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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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