diff --git a/src/share/classes/java/lang/invoke/DirectMethodHandle.java b/src/share/classes/java/lang/invoke/DirectMethodHandle.java index e9d2526cd8d336b9f082065973f4345ff7d57278..fe54fd21492d08a633ed47d74d96d62354abadbd 100644 --- a/src/share/classes/java/lang/invoke/DirectMethodHandle.java +++ b/src/share/classes/java/lang/invoke/DirectMethodHandle.java @@ -31,7 +31,6 @@ import java.util.Arrays; 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 @@ class DirectMethodHandle extends MethodHandle { } } } + + @Override + void customize() { + assert(form.customized == null); + // No need to customize DMHs. + } } diff --git a/src/share/classes/java/lang/invoke/InvokerBytecodeGenerator.java b/src/share/classes/java/lang/invoke/InvokerBytecodeGenerator.java index 85988c70f80092e9fe8125669c59840c483bc9f6..d9c6f0ffbdfdb2954672a47248522cfad8cc4ab1 100644 --- a/src/share/classes/java/lang/invoke/InvokerBytecodeGenerator.java +++ b/src/share/classes/java/lang/invoke/InvokerBytecodeGenerator.java @@ -56,9 +56,11 @@ class InvokerBytecodeGenerator { 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 @@ class InvokerBytecodeGenerator { 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 +646,17 @@ class InvokerBytecodeGenerator { 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 Name onStack = null; diff --git a/src/share/classes/java/lang/invoke/Invokers.java b/src/share/classes/java/lang/invoke/Invokers.java index 14aef1bd7b46284b2209727dca4c511dcbd82fb0..e09dc3686c4fecce346a9e2f1716add5a1e105b0 100644 --- a/src/share/classes/java/lang/invoke/Invokers.java +++ b/src/share/classes/java/lang/invoke/Invokers.java @@ -247,6 +247,7 @@ class Invokers { 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 @@ class Invokers { // 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 @@ class Invokers { 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 @@ class Invokers { 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. diff --git a/src/share/classes/java/lang/invoke/LambdaForm.java b/src/share/classes/java/lang/invoke/LambdaForm.java index 7533d83bb25f9c5e07a9eb4336cbb097c54a92a3..5c441071b922302039b034c518d26d46153bdccc 100644 --- a/src/share/classes/java/lang/invoke/LambdaForm.java +++ b/src/share/classes/java/lang/invoke/LambdaForm.java @@ -120,12 +120,14 @@ class LambdaForm { 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 @@ class LambdaForm { LambdaForm(String debugName, int arity, Name[] names, int result) { - this(debugName, arity, names, result, /*forceInline=*/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 @@ class LambdaForm { } LambdaForm(String debugName, int arity, Name[] names) { - this(debugName, arity, names, LAST_RESULT, /*forceInline=*/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, /*forceInline=*/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) { @@ -300,6 +303,7 @@ class LambdaForm { this.names = buildEmptyNames(arity, sig); this.debugName = "LF.zero"; this.forceInline = true; + this.customized = null; assert(nameRefsAreLegal()); assert(isEmpty()); assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature(); @@ -371,6 +375,31 @@ class LambdaForm { 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) */ @@ -413,8 +442,8 @@ class LambdaForm { for (int i = arity; i < names.length; i++) { names[i].internArguments(); } - assert(nameRefsAreLegal()); } + assert(nameRefsAreLegal()); return maxOutArity; } diff --git a/src/share/classes/java/lang/invoke/LambdaFormEditor.java b/src/share/classes/java/lang/invoke/LambdaFormEditor.java index 1c23e94995ac7c5818741fe40c6a9cfa27bfa4de..7bc2dfbebade51557bb3269c61c5580e88b1f7c4 100644 --- a/src/share/classes/java/lang/invoke/LambdaFormEditor.java +++ b/src/share/classes/java/lang/invoke/LambdaFormEditor.java @@ -51,7 +51,10 @@ class LambdaFormEditor { 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. diff --git a/src/share/classes/java/lang/invoke/MethodHandle.java b/src/share/classes/java/lang/invoke/MethodHandle.java index 9b586a3179cce393c3fd09c23c07f1782f2e9816..79730644a232729a99b673e536ab50db780fd326 100644 --- a/src/share/classes/java/lang/invoke/MethodHandle.java +++ b/src/share/classes/java/lang/invoke/MethodHandle.java @@ -434,6 +434,8 @@ public abstract class MethodHandle { // 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 @@ public abstract class MethodHandle { 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 @@ assertEquals("[three, thee, tee]", asListFix.invoke((Object)argv).toString()); */ /*non-public*/ void updateForm(LambdaForm newForm) { + assert(newForm.customized == null || newForm.customized == this); if (form == newForm) return; newForm.prepare(); // as in MethodHandle. 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 { diff --git a/src/share/classes/java/lang/invoke/MethodHandleImpl.java b/src/share/classes/java/lang/invoke/MethodHandleImpl.java index e15f03072360feb9fe901a137b33a6102e786b82..50b991fb2b374e6c41ba3c6e1848dd84b717408e 100644 --- a/src/share/classes/java/lang/invoke/MethodHandleImpl.java +++ b/src/share/classes/java/lang/invoke/MethodHandleImpl.java @@ -1652,4 +1652,13 @@ import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP; 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); + } + } } diff --git a/src/share/classes/java/lang/invoke/MethodHandleStatics.java b/src/share/classes/java/lang/invoke/MethodHandleStatics.java index 40b4397c1782b5c06674c8a7c55e1765d14b73f7..144de11094f858b0ad8788575f689fd45daa566f 100644 --- a/src/share/classes/java/lang/invoke/MethodHandleStatics.java +++ b/src/share/classes/java/lang/invoke/MethodHandleStatics.java @@ -49,9 +49,10 @@ import sun.misc.Unsafe; 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[8]; + final Object[] values = new Object[9]; AccessController.doPrivileged(new PrivilegedAction() { public Void run() { values[0] = Boolean.getBoolean("java.lang.invoke.MethodHandle.DEBUG_NAMES"); @@ -62,6 +63,7 @@ import sun.misc.Unsafe; 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; } }); @@ -73,6 +75,11 @@ import sun.misc.Unsafe; 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.