--- a/jdk/src/java.base/share/classes/java/lang/invoke/DirectMethodHandle.java Thu Feb 05 14:57:53 2015 -0800
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/DirectMethodHandle.java Thu Feb 12 13:55:05 2015 -0800
@@ -31,7 +31,6 @@
import sun.invoke.util.VerifyAccess;
import static java.lang.invoke.MethodHandleNatives.Constants.*;
import static java.lang.invoke.LambdaForm.*;
-import static java.lang.invoke.LambdaForm.BasicType.*;
import static java.lang.invoke.MethodTypeForm.*;
import static java.lang.invoke.MethodHandleStatics.*;
import java.lang.ref.WeakReference;
@@ -693,4 +692,10 @@
}
}
}
+
+ @Override
+ void customize() {
+ assert(form.customized == null);
+ // No need to customize DMHs.
+ }
}
--- a/jdk/src/java.base/share/classes/java/lang/invoke/InvokerBytecodeGenerator.java Thu Feb 05 14:57:53 2015 -0800
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/InvokerBytecodeGenerator.java Thu Feb 12 13:55:05 2015 -0800
@@ -56,9 +56,11 @@
private static final String OBJ = "java/lang/Object";
private static final String OBJARY = "[Ljava/lang/Object;";
+ private static final String MH_SIG = "L" + MH + ";";
private static final String LF_SIG = "L" + LF + ";";
private static final String LFN_SIG = "L" + LFN + ";";
private static final String LL_SIG = "(L" + OBJ + ";)L" + OBJ + ";";
+ private static final String LLV_SIG = "(L" + OBJ + ";L" + OBJ + ";)V";
private static final String CLL_SIG = "(L" + CLS + ";L" + OBJ + ";)L" + OBJ + ";";
/** Name of its super class*/
@@ -616,6 +618,15 @@
return g.loadMethod(g.generateCustomizedCodeBytes());
}
+ /** Generates code to check that actual receiver and LambdaForm matches */
+ private boolean checkActualReceiver() {
+ // Expects MethodHandle on the stack and actual receiver MethodHandle in slot #0
+ mv.visitInsn(Opcodes.DUP);
+ mv.visitVarInsn(Opcodes.ALOAD, localsMap[0]);
+ mv.visitMethodInsn(Opcodes.INVOKESTATIC, MHI, "assertSame", LLV_SIG, false);
+ return true;
+ }
+
/**
* Generate an invoker method for the passed {@link LambdaForm}.
*/
@@ -635,6 +646,16 @@
mv.visitAnnotation("Ljava/lang/invoke/DontInline;", true);
}
+ if (lambdaForm.customized != null) {
+ // Since LambdaForm is customized for a particular MethodHandle, it's safe to substitute
+ // receiver MethodHandle (at slot #0) with an embedded constant and use it instead.
+ // It enables more efficient code generation in some situations, since embedded constants
+ // are compile-time constants for JIT compiler.
+ mv.visitLdcInsn(constantPlaceholder(lambdaForm.customized));
+ mv.visitTypeInsn(Opcodes.CHECKCAST, MH);
+ assert(checkActualReceiver()); // expects MethodHandle on top of the stack
+ mv.visitVarInsn(Opcodes.ASTORE, localsMap[0]);
+ }
// iterate over the form's names, generating bytecode instructions for each
// start iterating at the first name following the arguments
--- a/jdk/src/java.base/share/classes/java/lang/invoke/Invokers.java Thu Feb 05 14:57:53 2015 -0800
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/Invokers.java Thu Feb 12 13:55:05 2015 -0800
@@ -247,6 +247,7 @@
int nameCursor = OUTARG_LIMIT;
final int MTYPE_ARG = customized ? -1 : nameCursor++; // might be last in-argument
final int CHECK_TYPE = nameCursor++;
+ final int CHECK_CUSTOM = (CUSTOMIZE_THRESHOLD >= 0) ? nameCursor++ : -1;
final int LINKER_CALL = nameCursor++;
MethodType invokerFormType = mtype.invokerType();
if (isLinker) {
@@ -279,6 +280,9 @@
// mh.invokeGeneric(a*):R => checkGenericType(mh, TYPEOF(a*:R)).invokeBasic(a*)
outArgs[0] = names[CHECK_TYPE];
}
+ if (CHECK_CUSTOM != -1) {
+ names[CHECK_CUSTOM] = new Name(NF_checkCustomized, names[CALL_MH]);
+ }
names[LINKER_CALL] = new Name(outCallType, outArgs);
lform = new LambdaForm(debugName, INARG_LIMIT, names);
if (isLinker)
@@ -386,11 +390,32 @@
return ((CallSite)site).getTarget();
}
+ /*non-public*/ static
+ @ForceInline
+ void checkCustomized(Object o) {
+ MethodHandle mh = (MethodHandle)o;
+ if (mh.form.customized == null) {
+ maybeCustomize(mh);
+ }
+ }
+
+ /*non-public*/ static
+ @DontInline
+ void maybeCustomize(MethodHandle mh) {
+ byte count = mh.customizationCount;
+ if (count >= CUSTOMIZE_THRESHOLD) {
+ mh.customize();
+ } else {
+ mh.customizationCount = (byte)(count+1);
+ }
+ }
+
// Local constant functions:
private static final NamedFunction
NF_checkExactType,
NF_checkGenericType,
- NF_getCallSiteTarget;
+ NF_getCallSiteTarget,
+ NF_checkCustomized;
static {
try {
NamedFunction nfs[] = {
@@ -399,7 +424,9 @@
NF_checkGenericType = new NamedFunction(Invokers.class
.getDeclaredMethod("checkGenericType", Object.class, Object.class)),
NF_getCallSiteTarget = new NamedFunction(Invokers.class
- .getDeclaredMethod("getCallSiteTarget", Object.class))
+ .getDeclaredMethod("getCallSiteTarget", Object.class)),
+ NF_checkCustomized = new NamedFunction(Invokers.class
+ .getDeclaredMethod("checkCustomized", Object.class))
};
for (NamedFunction nf : nfs) {
// Each nf must be statically invocable or we get tied up in our bootstraps.
--- a/jdk/src/java.base/share/classes/java/lang/invoke/LambdaForm.java Thu Feb 05 14:57:53 2015 -0800
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/LambdaForm.java Thu Feb 12 13:55:05 2015 -0800
@@ -120,12 +120,14 @@
final int arity;
final int result;
final boolean forceInline;
+ final MethodHandle customized;
@Stable final Name[] names;
final String debugName;
MemberName vmentry; // low-level behavior, or null if not yet prepared
private boolean isCompiled;
- volatile Object transformCache; // managed by LambdaFormEditor
+ // Either a LambdaForm cache (managed by LambdaFormEditor) or a link to uncustomized version (for customized LF)
+ volatile Object transformCache;
public static final int VOID_RESULT = -1, LAST_RESULT = -2;
@@ -244,16 +246,17 @@
LambdaForm(String debugName,
int arity, Name[] names, int result) {
- this(debugName, arity, names, result, true);
+ this(debugName, arity, names, result, /*forceInline=*/true, /*customized=*/null);
}
LambdaForm(String debugName,
- int arity, Name[] names, int result, boolean forceInline) {
+ int arity, Name[] names, int result, boolean forceInline, MethodHandle customized) {
assert(namesOK(arity, names));
this.arity = arity;
this.result = fixResult(result, names);
this.names = names.clone();
this.debugName = fixDebugName(debugName);
this.forceInline = forceInline;
+ this.customized = customized;
int maxOutArity = normalize();
if (maxOutArity > MethodType.MAX_MH_INVOKER_ARITY) {
// Cannot use LF interpreter on very high arity expressions.
@@ -263,21 +266,21 @@
}
LambdaForm(String debugName,
int arity, Name[] names) {
- this(debugName, arity, names, LAST_RESULT, true);
+ this(debugName, arity, names, LAST_RESULT, /*forceInline=*/true, /*customized=*/null);
}
LambdaForm(String debugName,
int arity, Name[] names, boolean forceInline) {
- this(debugName, arity, names, LAST_RESULT, forceInline);
+ this(debugName, arity, names, LAST_RESULT, forceInline, /*customized=*/null);
}
LambdaForm(String debugName,
Name[] formals, Name[] temps, Name result) {
this(debugName,
- formals.length, buildNames(formals, temps, result), LAST_RESULT, true);
+ formals.length, buildNames(formals, temps, result), LAST_RESULT, /*forceInline=*/true, /*customized=*/null);
}
LambdaForm(String debugName,
Name[] formals, Name[] temps, Name result, boolean forceInline) {
this(debugName,
- formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline);
+ formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline, /*customized=*/null);
}
private static Name[] buildNames(Name[] formals, Name[] temps, Name result) {
@@ -291,10 +294,6 @@
}
private LambdaForm(String sig) {
- this(sig, true);
- }
-
- private LambdaForm(String sig, boolean forceInline) {
// Make a blank lambda form, which returns a constant zero or null.
// It is used as a template for managing the invocation of similar forms that are non-empty.
// Called only from getPreparedForm.
@@ -303,7 +302,8 @@
this.result = (signatureReturn(sig) == V_TYPE ? -1 : arity);
this.names = buildEmptyNames(arity, sig);
this.debugName = "LF.zero";
- this.forceInline = forceInline;
+ this.forceInline = true;
+ this.customized = null;
assert(nameRefsAreLegal());
assert(isEmpty());
assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature();
@@ -375,6 +375,31 @@
return true;
}
+ /** Customize LambdaForm for a particular MethodHandle */
+ LambdaForm customize(MethodHandle mh) {
+ LambdaForm customForm = new LambdaForm(debugName, arity, names, result, forceInline, mh);
+ if (COMPILE_THRESHOLD > 0 && isCompiled) {
+ // If shared LambdaForm has been compiled, compile customized version as well.
+ customForm.compileToBytecode();
+ }
+ customForm.transformCache = this; // LambdaFormEditor should always use uncustomized form.
+ return customForm;
+ }
+
+ /** Get uncustomized flavor of the LambdaForm */
+ LambdaForm uncustomize() {
+ if (customized == null) {
+ return this;
+ }
+ assert(transformCache != null); // Customized LambdaForm should always has a link to uncustomized version.
+ LambdaForm uncustomizedForm = (LambdaForm)transformCache;
+ if (COMPILE_THRESHOLD > 0 && isCompiled) {
+ // If customized LambdaForm has been compiled, compile uncustomized version as well.
+ uncustomizedForm.compileToBytecode();
+ }
+ return uncustomizedForm;
+ }
+
/** Renumber and/or replace params so that they are interned and canonically numbered.
* @return maximum argument list length among the names (since we have to pass over them anyway)
*/
@@ -417,8 +442,8 @@
for (int i = arity; i < names.length; i++) {
names[i].internArguments();
}
- assert(nameRefsAreLegal());
}
+ assert(nameRefsAreLegal());
return maxOutArity;
}
--- a/jdk/src/java.base/share/classes/java/lang/invoke/LambdaFormEditor.java Thu Feb 05 14:57:53 2015 -0800
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/LambdaFormEditor.java Thu Feb 12 13:55:05 2015 -0800
@@ -51,7 +51,10 @@
static LambdaFormEditor lambdaFormEditor(LambdaForm lambdaForm) {
// TO DO: Consider placing intern logic here, to cut down on duplication.
// lambdaForm = findPreexistingEquivalent(lambdaForm)
- return new LambdaFormEditor(lambdaForm);
+
+ // Always use uncustomized version for editing.
+ // It helps caching and customized LambdaForms reuse transformCache field to keep a link to uncustomized version.
+ return new LambdaFormEditor(lambdaForm.uncustomize());
}
/** A description of a cached transform, possibly associated with the result of the transform.
--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandle.java Thu Feb 05 14:57:53 2015 -0800
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandle.java Thu Feb 12 13:55:05 2015 -0800
@@ -434,6 +434,8 @@
// form is not private so that invokers can easily fetch it
/*private*/ MethodHandle asTypeCache;
// asTypeCache is not private so that invokers can easily fetch it
+ /*non-public*/ byte customizationCount;
+ // customizationCount should be accessible from invokers
/**
* Reports the type of this method handle.
@@ -454,9 +456,9 @@
type.getClass(); // explicit NPE
form.getClass(); // explicit NPE
this.type = type;
- this.form = form;
+ this.form = form.uncustomize();
- form.prepare(); // TO DO: Try to delay this step until just before invocation.
+ this.form.prepare(); // TO DO: Try to delay this step until just before invocation.
}
/**
@@ -1425,12 +1427,24 @@
*/
/*non-public*/
void updateForm(LambdaForm newForm) {
+ assert(newForm.customized == null || newForm.customized == this);
if (form == newForm) return;
newForm.prepare(); // as in MethodHandle.<init>
UNSAFE.putObject(this, FORM_OFFSET, newForm);
UNSAFE.fullFence();
}
+ /** Craft a LambdaForm customized for this particular MethodHandle */
+ /*non-public*/
+ void customize() {
+ if (form.customized == null) {
+ LambdaForm newForm = form.customize(this);
+ updateForm(newForm);
+ } else {
+ assert(form.customized == this);
+ }
+ }
+
private static final long FORM_OFFSET;
static {
try {
--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleImpl.java Thu Feb 05 14:57:53 2015 -0800
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleImpl.java Thu Feb 12 13:55:05 2015 -0800
@@ -597,6 +597,7 @@
static final NamedFunction NF_checkSpreadArgument;
static final NamedFunction NF_guardWithCatch;
static final NamedFunction NF_throwException;
+ static final NamedFunction NF_profileBoolean;
static final MethodHandle MH_castReference;
static final MethodHandle MH_selectAlternative;
@@ -614,10 +615,12 @@
NF_guardWithCatch = new NamedFunction(MHI.getDeclaredMethod("guardWithCatch", MethodHandle.class, Class.class,
MethodHandle.class, Object[].class));
NF_throwException = new NamedFunction(MHI.getDeclaredMethod("throwException", Throwable.class));
+ NF_profileBoolean = new NamedFunction(MHI.getDeclaredMethod("profileBoolean", boolean.class, int[].class));
NF_checkSpreadArgument.resolve();
NF_guardWithCatch.resolve();
NF_throwException.resolve();
+ NF_profileBoolean.resolve();
MH_castReference = IMPL_LOOKUP.findStatic(MHI, "castReference",
MethodType.methodType(Object.class, Class.class, Object.class));
@@ -697,7 +700,26 @@
@LambdaForm.Hidden
static
MethodHandle selectAlternative(boolean testResult, MethodHandle target, MethodHandle fallback) {
- return testResult ? target : fallback;
+ if (testResult) {
+ return target;
+ } else {
+ return fallback;
+ }
+ }
+
+ // Intrinsified by C2. Counters are used during parsing to calculate branch frequencies.
+ @LambdaForm.Hidden
+ static
+ boolean profileBoolean(boolean result, int[] counters) {
+ // Profile is int[2] where [0] and [1] correspond to false and true occurrences respectively.
+ int idx = result ? 1 : 0;
+ try {
+ counters[idx] = Math.addExact(counters[idx], 1);
+ } catch (ArithmeticException e) {
+ // Avoid continuous overflow by halving the problematic count.
+ counters[idx] = counters[idx] / 2;
+ }
+ return result;
}
static
@@ -708,13 +730,18 @@
assert(test.type().equals(type.changeReturnType(boolean.class)) && fallback.type().equals(type));
MethodType basicType = type.basicType();
LambdaForm form = makeGuardWithTestForm(basicType);
- BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLL();
BoundMethodHandle mh;
-
try {
- mh = (BoundMethodHandle)
- data.constructor().invokeBasic(type, form,
- (Object) test, (Object) profile(target), (Object) profile(fallback));
+ if (PROFILE_GWT) {
+ int[] counts = new int[2];
+ mh = (BoundMethodHandle)
+ BoundMethodHandle.speciesData_LLLL().constructor().invokeBasic(type, form,
+ (Object) test, (Object) profile(target), (Object) profile(fallback), counts);
+ } else {
+ mh = (BoundMethodHandle)
+ BoundMethodHandle.speciesData_LLL().constructor().invokeBasic(type, form,
+ (Object) test, (Object) profile(target), (Object) profile(fallback));
+ }
} catch (Throwable ex) {
throw uncaughtException(ex);
}
@@ -726,7 +753,7 @@
static
MethodHandle profile(MethodHandle target) {
if (DONT_INLINE_THRESHOLD >= 0) {
- return makeBlockInlningWrapper(target);
+ return makeBlockInliningWrapper(target);
} else {
return target;
}
@@ -737,8 +764,13 @@
* Corresponding LambdaForm has @DontInline when compiled into bytecode.
*/
static
- MethodHandle makeBlockInlningWrapper(MethodHandle target) {
- LambdaForm lform = PRODUCE_BLOCK_INLINING_FORM.apply(target);
+ MethodHandle makeBlockInliningWrapper(MethodHandle target) {
+ LambdaForm lform;
+ if (DONT_INLINE_THRESHOLD > 0) {
+ lform = PRODUCE_BLOCK_INLINING_FORM.apply(target);
+ } else {
+ lform = PRODUCE_REINVOKER_FORM.apply(target);
+ }
return new CountingWrapper(target, lform,
PRODUCE_BLOCK_INLINING_FORM, PRODUCE_REINVOKER_FORM,
DONT_INLINE_THRESHOLD);
@@ -800,7 +832,7 @@
MethodHandle wrapper;
if (isCounting) {
LambdaForm lform;
- lform = countingFormProducer.apply(target);
+ lform = countingFormProducer.apply(newTarget);
wrapper = new CountingWrapper(newTarget, lform, countingFormProducer, nonCountingFormProducer, DONT_INLINE_THRESHOLD);
} else {
wrapper = newTarget; // no need for a counting wrapper anymore
@@ -809,7 +841,8 @@
}
boolean countDown() {
- if (count <= 0) {
+ int c = count;
+ if (c <= 1) {
// Try to limit number of updates. MethodHandle.updateForm() doesn't guarantee LF update visibility.
if (isCounting) {
isCounting = false;
@@ -818,7 +851,7 @@
return false;
}
} else {
- --count;
+ count = c - 1;
return false;
}
}
@@ -856,7 +889,10 @@
final int GET_TEST = nameCursor++;
final int GET_TARGET = nameCursor++;
final int GET_FALLBACK = nameCursor++;
+ final int GET_COUNTERS = PROFILE_GWT ? nameCursor++ : -1;
final int CALL_TEST = nameCursor++;
+ final int PROFILE = (GET_COUNTERS != -1) ? nameCursor++ : -1;
+ final int TEST = nameCursor-1; // previous statement: either PROFILE or CALL_TEST
final int SELECT_ALT = nameCursor++;
final int CALL_TARGET = nameCursor++;
assert(CALL_TARGET == SELECT_ALT+1); // must be true to trigger IBG.emitSelectAlternative
@@ -864,12 +900,16 @@
MethodType lambdaType = basicType.invokerType();
Name[] names = arguments(nameCursor - ARG_LIMIT, lambdaType);
- BoundMethodHandle.SpeciesData data = BoundMethodHandle.speciesData_LLL();
+ BoundMethodHandle.SpeciesData data =
+ (GET_COUNTERS != -1) ? BoundMethodHandle.speciesData_LLLL()
+ : BoundMethodHandle.speciesData_LLL();
names[THIS_MH] = names[THIS_MH].withConstraint(data);
names[GET_TEST] = new Name(data.getterFunction(0), names[THIS_MH]);
names[GET_TARGET] = new Name(data.getterFunction(1), names[THIS_MH]);
names[GET_FALLBACK] = new Name(data.getterFunction(2), names[THIS_MH]);
-
+ if (GET_COUNTERS != -1) {
+ names[GET_COUNTERS] = new Name(data.getterFunction(3), names[THIS_MH]);
+ }
Object[] invokeArgs = Arrays.copyOfRange(names, 0, ARG_LIMIT, Object[].class);
// call test
@@ -877,15 +917,18 @@
invokeArgs[0] = names[GET_TEST];
names[CALL_TEST] = new Name(testType, invokeArgs);
+ // profile branch
+ if (PROFILE != -1) {
+ names[PROFILE] = new Name(Lazy.NF_profileBoolean, names[CALL_TEST], names[GET_COUNTERS]);
+ }
// call selectAlternative
- names[SELECT_ALT] = new Name(Lazy.MH_selectAlternative, names[CALL_TEST],
- names[GET_TARGET], names[GET_FALLBACK]);
+ names[SELECT_ALT] = new Name(Lazy.MH_selectAlternative, names[TEST], names[GET_TARGET], names[GET_FALLBACK]);
// call target or fallback
invokeArgs[0] = names[SELECT_ALT];
names[CALL_TARGET] = new Name(basicType, invokeArgs);
- lform = new LambdaForm("guard", lambdaType.parameterCount(), names);
+ lform = new LambdaForm("guard", lambdaType.parameterCount(), names, /*forceInline=*/true);
return basicType.form().setCachedLambdaForm(MethodTypeForm.LF_GWT, lform);
}
@@ -1629,4 +1672,13 @@
assert(elemType.isPrimitive());
return Lazy.MH_copyAsPrimitiveArray.bindTo(Wrapper.forPrimitiveType(elemType));
}
+
+ /*non-public*/ static void assertSame(Object mh1, Object mh2) {
+ if (mh1 != mh2) {
+ String msg = String.format("mh1 != mh2: mh1 = %s (form: %s); mh2 = %s (form: %s)",
+ mh1, ((MethodHandle)mh1).form,
+ mh2, ((MethodHandle)mh2).form);
+ throw newInternalError(msg);
+ }
+ }
}
--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleStatics.java Thu Feb 05 14:57:53 2015 -0800
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandleStatics.java Thu Feb 12 13:55:05 2015 -0800
@@ -48,9 +48,11 @@
static final int COMPILE_THRESHOLD;
static final int DONT_INLINE_THRESHOLD;
static final int PROFILE_LEVEL;
+ static final boolean PROFILE_GWT;
+ static final int CUSTOMIZE_THRESHOLD;
static {
- final Object[] values = new Object[7];
+ final Object[] values = new Object[9];
AccessController.doPrivileged(new PrivilegedAction<Void>() {
public Void run() {
values[0] = Boolean.getBoolean("java.lang.invoke.MethodHandle.DEBUG_NAMES");
@@ -60,6 +62,8 @@
values[4] = Integer.getInteger("java.lang.invoke.MethodHandle.COMPILE_THRESHOLD", 0);
values[5] = Integer.getInteger("java.lang.invoke.MethodHandle.DONT_INLINE_THRESHOLD", 30);
values[6] = Integer.getInteger("java.lang.invoke.MethodHandle.PROFILE_LEVEL", 0);
+ values[7] = Boolean.parseBoolean(System.getProperty("java.lang.invoke.MethodHandle.PROFILE_GWT", "true"));
+ values[8] = Integer.getInteger("java.lang.invoke.MethodHandle.CUSTOMIZE_THRESHOLD", 127);
return null;
}
});
@@ -70,6 +74,12 @@
COMPILE_THRESHOLD = (Integer) values[4];
DONT_INLINE_THRESHOLD = (Integer) values[5];
PROFILE_LEVEL = (Integer) values[6];
+ PROFILE_GWT = (Boolean) values[7];
+ CUSTOMIZE_THRESHOLD = (Integer) values[8];
+
+ if (CUSTOMIZE_THRESHOLD < -1 || CUSTOMIZE_THRESHOLD > 127) {
+ throw newInternalError("CUSTOMIZE_THRESHOLD should be in [-1...127] range");
+ }
}
/** Tell if any of the debugging switches are turned on.