1 /*
2 * Copyright (c) 2020, 2023, 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 package jdk.internal.foreign.abi;
26
27 import jdk.internal.access.JavaLangAccess;
28 import jdk.internal.access.JavaLangInvokeAccess;
29 import jdk.internal.access.SharedSecrets;
30 import jdk.internal.foreign.CABI;
31 import jdk.internal.foreign.abi.AbstractLinker.UpcallStubFactory;
32 import jdk.internal.foreign.abi.aarch64.linux.LinuxAArch64Linker;
33 import jdk.internal.foreign.abi.aarch64.macos.MacOsAArch64Linker;
34 import jdk.internal.foreign.abi.aarch64.windows.WindowsAArch64Linker;
35 import jdk.internal.foreign.abi.fallback.FallbackLinker;
36 import jdk.internal.foreign.abi.ppc64.linux.LinuxPPC64Linker;
37 import jdk.internal.foreign.abi.ppc64.linux.LinuxPPC64leLinker;
38 import jdk.internal.foreign.abi.riscv64.linux.LinuxRISCV64Linker;
39 import jdk.internal.foreign.abi.s390.linux.LinuxS390Linker;
40 import jdk.internal.foreign.abi.x64.sysv.SysVx64Linker;
41 import jdk.internal.foreign.abi.x64.windows.Windowsx64Linker;
42 import jdk.internal.vm.annotation.ForceInline;
43
44 import java.lang.foreign.AddressLayout;
45 import java.lang.foreign.Arena;
46 import java.lang.foreign.Linker;
47 import java.lang.foreign.FunctionDescriptor;
48 import java.lang.foreign.GroupLayout;
49 import java.lang.foreign.MemoryLayout;
50 import java.lang.foreign.MemorySegment;
51 import java.lang.foreign.MemorySegment.Scope;
52 import java.lang.foreign.SegmentAllocator;
53 import java.lang.foreign.ValueLayout;
54 import java.lang.invoke.MethodHandle;
55 import java.lang.invoke.MethodHandles;
56 import java.lang.invoke.MethodType;
57 import java.lang.invoke.VarHandle;
58 import java.lang.ref.Reference;
59 import java.nio.ByteOrder;
60 import java.nio.charset.StandardCharsets;
61 import java.util.Arrays;
62 import java.util.Map;
63 import java.util.Objects;
64 import java.util.stream.Collectors;
65 import java.util.stream.IntStream;
66
67 import static java.lang.foreign.ValueLayout.*;
68 import static java.lang.invoke.MethodHandles.*;
69 import static java.lang.invoke.MethodType.methodType;
70
71 public final class SharedUtils {
72
73 private SharedUtils() {
74 }
75
76 private static final JavaLangAccess JLA = SharedSecrets.getJavaLangAccess();
77 private static final JavaLangInvokeAccess JLIA = SharedSecrets.getJavaLangInvokeAccess();
78
79 private static final MethodHandle MH_ALLOC_BUFFER;
80 private static final MethodHandle MH_BUFFER_COPY;
81 private static final MethodHandle MH_REACHABILITY_FENCE;
82 public static final MethodHandle MH_CHECK_SYMBOL;
83 private static final MethodHandle MH_CHECK_CAPTURE_SEGMENT;
84
85 public static final AddressLayout C_POINTER = ADDRESS
86 .withTargetLayout(MemoryLayout.sequenceLayout(JAVA_BYTE));
87
88 public static final Arena DUMMY_ARENA = new Arena() {
89 @Override
90 public Scope scope() {
91 throw new UnsupportedOperationException();
92 }
93
94 @Override
95 public MemorySegment allocate(long byteSize) {
96 throw new UnsupportedOperationException();
97 }
98
99 @Override
100 public void close() {
101 // do nothing
102 }
103 };
104
105 static {
106 try {
107 MethodHandles.Lookup lookup = MethodHandles.lookup();
108 MH_ALLOC_BUFFER = lookup.findVirtual(SegmentAllocator.class, "allocate",
109 methodType(MemorySegment.class, MemoryLayout.class));
110 MH_BUFFER_COPY = lookup.findStatic(SharedUtils.class, "bufferCopy",
111 methodType(MemorySegment.class, MemorySegment.class, MemorySegment.class));
112 MH_REACHABILITY_FENCE = lookup.findStatic(Reference.class, "reachabilityFence",
113 methodType(void.class, Object.class));
114 MH_CHECK_SYMBOL = lookup.findStatic(SharedUtils.class, "checkSymbol",
115 methodType(void.class, MemorySegment.class));
116 MH_CHECK_CAPTURE_SEGMENT = lookup.findStatic(SharedUtils.class, "checkCaptureSegment",
117 methodType(MemorySegment.class, MemorySegment.class));
118 } catch (ReflectiveOperationException e) {
119 throw new BootstrapMethodError(e);
120 }
121 }
122
123 // this allocator should be used when no allocation is expected
124 public static final SegmentAllocator THROWING_ALLOCATOR = (size, align) -> {
125 throw new IllegalStateException("Cannot get here");
126 };
127
128 public static long alignUp(long addr, long alignment) {
129 return ((addr - 1) | (alignment - 1)) + 1;
130 }
131
132 /**
133 * Takes a MethodHandle that takes an input buffer as a first argument (a MemorySegment), and returns nothing,
134 * and adapts it to return a MemorySegment, by allocating a MemorySegment for the input
135 * buffer, calling the target MethodHandle, and then returning the allocated MemorySegment.
136 *
137 * This allows viewing a MethodHandle that makes use of in memory return (IMR) as a MethodHandle that just returns
138 * a MemorySegment without requiring a pre-allocated buffer as an explicit input.
139 *
140 * @param handle the target handle to adapt
141 * @param cDesc the function descriptor of the native function (with actual return layout)
142 * @return the adapted handle
143 */
144 public static MethodHandle adaptDowncallForIMR(MethodHandle handle, FunctionDescriptor cDesc, CallingSequence sequence) {
145 if (handle.type().returnType() != void.class)
146 throw new IllegalArgumentException("return expected to be void for in memory returns: " + handle.type());
147 int imrAddrIdx = sequence.numLeadingParams();
148 if (handle.type().parameterType(imrAddrIdx) != MemorySegment.class)
149 throw new IllegalArgumentException("MemorySegment expected as third param: " + handle.type());
150 if (cDesc.returnLayout().isEmpty())
151 throw new IllegalArgumentException("Return layout needed: " + cDesc);
152
153 MethodHandle ret = identity(MemorySegment.class); // (MemorySegment) MemorySegment
154 handle = collectArguments(ret, 1, handle); // (MemorySegment, MemorySegment, SegmentAllocator, MemorySegment, ...) MemorySegment
155 handle = mergeArguments(handle, 0, 1 + imrAddrIdx); // (MemorySegment, MemorySegment, SegmentAllocator, ...) MemorySegment
156 handle = collectArguments(handle, 0, insertArguments(MH_ALLOC_BUFFER, 1, cDesc.returnLayout().get())); // (SegmentAllocator, MemorySegment, SegmentAllocator, ...) MemorySegment
157 handle = mergeArguments(handle, 0, 2); // (SegmentAllocator, MemorySegment, ...) MemorySegment
158 handle = swapArguments(handle, 0, 1); // (MemorySegment, SegmentAllocator, ...) MemorySegment
159 return handle;
160 }
161
162 /**
163 * Takes a MethodHandle that returns a MemorySegment, and adapts it to take an input buffer as a first argument
164 * (a MemorySegment), and upon invocation, copies the contents of the returned MemorySegment into the input buffer
165 * passed as the first argument.
166 *
167 * @param target the target handle to adapt
168 * @return the adapted handle
169 */
170 private static MethodHandle adaptUpcallForIMR(MethodHandle target, boolean dropReturn) {
171 if (target.type().returnType() != MemorySegment.class)
172 throw new IllegalArgumentException("Must return MemorySegment for IMR");
173
174 target = collectArguments(MH_BUFFER_COPY, 1, target); // (MemorySegment, ...) MemorySegment
175
176 if (dropReturn) { // no handling for return value, need to drop it
177 target = dropReturn(target);
178 } else {
179 // adjust return type so it matches the inferred type of the effective
180 // function descriptor
181 target = target.asType(target.type().changeReturnType(MemorySegment.class));
182 }
183
184 return target;
185 }
186
187 public static UpcallStubFactory arrangeUpcallHelper(MethodType targetType, boolean isInMemoryReturn, boolean dropReturn,
188 ABIDescriptor abi, CallingSequence callingSequence) {
189 if (isInMemoryReturn) {
190 // simulate the adaptation to get the type
191 MethodHandle fakeTarget = MethodHandles.empty(targetType);
192 targetType = adaptUpcallForIMR(fakeTarget, dropReturn).type();
193 }
194
195 UpcallStubFactory factory = UpcallLinker.makeFactory(targetType, abi, callingSequence);
196
197 if (isInMemoryReturn) {
198 final UpcallStubFactory finalFactory = factory;
199 factory = (target, scope) -> {
200 target = adaptUpcallForIMR(target, dropReturn);
201 return finalFactory.makeStub(target, scope);
202 };
203 }
204
205 return factory;
206 }
207
208 private static MemorySegment bufferCopy(MemorySegment dest, MemorySegment buffer) {
209 return dest.copyFrom(buffer);
210 }
211
212 public static Class<?> primitiveCarrierForSize(long size, boolean useFloat) {
213 return primitiveLayoutForSize(size, useFloat).carrier();
214 }
215
216 public static ValueLayout primitiveLayoutForSize(long size, boolean useFloat) {
217 if (useFloat) {
218 if (size == 4) {
219 return JAVA_FLOAT;
220 } else if (size == 8) {
221 return JAVA_DOUBLE;
222 }
223 } else {
224 if (size == 1) {
225 return JAVA_BYTE;
226 } else if (size == 2) {
227 return JAVA_SHORT;
228 } else if (size <= 4) {
229 return JAVA_INT;
230 } else if (size <= 8) {
231 return JAVA_LONG;
232 }
233 }
234
235 throw new IllegalArgumentException("No layout for size: " + size + " isFloat=" + useFloat);
236 }
237
238 public static Linker getSystemLinker() {
239 return switch (CABI.current()) {
240 case WIN_64 -> Windowsx64Linker.getInstance();
241 case SYS_V -> SysVx64Linker.getInstance();
242 case LINUX_AARCH_64 -> LinuxAArch64Linker.getInstance();
243 case MAC_OS_AARCH_64 -> MacOsAArch64Linker.getInstance();
244 case WIN_AARCH_64 -> WindowsAArch64Linker.getInstance();
245 case LINUX_PPC_64 -> LinuxPPC64Linker.getInstance();
246 case LINUX_PPC_64_LE -> LinuxPPC64leLinker.getInstance();
247 case LINUX_RISCV_64 -> LinuxRISCV64Linker.getInstance();
248 case LINUX_S390 -> LinuxS390Linker.getInstance();
249 case FALLBACK -> FallbackLinker.getInstance();
250 case UNSUPPORTED -> throw new UnsupportedOperationException("Platform does not support native linker");
251 };
252 }
253
254 public static String toJavaStringInternal(MemorySegment segment, long start) {
255 int len = strlen(segment, start);
256 byte[] bytes = new byte[len];
257 MemorySegment.copy(segment, JAVA_BYTE, start, bytes, 0, len);
258 return new String(bytes, StandardCharsets.UTF_8);
259 }
260
261 private static int strlen(MemorySegment segment, long start) {
262 // iterate until overflow (String can only hold a byte[], whose length can be expressed as an int)
263 for (int offset = 0; offset >= 0; offset++) {
264 byte curr = segment.get(JAVA_BYTE, start + offset);
265 if (curr == 0) {
266 return offset;
267 }
268 }
269 throw new IllegalArgumentException("String too large");
270 }
271
272 static Map<VMStorage, Integer> indexMap(Binding.Move[] moves) {
273 return IntStream.range(0, moves.length)
274 .boxed()
275 .collect(Collectors.toMap(i -> moves[i].storage(), i -> i));
276 }
277
278 static MethodHandle mergeArguments(MethodHandle mh, int sourceIndex, int destIndex) {
279 MethodType oldType = mh.type();
280 Class<?> sourceType = oldType.parameterType(sourceIndex);
281 Class<?> destType = oldType.parameterType(destIndex);
282 if (sourceType != destType) {
283 // TODO meet?
284 throw new IllegalArgumentException("Parameter types differ: " + sourceType + " != " + destType);
285 }
286 MethodType newType = oldType.dropParameterTypes(destIndex, destIndex + 1);
287 int[] reorder = new int[oldType.parameterCount()];
288 if (destIndex < sourceIndex) {
289 sourceIndex--;
290 }
291 for (int i = 0, index = 0; i < reorder.length; i++) {
292 if (i != destIndex) {
293 reorder[i] = index++;
294 } else {
295 reorder[i] = sourceIndex;
296 }
297 }
298 return permuteArguments(mh, newType, reorder);
299 }
300
301
302 public static MethodHandle swapArguments(MethodHandle mh, int firstArg, int secondArg) {
303 MethodType mtype = mh.type();
304 int[] perms = new int[mtype.parameterCount()];
305 MethodType swappedType = MethodType.methodType(mtype.returnType());
306 for (int i = 0 ; i < perms.length ; i++) {
307 int dst = i;
308 if (i == firstArg) dst = secondArg;
309 if (i == secondArg) dst = firstArg;
310 perms[i] = dst;
311 swappedType = swappedType.appendParameterTypes(mtype.parameterType(dst));
312 }
313 return permuteArguments(mh, swappedType, perms);
314 }
315
316 private static MethodHandle reachabilityFenceHandle(Class<?> type) {
317 return MH_REACHABILITY_FENCE.asType(MethodType.methodType(void.class, type));
318 }
319
320 public static void handleUncaughtException(Throwable t) {
321 if (t != null) {
322 try {
323 t.printStackTrace();
324 System.err.println("Unrecoverable uncaught exception encountered. The VM will now exit");
325 } finally {
326 JLA.exit(1);
327 }
328 }
329 }
330
331 public static long unboxSegment(MemorySegment segment) {
332 if (!segment.isNative()) {
333 throw new IllegalArgumentException("Heap segment not allowed: " + segment);
334 }
335 return segment.address();
336 }
337
338 public static void checkExceptions(MethodHandle target) {
339 Class<?>[] exceptions = JLIA.exceptionTypes(target);
340 if (exceptions != null && exceptions.length != 0) {
341 throw new IllegalArgumentException("Target handle may throw exceptions: " + Arrays.toString(exceptions));
342 }
343 }
344
345 public static MethodHandle maybeInsertAllocator(FunctionDescriptor descriptor, MethodHandle handle) {
346 if (descriptor.returnLayout().isEmpty() || !(descriptor.returnLayout().get() instanceof GroupLayout)) {
347 // not returning segment, just insert a throwing allocator
348 handle = insertArguments(handle, 1, THROWING_ALLOCATOR);
349 }
350 return handle;
351 }
352
353 public static MethodHandle maybeCheckCaptureSegment(MethodHandle handle, LinkerOptions options) {
354 if (options.hasCapturedCallState()) {
355 // (<target address>, SegmentAllocator, <capture segment>, ...) -> ...
356 handle = MethodHandles.filterArguments(handle, 2, MH_CHECK_CAPTURE_SEGMENT);
357 }
358 return handle;
359 }
360
361 @ForceInline
362 public static MemorySegment checkCaptureSegment(MemorySegment captureSegment) {
363 Objects.requireNonNull(captureSegment);
364 if (captureSegment.equals(MemorySegment.NULL)) {
365 throw new IllegalArgumentException("Capture segment is NULL: " + captureSegment);
366 }
367 return captureSegment.asSlice(0, CapturableState.LAYOUT);
368 }
369
370 @ForceInline
371 public static void checkSymbol(MemorySegment symbol) {
372 Objects.requireNonNull(symbol);
373 if (symbol.equals(MemorySegment.NULL))
374 throw new IllegalArgumentException("Symbol is NULL: " + symbol);
375 }
376
377 static void checkType(Class<?> actualType, Class<?> expectedType) {
378 if (expectedType != actualType) {
379 throw new IllegalArgumentException(
380 String.format("Invalid operand type: %s. %s expected", actualType, expectedType));
381 }
382 }
383
384 public static boolean isPowerOfTwo(int width) {
385 return Integer.bitCount(width) == 1;
386 }
387
388 static long pickChunkOffset(long chunkOffset, long byteWidth, int chunkWidth) {
389 return ByteOrder.nativeOrder() == ByteOrder.BIG_ENDIAN
390 ? byteWidth - chunkWidth - chunkOffset
391 : chunkOffset;
392 }
393
394 public static Arena newBoundedArena(long size) {
395 return new Arena() {
396 final Arena arena = Arena.ofConfined();
397 final SegmentAllocator slicingAllocator = SegmentAllocator.slicingAllocator(arena.allocate(size));
398
399 @Override
400 public Scope scope() {
401 return arena.scope();
402 }
403
404 @Override
405 public void close() {
406 arena.close();
407 }
408
409 @Override
410 public MemorySegment allocate(long byteSize, long byteAlignment) {
411 return slicingAllocator.allocate(byteSize, byteAlignment);
412 }
413 };
414 }
415
416 public static Arena newEmptyArena() {
417 return new Arena() {
418 final Arena arena = Arena.ofConfined();
419
420 @Override
421 public Scope scope() {
422 return arena.scope();
423 }
424
425 @Override
426 public void close() {
427 arena.close();
428 }
429
430 @Override
431 public MemorySegment allocate(long byteSize, long byteAlignment) {
432 throw new UnsupportedOperationException();
433 }
434 };
435 }
436
437 public static final class SimpleVaArg {
438 public final MemoryLayout layout;
439 public final Object value;
440
441 public SimpleVaArg(MemoryLayout layout, Object value) {
442 this.layout = layout;
443 this.value = value;
444 }
445
446 public VarHandle varHandle() {
447 return layout.varHandle();
448 }
449 }
450
451 static void writeOverSized(MemorySegment ptr, Class<?> type, Object o) {
452 // use VH_LONG for integers to zero out the whole register in the process
453 if (type == long.class) {
454 ptr.set(JAVA_LONG_UNALIGNED, 0, (long) o);
455 } else if (type == int.class) {
456 ptr.set(JAVA_LONG_UNALIGNED, 0, (int) o);
457 } else if (type == short.class) {
458 ptr.set(JAVA_LONG_UNALIGNED, 0, (short) o);
459 } else if (type == char.class) {
460 ptr.set(JAVA_LONG_UNALIGNED, 0, (char) o);
461 } else if (type == byte.class) {
462 ptr.set(JAVA_LONG_UNALIGNED, 0, (byte) o);
463 } else if (type == float.class) {
464 ptr.set(JAVA_FLOAT_UNALIGNED, 0, (float) o);
465 } else if (type == double.class) {
466 ptr.set(JAVA_DOUBLE_UNALIGNED, 0, (double) o);
467 } else if (type == boolean.class) {
468 boolean b = (boolean)o;
469 ptr.set(JAVA_LONG_UNALIGNED, 0, b ? (long)1 : (long)0);
470 } else {
471 throw new IllegalArgumentException("Unsupported carrier: " + type);
472 }
473 }
474
475 static void write(MemorySegment ptr, long offset, Class<?> type, Object o) {
476 if (type == long.class) {
477 ptr.set(JAVA_LONG_UNALIGNED, offset, (long) o);
478 } else if (type == int.class) {
479 ptr.set(JAVA_INT_UNALIGNED, offset, (int) o);
480 } else if (type == short.class) {
481 ptr.set(JAVA_SHORT_UNALIGNED, offset, (short) o);
482 } else if (type == char.class) {
483 ptr.set(JAVA_CHAR_UNALIGNED, offset, (char) o);
484 } else if (type == byte.class) {
485 ptr.set(JAVA_BYTE, offset, (byte) o);
486 } else if (type == float.class) {
487 ptr.set(JAVA_FLOAT_UNALIGNED, offset, (float) o);
488 } else if (type == double.class) {
489 ptr.set(JAVA_DOUBLE_UNALIGNED, offset, (double) o);
490 } else if (type == boolean.class) {
491 ptr.set(JAVA_BOOLEAN, offset, (boolean) o);
492 } else {
493 throw new IllegalArgumentException("Unsupported carrier: " + type);
494 }
495 }
496
497 static Object read(MemorySegment ptr, long offset, Class<?> type) {
498 if (type == long.class) {
499 return ptr.get(JAVA_LONG_UNALIGNED, offset);
500 } else if (type == int.class) {
501 return ptr.get(JAVA_INT_UNALIGNED, offset);
502 } else if (type == short.class) {
503 return ptr.get(JAVA_SHORT_UNALIGNED, offset);
504 } else if (type == char.class) {
505 return ptr.get(JAVA_CHAR_UNALIGNED, offset);
506 } else if (type == byte.class) {
507 return ptr.get(JAVA_BYTE, offset);
508 } else if (type == float.class) {
509 return ptr.get(JAVA_FLOAT_UNALIGNED, offset);
510 } else if (type == double.class) {
511 return ptr.get(JAVA_DOUBLE_UNALIGNED, offset);
512 } else if (type == boolean.class) {
513 return ptr.get(JAVA_BOOLEAN, offset);
514 } else {
515 throw new IllegalArgumentException("Unsupported carrier: " + type);
516 }
517 }
518 }