--- /dev/null
+/*******************************************************************************
+ * Copyright (c) 2000, 2004 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Common Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/cpl-v10.html
+ *
+ * Contributors:
+ * IBM Corporation - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.jdt.internal.compiler.flow;
+
+import org.eclipse.jdt.internal.compiler.impl.Constant;
+import org.eclipse.jdt.internal.compiler.lookup.FieldBinding;
+import org.eclipse.jdt.internal.compiler.lookup.LocalVariableBinding;
+import org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding;
+
+/**
+ * Record initialization status during definite assignment analysis
+ *
+ * No caching of pre-allocated instances.
+ */
+public class UnconditionalFlowInfo extends FlowInfo {
+
+
+ public long definiteInits;
+ public long potentialInits;
+ public long extraDefiniteInits[];
+ public long extraPotentialInits[];
+
+ public int reachMode; // by default
+
+ public int maxFieldCount;
+
+ // Constants
+ public static final int BitCacheSize = 64; // 64 bits in a long.
+
+ UnconditionalFlowInfo() {
+ this.reachMode = REACHABLE;
+ }
+
+ // unions of both sets of initialization - used for try/finally
+ public FlowInfo addInitializationsFrom(FlowInfo inits) {
+
+ if (this == DEAD_END)
+ return this;
+
+ UnconditionalFlowInfo otherInits = inits.unconditionalInits();
+ if (otherInits == DEAD_END)
+ return this;
+
+ // union of definitely assigned variables,
+ definiteInits |= otherInits.definiteInits;
+ // union of potentially set ones
+ potentialInits |= otherInits.potentialInits;
+
+ // treating extra storage
+ if (extraDefiniteInits != null) {
+ if (otherInits.extraDefiniteInits != null) {
+ // both sides have extra storage
+ int i = 0, length, otherLength;
+ if ((length = extraDefiniteInits.length) < (otherLength = otherInits.extraDefiniteInits.length)) {
+ // current storage is shorter -> grow current (could maybe reuse otherInits extra storage?)
+ System.arraycopy(extraDefiniteInits, 0, (extraDefiniteInits = new long[otherLength]), 0, length);
+ System.arraycopy(extraPotentialInits, 0, (extraPotentialInits = new long[otherLength]), 0, length);
+ while (i < length) {
+ extraDefiniteInits[i] |= otherInits.extraDefiniteInits[i];
+ extraPotentialInits[i] |= otherInits.extraPotentialInits[i++];
+ }
+ while (i < otherLength) {
+ extraPotentialInits[i] = otherInits.extraPotentialInits[i++];
+ }
+ } else {
+ // current storage is longer
+ while (i < otherLength) {
+ extraDefiniteInits[i] |= otherInits.extraDefiniteInits[i];
+ extraPotentialInits[i] |= otherInits.extraPotentialInits[i++];
+ }
+ while (i < length)
+ extraDefiniteInits[i++] = 0;
+ }
+ } else {
+ // no extra storage on otherInits
+ }
+ } else
+ if (otherInits.extraDefiniteInits != null) {
+ // no storage here, but other has extra storage.
+ int otherLength;
+ System.arraycopy(otherInits.extraDefiniteInits, 0, (extraDefiniteInits = new long[otherLength = otherInits.extraDefiniteInits.length]), 0, otherLength);
+ System.arraycopy(otherInits.extraPotentialInits, 0, (extraPotentialInits = new long[otherLength]), 0, otherLength);
+ }
+ return this;
+ }
+
+ // unions of both sets of initialization - used for try/finally
+ public FlowInfo addPotentialInitializationsFrom(FlowInfo inits) {
+
+ if (this == DEAD_END){
+ return this;
+ }
+
+ UnconditionalFlowInfo otherInits = inits.unconditionalInits();
+ if (otherInits == DEAD_END){
+ return this;
+ }
+ // union of potentially set ones
+ potentialInits |= otherInits.potentialInits;
+
+ // treating extra storage
+ if (extraDefiniteInits != null) {
+ if (otherInits.extraDefiniteInits != null) {
+ // both sides have extra storage
+ int i = 0, length, otherLength;
+ if ((length = extraDefiniteInits.length) < (otherLength = otherInits.extraDefiniteInits.length)) {
+ // current storage is shorter -> grow current (could maybe reuse otherInits extra storage?)
+ System.arraycopy(extraDefiniteInits, 0, (extraDefiniteInits = new long[otherLength]), 0, length);
+ System.arraycopy(extraPotentialInits, 0, (extraPotentialInits = new long[otherLength]), 0, length);
+ while (i < length) {
+ extraPotentialInits[i] |= otherInits.extraPotentialInits[i++];
+ }
+ while (i < otherLength) {
+ extraPotentialInits[i] = otherInits.extraPotentialInits[i++];
+ }
+ } else {
+ // current storage is longer
+ while (i < otherLength) {
+ extraPotentialInits[i] |= otherInits.extraPotentialInits[i++];
+ }
+ }
+ }
+ } else
+ if (otherInits.extraDefiniteInits != null) {
+ // no storage here, but other has extra storage.
+ int otherLength;
+ extraDefiniteInits = new long[otherLength = otherInits.extraDefiniteInits.length];
+ System.arraycopy(otherInits.extraPotentialInits, 0, (extraPotentialInits = new long[otherLength]), 0, otherLength);
+ }
+ return this;
+ }
+
+ /**
+ * Answers a copy of the current instance
+ */
+ public FlowInfo copy() {
+
+ // do not clone the DeadEnd
+ if (this == DEAD_END)
+ return this;
+
+ // look for an unused preallocated object
+ UnconditionalFlowInfo copy = new UnconditionalFlowInfo();
+
+ // copy slots
+ copy.definiteInits = this.definiteInits;
+ copy.potentialInits = this.potentialInits;
+ copy.reachMode = this.reachMode;
+ copy.maxFieldCount = this.maxFieldCount;
+
+ if (this.extraDefiniteInits != null) {
+ int length;
+ System.arraycopy(this.extraDefiniteInits, 0, (copy.extraDefiniteInits = new long[ (length = extraDefiniteInits.length)]), 0, length);
+ System.arraycopy(this.extraPotentialInits, 0, (copy.extraPotentialInits = new long[length]), 0, length);
+ }
+ return copy;
+ }
+
+ public UnconditionalFlowInfo discardFieldInitializations(){
+
+ int limit = this.maxFieldCount;
+
+ if (limit < BitCacheSize) {
+ long mask = (1L << limit)-1;
+ this.definiteInits &= ~mask;
+ this.potentialInits &= ~mask;
+ return this;
+ }
+
+ this.definiteInits = 0;
+ this.potentialInits = 0;
+
+ // use extra vector
+ if (extraDefiniteInits == null) {
+ return this; // if vector not yet allocated, then not initialized
+ }
+ int vectorIndex, length = this.extraDefiniteInits.length;
+ if ((vectorIndex = (limit / BitCacheSize) - 1) >= length) {
+ return this; // not enough room yet
+ }
+ for (int i = 0; i < vectorIndex; i++) {
+ this.extraDefiniteInits[i] = 0L;
+ this.extraPotentialInits[i] = 0L;
+ }
+ long mask = (1L << (limit % BitCacheSize))-1;
+ this.extraDefiniteInits[vectorIndex] &= ~mask;
+ this.extraPotentialInits[vectorIndex] &= ~mask;
+ return this;
+ }
+
+ public UnconditionalFlowInfo discardNonFieldInitializations(){
+
+ int limit = this.maxFieldCount;
+
+ if (limit < BitCacheSize) {
+ long mask = (1L << limit)-1;
+ this.definiteInits &= mask;
+ this.potentialInits &= mask;
+ return this;
+ }
+ // use extra vector
+ if (extraDefiniteInits == null) {
+ return this; // if vector not yet allocated, then not initialized
+ }
+ int vectorIndex, length = this.extraDefiniteInits.length;
+ if ((vectorIndex = (limit / BitCacheSize) - 1) >= length) {
+ return this; // not enough room yet
+ }
+ long mask = (1L << (limit % BitCacheSize))-1;
+ this.extraDefiniteInits[vectorIndex] &= mask;
+ this.extraPotentialInits[vectorIndex] &= mask;
+ for (int i = vectorIndex+1; i < length; i++) {
+ this.extraDefiniteInits[i] = 0L;
+ this.extraPotentialInits[i] = 0L;
+ }
+ return this;
+ }
+
+ public FlowInfo initsWhenFalse() {
+
+ return this;
+ }
+
+ public FlowInfo initsWhenTrue() {
+
+ return this;
+ }
+
+ /**
+ * Check status of definite assignment at a given position.
+ * It deals with the dual representation of the InitializationInfo2:
+ * bits for the first 64 entries, then an array of booleans.
+ */
+ final private boolean isDefinitelyAssigned(int position) {
+
+ // Dependant of CodeStream.isDefinitelyAssigned(..)
+ // id is zero-based
+ if (position < BitCacheSize) {
+ return (definiteInits & (1L << position)) != 0; // use bits
+ }
+ // use extra vector
+ if (extraDefiniteInits == null)
+ return false; // if vector not yet allocated, then not initialized
+ int vectorIndex;
+ if ((vectorIndex = (position / BitCacheSize) - 1) >= extraDefiniteInits.length)
+ return false; // if not enough room in vector, then not initialized
+ return ((extraDefiniteInits[vectorIndex]) & (1L << (position % BitCacheSize))) != 0;
+ }
+
+ /**
+ * Check status of definite assignment for a field.
+ */
+ final public boolean isDefinitelyAssigned(FieldBinding field) {
+
+ // Dependant of CodeStream.isDefinitelyAssigned(..)
+ // We do not want to complain in unreachable code
+ if ((this.reachMode & UNREACHABLE) != 0)
+ return true;
+ return isDefinitelyAssigned(field.id);
+ }
+
+ /**
+ * Check status of definite assignment for a local.
+ */
+ final public boolean isDefinitelyAssigned(LocalVariableBinding local) {
+
+ // Dependant of CodeStream.isDefinitelyAssigned(..)
+ // We do not want to complain in unreachable code
+ if ((this.reachMode & UNREACHABLE) != 0)
+ return true;
+ if (local.isArgument) {
+ return true;
+ }
+ // final constants are inlined, and thus considered as always initialized
+ if (local.constant != Constant.NotAConstant) {
+ return true;
+ }
+ return isDefinitelyAssigned(local.id + maxFieldCount);
+ }
+
+ public boolean isReachable() {
+
+ return this.reachMode == REACHABLE;
+ }
+
+ /**
+ * Check status of potential assignment at a given position.
+ * It deals with the dual representation of the InitializationInfo3:
+ * bits for the first 64 entries, then an array of booleans.
+ */
+ final private boolean isPotentiallyAssigned(int position) {
+
+ // id is zero-based
+ if (position < BitCacheSize) {
+ // use bits
+ return (potentialInits & (1L << position)) != 0;
+ }
+ // use extra vector
+ if (extraPotentialInits == null)
+ return false; // if vector not yet allocated, then not initialized
+ int vectorIndex;
+ if ((vectorIndex = (position / BitCacheSize) - 1) >= extraPotentialInits.length)
+ return false; // if not enough room in vector, then not initialized
+ return ((extraPotentialInits[vectorIndex]) & (1L << (position % BitCacheSize))) != 0;
+ }
+
+ /**
+ * Check status of definite assignment for a field.
+ */
+ final public boolean isPotentiallyAssigned(FieldBinding field) {
+
+ return isPotentiallyAssigned(field.id);
+ }
+
+ /**
+ * Check status of potential assignment for a local.
+ */
+ final public boolean isPotentiallyAssigned(LocalVariableBinding local) {
+
+ if (local.isArgument) {
+ return true;
+ }
+ // final constants are inlined, and thus considered as always initialized
+ if (local.constant != Constant.NotAConstant) {
+ return true;
+ }
+ return isPotentiallyAssigned(local.id + maxFieldCount);
+ }
+
+ /**
+ * Record a definite assignment at a given position.
+ * It deals with the dual representation of the InitializationInfo2:
+ * bits for the first 64 entries, then an array of booleans.
+ */
+ final private void markAsDefinitelyAssigned(int position) {
+
+ if (this != DEAD_END) {
+
+ // position is zero-based
+ if (position < BitCacheSize) {
+ // use bits
+ long mask;
+ definiteInits |= (mask = 1L << position);
+ potentialInits |= mask;
+ } else {
+ // use extra vector
+ int vectorIndex = (position / BitCacheSize) - 1;
+ if (extraDefiniteInits == null) {
+ int length;
+ extraDefiniteInits = new long[length = vectorIndex + 1];
+ extraPotentialInits = new long[length];
+ } else {
+ int oldLength; // might need to grow the arrays
+ if (vectorIndex >= (oldLength = extraDefiniteInits.length)) {
+ System.arraycopy(extraDefiniteInits, 0, (extraDefiniteInits = new long[vectorIndex + 1]), 0, oldLength);
+ System.arraycopy(extraPotentialInits, 0, (extraPotentialInits = new long[vectorIndex + 1]), 0, oldLength);
+ }
+ }
+ long mask;
+ extraDefiniteInits[vectorIndex] |= (mask = 1L << (position % BitCacheSize));
+ extraPotentialInits[vectorIndex] |= mask;
+ }
+ }
+ }
+
+ /**
+ * Record a field got definitely assigned.
+ */
+ public void markAsDefinitelyAssigned(FieldBinding field) {
+ if (this != DEAD_END)
+ markAsDefinitelyAssigned(field.id);
+ }
+
+ /**
+ * Record a local got definitely assigned.
+ */
+ public void markAsDefinitelyAssigned(LocalVariableBinding local) {
+ if (this != DEAD_END)
+ markAsDefinitelyAssigned(local.id + maxFieldCount);
+ }
+
+ /**
+ * Clear initialization information at a given position.
+ * It deals with the dual representation of the InitializationInfo2:
+ * bits for the first 64 entries, then an array of booleans.
+ */
+ final private void markAsDefinitelyNotAssigned(int position) {
+ if (this != DEAD_END) {
+
+ // position is zero-based
+ if (position < BitCacheSize) {
+ // use bits
+ long mask;
+ definiteInits &= ~(mask = 1L << position);
+ potentialInits &= ~mask;
+ } else {
+ // use extra vector
+ int vectorIndex = (position / BitCacheSize) - 1;
+ if (extraDefiniteInits == null) {
+ return; // nothing to do, it was not yet set
+ }
+ // might need to grow the arrays
+ if (vectorIndex >= extraDefiniteInits.length) {
+ return; // nothing to do, it was not yet set
+ }
+ long mask;
+ extraDefiniteInits[vectorIndex] &= ~(mask = 1L << (position % BitCacheSize));
+ extraPotentialInits[vectorIndex] &= ~mask;
+ }
+ }
+ }
+
+ /**
+ * Clear the initialization info for a field
+ */
+ public void markAsDefinitelyNotAssigned(FieldBinding field) {
+
+ if (this != DEAD_END)
+ markAsDefinitelyNotAssigned(field.id);
+ }
+
+ /**
+ * Clear the initialization info for a local variable
+ */
+
+ public void markAsDefinitelyNotAssigned(LocalVariableBinding local) {
+
+ if (this != DEAD_END)
+ markAsDefinitelyNotAssigned(local.id + maxFieldCount);
+ }
+
+ /**
+ * Returns the receiver updated in the following way: <ul>
+ * <li> intersection of definitely assigned variables,
+ * <li> union of potentially assigned variables.
+ * </ul>
+ */
+ public UnconditionalFlowInfo mergedWith(UnconditionalFlowInfo otherInits) {
+
+ if (this == DEAD_END) return otherInits;
+ if (otherInits == DEAD_END) return this;
+
+ if ((this.reachMode & UNREACHABLE) != (otherInits.reachMode & UNREACHABLE)){
+ if ((this.reachMode & UNREACHABLE) != 0){
+ return otherInits;
+ }
+ return this;
+ }
+
+ // if one branch is not fake reachable, then the merged one is reachable
+ this.reachMode &= otherInits.reachMode;
+
+ // intersection of definitely assigned variables,
+ this.definiteInits &= otherInits.definiteInits;
+ // union of potentially set ones
+ this.potentialInits |= otherInits.potentialInits;
+
+ // treating extra storage
+ if (this.extraDefiniteInits != null) {
+ if (otherInits.extraDefiniteInits != null) {
+ // both sides have extra storage
+ int i = 0, length, otherLength;
+ if ((length = this.extraDefiniteInits.length) < (otherLength = otherInits.extraDefiniteInits.length)) {
+ // current storage is shorter -> grow current (could maybe reuse otherInits extra storage?)
+ System.arraycopy(this.extraDefiniteInits, 0, (this.extraDefiniteInits = new long[otherLength]), 0, length);
+ System.arraycopy(this.extraPotentialInits, 0, (this.extraPotentialInits = new long[otherLength]), 0, length);
+ while (i < length) {
+ this.extraDefiniteInits[i] &= otherInits.extraDefiniteInits[i];
+ this.extraPotentialInits[i] |= otherInits.extraPotentialInits[i++];
+ }
+ while (i < otherLength) {
+ this.extraPotentialInits[i] = otherInits.extraPotentialInits[i++];
+ }
+ } else {
+ // current storage is longer
+ while (i < otherLength) {
+ this.extraDefiniteInits[i] &= otherInits.extraDefiniteInits[i];
+ this.extraPotentialInits[i] |= otherInits.extraPotentialInits[i++];
+ }
+ while (i < length)
+ this.extraDefiniteInits[i++] = 0;
+ }
+ } else {
+ // no extra storage on otherInits
+ int i = 0, length = this.extraDefiniteInits.length;
+ while (i < length)
+ this.extraDefiniteInits[i++] = 0;
+ }
+ } else
+ if (otherInits.extraDefiniteInits != null) {
+ // no storage here, but other has extra storage.
+ int otherLength;
+ this.extraDefiniteInits = new long[otherLength = otherInits.extraDefiniteInits.length];
+ System.arraycopy(otherInits.extraPotentialInits, 0, (this.extraPotentialInits = new long[otherLength]), 0, otherLength);
+ }
+ return this;
+ }
+
+ /*
+ * Answer the total number of fields in enclosing types of a given type
+ */
+ static int numberOfEnclosingFields(ReferenceBinding type){
+
+ int count = 0;
+ type = type.enclosingType();
+ while(type != null) {
+ count += type.fieldCount();
+ type = type.enclosingType();
+ }
+ return count;
+ }
+
+ public int reachMode(){
+ return this.reachMode;
+ }
+
+ public FlowInfo setReachMode(int reachMode) {
+
+ if (this == DEAD_END) return this; // cannot modify DEAD_END
+
+ // reset optional inits when becoming unreachable
+ if ((this.reachMode & UNREACHABLE) == 0 && (reachMode & UNREACHABLE) != 0) {
+ this.potentialInits = 0;
+ if (this.extraPotentialInits != null){
+ for (int i = 0, length = this.extraPotentialInits.length; i < length; i++){
+ this.extraPotentialInits[i] = 0;
+ }
+ }
+ }
+ this.reachMode = reachMode;
+
+ return this;
+ }
+
+ public String toString(){
+
+ if (this == DEAD_END){
+ return "FlowInfo.DEAD_END"; //$NON-NLS-1$
+ }
+ return "FlowInfo<def: "+ this.definiteInits //$NON-NLS-1$
+ +", pot: " + this.potentialInits //$NON-NLS-1$
+ + ", reachable:" + ((this.reachMode & UNREACHABLE) == 0) //$NON-NLS-1$
+ +">"; //$NON-NLS-1$
+ }
+
+ public UnconditionalFlowInfo unconditionalInits() {
+
+ // also see conditional inits, where it requests them to merge
+ return this;
+ }
+}
projects / org.ibex.tool.git / blobdiff