1 /*
2 * Copyright (c) 2011, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang.invoke;
27
28 import jdk.internal.perf.PerfCounter;
29 import jdk.internal.vm.annotation.DontInline;
30 import jdk.internal.vm.annotation.Stable;
31 import sun.invoke.util.Wrapper;
32
33 import java.lang.annotation.ElementType;
34 import java.lang.annotation.Retention;
35 import java.lang.annotation.RetentionPolicy;
36 import java.lang.annotation.Target;
37 import java.lang.reflect.Method;
38 import java.util.Arrays;
39 import java.util.HashMap;
40
41 import static java.lang.invoke.LambdaForm.BasicType.*;
42 import static java.lang.invoke.MethodHandleNatives.Constants.REF_invokeStatic;
43 import static java.lang.invoke.MethodHandleStatics.*;
44 import java.util.Objects;
45
46 /**
47 * The symbolic, non-executable form of a method handle's invocation semantics.
48 * It consists of a series of names.
49 * The first N (N=arity) names are parameters,
50 * while any remaining names are temporary values.
51 * Each temporary specifies the application of a function to some arguments.
52 * The functions are method handles, while the arguments are mixes of
53 * constant values and local names.
54 * The result of the lambda is defined as one of the names, often the last one.
55 * <p>
56 * Here is an approximate grammar:
57 * <blockquote><pre>{@code
58 * LambdaForm = "(" ArgName* ")=>{" TempName* Result "}"
59 * ArgName = "a" N ":" T
60 * TempName = "t" N ":" T "=" Function "(" Argument* ");"
61 * Function = ConstantValue
62 * Argument = NameRef | ConstantValue
63 * Result = NameRef | "void"
64 * NameRef = "a" N | "t" N
65 * N = (any whole number)
66 * T = "L" | "I" | "J" | "F" | "D" | "V"
67 * }</pre></blockquote>
68 * Names are numbered consecutively from left to right starting at zero.
69 * (The letters are merely a taste of syntax sugar.)
70 * Thus, the first temporary (if any) is always numbered N (where N=arity).
71 * Every occurrence of a name reference in an argument list must refer to
72 * a name previously defined within the same lambda.
73 * A lambda has a void result if and only if its result index is -1.
74 * If a temporary has the type "V", it cannot be the subject of a NameRef,
75 * even though possesses a number.
76 * Note that all reference types are erased to "L", which stands for {@code Object}.
77 * All subword types (boolean, byte, short, char) are erased to "I" which is {@code int}.
78 * The other types stand for the usual primitive types.
79 * <p>
80 * Function invocation closely follows the static rules of the Java verifier.
81 * Arguments and return values must exactly match when their "Name" types are
82 * considered.
83 * Conversions are allowed only if they do not change the erased type.
84 * <ul>
85 * <li>L = Object: casts are used freely to convert into and out of reference types
86 * <li>I = int: subword types are forcibly narrowed when passed as arguments (see {@code explicitCastArguments})
87 * <li>J = long: no implicit conversions
88 * <li>F = float: no implicit conversions
89 * <li>D = double: no implicit conversions
90 * <li>V = void: a function result may be void if and only if its Name is of type "V"
91 * </ul>
92 * Although implicit conversions are not allowed, explicit ones can easily be
93 * encoded by using temporary expressions which call type-transformed identity functions.
94 * <p>
95 * Examples:
96 * <blockquote><pre>{@code
97 * (a0:J)=>{ a0 }
98 * == identity(long)
99 * (a0:I)=>{ t1:V = System.out#println(a0); void }
100 * == System.out#println(int)
101 * (a0:L)=>{ t1:V = System.out#println(a0); a0 }
102 * == identity, with printing side-effect
103 * (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0);
104 * t3:L = BoundMethodHandle#target(a0);
105 * t4:L = MethodHandle#invoke(t3, t2, a1); t4 }
106 * == general invoker for unary insertArgument combination
107 * (a0:L, a1:L)=>{ t2:L = FilterMethodHandle#filter(a0);
108 * t3:L = MethodHandle#invoke(t2, a1);
109 * t4:L = FilterMethodHandle#target(a0);
110 * t5:L = MethodHandle#invoke(t4, t3); t5 }
111 * == general invoker for unary filterArgument combination
112 * (a0:L, a1:L)=>{ ...(same as previous example)...
113 * t5:L = MethodHandle#invoke(t4, t3, a1); t5 }
114 * == general invoker for unary/unary foldArgument combination
115 * (a0:L, a1:I)=>{ t2:I = identity(long).asType((int)->long)(a1); t2 }
116 * == invoker for identity method handle which performs i2l
117 * (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0);
118 * t3:L = Class#cast(t2,a1); t3 }
119 * == invoker for identity method handle which performs cast
120 * }</pre></blockquote>
121 * <p>
122 * @author John Rose, JSR 292 EG
123 */
124 class LambdaForm {
125 final int arity;
126 final int result;
127 final boolean forceInline;
128 final MethodHandle customized;
129 @Stable final Name[] names;
130 final String debugName;
131 final Kind kind;
132 MemberName vmentry; // low-level behavior, or null if not yet prepared
133 private boolean isCompiled;
134
135 // Either a LambdaForm cache (managed by LambdaFormEditor) or a link to uncustomized version (for customized LF)
136 volatile Object transformCache;
137
138 public static final int VOID_RESULT = -1, LAST_RESULT = -2;
139
140 enum BasicType {
141 L_TYPE('L', Object.class, Wrapper.OBJECT), // all reference types
142 I_TYPE('I', int.class, Wrapper.INT),
143 J_TYPE('J', long.class, Wrapper.LONG),
144 F_TYPE('F', float.class, Wrapper.FLOAT),
145 D_TYPE('D', double.class, Wrapper.DOUBLE), // all primitive types
146 V_TYPE('V', void.class, Wrapper.VOID); // not valid in all contexts
147
148 static final BasicType[] ALL_TYPES = BasicType.values();
149 static final BasicType[] ARG_TYPES = Arrays.copyOf(ALL_TYPES, ALL_TYPES.length-1);
150
151 static final int ARG_TYPE_LIMIT = ARG_TYPES.length;
152 static final int TYPE_LIMIT = ALL_TYPES.length;
153
154 final char btChar;
155 final Class<?> btClass;
156 final Wrapper btWrapper;
157
158 private BasicType(char btChar, Class<?> btClass, Wrapper wrapper) {
159 this.btChar = btChar;
160 this.btClass = btClass;
161 this.btWrapper = wrapper;
162 }
163
164 char basicTypeChar() {
165 return btChar;
166 }
167 Class<?> basicTypeClass() {
168 return btClass;
169 }
170 Wrapper basicTypeWrapper() {
171 return btWrapper;
172 }
173 int basicTypeSlots() {
174 return btWrapper.stackSlots();
175 }
176
177 static BasicType basicType(byte type) {
178 return ALL_TYPES[type];
179 }
180 static BasicType basicType(char type) {
181 switch (type) {
182 case 'L': return L_TYPE;
183 case 'I': return I_TYPE;
184 case 'J': return J_TYPE;
185 case 'F': return F_TYPE;
186 case 'D': return D_TYPE;
187 case 'V': return V_TYPE;
188 // all subword types are represented as ints
189 case 'Z':
190 case 'B':
191 case 'S':
192 case 'C':
193 return I_TYPE;
194 default:
195 throw newInternalError("Unknown type char: '"+type+"'");
196 }
197 }
198 static BasicType basicType(Wrapper type) {
199 char c = type.basicTypeChar();
200 return basicType(c);
201 }
202 static BasicType basicType(Class<?> type) {
203 if (!type.isPrimitive()) return L_TYPE;
204 return basicType(Wrapper.forPrimitiveType(type));
205 }
206 static BasicType[] basicTypes(String types) {
207 BasicType[] btypes = new BasicType[types.length()];
208 for (int i = 0; i < btypes.length; i++) {
209 btypes[i] = basicType(types.charAt(i));
210 }
211 return btypes;
212 }
213 static String basicTypeDesc(BasicType[] types) {
214 if (types == null) {
215 return null;
216 }
217 if (types.length == 0) {
218 return "";
219 }
220 StringBuilder sb = new StringBuilder();
221 for (BasicType bt : types) {
222 sb.append(bt.basicTypeChar());
223 }
224 return sb.toString();
225 }
226 static int[] basicTypeOrds(BasicType[] types) {
227 if (types == null) {
228 return null;
229 }
230 int[] a = new int[types.length];
231 for(int i = 0; i < types.length; ++i) {
232 a[i] = types[i].ordinal();
233 }
234 return a;
235 }
236
237 static char basicTypeChar(Class<?> type) {
238 return basicType(type).btChar;
239 }
240
241 static byte[] basicTypesOrd(Class<?>[] types) {
242 byte[] ords = new byte[types.length];
243 for (int i = 0; i < ords.length; i++) {
244 ords[i] = (byte)basicType(types[i]).ordinal();
245 }
246 return ords;
247 }
248
249 static boolean isBasicTypeChar(char c) {
250 return "LIJFDV".indexOf(c) >= 0;
251 }
252 static boolean isArgBasicTypeChar(char c) {
253 return "LIJFD".indexOf(c) >= 0;
254 }
255
256 static { assert(checkBasicType()); }
257 private static boolean checkBasicType() {
258 for (int i = 0; i < ARG_TYPE_LIMIT; i++) {
259 assert ARG_TYPES[i].ordinal() == i;
260 assert ARG_TYPES[i] == ALL_TYPES[i];
261 }
262 for (int i = 0; i < TYPE_LIMIT; i++) {
263 assert ALL_TYPES[i].ordinal() == i;
264 }
265 assert ALL_TYPES[TYPE_LIMIT - 1] == V_TYPE;
266 assert !Arrays.asList(ARG_TYPES).contains(V_TYPE);
267 return true;
268 }
269 }
270
271 enum Kind {
272 GENERIC(""),
273 ZERO("zero"),
274 IDENTITY("identity"),
275 BOUND_REINVOKER("BMH.reinvoke"),
276 REINVOKER("MH.reinvoke"),
277 DELEGATE("MH.delegate"),
278 DIRECT_INVOKE_VIRTUAL("DMH.invokeVirtual"),
279 DIRECT_INVOKE_SPECIAL("DMH.invokeSpecial"),
280 DIRECT_INVOKE_STATIC("DMH.invokeStatic"),
281 DIRECT_NEW_INVOKE_SPECIAL("DMH.newInvokeSpecial"),
282 DIRECT_INVOKE_INTERFACE("DMH.invokeInterface"),
283 DIRECT_INVOKE_STATIC_INIT("DMH.invokeStaticInit");
284
285 final String defaultLambdaName;
286 final String methodName;
287
288 private Kind(String defaultLambdaName) {
289 this.defaultLambdaName = defaultLambdaName;
290 int p = defaultLambdaName.indexOf('.');
291 if (p > -1) {
292 this.methodName = defaultLambdaName.substring(p + 1);
293 } else {
294 this.methodName = defaultLambdaName;
295 }
296 }
297 }
298
299 LambdaForm(String debugName,
300 int arity, Name[] names, int result) {
301 this(debugName, arity, names, result, /*forceInline=*/true, /*customized=*/null, Kind.GENERIC);
302 }
303 LambdaForm(String debugName,
304 int arity, Name[] names, int result, Kind kind) {
305 this(debugName, arity, names, result, /*forceInline=*/true, /*customized=*/null, kind);
306 }
307 LambdaForm(String debugName,
308 int arity, Name[] names, int result, boolean forceInline, MethodHandle customized) {
309 this(debugName, arity, names, result, forceInline, customized, Kind.GENERIC);
310 }
311 LambdaForm(String debugName,
312 int arity, Name[] names, int result, boolean forceInline, MethodHandle customized, Kind kind) {
313 assert(namesOK(arity, names));
314 this.arity = arity;
315 this.result = fixResult(result, names);
316 this.names = names.clone();
317 this.debugName = fixDebugName(debugName);
318 this.forceInline = forceInline;
319 this.customized = customized;
320 this.kind = kind;
321 int maxOutArity = normalize();
322 if (maxOutArity > MethodType.MAX_MH_INVOKER_ARITY) {
323 // Cannot use LF interpreter on very high arity expressions.
324 assert(maxOutArity <= MethodType.MAX_JVM_ARITY);
325 compileToBytecode();
326 }
327 }
328 LambdaForm(String debugName,
329 int arity, Name[] names) {
330 this(debugName, arity, names, LAST_RESULT, /*forceInline=*/true, /*customized=*/null, Kind.GENERIC);
331 }
332 LambdaForm(String debugName,
333 int arity, Name[] names, boolean forceInline) {
334 this(debugName, arity, names, LAST_RESULT, forceInline, /*customized=*/null, Kind.GENERIC);
335 }
336 LambdaForm(String debugName,
337 int arity, Name[] names, boolean forceInline, Kind kind) {
338 this(debugName, arity, names, LAST_RESULT, forceInline, /*customized=*/null, kind);
339 }
340 LambdaForm(String debugName,
341 Name[] formals, Name[] temps, Name result) {
342 this(debugName,
343 formals.length, buildNames(formals, temps, result), LAST_RESULT, /*forceInline=*/true, /*customized=*/null);
344 }
345 LambdaForm(String debugName,
346 Name[] formals, Name[] temps, Name result, boolean forceInline) {
347 this(debugName,
348 formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline, /*customized=*/null);
349 }
350
351 private static Name[] buildNames(Name[] formals, Name[] temps, Name result) {
352 int arity = formals.length;
353 int length = arity + temps.length + (result == null ? 0 : 1);
354 Name[] names = Arrays.copyOf(formals, length);
355 System.arraycopy(temps, 0, names, arity, temps.length);
356 if (result != null)
357 names[length - 1] = result;
358 return names;
359 }
360
361 private LambdaForm(MethodType mt) {
362 // Make a blank lambda form, which returns a constant zero or null.
363 // It is used as a template for managing the invocation of similar forms that are non-empty.
364 // Called only from getPreparedForm.
365 this.arity = mt.parameterCount();
366 this.result = (mt.returnType() == void.class || mt.returnType() == Void.class) ? -1 : arity;
367 this.names = buildEmptyNames(arity, mt, result == -1);
368 this.debugName = "LF.zero";
369 this.forceInline = true;
370 this.customized = null;
371 this.kind = Kind.GENERIC;
372 assert(nameRefsAreLegal());
373 assert(isEmpty());
374 String sig = null;
375 assert(isValidSignature(sig = basicTypeSignature()));
376 assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature();
377 }
378
379 private static Name[] buildEmptyNames(int arity, MethodType mt, boolean isVoid) {
380 Name[] names = arguments(isVoid ? 0 : 1, mt);
381 if (!isVoid) {
382 Name zero = new Name(constantZero(basicType(mt.returnType())));
383 names[arity] = zero.newIndex(arity);
384 }
385 return names;
386 }
387
388 private static int fixResult(int result, Name[] names) {
389 if (result == LAST_RESULT)
390 result = names.length - 1; // might still be void
391 if (result >= 0 && names[result].type == V_TYPE)
392 result = VOID_RESULT;
393 return result;
394 }
395
396 private static String fixDebugName(String debugName) {
397 if (DEBUG_NAME_COUNTERS != null) {
398 int under = debugName.indexOf('_');
399 int length = debugName.length();
400 if (under < 0) under = length;
401 String debugNameStem = debugName.substring(0, under);
402 Integer ctr;
403 synchronized (DEBUG_NAME_COUNTERS) {
404 ctr = DEBUG_NAME_COUNTERS.get(debugNameStem);
405 if (ctr == null) ctr = 0;
406 DEBUG_NAME_COUNTERS.put(debugNameStem, ctr+1);
407 }
408 StringBuilder buf = new StringBuilder(debugNameStem);
409 buf.append('_');
410 int leadingZero = buf.length();
411 buf.append((int) ctr);
412 for (int i = buf.length() - leadingZero; i < 3; i++)
413 buf.insert(leadingZero, '0');
414 if (under < length) {
415 ++under; // skip "_"
416 while (under < length && Character.isDigit(debugName.charAt(under))) {
417 ++under;
418 }
419 if (under < length && debugName.charAt(under) == '_') ++under;
420 if (under < length)
421 buf.append('_').append(debugName, under, length);
422 }
423 return buf.toString();
424 }
425 return debugName;
426 }
427
428 private static boolean namesOK(int arity, Name[] names) {
429 for (int i = 0; i < names.length; i++) {
430 Name n = names[i];
431 assert(n != null) : "n is null";
432 if (i < arity)
433 assert( n.isParam()) : n + " is not param at " + i;
434 else
435 assert(!n.isParam()) : n + " is param at " + i;
436 }
437 return true;
438 }
439
440 /** Customize LambdaForm for a particular MethodHandle */
441 LambdaForm customize(MethodHandle mh) {
442 LambdaForm customForm = new LambdaForm(debugName, arity, names, result, forceInline, mh, kind);
443 if (COMPILE_THRESHOLD >= 0 && isCompiled) {
444 // If shared LambdaForm has been compiled, compile customized version as well.
445 customForm.compileToBytecode();
446 }
447 customForm.transformCache = this; // LambdaFormEditor should always use uncustomized form.
448 return customForm;
449 }
450
451 /** Get uncustomized flavor of the LambdaForm */
452 LambdaForm uncustomize() {
453 if (customized == null) {
454 return this;
455 }
456 assert(transformCache != null); // Customized LambdaForm should always has a link to uncustomized version.
457 LambdaForm uncustomizedForm = (LambdaForm)transformCache;
458 if (COMPILE_THRESHOLD >= 0 && isCompiled) {
459 // If customized LambdaForm has been compiled, compile uncustomized version as well.
460 uncustomizedForm.compileToBytecode();
461 }
462 return uncustomizedForm;
463 }
464
465 /** Renumber and/or replace params so that they are interned and canonically numbered.
466 * @return maximum argument list length among the names (since we have to pass over them anyway)
467 */
468 private int normalize() {
469 Name[] oldNames = null;
470 int maxOutArity = 0;
471 int changesStart = 0;
472 for (int i = 0; i < names.length; i++) {
473 Name n = names[i];
474 if (!n.initIndex(i)) {
475 if (oldNames == null) {
476 oldNames = names.clone();
477 changesStart = i;
478 }
479 names[i] = n.cloneWithIndex(i);
480 }
481 if (n.arguments != null && maxOutArity < n.arguments.length)
482 maxOutArity = n.arguments.length;
483 }
484 if (oldNames != null) {
485 int startFixing = arity;
486 if (startFixing <= changesStart)
487 startFixing = changesStart+1;
488 for (int i = startFixing; i < names.length; i++) {
489 Name fixed = names[i].replaceNames(oldNames, names, changesStart, i);
490 names[i] = fixed.newIndex(i);
491 }
492 }
493 assert(nameRefsAreLegal());
494 int maxInterned = Math.min(arity, INTERNED_ARGUMENT_LIMIT);
495 boolean needIntern = false;
496 for (int i = 0; i < maxInterned; i++) {
497 Name n = names[i], n2 = internArgument(n);
498 if (n != n2) {
499 names[i] = n2;
500 needIntern = true;
501 }
502 }
503 if (needIntern) {
504 for (int i = arity; i < names.length; i++) {
505 names[i].internArguments();
506 }
507 }
508 assert(nameRefsAreLegal());
509 return maxOutArity;
510 }
511
512 /**
513 * Check that all embedded Name references are localizable to this lambda,
514 * and are properly ordered after their corresponding definitions.
515 * <p>
516 * Note that a Name can be local to multiple lambdas, as long as
517 * it possesses the same index in each use site.
518 * This allows Name references to be freely reused to construct
519 * fresh lambdas, without confusion.
520 */
521 boolean nameRefsAreLegal() {
522 assert(arity >= 0 && arity <= names.length);
523 assert(result >= -1 && result < names.length);
524 // Do all names possess an index consistent with their local definition order?
525 for (int i = 0; i < arity; i++) {
526 Name n = names[i];
527 assert(n.index() == i) : Arrays.asList(n.index(), i);
528 assert(n.isParam());
529 }
530 // Also, do all local name references
531 for (int i = arity; i < names.length; i++) {
532 Name n = names[i];
533 assert(n.index() == i);
534 for (Object arg : n.arguments) {
535 if (arg instanceof Name) {
536 Name n2 = (Name) arg;
537 int i2 = n2.index;
538 assert(0 <= i2 && i2 < names.length) : n.debugString() + ": 0 <= i2 && i2 < names.length: 0 <= " + i2 + " < " + names.length;
539 assert(names[i2] == n2) : Arrays.asList("-1-", i, "-2-", n.debugString(), "-3-", i2, "-4-", n2.debugString(), "-5-", names[i2].debugString(), "-6-", this);
540 assert(i2 < i); // ref must come after def!
541 }
542 }
543 }
544 return true;
545 }
546
547 /** Invoke this form on the given arguments. */
548 // final Object invoke(Object... args) throws Throwable {
549 // // NYI: fit this into the fast path?
550 // return interpretWithArguments(args);
551 // }
552
553 /** Report the return type. */
554 BasicType returnType() {
555 if (result < 0) return V_TYPE;
556 Name n = names[result];
557 return n.type;
558 }
559
560 /** Report the N-th argument type. */
561 BasicType parameterType(int n) {
562 return parameter(n).type;
563 }
564
565 /** Report the N-th argument name. */
566 Name parameter(int n) {
567 assert(n < arity);
568 Name param = names[n];
569 assert(param.isParam());
570 return param;
571 }
572
573 /** Report the N-th argument type constraint. */
574 Object parameterConstraint(int n) {
575 return parameter(n).constraint;
576 }
577
578 /** Report the arity. */
579 int arity() {
580 return arity;
581 }
582
583 /** Report the number of expressions (non-parameter names). */
584 int expressionCount() {
585 return names.length - arity;
586 }
587
588 /** Return the method type corresponding to my basic type signature. */
589 MethodType methodType() {
590 Class<?>[] ptypes = new Class<?>[arity];
591 for (int i = 0; i < arity; ++i) {
592 ptypes[i] = parameterType(i).btClass;
593 }
594 return MethodType.methodType(returnType().btClass, ptypes);
595 }
596
597 /** Return ABC_Z, where the ABC are parameter type characters, and Z is the return type character. */
598 final String basicTypeSignature() {
599 StringBuilder buf = new StringBuilder(arity() + 3);
600 for (int i = 0, a = arity(); i < a; i++)
601 buf.append(parameterType(i).basicTypeChar());
602 return buf.append('_').append(returnType().basicTypeChar()).toString();
603 }
604 static int signatureArity(String sig) {
605 assert(isValidSignature(sig));
606 return sig.indexOf('_');
607 }
608 static BasicType signatureReturn(String sig) {
609 return basicType(sig.charAt(signatureArity(sig) + 1));
610 }
611 static boolean isValidSignature(String sig) {
612 int arity = sig.indexOf('_');
613 if (arity < 0) return false; // must be of the form *_*
614 int siglen = sig.length();
615 if (siglen != arity + 2) return false; // *_X
616 for (int i = 0; i < siglen; i++) {
617 if (i == arity) continue; // skip '_'
618 char c = sig.charAt(i);
619 if (c == 'V')
620 return (i == siglen - 1 && arity == siglen - 2);
621 if (!isArgBasicTypeChar(c)) return false; // must be [LIJFD]
622 }
623 return true; // [LIJFD]*_[LIJFDV]
624 }
625 static MethodType signatureType(String sig) {
626 Class<?>[] ptypes = new Class<?>[signatureArity(sig)];
627 for (int i = 0; i < ptypes.length; i++)
628 ptypes[i] = basicType(sig.charAt(i)).btClass;
629 Class<?> rtype = signatureReturn(sig).btClass;
630 return MethodType.methodType(rtype, ptypes);
631 }
632
633 /**
634 * Check if i-th name is a call to MethodHandleImpl.selectAlternative.
635 */
636 boolean isSelectAlternative(int pos) {
637 // selectAlternative idiom:
638 // t_{n}:L=MethodHandleImpl.selectAlternative(...)
639 // t_{n+1}:?=MethodHandle.invokeBasic(t_{n}, ...)
640 if (pos+1 >= names.length) return false;
641 Name name0 = names[pos];
642 Name name1 = names[pos+1];
643 return name0.refersTo(MethodHandleImpl.class, "selectAlternative") &&
644 name1.isInvokeBasic() &&
645 name1.lastUseIndex(name0) == 0 && // t_{n+1}:?=MethodHandle.invokeBasic(t_{n}, ...)
646 lastUseIndex(name0) == pos+1; // t_{n} is local: used only in t_{n+1}
647 }
648
649 private boolean isMatchingIdiom(int pos, String idiomName, int nArgs) {
650 if (pos+2 >= names.length) return false;
651 Name name0 = names[pos];
652 Name name1 = names[pos+1];
653 Name name2 = names[pos+2];
654 return name1.refersTo(MethodHandleImpl.class, idiomName) &&
655 name0.isInvokeBasic() &&
656 name2.isInvokeBasic() &&
657 name1.lastUseIndex(name0) == nArgs && // t_{n+1}:L=MethodHandleImpl.<invoker>(<args>, t_{n});
658 lastUseIndex(name0) == pos+1 && // t_{n} is local: used only in t_{n+1}
659 name2.lastUseIndex(name1) == 1 && // t_{n+2}:?=MethodHandle.invokeBasic(*, t_{n+1})
660 lastUseIndex(name1) == pos+2; // t_{n+1} is local: used only in t_{n+2}
661 }
662
663 /**
664 * Check if i-th name is a start of GuardWithCatch idiom.
665 */
666 boolean isGuardWithCatch(int pos) {
667 // GuardWithCatch idiom:
668 // t_{n}:L=MethodHandle.invokeBasic(...)
669 // t_{n+1}:L=MethodHandleImpl.guardWithCatch(*, *, *, t_{n});
670 // t_{n+2}:?=MethodHandle.invokeBasic(*, t_{n+1})
671 return isMatchingIdiom(pos, "guardWithCatch", 3);
672 }
673
674 /**
675 * Check if i-th name is a start of the tryFinally idiom.
676 */
677 boolean isTryFinally(int pos) {
678 // tryFinally idiom:
679 // t_{n}:L=MethodHandle.invokeBasic(...)
680 // t_{n+1}:L=MethodHandleImpl.tryFinally(*, *, t_{n})
681 // t_{n+2}:?=MethodHandle.invokeBasic(*, t_{n+1})
682 return isMatchingIdiom(pos, "tryFinally", 2);
683 }
684
685 /**
686 * Check if i-th name is a start of the loop idiom.
687 */
688 boolean isLoop(int pos) {
689 // loop idiom:
690 // t_{n}:L=MethodHandle.invokeBasic(...)
691 // t_{n+1}:L=MethodHandleImpl.loop(types, *, *, *, *, t_{n})
692 // t_{n+2}:?=MethodHandle.invokeBasic(*, t_{n+1})
693 return isMatchingIdiom(pos, "loop", 5);
694 }
695
696 /*
697 * Code generation issues:
698 *
699 * Compiled LFs should be reusable in general.
700 * The biggest issue is how to decide when to pull a name into
701 * the bytecode, versus loading a reified form from the MH data.
702 *
703 * For example, an asType wrapper may require execution of a cast
704 * after a call to a MH. The target type of the cast can be placed
705 * as a constant in the LF itself. This will force the cast type
706 * to be compiled into the bytecodes and native code for the MH.
707 * Or, the target type of the cast can be erased in the LF, and
708 * loaded from the MH data. (Later on, if the MH as a whole is
709 * inlined, the data will flow into the inlined instance of the LF,
710 * as a constant, and the end result will be an optimal cast.)
711 *
712 * This erasure of cast types can be done with any use of
713 * reference types. It can also be done with whole method
714 * handles. Erasing a method handle might leave behind
715 * LF code that executes correctly for any MH of a given
716 * type, and load the required MH from the enclosing MH's data.
717 * Or, the erasure might even erase the expected MT.
718 *
719 * Also, for direct MHs, the MemberName of the target
720 * could be erased, and loaded from the containing direct MH.
721 * As a simple case, a LF for all int-valued non-static
722 * field getters would perform a cast on its input argument
723 * (to non-constant base type derived from the MemberName)
724 * and load an integer value from the input object
725 * (at a non-constant offset also derived from the MemberName).
726 * Such MN-erased LFs would be inlinable back to optimized
727 * code, whenever a constant enclosing DMH is available
728 * to supply a constant MN from its data.
729 *
730 * The main problem here is to keep LFs reasonably generic,
731 * while ensuring that hot spots will inline good instances.
732 * "Reasonably generic" means that we don't end up with
733 * repeated versions of bytecode or machine code that do
734 * not differ in their optimized form. Repeated versions
735 * of machine would have the undesirable overheads of
736 * (a) redundant compilation work and (b) extra I$ pressure.
737 * To control repeated versions, we need to be ready to
738 * erase details from LFs and move them into MH data,
739 * whevener those details are not relevant to significant
740 * optimization. "Significant" means optimization of
741 * code that is actually hot.
742 *
743 * Achieving this may require dynamic splitting of MHs, by replacing
744 * a generic LF with a more specialized one, on the same MH,
745 * if (a) the MH is frequently executed and (b) the MH cannot
746 * be inlined into a containing caller, such as an invokedynamic.
747 *
748 * Compiled LFs that are no longer used should be GC-able.
749 * If they contain non-BCP references, they should be properly
750 * interlinked with the class loader(s) that their embedded types
751 * depend on. This probably means that reusable compiled LFs
752 * will be tabulated (indexed) on relevant class loaders,
753 * or else that the tables that cache them will have weak links.
754 */
755
756 /**
757 * Make this LF directly executable, as part of a MethodHandle.
758 * Invariant: Every MH which is invoked must prepare its LF
759 * before invocation.
760 * (In principle, the JVM could do this very lazily,
761 * as a sort of pre-invocation linkage step.)
762 */
763 public void prepare() {
764 if (COMPILE_THRESHOLD == 0 && !forceInterpretation() && !isCompiled) {
765 compileToBytecode();
766 }
767 if (this.vmentry != null) {
768 // already prepared (e.g., a primitive DMH invoker form)
769 return;
770 }
771 MethodType mtype = methodType();
772 LambdaForm prep = mtype.form().cachedLambdaForm(MethodTypeForm.LF_INTERPRET);
773 if (prep == null) {
774 assert (isValidSignature(basicTypeSignature()));
775 prep = new LambdaForm(mtype);
776 prep.vmentry = InvokerBytecodeGenerator.generateLambdaFormInterpreterEntryPoint(mtype);
777 prep = mtype.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, prep);
778 }
779 this.vmentry = prep.vmentry;
780 // TO DO: Maybe add invokeGeneric, invokeWithArguments
781 }
782
783 private static @Stable PerfCounter LF_FAILED;
784
785 private static PerfCounter failedCompilationCounter() {
786 if (LF_FAILED == null) {
787 LF_FAILED = PerfCounter.newPerfCounter("java.lang.invoke.failedLambdaFormCompilations");
788 }
789 return LF_FAILED;
790 }
791
792 /** Generate optimizable bytecode for this form. */
793 void compileToBytecode() {
794 if (forceInterpretation()) {
795 return; // this should not be compiled
796 }
797 if (vmentry != null && isCompiled) {
798 return; // already compiled somehow
799 }
800 MethodType invokerType = methodType();
801 assert(vmentry == null || vmentry.getMethodType().basicType().equals(invokerType));
802 try {
803 vmentry = InvokerBytecodeGenerator.generateCustomizedCode(this, invokerType);
804 if (TRACE_INTERPRETER)
805 traceInterpreter("compileToBytecode", this);
806 isCompiled = true;
807 } catch (InvokerBytecodeGenerator.BytecodeGenerationException bge) {
808 // bytecode generation failed - mark this LambdaForm as to be run in interpretation mode only
809 invocationCounter = -1;
810 failedCompilationCounter().increment();
811 if (LOG_LF_COMPILATION_FAILURE) {
812 System.out.println("LambdaForm compilation failed: " + this);
813 bge.printStackTrace(System.out);
814 }
815 } catch (Error | Exception e) {
816 throw newInternalError(this.toString(), e);
817 }
818 }
819
820 private static void computeInitialPreparedForms() {
821 // Find all predefined invokers and associate them with canonical empty lambda forms.
822 for (MemberName m : MemberName.getFactory().getMethods(LambdaForm.class, false, null, null, null)) {
823 if (!m.isStatic() || !m.isPackage()) continue;
824 MethodType mt = m.getMethodType();
825 if (mt.parameterCount() > 0 &&
826 mt.parameterType(0) == MethodHandle.class &&
827 m.getName().startsWith("interpret_")) {
828 String sig = null;
829 assert((sig = basicTypeSignature(mt)) != null &&
830 m.getName().equals("interpret" + sig.substring(sig.indexOf('_'))));
831 LambdaForm form = new LambdaForm(mt);
832 form.vmentry = m;
833 form = mt.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, form);
834 }
835 }
836 }
837
838 // Set this false to disable use of the interpret_L methods defined in this file.
839 private static final boolean USE_PREDEFINED_INTERPRET_METHODS = true;
840
841 // The following are predefined exact invokers. The system must build
842 // a separate invoker for each distinct signature.
843 static Object interpret_L(MethodHandle mh) throws Throwable {
844 Object[] av = {mh};
845 String sig = null;
846 assert(argumentTypesMatch(sig = "L_L", av));
847 Object res = mh.form.interpretWithArguments(av);
848 assert(returnTypesMatch(sig, av, res));
849 return res;
850 }
851 static Object interpret_L(MethodHandle mh, Object x1) throws Throwable {
852 Object[] av = {mh, x1};
853 String sig = null;
854 assert(argumentTypesMatch(sig = "LL_L", av));
855 Object res = mh.form.interpretWithArguments(av);
856 assert(returnTypesMatch(sig, av, res));
857 return res;
858 }
859 static Object interpret_L(MethodHandle mh, Object x1, Object x2) throws Throwable {
860 Object[] av = {mh, x1, x2};
861 String sig = null;
862 assert(argumentTypesMatch(sig = "LLL_L", av));
863 Object res = mh.form.interpretWithArguments(av);
864 assert(returnTypesMatch(sig, av, res));
865 return res;
866 }
867
868 // The next few routines are called only from assert expressions
869 // They verify that the built-in invokers process the correct raw data types.
870 private static boolean argumentTypesMatch(String sig, Object[] av) {
871 int arity = signatureArity(sig);
872 assert(av.length == arity) : "av.length == arity: av.length=" + av.length + ", arity=" + arity;
873 assert(av[0] instanceof MethodHandle) : "av[0] not instace of MethodHandle: " + av[0];
874 MethodHandle mh = (MethodHandle) av[0];
875 MethodType mt = mh.type();
876 assert(mt.parameterCount() == arity-1);
877 for (int i = 0; i < av.length; i++) {
878 Class<?> pt = (i == 0 ? MethodHandle.class : mt.parameterType(i-1));
879 assert(valueMatches(basicType(sig.charAt(i)), pt, av[i]));
880 }
881 return true;
882 }
883 private static boolean valueMatches(BasicType tc, Class<?> type, Object x) {
884 // The following line is needed because (...)void method handles can use non-void invokers
885 if (type == void.class) tc = V_TYPE; // can drop any kind of value
886 assert tc == basicType(type) : tc + " == basicType(" + type + ")=" + basicType(type);
887 switch (tc) {
888 case I_TYPE: assert checkInt(type, x) : "checkInt(" + type + "," + x +")"; break;
889 case J_TYPE: assert x instanceof Long : "instanceof Long: " + x; break;
890 case F_TYPE: assert x instanceof Float : "instanceof Float: " + x; break;
891 case D_TYPE: assert x instanceof Double : "instanceof Double: " + x; break;
892 case L_TYPE: assert checkRef(type, x) : "checkRef(" + type + "," + x + ")"; break;
893 case V_TYPE: break; // allow anything here; will be dropped
894 default: assert(false);
895 }
896 return true;
897 }
898 private static boolean returnTypesMatch(String sig, Object[] av, Object res) {
899 MethodHandle mh = (MethodHandle) av[0];
900 return valueMatches(signatureReturn(sig), mh.type().returnType(), res);
901 }
902 private static boolean checkInt(Class<?> type, Object x) {
903 assert(x instanceof Integer);
904 if (type == int.class) return true;
905 Wrapper w = Wrapper.forBasicType(type);
906 assert(w.isSubwordOrInt());
907 Object x1 = Wrapper.INT.wrap(w.wrap(x));
908 return x.equals(x1);
909 }
910 private static boolean checkRef(Class<?> type, Object x) {
911 assert(!type.isPrimitive());
912 if (x == null) return true;
913 if (type.isInterface()) return true;
914 return type.isInstance(x);
915 }
916
917 /** If the invocation count hits the threshold we spin bytecodes and call that subsequently. */
918 private static final int COMPILE_THRESHOLD;
919 static {
920 COMPILE_THRESHOLD = Math.max(-1, MethodHandleStatics.COMPILE_THRESHOLD);
921 }
922 private int invocationCounter = 0; // a value of -1 indicates LambdaForm interpretation mode forever
923
924 private boolean forceInterpretation() {
925 return invocationCounter == -1;
926 }
927
928 @Hidden
929 @DontInline
930 /** Interpretively invoke this form on the given arguments. */
931 Object interpretWithArguments(Object... argumentValues) throws Throwable {
932 if (TRACE_INTERPRETER)
933 return interpretWithArgumentsTracing(argumentValues);
934 checkInvocationCounter();
935 assert(arityCheck(argumentValues));
936 Object[] values = Arrays.copyOf(argumentValues, names.length);
937 for (int i = argumentValues.length; i < values.length; i++) {
938 values[i] = interpretName(names[i], values);
939 }
940 Object rv = (result < 0) ? null : values[result];
941 assert(resultCheck(argumentValues, rv));
942 return rv;
943 }
944
945 @Hidden
946 @DontInline
947 /** Evaluate a single Name within this form, applying its function to its arguments. */
948 Object interpretName(Name name, Object[] values) throws Throwable {
949 if (TRACE_INTERPRETER)
950 traceInterpreter("| interpretName", name.debugString(), (Object[]) null);
951 Object[] arguments = Arrays.copyOf(name.arguments, name.arguments.length, Object[].class);
952 for (int i = 0; i < arguments.length; i++) {
953 Object a = arguments[i];
954 if (a instanceof Name) {
955 int i2 = ((Name)a).index();
956 assert(names[i2] == a);
957 a = values[i2];
958 arguments[i] = a;
959 }
960 }
961 return name.function.invokeWithArguments(arguments);
962 }
963
964 private void checkInvocationCounter() {
965 if (COMPILE_THRESHOLD != 0 &&
966 !forceInterpretation() && invocationCounter < COMPILE_THRESHOLD) {
967 invocationCounter++; // benign race
968 if (invocationCounter >= COMPILE_THRESHOLD) {
969 // Replace vmentry with a bytecode version of this LF.
970 compileToBytecode();
971 }
972 }
973 }
974 Object interpretWithArgumentsTracing(Object... argumentValues) throws Throwable {
975 traceInterpreter("[ interpretWithArguments", this, argumentValues);
976 if (!forceInterpretation() && invocationCounter < COMPILE_THRESHOLD) {
977 int ctr = invocationCounter++; // benign race
978 traceInterpreter("| invocationCounter", ctr);
979 if (invocationCounter >= COMPILE_THRESHOLD) {
980 compileToBytecode();
981 }
982 }
983 Object rval;
984 try {
985 assert(arityCheck(argumentValues));
986 Object[] values = Arrays.copyOf(argumentValues, names.length);
987 for (int i = argumentValues.length; i < values.length; i++) {
988 values[i] = interpretName(names[i], values);
989 }
990 rval = (result < 0) ? null : values[result];
991 } catch (Throwable ex) {
992 traceInterpreter("] throw =>", ex);
993 throw ex;
994 }
995 traceInterpreter("] return =>", rval);
996 return rval;
997 }
998
999 static void traceInterpreter(String event, Object obj, Object... args) {
1000 if (TRACE_INTERPRETER) {
1001 System.out.println("LFI: "+event+" "+(obj != null ? obj : "")+(args != null && args.length != 0 ? Arrays.asList(args) : ""));
1002 }
1003 }
1004 static void traceInterpreter(String event, Object obj) {
1005 traceInterpreter(event, obj, (Object[])null);
1006 }
1007 private boolean arityCheck(Object[] argumentValues) {
1008 assert(argumentValues.length == arity) : arity+"!="+Arrays.asList(argumentValues)+".length";
1009 // also check that the leading (receiver) argument is somehow bound to this LF:
1010 assert(argumentValues[0] instanceof MethodHandle) : "not MH: " + argumentValues[0];
1011 MethodHandle mh = (MethodHandle) argumentValues[0];
1012 assert(mh.internalForm() == this);
1013 // note: argument #0 could also be an interface wrapper, in the future
1014 argumentTypesMatch(basicTypeSignature(), argumentValues);
1015 return true;
1016 }
1017 private boolean resultCheck(Object[] argumentValues, Object result) {
1018 MethodHandle mh = (MethodHandle) argumentValues[0];
1019 MethodType mt = mh.type();
1020 assert(valueMatches(returnType(), mt.returnType(), result));
1021 return true;
1022 }
1023
1024 private boolean isEmpty() {
1025 if (result < 0)
1026 return (names.length == arity);
1027 else if (result == arity && names.length == arity + 1)
1028 return names[arity].isConstantZero();
1029 else
1030 return false;
1031 }
1032
1033 public String toString() {
1034 StringBuilder buf = new StringBuilder(debugName+"=Lambda(");
1035 for (int i = 0; i < names.length; i++) {
1036 if (i == arity) buf.append(")=>{");
1037 Name n = names[i];
1038 if (i >= arity) buf.append("\n ");
1039 buf.append(n.paramString());
1040 if (i < arity) {
1041 if (i+1 < arity) buf.append(",");
1042 continue;
1043 }
1044 buf.append("=").append(n.exprString());
1045 buf.append(";");
1046 }
1047 if (arity == names.length) buf.append(")=>{");
1048 buf.append(result < 0 ? "void" : names[result]).append("}");
1049 if (TRACE_INTERPRETER) {
1050 // Extra verbosity:
1051 buf.append(":").append(basicTypeSignature());
1052 buf.append("/").append(vmentry);
1053 }
1054 return buf.toString();
1055 }
1056
1057 @Override
1058 public boolean equals(Object obj) {
1059 return obj instanceof LambdaForm && equals((LambdaForm)obj);
1060 }
1061 public boolean equals(LambdaForm that) {
1062 if (this.result != that.result) return false;
1063 return Arrays.equals(this.names, that.names);
1064 }
1065 public int hashCode() {
1066 return result + 31 * Arrays.hashCode(names);
1067 }
1068 LambdaFormEditor editor() {
1069 return LambdaFormEditor.lambdaFormEditor(this);
1070 }
1071
1072 boolean contains(Name name) {
1073 int pos = name.index();
1074 if (pos >= 0) {
1075 return pos < names.length && name.equals(names[pos]);
1076 }
1077 for (int i = arity; i < names.length; i++) {
1078 if (name.equals(names[i]))
1079 return true;
1080 }
1081 return false;
1082 }
1083
1084 static class NamedFunction {
1085 final MemberName member;
1086 private @Stable MethodHandle resolvedHandle;
1087 @Stable MethodHandle invoker;
1088
1089 NamedFunction(MethodHandle resolvedHandle) {
1090 this(resolvedHandle.internalMemberName(), resolvedHandle);
1091 }
1092 NamedFunction(MemberName member, MethodHandle resolvedHandle) {
1093 this.member = member;
1094 this.resolvedHandle = resolvedHandle;
1095 // The following assert is almost always correct, but will fail for corner cases, such as PrivateInvokeTest.
1096 //assert(!isInvokeBasic(member));
1097 }
1098 NamedFunction(MethodType basicInvokerType) {
1099 assert(basicInvokerType == basicInvokerType.basicType()) : basicInvokerType;
1100 if (basicInvokerType.parameterSlotCount() < MethodType.MAX_MH_INVOKER_ARITY) {
1101 this.resolvedHandle = basicInvokerType.invokers().basicInvoker();
1102 this.member = resolvedHandle.internalMemberName();
1103 } else {
1104 // necessary to pass BigArityTest
1105 this.member = Invokers.invokeBasicMethod(basicInvokerType);
1106 }
1107 assert(isInvokeBasic(member));
1108 }
1109
1110 private static boolean isInvokeBasic(MemberName member) {
1111 return member != null &&
1112 member.getDeclaringClass() == MethodHandle.class &&
1113 "invokeBasic".equals(member.getName());
1114 }
1115
1116 // The next 2 constructors are used to break circular dependencies on MH.invokeStatic, etc.
1117 // Any LambdaForm containing such a member is not interpretable.
1118 // This is OK, since all such LFs are prepared with special primitive vmentry points.
1119 // And even without the resolvedHandle, the name can still be compiled and optimized.
1120 NamedFunction(Method method) {
1121 this(new MemberName(method));
1122 }
1123 NamedFunction(MemberName member) {
1124 this(member, null);
1125 }
1126
1127 MethodHandle resolvedHandle() {
1128 if (resolvedHandle == null) resolve();
1129 return resolvedHandle;
1130 }
1131
1132 synchronized void resolve() {
1133 if (resolvedHandle == null) {
1134 resolvedHandle = DirectMethodHandle.make(member);
1135 }
1136 }
1137
1138 @Override
1139 public boolean equals(Object other) {
1140 if (this == other) return true;
1141 if (other == null) return false;
1142 if (!(other instanceof NamedFunction)) return false;
1143 NamedFunction that = (NamedFunction) other;
1144 return this.member != null && this.member.equals(that.member);
1145 }
1146
1147 @Override
1148 public int hashCode() {
1149 if (member != null)
1150 return member.hashCode();
1151 return super.hashCode();
1152 }
1153
1154 // Put the predefined NamedFunction invokers into the table.
1155 static void initializeInvokers() {
1156 for (MemberName m : MemberName.getFactory().getMethods(NamedFunction.class, false, null, null, null)) {
1157 if (!m.isStatic() || !m.isPackage()) continue;
1158 MethodType type = m.getMethodType();
1159 if (type.equals(INVOKER_METHOD_TYPE) &&
1160 m.getName().startsWith("invoke_")) {
1161 String sig = m.getName().substring("invoke_".length());
1162 int arity = LambdaForm.signatureArity(sig);
1163 MethodType srcType = MethodType.genericMethodType(arity);
1164 if (LambdaForm.signatureReturn(sig) == V_TYPE)
1165 srcType = srcType.changeReturnType(void.class);
1166 MethodTypeForm typeForm = srcType.form();
1167 typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, DirectMethodHandle.make(m));
1168 }
1169 }
1170 }
1171
1172 // The following are predefined NamedFunction invokers. The system must build
1173 // a separate invoker for each distinct signature.
1174 /** void return type invokers. */
1175 @Hidden
1176 static Object invoke__V(MethodHandle mh, Object[] a) throws Throwable {
1177 assert(arityCheck(0, void.class, mh, a));
1178 mh.invokeBasic();
1179 return null;
1180 }
1181 @Hidden
1182 static Object invoke_L_V(MethodHandle mh, Object[] a) throws Throwable {
1183 assert(arityCheck(1, void.class, mh, a));
1184 mh.invokeBasic(a[0]);
1185 return null;
1186 }
1187 @Hidden
1188 static Object invoke_LL_V(MethodHandle mh, Object[] a) throws Throwable {
1189 assert(arityCheck(2, void.class, mh, a));
1190 mh.invokeBasic(a[0], a[1]);
1191 return null;
1192 }
1193 @Hidden
1194 static Object invoke_LLL_V(MethodHandle mh, Object[] a) throws Throwable {
1195 assert(arityCheck(3, void.class, mh, a));
1196 mh.invokeBasic(a[0], a[1], a[2]);
1197 return null;
1198 }
1199 @Hidden
1200 static Object invoke_LLLL_V(MethodHandle mh, Object[] a) throws Throwable {
1201 assert(arityCheck(4, void.class, mh, a));
1202 mh.invokeBasic(a[0], a[1], a[2], a[3]);
1203 return null;
1204 }
1205 @Hidden
1206 static Object invoke_LLLLL_V(MethodHandle mh, Object[] a) throws Throwable {
1207 assert(arityCheck(5, void.class, mh, a));
1208 mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
1209 return null;
1210 }
1211 /** Object return type invokers. */
1212 @Hidden
1213 static Object invoke__L(MethodHandle mh, Object[] a) throws Throwable {
1214 assert(arityCheck(0, mh, a));
1215 return mh.invokeBasic();
1216 }
1217 @Hidden
1218 static Object invoke_L_L(MethodHandle mh, Object[] a) throws Throwable {
1219 assert(arityCheck(1, mh, a));
1220 return mh.invokeBasic(a[0]);
1221 }
1222 @Hidden
1223 static Object invoke_LL_L(MethodHandle mh, Object[] a) throws Throwable {
1224 assert(arityCheck(2, mh, a));
1225 return mh.invokeBasic(a[0], a[1]);
1226 }
1227 @Hidden
1228 static Object invoke_LLL_L(MethodHandle mh, Object[] a) throws Throwable {
1229 assert(arityCheck(3, mh, a));
1230 return mh.invokeBasic(a[0], a[1], a[2]);
1231 }
1232 @Hidden
1233 static Object invoke_LLLL_L(MethodHandle mh, Object[] a) throws Throwable {
1234 assert(arityCheck(4, mh, a));
1235 return mh.invokeBasic(a[0], a[1], a[2], a[3]);
1236 }
1237 @Hidden
1238 static Object invoke_LLLLL_L(MethodHandle mh, Object[] a) throws Throwable {
1239 assert(arityCheck(5, mh, a));
1240 return mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
1241 }
1242 private static boolean arityCheck(int arity, MethodHandle mh, Object[] a) {
1243 return arityCheck(arity, Object.class, mh, a);
1244 }
1245 private static boolean arityCheck(int arity, Class<?> rtype, MethodHandle mh, Object[] a) {
1246 assert(a.length == arity)
1247 : Arrays.asList(a.length, arity);
1248 assert(mh.type().basicType() == MethodType.genericMethodType(arity).changeReturnType(rtype))
1249 : Arrays.asList(mh, rtype, arity);
1250 MemberName member = mh.internalMemberName();
1251 if (isInvokeBasic(member)) {
1252 assert(arity > 0);
1253 assert(a[0] instanceof MethodHandle);
1254 MethodHandle mh2 = (MethodHandle) a[0];
1255 assert(mh2.type().basicType() == MethodType.genericMethodType(arity-1).changeReturnType(rtype))
1256 : Arrays.asList(member, mh2, rtype, arity);
1257 }
1258 return true;
1259 }
1260
1261 static final MethodType INVOKER_METHOD_TYPE =
1262 MethodType.methodType(Object.class, MethodHandle.class, Object[].class);
1263
1264 private static MethodHandle computeInvoker(MethodTypeForm typeForm) {
1265 typeForm = typeForm.basicType().form(); // normalize to basic type
1266 MethodHandle mh = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV);
1267 if (mh != null) return mh;
1268 MemberName invoker = InvokerBytecodeGenerator.generateNamedFunctionInvoker(typeForm); // this could take a while
1269 mh = DirectMethodHandle.make(invoker);
1270 MethodHandle mh2 = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV);
1271 if (mh2 != null) return mh2; // benign race
1272 if (!mh.type().equals(INVOKER_METHOD_TYPE))
1273 throw newInternalError(mh.debugString());
1274 return typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, mh);
1275 }
1276
1277 @Hidden
1278 Object invokeWithArguments(Object... arguments) throws Throwable {
1279 // If we have a cached invoker, call it right away.
1280 // NOTE: The invoker always returns a reference value.
1281 if (TRACE_INTERPRETER) return invokeWithArgumentsTracing(arguments);
1282 assert(checkArgumentTypes(arguments, methodType()));
1283 return invoker().invokeBasic(resolvedHandle(), arguments);
1284 }
1285
1286 @Hidden
1287 Object invokeWithArgumentsTracing(Object[] arguments) throws Throwable {
1288 Object rval;
1289 try {
1290 traceInterpreter("[ call", this, arguments);
1291 if (invoker == null) {
1292 traceInterpreter("| getInvoker", this);
1293 invoker();
1294 }
1295 // resolvedHandle might be uninitialized, ok for tracing
1296 if (resolvedHandle == null) {
1297 traceInterpreter("| resolve", this);
1298 resolvedHandle();
1299 }
1300 assert(checkArgumentTypes(arguments, methodType()));
1301 rval = invoker().invokeBasic(resolvedHandle(), arguments);
1302 } catch (Throwable ex) {
1303 traceInterpreter("] throw =>", ex);
1304 throw ex;
1305 }
1306 traceInterpreter("] return =>", rval);
1307 return rval;
1308 }
1309
1310 private MethodHandle invoker() {
1311 if (invoker != null) return invoker;
1312 // Get an invoker and cache it.
1313 return invoker = computeInvoker(methodType().form());
1314 }
1315
1316 private static boolean checkArgumentTypes(Object[] arguments, MethodType methodType) {
1317 if (true) return true; // FIXME
1318 MethodType dstType = methodType.form().erasedType();
1319 MethodType srcType = dstType.basicType().wrap();
1320 Class<?>[] ptypes = new Class<?>[arguments.length];
1321 for (int i = 0; i < arguments.length; i++) {
1322 Object arg = arguments[i];
1323 Class<?> ptype = arg == null ? Object.class : arg.getClass();
1324 // If the dest. type is a primitive we keep the
1325 // argument type.
1326 ptypes[i] = dstType.parameterType(i).isPrimitive() ? ptype : Object.class;
1327 }
1328 MethodType argType = MethodType.methodType(srcType.returnType(), ptypes).wrap();
1329 assert(argType.isConvertibleTo(srcType)) : "wrong argument types: cannot convert " + argType + " to " + srcType;
1330 return true;
1331 }
1332
1333 MethodType methodType() {
1334 if (resolvedHandle != null)
1335 return resolvedHandle.type();
1336 else
1337 // only for certain internal LFs during bootstrapping
1338 return member.getInvocationType();
1339 }
1340
1341 MemberName member() {
1342 assert(assertMemberIsConsistent());
1343 return member;
1344 }
1345
1346 // Called only from assert.
1347 private boolean assertMemberIsConsistent() {
1348 if (resolvedHandle instanceof DirectMethodHandle) {
1349 MemberName m = resolvedHandle.internalMemberName();
1350 assert(m.equals(member));
1351 }
1352 return true;
1353 }
1354
1355 Class<?> memberDeclaringClassOrNull() {
1356 return (member == null) ? null : member.getDeclaringClass();
1357 }
1358
1359 BasicType returnType() {
1360 return basicType(methodType().returnType());
1361 }
1362
1363 BasicType parameterType(int n) {
1364 return basicType(methodType().parameterType(n));
1365 }
1366
1367 int arity() {
1368 return methodType().parameterCount();
1369 }
1370
1371 public String toString() {
1372 if (member == null) return String.valueOf(resolvedHandle);
1373 return member.getDeclaringClass().getSimpleName()+"."+member.getName();
1374 }
1375
1376 public boolean isIdentity() {
1377 return this.equals(identity(returnType()));
1378 }
1379
1380 public boolean isConstantZero() {
1381 return this.equals(constantZero(returnType()));
1382 }
1383
1384 public MethodHandleImpl.Intrinsic intrinsicName() {
1385 return resolvedHandle == null ? MethodHandleImpl.Intrinsic.NONE
1386 : resolvedHandle.intrinsicName();
1387 }
1388 }
1389
1390 public static String basicTypeSignature(MethodType type) {
1391 int params = type.parameterCount();
1392 char[] sig = new char[params + 2];
1393 int sigp = 0;
1394 while (sigp < params) {
1395 sig[sigp] = basicTypeChar(type.parameterType(sigp++));
1396 }
1397 sig[sigp++] = '_';
1398 sig[sigp++] = basicTypeChar(type.returnType());
1399 assert(sigp == sig.length);
1400 return String.valueOf(sig);
1401 }
1402 public static String shortenSignature(String signature) {
1403 // Hack to make signatures more readable when they show up in method names.
1404 final int NO_CHAR = -1, MIN_RUN = 3;
1405 int c0, c1 = NO_CHAR, c1reps = 0;
1406 StringBuilder buf = null;
1407 int len = signature.length();
1408 if (len < MIN_RUN) return signature;
1409 for (int i = 0; i <= len; i++) {
1410 // shift in the next char:
1411 c0 = c1; c1 = (i == len ? NO_CHAR : signature.charAt(i));
1412 if (c1 == c0) { ++c1reps; continue; }
1413 // shift in the next count:
1414 int c0reps = c1reps; c1reps = 1;
1415 // end of a character run
1416 if (c0reps < MIN_RUN) {
1417 if (buf != null) {
1418 while (--c0reps >= 0)
1419 buf.append((char)c0);
1420 }
1421 continue;
1422 }
1423 // found three or more in a row
1424 if (buf == null)
1425 buf = new StringBuilder().append(signature, 0, i - c0reps);
1426 buf.append((char)c0).append(c0reps);
1427 }
1428 return (buf == null) ? signature : buf.toString();
1429 }
1430
1431 static final class Name {
1432 final BasicType type;
1433 @Stable short index;
1434 final NamedFunction function;
1435 final Object constraint; // additional type information, if not null
1436 @Stable final Object[] arguments;
1437
1438 private Name(int index, BasicType type, NamedFunction function, Object[] arguments) {
1439 this.index = (short)index;
1440 this.type = type;
1441 this.function = function;
1442 this.arguments = arguments;
1443 this.constraint = null;
1444 assert(this.index == index);
1445 }
1446 private Name(Name that, Object constraint) {
1447 this.index = that.index;
1448 this.type = that.type;
1449 this.function = that.function;
1450 this.arguments = that.arguments;
1451 this.constraint = constraint;
1452 assert(constraint == null || isParam()); // only params have constraints
1453 assert(constraint == null || constraint instanceof BoundMethodHandle.SpeciesData || constraint instanceof Class);
1454 }
1455 Name(MethodHandle function, Object... arguments) {
1456 this(new NamedFunction(function), arguments);
1457 }
1458 Name(MethodType functionType, Object... arguments) {
1459 this(new NamedFunction(functionType), arguments);
1460 assert(arguments[0] instanceof Name && ((Name)arguments[0]).type == L_TYPE);
1461 }
1462 Name(MemberName function, Object... arguments) {
1463 this(new NamedFunction(function), arguments);
1464 }
1465 Name(NamedFunction function, Object... arguments) {
1466 this(-1, function.returnType(), function, arguments = Arrays.copyOf(arguments, arguments.length, Object[].class));
1467 assert(typesMatch(function, arguments));
1468 }
1469 /** Create a raw parameter of the given type, with an expected index. */
1470 Name(int index, BasicType type) {
1471 this(index, type, null, null);
1472 }
1473 /** Create a raw parameter of the given type. */
1474 Name(BasicType type) { this(-1, type); }
1475
1476 BasicType type() { return type; }
1477 int index() { return index; }
1478 boolean initIndex(int i) {
1479 if (index != i) {
1480 if (index != -1) return false;
1481 index = (short)i;
1482 }
1483 return true;
1484 }
1485 char typeChar() {
1486 return type.btChar;
1487 }
1488
1489 void resolve() {
1490 if (function != null)
1491 function.resolve();
1492 }
1493
1494 Name newIndex(int i) {
1495 if (initIndex(i)) return this;
1496 return cloneWithIndex(i);
1497 }
1498 Name cloneWithIndex(int i) {
1499 Object[] newArguments = (arguments == null) ? null : arguments.clone();
1500 return new Name(i, type, function, newArguments).withConstraint(constraint);
1501 }
1502 Name withConstraint(Object constraint) {
1503 if (constraint == this.constraint) return this;
1504 return new Name(this, constraint);
1505 }
1506 Name replaceName(Name oldName, Name newName) { // FIXME: use replaceNames uniformly
1507 if (oldName == newName) return this;
1508 @SuppressWarnings("LocalVariableHidesMemberVariable")
1509 Object[] arguments = this.arguments;
1510 if (arguments == null) return this;
1511 boolean replaced = false;
1512 for (int j = 0; j < arguments.length; j++) {
1513 if (arguments[j] == oldName) {
1514 if (!replaced) {
1515 replaced = true;
1516 arguments = arguments.clone();
1517 }
1518 arguments[j] = newName;
1519 }
1520 }
1521 if (!replaced) return this;
1522 return new Name(function, arguments);
1523 }
1524 /** In the arguments of this Name, replace oldNames[i] pairwise by newNames[i].
1525 * Limit such replacements to {@code start<=i<end}. Return possibly changed self.
1526 */
1527 Name replaceNames(Name[] oldNames, Name[] newNames, int start, int end) {
1528 if (start >= end) return this;
1529 @SuppressWarnings("LocalVariableHidesMemberVariable")
1530 Object[] arguments = this.arguments;
1531 boolean replaced = false;
1532 eachArg:
1533 for (int j = 0; j < arguments.length; j++) {
1534 if (arguments[j] instanceof Name) {
1535 Name n = (Name) arguments[j];
1536 int check = n.index;
1537 // harmless check to see if the thing is already in newNames:
1538 if (check >= 0 && check < newNames.length && n == newNames[check])
1539 continue eachArg;
1540 // n might not have the correct index: n != oldNames[n.index].
1541 for (int i = start; i < end; i++) {
1542 if (n == oldNames[i]) {
1543 if (n == newNames[i])
1544 continue eachArg;
1545 if (!replaced) {
1546 replaced = true;
1547 arguments = arguments.clone();
1548 }
1549 arguments[j] = newNames[i];
1550 continue eachArg;
1551 }
1552 }
1553 }
1554 }
1555 if (!replaced) return this;
1556 return new Name(function, arguments);
1557 }
1558 void internArguments() {
1559 @SuppressWarnings("LocalVariableHidesMemberVariable")
1560 Object[] arguments = this.arguments;
1561 for (int j = 0; j < arguments.length; j++) {
1562 if (arguments[j] instanceof Name) {
1563 Name n = (Name) arguments[j];
1564 if (n.isParam() && n.index < INTERNED_ARGUMENT_LIMIT)
1565 arguments[j] = internArgument(n);
1566 }
1567 }
1568 }
1569 boolean isParam() {
1570 return function == null;
1571 }
1572 boolean isConstantZero() {
1573 return !isParam() && arguments.length == 0 && function.isConstantZero();
1574 }
1575
1576 boolean refersTo(Class<?> declaringClass, String methodName) {
1577 return function != null &&
1578 function.member() != null && function.member().refersTo(declaringClass, methodName);
1579 }
1580
1581 /**
1582 * Check if MemberName is a call to MethodHandle.invokeBasic.
1583 */
1584 boolean isInvokeBasic() {
1585 if (function == null)
1586 return false;
1587 if (arguments.length < 1)
1588 return false; // must have MH argument
1589 MemberName member = function.member();
1590 return member != null && member.refersTo(MethodHandle.class, "invokeBasic") &&
1591 !member.isPublic() && !member.isStatic();
1592 }
1593
1594 /**
1595 * Check if MemberName is a call to MethodHandle.linkToStatic, etc.
1596 */
1597 boolean isLinkerMethodInvoke() {
1598 if (function == null)
1599 return false;
1600 if (arguments.length < 1)
1601 return false; // must have MH argument
1602 MemberName member = function.member();
1603 return member != null &&
1604 member.getDeclaringClass() == MethodHandle.class &&
1605 !member.isPublic() && member.isStatic() &&
1606 member.getName().startsWith("linkTo");
1607 }
1608
1609 public String toString() {
1610 return (isParam()?"a":"t")+(index >= 0 ? index : System.identityHashCode(this))+":"+typeChar();
1611 }
1612 public String debugString() {
1613 String s = paramString();
1614 return (function == null) ? s : s + "=" + exprString();
1615 }
1616 public String paramString() {
1617 String s = toString();
1618 Object c = constraint;
1619 if (c == null)
1620 return s;
1621 if (c instanceof Class) c = ((Class<?>)c).getSimpleName();
1622 return s + "/" + c;
1623 }
1624 public String exprString() {
1625 if (function == null) return toString();
1626 StringBuilder buf = new StringBuilder(function.toString());
1627 buf.append("(");
1628 String cma = "";
1629 for (Object a : arguments) {
1630 buf.append(cma); cma = ",";
1631 if (a instanceof Name || a instanceof Integer)
1632 buf.append(a);
1633 else
1634 buf.append("(").append(a).append(")");
1635 }
1636 buf.append(")");
1637 return buf.toString();
1638 }
1639
1640 private boolean typesMatch(NamedFunction function, Object ... arguments) {
1641 assert(arguments.length == function.arity()) : "arity mismatch: arguments.length=" + arguments.length + " == function.arity()=" + function.arity() + " in " + debugString();
1642 for (int i = 0; i < arguments.length; i++) {
1643 assert (typesMatch(function.parameterType(i), arguments[i])) : "types don't match: function.parameterType(" + i + ")=" + function.parameterType(i) + ", arguments[" + i + "]=" + arguments[i] + " in " + debugString();
1644 }
1645 return true;
1646 }
1647
1648 private static boolean typesMatch(BasicType parameterType, Object object) {
1649 if (object instanceof Name) {
1650 return ((Name)object).type == parameterType;
1651 }
1652 switch (parameterType) {
1653 case I_TYPE: return object instanceof Integer;
1654 case J_TYPE: return object instanceof Long;
1655 case F_TYPE: return object instanceof Float;
1656 case D_TYPE: return object instanceof Double;
1657 }
1658 assert(parameterType == L_TYPE);
1659 return true;
1660 }
1661
1662 /** Return the index of the last occurrence of n in the argument array.
1663 * Return -1 if the name is not used.
1664 */
1665 int lastUseIndex(Name n) {
1666 if (arguments == null) return -1;
1667 for (int i = arguments.length; --i >= 0; ) {
1668 if (arguments[i] == n) return i;
1669 }
1670 return -1;
1671 }
1672
1673 /** Return the number of occurrences of n in the argument array.
1674 * Return 0 if the name is not used.
1675 */
1676 int useCount(Name n) {
1677 if (arguments == null) return 0;
1678 int count = 0;
1679 for (int i = arguments.length; --i >= 0; ) {
1680 if (arguments[i] == n) ++count;
1681 }
1682 return count;
1683 }
1684
1685 boolean contains(Name n) {
1686 return this == n || lastUseIndex(n) >= 0;
1687 }
1688
1689 public boolean equals(Name that) {
1690 if (this == that) return true;
1691 if (isParam())
1692 // each parameter is a unique atom
1693 return false; // this != that
1694 return
1695 //this.index == that.index &&
1696 this.type == that.type &&
1697 this.function.equals(that.function) &&
1698 Arrays.equals(this.arguments, that.arguments);
1699 }
1700 @Override
1701 public boolean equals(Object x) {
1702 return x instanceof Name && equals((Name)x);
1703 }
1704 @Override
1705 public int hashCode() {
1706 if (isParam())
1707 return index | (type.ordinal() << 8);
1708 return function.hashCode() ^ Arrays.hashCode(arguments);
1709 }
1710 }
1711
1712 /** Return the index of the last name which contains n as an argument.
1713 * Return -1 if the name is not used. Return names.length if it is the return value.
1714 */
1715 int lastUseIndex(Name n) {
1716 int ni = n.index, nmax = names.length;
1717 assert(names[ni] == n);
1718 if (result == ni) return nmax; // live all the way beyond the end
1719 for (int i = nmax; --i > ni; ) {
1720 if (names[i].lastUseIndex(n) >= 0)
1721 return i;
1722 }
1723 return -1;
1724 }
1725
1726 /** Return the number of times n is used as an argument or return value. */
1727 int useCount(Name n) {
1728 int nmax = names.length;
1729 int end = lastUseIndex(n);
1730 if (end < 0) return 0;
1731 int count = 0;
1732 if (end == nmax) { count++; end--; }
1733 int beg = n.index() + 1;
1734 if (beg < arity) beg = arity;
1735 for (int i = beg; i <= end; i++) {
1736 count += names[i].useCount(n);
1737 }
1738 return count;
1739 }
1740
1741 static Name argument(int which, BasicType type) {
1742 if (which >= INTERNED_ARGUMENT_LIMIT)
1743 return new Name(which, type);
1744 return INTERNED_ARGUMENTS[type.ordinal()][which];
1745 }
1746 static Name internArgument(Name n) {
1747 assert(n.isParam()) : "not param: " + n;
1748 assert(n.index < INTERNED_ARGUMENT_LIMIT);
1749 if (n.constraint != null) return n;
1750 return argument(n.index, n.type);
1751 }
1752 static Name[] arguments(int extra, MethodType types) {
1753 int length = types.parameterCount();
1754 Name[] names = new Name[length + extra];
1755 for (int i = 0; i < length; i++)
1756 names[i] = argument(i, basicType(types.parameterType(i)));
1757 return names;
1758 }
1759 static final int INTERNED_ARGUMENT_LIMIT = 10;
1760 private static final Name[][] INTERNED_ARGUMENTS
1761 = new Name[ARG_TYPE_LIMIT][INTERNED_ARGUMENT_LIMIT];
1762 static {
1763 for (BasicType type : BasicType.ARG_TYPES) {
1764 int ord = type.ordinal();
1765 for (int i = 0; i < INTERNED_ARGUMENTS[ord].length; i++) {
1766 INTERNED_ARGUMENTS[ord][i] = new Name(i, type);
1767 }
1768 }
1769 }
1770
1771 private static final MemberName.Factory IMPL_NAMES = MemberName.getFactory();
1772
1773 static LambdaForm identityForm(BasicType type) {
1774 int ord = type.ordinal();
1775 LambdaForm form = LF_identity[ord];
1776 if (form != null) {
1777 return form;
1778 }
1779 createFormsFor(type);
1780 return LF_identity[ord];
1781 }
1782
1783 static LambdaForm zeroForm(BasicType type) {
1784 int ord = type.ordinal();
1785 LambdaForm form = LF_zero[ord];
1786 if (form != null) {
1787 return form;
1788 }
1789 createFormsFor(type);
1790 return LF_zero[ord];
1791 }
1792
1793 static NamedFunction identity(BasicType type) {
1794 int ord = type.ordinal();
1795 NamedFunction function = NF_identity[ord];
1796 if (function != null) {
1797 return function;
1798 }
1799 createFormsFor(type);
1800 return NF_identity[ord];
1801 }
1802
1803 static NamedFunction constantZero(BasicType type) {
1804 int ord = type.ordinal();
1805 NamedFunction function = NF_zero[ord];
1806 if (function != null) {
1807 return function;
1808 }
1809 createFormsFor(type);
1810 return NF_zero[ord];
1811 }
1812
1813 private static final @Stable LambdaForm[] LF_identity = new LambdaForm[TYPE_LIMIT];
1814 private static final @Stable LambdaForm[] LF_zero = new LambdaForm[TYPE_LIMIT];
1815 private static final @Stable NamedFunction[] NF_identity = new NamedFunction[TYPE_LIMIT];
1816 private static final @Stable NamedFunction[] NF_zero = new NamedFunction[TYPE_LIMIT];
1817
1818 private static synchronized void createFormsFor(BasicType type) {
1819 final int ord = type.ordinal();
1820 LambdaForm idForm = LF_identity[ord];
1821 if (idForm != null) {
1822 return;
1823 }
1824 char btChar = type.basicTypeChar();
1825 boolean isVoid = (type == V_TYPE);
1826 Class<?> btClass = type.btClass;
1827 MethodType zeType = MethodType.methodType(btClass);
1828 MethodType idType = (isVoid) ? zeType : zeType.appendParameterTypes(btClass);
1829
1830 // Look up symbolic names. It might not be necessary to have these,
1831 // but if we need to emit direct references to bytecodes, it helps.
1832 // Zero is built from a call to an identity function with a constant zero input.
1833 MemberName idMem = new MemberName(LambdaForm.class, "identity_"+btChar, idType, REF_invokeStatic);
1834 MemberName zeMem = null;
1835 try {
1836 idMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, idMem, null, NoSuchMethodException.class);
1837 if (!isVoid) {
1838 zeMem = new MemberName(LambdaForm.class, "zero_"+btChar, zeType, REF_invokeStatic);
1839 zeMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, zeMem, null, NoSuchMethodException.class);
1840 }
1841 } catch (IllegalAccessException|NoSuchMethodException ex) {
1842 throw newInternalError(ex);
1843 }
1844
1845 NamedFunction idFun;
1846 LambdaForm zeForm;
1847 NamedFunction zeFun;
1848
1849 // Create the LFs and NamedFunctions. Precompiling LFs to byte code is needed to break circular
1850 // bootstrap dependency on this method in case we're interpreting LFs
1851 if (isVoid) {
1852 Name[] idNames = new Name[] { argument(0, L_TYPE) };
1853 idForm = new LambdaForm(idMem.getName(), 1, idNames, VOID_RESULT, Kind.IDENTITY);
1854 idForm.compileToBytecode();
1855 idFun = new NamedFunction(idMem, SimpleMethodHandle.make(idMem.getInvocationType(), idForm));
1856
1857 zeForm = idForm;
1858 zeFun = idFun;
1859 } else {
1860 Name[] idNames = new Name[] { argument(0, L_TYPE), argument(1, type) };
1861 idForm = new LambdaForm(idMem.getName(), 2, idNames, 1, Kind.IDENTITY);
1862 idForm.compileToBytecode();
1863 idFun = new NamedFunction(idMem, MethodHandleImpl.makeIntrinsic(
1864 idMem.getInvocationType(), idForm, MethodHandleImpl.Intrinsic.IDENTITY));
1865
1866 Object zeValue = Wrapper.forBasicType(btChar).zero();
1867 Name[] zeNames = new Name[] { argument(0, L_TYPE), new Name(idFun, zeValue) };
1868 zeForm = new LambdaForm(zeMem.getName(), 1, zeNames, 1, Kind.ZERO);
1869 zeForm.compileToBytecode();
1870 zeFun = new NamedFunction(zeMem, MethodHandleImpl.makeIntrinsic(
1871 zeMem.getInvocationType(), zeForm, MethodHandleImpl.Intrinsic.ZERO));
1872 }
1873
1874 LF_zero[ord] = zeForm;
1875 NF_zero[ord] = zeFun;
1876 LF_identity[ord] = idForm;
1877 NF_identity[ord] = idFun;
1878
1879 assert(idFun.isIdentity());
1880 assert(zeFun.isConstantZero());
1881 assert(new Name(zeFun).isConstantZero());
1882 }
1883
1884 // Avoid appealing to ValueConversions at bootstrap time:
1885 private static int identity_I(int x) { return x; }
1886 private static long identity_J(long x) { return x; }
1887 private static float identity_F(float x) { return x; }
1888 private static double identity_D(double x) { return x; }
1889 private static Object identity_L(Object x) { return x; }
1890 private static void identity_V() { return; }
1891 private static int zero_I() { return 0; }
1892 private static long zero_J() { return 0; }
1893 private static float zero_F() { return 0; }
1894 private static double zero_D() { return 0; }
1895 private static Object zero_L() { return null; }
1896
1897 /**
1898 * Internal marker for byte-compiled LambdaForms.
1899 */
1900 /*non-public*/
1901 @Target(ElementType.METHOD)
1902 @Retention(RetentionPolicy.RUNTIME)
1903 @interface Compiled {
1904 }
1905
1906 /**
1907 * Internal marker for LambdaForm interpreter frames.
1908 */
1909 /*non-public*/
1910 @Target(ElementType.METHOD)
1911 @Retention(RetentionPolicy.RUNTIME)
1912 @interface Hidden {
1913 }
1914
1915 private static final HashMap<String,Integer> DEBUG_NAME_COUNTERS;
1916 static {
1917 if (debugEnabled())
1918 DEBUG_NAME_COUNTERS = new HashMap<>();
1919 else
1920 DEBUG_NAME_COUNTERS = null;
1921 }
1922
1923 // Put this last, so that previous static inits can run before.
1924 static {
1925 if (USE_PREDEFINED_INTERPRET_METHODS)
1926 computeInitialPreparedForms();
1927 NamedFunction.initializeInvokers();
1928
1929 // The Holder class will contain pre-generated forms resolved
1930 // using MemberName.getFactory(). However, that doesn't initialize the
1931 // class, which subtly breaks inlining etc. By forcing
1932 // initialization of the Holder class we avoid these issues.
1933 UNSAFE.ensureClassInitialized(Holder.class);
1934 }
1935
1936 /* Placeholder class for zero and identity forms generated ahead of time */
1937 final class Holder {}
1938
1939 // The following hack is necessary in order to suppress TRACE_INTERPRETER
1940 // during execution of the static initializes of this class.
1941 // Turning on TRACE_INTERPRETER too early will cause
1942 // stack overflows and other misbehavior during attempts to trace events
1943 // that occur during LambdaForm.<clinit>.
1944 // Therefore, do not move this line higher in this file, and do not remove.
1945 private static final boolean TRACE_INTERPRETER = MethodHandleStatics.TRACE_INTERPRETER;
1946 }