1 /*
2 * Copyright (c) 2008, 2020, 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.inline.hpp"
28 #include "classfile/javaClasses.inline.hpp"
29 #include "interpreter/interpreter.hpp"
30 #include "interpreter/interp_masm.hpp"
31 #include "logging/log.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 __ _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
51 // Workaround for C++ overloading nastiness on '0' for RegisterOrConstant.
52 static RegisterOrConstant constant(int value) {
53 return RegisterOrConstant(value);
54 }
55
56 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg, Register temp_reg, Register temp2_reg) {
57 if (VerifyMethodHandles)
58 verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class), temp_reg, temp2_reg,
59 "MH argument is a Class");
60 __ ld_ptr(Address(klass_reg, java_lang_Class::klass_offset_in_bytes()), klass_reg);
61 }
62
63 #ifdef ASSERT
64 static int check_nonzero(const char* xname, int x) {
65 assert(x != 0, "%s should be nonzero", xname);
66 return x;
67 }
68 #define NONZERO(x) check_nonzero(#x, x)
69 #else //ASSERT
70 #define NONZERO(x) (x)
71 #endif //ASSERT
72
73 #ifdef ASSERT
74 void MethodHandles::verify_klass(MacroAssembler* _masm,
75 Register obj_reg, SystemDictionary::WKID klass_id,
76 Register temp_reg, Register temp2_reg,
77 const char* error_message) {
78 InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id);
79 Klass* klass = SystemDictionary::well_known_klass(klass_id);
80 bool did_save = false;
81 if (temp_reg == noreg || temp2_reg == noreg) {
82 temp_reg = L1;
83 temp2_reg = L2;
84 __ save_frame_and_mov(0, obj_reg, L0);
85 obj_reg = L0;
86 did_save = true;
87 }
88 Label L_ok, L_bad;
89 BLOCK_COMMENT("verify_klass {");
90 __ verify_oop(obj_reg);
91 __ br_null_short(obj_reg, Assembler::pn, L_bad);
92 __ load_klass(obj_reg, temp_reg);
93 __ set(ExternalAddress((Metadata**)klass_addr), temp2_reg);
94 __ ld_ptr(Address(temp2_reg, 0), temp2_reg);
95 __ cmp_and_brx_short(temp_reg, temp2_reg, Assembler::equal, Assembler::pt, L_ok);
96 intptr_t super_check_offset = klass->super_check_offset();
97 __ ld_ptr(Address(temp_reg, super_check_offset), temp_reg);
98 __ set(ExternalAddress((Metadata**)klass_addr), temp2_reg);
99 __ ld_ptr(Address(temp2_reg, 0), temp2_reg);
100 __ cmp_and_brx_short(temp_reg, temp2_reg, Assembler::equal, Assembler::pt, L_ok);
101 __ BIND(L_bad);
102 if (did_save) __ restore();
103 __ STOP(error_message);
104 __ BIND(L_ok);
105 if (did_save) __ restore();
106 BLOCK_COMMENT("} verify_klass");
107 }
108
109 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {
110 Label L;
111 BLOCK_COMMENT("verify_ref_kind {");
112 __ lduw(Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes())), temp);
113 __ srl( temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT, temp);
114 __ and3(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK, temp);
115 __ cmp_and_br_short(temp, ref_kind, Assembler::equal, Assembler::pt, L);
116 { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);
117 jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);
118 if (ref_kind == JVM_REF_invokeVirtual ||
119 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 __ STOP(buf);
123 }
124 BLOCK_COMMENT("} verify_ref_kind");
125 __ bind(L);
126 }
127
128 #endif // ASSERT
129
130 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register target, Register temp,
131 bool for_compiler_entry) {
132 Label L_no_such_method;
133 assert(method == G5_method, "interpreter calling convention");
134 assert_different_registers(method, target, temp);
135
136 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
137 Label run_compiled_code;
138 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
139 // compiled code in threads for which the event is enabled. Check here for
140 // interp_only_mode if these events CAN be enabled.
141 __ verify_thread();
142 const Address interp_only(G2_thread, JavaThread::interp_only_mode_offset());
143 __ ld(interp_only, temp);
144 __ cmp_and_br_short(temp, 0, Assembler::zero, Assembler::pt, run_compiled_code);
145 // Null method test is replicated below in compiled case,
146 // it might be able to address across the verify_thread()
147 __ br_null_short(G5_method, Assembler::pn, L_no_such_method);
148 __ ld_ptr(G5_method, in_bytes(Method::interpreter_entry_offset()), target);
149 __ jmp(target, 0);
150 __ delayed()->nop();
151 __ BIND(run_compiled_code);
152 // Note: we could fill some delay slots here, but
153 // it doesn't matter, since this is interpreter code.
154 }
155
156 // Compiled case, either static or fall-through from runtime conditional
157 __ br_null_short(G5_method, Assembler::pn, L_no_such_method);
158
159 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
160 Method::from_interpreted_offset();
161 __ ld_ptr(G5_method, in_bytes(entry_offset), target);
162 __ jmp(target, 0);
163 __ delayed()->nop();
164
165 __ bind(L_no_such_method);
166 AddressLiteral ame(StubRoutines::throw_AbstractMethodError_entry());
167 __ jump_to(ame, temp);
168 __ delayed()->nop();
169 }
170
171 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
172 Register recv, Register method_temp,
173 Register temp2, Register temp3,
174 bool for_compiler_entry) {
175 BLOCK_COMMENT("jump_to_lambda_form {");
176 // This is the initial entry point of a lazy method handle.
177 // After type checking, it picks up the invoker from the LambdaForm.
178 assert_different_registers(recv, method_temp, temp2); // temp3 is only passed on
179 assert(method_temp == G5_method, "required register for loading method");
180
181 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); });
182
183 // Load the invoker, as MH -> MH.form -> LF.vmentry
184 __ verify_oop(recv);
185 __ load_heap_oop(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes()), method_temp, temp2);
186 __ verify_oop(method_temp);
187 __ load_heap_oop(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes()), method_temp, temp2);
188 __ verify_oop(method_temp);
189 __ load_heap_oop(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()), method_temp, temp2);
190 __ verify_oop(method_temp);
191 __ ld_ptr(Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes())), method_temp);
192
193 if (VerifyMethodHandles && !for_compiler_entry) {
194 // make sure recv is already on stack
195 __ ld_ptr(method_temp, in_bytes(Method::const_offset()), temp2);
196 __ load_sized_value(Address(temp2, ConstMethod::size_of_parameters_offset()),
197 temp2,
198 sizeof(u2), /*is_signed*/ false);
199 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
200 Label L;
201 __ ld_ptr(__ argument_address(temp2, temp2, -1), temp2);
202 __ cmp_and_br_short(temp2, recv, Assembler::equal, Assembler::pt, L);
203 __ STOP("receiver not on stack");
204 __ BIND(L);
205 }
206
207 jump_from_method_handle(_masm, method_temp, temp2, temp3, for_compiler_entry);
208 BLOCK_COMMENT("} jump_to_lambda_form");
209 }
210
211
212 // Code generation
213 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
214 vmIntrinsics::ID iid) {
215 const bool not_for_compiler_entry = false; // this is the interpreter entry
216 assert(is_signature_polymorphic(iid), "expected invoke iid");
217 if (iid == vmIntrinsics::_invokeGeneric ||
218 iid == vmIntrinsics::_compiledLambdaForm) {
219 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
220 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
221 // They all allow an appendix argument.
222 __ should_not_reach_here(); // empty stubs make SG sick
223 return NULL;
224 }
225
226 // I5_savedSP/O5_savedSP: sender SP (must preserve; see prepare_to_jump_from_interpreted)
227 // G5_method: Method*
228 // G4 (Gargs): incoming argument list (must preserve)
229 // O0: used as temp to hold mh or receiver
230 // O1, O4: garbage temps, blown away
231 Register O1_scratch = O1;
232 Register O4_param_size = O4; // size of parameters
233
234 // here's where control starts out:
235 __ align(CodeEntryAlignment);
236 address entry_point = __ pc();
237
238 if (VerifyMethodHandles) {
239 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
240
241 Label L;
242 BLOCK_COMMENT("verify_intrinsic_id {");
243 __ lduh(Address(G5_method, Method::intrinsic_id_offset_in_bytes()), O1_scratch);
244 __ cmp_and_br_short(O1_scratch, (int) iid, Assembler::equal, Assembler::pt, L);
245 if (iid == vmIntrinsics::_linkToVirtual ||
246 iid == vmIntrinsics::_linkToSpecial) {
247 // could do this for all kinds, but would explode assembly code size
248 trace_method_handle(_masm, "bad Method*::intrinsic_id");
249 }
250 __ STOP("bad Method*::intrinsic_id");
251 __ bind(L);
252 BLOCK_COMMENT("} verify_intrinsic_id");
253 }
254
255 // First task: Find out how big the argument list is.
256 Address O4_first_arg_addr;
257 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
258 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
259 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
260 __ ld_ptr(G5_method, in_bytes(Method::const_offset()), O4_param_size);
261 __ load_sized_value(Address(O4_param_size, ConstMethod::size_of_parameters_offset()),
262 O4_param_size,
263 sizeof(u2), /*is_signed*/ false);
264 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
265 O4_first_arg_addr = __ argument_address(O4_param_size, O4_param_size, -1);
266 } else {
267 DEBUG_ONLY(O4_param_size = noreg);
268 }
269
270 Register O0_mh = noreg;
271 if (!is_signature_polymorphic_static(iid)) {
272 __ ld_ptr(O4_first_arg_addr, O0_mh = O0);
273 DEBUG_ONLY(O4_param_size = noreg);
274 }
275
276 // O4_first_arg_addr is live!
277
278 if (log_is_enabled(Info, methodhandles)) {
279 if (O0_mh != noreg)
280 __ mov(O0_mh, G3_method_handle); // make stub happy
281 trace_method_handle_interpreter_entry(_masm, iid);
282 }
283
284 if (iid == vmIntrinsics::_invokeBasic) {
285 generate_method_handle_dispatch(_masm, iid, O0_mh, noreg, not_for_compiler_entry);
286
287 } else {
288 // Adjust argument list by popping the trailing MemberName argument.
289 Register O0_recv = noreg;
290 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
291 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
292 __ ld_ptr(O4_first_arg_addr, O0_recv = O0);
293 DEBUG_ONLY(O4_param_size = noreg);
294 }
295 Register G5_member = G5_method; // MemberName ptr; incoming method ptr is dead now
296 __ ld_ptr(__ argument_address(constant(0)), G5_member);
297 __ add(Gargs, Interpreter::stackElementSize, Gargs);
298 generate_method_handle_dispatch(_masm, iid, O0_recv, G5_member, not_for_compiler_entry);
299 }
300
301 return entry_point;
302 }
303
304 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
305 vmIntrinsics::ID iid,
306 Register receiver_reg,
307 Register member_reg,
308 bool for_compiler_entry) {
309 assert(is_signature_polymorphic(iid), "expected invoke iid");
310 Register temp1 = (for_compiler_entry ? G1_scratch : O1);
311 Register temp2 = (for_compiler_entry ? G3_scratch : O2);
312 Register temp3 = (for_compiler_entry ? G4_scratch : O3);
313 Register temp4 = (for_compiler_entry ? noreg : O4);
314 if (for_compiler_entry) {
315 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : O0), "only valid assignment");
316 assert_different_registers(temp1, O0, O1, O2, O3, O4, O5);
317 assert_different_registers(temp2, O0, O1, O2, O3, O4, O5);
318 assert_different_registers(temp3, O0, O1, O2, O3, O4, O5);
319 assert_different_registers(temp4, O0, O1, O2, O3, O4, O5);
320 } else {
321 assert_different_registers(temp1, temp2, temp3, temp4, O5_savedSP); // don't trash lastSP
322 }
323 if (receiver_reg != noreg) assert_different_registers(temp1, temp2, temp3, temp4, receiver_reg);
324 if (member_reg != noreg) assert_different_registers(temp1, temp2, temp3, temp4, member_reg);
325
326 if (iid == vmIntrinsics::_invokeBasic) {
327 // indirect through MH.form.vmentry.vmtarget
328 jump_to_lambda_form(_masm, receiver_reg, G5_method, temp1, temp2, for_compiler_entry);
329
330 } else {
331 // The method is a member invoker used by direct method handles.
332 if (VerifyMethodHandles) {
333 // make sure the trailing argument really is a MemberName (caller responsibility)
334 verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(MemberName_klass),
335 temp1, temp2,
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( G5_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(receiver_reg, temp1_recv_klass);
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(receiver_reg, temp1_recv_klass);
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(member_clazz, temp2_defc, temp3);
368 load_klass_from_Class(_masm, temp2_defc, temp3, temp4);
369 __ verify_klass_ptr(temp2_defc);
370 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, temp4, 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 // O5_savedSP - interpreter linkage (if interpreted)
386 // O0..O5 - 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, temp2);
393 }
394 __ load_heap_oop(member_vmtarget, G5_method, temp3);
395 __ ld_ptr(vmtarget_method, G5_method);
396 break;
397
398 case vmIntrinsics::_linkToStatic:
399 if (VerifyMethodHandles) {
400 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp2);
401 }
402 __ load_heap_oop(member_vmtarget, G5_method, temp3);
403 __ ld_ptr(vmtarget_method, G5_method);
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, temp2);
413 }
414
415 // pick out the vtable index from the MemberName, and then we can discard it:
416 Register temp2_index = temp2;
417 __ ld_ptr(member_vmindex, temp2_index);
418
419 if (VerifyMethodHandles) {
420 Label L_index_ok;
421 __ cmp_and_br_short(temp2_index, (int) 0, Assembler::greaterEqual, Assembler::pn, L_index_ok);
422 __ STOP("no virtual index");
423 __ BIND(L_index_ok);
424 }
425
426 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
427 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
428
429 // get target Method* & entry point
430 __ lookup_virtual_method(temp1_recv_klass, temp2_index, G5_method);
431 break;
432 }
433
434 case vmIntrinsics::_linkToInterface:
435 {
436 // same as TemplateTable::invokeinterface
437 // (minus the CP setup and profiling, with different argument motion)
438 if (VerifyMethodHandles) {
439 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp2);
440 }
441
442 Register temp2_intf = temp2;
443 __ load_heap_oop(member_clazz, temp2_intf, temp3);
444 load_klass_from_Class(_masm, temp2_intf, temp3, temp4);
445 __ verify_klass_ptr(temp2_intf);
446
447 Register G5_index = G5_method;
448 __ ld_ptr(member_vmindex, G5_index);
449 if (VerifyMethodHandles) {
450 Label L;
451 __ cmp_and_br_short(G5_index, 0, Assembler::greaterEqual, Assembler::pt, L);
452 __ STOP("invalid vtable index for MH.invokeInterface");
453 __ bind(L);
454 }
455
456 // given intf, index, and recv klass, dispatch to the implementation method
457 __ lookup_interface_method(temp1_recv_klass, temp2_intf,
458 // note: next two args must be the same:
459 G5_index, G5_method,
460 temp3, temp4,
461 L_incompatible_class_change_error);
462 break;
463 }
464
465 default:
466 fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid));
467 break;
468 }
469
470 // Live at this point:
471 // G5_method
472 // O5_savedSP (if interpreted)
473
474 // After figuring out which concrete method to call, jump into it.
475 // Note that this works in the interpreter with no data motion.
476 // But the compiled version will require that rcx_recv be shifted out.
477 __ verify_method_ptr(G5_method);
478 jump_from_method_handle(_masm, G5_method, temp1, temp2, for_compiler_entry);
479
480 if (iid == vmIntrinsics::_linkToInterface) {
481 __ BIND(L_incompatible_class_change_error);
482 AddressLiteral icce(StubRoutines::throw_IncompatibleClassChangeError_entry());
483 __ jump_to(icce, temp1);
484 __ delayed()->nop();
485 }
486 }
487 }
488
489 #ifndef PRODUCT
490 void trace_method_handle_stub(const char* adaptername,
491 oopDesc* mh,
492 intptr_t* saved_sp,
493 intptr_t* args,
494 intptr_t* tracing_fp) {
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 ? "G3_mh" : "G3";
498 tty->print_cr("MH %s %s=" INTPTR_FORMAT " saved_sp=" INTPTR_FORMAT " args=" INTPTR_FORMAT,
499 adaptername, mh_reg_name,
500 p2i(mh), p2i(saved_sp), p2i(args));
501
502 if (Verbose) {
503 // dumping last frame with frame::describe
504
505 JavaThread* p = JavaThread::active();
506
507 ResourceMark rm;
508 PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here
509 FrameValues values;
510
511 // Note: We want to allow trace_method_handle from any call site.
512 // While trace_method_handle creates a frame, it may be entered
513 // without a valid return PC in O7 (e.g. not just after a call).
514 // Walking that frame could lead to failures due to that invalid PC.
515 // => carefully detect that frame when doing the stack walking
516
517 // walk up to the right frame using the "tracing_fp" argument
518 intptr_t* cur_sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
519 frame cur_frame(cur_sp, frame::unpatchable, NULL);
520
521 while (cur_frame.fp() != (intptr_t *)(STACK_BIAS+(uintptr_t)tracing_fp)) {
522 cur_frame = os::get_sender_for_C_frame(&cur_frame);
523 }
524
525 // safely create a frame and call frame::describe
526 intptr_t *dump_sp = cur_frame.sender_sp();
527 intptr_t *dump_fp = cur_frame.link();
528
529 bool walkable = has_mh; // whether the traced frame shoud be walkable
530
531 // the sender for cur_frame is the caller of trace_method_handle
532 if (walkable) {
533 // The previous definition of walkable may have to be refined
534 // if new call sites cause the next frame constructor to start
535 // failing. Alternatively, frame constructors could be
536 // modified to support the current or future non walkable
537 // frames (but this is more intrusive and is not considered as
538 // part of this RFE, which will instead use a simpler output).
539 frame dump_frame = frame(dump_sp,
540 cur_frame.sp(), // younger_sp
541 false); // no adaptation
542 dump_frame.describe(values, 1);
543 } else {
544 // Robust dump for frames which cannot be constructed from sp/younger_sp
545 // Add descriptions without building a Java frame to avoid issues
546 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
547 values.describe(-1, dump_sp, "sp");
548 }
549
550 bool has_args = has_mh; // whether Gargs is meaningful
551
552 // mark args, if seems valid (may not be valid for some adapters)
553 if (has_args) {
554 if ((args >= dump_sp) && (args < dump_fp)) {
555 values.describe(-1, args, "*G4_args");
556 }
557 }
558
559 // mark saved_sp, if seems valid (may not be valid for some adapters)
560 intptr_t *unbiased_sp = (intptr_t *)(STACK_BIAS+(uintptr_t)saved_sp);
561 const int ARG_LIMIT = 255, SLOP = 45, UNREASONABLE_STACK_MOVE = (ARG_LIMIT + SLOP);
562 if ((unbiased_sp >= dump_sp - UNREASONABLE_STACK_MOVE) && (unbiased_sp < dump_fp)) {
563 values.describe(-1, unbiased_sp, "*saved_sp+STACK_BIAS");
564 }
565
566 // Note: the unextended_sp may not be correct
567 tty->print_cr(" stack layout:");
568 values.print(p);
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 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
580 if (!log_is_enabled(Info, methodhandles)) return;
581 BLOCK_COMMENT("trace_method_handle {");
582 // save: Gargs, O5_savedSP
583 __ save_frame(16); // need space for saving required FPU state
584
585 __ set((intptr_t) adaptername, O0);
586 __ mov(G3_method_handle, O1);
587 __ mov(I5_savedSP, O2);
588 __ mov(Gargs, O3);
589 __ mov(I6, O4); // frame identifier for safe stack walking
590
591 // Save scratched registers that might be needed. Robustness is more
592 // important than optimizing the saves for this debug only code.
593
594 // save FP result, valid at some call sites (adapter_opt_return_float, ...)
595 Address d_save(FP, -sizeof(jdouble) + STACK_BIAS);
596 __ stf(FloatRegisterImpl::D, Ftos_d, d_save);
597 // Safely save all globals but G2 (handled by call_VM_leaf) and G7
598 // (OS reserved).
599 __ mov(G3_method_handle, L3);
600 __ mov(Gargs, L4);
601 __ mov(G5_method_type, L5);
602 __ mov(G6, L6);
603 __ mov(G1, L1);
604
605 __ call_VM_leaf(L2 /* for G2 */, CAST_FROM_FN_PTR(address, trace_method_handle_stub));
606
607 __ mov(L3, G3_method_handle);
608 __ mov(L4, Gargs);
609 __ mov(L5, G5_method_type);
610 __ mov(L6, G6);
611 __ mov(L1, G1);
612 __ ldf(FloatRegisterImpl::D, d_save, Ftos_d);
613
614 __ restore();
615 BLOCK_COMMENT("} trace_method_handle");
616 }
617 #endif // PRODUCT