1 /*
2 * Copyright (c) 2016, 2021, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2016, 2017 SAP SE. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27 #include "jvm.h"
28 #include "asm/macroAssembler.inline.hpp"
29 #include "classfile/javaClasses.inline.hpp"
30 #include "classfile/vmClasses.hpp"
31 #include "interpreter/interpreter.hpp"
32 #include "logging/log.hpp"
33 #include "logging/logStream.hpp"
34 #include "memory/allocation.inline.hpp"
35 #include "memory/resourceArea.hpp"
36 #include "prims/jvmtiExport.hpp"
37 #include "prims/methodHandles.hpp"
38 #include "runtime/frame.inline.hpp"
39 #include "runtime/stubRoutines.hpp"
40 #include "utilities/preserveException.hpp"
41
42 #ifdef PRODUCT
43 #define __ _masm->
44 #define BLOCK_COMMENT(str) /* nothing */
45 #else
46 #define __ (Verbose ? (_masm->block_comment(FILE_AND_LINE),_masm):_masm)->
47 #define BLOCK_COMMENT(str) __ block_comment(str)
48 #endif
49
50 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
51
52 // Workaround for C++ overloading nastiness on '0' for RegisterOrConstant.
53 static RegisterOrConstant constant(int value) {
54 return RegisterOrConstant(value);
55 }
56
57 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg,
58 Register temp_reg, Register temp2_reg) {
59 if (VerifyMethodHandles) {
60 verify_klass(_masm, klass_reg, VM_CLASS_ID(java_lang_Class),
61 temp_reg, temp2_reg, "MH argument is a Class");
62 }
63 __ z_lg(klass_reg, Address(klass_reg, java_lang_Class::klass_offset()));
64 }
65
66
67 #ifdef ASSERT
68 static int check_nonzero(const char* xname, int x) {
69 assert(x != 0, "%s should be nonzero", xname);
70 return x;
71 }
72 #define NONZERO(x) check_nonzero(#x, x)
73 #else
74 #define NONZERO(x) (x)
75 #endif
76
77 #ifdef ASSERT
78 void MethodHandles::verify_klass(MacroAssembler* _masm,
79 Register obj_reg, vmClassID klass_id,
80 Register temp_reg, Register temp2_reg,
81 const char* error_message) {
82
83 InstanceKlass** klass_addr = vmClasses::klass_addr_at(klass_id);
84 Klass* klass = vmClasses::klass_at(klass_id);
85
86 assert(temp_reg != Z_R0 && // Is used as base register!
87 temp_reg != noreg && temp2_reg != noreg, "need valid registers!");
88
89 NearLabel L_ok, L_bad;
90
91 BLOCK_COMMENT("verify_klass {");
92
93 __ verify_oop(obj_reg, FILE_AND_LINE);
94 __ compareU64_and_branch(obj_reg, (intptr_t)0L, Assembler::bcondEqual, L_bad);
95 __ load_klass(temp_reg, obj_reg);
96 // klass_addr is a klass in allstatic SystemDictionaryHandles. Can't get GCed.
97 __ load_const_optimized(temp2_reg, (address)klass_addr);
98 __ z_lg(temp2_reg, Address(temp2_reg));
99 __ compareU64_and_branch(temp_reg, temp2_reg, Assembler::bcondEqual, L_ok);
100
101 intptr_t super_check_offset = klass->super_check_offset();
102 __ z_lg(temp_reg, Address(temp_reg, super_check_offset));
103 __ compareU64_and_branch(temp_reg, temp2_reg, Assembler::bcondEqual, L_ok);
104 __ BIND(L_bad);
105 __ stop(error_message);
106 __ BIND(L_ok);
107
108 BLOCK_COMMENT("} verify_klass");
109 }
110
111 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind,
112 Register member_reg, Register temp ) {
113 NearLabel L;
114 BLOCK_COMMENT("verify_ref_kind {");
115
116 __ z_llgf(temp,
117 Address(member_reg,
118 NONZERO(java_lang_invoke_MemberName::flags_offset())));
119 __ z_srl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT);
120 __ z_nilf(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK);
121 __ compare32_and_branch(temp, constant(ref_kind), Assembler::bcondEqual, L);
122
123 {
124 char *buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);
125
126 jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);
127 if (ref_kind == JVM_REF_invokeVirtual || ref_kind == JVM_REF_invokeSpecial) {
128 // Could do this for all ref_kinds, but would explode assembly code size.
129 trace_method_handle(_masm, buf);
130 }
131 __ stop(buf);
132 }
133
134 BLOCK_COMMENT("} verify_ref_kind");
135
136 __ bind(L);
137 }
138 #endif // ASSERT
139
140 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register target,
141 Register temp, bool for_compiler_entry) {
142 assert(method == Z_method, "interpreter calling convention");
143 __ verify_method_ptr(method);
144
145 assert(target != method, "don 't you kill the method reg!");
146
147 Label L_no_such_method;
148
149 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
150 // JVMTI events, such as single-stepping, are implemented partly
151 // by avoiding running compiled code in threads for which the
152 // event is enabled. Check here for interp_only_mode if these
153 // events CAN be enabled.
154 __ verify_thread();
155
156 Label run_compiled_code;
157
158 __ load_and_test_int(temp, Address(Z_thread, JavaThread::interp_only_mode_offset()));
159 __ z_bre(run_compiled_code);
160
161 // Null method test is replicated below in compiled case,
162 // it might be able to address across the verify_thread().
163 __ z_ltgr(temp, method);
164 __ z_bre(L_no_such_method);
165
166 __ z_lg(target, Address(method, Method::interpreter_entry_offset()));
167 __ z_br(target);
168
169 __ bind(run_compiled_code);
170 }
171
172 // Compiled case, either static or fall-through from runtime conditional.
173 __ z_ltgr(temp, method);
174 __ z_bre(L_no_such_method);
175
176 ByteSize offset = for_compiler_entry ?
177 Method::from_compiled_offset() : Method::from_interpreted_offset();
178 Address method_from(method, offset);
179
180 __ z_lg(target, method_from);
181 __ z_br(target);
182
183 __ bind(L_no_such_method);
184 assert(StubRoutines::throw_AbstractMethodError_entry() != NULL, "not yet generated!");
185 __ load_const_optimized(target, StubRoutines::throw_AbstractMethodError_entry());
186 __ z_br(target);
187 }
188
189 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
190 Register recv, Register method_temp,
191 Register temp2, Register temp3,
192 bool for_compiler_entry) {
193
194 // This is the initial entry point of a lazy method handle.
195 // After type checking, it picks up the invoker from the LambdaForm.
196 assert_different_registers(recv, method_temp, temp2, temp3);
197 assert(method_temp == Z_method, "required register for loading method");
198
199 BLOCK_COMMENT("jump_to_lambda_form {");
200
201 // Load the invoker, as MH -> MH.form -> LF.vmentry
202 __ verify_oop(recv, FILE_AND_LINE);
203 __ load_heap_oop(method_temp,
204 Address(recv,
205 NONZERO(java_lang_invoke_MethodHandle::form_offset())),
206 noreg, noreg, IS_NOT_NULL);
207 __ verify_oop(method_temp, FILE_AND_LINE);
208 __ load_heap_oop(method_temp,
209 Address(method_temp,
210 NONZERO(java_lang_invoke_LambdaForm::vmentry_offset())),
211 noreg, noreg, IS_NOT_NULL);
212 __ verify_oop(method_temp, FILE_AND_LINE);
213 __ load_heap_oop(method_temp,
214 Address(method_temp,
215 NONZERO(java_lang_invoke_MemberName::method_offset())),
216 noreg, noreg, IS_NOT_NULL);
217 __ verify_oop(method_temp, FILE_AND_LINE);
218 __ z_lg(method_temp,
219 Address(method_temp,
220 NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset())));
221
222 if (VerifyMethodHandles && !for_compiler_entry) {
223 // Make sure recv is already on stack.
224 NearLabel L;
225 Address paramSize(temp2, ConstMethod::size_of_parameters_offset());
226
227 __ z_lg(temp2, Address(method_temp, Method::const_offset()));
228 __ load_sized_value(temp2, paramSize, sizeof(u2), /*is_signed*/ false);
229 // if (temp2 != recv) stop
230 __ z_lg(temp2, __ argument_address(temp2, temp2, 0));
231 __ compare64_and_branch(temp2, recv, Assembler::bcondEqual, L);
232 __ stop("receiver not on stack");
233 __ BIND(L);
234 }
235
236 jump_from_method_handle(_masm, method_temp, temp2, Z_R0, for_compiler_entry);
237
238 BLOCK_COMMENT("} jump_to_lambda_form");
239 }
240
241 // code generation
242 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
243 vmIntrinsics::ID iid) {
244 const bool not_for_compiler_entry = false; // This is the interpreter entry.
245 assert(is_signature_polymorphic(iid), "expected invoke iid");
246
247 if (iid == vmIntrinsics::_invokeGeneric || iid == vmIntrinsics::_compiledLambdaForm) {
248 // Perhaps surprisingly, the symbolic references visible to Java
249 // are not directly used. They are linked to Java-generated
250 // adapters via MethodHandleNatives.linkMethod. They all allow an
251 // appendix argument.
252 __ should_not_reach_here(); // Empty stubs make SG sick.
253 return NULL;
254 }
255
256 // No need in interpreter entry for linkToNative for now.
257 // Interpreter calls compiled entry through i2c.
258 if (iid == vmIntrinsics::_linkToNative) {
259 __ should_not_reach_here(); // Empty stubs make SG sick.
260 return NULL;
261 }
262
263 // Z_R10: sender SP (must preserve; see prepare_to_jump_from_interprted)
264 // Z_method: method
265 // Z_ARG1 (Gargs): incoming argument list (must preserve)
266 Register Z_R4_param_size = Z_R4; // size of parameters
267 address code_start = __ pc();
268
269 // Here is where control starts out:
270 __ align(CodeEntryAlignment);
271
272 address entry_point = __ pc();
273
274 if (VerifyMethodHandles) {
275 Label L;
276 BLOCK_COMMENT("verify_intrinsic_id {");
277
278 // Supplement to 8139891: _intrinsic_id exceeded 1-byte size limit.
279 if (Method::intrinsic_id_size_in_bytes() == 1) {
280 __ z_cli(Address(Z_method, Method::intrinsic_id_offset_in_bytes()), (int)iid);
281 } else {
282 assert(Method::intrinsic_id_size_in_bytes() == 2, "size error: check Method::_intrinsic_id");
283 __ z_lh(Z_R0_scratch, Address(Z_method, Method::intrinsic_id_offset_in_bytes()));
284 __ z_chi(Z_R0_scratch, (int)iid);
285 }
286 __ z_bre(L);
287
288 if (iid == vmIntrinsics::_linkToVirtual || iid == vmIntrinsics::_linkToSpecial) {
289 // Could do this for all kinds, but would explode assembly code size.
290 trace_method_handle(_masm, "bad Method::intrinsic_id");
291 }
292
293 __ stop("bad Method::intrinsic_id");
294 __ bind(L);
295
296 BLOCK_COMMENT("} verify_intrinsic_id");
297 }
298
299 // First task: Find out how big the argument list is.
300 Address Z_R4_first_arg_addr;
301 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
302
303 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic,
304 "must be _invokeBasic or a linkTo intrinsic");
305
306 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
307 Address paramSize(Z_R1_scratch, ConstMethod::size_of_parameters_offset());
308
309 __ z_lg(Z_R1_scratch, Address(Z_method, Method::const_offset()));
310 __ load_sized_value(Z_R4_param_size, paramSize, sizeof(u2), /*is_signed*/ false);
311 Z_R4_first_arg_addr = __ argument_address(Z_R4_param_size, Z_R4_param_size, 0);
312 } else {
313 DEBUG_ONLY(Z_R4_param_size = noreg);
314 }
315
316 Register Z_mh = noreg;
317 if (!is_signature_polymorphic_static(iid)) {
318 Z_mh = Z_ARG4;
319 __ z_lg(Z_mh, Z_R4_first_arg_addr);
320 DEBUG_ONLY(Z_R4_param_size = noreg);
321 }
322
323 // Z_R4_first_arg_addr is live!
324
325 trace_method_handle_interpreter_entry(_masm, iid);
326
327 if (iid == vmIntrinsics::_invokeBasic) {
328 __ pc(); // just for the block comment
329 generate_method_handle_dispatch(_masm, iid, Z_mh, noreg, not_for_compiler_entry);
330 } else {
331 // Adjust argument list by popping the trailing MemberName argument.
332 Register Z_recv = noreg;
333
334 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
335 // Load the receiver (not the MH; the actual MemberName's receiver)
336 // up from the interpreter stack.
337 __ z_lg(Z_recv = Z_R5, Z_R4_first_arg_addr);
338 DEBUG_ONLY(Z_R4_param_size = noreg);
339 }
340
341 Register Z_member = Z_method; // MemberName ptr; incoming method ptr is dead now
342
343 __ z_lg(Z_member, __ argument_address(constant(1)));
344 __ add2reg(Z_esp, Interpreter::stackElementSize);
345 generate_method_handle_dispatch(_masm, iid, Z_recv, Z_member, not_for_compiler_entry);
346 }
347
348 return entry_point;
349 }
350
351 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
352 vmIntrinsics::ID iid,
353 Register receiver_reg,
354 Register member_reg,
355 bool for_compiler_entry) {
356 assert(is_signature_polymorphic(iid), "expected invoke iid");
357
358 Register temp1 = for_compiler_entry ? Z_R10 : Z_R6;
359 Register temp2 = Z_R12;
360 Register temp3 = Z_R11;
361 Register temp4 = Z_R13;
362
363 if (for_compiler_entry) {
364 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : Z_ARG1),
365 "only valid assignment");
366 }
367 if (receiver_reg != noreg) {
368 assert_different_registers(temp1, temp2, temp3, temp4, receiver_reg);
369 }
370 if (member_reg != noreg) {
371 assert_different_registers(temp1, temp2, temp3, temp4, member_reg);
372 }
373 if (!for_compiler_entry) { // Don't trash last SP.
374 assert_different_registers(temp1, temp2, temp3, temp4, Z_R10);
375 }
376
377 if (iid == vmIntrinsics::_invokeBasic || iid == vmIntrinsics::_linkToNative) {
378 if (iid == vmIntrinsics::_linkToNative) {
379 assert(for_compiler_entry, "only compiler entry is supported");
380 }
381 __ pc(); // Just for the block comment.
382 // Indirect through MH.form.vmentry.vmtarget.
383 jump_to_lambda_form(_masm, receiver_reg, Z_method, Z_R1, temp3, for_compiler_entry);
384 return;
385 }
386
387 // The method is a member invoker used by direct method handles.
388 if (VerifyMethodHandles) {
389 // Make sure the trailing argument really is a MemberName (caller responsibility).
390 verify_klass(_masm, member_reg,
391 VM_CLASS_ID(MemberName_klass),
392 temp1, temp2,
393 "MemberName required for invokeVirtual etc.");
394 }
395
396 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset()));
397 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset()));
398 Address member_vmtarget(member_reg, NONZERO(java_lang_invoke_MemberName::method_offset()));
399 Address vmtarget_method(Z_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset()));
400 Register temp1_recv_klass = temp1;
401
402 if (iid != vmIntrinsics::_linkToStatic) {
403 __ verify_oop(receiver_reg, FILE_AND_LINE);
404 if (iid == vmIntrinsics::_linkToSpecial) {
405 // Don't actually load the klass; just null-check the receiver.
406 __ null_check(receiver_reg);
407 } else {
408 // Load receiver klass itself.
409 __ null_check(receiver_reg, Z_R0, oopDesc::klass_offset_in_bytes());
410 __ load_klass(temp1_recv_klass, receiver_reg);
411 __ verify_klass_ptr(temp1_recv_klass);
412 }
413 BLOCK_COMMENT("check_receiver {");
414 // The receiver for the MemberName must be in receiver_reg.
415 // Check the receiver against the MemberName.clazz.
416 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
417 // Did not load it above...
418 __ load_klass(temp1_recv_klass, receiver_reg);
419 __ verify_klass_ptr(temp1_recv_klass);
420 }
421
422 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
423 NearLabel L_ok;
424 Register temp2_defc = temp2;
425
426 __ load_heap_oop(temp2_defc, member_clazz,
427 noreg, noreg, IS_NOT_NULL);
428 load_klass_from_Class(_masm, temp2_defc, temp3, temp4);
429 __ verify_klass_ptr(temp2_defc);
430 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, temp4, L_ok);
431 // If we get here, the type check failed!
432 __ stop("receiver class disagrees with MemberName.clazz");
433 __ bind(L_ok);
434 }
435 BLOCK_COMMENT("} check_receiver");
436 }
437 if (iid == vmIntrinsics::_linkToSpecial || iid == vmIntrinsics::_linkToStatic) {
438 DEBUG_ONLY(temp1_recv_klass = noreg); // These guys didn't load the recv_klass.
439 }
440
441 // Live registers at this point:
442 // member_reg - MemberName that was the trailing argument.
443 // temp1_recv_klass - Klass of stacked receiver, if needed.
444 // Z_R10 - Interpreter linkage if interpreted.
445
446 bool method_is_live = false;
447
448 switch (iid) {
449 case vmIntrinsics::_linkToSpecial:
450 if (VerifyMethodHandles) {
451 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
452 }
453 __ load_heap_oop(Z_method, member_vmtarget,
454 noreg, noreg, IS_NOT_NULL);
455 __ z_lg(Z_method, vmtarget_method);
456 method_is_live = true;
457 break;
458
459 case vmIntrinsics::_linkToStatic:
460 if (VerifyMethodHandles) {
461 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
462 }
463 __ load_heap_oop(Z_method, member_vmtarget,
464 noreg, noreg, IS_NOT_NULL);
465 __ z_lg(Z_method, vmtarget_method);
466 method_is_live = true;
467 break;
468
469 case vmIntrinsics::_linkToVirtual: {
470 // Same as TemplateTable::invokevirtual, minus the CP setup and profiling.
471 if (VerifyMethodHandles) {
472 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
473 }
474
475 // Pick out the vtable index from the MemberName, and then we can discard it.
476 Register temp2_index = temp2;
477 __ z_lg(temp2_index, member_vmindex);
478
479 if (VerifyMethodHandles) {
480 // if (member_vmindex < 0) stop
481 NearLabel L_index_ok;
482 __ compare32_and_branch(temp2_index, constant(0), Assembler::bcondNotLow, L_index_ok);
483 __ stop("no virtual index");
484 __ BIND(L_index_ok);
485 }
486
487 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
488 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
489
490 // Get target method and entry point.
491 __ lookup_virtual_method(temp1_recv_klass, temp2_index, Z_method);
492 method_is_live = true;
493 break;
494 }
495
496 case vmIntrinsics::_linkToInterface: {
497 // Same as TemplateTable::invokeinterface, minus the CP setup
498 // and profiling, with different argument motion.
499 if (VerifyMethodHandles) {
500 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
501 }
502
503 Register temp3_intf = temp3;
504
505 __ load_heap_oop(temp3_intf, member_clazz,
506 noreg, noreg, IS_NOT_NULL);
507 load_klass_from_Class(_masm, temp3_intf, temp2, temp4);
508
509 Register Z_index = Z_method;
510
511 __ z_lg(Z_index, member_vmindex);
512
513 if (VerifyMethodHandles) {
514 NearLabel L;
515 // if (member_vmindex < 0) stop
516 __ compare32_and_branch(Z_index, constant(0), Assembler::bcondNotLow, L);
517 __ stop("invalid vtable index for MH.invokeInterface");
518 __ bind(L);
519 }
520
521 // Given interface, index, and recv klass, dispatch to the implementation method.
522 Label L_no_such_interface;
523 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
524 // Note: next two args must be the same:
525 Z_index, Z_method, temp2,
526 L_no_such_interface);
527 jump_from_method_handle(_masm, Z_method, temp2, Z_R0, for_compiler_entry);
528
529 __ bind(L_no_such_interface);
530
531 // Throw exception.
532 __ load_const_optimized(Z_R1, StubRoutines::throw_IncompatibleClassChangeError_entry());
533 __ z_br(Z_R1);
534 break;
535 }
536
537 default:
538 fatal("unexpected intrinsic %d: %s", vmIntrinsics::as_int(iid), vmIntrinsics::name_at(iid));
539 break;
540 }
541
542 if (method_is_live) {
543 // Live at this point: Z_method, O5_savedSP (if interpreted).
544
545 // After figuring out which concrete method to call, jump into it.
546 // Note that this works in the interpreter with no data motion.
547 // But the compiled version will require that rcx_recv be shifted out.
548 jump_from_method_handle(_masm, Z_method, temp1, Z_R0, for_compiler_entry);
549 }
550 }
551
552 #ifndef PRODUCT
553 void trace_method_handle_stub(const char* adaptername,
554 oopDesc* mh,
555 intptr_t* sender_sp,
556 intptr_t* args,
557 intptr_t* tracing_fp) {
558 bool has_mh = (strstr(adaptername, "/static") == NULL &&
559 strstr(adaptername, "linkTo") == NULL); // Static linkers don't have MH.
560 const char* mh_reg_name = has_mh ? "Z_R4_mh" : "Z_R4";
561 log_info(methodhandles)("MH %s %s=" INTPTR_FORMAT " sender_sp=" INTPTR_FORMAT " args=" INTPTR_FORMAT,
562 adaptername, mh_reg_name,
563 p2i(mh), p2i(sender_sp), p2i(args));
564
565 LogTarget(Trace, methodhandles) lt;
566 if (lt.is_enabled()) {
567 // Dumping last frame with frame::describe.
568 ResourceMark rm;
569 LogStream ls(lt);
570 JavaThread* p = JavaThread::active();
571
572 // may not be needed by safer and unexpensive here
573 PreserveExceptionMark pem(Thread::current());
574 FrameValues values;
575
576 // Note: We want to allow trace_method_handle from any call site.
577 // While trace_method_handle creates a frame, it may be entered
578 // without a valid return PC in Z_R14 (e.g. not just after a call).
579 // Walking that frame could lead to failures due to that invalid PC.
580 // => carefully detect that frame when doing the stack walking.
581
582 // Walk up to the right frame using the "tracing_fp" argument.
583 frame cur_frame = os::current_frame(); // Current C frame.
584
585 while (cur_frame.fp() != tracing_fp) {
586 cur_frame = os::get_sender_for_C_frame(&cur_frame);
587 }
588
589 // Safely create a frame and call frame::describe.
590 intptr_t *dump_sp = cur_frame.sender_sp();
591 intptr_t *dump_fp = cur_frame.link();
592
593 bool walkable = has_mh; // Whether the traced frame shoud be walkable.
594
595 // The sender for cur_frame is the caller of trace_method_handle.
596 if (walkable) {
597 // The previous definition of walkable may have to be refined
598 // if new call sites cause the next frame constructor to start
599 // failing. Alternatively, frame constructors could be
600 // modified to support the current or future non walkable
601 // frames (but this is more intrusive and is not considered as
602 // part of this RFE, which will instead use a simpler output).
603 frame dump_frame = frame(dump_sp);
604 dump_frame.describe(values, 1);
605 } else {
606 // Robust dump for frames which cannot be constructed from sp/younger_sp
607 // Add descriptions without building a Java frame to avoid issues.
608 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
609 values.describe(-1, dump_sp, "sp");
610 }
611
612 bool has_args = has_mh; // Whether Z_esp is meaningful.
613
614 // Mark args, if seems valid (may not be valid for some adapters).
615 if (has_args) {
616 if ((args >= dump_sp) && (args < dump_fp)) {
617 values.describe(-1, args, "*Z_esp");
618 }
619 }
620
621 // Note: the unextended_sp may not be correct.
622 ls.print_cr(" stack layout:");
623 values.print_on(p, &ls);
624 if (has_mh && oopDesc::is_oop(mh)) {
625 mh->print_on(&ls);
626 if (java_lang_invoke_MethodHandle::is_instance(mh)) {
627 java_lang_invoke_MethodHandle::form(mh)->print_on(&ls);
628 }
629 }
630 }
631 }
632
633 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
634 if (!log_is_enabled(Info, methodhandles)) { return; }
635
636 // If arg registers are contiguous, we can use STMG/LMG.
637 assert((Z_ARG5->encoding() - Z_ARG1->encoding() + 1) == RegisterImpl::number_of_arg_registers, "Oops");
638
639 BLOCK_COMMENT("trace_method_handle {");
640
641 // Save argument registers (they are used in raise exception stub).
642 // Argument registers have contiguous register numbers -> we can use stmg/lmg.
643 __ z_stmg(Z_ARG1, Z_ARG5, 16, Z_SP);
644
645 // Setup arguments.
646 __ z_lgr(Z_ARG2, Z_ARG4); // mh, see generate_method_handle_interpreter_entry()
647 __ z_lgr(Z_ARG3, Z_R10); // sender_sp
648 __ z_lgr(Z_ARG4, Z_esp);
649 __ load_const_optimized(Z_ARG1, (void *)adaptername);
650 __ z_lgr(Z_ARG5, Z_SP); // tracing_fp
651 __ save_return_pc(); // saves Z_R14
652 __ push_frame_abi160(0);
653 __ call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub));
654 __ pop_frame();
655 __ restore_return_pc(); // restores to Z_R14
656
657 // Restore argument registers
658 __ z_lmg(Z_ARG1, Z_ARG5, 16, Z_SP);
659 __ zap_from_to(Z_SP, Z_SP, Z_R0, Z_R1, 50, -1);
660 __ zap_from_to(Z_SP, Z_SP, Z_R0, Z_R1, -1, 5);
661
662 BLOCK_COMMENT("} trace_method_handle");
663 }
664 #endif // !PRODUCT