Refactory
[phpeclipse.git] / net.sourceforge.phpeclipse / src / net / sourceforge / phpdt / internal / compiler / codegen / Label.java
index d75371e..3e09f1c 100644 (file)
 /*******************************************************************************
- * Copyright (c) 2000, 2001, 2002 International Business Machines Corp. and others.
+ * Copyright (c) 2000, 2003 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials 
- * are made available under the terms of the Common Public License v0.5 
+ * 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-v05.html
+ * http://www.eclipse.org/legal/cpl-v10.html
  * 
  * Contributors:
  *     IBM Corporation - initial API and implementation
- ******************************************************************************/
+ *******************************************************************************/
 package net.sourceforge.phpdt.internal.compiler.codegen;
 
-import net.sourceforge.phpdt.internal.compiler.lookup.LocalVariableBinding;
-import net.sourceforge.phpdt.internal.compiler.problem.AbortMethod;
-
 /**
  * This type is a port of smalltalks JavaLabel
  */
 public class Label {
-       public CodeStream codeStream;
+       // public CodeStream codeStream;
        final static int POS_NOT_SET = -1;
-       public int position = POS_NOT_SET; // position=POS_NOT_SET Then it's pos is not set.
-       public int[] forwardReferences = new int[10]; // Add an overflow check here.
+
+       public int position = POS_NOT_SET; // position=POS_NOT_SET Then it's pos is
+                                                                               // not set.
+
+       public int[] forwardReferences = new int[10]; // Add an overflow check
+                                                                                                       // here.
+
        public int forwardReferenceCount = 0;
-       private boolean isWide = false;
-public Label() {
-}
-/**
- * @param codeStream org.eclipse.jdt.internal.compiler.codegen.CodeStream
- */
-public Label(CodeStream codeStream) {
-       this.codeStream = codeStream;
-}
-/**
- * Add a forward refrence for the array.
- */
-void addForwardReference(int iPos) {
-       int length;
-       if (forwardReferenceCount >= (length = forwardReferences.length))
-               System.arraycopy(forwardReferences, 0, (forwardReferences = new int[2*length]), 0, length);
-       forwardReferences[forwardReferenceCount++] = iPos;
-}
-/**
- * Add a forward refrence for the array.
- */
-public void appendForwardReferencesFrom(Label otherLabel) {
-       int otherCount = otherLabel.forwardReferenceCount;
-       if (otherCount == 0) return;
-       int length = forwardReferences.length;
-       int neededSpace = otherCount + forwardReferenceCount;
-       if (neededSpace >= length){
-               System.arraycopy(forwardReferences, 0, (forwardReferences = new int[neededSpace]), 0, forwardReferenceCount);
-       }
-       // append other forward references at the end, so they will get updated as well
-       System.arraycopy(otherLabel.forwardReferences, 0, forwardReferences, forwardReferenceCount, otherCount);
-       forwardReferenceCount = neededSpace;
-}
-/*
-* Put down  a refernece to the array at the location in the codestream.
-*/
-void branch() {
-       if (position == POS_NOT_SET) {
-               addForwardReference(codeStream.position);
-               // Leave two bytes free to generate the jump afterwards
-               codeStream.position += 2;
-               codeStream.classFileOffset += 2;
-       } else { //Position is set. Write it!
-               codeStream.writeSignedShort((short) (position - codeStream.position + 1));
+
+       //private boolean isWide = false;
+
+       public Label() {
        }
-}
-/*
-* No support for wide branches yet
-*/
-void branchWide() {
-       if (position == POS_NOT_SET) {
-               addForwardReference(codeStream.position);
-               // Leave 4 bytes free to generate the jump offset afterwards
-               isWide = true;
-               codeStream.position += 4;
-               codeStream.classFileOffset += 4;
-       } else { //Position is set. Write it!
-               codeStream.writeSignedWord(position - codeStream.position + 1);
+
+       /**
+        * @param codeStream
+        *            net.sourceforge.phpdt.internal.compiler.codegen.CodeStream
+        */
+       // public Label(CodeStream codeStream) {
+       // this.codeStream = codeStream;
+       // }
+       /**
+        * Add a forward refrence for the array.
+        */
+       void addForwardReference(int iPos) {
+               int length;
+               if (forwardReferenceCount >= (length = forwardReferences.length))
+                       System.arraycopy(forwardReferences, 0,
+                                       (forwardReferences = new int[2 * length]), 0, length);
+               forwardReferences[forwardReferenceCount++] = iPos;
        }
-}
-/**
- * @return boolean
- */
-public boolean hasForwardReferences() {
-       return forwardReferenceCount != 0;
-}
-/*
- * Some placed labels might be branching to a goto bytecode which we can optimize better.
- */
-public void inlineForwardReferencesFromLabelsTargeting(int gotoLocation) {
-/*
- Code required to optimized unreachable gotos.
-       public boolean isBranchTarget(int location) {
-               Label[] labels = codeStream.labels;
-               for (int i = codeStream.countLabels - 1; i >= 0; i--){
-                       Label label = labels[i];
-                       if ((label.position == location) && label.isStandardLabel()){
-                               return true;
-                       }
+
+       /**
+        * Add a forward refrence for the array.
+        */
+       public void appendForwardReferencesFrom(Label otherLabel) {
+               int otherCount = otherLabel.forwardReferenceCount;
+               if (otherCount == 0)
+                       return;
+               int length = forwardReferences.length;
+               int neededSpace = otherCount + forwardReferenceCount;
+               if (neededSpace >= length) {
+                       System.arraycopy(forwardReferences, 0,
+                                       (forwardReferences = new int[neededSpace]), 0,
+                                       forwardReferenceCount);
                }
-               return false;
+               // append other forward references at the end, so they will get updated
+               // as well
+               System.arraycopy(otherLabel.forwardReferences, 0, forwardReferences,
+                               forwardReferenceCount, otherCount);
+               forwardReferenceCount = neededSpace;
        }
- */
-       
-       Label[] labels = codeStream.labels;
-       for (int i = codeStream.countLabels - 1; i >= 0; i--){
-               Label label = labels[i];
-               if ((label.position == gotoLocation) && label.isStandardLabel()){
-                       this.appendForwardReferencesFrom(label);
-                       /*
-                        Code required to optimized unreachable gotos.
-                               label.position = POS_NOT_SET;
-                       */
-               } else {
-                       break; // same target labels should be contiguous
-               }
+
+       /*
+        * Put down a refernece to the array at the location in the codestream.
+        */
+       // void branch() {
+       // if (position == POS_NOT_SET) {
+       // addForwardReference(codeStream.position);
+       // // Leave two bytes free to generate the jump afterwards
+       // codeStream.position += 2;
+       // codeStream.classFileOffset += 2;
+       // } else {
+       // /*
+       // * Position is set. Write it if it is not a wide branch.
+       // */
+       // int offset = position - codeStream.position + 1;
+       // if (Math.abs(offset) > 0x7FFF && !this.codeStream.wideMode) {
+       // throw new AbortMethod(CodeStream.RESTART_IN_WIDE_MODE);
+       // }
+       // codeStream.writeSignedShort((short) offset);
+       // }
+       // }
+       /*
+        * No support for wide branches yet
+        */
+       // void branchWide() {
+       // if (position == POS_NOT_SET) {
+       // addForwardReference(codeStream.position);
+       // // Leave 4 bytes free to generate the jump offset afterwards
+       // isWide = true;
+       // codeStream.position += 4;
+       // codeStream.classFileOffset += 4;
+       // } else { //Position is set. Write it!
+       // codeStream.writeSignedWord(position - codeStream.position + 1);
+       // }
+       // }
+       /**
+        * @return boolean
+        */
+       public boolean hasForwardReferences() {
+               return forwardReferenceCount != 0;
        }
-}
-public boolean isStandardLabel(){
-       return true;
-}
-/*
-* Place the label. If we have forward references resolve them.
-*/
-public void place() { // Currently lacking wide support.
-       if (position == POS_NOT_SET) {
-               position = codeStream.position;
-               codeStream.addLabel(this);
-               int oldPosition = position;
-               boolean optimizedBranch = false;
-               // TURNED OFF since fail on 1F4IRD9
-               if (forwardReferenceCount != 0) {
-                       if (optimizedBranch = (forwardReferences[forwardReferenceCount - 1] + 2 == position) && (codeStream.bCodeStream[codeStream.classFileOffset - 3] == CodeStream.OPC_goto)) {
-                               codeStream.position = (position -= 3);
-                               codeStream.classFileOffset -= 3;
-                               forwardReferenceCount--;
-                               // also update the PCs in the related debug attributes
-                               /** OLD CODE
-                                       int index = codeStream.pcToSourceMapSize - 1;
-                                               while ((index >= 0) && (codeStream.pcToSourceMap[index][1] == oldPosition)) {
-                                                       codeStream.pcToSourceMap[index--][1] = position;
-                                               }
-                               */
-                               // Beginning of new code
-                               int index = codeStream.pcToSourceMapSize - 2;
-                               if (codeStream.lastEntryPC == oldPosition) {
-                                       codeStream.lastEntryPC = position;
-                               }
-                               if ((index >= 0) && (codeStream.pcToSourceMap[index] == position)) {
-                                       codeStream.pcToSourceMapSize-=2;
-                               }
-                               // end of new code
-                               if (codeStream.generateLocalVariableTableAttributes) {
-                                       LocalVariableBinding locals[] = codeStream.locals;
-                                       for (int i = 0, max = locals.length; i < max; i++) {
-                                               LocalVariableBinding local = locals[i];
-                                               if ((local != null) && (local.initializationCount > 0)) {
-                                                       if (local.initializationPCs[((local.initializationCount - 1) << 1) + 1] == oldPosition) {
-                                                               // we want to prevent interval of size 0 to have a negative size.
-                                                               // see PR 1GIRQLA: ITPJCORE:ALL - ClassFormatError for local variable attribute
-                                                               local.initializationPCs[((local.initializationCount - 1) << 1) + 1] = position;
-                                                       }
-                                                       if (local.initializationPCs[(local.initializationCount - 1) << 1] == oldPosition) {
-                                                               local.initializationPCs[(local.initializationCount - 1) << 1] = position;
-                                                       }
-                                               }
-                                       }
-                               }
-                       }
-               }
-               for (int i = 0; i < forwardReferenceCount; i++) {
-                       int offset = position - forwardReferences[i] + 1;
-                       if (offset > 0x7FFF && !this.codeStream.wideMode) {
-                               throw new AbortMethod(CodeStream.RESTART_IN_WIDE_MODE);
-                       }
-                       if (this.codeStream.wideMode) {
-                               if (this.isWide) {
-                                       codeStream.writeSignedWord(forwardReferences[i], offset);
-                               } else {
-                                       codeStream.writeSignedShort(forwardReferences[i], (short) offset);
-                               }
-                       } else {
-                               codeStream.writeSignedShort(forwardReferences[i], (short) offset);
-                       }
-               }
-               // For all labels placed at that position we check if we need to rewrite the jump
-               // offset. It is the case each time a label had a forward reference to the current position.
-               // Like we change the current position, we have to change the jump offset. See 1F4IRD9 for more details.
-               if (optimizedBranch) {
-                       for (int i = 0; i < codeStream.countLabels; i++) {
-                               Label label = codeStream.labels[i];
-                               if (oldPosition == label.position) {
-                                       label.position = position;
-                                       if (label instanceof CaseLabel) {
-                                               int offset = position - ((CaseLabel) label).instructionPosition;
-                                               for (int j = 0; j < label.forwardReferenceCount; j++) {
-                                                       int forwardPosition = label.forwardReferences[j];
-                                                       codeStream.writeSignedWord(forwardPosition, offset);
-                                               }
-                                       } else {
-                                               for (int j = 0; j < label.forwardReferenceCount; j++) {
-                                                       int forwardPosition = label.forwardReferences[j];
-                                                       int offset = position - forwardPosition + 1;
-                                                       if (offset > 0x7FFF && !this.codeStream.wideMode) {
-                                                               throw new AbortMethod(CodeStream.RESTART_IN_WIDE_MODE);
-                                                       }
-                                                       if (this.codeStream.wideMode) {
-                                                               if (this.isWide) {
-                                                                       codeStream.writeSignedWord(forwardPosition, offset);
-                                                               } else {
-                                                                       codeStream.writeSignedShort(forwardPosition, (short) offset);
-                                                               }
-                                                       } else {
-                                                               codeStream.writeSignedShort(forwardPosition, (short) offset);
-                                                       }
-                                               }
-                                       }
-                               }
-                       }
-               }
+
+       /*
+        * Some placed labels might be branching to a goto bytecode which we can
+        * optimize better.
+        */
+       // public void inlineForwardReferencesFromLabelsTargeting(int gotoLocation)
+       // {
+       // /*
+       // Code required to optimized unreachable gotos.
+       // public boolean isBranchTarget(int location) {
+       // Label[] labels = codeStream.labels;
+       // for (int i = codeStream.countLabels - 1; i >= 0; i--){
+       // Label label = labels[i];
+       // if ((label.position == location) && label.isStandardLabel()){
+       // return true;
+       // }
+       // }
+       // return false;
+       // }
+       // */
+       //      
+       // Label[] labels = codeStream.labels;
+       // for (int i = codeStream.countLabels - 1; i >= 0; i--){
+       // Label label = labels[i];
+       // if ((label.position == gotoLocation) && label.isStandardLabel()){
+       // this.appendForwardReferencesFrom(label);
+       // /*
+       // Code required to optimized unreachable gotos.
+       // label.position = POS_NOT_SET;
+       // */
+       // } else {
+       // break; // same target labels should be contiguous
+       // }
+       // }
+       // }
+       public boolean isStandardLabel() {
+               return true;
        }
-}
-/**
- * Print out the receiver
- */
-public String toString() {
-       StringBuffer buffer = new StringBuffer("(position="); //$NON-NLS-1$
-       buffer.append(position);
-       buffer.append(", forwards = ["); //$NON-NLS-1$
-       for (int i = 0; i < forwardReferenceCount - 1; i++)
-               buffer.append(forwardReferences[i] + ", "); //$NON-NLS-1$
-       if (forwardReferenceCount >= 1)
-               buffer.append(forwardReferences[forwardReferenceCount-1]);
-       buffer.append("] )"); //$NON-NLS-1$
-       return buffer.toString();
-}
 
-public void resetStateForCodeGeneration() {
-       this.position = POS_NOT_SET;
-       this.forwardReferenceCount = 0;
-}
+       /*
+        * Place the label. If we have forward references resolve them.
+        */
+       // public void place() { // Currently lacking wide support.
+       // if (position == POS_NOT_SET) {
+       // position = codeStream.position;
+       // codeStream.addLabel(this);
+       // int oldPosition = position;
+       // boolean optimizedBranch = false;
+       // // TURNED OFF since fail on 1F4IRD9
+       // if (forwardReferenceCount != 0) {
+       // if (optimizedBranch = (forwardReferences[forwardReferenceCount - 1] + 2
+       // == position) && (codeStream.bCodeStream[codeStream.classFileOffset - 3]
+       // == CodeStream.OPC_goto)) {
+       // codeStream.position = (position -= 3);
+       // codeStream.classFileOffset -= 3;
+       // forwardReferenceCount--;
+       // // also update the PCs in the related debug attributes
+       // /** OLD CODE
+       // int index = codeStream.pcToSourceMapSize - 1;
+       // while ((index >= 0) && (codeStream.pcToSourceMap[index][1] ==
+       // oldPosition)) {
+       // codeStream.pcToSourceMap[index--][1] = position;
+       // }
+       // */
+       // // Beginning of new code
+       // int index = codeStream.pcToSourceMapSize - 2;
+       // if (codeStream.lastEntryPC == oldPosition) {
+       // codeStream.lastEntryPC = position;
+       // }
+       // if ((index >= 0) && (codeStream.pcToSourceMap[index] == position)) {
+       // codeStream.pcToSourceMapSize-=2;
+       // }
+       // // end of new code
+       // if (codeStream.generateLocalVariableTableAttributes) {
+       // LocalVariableBinding locals[] = codeStream.locals;
+       // for (int i = 0, max = locals.length; i < max; i++) {
+       // LocalVariableBinding local = locals[i];
+       // if ((local != null) && (local.initializationCount > 0)) {
+       // if (local.initializationPCs[((local.initializationCount - 1) << 1) + 1]
+       // == oldPosition) {
+       // // we want to prevent interval of size 0 to have a negative size.
+       // // see PR 1GIRQLA: ITPJCORE:ALL - ClassFormatError for local variable
+       // attribute
+       // local.initializationPCs[((local.initializationCount - 1) << 1) + 1] =
+       // position;
+       // }
+       // if (local.initializationPCs[(local.initializationCount - 1) << 1] ==
+       // oldPosition) {
+       // local.initializationPCs[(local.initializationCount - 1) << 1] = position;
+       // }
+       // }
+       // }
+       // }
+       // }
+       // }
+       // for (int i = 0; i < forwardReferenceCount; i++) {
+       // int offset = position - forwardReferences[i] + 1;
+       // if (Math.abs(offset) > 0x7FFF && !this.codeStream.wideMode) {
+       // throw new AbortMethod(CodeStream.RESTART_IN_WIDE_MODE);
+       // }
+       // if (this.codeStream.wideMode) {
+       // if (this.isWide) {
+       // codeStream.writeSignedWord(forwardReferences[i], offset);
+       // } else {
+       // codeStream.writeSignedShort(forwardReferences[i], (short) offset);
+       // }
+       // } else {
+       // codeStream.writeSignedShort(forwardReferences[i], (short) offset);
+       // }
+       // }
+       // // For all labels placed at that position we check if we need to rewrite
+       // the jump
+       // // offset. It is the case each time a label had a forward reference to
+       // the current position.
+       // // Like we change the current position, we have to change the jump
+       // offset. See 1F4IRD9 for more details.
+       // if (optimizedBranch) {
+       // for (int i = 0; i < codeStream.countLabels; i++) {
+       // Label label = codeStream.labels[i];
+       // if (oldPosition == label.position) {
+       // label.position = position;
+       // if (label instanceof CaseLabel) {
+       // int offset = position - ((CaseLabel) label).instructionPosition;
+       // for (int j = 0; j < label.forwardReferenceCount; j++) {
+       // int forwardPosition = label.forwardReferences[j];
+       // codeStream.writeSignedWord(forwardPosition, offset);
+       // }
+       // } else {
+       // for (int j = 0; j < label.forwardReferenceCount; j++) {
+       // int forwardPosition = label.forwardReferences[j];
+       // int offset = position - forwardPosition + 1;
+       // if (Math.abs(offset) > 0x7FFF && !this.codeStream.wideMode) {
+       // throw new AbortMethod(CodeStream.RESTART_IN_WIDE_MODE);
+       // }
+       // if (this.codeStream.wideMode) {
+       // if (this.isWide) {
+       // codeStream.writeSignedWord(forwardPosition, offset);
+       // } else {
+       // codeStream.writeSignedShort(forwardPosition, (short) offset);
+       // }
+       // } else {
+       // codeStream.writeSignedShort(forwardPosition, (short) offset);
+       // }
+       // }
+       // }
+       // }
+       // }
+       // }
+       // }
+       // }
+       /**
+        * Print out the receiver
+        */
+       public String toString() {
+               StringBuffer buffer = new StringBuffer("(position="); //$NON-NLS-1$
+               buffer.append(position);
+               buffer.append(", forwards = ["); //$NON-NLS-1$
+               for (int i = 0; i < forwardReferenceCount - 1; i++)
+                       buffer.append(forwardReferences[i] + ", "); //$NON-NLS-1$
+               if (forwardReferenceCount >= 1)
+                       buffer.append(forwardReferences[forwardReferenceCount - 1]);
+               buffer.append("] )"); //$NON-NLS-1$
+               return buffer.toString();
+       }
+
+       public void resetStateForCodeGeneration() {
+               this.position = POS_NOT_SET;
+               this.forwardReferenceCount = 0;
+       }
 }