1 /* 2 * Copyright (c) 1997, 2010, 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 "incls/_precompiled.incl" 26 # include "incls/_invocationCounter.cpp.incl" 27 28 29 // Implementation of InvocationCounter 30 31 void InvocationCounter::init() { 32 _counter = 0; // reset all the bits, including the sticky carry 33 reset(); 34 } 35 36 void InvocationCounter::reset() { 37 // Only reset the state and don't make the method look like it's never 38 // been executed 39 set_state(wait_for_compile); 40 } 41 42 void InvocationCounter::set_carry() { 43 set_carry_flag(); 44 // The carry bit now indicates that this counter had achieved a very 45 // large value. Now reduce the value, so that the method can be 46 // executed many more times before re-entering the VM. 47 int old_count = count(); 48 int new_count = MIN2(old_count, (int) (CompileThreshold / 2)); 49 // prevent from going to zero, to distinguish from never-executed methods 50 if (new_count == 0) new_count = 1; 51 if (old_count != new_count) set(state(), new_count); 52 } 53 54 void InvocationCounter::set_state(State state) { 55 assert(0 <= state && state < number_of_states, "illegal state"); 56 int init = _init[state]; 57 // prevent from going to zero, to distinguish from never-executed methods 58 if (init == 0 && count() > 0) init = 1; 59 int carry = (_counter & carry_mask); // the carry bit is sticky 60 _counter = (init << number_of_noncount_bits) | carry | state; 61 } 62 63 64 void InvocationCounter::print() { 65 tty->print_cr("invocation count: up = %d, limit = %d, carry = %s, state = %s", 66 count(), limit(), 67 carry() ? "true" : "false", 68 state_as_string(state())); 69 } 70 71 void InvocationCounter::print_short() { 72 tty->print(" [%d%s;%s]", count(), carry()?"+carry":"", state_as_short_string(state())); 73 } 74 75 // Initialization 76 77 int InvocationCounter::_init [InvocationCounter::number_of_states]; 78 InvocationCounter::Action InvocationCounter::_action[InvocationCounter::number_of_states]; 79 int InvocationCounter::InterpreterInvocationLimit; 80 int InvocationCounter::InterpreterBackwardBranchLimit; 81 int InvocationCounter::InterpreterProfileLimit; 82 83 84 const char* InvocationCounter::state_as_string(State state) { 85 switch (state) { 86 case wait_for_nothing : return "wait_for_nothing"; 87 case wait_for_compile : return "wait_for_compile"; 88 } 89 ShouldNotReachHere(); 90 return NULL; 91 } 92 93 const char* InvocationCounter::state_as_short_string(State state) { 94 switch (state) { 95 case wait_for_nothing : return "not comp."; 96 case wait_for_compile : return "compileable"; 97 } 98 ShouldNotReachHere(); 99 return NULL; 100 } 101 102 103 static address do_nothing(methodHandle method, TRAPS) { 104 // dummy action for inactive invocation counters 105 method->invocation_counter()->set_carry(); 106 method->invocation_counter()->set_state(InvocationCounter::wait_for_nothing); 107 return NULL; 108 } 109 110 111 static address do_decay(methodHandle method, TRAPS) { 112 // decay invocation counters so compilation gets delayed 113 method->invocation_counter()->decay(); 114 return NULL; 115 } 116 117 118 void InvocationCounter::def(State state, int init, Action action) { 119 assert(0 <= state && state < number_of_states, "illegal state"); 120 assert(0 <= init && init < count_limit, "initial value out of range"); 121 _init [state] = init; 122 _action[state] = action; 123 } 124 125 address dummy_invocation_counter_overflow(methodHandle m, TRAPS) { 126 ShouldNotReachHere(); 127 return NULL; 128 } 129 130 void InvocationCounter::reinitialize(bool delay_overflow) { 131 // define states 132 guarantee((int)number_of_states <= (int)state_limit, "adjust number_of_state_bits"); 133 def(wait_for_nothing, 0, do_nothing); 134 if (delay_overflow) { 135 def(wait_for_compile, 0, do_decay); 136 } else { 137 def(wait_for_compile, 0, dummy_invocation_counter_overflow); 138 } 139 140 InterpreterInvocationLimit = CompileThreshold << number_of_noncount_bits; 141 InterpreterProfileLimit = ((CompileThreshold * InterpreterProfilePercentage) / 100)<< 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 = (CompileThreshold * (OnStackReplacePercentage - InterpreterProfilePercentage)) / 100; 149 } else { 150 InterpreterBackwardBranchLimit = ((CompileThreshold * OnStackReplacePercentage) / 100) << number_of_noncount_bits; 151 } 152 153 assert(0 <= InterpreterBackwardBranchLimit, 154 "OSR threshold should be non-negative"); 155 assert(0 <= InterpreterProfileLimit && 156 InterpreterProfileLimit <= InterpreterInvocationLimit, 157 "profile threshold should be less than the compilation threshold " 158 "and non-negative"); 159 } 160 161 void invocationCounter_init() { 162 InvocationCounter::reinitialize(DelayCompilationDuringStartup); 163 }