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src/java.xml/share/classes/com/sun/org/apache/bcel/internal/generic/SWITCH.java

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*** 19,42 **** * limitations under the License. */ package com.sun.org.apache.bcel.internal.generic; - /** * SWITCH - Branch depending on int value, generates either LOOKUPSWITCH or * TABLESWITCH instruction, depending on whether the match values (int[]) can be * sorted with no gaps between the numbers. * ! * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A> */ public final class SWITCH implements CompoundInstruction { private int[] match; private InstructionHandle[] targets; private Select instruction; private int match_length; /** * Template for switch() constructs. If the match array can be * sorted in ascending order with gaps no larger than max_gap * between the numbers, a TABLESWITCH instruction is generated, and * a LOOKUPSWITCH otherwise. The former may be more efficient, but --- 19,43 ---- * limitations under the License. */ package com.sun.org.apache.bcel.internal.generic; /** * SWITCH - Branch depending on int value, generates either LOOKUPSWITCH or * TABLESWITCH instruction, depending on whether the match values (int[]) can be * sorted with no gaps between the numbers. * ! * @version $Id: SWITCH.java 1749603 2016-06-21 20:50:19Z ggregory $ */ public final class SWITCH implements CompoundInstruction { + private int[] match; private InstructionHandle[] targets; private Select instruction; private int match_length; + /** * Template for switch() constructs. If the match array can be * sorted in ascending order with gaps no larger than max_gap * between the numbers, a TABLESWITCH instruction is generated, and * a LOOKUPSWITCH otherwise. The former may be more efficient, but
*** 48,150 **** * @param match array of match values (case 2: ... case 7: ..., etc.) * @param targets the instructions to be branched to for each case * @param target the default target * @param max_gap maximum gap that may between case branches */ ! public SWITCH(int[] match, InstructionHandle[] targets, ! InstructionHandle target, int max_gap) { ! this.match = (int[])match.clone(); ! this.targets = (InstructionHandle[])targets.clone(); ! ! if((match_length = match.length) < 2) // (almost) empty switch, or just default instruction = new TABLESWITCH(match, targets, target); ! else { sort(0, match_length - 1); ! ! if(matchIsOrdered(max_gap)) { fillup(max_gap, target); - instruction = new TABLESWITCH(this.match, this.targets, target); ! } ! else instruction = new LOOKUPSWITCH(this.match, this.targets, target); } } ! public SWITCH(int[] match, InstructionHandle[] targets, ! InstructionHandle target) { this(match, targets, target, 1); } - private final void fillup(int max_gap, InstructionHandle target) { - int max_size = match_length + match_length * max_gap; - int[] m_vec = new int[max_size]; - InstructionHandle[] t_vec = new InstructionHandle[max_size]; - int count = 1; m_vec[0] = match[0]; t_vec[0] = targets[0]; ! ! for(int i=1; i < match_length; i++) { ! int prev = match[i-1]; ! int gap = match[i] - prev; ! ! for(int j=1; j < gap; j++) { m_vec[count] = prev + j; t_vec[count] = target; count++; } - m_vec[count] = match[i]; t_vec[count] = targets[i]; count++; } - match = new int[count]; targets = new InstructionHandle[count]; - System.arraycopy(m_vec, 0, match, 0, count); System.arraycopy(t_vec, 0, targets, 0, count); } /** * Sort match and targets array with QuickSort. */ ! private final void sort(int l, int r) { ! int i = l, j = r; ! int h, m = match[(l + r) / 2]; InstructionHandle h2; - do { ! while(match[i] < m) i++; ! while(m < match[j]) j--; ! ! if(i <= j) { ! h=match[i]; match[i]=match[j]; match[j]=h; // Swap elements ! h2=targets[i]; targets[i]=targets[j]; targets[j]=h2; // Swap instructions, too ! i++; j--; } ! } while(i <= j); ! ! if(l < j) sort(l, j); ! if(i < r) sort(i, r); } /** * @return match is sorted in ascending order with no gap bigger than max_gap? */ ! private final boolean matchIsOrdered(int max_gap) { ! for(int i=1; i < match_length; i++) ! if(match[i] - match[i-1] > max_gap) return false; ! return true; } public final InstructionList getInstructionList() { return new InstructionList(instruction); } public final Instruction getInstruction() { return instruction; } } --- 49,160 ---- * @param match array of match values (case 2: ... case 7: ..., etc.) * @param targets the instructions to be branched to for each case * @param target the default target * @param max_gap maximum gap that may between case branches */ ! public SWITCH(final int[] match, final InstructionHandle[] targets, final InstructionHandle target, final int max_gap) { ! this.match = match.clone(); ! this.targets = targets.clone(); ! if ((match_length = match.length) < 2) { instruction = new TABLESWITCH(match, targets, target); ! } else { sort(0, match_length - 1); ! if (matchIsOrdered(max_gap)) { fillup(max_gap, target); instruction = new TABLESWITCH(this.match, this.targets, target); ! } else { instruction = new LOOKUPSWITCH(this.match, this.targets, target); } } + } ! ! public SWITCH(final int[] match, final InstructionHandle[] targets, final InstructionHandle target) { this(match, targets, target, 1); } + private void fillup( final int max_gap, final InstructionHandle target ) { + final int max_size = match_length + match_length * max_gap; + final int[] m_vec = new int[max_size]; + final InstructionHandle[] t_vec = new InstructionHandle[max_size]; + int count = 1; m_vec[0] = match[0]; t_vec[0] = targets[0]; ! for (int i = 1; i < match_length; i++) { ! final int prev = match[i - 1]; ! final int gap = match[i] - prev; ! for (int j = 1; j < gap; j++) { m_vec[count] = prev + j; t_vec[count] = target; count++; } m_vec[count] = match[i]; t_vec[count] = targets[i]; count++; } match = new int[count]; targets = new InstructionHandle[count]; System.arraycopy(m_vec, 0, match, 0, count); System.arraycopy(t_vec, 0, targets, 0, count); } + /** * Sort match and targets array with QuickSort. */ ! private void sort( final int l, final int r ) { ! int i = l; ! int j = r; ! int h; ! final int m = match[(l + r) / 2]; InstructionHandle h2; do { ! while (match[i] < m) { ! i++; } ! while (m < match[j]) { ! j--; ! } ! if (i <= j) { ! h = match[i]; ! match[i] = match[j]; ! match[j] = h; // Swap elements ! h2 = targets[i]; ! targets[i] = targets[j]; ! targets[j] = h2; // Swap instructions, too ! i++; ! j--; ! } ! } while (i <= j); ! if (l < j) { ! sort(l, j); ! } ! if (i < r) { ! sort(i, r); } + } + /** * @return match is sorted in ascending order with no gap bigger than max_gap? */ ! private boolean matchIsOrdered( final int max_gap ) { ! for (int i = 1; i < match_length; i++) { ! if (match[i] - match[i - 1] > max_gap) { return false; ! } ! } return true; } + + @Override public final InstructionList getInstructionList() { return new InstructionList(instruction); } + public final Instruction getInstruction() { return instruction; } }
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