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