--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Wed Sep 10 19:19:52 2014 +0400
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Wed Sep 10 19:19:52 2014 +0400
@@ -28,7 +28,6 @@
import java.lang.reflect.*;
import java.util.BitSet;
import java.util.List;
-import java.util.ArrayList;
import java.util.Arrays;
import sun.invoke.util.ValueConversions;
@@ -2094,23 +2093,86 @@
*/
public static
MethodHandle permuteArguments(MethodHandle target, MethodType newType, int... reorder) {
- reorder = reorder.clone();
- permuteArgumentChecks(reorder, newType, target.type());
- // first detect dropped arguments and handle them separately
- MethodHandle originalTarget = target;
- int newArity = newType.parameterCount();
- for (int dropIdx; (dropIdx = findFirstDrop(reorder, newArity)) >= 0; ) {
- // dropIdx is missing from reorder; add it in at the end
- int oldArity = reorder.length;
- target = dropArguments(target, oldArity, newType.parameterType(dropIdx));
- reorder = Arrays.copyOf(reorder, oldArity+1);
- reorder[oldArity] = dropIdx;
+ reorder = reorder.clone(); // get a private copy
+ MethodType oldType = target.type();
+ permuteArgumentChecks(reorder, newType, oldType);
+ if (USE_LAMBDA_FORM_EDITOR) {
+ // first detect dropped arguments and handle them separately
+ int[] originalReorder = reorder;
+ BoundMethodHandle result = target.rebind();
+ LambdaForm form = result.form;
+ int newArity = newType.parameterCount();
+ // Normalize the reordering into a real permutation,
+ // by removing duplicates and adding dropped elements.
+ // This somewhat improves lambda form caching, as well
+ // as simplifying the transform by breaking it up into steps.
+ for (int ddIdx; (ddIdx = findFirstDupOrDrop(reorder, newArity)) != 0; ) {
+ if (ddIdx > 0) {
+ // We found a duplicated entry at reorder[ddIdx].
+ // Example: (x,y,z)->asList(x,y,z)
+ // permuted by [1*,0,1] => (a0,a1)=>asList(a1,a0,a1)
+ // permuted by [0,1,0*] => (a0,a1)=>asList(a0,a1,a0)
+ // The starred element corresponds to the argument
+ // deleted by the dupArgumentForm transform.
+ int srcPos = ddIdx, dstPos = srcPos, dupVal = reorder[srcPos];
+ boolean killFirst = false;
+ for (int val; (val = reorder[--dstPos]) != dupVal; ) {
+ // Set killFirst if the dup is larger than an intervening position.
+ // This will remove at least one inversion from the permutation.
+ if (dupVal > val) killFirst = true;
+ }
+ if (!killFirst) {
+ srcPos = dstPos;
+ dstPos = ddIdx;
+ }
+ form = form.editor().dupArgumentForm(1 + srcPos, 1 + dstPos);
+ assert (reorder[srcPos] == reorder[dstPos]);
+ oldType = oldType.dropParameterTypes(dstPos, dstPos + 1);
+ // contract the reordering by removing the element at dstPos
+ int tailPos = dstPos + 1;
+ System.arraycopy(reorder, tailPos, reorder, dstPos, reorder.length - tailPos);
+ reorder = Arrays.copyOf(reorder, reorder.length - 1);
+ } else {
+ int dropVal = ~ddIdx, insPos = 0;
+ while (insPos < reorder.length && reorder[insPos] < dropVal) {
+ // Find first element of reorder larger than dropVal.
+ // This is where we will insert the dropVal.
+ insPos += 1;
+ }
+ Class<?> ptype = newType.parameterType(dropVal);
+ form = form.editor().addArgumentForm(1 + insPos, BasicType.basicType(ptype));
+ oldType = oldType.insertParameterTypes(insPos, ptype);
+ // expand the reordering by inserting an element at insPos
+ int tailPos = insPos + 1;
+ reorder = Arrays.copyOf(reorder, reorder.length + 1);
+ System.arraycopy(reorder, insPos, reorder, tailPos, reorder.length - tailPos);
+ reorder[insPos] = dropVal;
+ }
+ assert (permuteArgumentChecks(reorder, newType, oldType));
+ }
+ assert (reorder.length == newArity); // a perfect permutation
+ // Note: This may cache too many distinct LFs. Consider backing off to varargs code.
+ form = form.editor().permuteArgumentsForm(1, reorder);
+ if (newType == result.type() && form == result.internalForm())
+ return result;
+ return result.copyWith(newType, form);
+ } else {
+ // first detect dropped arguments and handle them separately
+ MethodHandle originalTarget = target;
+ int newArity = newType.parameterCount();
+ for (int dropIdx; (dropIdx = findFirstDrop(reorder, newArity)) >= 0; ) {
+ // dropIdx is missing from reorder; add it in at the end
+ int oldArity = reorder.length;
+ target = dropArguments(target, oldArity, newType.parameterType(dropIdx));
+ reorder = Arrays.copyOf(reorder, oldArity+1);
+ reorder[oldArity] = dropIdx;
+ }
+ assert(target == originalTarget || permuteArgumentChecks(reorder, newType, target.type()));
+ // Note: This may cache too many distinct LFs. Consider backing off to varargs code.
+ BoundMethodHandle result = target.rebind();
+ LambdaForm form = result.form.permuteArguments(1, reorder, basicTypes(newType.parameterList()));
+ return result.copyWith(newType, form);
}
- assert(target == originalTarget || permuteArgumentChecks(reorder, newType, target.type()));
- // Note: This may cache too many distinct LFs. Consider backing off to varargs code.
- BoundMethodHandle result = target.rebind();
- LambdaForm form = result.form.permuteArguments(1, reorder, basicTypes(newType.parameterList()));
- return result.copyWith(newType, form);
}
/** Return the first value in [0..newArity-1] that is not present in reorder. */
@@ -2143,6 +2205,52 @@
return zeroPos;
}
+ /**
+ * Return an indication of any duplicate or omission in reorder.
+ * If the reorder contains a duplicate entry, return the index of the second occurrence.
+ * Otherwise, return ~(n), for the first n in [0..newArity-1] that is not present in reorder.
+ * Otherwise, return zero.
+ * If an element not in [0..newArity-1] is encountered, return reorder.length.
+ */
+ private static int findFirstDupOrDrop(int[] reorder, int newArity) {
+ final int BIT_LIMIT = 63; // max number of bits in bit mask
+ if (newArity < BIT_LIMIT) {
+ long mask = 0;
+ for (int i = 0; i < reorder.length; i++) {
+ int arg = reorder[i];
+ if (arg >= newArity) return reorder.length;
+ int bit = 1 << arg;
+ if ((mask & bit) != 0)
+ return i; // >0 indicates a dup
+ mask |= bit;
+ }
+ if (mask == (1 << newArity) - 1) {
+ assert(Long.numberOfTrailingZeros(Long.lowestOneBit(~mask)) == newArity);
+ return 0;
+ }
+ // find first zero
+ long zeroBit = Long.lowestOneBit(~mask);
+ int zeroPos = Long.numberOfTrailingZeros(zeroBit);
+ assert(zeroPos < newArity);
+ return ~zeroPos;
+ } else {
+ // same algorithm, different bit set
+ BitSet mask = new BitSet(newArity);
+ for (int i = 0; i < reorder.length; i++) {
+ int arg = reorder[i];
+ if (arg >= newArity) return reorder.length;
+ if (mask.get(arg))
+ return i; // >0 indicates a dup
+ mask.set(arg);
+ }
+ int zeroPos = mask.nextClearBit(0);
+ if (zeroPos == newArity) {
+ return 0;
+ }
+ return ~zeroPos;
+ }
+ }
+
private static boolean permuteArgumentChecks(int[] reorder, MethodType newType, MethodType oldType) {
if (newType.returnType() != oldType.returnType())
throw newIllegalArgumentException("return types do not match",
@@ -2374,7 +2482,14 @@
if (dropped == 0) return target;
BoundMethodHandle result = target.rebind();
LambdaForm lform = result.form;
- lform = lform.addArguments(pos, valueTypes);
+ if (USE_LAMBDA_FORM_EDITOR) {
+ int insertFormArg = 1 + pos;
+ for (Class<?> ptype : valueTypes) {
+ lform = lform.editor().addArgumentForm(insertFormArg++, BasicType.basicType(ptype));
+ }
+ } else {
+ lform = lform.addArguments(pos, valueTypes);
+ }
MethodType newType = oldType.insertParameterTypes(pos, valueTypes);
result = result.copyWith(newType, lform);
return result;
@@ -2525,7 +2640,18 @@
/*non-public*/ static
MethodHandle filterArgument(MethodHandle target, int pos, MethodHandle filter) {
filterArgumentChecks(target, pos, filter);
- return MethodHandleImpl.makeCollectArguments(target, filter, pos, false);
+ if (USE_LAMBDA_FORM_EDITOR) {
+ MethodType targetType = target.type();
+ MethodType filterType = filter.type();
+ BoundMethodHandle result = target.rebind();
+ Class<?> newParamType = filterType.parameterType(0);
+ LambdaForm lform = result.editor().filterArgumentForm(1 + pos, BasicType.basicType(newParamType));
+ MethodType newType = targetType.changeParameterType(pos, newParamType);
+ result = result.copyWithExtendL(newType, lform, filter);
+ return result;
+ } else {
+ return MethodHandleImpl.makeCollectArguments(target, filter, pos, false);
+ }
}
private static void filterArgumentsCheckArity(MethodHandle target, int pos, MethodHandle[] filters) {
@@ -2651,12 +2777,36 @@
*/
public static
MethodHandle collectArguments(MethodHandle target, int pos, MethodHandle filter) {
+ MethodType newType = collectArgumentsChecks(target, pos, filter);
+ if (USE_LAMBDA_FORM_EDITOR) {
+ MethodType collectorType = filter.type();
+ BoundMethodHandle result = target.rebind();
+ LambdaForm lform;
+ if (collectorType.returnType().isArray() && filter.intrinsicName() == Intrinsic.NEW_ARRAY) {
+ lform = result.editor().collectArgumentArrayForm(1 + pos, filter);
+ if (lform != null) {
+ return result.copyWith(newType, lform);
+ }
+ }
+ lform = result.editor().collectArgumentsForm(1 + pos, collectorType.basicType());
+ return result.copyWithExtendL(newType, lform, filter);
+ } else {
+ return MethodHandleImpl.makeCollectArguments(target, filter, pos, false);
+ }
+ }
+
+ private static MethodType collectArgumentsChecks(MethodHandle target, int pos, MethodHandle filter) throws RuntimeException {
MethodType targetType = target.type();
MethodType filterType = filter.type();
- if (filterType.returnType() != void.class &&
- filterType.returnType() != targetType.parameterType(pos))
+ Class<?> rtype = filterType.returnType();
+ List<Class<?>> filterArgs = filterType.parameterList();
+ if (rtype == void.class) {
+ return targetType.insertParameterTypes(pos, filterArgs);
+ }
+ if (rtype != targetType.parameterType(pos)) {
throw newIllegalArgumentException("target and filter types do not match", targetType, filterType);
- return MethodHandleImpl.makeCollectArguments(target, filter, pos, false);
+ }
+ return targetType.dropParameterTypes(pos, pos+1).insertParameterTypes(pos, filterArgs);
}
/**
@@ -2721,7 +2871,16 @@
MethodType targetType = target.type();
MethodType filterType = filter.type();
filterReturnValueChecks(targetType, filterType);
- return MethodHandleImpl.makeCollectArguments(filter, target, 0, false);
+ if (USE_LAMBDA_FORM_EDITOR) {
+ BoundMethodHandle result = target.rebind();
+ BasicType rtype = BasicType.basicType(filterType.returnType());
+ LambdaForm lform = result.editor().filterReturnForm(rtype, false);
+ MethodType newType = targetType.changeReturnType(filterType.returnType());
+ result = result.copyWithExtendL(newType, lform, filter);
+ return result;
+ } else {
+ return MethodHandleImpl.makeCollectArguments(filter, target, 0, false);
+ }
}
private static void filterReturnValueChecks(MethodType targetType, MethodType filterType) throws RuntimeException {
@@ -2815,7 +2974,19 @@
MethodType targetType = target.type();
MethodType combinerType = combiner.type();
Class<?> rtype = foldArgumentChecks(foldPos, targetType, combinerType);
- return MethodHandleImpl.makeCollectArguments(target, combiner, foldPos, true);
+ if (USE_LAMBDA_FORM_EDITOR) {
+ BoundMethodHandle result = target.rebind();
+ boolean dropResult = (rtype == void.class);
+ // Note: This may cache too many distinct LFs. Consider backing off to varargs code.
+ LambdaForm lform = result.editor().foldArgumentsForm(1 + foldPos, dropResult, combinerType.basicType());
+ MethodType newType = targetType;
+ if (!dropResult)
+ newType = newType.dropParameterTypes(foldPos, foldPos + 1);
+ result = result.copyWithExtendL(newType, lform, combiner);
+ return result;
+ } else {
+ return MethodHandleImpl.makeCollectArguments(target, combiner, foldPos, true);
+ }
}
private static Class<?> foldArgumentChecks(int foldPos, MethodType targetType, MethodType combinerType) {