Mercurial > hg > truffle
annotate src/share/vm/interpreter/invocationCounter.cpp @ 654:c664a0794f85
6805748: Assertion "don't reset to 0 -- could be mistaken for never-executed" in CompilationPolicy
Summary: Resetting the invocation counter for a method invocation event was setting count to zero for CompileThreshold=1, making it look like a never executed method.
Reviewed-by: phh, kamg, acorn, never
| author | coleenp |
|---|---|
| date | Fri, 20 Mar 2009 22:08:48 -0400 |
| parents | a61af66fc99e |
| children | bd02caa94611 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 * Copyright 1997-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
| 20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
| 21 * have any 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 _counter |= carry_mask; | |
| 44 | |
| 45 // The carry bit now indicates that this counter had achieved a very | |
| 46 // large value. Now reduce the value, so that the method can be | |
| 47 // executed many more times before re-entering the VM. | |
| 48 int old_count = count(); | |
| 49 int new_count = MIN2(old_count, (int) (CompileThreshold / 2)); | |
|
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c664a0794f85
6805748: Assertion "don't reset to 0 -- could be mistaken for never-executed" in CompilationPolicy
coleenp
parents:
0
diff
changeset
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50 // prevent from going to zero, to distinguish from never-executed methods |
|
c664a0794f85
6805748: Assertion "don't reset to 0 -- could be mistaken for never-executed" in CompilationPolicy
coleenp
parents:
0
diff
changeset
|
51 if (new_count == 0) new_count = 1; |
| 0 | 52 if (old_count != new_count) set(state(), new_count); |
| 53 } | |
| 54 | |
| 55 | |
| 56 void 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 | |
| 66 void 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 | |
| 73 void InvocationCounter::print_short() { | |
| 74 tty->print(" [%d%s;%s]", count(), carry()?"+carry":"", state_as_short_string(state())); | |
| 75 } | |
| 76 | |
| 77 // Initialization | |
| 78 | |
| 79 int InvocationCounter::_init [InvocationCounter::number_of_states]; | |
| 80 InvocationCounter::Action InvocationCounter::_action[InvocationCounter::number_of_states]; | |
| 81 int InvocationCounter::InterpreterInvocationLimit; | |
| 82 int InvocationCounter::InterpreterBackwardBranchLimit; | |
| 83 int InvocationCounter::InterpreterProfileLimit; | |
| 84 | |
| 85 // Tier1 limits | |
| 86 int InvocationCounter::Tier1InvocationLimit; | |
| 87 int InvocationCounter::Tier1BackEdgeLimit; | |
| 88 | |
| 89 | |
| 90 | |
| 91 const char* InvocationCounter::state_as_string(State state) { | |
| 92 switch (state) { | |
| 93 case wait_for_nothing : return "wait_for_nothing"; | |
| 94 case wait_for_compile : return "wait_for_compile"; | |
| 95 } | |
| 96 ShouldNotReachHere(); | |
| 97 return NULL; | |
| 98 } | |
| 99 | |
| 100 const char* InvocationCounter::state_as_short_string(State state) { | |
| 101 switch (state) { | |
| 102 case wait_for_nothing : return "not comp."; | |
| 103 case wait_for_compile : return "compileable"; | |
| 104 } | |
| 105 ShouldNotReachHere(); | |
| 106 return NULL; | |
| 107 } | |
| 108 | |
| 109 | |
| 110 static address do_nothing(methodHandle method, TRAPS) { | |
| 111 // dummy action for inactive invocation counters | |
| 112 method->invocation_counter()->set_carry(); | |
| 113 method->invocation_counter()->set_state(InvocationCounter::wait_for_nothing); | |
| 114 return NULL; | |
| 115 } | |
| 116 | |
| 117 | |
| 118 static address do_decay(methodHandle method, TRAPS) { | |
| 119 // decay invocation counters so compilation gets delayed | |
| 120 method->invocation_counter()->decay(); | |
| 121 return NULL; | |
| 122 } | |
| 123 | |
| 124 | |
| 125 void InvocationCounter::def(State state, int init, Action action) { | |
| 126 assert(0 <= state && state < number_of_states, "illegal state"); | |
| 127 assert(0 <= init && init < count_limit, "initial value out of range"); | |
| 128 _init [state] = init; | |
| 129 _action[state] = action; | |
| 130 } | |
| 131 | |
| 132 address dummy_invocation_counter_overflow(methodHandle m, TRAPS) { | |
| 133 ShouldNotReachHere(); | |
| 134 return NULL; | |
| 135 } | |
| 136 | |
| 137 void InvocationCounter::reinitialize(bool delay_overflow) { | |
| 138 // define states | |
| 139 guarantee((int)number_of_states <= (int)state_limit, "adjust number_of_state_bits"); | |
| 140 def(wait_for_nothing, 0, do_nothing); | |
| 141 if (delay_overflow) { | |
| 142 def(wait_for_compile, 0, do_decay); | |
| 143 } else { | |
| 144 def(wait_for_compile, 0, dummy_invocation_counter_overflow); | |
| 145 } | |
| 146 | |
| 147 InterpreterInvocationLimit = CompileThreshold << number_of_noncount_bits; | |
| 148 InterpreterProfileLimit = ((CompileThreshold * InterpreterProfilePercentage) / 100)<< number_of_noncount_bits; | |
| 149 Tier1InvocationLimit = Tier2CompileThreshold << number_of_noncount_bits; | |
| 150 Tier1BackEdgeLimit = Tier2BackEdgeThreshold << number_of_noncount_bits; | |
| 151 | |
| 152 // When methodData is collected, the backward branch limit is compared against a | |
| 153 // methodData counter, rather than an InvocationCounter. In the former case, we | |
| 154 // don't need the shift by number_of_noncount_bits, but we do need to adjust | |
| 155 // the factor by which we scale the threshold. | |
| 156 if (ProfileInterpreter) { | |
| 157 InterpreterBackwardBranchLimit = (CompileThreshold * (OnStackReplacePercentage - InterpreterProfilePercentage)) / 100; | |
| 158 } else { | |
| 159 InterpreterBackwardBranchLimit = ((CompileThreshold * OnStackReplacePercentage) / 100) << number_of_noncount_bits; | |
| 160 } | |
| 161 | |
| 162 assert(0 <= InterpreterBackwardBranchLimit, | |
| 163 "OSR threshold should be non-negative"); | |
| 164 assert(0 <= InterpreterProfileLimit && | |
| 165 InterpreterProfileLimit <= InterpreterInvocationLimit, | |
| 166 "profile threshold should be less than the compilation threshold " | |
| 167 "and non-negative"); | |
| 168 } | |
| 169 | |
| 170 void invocationCounter_init() { | |
| 171 InvocationCounter::reinitialize(DelayCompilationDuringStartup); | |
| 172 } |