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