split MIC from PIC

This commit is contained in:
Robert Muir 2016-06-15 09:07:11 -04:00
parent 2b1ebc55a9
commit b71f42a627
2 changed files with 156 additions and 83 deletions

View File

@ -78,6 +78,12 @@ public final class DefBootstrap {
*/
public static final int OPERATOR_ALLOWS_NULL = 1 << 0;
/**
* static bootstrap parameter indicating the binary operator is part of compound assignment (e.g. +=).
*
*/
public static final int OPERATOR_COMPOUND_ASSIGNMENT = 1 << 1;
/**
* CallSite that implements the polymorphic inlining cache (PIC).
*/
@ -98,13 +104,7 @@ public final class DefBootstrap {
this.flavor = flavor;
this.args = args;
// For operators use a monomorphic cache, fallback is fast.
// Just start with a depth of MAX-1, to keep it a constant.
if (flavor == UNARY_OPERATOR || flavor == BINARY_OPERATOR || flavor == SHIFT_OPERATOR) {
depth = MAX_DEPTH - 1;
}
final MethodHandle fallback = FALLBACK.bindTo(this)
MethodHandle fallback = FALLBACK.bindTo(this)
.asCollector(Object[].class, type.parameterCount())
.asType(type);
@ -119,22 +119,6 @@ public final class DefBootstrap {
return receiver.getClass() == clazz;
}
/**
* guard method for inline caching: checks the receiver's class and the first argument
* are the same as the cached receiver and first argument.
*/
static boolean checkBinary(Class<?> left, Class<?> right, Object leftObject, Object rightObject) {
return leftObject.getClass() == left && rightObject.getClass() == right;
}
/**
* guard method for inline caching: checks the first argument is the same
* as the cached first argument.
*/
static boolean checkBinaryArg(Class<?> left, Class<?> right, Object leftObject, Object rightObject) {
return rightObject.getClass() == right;
}
/**
* Does a slow lookup against the whitelist.
*/
@ -154,34 +138,10 @@ public final class DefBootstrap {
return Def.lookupIterator(args[0].getClass());
case REFERENCE:
return Def.lookupReference(lookup, (String) this.args[0], args[0].getClass(), name);
case UNARY_OPERATOR:
case SHIFT_OPERATOR:
// shifts are treated as unary, as java allows long arguments without a cast (but bits are ignored)
return DefMath.lookupUnary(args[0].getClass(), name);
case BINARY_OPERATOR:
if (args[0] == null || args[1] == null) {
return getGeneric(flavor, name); // can handle nulls, if supported
} else {
return DefMath.lookupBinary(args[0].getClass(), args[1].getClass(), name);
}
default: throw new AssertionError();
}
}
/**
* Installs a permanent, generic solution that works with any parameter types, if possible.
*/
private MethodHandle getGeneric(int flavor, String name) throws Throwable {
switch(flavor) {
case UNARY_OPERATOR:
case BINARY_OPERATOR:
case SHIFT_OPERATOR:
return DefMath.lookupGeneric(name);
default:
return null;
}
}
/**
* Called when a new type is encountered (or, when we have encountered more than {@code MAX_DEPTH}
* types at this call site and given up on caching).
@ -189,14 +149,92 @@ public final class DefBootstrap {
@SuppressForbidden(reason = "slow path")
Object fallback(Object[] args) throws Throwable {
if (depth >= MAX_DEPTH) {
// caching defeated
MethodHandle generic = getGeneric(flavor, name);
if (generic != null) {
setTarget(generic.asType(type()));
return generic.invokeWithArguments(args);
} else {
// XXX: caching defeated: lookups up every time(!)
return lookup(flavor, name, args).invokeWithArguments(args);
}
final MethodType type = type();
final MethodHandle target = lookup(flavor, name, args).asType(type);
MethodHandle test = CHECK_CLASS.bindTo(args[0].getClass());
test = test.asType(test.type().changeParameterType(0, type.parameterType(0)));
MethodHandle guard = MethodHandles.guardWithTest(test, target, getTarget());
depth++;
setTarget(guard);
return target.invokeWithArguments(args);
}
private static final MethodHandle CHECK_CLASS;
private static final MethodHandle FALLBACK;
static {
final Lookup lookup = MethodHandles.lookup();
try {
CHECK_CLASS = lookup.findStatic(lookup.lookupClass(), "checkClass",
MethodType.methodType(boolean.class, Class.class, Object.class));
FALLBACK = lookup.findVirtual(lookup.lookupClass(), "fallback",
MethodType.methodType(Object.class, Object[].class));
} catch (ReflectiveOperationException e) {
throw new AssertionError(e);
}
}
}
/**
* CallSite that implements the monomorphic inlining cache (for operators).
*/
static final class MIC extends MutableCallSite {
private boolean initialized;
private final String name;
private final int flavor;
private final int flags;
MIC(String name, MethodType type, int flavor, int flags) {
super(type);
this.name = name;
this.flavor = flavor;
this.flags = flags;
MethodHandle fallback = FALLBACK.bindTo(this)
.asCollector(Object[].class, type.parameterCount())
.asType(type);
setTarget(fallback);
}
/**
* Does a slow lookup for the operator
*/
private MethodHandle lookup(int flavor, String name, Object[] args) throws Throwable {
switch(flavor) {
case UNARY_OPERATOR:
case SHIFT_OPERATOR:
// shifts are treated as unary, as java allows long arguments without a cast (but bits are ignored)
return DefMath.lookupUnary(args[0].getClass(), name);
case BINARY_OPERATOR:
if (args[0] == null || args[1] == null) {
return DefMath.lookupGeneric(name); // can handle nulls, if supported
} else {
return DefMath.lookupBinary(args[0].getClass(), args[1].getClass(), name);
}
default: throw new AssertionError();
}
}
/**
* Called when a new type is encountered (or, when we have encountered more than {@code MAX_DEPTH}
* types at this call site and given up on caching).
*/
@SuppressForbidden(reason = "slow path")
Object fallback(Object[] args) throws Throwable {
if (initialized) {
// caching defeated
MethodHandle generic = DefMath.lookupGeneric(name);
setTarget(generic.asType(type()));
return generic.invokeWithArguments(args);
}
final MethodType type = type();
@ -209,24 +247,25 @@ public final class DefBootstrap {
Class<?> clazz1 = args[1] == null ? null : args[1].getClass();
if (type.parameterType(1) != Object.class) {
// case 1: only the receiver is unknown, just check that
MethodHandle unaryTest = CHECK_CLASS.bindTo(clazz0);
MethodHandle unaryTest = CHECK_LHS.bindTo(clazz0);
test = unaryTest.asType(unaryTest.type()
.changeParameterType(0, type.parameterType(0)));
} else if (type.parameterType(0) != Object.class) {
// case 2: only the argument is unknown, just check that
MethodHandle unaryTest = CHECK_BINARY_ARG.bindTo(clazz0).bindTo(clazz1);
MethodHandle unaryTest = CHECK_RHS.bindTo(clazz0).bindTo(clazz1);
test = unaryTest.asType(unaryTest.type()
.changeParameterType(0, type.parameterType(0))
.changeParameterType(1, type.parameterType(1)));
} else {
// case 3: check both receiver and argument
MethodHandle binaryTest = CHECK_BINARY.bindTo(clazz0).bindTo(clazz1);
MethodHandle binaryTest = CHECK_BOTH.bindTo(clazz0).bindTo(clazz1);
test = binaryTest.asType(binaryTest.type()
.changeParameterType(0, type.parameterType(0))
.changeParameterType(1, type.parameterType(1)));
}
} else {
MethodHandle receiverTest = CHECK_CLASS.bindTo(args[0].getClass());
// unary operator
MethodHandle receiverTest = CHECK_LHS.bindTo(args[0].getClass());
test = receiverTest.asType(receiverTest.type()
.changeParameterType(0, type.parameterType(0)));
}
@ -234,29 +273,56 @@ public final class DefBootstrap {
MethodHandle guard = MethodHandles.guardWithTest(test, target, getTarget());
// very special cases, where even the receiver can be null (see JLS rules for string concat)
// we wrap + with an NPE catcher, and use our generic method in that case.
if (flavor == BINARY_OPERATOR && ((int)this.args[0] & OPERATOR_ALLOWS_NULL) != 0) {
MethodHandle handler = MethodHandles.dropArguments(getGeneric(flavor, name).asType(type()), 0, NullPointerException.class);
if (flavor == BINARY_OPERATOR && (flags & OPERATOR_ALLOWS_NULL) != 0) {
MethodHandle handler = MethodHandles.dropArguments(DefMath.lookupGeneric(name).asType(type()),
0,
NullPointerException.class);
guard = MethodHandles.catchException(guard, NullPointerException.class, handler);
}
depth++;
initialized = true;
setTarget(guard);
return target.invokeWithArguments(args);
}
private static final MethodHandle CHECK_CLASS;
private static final MethodHandle CHECK_BINARY;
private static final MethodHandle CHECK_BINARY_ARG;
/**
* guard method for inline caching: checks the receiver's class is the same
* as the cached class
*/
static boolean checkLHS(Class<?> clazz, Object leftObject) {
return leftObject.getClass() == clazz;
}
/**
* guard method for inline caching: checks the first argument is the same
* as the cached first argument.
*/
static boolean checkRHS(Class<?> left, Class<?> right, Object leftObject, Object rightObject) {
return rightObject.getClass() == right;
}
/**
* guard method for inline caching: checks the receiver's class and the first argument
* are the same as the cached receiver and first argument.
*/
static boolean checkBoth(Class<?> left, Class<?> right, Object leftObject, Object rightObject) {
return leftObject.getClass() == left && rightObject.getClass() == right;
}
private static final MethodHandle CHECK_LHS;
private static final MethodHandle CHECK_RHS;
private static final MethodHandle CHECK_BOTH;
private static final MethodHandle FALLBACK;
static {
final Lookup lookup = MethodHandles.lookup();
try {
CHECK_CLASS = lookup.findStatic(lookup.lookupClass(), "checkClass",
CHECK_LHS = lookup.findStatic(lookup.lookupClass(), "checkLHS",
MethodType.methodType(boolean.class, Class.class, Object.class));
CHECK_BINARY = lookup.findStatic(lookup.lookupClass(), "checkBinary",
CHECK_RHS = lookup.findStatic(lookup.lookupClass(), "checkRHS",
MethodType.methodType(boolean.class, Class.class, Class.class, Object.class, Object.class));
CHECK_BINARY_ARG = lookup.findStatic(lookup.lookupClass(), "checkBinaryArg",
CHECK_BOTH = lookup.findStatic(lookup.lookupClass(), "checkBoth",
MethodType.methodType(boolean.class, Class.class, Class.class, Object.class, Object.class));
FALLBACK = lookup.findVirtual(lookup.lookupClass(), "fallback",
MethodType.methodType(Object.class, Object[].class));
@ -277,6 +343,7 @@ public final class DefBootstrap {
public static CallSite bootstrap(Lookup lookup, String name, MethodType type, int flavor, Object... args) {
// validate arguments
switch(flavor) {
// "function-call" like things get a polymorphic cache
case METHOD_CALL:
if (args.length != 1) {
throw new BootstrapMethodError("Invalid number of parameters for method call");
@ -288,7 +355,16 @@ public final class DefBootstrap {
if (Long.bitCount(recipe) > type.parameterCount()) {
throw new BootstrapMethodError("Illegal recipe for method call: too many bits");
}
break;
return new PIC(lookup, name, type, flavor, args);
case LOAD:
case STORE:
case ARRAY_LOAD:
case ARRAY_STORE:
case ITERATOR:
if (args.length > 0) {
throw new BootstrapMethodError("Illegal static bootstrap parameters for flavor: " + flavor);
}
return new PIC(lookup, name, type, flavor, args);
case REFERENCE:
if (args.length != 1) {
throw new BootstrapMethodError("Invalid number of parameters for reference call");
@ -296,7 +372,9 @@ public final class DefBootstrap {
if (args[0] instanceof String == false) {
throw new BootstrapMethodError("Illegal parameter for reference call: " + args[0]);
}
break;
return new PIC(lookup, name, type, flavor, args);
// operators get monomorphic cache, with a generic impl for a fallback
case UNARY_OPERATOR:
case SHIFT_OPERATOR:
case BINARY_OPERATOR:
@ -311,14 +389,9 @@ public final class DefBootstrap {
// we just don't need it anywhere else.
throw new BootstrapMethodError("This parameter is only supported for BINARY_OPERATORs");
}
break;
return new MIC(name, type, flavor, flags);
default:
if (args.length > 0) {
throw new BootstrapMethodError("Illegal static bootstrap parameters for flavor: " + flavor);
throw new BootstrapMethodError("Illegal static bootstrap parameter for flavor: " + flavor);
}
break;
}
return new PIC(lookup, name, type, flavor, args);
}
}

View File

@ -107,7 +107,7 @@ public class DefBootstrapTests extends ESTestCase {
// test operators with null guards
public void testNullGuardAdd() throws Throwable {
DefBootstrap.PIC site = (DefBootstrap.PIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
DefBootstrap.MIC site = (DefBootstrap.MIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
"add",
MethodType.methodType(Object.class, Object.class, Object.class),
DefBootstrap.BINARY_OPERATOR, DefBootstrap.OPERATOR_ALLOWS_NULL);
@ -116,7 +116,7 @@ public class DefBootstrapTests extends ESTestCase {
}
public void testNullGuardAddWhenCached() throws Throwable {
DefBootstrap.PIC site = (DefBootstrap.PIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
DefBootstrap.MIC site = (DefBootstrap.MIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
"add",
MethodType.methodType(Object.class, Object.class, Object.class),
DefBootstrap.BINARY_OPERATOR, DefBootstrap.OPERATOR_ALLOWS_NULL);
@ -126,7 +126,7 @@ public class DefBootstrapTests extends ESTestCase {
}
public void testNullGuardEq() throws Throwable {
DefBootstrap.PIC site = (DefBootstrap.PIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
DefBootstrap.MIC site = (DefBootstrap.MIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
"eq",
MethodType.methodType(boolean.class, Object.class, Object.class),
DefBootstrap.BINARY_OPERATOR, DefBootstrap.OPERATOR_ALLOWS_NULL);
@ -136,7 +136,7 @@ public class DefBootstrapTests extends ESTestCase {
}
public void testNullGuardEqWhenCached() throws Throwable {
DefBootstrap.PIC site = (DefBootstrap.PIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
DefBootstrap.MIC site = (DefBootstrap.MIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
"eq",
MethodType.methodType(boolean.class, Object.class, Object.class),
DefBootstrap.BINARY_OPERATOR, DefBootstrap.OPERATOR_ALLOWS_NULL);
@ -151,7 +151,7 @@ public class DefBootstrapTests extends ESTestCase {
// and can be disabled in some circumstances.
public void testNoNullGuardAdd() throws Throwable {
DefBootstrap.PIC site = (DefBootstrap.PIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
DefBootstrap.MIC site = (DefBootstrap.MIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
"add",
MethodType.methodType(Object.class, int.class, Object.class),
DefBootstrap.BINARY_OPERATOR, 0);
@ -162,7 +162,7 @@ public class DefBootstrapTests extends ESTestCase {
}
public void testNoNullGuardAddWhenCached() throws Throwable {
DefBootstrap.PIC site = (DefBootstrap.PIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
DefBootstrap.MIC site = (DefBootstrap.MIC) DefBootstrap.bootstrap(MethodHandles.publicLookup(),
"add",
MethodType.methodType(Object.class, int.class, Object.class),
DefBootstrap.BINARY_OPERATOR, 0);