1 /*
2 * Copyright (c) 1997, 2025, 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 "asm/macroAssembler.hpp"
26 #include "classfile/vmClasses.hpp"
27 #include "compiler/disassembler.hpp"
28 #include "classfile/javaClasses.inline.hpp"
29 #include "interpreter/interpreter.hpp"
30 #include "interpreter/interpreterRuntime.hpp"
31 #include "jvm.h"
32 #include "logging/log.hpp"
33 #include "logging/logStream.hpp"
34 #include "memory/allocation.inline.hpp"
35 #include "memory/resourceArea.hpp"
36 #include "prims/jvmtiExport.hpp"
37 #include "prims/methodHandles.hpp"
38 #include "runtime/flags/flagSetting.hpp"
39 #include "runtime/frame.inline.hpp"
40 #include "runtime/stubRoutines.hpp"
41 #include "utilities/formatBuffer.hpp"
42 #include "utilities/preserveException.hpp"
43
44 #define __ Disassembler::hook<MacroAssembler>(__FILE__, __LINE__, _masm)->
45
46 #ifdef PRODUCT
47 #define BLOCK_COMMENT(str) /* nothing */
48 #define STOP(error) stop(error)
49 #else
50 #define BLOCK_COMMENT(str) __ block_comment(str)
51 #define STOP(error) block_comment(error); __ stop(error)
52 #endif
53
54 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
55
56 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) {
57 if (VerifyMethodHandles)
58 verify_klass(_masm, klass_reg, VM_CLASS_ID(java_lang_Class),
59 "MH argument is a Class");
60 __ movptr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset()));
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, vmClassID klass_id,
76 const char* error_message) {
77 InstanceKlass** klass_addr = vmClasses::klass_addr_at(klass_id);
78 Klass* klass = vmClasses::klass_at(klass_id);
79 Register temp = rdi;
80 Label L_ok, L_bad;
81 BLOCK_COMMENT("verify_klass {");
82 __ verify_oop(obj);
83 __ testptr(obj, obj);
84 __ jcc(Assembler::zero, L_bad);
85 #define PUSH { __ push(temp); LP64_ONLY( __ push(rscratch1); ) }
86 #define POP { LP64_ONLY( __ pop(rscratch1); ) __ pop(temp); }
87 PUSH;
88 __ load_klass(temp, obj, rscratch1);
89 __ cmpptr(temp, ExternalAddress((address) klass_addr), rscratch1);
90 __ jcc(Assembler::equal, L_ok);
91 intptr_t super_check_offset = klass->super_check_offset();
92 __ movptr(temp, Address(temp, super_check_offset));
93 __ cmpptr(temp, ExternalAddress((address) klass_addr), rscratch1);
94 __ jcc(Assembler::equal, L_ok);
95 POP;
96 __ bind(L_bad);
97 __ STOP(error_message);
98 __ BIND(L_ok);
99 POP;
100 BLOCK_COMMENT("} verify_klass");
101 #undef POP
102 #undef PUSH
103 }
104
105 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {
106 Label L;
107 BLOCK_COMMENT("verify_ref_kind {");
108 __ movl(temp, Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset())));
109 __ shrl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT);
110 __ andl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK);
111 __ cmpl(temp, ref_kind);
112 __ jcc(Assembler::equal, L);
113 { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);
114 jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);
115 if (ref_kind == JVM_REF_invokeVirtual ||
116 ref_kind == JVM_REF_invokeSpecial)
117 // could do this for all ref_kinds, but would explode assembly code size
118 trace_method_handle(_masm, buf);
119 __ STOP(buf);
120 }
121 BLOCK_COMMENT("} verify_ref_kind");
122 __ bind(L);
123 }
124
125 #endif //ASSERT
126
127 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
128 bool for_compiler_entry) {
129 assert(method == rbx, "interpreter calling convention");
130
131 Label L_no_such_method;
132 __ testptr(rbx, rbx);
133 __ jcc(Assembler::zero, L_no_such_method);
134
135 __ verify_method_ptr(method);
136
137 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
138 Label run_compiled_code;
139 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
140 // compiled code in threads for which the event is enabled. Check here for
141 // interp_only_mode if these events CAN be enabled.
142 #ifdef _LP64
143 Register rthread = r15_thread;
144 #else
145 Register rthread = temp;
146 __ get_thread(rthread);
147 #endif
148 // interp_only is an int, on little endian it is sufficient to test the byte only
149 // Is a cmpl faster?
150 __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0);
151 __ jccb(Assembler::zero, run_compiled_code);
152 __ jmp(Address(method, Method::interpreter_entry_offset()));
153 __ BIND(run_compiled_code);
154 }
155
156 // The following jump might pass an inline type argument that was erased to Object as oop to a
157 // callee that expects inline type arguments to be passed as fields. We need to call the compiled
158 // value entry (_code->inline_entry_point() or _adapter->c2i_inline_entry()) which will take care
159 // of translating between the calling conventions.
160 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_inline_offset() :
161 Method::from_interpreted_offset();
162 __ jmp(Address(method, entry_offset));
163
164 __ bind(L_no_such_method);
165 __ jump(RuntimeAddress(SharedRuntime::throw_AbstractMethodError_entry()));
166 }
167
168 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
169 Register recv, Register method_temp,
170 Register temp2,
171 bool for_compiler_entry) {
172 BLOCK_COMMENT("jump_to_lambda_form {");
173 // This is the initial entry point of a lazy method handle.
174 // After type checking, it picks up the invoker from the LambdaForm.
175 assert_different_registers(recv, method_temp, temp2);
176 assert(recv != noreg, "required register");
177 assert(method_temp == rbx, "required register for loading method");
178
179 // Load the invoker, as MH -> MH.form -> LF.vmentry
180 __ verify_oop(recv);
181 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset())), temp2);
182 __ verify_oop(method_temp);
183 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset())), temp2);
184 __ verify_oop(method_temp);
185 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset())), temp2);
186 __ verify_oop(method_temp);
187 __ access_load_at(T_ADDRESS, IN_HEAP, method_temp,
188 Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset())),
189 noreg, noreg);
190
191 if (VerifyMethodHandles && !for_compiler_entry) {
192 // make sure recv is already on stack
193 __ movptr(temp2, Address(method_temp, Method::const_offset()));
194 __ load_sized_value(temp2,
195 Address(temp2, ConstMethod::size_of_parameters_offset()),
196 sizeof(u2), /*is_signed*/ false);
197 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
198 Label L;
199 __ cmpoop(recv, __ argument_address(temp2, -1));
200 __ jcc(Assembler::equal, L);
201 __ movptr(rax, __ argument_address(temp2, -1));
202 __ STOP("receiver not on stack");
203 __ BIND(L);
204 }
205
206 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
207 BLOCK_COMMENT("} jump_to_lambda_form");
208 }
209
210 void MethodHandles::jump_to_native_invoker(MacroAssembler* _masm, Register nep_reg, Register temp_target) {
211 BLOCK_COMMENT("jump_to_native_invoker {");
212 assert_different_registers(nep_reg, temp_target);
213 assert(nep_reg != noreg, "required register");
214
215 // Load the invoker, as NEP -> .invoker
216 __ verify_oop(nep_reg);
217 __ access_load_at(T_ADDRESS, IN_HEAP, temp_target,
218 Address(nep_reg, NONZERO(jdk_internal_foreign_abi_NativeEntryPoint::downcall_stub_address_offset_in_bytes())),
219 noreg, noreg);
220
221 __ jmp(temp_target);
222 BLOCK_COMMENT("} jump_to_native_invoker");
223 }
224
225
226 // Code generation
227 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
228 vmIntrinsics::ID iid) {
229 const bool not_for_compiler_entry = false; // this is the interpreter entry
230 assert(is_signature_polymorphic(iid), "expected invoke iid");
231 if (iid == vmIntrinsics::_invokeGeneric ||
232 iid == vmIntrinsics::_compiledLambdaForm) {
233 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
234 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
235 // They all allow an appendix argument.
236 __ hlt(); // empty stubs make SG sick
237 return nullptr;
238 }
239
240 // No need in interpreter entry for linkToNative for now.
241 // Interpreter calls compiled entry through i2c.
242 if (iid == vmIntrinsics::_linkToNative) {
243 __ hlt();
244 return nullptr;
245 }
246
247 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
248 // rbx: Method*
249 // rdx: argument locator (parameter slot count, added to rsp)
250 // rcx: used as temp to hold mh or receiver
251 // rax, rdi: garbage temps, blown away
252 Register rdx_argp = rdx; // argument list ptr, live on error paths
253 Register rax_temp = rax;
254 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled
255 Register rbx_method = rbx; // eventual target of this invocation
256
257 // here's where control starts out:
258 __ align(CodeEntryAlignment);
259 address entry_point = __ pc();
260
261 if (VerifyMethodHandles) {
262 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
263
264 Label L;
265 BLOCK_COMMENT("verify_intrinsic_id {");
266 __ cmpw(Address(rbx_method, Method::intrinsic_id_offset()), (int) iid);
267 __ jcc(Assembler::equal, L);
268 if (iid == vmIntrinsics::_linkToVirtual ||
269 iid == vmIntrinsics::_linkToSpecial) {
270 // could do this for all kinds, but would explode assembly code size
271 trace_method_handle(_masm, "bad Method*::intrinsic_id");
272 }
273 __ STOP("bad Method*::intrinsic_id");
274 __ bind(L);
275 BLOCK_COMMENT("} verify_intrinsic_id");
276 }
277
278 // First task: Find out how big the argument list is.
279 Address rdx_first_arg_addr;
280 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
281 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
282 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
283 __ movptr(rdx_argp, Address(rbx_method, Method::const_offset()));
284 __ load_sized_value(rdx_argp,
285 Address(rdx_argp, ConstMethod::size_of_parameters_offset()),
286 sizeof(u2), /*is_signed*/ false);
287 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
288 rdx_first_arg_addr = __ argument_address(rdx_argp, -1);
289 } else {
290 DEBUG_ONLY(rdx_argp = noreg);
291 }
292
293 if (!is_signature_polymorphic_static(iid)) {
294 __ movptr(rcx_mh, rdx_first_arg_addr);
295 DEBUG_ONLY(rdx_argp = noreg);
296 }
297
298 // rdx_first_arg_addr is live!
299
300 trace_method_handle_interpreter_entry(_masm, iid);
301
302 if (iid == vmIntrinsics::_invokeBasic) {
303 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);
304
305 } else {
306 // Adjust argument list by popping the trailing MemberName argument.
307 Register rcx_recv = noreg;
308 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
309 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
310 __ movptr(rcx_recv = rcx, rdx_first_arg_addr);
311 }
312 DEBUG_ONLY(rdx_argp = noreg);
313 Register rbx_member = rbx_method; // MemberName ptr; incoming method ptr is dead now
314 __ pop(rax_temp); // return address
315 __ pop(rbx_member); // extract last argument
316 __ push(rax_temp); // re-push return address
317 generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);
318 }
319
320 return entry_point;
321 }
322
323 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
324 vmIntrinsics::ID iid,
325 Register receiver_reg,
326 Register member_reg,
327 bool for_compiler_entry) {
328 assert(is_signature_polymorphic(iid), "expected invoke iid");
329 Register rbx_method = rbx; // eventual target of this invocation
330 // temps used in this code are not used in *either* compiled or interpreted calling sequences
331 #ifdef _LP64
332 Register temp1 = rscratch1;
333 Register temp2 = rscratch2;
334 Register temp3 = rax;
335 if (for_compiler_entry) {
336 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic || iid == vmIntrinsics::_linkToNative ? noreg : j_rarg0), "only valid assignment");
337 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
338 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
339 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
340 }
341 #else
342 Register temp1 = (for_compiler_entry ? rsi : rdx);
343 Register temp2 = rdi;
344 Register temp3 = rax;
345 if (for_compiler_entry) {
346 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic || iid == vmIntrinsics::_linkToNative ? noreg : rcx), "only valid assignment");
347 assert_different_registers(temp1, rcx, rdx);
348 assert_different_registers(temp2, rcx, rdx);
349 assert_different_registers(temp3, rcx, rdx);
350 }
351 #endif
352 else {
353 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP
354 }
355 assert_different_registers(temp1, temp2, temp3, receiver_reg);
356 assert_different_registers(temp1, temp2, temp3, member_reg);
357
358 if (iid == vmIntrinsics::_invokeBasic) {
359 // indirect through MH.form.vmentry.vmtarget
360 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry);
361 } else if (iid == vmIntrinsics::_linkToNative) {
362 assert(for_compiler_entry, "only compiler entry is supported");
363 jump_to_native_invoker(_masm, member_reg, temp1);
364 } else {
365 // The method is a member invoker used by direct method handles.
366 if (VerifyMethodHandles) {
367 // make sure the trailing argument really is a MemberName (caller responsibility)
368 verify_klass(_masm, member_reg, VM_CLASS_ID(java_lang_invoke_MemberName),
369 "MemberName required for invokeVirtual etc.");
370 }
371
372 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset()));
373 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset()));
374 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset()));
375 Address vmtarget_method( rbx_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset()));
376
377 Register temp1_recv_klass = temp1;
378 if (iid != vmIntrinsics::_linkToStatic) {
379 __ verify_oop(receiver_reg);
380 if (iid == vmIntrinsics::_linkToSpecial) {
381 // Don't actually load the klass; just null-check the receiver.
382 __ null_check(receiver_reg);
383 } else {
384 // load receiver klass itself
385 __ load_klass(temp1_recv_klass, receiver_reg, temp2);
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, temp2);
394 __ verify_klass_ptr(temp1_recv_klass);
395 }
396 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
397 Label L_ok;
398 Register temp2_defc = temp2;
399 __ load_heap_oop(temp2_defc, member_clazz, temp3);
400 load_klass_from_Class(_masm, temp2_defc);
401 __ verify_klass_ptr(temp2_defc);
402 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
403 // If we get here, the type check failed!
404 __ STOP("receiver class disagrees with MemberName.clazz");
405 __ bind(L_ok);
406 }
407 BLOCK_COMMENT("} check_receiver");
408 }
409 if (iid == vmIntrinsics::_linkToSpecial ||
410 iid == vmIntrinsics::_linkToStatic) {
411 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
412 }
413
414 // Live registers at this point:
415 // member_reg - MemberName that was the trailing argument
416 // temp1_recv_klass - klass of stacked receiver, if needed
417 // rsi/r13 - interpreter linkage (if interpreted)
418 // rcx, rdx, rsi, rdi, r8 - compiler arguments (if compiled)
419
420 Label L_incompatible_class_change_error;
421 switch (iid) {
422 case vmIntrinsics::_linkToSpecial:
423 if (VerifyMethodHandles) {
424 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
425 }
426 __ load_heap_oop(rbx_method, member_vmtarget);
427 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
428 break;
429
430 case vmIntrinsics::_linkToStatic:
431 if (VerifyMethodHandles) {
432 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
433 }
434 __ load_heap_oop(rbx_method, member_vmtarget);
435 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
436 break;
437
438 case vmIntrinsics::_linkToVirtual:
439 {
440 // same as TemplateTable::invokevirtual,
441 // minus the CP setup and profiling:
442
443 if (VerifyMethodHandles) {
444 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
445 }
446
447 // pick out the vtable index from the MemberName, and then we can discard it:
448 Register temp2_index = temp2;
449 __ access_load_at(T_ADDRESS, IN_HEAP, temp2_index, member_vmindex, noreg, noreg);
450
451 if (VerifyMethodHandles) {
452 Label L_index_ok;
453 __ cmpl(temp2_index, 0);
454 __ jcc(Assembler::greaterEqual, L_index_ok);
455 __ STOP("no virtual index");
456 __ BIND(L_index_ok);
457 }
458
459 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
460 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
461
462 // get target Method* & entry point
463 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method);
464 break;
465 }
466
467 case vmIntrinsics::_linkToInterface:
468 {
469 // same as TemplateTable::invokeinterface
470 // (minus the CP setup and profiling, with different argument motion)
471 if (VerifyMethodHandles) {
472 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
473 }
474
475 Register temp3_intf = temp3;
476 __ load_heap_oop(temp3_intf, member_clazz);
477 load_klass_from_Class(_masm, temp3_intf);
478 __ verify_klass_ptr(temp3_intf);
479
480 Register rbx_index = rbx_method;
481 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_index, member_vmindex, noreg, noreg);
482 if (VerifyMethodHandles) {
483 Label L;
484 __ cmpl(rbx_index, 0);
485 __ jcc(Assembler::greaterEqual, L);
486 __ STOP("invalid vtable index for MH.invokeInterface");
487 __ bind(L);
488 }
489
490 // given intf, index, and recv klass, dispatch to the implementation method
491 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
492 // note: next two args must be the same:
493 rbx_index, rbx_method,
494 temp2,
495 L_incompatible_class_change_error);
496 break;
497 }
498
499 default:
500 fatal("unexpected intrinsic %d: %s", vmIntrinsics::as_int(iid), vmIntrinsics::name_at(iid));
501 break;
502 }
503
504 // Live at this point:
505 // rbx_method
506 // rsi/r13 (if interpreted)
507
508 // After figuring out which concrete method to call, jump into it.
509 // Note that this works in the interpreter with no data motion.
510 // But the compiled version will require that rcx_recv be shifted out.
511 __ verify_method_ptr(rbx_method);
512 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry);
513
514 if (iid == vmIntrinsics::_linkToInterface) {
515 __ bind(L_incompatible_class_change_error);
516 __ jump(RuntimeAddress(SharedRuntime::throw_IncompatibleClassChangeError_entry()));
517 }
518 }
519 }
520
521 #ifndef PRODUCT
522 void trace_method_handle_stub(const char* adaptername,
523 oopDesc* mh,
524 intptr_t* saved_regs,
525 intptr_t* entry_sp) {
526 // called as a leaf from native code: do not block the JVM!
527 bool has_mh = (strstr(adaptername, "/static") == nullptr &&
528 strstr(adaptername, "linkTo") == nullptr); // static linkers don't have MH
529 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx";
530 log_info(methodhandles)("MH %s %s=" PTR_FORMAT " sp=" PTR_FORMAT, adaptername, mh_reg_name, p2i(mh), p2i(entry_sp));
531
532 LogTarget(Trace, methodhandles) lt;
533 if (lt.is_enabled()) {
534 ResourceMark rm;
535 LogStream ls(lt);
536 ls.print_cr("Registers:");
537 const int saved_regs_count = Register::number_of_registers;
538 for (int i = 0; i < saved_regs_count; i++) {
539 Register r = as_Register(i);
540 // The registers are stored in reverse order on the stack (by pusha).
541 #ifdef AMD64
542 int num_regs = UseAPX ? 32 : 16;
543 assert(Register::available_gp_registers() == num_regs, "sanity");
544 if (r == rsp) {
545 // rsp is actually not stored by pusha(), compute the old rsp from saved_regs (rsp after pusha): saved_regs + 16 = old rsp
546 ls.print("%3s=" PTR_FORMAT, r->name(), (intptr_t)(&saved_regs[num_regs]));
547 } else {
548 ls.print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
549 }
550 #else
551 ls.print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
552 #endif
553 if ((i + 1) % 4 == 0) {
554 ls.cr();
555 } else {
556 ls.print(", ");
557 }
558 }
559 ls.cr();
560
561 // Note: We want to allow trace_method_handle from any call site.
562 // While trace_method_handle creates a frame, it may be entered
563 // without a PC on the stack top (e.g. not just after a call).
564 // Walking that frame could lead to failures due to that invalid PC.
565 // => carefully detect that frame when doing the stack walking
566
567 {
568 // dumping last frame with frame::describe
569
570 JavaThread* p = JavaThread::active();
571
572 // may not be needed by safer and unexpensive here
573 PreserveExceptionMark pem(Thread::current());
574 FrameValues values;
575
576 frame cur_frame = os::current_frame();
577
578 if (cur_frame.fp() != nullptr) { // not walkable
579
580 // Robust search of trace_calling_frame (independent of inlining).
581 // Assumes saved_regs comes from a pusha in the trace_calling_frame.
582 //
583 // We have to start the search from cur_frame, because trace_calling_frame may be it.
584 // It is guaranteed that trace_calling_frame is different from the top frame.
585 // But os::current_frame() does NOT return the top frame: it returns the next frame under it (caller's frame).
586 // (Due to inlining and tail call optimizations, caller's frame doesn't necessarily correspond to the immediate
587 // caller in the source code.)
588 assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?");
589 frame trace_calling_frame = cur_frame;
590 while (trace_calling_frame.fp() < saved_regs) {
591 assert(trace_calling_frame.cb() == nullptr, "not a C frame");
592 trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame);
593 }
594 assert(trace_calling_frame.sp() < saved_regs, "wrong frame");
595
596 // safely create a frame and call frame::describe
597 intptr_t *dump_sp = trace_calling_frame.sender_sp();
598 intptr_t *dump_fp = trace_calling_frame.link();
599
600 if (has_mh) {
601 // The previous definition of walkable may have to be refined
602 // if new call sites cause the next frame constructor to start
603 // failing. Alternatively, frame constructors could be
604 // modified to support the current or future non walkable
605 // frames (but this is more intrusive and is not considered as
606 // part of this RFE, which will instead use a simpler output).
607 frame dump_frame = frame(dump_sp, dump_fp);
608 dump_frame.describe(values, 1);
609 } else {
610 // Stack may not be walkable (invalid PC above FP):
611 // Add descriptions without building a Java frame to avoid issues
612 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
613 values.describe(-1, dump_sp, "sp for #1");
614 }
615 }
616 values.describe(-1, entry_sp, "raw top of stack");
617
618 ls.print_cr("Stack layout:");
619 values.print_on(p, &ls);
620 }
621 if (has_mh && oopDesc::is_oop(mh)) {
622 mh->print_on(&ls);
623 if (java_lang_invoke_MethodHandle::is_instance(mh)) {
624 java_lang_invoke_MethodHandle::form(mh)->print_on(&ls);
625 }
626 }
627 }
628 }
629
630 // The stub wraps the arguments in a struct on the stack to avoid
631 // dealing with the different calling conventions for passing 6
632 // arguments.
633 struct MethodHandleStubArguments {
634 const char* adaptername;
635 oopDesc* mh;
636 intptr_t* saved_regs;
637 intptr_t* entry_sp;
638 };
639 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) {
640 trace_method_handle_stub(args->adaptername,
641 args->mh,
642 args->saved_regs,
643 args->entry_sp);
644 }
645
646 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
647 if (!log_is_enabled(Info, methodhandles)) return;
648 BLOCK_COMMENT(err_msg("trace_method_handle %s {", adaptername));
649 __ enter();
650 __ andptr(rsp, -16); // align stack if needed for FPU state
651 __ pusha();
652 __ mov(rbx, rsp); // for retrieving saved_regs
653 // Note: saved_regs must be in the entered frame for the
654 // robust stack walking implemented in trace_method_handle_stub.
655
656 // save FP result, valid at some call sites (adapter_opt_return_float, ...)
657 __ decrement(rsp, 2 * wordSize);
658 #ifdef _LP64
659 __ movdbl(Address(rsp, 0), xmm0);
660 #else
661 if (UseSSE >= 2) {
662 __ movdbl(Address(rsp, 0), xmm0);
663 } else if (UseSSE == 1) {
664 __ movflt(Address(rsp, 0), xmm0);
665 } else {
666 __ fst_d(Address(rsp, 0));
667 }
668 #endif // LP64
669
670 // Incoming state:
671 // rcx: method handle
672 //
673 // To avoid calling convention issues, build a record on the stack
674 // and pass the pointer to that instead.
675 __ push(rbp); // entry_sp (with extra align space)
676 __ push(rbx); // pusha saved_regs
677 __ push(rcx); // mh
678 __ push(rcx); // slot for adaptername
679 __ movptr(Address(rsp, 0), (intptr_t) adaptername, rscratch1);
680 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp);
681 __ increment(rsp, sizeof(MethodHandleStubArguments));
682
683 #ifdef _LP64
684 __ movdbl(xmm0, Address(rsp, 0));
685 #else
686 if (UseSSE >= 2) {
687 __ movdbl(xmm0, Address(rsp, 0));
688 } else if (UseSSE == 1) {
689 __ movflt(xmm0, Address(rsp, 0));
690 } else {
691 __ fld_d(Address(rsp, 0));
692 }
693 #endif // LP64
694 __ increment(rsp, 2 * wordSize);
695
696 __ popa();
697 __ leave();
698 BLOCK_COMMENT("} trace_method_handle");
699 }
700 #endif //PRODUCT