1/*
2 * Copyright (c) 1997, 2018, 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.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#include "precompiled.hpp"
26#include "jvm.h"
27#include "asm/macroAssembler.hpp"
28#include "compiler/disassembler.hpp"
29#include "classfile/javaClasses.inline.hpp"
30#include "interpreter/interpreter.hpp"
31#include "interpreter/interpreterRuntime.hpp"
32#include "memory/allocation.inline.hpp"
33#include "memory/resourceArea.hpp"
34#include "prims/methodHandles.hpp"
35#include "runtime/flags/flagSetting.hpp"
36#include "runtime/frame.inline.hpp"
37#include "utilities/preserveException.hpp"
38
39#define __ Disassembler::hook<MacroAssembler>(__FILE__, __LINE__, _masm)->
40
41#ifdef PRODUCT
42#define BLOCK_COMMENT(str) /* nothing */
43#define STOP(error) stop(error)
44#else
45#define BLOCK_COMMENT(str) __ block_comment(str)
46#define STOP(error) block_comment(error); __ stop(error)
47#endif
48
49#define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
50
51void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) {
52 if (VerifyMethodHandles)
53 verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class),
54 "MH argument is a Class");
55 __ movptr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes()));
56}
57
58#ifdef ASSERT
59static int check_nonzero(const char* xname, int x) {
60 assert(x != 0, "%s should be nonzero", xname);
61 return x;
62}
63#define NONZERO(x) check_nonzero(#x, x)
64#else //ASSERT
65#define NONZERO(x) (x)
66#endif //ASSERT
67
68#ifdef ASSERT
69void MethodHandles::verify_klass(MacroAssembler* _masm,
70 Register obj, SystemDictionary::WKID klass_id,
71 const char* error_message) {
72 InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id);
73 Klass* klass = SystemDictionary::well_known_klass(klass_id);
74 Register temp = rdi;
75 Register temp2 = noreg;
76 LP64_ONLY(temp2 = rscratch1); // used by MacroAssembler::cmpptr
77 Label L_ok, L_bad;
78 BLOCK_COMMENT("verify_klass {");
79 __ verify_oop(obj);
80 __ testptr(obj, obj);
81 __ jcc(Assembler::zero, L_bad);
82 __ push(temp); if (temp2 != noreg) __ push(temp2);
83#define UNPUSH { if (temp2 != noreg) __ pop(temp2); __ pop(temp); }
84 __ load_klass(temp, obj);
85 __ cmpptr(temp, ExternalAddress((address) klass_addr));
86 __ jcc(Assembler::equal, L_ok);
87 intptr_t super_check_offset = klass->super_check_offset();
88 __ movptr(temp, Address(temp, super_check_offset));
89 __ cmpptr(temp, ExternalAddress((address) klass_addr));
90 __ jcc(Assembler::equal, L_ok);
91 UNPUSH;
92 __ bind(L_bad);
93 __ STOP(error_message);
94 __ BIND(L_ok);
95 UNPUSH;
96 BLOCK_COMMENT("} verify_klass");
97}
98
99void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {
100 Label L;
101 BLOCK_COMMENT("verify_ref_kind {");
102 __ movl(temp, Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes())));
103 __ shrl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT);
104 __ andl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK);
105 __ cmpl(temp, ref_kind);
106 __ jcc(Assembler::equal, L);
107 { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);
108 jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);
109 if (ref_kind == JVM_REF_invokeVirtual ||
110 ref_kind == JVM_REF_invokeSpecial)
111 // could do this for all ref_kinds, but would explode assembly code size
112 trace_method_handle(_masm, buf);
113 __ STOP(buf);
114 }
115 BLOCK_COMMENT("} verify_ref_kind");
116 __ bind(L);
117}
118
119#endif //ASSERT
120
121void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
122 bool for_compiler_entry) {
123 assert(method == rbx, "interpreter calling convention");
124
125 Label L_no_such_method;
126 __ testptr(rbx, rbx);
127 __ jcc(Assembler::zero, L_no_such_method);
128
129 __ verify_method_ptr(method);
130
131 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
132 Label run_compiled_code;
133 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
134 // compiled code in threads for which the event is enabled. Check here for
135 // interp_only_mode if these events CAN be enabled.
136#ifdef _LP64
137 Register rthread = r15_thread;
138#else
139 Register rthread = temp;
140 __ get_thread(rthread);
141#endif
142 // interp_only is an int, on little endian it is sufficient to test the byte only
143 // Is a cmpl faster?
144 __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0);
145 __ jccb(Assembler::zero, run_compiled_code);
146 __ jmp(Address(method, Method::interpreter_entry_offset()));
147 __ BIND(run_compiled_code);
148 }
149
150 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
151 Method::from_interpreted_offset();
152 __ jmp(Address(method, entry_offset));
153
154 __ bind(L_no_such_method);
155 __ jump(RuntimeAddress(StubRoutines::throw_AbstractMethodError_entry()));
156}
157
158void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
159 Register recv, Register method_temp,
160 Register temp2,
161 bool for_compiler_entry) {
162 BLOCK_COMMENT("jump_to_lambda_form {");
163 // This is the initial entry point of a lazy method handle.
164 // After type checking, it picks up the invoker from the LambdaForm.
165 assert_different_registers(recv, method_temp, temp2);
166 assert(recv != noreg, "required register");
167 assert(method_temp == rbx, "required register for loading method");
168
169 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); });
170
171 // Load the invoker, as MH -> MH.form -> LF.vmentry
172 __ verify_oop(recv);
173 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())), temp2);
174 __ verify_oop(method_temp);
175 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())), temp2);
176 __ verify_oop(method_temp);
177 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes())), temp2);
178 __ verify_oop(method_temp);
179 __ access_load_at(T_ADDRESS, IN_HEAP, method_temp,
180 Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes())),
181 noreg, noreg);
182
183 if (VerifyMethodHandles && !for_compiler_entry) {
184 // make sure recv is already on stack
185 __ movptr(temp2, Address(method_temp, Method::const_offset()));
186 __ load_sized_value(temp2,
187 Address(temp2, ConstMethod::size_of_parameters_offset()),
188 sizeof(u2), /*is_signed*/ false);
189 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
190 Label L;
191 __ cmpoop(recv, __ argument_address(temp2, -1));
192 __ jcc(Assembler::equal, L);
193 __ movptr(rax, __ argument_address(temp2, -1));
194 __ STOP("receiver not on stack");
195 __ BIND(L);
196 }
197
198 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
199 BLOCK_COMMENT("} jump_to_lambda_form");
200}
201
202
203// Code generation
204address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
205 vmIntrinsics::ID iid) {
206 const bool not_for_compiler_entry = false; // this is the interpreter entry
207 assert(is_signature_polymorphic(iid), "expected invoke iid");
208 if (iid == vmIntrinsics::_invokeGeneric ||
209 iid == vmIntrinsics::_compiledLambdaForm) {
210 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
211 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
212 // They all allow an appendix argument.
213 __ hlt(); // empty stubs make SG sick
214 return NULL;
215 }
216
217 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
218 // rbx: Method*
219 // rdx: argument locator (parameter slot count, added to rsp)
220 // rcx: used as temp to hold mh or receiver
221 // rax, rdi: garbage temps, blown away
222 Register rdx_argp = rdx; // argument list ptr, live on error paths
223 Register rax_temp = rax;
224 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled
225 Register rbx_method = rbx; // eventual target of this invocation
226
227 // here's where control starts out:
228 __ align(CodeEntryAlignment);
229 address entry_point = __ pc();
230
231 if (VerifyMethodHandles) {
232 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
233
234 Label L;
235 BLOCK_COMMENT("verify_intrinsic_id {");
236 __ cmpw(Address(rbx_method, Method::intrinsic_id_offset_in_bytes()), (int) iid);
237 __ jcc(Assembler::equal, L);
238 if (iid == vmIntrinsics::_linkToVirtual ||
239 iid == vmIntrinsics::_linkToSpecial) {
240 // could do this for all kinds, but would explode assembly code size
241 trace_method_handle(_masm, "bad Method*::intrinsic_id");
242 }
243 __ STOP("bad Method*::intrinsic_id");
244 __ bind(L);
245 BLOCK_COMMENT("} verify_intrinsic_id");
246 }
247
248 // First task: Find out how big the argument list is.
249 Address rdx_first_arg_addr;
250 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
251 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
252 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
253 __ movptr(rdx_argp, Address(rbx_method, Method::const_offset()));
254 __ load_sized_value(rdx_argp,
255 Address(rdx_argp, ConstMethod::size_of_parameters_offset()),
256 sizeof(u2), /*is_signed*/ false);
257 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
258 rdx_first_arg_addr = __ argument_address(rdx_argp, -1);
259 } else {
260 DEBUG_ONLY(rdx_argp = noreg);
261 }
262
263 if (!is_signature_polymorphic_static(iid)) {
264 __ movptr(rcx_mh, rdx_first_arg_addr);
265 DEBUG_ONLY(rdx_argp = noreg);
266 }
267
268 // rdx_first_arg_addr is live!
269
270 trace_method_handle_interpreter_entry(_masm, iid);
271
272 if (iid == vmIntrinsics::_invokeBasic) {
273 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);
274
275 } else {
276 // Adjust argument list by popping the trailing MemberName argument.
277 Register rcx_recv = noreg;
278 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
279 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
280 __ movptr(rcx_recv = rcx, rdx_first_arg_addr);
281 }
282 DEBUG_ONLY(rdx_argp = noreg);
283 Register rbx_member = rbx_method; // MemberName ptr; incoming method ptr is dead now
284 __ pop(rax_temp); // return address
285 __ pop(rbx_member); // extract last argument
286 __ push(rax_temp); // re-push return address
287 generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);
288 }
289
290 return entry_point;
291}
292
293void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
294 vmIntrinsics::ID iid,
295 Register receiver_reg,
296 Register member_reg,
297 bool for_compiler_entry) {
298 assert(is_signature_polymorphic(iid), "expected invoke iid");
299 Register rbx_method = rbx; // eventual target of this invocation
300 // temps used in this code are not used in *either* compiled or interpreted calling sequences
301#ifdef _LP64
302 Register temp1 = rscratch1;
303 Register temp2 = rscratch2;
304 Register temp3 = rax;
305 if (for_compiler_entry) {
306 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment");
307 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
308 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
309 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
310 }
311#else
312 Register temp1 = (for_compiler_entry ? rsi : rdx);
313 Register temp2 = rdi;
314 Register temp3 = rax;
315 if (for_compiler_entry) {
316 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : rcx), "only valid assignment");
317 assert_different_registers(temp1, rcx, rdx);
318 assert_different_registers(temp2, rcx, rdx);
319 assert_different_registers(temp3, rcx, rdx);
320 }
321#endif
322 else {
323 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP
324 }
325 assert_different_registers(temp1, temp2, temp3, receiver_reg);
326 assert_different_registers(temp1, temp2, temp3, member_reg);
327
328 if (iid == vmIntrinsics::_invokeBasic) {
329 // indirect through MH.form.vmentry.vmtarget
330 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry);
331
332 } else {
333 // The method is a member invoker used by direct method handles.
334 if (VerifyMethodHandles) {
335 // make sure the trailing argument really is a MemberName (caller responsibility)
336 verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_invoke_MemberName),
337 "MemberName required for invokeVirtual etc.");
338 }
339
340 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()));
341 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()));
342 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()));
343 Address vmtarget_method( rbx_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes()));
344
345 Register temp1_recv_klass = temp1;
346 if (iid != vmIntrinsics::_linkToStatic) {
347 __ verify_oop(receiver_reg);
348 if (iid == vmIntrinsics::_linkToSpecial) {
349 // Don't actually load the klass; just null-check the receiver.
350 __ null_check(receiver_reg);
351 } else {
352 // load receiver klass itself
353 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes());
354 __ load_klass(temp1_recv_klass, receiver_reg);
355 __ verify_klass_ptr(temp1_recv_klass);
356 }
357 BLOCK_COMMENT("check_receiver {");
358 // The receiver for the MemberName must be in receiver_reg.
359 // Check the receiver against the MemberName.clazz
360 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
361 // Did not load it above...
362 __ load_klass(temp1_recv_klass, receiver_reg);
363 __ verify_klass_ptr(temp1_recv_klass);
364 }
365 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
366 Label L_ok;
367 Register temp2_defc = temp2;
368 __ load_heap_oop(temp2_defc, member_clazz, temp3);
369 load_klass_from_Class(_masm, temp2_defc);
370 __ verify_klass_ptr(temp2_defc);
371 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
372 // If we get here, the type check failed!
373 __ STOP("receiver class disagrees with MemberName.clazz");
374 __ bind(L_ok);
375 }
376 BLOCK_COMMENT("} check_receiver");
377 }
378 if (iid == vmIntrinsics::_linkToSpecial ||
379 iid == vmIntrinsics::_linkToStatic) {
380 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
381 }
382
383 // Live registers at this point:
384 // member_reg - MemberName that was the trailing argument
385 // temp1_recv_klass - klass of stacked receiver, if needed
386 // rsi/r13 - interpreter linkage (if interpreted)
387 // rcx, rdx, rsi, rdi, r8 - compiler arguments (if compiled)
388
389 Label L_incompatible_class_change_error;
390 switch (iid) {
391 case vmIntrinsics::_linkToSpecial:
392 if (VerifyMethodHandles) {
393 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
394 }
395 __ load_heap_oop(rbx_method, member_vmtarget);
396 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
397 break;
398
399 case vmIntrinsics::_linkToStatic:
400 if (VerifyMethodHandles) {
401 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
402 }
403 __ load_heap_oop(rbx_method, member_vmtarget);
404 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
405 break;
406
407 case vmIntrinsics::_linkToVirtual:
408 {
409 // same as TemplateTable::invokevirtual,
410 // minus the CP setup and profiling:
411
412 if (VerifyMethodHandles) {
413 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
414 }
415
416 // pick out the vtable index from the MemberName, and then we can discard it:
417 Register temp2_index = temp2;
418 __ access_load_at(T_ADDRESS, IN_HEAP, temp2_index, member_vmindex, noreg, noreg);
419
420 if (VerifyMethodHandles) {
421 Label L_index_ok;
422 __ cmpl(temp2_index, 0);
423 __ jcc(Assembler::greaterEqual, L_index_ok);
424 __ STOP("no virtual index");
425 __ BIND(L_index_ok);
426 }
427
428 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
429 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
430
431 // get target Method* & entry point
432 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method);
433 break;
434 }
435
436 case vmIntrinsics::_linkToInterface:
437 {
438 // same as TemplateTable::invokeinterface
439 // (minus the CP setup and profiling, with different argument motion)
440 if (VerifyMethodHandles) {
441 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
442 }
443
444 Register temp3_intf = temp3;
445 __ load_heap_oop(temp3_intf, member_clazz);
446 load_klass_from_Class(_masm, temp3_intf);
447 __ verify_klass_ptr(temp3_intf);
448
449 Register rbx_index = rbx_method;
450 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_index, member_vmindex, noreg, noreg);
451 if (VerifyMethodHandles) {
452 Label L;
453 __ cmpl(rbx_index, 0);
454 __ jcc(Assembler::greaterEqual, L);
455 __ STOP("invalid vtable index for MH.invokeInterface");
456 __ bind(L);
457 }
458
459 // given intf, index, and recv klass, dispatch to the implementation method
460 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
461 // note: next two args must be the same:
462 rbx_index, rbx_method,
463 temp2,
464 L_incompatible_class_change_error);
465 break;
466 }
467
468 default:
469 fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid));
470 break;
471 }
472
473 // Live at this point:
474 // rbx_method
475 // rsi/r13 (if interpreted)
476
477 // After figuring out which concrete method to call, jump into it.
478 // Note that this works in the interpreter with no data motion.
479 // But the compiled version will require that rcx_recv be shifted out.
480 __ verify_method_ptr(rbx_method);
481 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry);
482
483 if (iid == vmIntrinsics::_linkToInterface) {
484 __ bind(L_incompatible_class_change_error);
485 __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
486 }
487 }
488}
489
490#ifndef PRODUCT
491void trace_method_handle_stub(const char* adaptername,
492 oop mh,
493 intptr_t* saved_regs,
494 intptr_t* entry_sp) {
495 // called as a leaf from native code: do not block the JVM!
496 bool has_mh = (strstr(adaptername, "/static") == NULL &&
497 strstr(adaptername, "linkTo") == NULL); // static linkers don't have MH
498 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx";
499 tty->print_cr("MH %s %s=" PTR_FORMAT " sp=" PTR_FORMAT,
500 adaptername, mh_reg_name,
501 p2i(mh), p2i(entry_sp));
502
503 if (Verbose) {
504 tty->print_cr("Registers:");
505 const int saved_regs_count = RegisterImpl::number_of_registers;
506 for (int i = 0; i < saved_regs_count; i++) {
507 Register r = as_Register(i);
508 // The registers are stored in reverse order on the stack (by pusha).
509 tty->print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
510 if ((i + 1) % 4 == 0) {
511 tty->cr();
512 } else {
513 tty->print(", ");
514 }
515 }
516 tty->cr();
517
518 {
519 // dumping last frame with frame::describe
520
521 JavaThread* p = JavaThread::active();
522
523 ResourceMark rm;
524 PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here
525 FrameValues values;
526
527 // Note: We want to allow trace_method_handle from any call site.
528 // While trace_method_handle creates a frame, it may be entered
529 // without a PC on the stack top (e.g. not just after a call).
530 // Walking that frame could lead to failures due to that invalid PC.
531 // => carefully detect that frame when doing the stack walking
532
533 // Current C frame
534 frame cur_frame = os::current_frame();
535
536 // Robust search of trace_calling_frame (independant of inlining).
537 // Assumes saved_regs comes from a pusha in the trace_calling_frame.
538 assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?");
539 frame trace_calling_frame = os::get_sender_for_C_frame(&cur_frame);
540 while (trace_calling_frame.fp() < saved_regs) {
541 trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame);
542 }
543
544 // safely create a frame and call frame::describe
545 intptr_t *dump_sp = trace_calling_frame.sender_sp();
546 intptr_t *dump_fp = trace_calling_frame.link();
547
548 bool walkable = has_mh; // whether the traced frame shoud be walkable
549
550 if (walkable) {
551 // The previous definition of walkable may have to be refined
552 // if new call sites cause the next frame constructor to start
553 // failing. Alternatively, frame constructors could be
554 // modified to support the current or future non walkable
555 // frames (but this is more intrusive and is not considered as
556 // part of this RFE, which will instead use a simpler output).
557 frame dump_frame = frame(dump_sp, dump_fp);
558 dump_frame.describe(values, 1);
559 } else {
560 // Stack may not be walkable (invalid PC above FP):
561 // Add descriptions without building a Java frame to avoid issues
562 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
563 values.describe(-1, dump_sp, "sp for #1");
564 }
565 values.describe(-1, entry_sp, "raw top of stack");
566
567 tty->print_cr("Stack layout:");
568 values.print(p);
569 }
570 if (has_mh && oopDesc::is_oop(mh)) {
571 mh->print();
572 if (java_lang_invoke_MethodHandle::is_instance(mh)) {
573 if (java_lang_invoke_MethodHandle::form_offset_in_bytes() != 0)
574 java_lang_invoke_MethodHandle::form(mh)->print();
575 }
576 }
577 }
578}
579
580// The stub wraps the arguments in a struct on the stack to avoid
581// dealing with the different calling conventions for passing 6
582// arguments.
583struct MethodHandleStubArguments {
584 const char* adaptername;
585 oopDesc* mh;
586 intptr_t* saved_regs;
587 intptr_t* entry_sp;
588};
589void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) {
590 trace_method_handle_stub(args->adaptername,
591 args->mh,
592 args->saved_regs,
593 args->entry_sp);
594}
595
596void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
597 if (!TraceMethodHandles) return;
598 BLOCK_COMMENT(err_msg("trace_method_handle %s {", adaptername));
599 __ enter();
600 __ andptr(rsp, -16); // align stack if needed for FPU state
601 __ pusha();
602 __ mov(rbx, rsp); // for retreiving saved_regs
603 // Note: saved_regs must be in the entered frame for the
604 // robust stack walking implemented in trace_method_handle_stub.
605
606 // save FP result, valid at some call sites (adapter_opt_return_float, ...)
607 __ increment(rsp, -2 * wordSize);
608 if (UseSSE >= 2) {
609 __ movdbl(Address(rsp, 0), xmm0);
610 } else if (UseSSE == 1) {
611 __ movflt(Address(rsp, 0), xmm0);
612 } else {
613 __ fst_d(Address(rsp, 0));
614 }
615
616 // Incoming state:
617 // rcx: method handle
618 //
619 // To avoid calling convention issues, build a record on the stack
620 // and pass the pointer to that instead.
621 __ push(rbp); // entry_sp (with extra align space)
622 __ push(rbx); // pusha saved_regs
623 __ push(rcx); // mh
624 __ push(rcx); // slot for adaptername
625 __ movptr(Address(rsp, 0), (intptr_t) adaptername);
626 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp);
627 __ increment(rsp, sizeof(MethodHandleStubArguments));
628
629 if (UseSSE >= 2) {
630 __ movdbl(xmm0, Address(rsp, 0));
631 } else if (UseSSE == 1) {
632 __ movflt(xmm0, Address(rsp, 0));
633 } else {
634 __ fld_d(Address(rsp, 0));
635 }
636 __ increment(rsp, 2 * wordSize);
637
638 __ popa();
639 __ leave();
640 BLOCK_COMMENT("} trace_method_handle");
641}
642#endif //PRODUCT
643