JDK8/Java8源码在线阅读
/*
* Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package java.lang.invoke;
import java.lang.annotation.*;
import java.lang.reflect.Method;
import java.util.List;
import java.util.Arrays;
import java.util.HashMap;
import sun.invoke.util.Wrapper;
import java.lang.reflect.Field;
import static java.lang.invoke.LambdaForm.BasicType.*;
import static java.lang.invoke.MethodHandleStatics.*;
import static java.lang.invoke.MethodHandleNatives.Constants.*;
/**
* The symbolic, non-executable form of a method handle's invocation semantics.
* It consists of a series of names.
* The first N (N=arity) names are parameters,
* while any remaining names are temporary values.
* Each temporary specifies the application of a function to some arguments.
* The functions are method handles, while the arguments are mixes of
* constant values and local names.
* The result of the lambda is defined as one of the names, often the last one.
* <p>
* Here is an approximate grammar:
* <blockquote><pre>{@code
* LambdaForm = "(" ArgName* ")=>{" TempName* Result "}"
* ArgName = "a" N ":" T
* TempName = "t" N ":" T "=" Function "(" Argument* ");"
* Function = ConstantValue
* Argument = NameRef | ConstantValue
* Result = NameRef | "void"
* NameRef = "a" N | "t" N
* N = (any whole number)
* T = "L" | "I" | "J" | "F" | "D" | "V"
* }</pre></blockquote>
* Names are numbered consecutively from left to right starting at zero.
* (The letters are merely a taste of syntax sugar.)
* Thus, the first temporary (if any) is always numbered N (where N=arity).
* Every occurrence of a name reference in an argument list must refer to
* a name previously defined within the same lambda.
* A lambda has a void result if and only if its result index is -1.
* If a temporary has the type "V", it cannot be the subject of a NameRef,
* even though possesses a number.
* Note that all reference types are erased to "L", which stands for {@code Object}.
* All subword types (boolean, byte, short, char) are erased to "I" which is {@code int}.
* The other types stand for the usual primitive types.
* <p>
* Function invocation closely follows the static rules of the Java verifier.
* Arguments and return values must exactly match when their "Name" types are
* considered.
* Conversions are allowed only if they do not change the erased type.
* <ul>
* <li>L = Object: casts are used freely to convert into and out of reference types
* <li>I = int: subword types are forcibly narrowed when passed as arguments (see {@code explicitCastArguments})
* <li>J = long: no implicit conversions
* <li>F = float: no implicit conversions
* <li>D = double: no implicit conversions
* <li>V = void: a function result may be void if and only if its Name is of type "V"
* </ul>
* Although implicit conversions are not allowed, explicit ones can easily be
* encoded by using temporary expressions which call type-transformed identity functions.
* <p>
* Examples:
* <blockquote><pre>{@code
* (a0:J)=>{ a0 }
* == identity(long)
* (a0:I)=>{ t1:V = System.out#println(a0); void }
* == System.out#println(int)
* (a0:L)=>{ t1:V = System.out#println(a0); a0 }
* == identity, with printing side-effect
* (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0);
* t3:L = BoundMethodHandle#target(a0);
* t4:L = MethodHandle#invoke(t3, t2, a1); t4 }
* == general invoker for unary insertArgument combination
* (a0:L, a1:L)=>{ t2:L = FilterMethodHandle#filter(a0);
* t3:L = MethodHandle#invoke(t2, a1);
* t4:L = FilterMethodHandle#target(a0);
* t5:L = MethodHandle#invoke(t4, t3); t5 }
* == general invoker for unary filterArgument combination
* (a0:L, a1:L)=>{ ...(same as previous example)...
* t5:L = MethodHandle#invoke(t4, t3, a1); t5 }
* == general invoker for unary/unary foldArgument combination
* (a0:L, a1:I)=>{ t2:I = identity(long).asType((int)->long)(a1); t2 }
* == invoker for identity method handle which performs i2l
* (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0);
* t3:L = Class#cast(t2,a1); t3 }
* == invoker for identity method handle which performs cast
* }</pre></blockquote>
* <p>
* @author John Rose, JSR 292 EG
*/
class LambdaForm {
final int arity;
final int result;
final boolean forceInline;
@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
public static final int VOID_RESULT = -1, LAST_RESULT = -2;
enum BasicType {
L_TYPE('L', Object.class, Wrapper.OBJECT), // all reference types
I_TYPE('I', int.class, Wrapper.INT),
J_TYPE('J', long.class, Wrapper.LONG),
F_TYPE('F', float.class, Wrapper.FLOAT),
D_TYPE('D', double.class, Wrapper.DOUBLE), // all primitive types
V_TYPE('V', void.class, Wrapper.VOID); // not valid in all contexts
static final BasicType[] ALL_TYPES = BasicType.values();
static final BasicType[] ARG_TYPES = Arrays.copyOf(ALL_TYPES, ALL_TYPES.length-1);
static final int ARG_TYPE_LIMIT = ARG_TYPES.length;
static final int TYPE_LIMIT = ALL_TYPES.length;
private final char btChar;
private final Class<?> btClass;
private final Wrapper btWrapper;
private BasicType(char btChar, Class<?> btClass, Wrapper wrapper) {
this.btChar = btChar;
this.btClass = btClass;
this.btWrapper = wrapper;
}
char basicTypeChar() {
return btChar;
}
Class<?> basicTypeClass() {
return btClass;
}
Wrapper basicTypeWrapper() {
return btWrapper;
}
int basicTypeSlots() {
return btWrapper.stackSlots();
}
static BasicType basicType(byte type) {
return ALL_TYPES[type];
}
static BasicType basicType(char type) {
switch (type) {
case 'L': return L_TYPE;
case 'I': return I_TYPE;
case 'J': return J_TYPE;
case 'F': return F_TYPE;
case 'D': return D_TYPE;
case 'V': return V_TYPE;
// all subword types are represented as ints
case 'Z':
case 'B':
case 'S':
case 'C':
return I_TYPE;
default:
throw newInternalError("Unknown type char: '"+type+"'");
}
}
static BasicType basicType(Wrapper type) {
char c = type.basicTypeChar();
return basicType(c);
}
static BasicType basicType(Class<?> type) {
if (!type.isPrimitive()) return L_TYPE;
return basicType(Wrapper.forPrimitiveType(type));
}
static char basicTypeChar(Class<?> type) {
return basicType(type).btChar;
}
static BasicType[] basicTypes(List<Class<?>> types) {
BasicType[] btypes = new BasicType[types.size()];
for (int i = 0; i < btypes.length; i++) {
btypes[i] = basicType(types.get(i));
}
return btypes;
}
static BasicType[] basicTypes(String types) {
BasicType[] btypes = new BasicType[types.length()];
for (int i = 0; i < btypes.length; i++) {
btypes[i] = basicType(types.charAt(i));
}
return btypes;
}
static byte[] basicTypesOrd(BasicType[] btypes) {
byte[] ords = new byte[btypes.length];
for (int i = 0; i < btypes.length; i++) {
ords[i] = (byte)btypes[i].ordinal();
}
return ords;
}
static boolean isBasicTypeChar(char c) {
return "LIJFDV".indexOf(c) >= 0;
}
static boolean isArgBasicTypeChar(char c) {
return "LIJFD".indexOf(c) >= 0;
}
static { assert(checkBasicType()); }
private static boolean checkBasicType() {
for (int i = 0; i < ARG_TYPE_LIMIT; i++) {
assert ARG_TYPES[i].ordinal() == i;
assert ARG_TYPES[i] == ALL_TYPES[i];
}
for (int i = 0; i < TYPE_LIMIT; i++) {
assert ALL_TYPES[i].ordinal() == i;
}
assert ALL_TYPES[TYPE_LIMIT - 1] == V_TYPE;
assert !Arrays.asList(ARG_TYPES).contains(V_TYPE);
return true;
}
}
LambdaForm(String debugName,
int arity, Name[] names, int result) {
this(debugName, arity, names, result, true);
}
LambdaForm(String debugName,
int arity, Name[] names, int result, boolean forceInline) {
assert(namesOK(arity, names));
this.arity = arity;
this.result = fixResult(result, names);
this.names = names.clone();
this.debugName = fixDebugName(debugName);
this.forceInline = forceInline;
int maxOutArity = normalize();
if (maxOutArity > MethodType.MAX_MH_INVOKER_ARITY) {
// Cannot use LF interpreter on very high arity expressions.
assert(maxOutArity <= MethodType.MAX_JVM_ARITY);
compileToBytecode();
}
}
LambdaForm(String debugName,
int arity, Name[] names) {
this(debugName, arity, names, LAST_RESULT, true);
}
LambdaForm(String debugName,
int arity, Name[] names, boolean forceInline) {
this(debugName, arity, names, LAST_RESULT, forceInline);
}
LambdaForm(String debugName,
Name[] formals, Name[] temps, Name result) {
this(debugName,
formals.length, buildNames(formals, temps, result), LAST_RESULT, true);
}
LambdaForm(String debugName,
Name[] formals, Name[] temps, Name result, boolean forceInline) {
this(debugName,
formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline);
}
private static Name[] buildNames(Name[] formals, Name[] temps, Name result) {
int arity = formals.length;
int length = arity + temps.length + (result == null ? 0 : 1);
Name[] names = Arrays.copyOf(formals, length);
System.arraycopy(temps, 0, names, arity, temps.length);
if (result != null)
names[length - 1] = result;
return names;
}
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.
assert(isValidSignature(sig));
this.arity = signatureArity(sig);
this.result = (signatureReturn(sig) == V_TYPE ? -1 : arity);
this.names = buildEmptyNames(arity, sig);
this.debugName = "LF.zero";
this.forceInline = forceInline;
assert(nameRefsAreLegal());
assert(isEmpty());
assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature();
}
private static Name[] buildEmptyNames(int arity, String basicTypeSignature) {
assert(isValidSignature(basicTypeSignature));
int resultPos = arity + 1; // skip '_'
if (arity < 0 || basicTypeSignature.length() != resultPos+1)
throw new IllegalArgumentException("bad arity for "+basicTypeSignature);
int numRes = (basicType(basicTypeSignature.charAt(resultPos)) == V_TYPE ? 0 : 1);
Name[] names = arguments(numRes, basicTypeSignature.substring(0, arity));
for (int i = 0; i < numRes; i++) {
Name zero = new Name(constantZero(basicType(basicTypeSignature.charAt(resultPos + i))));
names[arity + i] = zero.newIndex(arity + i);
}
return names;
}
private static int fixResult(int result, Name[] names) {
if (result == LAST_RESULT)
result = names.length - 1; // might still be void
if (result >= 0 && names[result].type == V_TYPE)
result = VOID_RESULT;
return result;
}
private static String fixDebugName(String debugName) {
if (DEBUG_NAME_COUNTERS != null) {
int under = debugName.indexOf('_');
int length = debugName.length();
if (under < 0) under = length;
String debugNameStem = debugName.substring(0, under);
Integer ctr;
synchronized (DEBUG_NAME_COUNTERS) {
ctr = DEBUG_NAME_COUNTERS.get(debugNameStem);
if (ctr == null) ctr = 0;
DEBUG_NAME_COUNTERS.put(debugNameStem, ctr+1);
}
StringBuilder buf = new StringBuilder(debugNameStem);
buf.append('_');
int leadingZero = buf.length();
buf.append((int) ctr);
for (int i = buf.length() - leadingZero; i < 3; i++)
buf.insert(leadingZero, '0');
if (under < length) {
++under; // skip "_"
while (under < length && Character.isDigit(debugName.charAt(under))) {
++under;
}
if (under < length && debugName.charAt(under) == '_') ++under;
if (under < length)
buf.append('_').append(debugName, under, length);
}
return buf.toString();
}
return debugName;
}
private static boolean namesOK(int arity, Name[] names) {
for (int i = 0; i < names.length; i++) {
Name n = names[i];
assert(n != null) : "n is null";
if (i < arity)
assert( n.isParam()) : n + " is not param at " + i;
else
assert(!n.isParam()) : n + " is param at " + i;
}
return true;
}
/** 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)
*/
private int normalize() {
Name[] oldNames = null;
int maxOutArity = 0;
int changesStart = 0;
for (int i = 0; i < names.length; i++) {
Name n = names[i];
if (!n.initIndex(i)) {
if (oldNames == null) {
oldNames = names.clone();
changesStart = i;
}
names[i] = n.cloneWithIndex(i);
}
if (n.arguments != null && maxOutArity < n.arguments.length)
maxOutArity = n.arguments.length;
}
if (oldNames != null) {
int startFixing = arity;
if (startFixing <= changesStart)
startFixing = changesStart+1;
for (int i = startFixing; i < names.length; i++) {
Name fixed = names[i].replaceNames(oldNames, names, changesStart, i);
names[i] = fixed.newIndex(i);
}
}
assert(nameRefsAreLegal());
int maxInterned = Math.min(arity, INTERNED_ARGUMENT_LIMIT);
boolean needIntern = false;
for (int i = 0; i < maxInterned; i++) {
Name n = names[i], n2 = internArgument(n);
if (n != n2) {
names[i] = n2;
needIntern = true;
}
}
if (needIntern) {
for (int i = arity; i < names.length; i++) {
names[i].internArguments();
}
assert(nameRefsAreLegal());
}
return maxOutArity;
}
/**
* Check that all embedded Name references are localizable to this lambda,
* and are properly ordered after their corresponding definitions.
* <p>
* Note that a Name can be local to multiple lambdas, as long as
* it possesses the same index in each use site.
* This allows Name references to be freely reused to construct
* fresh lambdas, without confusion.
*/
boolean nameRefsAreLegal() {
assert(arity >= 0 && arity <= names.length);
assert(result >= -1 && result < names.length);
// Do all names possess an index consistent with their local definition order?
for (int i = 0; i < arity; i++) {
Name n = names[i];
assert(n.index() == i) : Arrays.asList(n.index(), i);
assert(n.isParam());
}
// Also, do all local name references
for (int i = arity; i < names.length; i++) {
Name n = names[i];
assert(n.index() == i);
for (Object arg : n.arguments) {
if (arg instanceof Name) {
Name n2 = (Name) arg;
int i2 = n2.index;
assert(0 <= i2 && i2 < names.length) : n.debugString() + ": 0 <= i2 && i2 < names.length: 0 <= " + i2 + " < " + names.length;
assert(names[i2] == n2) : Arrays.asList("-1-", i, "-2-", n.debugString(), "-3-", i2, "-4-", n2.debugString(), "-5-", names[i2].debugString(), "-6-", this);
assert(i2 < i); // ref must come after def!
}
}
}
return true;
}
/** Invoke this form on the given arguments. */
// final Object invoke(Object... args) throws Throwable {
// // NYI: fit this into the fast path?
// return interpretWithArguments(args);
// }
/** Report the return type. */
BasicType returnType() {
if (result < 0) return V_TYPE;
Name n = names[result];
return n.type;
}
/** Report the N-th argument type. */
BasicType parameterType(int n) {
return parameter(n).type;
}
/** Report the N-th argument name. */
Name parameter(int n) {
assert(n < arity);
Name param = names[n];
assert(param.isParam());
return param;
}
/** Report the N-th argument type constraint. */
Object parameterConstraint(int n) {
return parameter(n).constraint;
}
/** Report the arity. */
int arity() {
return arity;
}
/** Report the number of expressions (non-parameter names). */
int expressionCount() {
return names.length - arity;
}
/** Return the method type corresponding to my basic type signature. */
MethodType methodType() {
return signatureType(basicTypeSignature());
}
/** Return ABC_Z, where the ABC are parameter type characters, and Z is the return type character. */
final String basicTypeSignature() {
StringBuilder buf = new StringBuilder(arity() + 3);
for (int i = 0, a = arity(); i < a; i++)
buf.append(parameterType(i).basicTypeChar());
return buf.append('_').append(returnType().basicTypeChar()).toString();
}
static int signatureArity(String sig) {
assert(isValidSignature(sig));
return sig.indexOf('_');
}
static BasicType signatureReturn(String sig) {
return basicType(sig.charAt(signatureArity(sig) + 1));
}
static boolean isValidSignature(String sig) {
int arity = sig.indexOf('_');
if (arity < 0) return false; // must be of the form *_*
int siglen = sig.length();
if (siglen != arity + 2) return false; // *_X
for (int i = 0; i < siglen; i++) {
if (i == arity) continue; // skip '_'
char c = sig.charAt(i);
if (c == 'V')
return (i == siglen - 1 && arity == siglen - 2);
if (!isArgBasicTypeChar(c)) return false; // must be [LIJFD]
}
return true; // [LIJFD]*_[LIJFDV]
}
static MethodType signatureType(String sig) {
Class<?>[] ptypes = new Class<?>[signatureArity(sig)];
for (int i = 0; i < ptypes.length; i++)
ptypes[i] = basicType(sig.charAt(i)).btClass;
Class<?> rtype = signatureReturn(sig).btClass;
return MethodType.methodType(rtype, ptypes);
}
/*
* Code generation issues:
*
* Compiled LFs should be reusable in general.
* The biggest issue is how to decide when to pull a name into
* the bytecode, versus loading a reified form from the MH data.
*
* For example, an asType wrapper may require execution of a cast
* after a call to a MH. The target type of the cast can be placed
* as a constant in the LF itself. This will force the cast type
* to be compiled into the bytecodes and native code for the MH.
* Or, the target type of the cast can be erased in the LF, and
* loaded from the MH data. (Later on, if the MH as a whole is
* inlined, the data will flow into the inlined instance of the LF,
* as a constant, and the end result will be an optimal cast.)
*
* This erasure of cast types can be done with any use of
* reference types. It can also be done with whole method
* handles. Erasing a method handle might leave behind
* LF code that executes correctly for any MH of a given
* type, and load the required MH from the enclosing MH's data.
* Or, the erasure might even erase the expected MT.
*
* Also, for direct MHs, the MemberName of the target
* could be erased, and loaded from the containing direct MH.
* As a simple case, a LF for all int-valued non-static
* field getters would perform a cast on its input argument
* (to non-constant base type derived from the MemberName)
* and load an integer value from the input object
* (at a non-constant offset also derived from the MemberName).
* Such MN-erased LFs would be inlinable back to optimized
* code, whenever a constant enclosing DMH is available
* to supply a constant MN from its data.
*
* The main problem here is to keep LFs reasonably generic,
* while ensuring that hot spots will inline good instances.
* "Reasonably generic" means that we don't end up with
* repeated versions of bytecode or machine code that do
* not differ in their optimized form. Repeated versions
* of machine would have the undesirable overheads of
* (a) redundant compilation work and (b) extra I$ pressure.
* To control repeated versions, we need to be ready to
* erase details from LFs and move them into MH data,
* whevener those details are not relevant to significant
* optimization. "Significant" means optimization of
* code that is actually hot.
*
* Achieving this may require dynamic splitting of MHs, by replacing
* a generic LF with a more specialized one, on the same MH,
* if (a) the MH is frequently executed and (b) the MH cannot
* be inlined into a containing caller, such as an invokedynamic.
*
* Compiled LFs that are no longer used should be GC-able.
* If they contain non-BCP references, they should be properly
* interlinked with the class loader(s) that their embedded types
* depend on. This probably means that reusable compiled LFs
* will be tabulated (indexed) on relevant class loaders,
* or else that the tables that cache them will have weak links.
*/
/**
* Make this LF directly executable, as part of a MethodHandle.
* Invariant: Every MH which is invoked must prepare its LF
* before invocation.
* (In principle, the JVM could do this very lazily,
* as a sort of pre-invocation linkage step.)
*/
public void prepare() {
if (COMPILE_THRESHOLD == 0) {
compileToBytecode();
}
if (this.vmentry != null) {
// already prepared (e.g., a primitive DMH invoker form)
return;
}
LambdaForm prep = getPreparedForm(basicTypeSignature());
this.vmentry = prep.vmentry;
// TO DO: Maybe add invokeGeneric, invokeWithArguments
}
/** Generate optimizable bytecode for this form. */
MemberName compileToBytecode() {
MethodType invokerType = methodType();
assert(vmentry == null || vmentry.getMethodType().basicType().equals(invokerType));
if (vmentry != null && isCompiled) {
return vmentry; // already compiled somehow
}
try {
vmentry = InvokerBytecodeGenerator.generateCustomizedCode(this, invokerType);
if (TRACE_INTERPRETER)
traceInterpreter("compileToBytecode", this);
isCompiled = true;
return vmentry;
} catch (Error | Exception ex) {
throw newInternalError(this.toString(), ex);
}
}
private static void computeInitialPreparedForms() {
// Find all predefined invokers and associate them with canonical empty lambda forms.
for (MemberName m : MemberName.getFactory().getMethods(LambdaForm.class, false, null, null, null)) {
if (!m.isStatic() || !m.isPackage()) continue;
MethodType mt = m.getMethodType();
if (mt.parameterCount() > 0 &&
mt.parameterType(0) == MethodHandle.class &&
m.getName().startsWith("interpret_")) {
String sig = basicTypeSignature(mt);
assert(m.getName().equals("interpret" + sig.substring(sig.indexOf('_'))));
LambdaForm form = new LambdaForm(sig);
form.vmentry = m;
form = mt.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, form);
}
}
}
// Set this false to disable use of the interpret_L methods defined in this file.
private static final boolean USE_PREDEFINED_INTERPRET_METHODS = true;
// The following are predefined exact invokers. The system must build
// a separate invoker for each distinct signature.
static Object interpret_L(MethodHandle mh) throws Throwable {
Object[] av = {mh};
String sig = null;
assert(argumentTypesMatch(sig = "L_L", av));
Object res = mh.form.interpretWithArguments(av);
assert(returnTypesMatch(sig, av, res));
return res;
}
static Object interpret_L(MethodHandle mh, Object x1) throws Throwable {
Object[] av = {mh, x1};
String sig = null;
assert(argumentTypesMatch(sig = "LL_L", av));
Object res = mh.form.interpretWithArguments(av);
assert(returnTypesMatch(sig, av, res));
return res;
}
static Object interpret_L(MethodHandle mh, Object x1, Object x2) throws Throwable {
Object[] av = {mh, x1, x2};
String sig = null;
assert(argumentTypesMatch(sig = "LLL_L", av));
Object res = mh.form.interpretWithArguments(av);
assert(returnTypesMatch(sig, av, res));
return res;
}
private static LambdaForm getPreparedForm(String sig) {
MethodType mtype = signatureType(sig);
LambdaForm prep = mtype.form().cachedLambdaForm(MethodTypeForm.LF_INTERPRET);
if (prep != null) return prep;
assert(isValidSignature(sig));
prep = new LambdaForm(sig);
prep.vmentry = InvokerBytecodeGenerator.generateLambdaFormInterpreterEntryPoint(sig);
return mtype.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, prep);
}
// The next few routines are called only from assert expressions
// They verify that the built-in invokers process the correct raw data types.
private static boolean argumentTypesMatch(String sig, Object[] av) {
int arity = signatureArity(sig);
assert(av.length == arity) : "av.length == arity: av.length=" + av.length + ", arity=" + arity;
assert(av[0] instanceof MethodHandle) : "av[0] not instace of MethodHandle: " + av[0];
MethodHandle mh = (MethodHandle) av[0];
MethodType mt = mh.type();
assert(mt.parameterCount() == arity-1);
for (int i = 0; i < av.length; i++) {
Class<?> pt = (i == 0 ? MethodHandle.class : mt.parameterType(i-1));
assert(valueMatches(basicType(sig.charAt(i)), pt, av[i]));
}
return true;
}
private static boolean valueMatches(BasicType tc, Class<?> type, Object x) {
// The following line is needed because (...)void method handles can use non-void invokers
if (type == void.class) tc = V_TYPE; // can drop any kind of value
assert tc == basicType(type) : tc + " == basicType(" + type + ")=" + basicType(type);
switch (tc) {
case I_TYPE: assert checkInt(type, x) : "checkInt(" + type + "," + x +")"; break;
case J_TYPE: assert x instanceof Long : "instanceof Long: " + x; break;
case F_TYPE: assert x instanceof Float : "instanceof Float: " + x; break;
case D_TYPE: assert x instanceof Double : "instanceof Double: " + x; break;
case L_TYPE: assert checkRef(type, x) : "checkRef(" + type + "," + x + ")"; break;
case V_TYPE: break; // allow anything here; will be dropped
default: assert(false);
}
return true;
}
private static boolean returnTypesMatch(String sig, Object[] av, Object res) {
MethodHandle mh = (MethodHandle) av[0];
return valueMatches(signatureReturn(sig), mh.type().returnType(), res);
}
private static boolean checkInt(Class<?> type, Object x) {
assert(x instanceof Integer);
if (type == int.class) return true;
Wrapper w = Wrapper.forBasicType(type);
assert(w.isSubwordOrInt());
Object x1 = Wrapper.INT.wrap(w.wrap(x));
return x.equals(x1);
}
private static boolean checkRef(Class<?> type, Object x) {
assert(!type.isPrimitive());
if (x == null) return true;
if (type.isInterface()) return true;
return type.isInstance(x);
}
/** If the invocation count hits the threshold we spin bytecodes and call that subsequently. */
private static final int COMPILE_THRESHOLD;
static {
COMPILE_THRESHOLD = Math.max(-1, MethodHandleStatics.COMPILE_THRESHOLD);
}
private int invocationCounter = 0;
@Hidden
@DontInline
/** Interpretively invoke this form on the given arguments. */
Object interpretWithArguments(Object... argumentValues) throws Throwable {
if (TRACE_INTERPRETER)
return interpretWithArgumentsTracing(argumentValues);
checkInvocationCounter();
assert(arityCheck(argumentValues));
Object[] values = Arrays.copyOf(argumentValues, names.length);
for (int i = argumentValues.length; i < values.length; i++) {
values[i] = interpretName(names[i], values);
}
Object rv = (result < 0) ? null : values[result];
assert(resultCheck(argumentValues, rv));
return rv;
}
@Hidden
@DontInline
/** Evaluate a single Name within this form, applying its function to its arguments. */
Object interpretName(Name name, Object[] values) throws Throwable {
if (TRACE_INTERPRETER)
traceInterpreter("| interpretName", name.debugString(), (Object[]) null);
Object[] arguments = Arrays.copyOf(name.arguments, name.arguments.length, Object[].class);
for (int i = 0; i < arguments.length; i++) {
Object a = arguments[i];
if (a instanceof Name) {
int i2 = ((Name)a).index();
assert(names[i2] == a);
a = values[i2];
arguments[i] = a;
}
}
return name.function.invokeWithArguments(arguments);
}
private void checkInvocationCounter() {
if (COMPILE_THRESHOLD != 0 &&
invocationCounter < COMPILE_THRESHOLD) {
invocationCounter++; // benign race
if (invocationCounter >= COMPILE_THRESHOLD) {
// Replace vmentry with a bytecode version of this LF.
compileToBytecode();
}
}
}
Object interpretWithArgumentsTracing(Object... argumentValues) throws Throwable {
traceInterpreter("[ interpretWithArguments", this, argumentValues);
if (invocationCounter < COMPILE_THRESHOLD) {
int ctr = invocationCounter++; // benign race
traceInterpreter("| invocationCounter", ctr);
if (invocationCounter >= COMPILE_THRESHOLD) {
compileToBytecode();
}
}
Object rval;
try {
assert(arityCheck(argumentValues));
Object[] values = Arrays.copyOf(argumentValues, names.length);
for (int i = argumentValues.length; i < values.length; i++) {
values[i] = interpretName(names[i], values);
}
rval = (result < 0) ? null : values[result];
} catch (Throwable ex) {
traceInterpreter("] throw =>", ex);
throw ex;
}
traceInterpreter("] return =>", rval);
return rval;
}
static void traceInterpreter(String event, Object obj, Object... args) {
if (TRACE_INTERPRETER) {
System.out.println("LFI: "+event+" "+(obj != null ? obj : "")+(args != null && args.length != 0 ? Arrays.asList(args) : ""));
}
}
static void traceInterpreter(String event, Object obj) {
traceInterpreter(event, obj, (Object[])null);
}
private boolean arityCheck(Object[] argumentValues) {
assert(argumentValues.length == arity) : arity+"!="+Arrays.asList(argumentValues)+".length";
// also check that the leading (receiver) argument is somehow bound to this LF:
assert(argumentValues[0] instanceof MethodHandle) : "not MH: " + argumentValues[0];
MethodHandle mh = (MethodHandle) argumentValues[0];
assert(mh.internalForm() == this);
// note: argument #0 could also be an interface wrapper, in the future
argumentTypesMatch(basicTypeSignature(), argumentValues);
return true;
}
private boolean resultCheck(Object[] argumentValues, Object result) {
MethodHandle mh = (MethodHandle) argumentValues[0];
MethodType mt = mh.type();
assert(valueMatches(returnType(), mt.returnType(), result));
return true;
}
private boolean isEmpty() {
if (result < 0)
return (names.length == arity);
else if (result == arity && names.length == arity + 1)
return names[arity].isConstantZero();
else
return false;
}
public String toString() {
StringBuilder buf = new StringBuilder(debugName+"=Lambda(");
for (int i = 0; i < names.length; i++) {
if (i == arity) buf.append(")=>{");
Name n = names[i];
if (i >= arity) buf.append("\n ");
buf.append(n.paramString());
if (i < arity) {
if (i+1 < arity) buf.append(",");
continue;
}
buf.append("=").append(n.exprString());
buf.append(";");
}
if (arity == names.length) buf.append(")=>{");
buf.append(result < 0 ? "void" : names[result]).append("}");
if (TRACE_INTERPRETER) {
// Extra verbosity:
buf.append(":").append(basicTypeSignature());
buf.append("/").append(vmentry);
}
return buf.toString();
}
@Override
public boolean equals(Object obj) {
return obj instanceof LambdaForm && equals((LambdaForm)obj);
}
public boolean equals(LambdaForm that) {
if (this.result != that.result) return false;
return Arrays.equals(this.names, that.names);
}
public int hashCode() {
return result + 31 * Arrays.hashCode(names);
}
LambdaFormEditor editor() {
return LambdaFormEditor.lambdaFormEditor(this);
}
boolean contains(Name name) {
int pos = name.index();
if (pos >= 0) {
return pos < names.length && name.equals(names[pos]);
}
for (int i = arity; i < names.length; i++) {
if (name.equals(names[i]))
return true;
}
return false;
}
LambdaForm addArguments(int pos, BasicType... types) {
// names array has MH in slot 0; skip it.
int argpos = pos + 1;
assert(argpos <= arity);
int length = names.length;
int inTypes = types.length;
Name[] names2 = Arrays.copyOf(names, length + inTypes);
int arity2 = arity + inTypes;
int result2 = result;
if (result2 >= argpos)
result2 += inTypes;
// Note: The LF constructor will rename names2[argpos...].
// Make space for new arguments (shift temporaries).
System.arraycopy(names, argpos, names2, argpos + inTypes, length - argpos);
for (int i = 0; i < inTypes; i++) {
names2[argpos + i] = new Name(types[i]);
}
return new LambdaForm(debugName, arity2, names2, result2);
}
LambdaForm addArguments(int pos, List<Class<?>> types) {
return addArguments(pos, basicTypes(types));
}
LambdaForm permuteArguments(int skip, int[] reorder, BasicType[] types) {
// Note: When inArg = reorder[outArg], outArg is fed by a copy of inArg.
// The types are the types of the new (incoming) arguments.
int length = names.length;
int inTypes = types.length;
int outArgs = reorder.length;
assert(skip+outArgs == arity);
assert(permutedTypesMatch(reorder, types, names, skip));
int pos = 0;
// skip trivial first part of reordering:
while (pos < outArgs && reorder[pos] == pos) pos += 1;
Name[] names2 = new Name[length - outArgs + inTypes];
System.arraycopy(names, 0, names2, 0, skip+pos);
// copy the body:
int bodyLength = length - arity;
System.arraycopy(names, skip+outArgs, names2, skip+inTypes, bodyLength);
int arity2 = names2.length - bodyLength;
int result2 = result;
if (result2 >= 0) {
if (result2 < skip+outArgs) {
// return the corresponding inArg
result2 = reorder[result2-skip];
} else {
result2 = result2 - outArgs + inTypes;
}
}
// rework names in the body:
for (int j = pos; j < outArgs; j++) {
Name n = names[skip+j];
int i = reorder[j];
// replace names[skip+j] by names2[skip+i]
Name n2 = names2[skip+i];
if (n2 == null)
names2[skip+i] = n2 = new Name(types[i]);
else
assert(n2.type == types[i]);
for (int k = arity2; k < names2.length; k++) {
names2[k] = names2[k].replaceName(n, n2);
}
}
// some names are unused, but must be filled in
for (int i = skip+pos; i < arity2; i++) {
if (names2[i] == null)
names2[i] = argument(i, types[i - skip]);
}
for (int j = arity; j < names.length; j++) {
int i = j - arity + arity2;
// replace names2[i] by names[j]
Name n = names[j];
Name n2 = names2[i];
if (n != n2) {
for (int k = i+1; k < names2.length; k++) {
names2[k] = names2[k].replaceName(n, n2);
}
}
}
return new LambdaForm(debugName, arity2, names2, result2);
}
static boolean permutedTypesMatch(int[] reorder, BasicType[] types, Name[] names, int skip) {
int inTypes = types.length;
int outArgs = reorder.length;
for (int i = 0; i < outArgs; i++) {
assert(names[skip+i].isParam());
assert(names[skip+i].type == types[reorder[i]]);
}
return true;
}
static class NamedFunction {
final MemberName member;
@Stable MethodHandle resolvedHandle;
@Stable MethodHandle invoker;
NamedFunction(MethodHandle resolvedHandle) {
this(resolvedHandle.internalMemberName(), resolvedHandle);
}
NamedFunction(MemberName member, MethodHandle resolvedHandle) {
this.member = member;
this.resolvedHandle = resolvedHandle;
// The following assert is almost always correct, but will fail for corner cases, such as PrivateInvokeTest.
//assert(!isInvokeBasic());
}
NamedFunction(MethodType basicInvokerType) {
assert(basicInvokerType == basicInvokerType.basicType()) : basicInvokerType;
if (basicInvokerType.parameterSlotCount() < MethodType.MAX_MH_INVOKER_ARITY) {
this.resolvedHandle = basicInvokerType.invokers().basicInvoker();
this.member = resolvedHandle.internalMemberName();
} else {
// necessary to pass BigArityTest
this.member = Invokers.invokeBasicMethod(basicInvokerType);
}
assert(isInvokeBasic());
}
private boolean isInvokeBasic() {
return member != null &&
member.isMethodHandleInvoke() &&
"invokeBasic".equals(member.getName());
}
// The next 3 constructors are used to break circular dependencies on MH.invokeStatic, etc.
// Any LambdaForm containing such a member is not interpretable.
// This is OK, since all such LFs are prepared with special primitive vmentry points.
// And even without the resolvedHandle, the name can still be compiled and optimized.
NamedFunction(Method method) {
this(new MemberName(method));
}
NamedFunction(Field field) {
this(new MemberName(field));
}
NamedFunction(MemberName member) {
this.member = member;
this.resolvedHandle = null;
}
MethodHandle resolvedHandle() {
if (resolvedHandle == null) resolve();
return resolvedHandle;
}
void resolve() {
resolvedHandle = DirectMethodHandle.make(member);
}
@Override
public boolean equals(Object other) {
if (this == other) return true;
if (other == null) return false;
if (!(other instanceof NamedFunction)) return false;
NamedFunction that = (NamedFunction) other;
return this.member != null && this.member.equals(that.member);
}
@Override
public int hashCode() {
if (member != null)
return member.hashCode();
return super.hashCode();
}
// Put the predefined NamedFunction invokers into the table.
static void initializeInvokers() {
for (MemberName m : MemberName.getFactory().getMethods(NamedFunction.class, false, null, null, null)) {
if (!m.isStatic() || !m.isPackage()) continue;
MethodType type = m.getMethodType();
if (type.equals(INVOKER_METHOD_TYPE) &&
m.getName().startsWith("invoke_")) {
String sig = m.getName().substring("invoke_".length());
int arity = LambdaForm.signatureArity(sig);
MethodType srcType = MethodType.genericMethodType(arity);
if (LambdaForm.signatureReturn(sig) == V_TYPE)
srcType = srcType.changeReturnType(void.class);
MethodTypeForm typeForm = srcType.form();
typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, DirectMethodHandle.make(m));
}
}
}
// The following are predefined NamedFunction invokers. The system must build
// a separate invoker for each distinct signature.
/** void return type invokers. */
@Hidden
static Object invoke__V(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(0, void.class, mh, a));
mh.invokeBasic();
return null;
}
@Hidden
static Object invoke_L_V(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(1, void.class, mh, a));
mh.invokeBasic(a[0]);
return null;
}
@Hidden
static Object invoke_LL_V(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(2, void.class, mh, a));
mh.invokeBasic(a[0], a[1]);
return null;
}
@Hidden
static Object invoke_LLL_V(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(3, void.class, mh, a));
mh.invokeBasic(a[0], a[1], a[2]);
return null;
}
@Hidden
static Object invoke_LLLL_V(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(4, void.class, mh, a));
mh.invokeBasic(a[0], a[1], a[2], a[3]);
return null;
}
@Hidden
static Object invoke_LLLLL_V(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(5, void.class, mh, a));
mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
return null;
}
/** Object return type invokers. */
@Hidden
static Object invoke__L(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(0, mh, a));
return mh.invokeBasic();
}
@Hidden
static Object invoke_L_L(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(1, mh, a));
return mh.invokeBasic(a[0]);
}
@Hidden
static Object invoke_LL_L(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(2, mh, a));
return mh.invokeBasic(a[0], a[1]);
}
@Hidden
static Object invoke_LLL_L(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(3, mh, a));
return mh.invokeBasic(a[0], a[1], a[2]);
}
@Hidden
static Object invoke_LLLL_L(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(4, mh, a));
return mh.invokeBasic(a[0], a[1], a[2], a[3]);
}
@Hidden
static Object invoke_LLLLL_L(MethodHandle mh, Object[] a) throws Throwable {
assert(arityCheck(5, mh, a));
return mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
}
private static boolean arityCheck(int arity, MethodHandle mh, Object[] a) {
return arityCheck(arity, Object.class, mh, a);
}
private static boolean arityCheck(int arity, Class<?> rtype, MethodHandle mh, Object[] a) {
assert(a.length == arity)
: Arrays.asList(a.length, arity);
assert(mh.type().basicType() == MethodType.genericMethodType(arity).changeReturnType(rtype))
: Arrays.asList(mh, rtype, arity);
MemberName member = mh.internalMemberName();
if (member != null && member.getName().equals("invokeBasic") && member.isMethodHandleInvoke()) {
assert(arity > 0);
assert(a[0] instanceof MethodHandle);
MethodHandle mh2 = (MethodHandle) a[0];
assert(mh2.type().basicType() == MethodType.genericMethodType(arity-1).changeReturnType(rtype))
: Arrays.asList(member, mh2, rtype, arity);
}
return true;
}
static final MethodType INVOKER_METHOD_TYPE =
MethodType.methodType(Object.class, MethodHandle.class, Object[].class);
private static MethodHandle computeInvoker(MethodTypeForm typeForm) {
typeForm = typeForm.basicType().form(); // normalize to basic type
MethodHandle mh = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV);
if (mh != null) return mh;
MemberName invoker = InvokerBytecodeGenerator.generateNamedFunctionInvoker(typeForm); // this could take a while
mh = DirectMethodHandle.make(invoker);
MethodHandle mh2 = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV);
if (mh2 != null) return mh2; // benign race
if (!mh.type().equals(INVOKER_METHOD_TYPE))
throw newInternalError(mh.debugString());
return typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, mh);
}
@Hidden
Object invokeWithArguments(Object... arguments) throws Throwable {
// If we have a cached invoker, call it right away.
// NOTE: The invoker always returns a reference value.
if (TRACE_INTERPRETER) return invokeWithArgumentsTracing(arguments);
assert(checkArgumentTypes(arguments, methodType()));
return invoker().invokeBasic(resolvedHandle(), arguments);
}
@Hidden
Object invokeWithArgumentsTracing(Object[] arguments) throws Throwable {
Object rval;
try {
traceInterpreter("[ call", this, arguments);
if (invoker == null) {
traceInterpreter("| getInvoker", this);
invoker();
}
if (resolvedHandle == null) {
traceInterpreter("| resolve", this);
resolvedHandle();
}
assert(checkArgumentTypes(arguments, methodType()));
rval = invoker().invokeBasic(resolvedHandle(), arguments);
} catch (Throwable ex) {
traceInterpreter("] throw =>", ex);
throw ex;
}
traceInterpreter("] return =>", rval);
return rval;
}
private MethodHandle invoker() {
if (invoker != null) return invoker;
// Get an invoker and cache it.
return invoker = computeInvoker(methodType().form());
}
private static boolean checkArgumentTypes(Object[] arguments, MethodType methodType) {
if (true) return true; // FIXME
MethodType dstType = methodType.form().erasedType();
MethodType srcType = dstType.basicType().wrap();
Class<?>[] ptypes = new Class<?>[arguments.length];
for (int i = 0; i < arguments.length; i++) {
Object arg = arguments[i];
Class<?> ptype = arg == null ? Object.class : arg.getClass();
// If the dest. type is a primitive we keep the
// argument type.
ptypes[i] = dstType.parameterType(i).isPrimitive() ? ptype : Object.class;
}
MethodType argType = MethodType.methodType(srcType.returnType(), ptypes).wrap();
assert(argType.isConvertibleTo(srcType)) : "wrong argument types: cannot convert " + argType + " to " + srcType;
return true;
}
MethodType methodType() {
if (resolvedHandle != null)
return resolvedHandle.type();
else
// only for certain internal LFs during bootstrapping
return member.getInvocationType();
}
MemberName member() {
assert(assertMemberIsConsistent());
return member;
}
// Called only from assert.
private boolean assertMemberIsConsistent() {
if (resolvedHandle instanceof DirectMethodHandle) {
MemberName m = resolvedHandle.internalMemberName();
assert(m.equals(member));
}
return true;
}
Class<?> memberDeclaringClassOrNull() {
return (member == null) ? null : member.getDeclaringClass();
}
BasicType returnType() {
return basicType(methodType().returnType());
}
BasicType parameterType(int n) {
return basicType(methodType().parameterType(n));
}
int arity() {
return methodType().parameterCount();
}
public String toString() {
if (member == null) return String.valueOf(resolvedHandle);
return member.getDeclaringClass().getSimpleName()+"."+member.getName();
}
public boolean isIdentity() {
return this.equals(identity(returnType()));
}
public boolean isConstantZero() {
return this.equals(constantZero(returnType()));
}
public MethodHandleImpl.Intrinsic intrinsicName() {
return resolvedHandle == null ? MethodHandleImpl.Intrinsic.NONE
: resolvedHandle.intrinsicName();
}
}
public static String basicTypeSignature(MethodType type) {
char[] sig = new char[type.parameterCount() + 2];
int sigp = 0;
for (Class<?> pt : type.parameterList()) {
sig[sigp++] = basicTypeChar(pt);
}
sig[sigp++] = '_';
sig[sigp++] = basicTypeChar(type.returnType());
assert(sigp == sig.length);
return String.valueOf(sig);
}
public static String shortenSignature(String signature) {
// Hack to make signatures more readable when they show up in method names.
final int NO_CHAR = -1, MIN_RUN = 3;
int c0, c1 = NO_CHAR, c1reps = 0;
StringBuilder buf = null;
int len = signature.length();
if (len < MIN_RUN) return signature;
for (int i = 0; i <= len; i++) {
// shift in the next char:
c0 = c1; c1 = (i == len ? NO_CHAR : signature.charAt(i));
if (c1 == c0) { ++c1reps; continue; }
// shift in the next count:
int c0reps = c1reps; c1reps = 1;
// end of a character run
if (c0reps < MIN_RUN) {
if (buf != null) {
while (--c0reps >= 0)
buf.append((char)c0);
}
continue;
}
// found three or more in a row
if (buf == null)
buf = new StringBuilder().append(signature, 0, i - c0reps);
buf.append((char)c0).append(c0reps);
}
return (buf == null) ? signature : buf.toString();
}
static final class Name {
final BasicType type;
private short index;
final NamedFunction function;
final Object constraint; // additional type information, if not null
@Stable final Object[] arguments;
private Name(int index, BasicType type, NamedFunction function, Object[] arguments) {
this.index = (short)index;
this.type = type;
this.function = function;
this.arguments = arguments;
this.constraint = null;
assert(this.index == index);
}
private Name(Name that, Object constraint) {
this.index = that.index;
this.type = that.type;
this.function = that.function;
this.arguments = that.arguments;
this.constraint = constraint;
assert(constraint == null || isParam()); // only params have constraints
assert(constraint == null || constraint instanceof BoundMethodHandle.SpeciesData || constraint instanceof Class);
}
Name(MethodHandle function, Object... arguments) {
this(new NamedFunction(function), arguments);
}
Name(MethodType functionType, Object... arguments) {
this(new NamedFunction(functionType), arguments);
assert(arguments[0] instanceof Name && ((Name)arguments[0]).type == L_TYPE);
}
Name(MemberName function, Object... arguments) {
this(new NamedFunction(function), arguments);
}
Name(NamedFunction function, Object... arguments) {
this(-1, function.returnType(), function, arguments = Arrays.copyOf(arguments, arguments.length, Object[].class));
assert(arguments.length == function.arity()) : "arity mismatch: arguments.length=" + arguments.length + " == function.arity()=" + function.arity() + " in " + debugString();
for (int i = 0; i < arguments.length; i++)
assert(typesMatch(function.parameterType(i), arguments[i])) : "types don't match: function.parameterType(" + i + ")=" + function.parameterType(i) + ", arguments[" + i + "]=" + arguments[i] + " in " + debugString();
}
/** Create a raw parameter of the given type, with an expected index. */
Name(int index, BasicType type) {
this(index, type, null, null);
}
/** Create a raw parameter of the given type. */
Name(BasicType type) { this(-1, type); }
BasicType type() { return type; }
int index() { return index; }
boolean initIndex(int i) {
if (index != i) {
if (index != -1) return false;
index = (short)i;
}
return true;
}
char typeChar() {
return type.btChar;
}
void resolve() {
if (function != null)
function.resolve();
}
Name newIndex(int i) {
if (initIndex(i)) return this;
return cloneWithIndex(i);
}
Name cloneWithIndex(int i) {
Object[] newArguments = (arguments == null) ? null : arguments.clone();
return new Name(i, type, function, newArguments).withConstraint(constraint);
}
Name withConstraint(Object constraint) {
if (constraint == this.constraint) return this;
return new Name(this, constraint);
}
Name replaceName(Name oldName, Name newName) { // FIXME: use replaceNames uniformly
if (oldName == newName) return this;
@SuppressWarnings("LocalVariableHidesMemberVariable")
Object[] arguments = this.arguments;
if (arguments == null) return this;
boolean replaced = false;
for (int j = 0; j < arguments.length; j++) {
if (arguments[j] == oldName) {
if (!replaced) {
replaced = true;
arguments = arguments.clone();
}
arguments[j] = newName;
}
}
if (!replaced) return this;
return new Name(function, arguments);
}
/** In the arguments of this Name, replace oldNames[i] pairwise by newNames[i].
* Limit such replacements to {@code start<=i<end}. Return possibly changed self.
*/
Name replaceNames(Name[] oldNames, Name[] newNames, int start, int end) {
if (start >= end) return this;
@SuppressWarnings("LocalVariableHidesMemberVariable")
Object[] arguments = this.arguments;
boolean replaced = false;
eachArg:
for (int j = 0; j < arguments.length; j++) {
if (arguments[j] instanceof Name) {
Name n = (Name) arguments[j];
int check = n.index;
// harmless check to see if the thing is already in newNames:
if (check >= 0 && check < newNames.length && n == newNames[check])
continue eachArg;
// n might not have the correct index: n != oldNames[n.index].
for (int i = start; i < end; i++) {
if (n == oldNames[i]) {
if (n == newNames[i])
continue eachArg;
if (!replaced) {
replaced = true;
arguments = arguments.clone();
}
arguments[j] = newNames[i];
continue eachArg;
}
}
}
}
if (!replaced) return this;
return new Name(function, arguments);
}
void internArguments() {
@SuppressWarnings("LocalVariableHidesMemberVariable")
Object[] arguments = this.arguments;
for (int j = 0; j < arguments.length; j++) {
if (arguments[j] instanceof Name) {
Name n = (Name) arguments[j];
if (n.isParam() && n.index < INTERNED_ARGUMENT_LIMIT)
arguments[j] = internArgument(n);
}
}
}
boolean isParam() {
return function == null;
}
boolean isConstantZero() {
return !isParam() && arguments.length == 0 && function.isConstantZero();
}
public String toString() {
return (isParam()?"a":"t")+(index >= 0 ? index : System.identityHashCode(this))+":"+typeChar();
}
public String debugString() {
String s = paramString();
return (function == null) ? s : s + "=" + exprString();
}
public String paramString() {
String s = toString();
Object c = constraint;
if (c == null)
return s;
if (c instanceof Class) c = ((Class<?>)c).getSimpleName();
return s + "/" + c;
}
public String exprString() {
if (function == null) return toString();
StringBuilder buf = new StringBuilder(function.toString());
buf.append("(");
String cma = "";
for (Object a : arguments) {
buf.append(cma); cma = ",";
if (a instanceof Name || a instanceof Integer)
buf.append(a);
else
buf.append("(").append(a).append(")");
}
buf.append(")");
return buf.toString();
}
static boolean typesMatch(BasicType parameterType, Object object) {
if (object instanceof Name) {
return ((Name)object).type == parameterType;
}
switch (parameterType) {
case I_TYPE: return object instanceof Integer;
case J_TYPE: return object instanceof Long;
case F_TYPE: return object instanceof Float;
case D_TYPE: return object instanceof Double;
}
assert(parameterType == L_TYPE);
return true;
}
/** Return the index of the last occurrence of n in the argument array.
* Return -1 if the name is not used.
*/
int lastUseIndex(Name n) {
if (arguments == null) return -1;
for (int i = arguments.length; --i >= 0; ) {
if (arguments[i] == n) return i;
}
return -1;
}
/** Return the number of occurrences of n in the argument array.
* Return 0 if the name is not used.
*/
int useCount(Name n) {
if (arguments == null) return 0;
int count = 0;
for (int i = arguments.length; --i >= 0; ) {
if (arguments[i] == n) ++count;
}
return count;
}
boolean contains(Name n) {
return this == n || lastUseIndex(n) >= 0;
}
public boolean equals(Name that) {
if (this == that) return true;
if (isParam())
// each parameter is a unique atom
return false; // this != that
return
//this.index == that.index &&
this.type == that.type &&
this.function.equals(that.function) &&
Arrays.equals(this.arguments, that.arguments);
}
@Override
public boolean equals(Object x) {
return x instanceof Name && equals((Name)x);
}
@Override
public int hashCode() {
if (isParam())
return index | (type.ordinal() << 8);
return function.hashCode() ^ Arrays.hashCode(arguments);
}
}
/** Return the index of the last name which contains n as an argument.
* Return -1 if the name is not used. Return names.length if it is the return value.
*/
int lastUseIndex(Name n) {
int ni = n.index, nmax = names.length;
assert(names[ni] == n);
if (result == ni) return nmax; // live all the way beyond the end
for (int i = nmax; --i > ni; ) {
if (names[i].lastUseIndex(n) >= 0)
return i;
}
return -1;
}
/** Return the number of times n is used as an argument or return value. */
int useCount(Name n) {
int ni = n.index, nmax = names.length;
int end = lastUseIndex(n);
if (end < 0) return 0;
int count = 0;
if (end == nmax) { count++; end--; }
int beg = n.index() + 1;
if (beg < arity) beg = arity;
for (int i = beg; i <= end; i++) {
count += names[i].useCount(n);
}
return count;
}
static Name argument(int which, char type) {
return argument(which, basicType(type));
}
static Name argument(int which, BasicType type) {
if (which >= INTERNED_ARGUMENT_LIMIT)
return new Name(which, type);
return INTERNED_ARGUMENTS[type.ordinal()][which];
}
static Name internArgument(Name n) {
assert(n.isParam()) : "not param: " + n;
assert(n.index < INTERNED_ARGUMENT_LIMIT);
if (n.constraint != null) return n;
return argument(n.index, n.type);
}
static Name[] arguments(int extra, String types) {
int length = types.length();
Name[] names = new Name[length + extra];
for (int i = 0; i < length; i++)
names[i] = argument(i, types.charAt(i));
return names;
}
static Name[] arguments(int extra, char... types) {
int length = types.length;
Name[] names = new Name[length + extra];
for (int i = 0; i < length; i++)
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