69 carry() ? "true" : "false",
70 state_as_string(state()));
71}
72
73void InvocationCounter::print_short() {
74 tty->print(" [%d%s;%s]", count(), carry()?"+carry":"", state_as_short_string(state()));
75}
76
77// Initialization
78
79int InvocationCounter::_init [InvocationCounter::number_of_states];
80InvocationCounter::Action InvocationCounter::_action[InvocationCounter::number_of_states];
81
82#ifdef CC_INTERP
83int InvocationCounter::InterpreterInvocationLimit;
84int InvocationCounter::InterpreterBackwardBranchLimit;
85#endif
86
87const char* InvocationCounter::state_as_string(State state) {
88 switch (state) {
89 case wait_for_nothing : return "wait_for_nothing";
90 case wait_for_compile : return "wait_for_compile";
91 default:
92 ShouldNotReachHere();
93 return NULL;
94 }
95}
96
97const char* InvocationCounter::state_as_short_string(State state) {
98 switch (state) {
99 case wait_for_nothing : return "not comp.";
100 case wait_for_compile : return "compileable";
101 default:
102 ShouldNotReachHere();
103 return NULL;
104 }
105}
106
107
108static address do_nothing(const methodHandle& method, TRAPS) {
109 // dummy action for inactive invocation counters
110 MethodCounters* mcs = method->method_counters();
111 assert(mcs != NULL, "");
112 mcs->invocation_counter()->set_carry();
113 mcs->invocation_counter()->set_state(InvocationCounter::wait_for_nothing);
114 return NULL;
115}
116
117
118static address do_decay(const methodHandle& method, TRAPS) {
119 // decay invocation counters so compilation gets delayed
120 MethodCounters* mcs = method->method_counters();
121 assert(mcs != NULL, "");
122 mcs->invocation_counter()->decay();
123 return NULL;
124}
125
126
127void InvocationCounter::def(State state, int init, Action action) {
128 assert(0 <= state && state < number_of_states, "illegal state");
129 assert(0 <= init && init < count_limit, "initial value out of range");
130 _init [state] = init;
131 _action[state] = action;
132}
133
134void InvocationCounter::reinitialize() {
135 // define states
136 guarantee((int)number_of_states <= (int)state_limit, "adjust number_of_state_bits");
137 def(wait_for_nothing, 0, do_nothing);
138 def(wait_for_compile, 0, do_decay);
139
140#ifdef CC_INTERP
141 InterpreterInvocationLimit = CompileThreshold << number_of_noncount_bits;
142
143 // When methodData is collected, the backward branch limit is compared against a
144 // methodData counter, rather than an InvocationCounter. In the former case, we
145 // don't need the shift by number_of_noncount_bits, but we do need to adjust
146 // the factor by which we scale the threshold.
147 if (ProfileInterpreter) {
148 InterpreterBackwardBranchLimit = (int)((int64_t)CompileThreshold * (OnStackReplacePercentage - InterpreterProfilePercentage) / 100);
149 } else {
150 InterpreterBackwardBranchLimit = (int)(((int64_t)CompileThreshold * OnStackReplacePercentage / 100) << number_of_noncount_bits);
151 }
152
153 assert(0 <= InterpreterBackwardBranchLimit, "OSR threshold should be non-negative");
154#endif
155}
156
157void invocationCounter_init() {
158 InvocationCounter::reinitialize();
159}
160