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 package org.graalvm.compiler.java; 24 25 import java.util.List; 26 import java.util.Map; 27 import java.util.stream.Collectors; 28 29 import org.graalvm.compiler.nodes.AbstractBeginNode; 30 import org.graalvm.compiler.nodes.AbstractMergeNode; 31 import org.graalvm.compiler.nodes.ControlSplitNode; 32 import org.graalvm.compiler.nodes.FixedNode; 33 import org.graalvm.compiler.nodes.LoopBeginNode; 34 import org.graalvm.compiler.nodes.LoopExitNode; 35 import org.graalvm.compiler.nodes.StructuredGraph; 36 import org.graalvm.compiler.nodes.cfg.ControlFlowGraph; 37 import org.graalvm.compiler.phases.Phase; 38 import org.graalvm.compiler.phases.graph.ReentrantNodeIterator; 39 40 public final class ComputeLoopFrequenciesClosure extends ReentrantNodeIterator.NodeIteratorClosure<Double> { 41 42 private static final ComputeLoopFrequenciesClosure INSTANCE = new ComputeLoopFrequenciesClosure(); 43 44 private ComputeLoopFrequenciesClosure() { 45 // nothing to do 46 } 47 48 @Override 49 protected Double processNode(FixedNode node, Double currentState) { 50 // normal nodes never change the probability of a path 51 return currentState; 52 } 53 54 @Override 55 protected Double merge(AbstractMergeNode merge, List<Double> states) { 56 // a merge has the sum of all predecessor probabilities 57 return states.stream().collect(Collectors.summingDouble(d -> d)); 58 } 59 60 @Override 61 protected Double afterSplit(AbstractBeginNode node, Double oldState) { 62 // a control split splits up the probability 63 ControlSplitNode split = (ControlSplitNode) node.predecessor(); 64 return oldState * split.probability(node); 65 } 66 67 @Override 68 protected Map<LoopExitNode, Double> processLoop(LoopBeginNode loop, Double initialState) { 69 Map<LoopExitNode, Double> exitStates = ReentrantNodeIterator.processLoop(this, loop, 1D).exitStates; 70 71 double exitProbability = exitStates.values().stream().mapToDouble(d -> d).sum(); 72 exitProbability = Math.min(1D, exitProbability); 73 if (exitProbability < ControlFlowGraph.MIN_PROBABILITY) { 74 exitProbability = ControlFlowGraph.MIN_PROBABILITY; 75 } 76 assert exitProbability <= 1D && exitProbability >= 0D; 77 double loopFrequency = 1D / exitProbability; 78 loop.setLoopFrequency(loopFrequency); 79 80 double adjustmentFactor = initialState * loopFrequency; 81 exitStates.replaceAll((exitNode, probability) -> multiplySaturate(probability, adjustmentFactor)); 82 83 return exitStates; 84 } 85 86 /** 87 * Multiplies a and b and saturates the result to {@link ControlFlowGraph#MAX_PROBABILITY}. 88 */ 89 public static double multiplySaturate(double a, double b) { 90 double r = a * b; 91 if (r > ControlFlowGraph.MAX_PROBABILITY) { | 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 package org.graalvm.compiler.java; 24 25 import java.util.List; 26 27 import org.graalvm.compiler.nodes.AbstractBeginNode; 28 import org.graalvm.compiler.nodes.AbstractMergeNode; 29 import org.graalvm.compiler.nodes.ControlSplitNode; 30 import org.graalvm.compiler.nodes.FixedNode; 31 import org.graalvm.compiler.nodes.LoopBeginNode; 32 import org.graalvm.compiler.nodes.LoopExitNode; 33 import org.graalvm.compiler.nodes.StructuredGraph; 34 import org.graalvm.compiler.nodes.cfg.ControlFlowGraph; 35 import org.graalvm.compiler.phases.Phase; 36 import org.graalvm.compiler.phases.graph.ReentrantNodeIterator; 37 import org.graalvm.util.EconomicMap; 38 39 public final class ComputeLoopFrequenciesClosure extends ReentrantNodeIterator.NodeIteratorClosure<Double> { 40 41 private static final ComputeLoopFrequenciesClosure INSTANCE = new ComputeLoopFrequenciesClosure(); 42 43 private ComputeLoopFrequenciesClosure() { 44 // nothing to do 45 } 46 47 @Override 48 protected Double processNode(FixedNode node, Double currentState) { 49 // normal nodes never change the probability of a path 50 return currentState; 51 } 52 53 @Override 54 protected Double merge(AbstractMergeNode merge, List<Double> states) { 55 // a merge has the sum of all predecessor probabilities 56 double result = 0.0; 57 for (double d : states) { 58 result += d; 59 } 60 return result; 61 } 62 63 @Override 64 protected Double afterSplit(AbstractBeginNode node, Double oldState) { 65 // a control split splits up the probability 66 ControlSplitNode split = (ControlSplitNode) node.predecessor(); 67 return oldState * split.probability(node); 68 } 69 70 @Override 71 protected EconomicMap<LoopExitNode, Double> processLoop(LoopBeginNode loop, Double initialState) { 72 EconomicMap<LoopExitNode, Double> exitStates = ReentrantNodeIterator.processLoop(this, loop, 1D).exitStates; 73 74 double exitProbability = 0.0; 75 for (double d : exitStates.getValues()) { 76 exitProbability += d; 77 } 78 exitProbability = Math.min(1D, exitProbability); 79 if (exitProbability < ControlFlowGraph.MIN_PROBABILITY) { 80 exitProbability = ControlFlowGraph.MIN_PROBABILITY; 81 } 82 assert exitProbability <= 1D && exitProbability >= 0D; 83 double loopFrequency = 1D / exitProbability; 84 loop.setLoopFrequency(loopFrequency); 85 86 double adjustmentFactor = initialState * loopFrequency; 87 exitStates.replaceAll((exitNode, probability) -> multiplySaturate(probability, adjustmentFactor)); 88 89 return exitStates; 90 } 91 92 /** 93 * Multiplies a and b and saturates the result to {@link ControlFlowGraph#MAX_PROBABILITY}. 94 */ 95 public static double multiplySaturate(double a, double b) { 96 double r = a * b; 97 if (r > ControlFlowGraph.MAX_PROBABILITY) { |