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 const char* buf = "verify_ref_kind"; // avoid allocating new strings
116 if (ref_kind == JVM_REF_invokeVirtual ||
117 ref_kind == JVM_REF_invokeSpecial) {
118 // could do this for all ref_kinds, but would explode assembly code size
119 trace_method_handle(_masm, buf);
120 }
121 __ STOP(buf);
122 }
123 BLOCK_COMMENT("} verify_ref_kind");
124 __ bind(L);
125 }
126
127 #endif //ASSERT
128
129 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
130 bool for_compiler_entry) {
131 assert(method == rbx, "interpreter calling convention");
132
133 Label L_no_such_method;
134 __ testptr(rbx, rbx);
135 __ jcc(Assembler::zero, L_no_such_method);
136
137 __ verify_method_ptr(method);
138
139 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
140 Label run_compiled_code;
141 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
142 // compiled code in threads for which the event is enabled. Check here for
143 // interp_only_mode if these events CAN be enabled.
144 #ifdef _LP64
145 Register rthread = r15_thread;
146 #else
147 Register rthread = temp;
148 __ get_thread(rthread);
149 #endif
150 // interp_only is an int, on little endian it is sufficient to test the byte only
151 // Is a cmpl faster?
152 __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0);
153 __ jccb(Assembler::zero, run_compiled_code);
154 __ jmp(Address(method, Method::interpreter_entry_offset()));
155 __ BIND(run_compiled_code);
156 }
157
158 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
159 Method::from_interpreted_offset();
160 __ jmp(Address(method, entry_offset));
161
162 __ bind(L_no_such_method);
163 __ jump(RuntimeAddress(SharedRuntime::throw_AbstractMethodError_entry()));
164 }
165
166 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
167 Register recv, Register method_temp,
168 Register temp2,
169 bool for_compiler_entry) {
170 BLOCK_COMMENT("jump_to_lambda_form {");
171 // This is the initial entry point of a lazy method handle.
172 // After type checking, it picks up the invoker from the LambdaForm.
173 assert_different_registers(recv, method_temp, temp2);
174 assert(recv != noreg, "required register");
175 assert(method_temp == rbx, "required register for loading method");
176
177 // Load the invoker, as MH -> MH.form -> LF.vmentry
178 __ verify_oop(recv);
179 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset())), temp2);
180 __ verify_oop(method_temp);
181 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset())), temp2);
182 __ verify_oop(method_temp);
183 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset())), temp2);
184 __ verify_oop(method_temp);
185 __ access_load_at(T_ADDRESS, IN_HEAP, method_temp,
186 Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset())),
187 noreg, noreg);
188
189 if (VerifyMethodHandles && !for_compiler_entry) {
190 // make sure recv is already on stack
191 __ movptr(temp2, Address(method_temp, Method::const_offset()));
192 __ load_sized_value(temp2,
193 Address(temp2, ConstMethod::size_of_parameters_offset()),
194 sizeof(u2), /*is_signed*/ false);
195 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
196 Label L;
197 __ cmpoop(recv, __ argument_address(temp2, -1));
198 __ jcc(Assembler::equal, L);
199 __ movptr(rax, __ argument_address(temp2, -1));
200 __ STOP("receiver not on stack");
201 __ BIND(L);
202 }
203
204 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
205 BLOCK_COMMENT("} jump_to_lambda_form");
206 }
207
208 void MethodHandles::jump_to_native_invoker(MacroAssembler* _masm, Register nep_reg, Register temp_target) {
209 BLOCK_COMMENT("jump_to_native_invoker {");
210 assert_different_registers(nep_reg, temp_target);
211 assert(nep_reg != noreg, "required register");
212
213 // Load the invoker, as NEP -> .invoker
214 __ verify_oop(nep_reg);
215 __ access_load_at(T_ADDRESS, IN_HEAP, temp_target,
216 Address(nep_reg, NONZERO(jdk_internal_foreign_abi_NativeEntryPoint::downcall_stub_address_offset_in_bytes())),
217 noreg, noreg);
218
219 __ jmp(temp_target);
220 BLOCK_COMMENT("} jump_to_native_invoker");
221 }
222
223
224 // Code generation
225 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
226 vmIntrinsics::ID iid) {
227 const bool not_for_compiler_entry = false; // this is the interpreter entry
228 assert(is_signature_polymorphic(iid), "expected invoke iid");
229 if (iid == vmIntrinsics::_invokeGeneric ||
230 iid == vmIntrinsics::_compiledLambdaForm) {
231 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
232 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
233 // They all allow an appendix argument.
234 __ hlt(); // empty stubs make SG sick
235 return nullptr;
236 }
237
238 // No need in interpreter entry for linkToNative for now.
239 // Interpreter calls compiled entry through i2c.
240 if (iid == vmIntrinsics::_linkToNative) {
241 __ hlt();
242 return nullptr;
243 }
244
245 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
246 // rbx: Method*
247 // rdx: argument locator (parameter slot count, added to rsp)
248 // rcx: used as temp to hold mh or receiver
249 // rax, rdi: garbage temps, blown away
250 Register rdx_argp = rdx; // argument list ptr, live on error paths
251 Register rax_temp = rax;
252 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled
253 Register rbx_method = rbx; // eventual target of this invocation
254
255 // here's where control starts out:
256 __ align(CodeEntryAlignment);
257 address entry_point = __ pc();
258
259 if (VerifyMethodHandles) {
260 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
261
262 Label L;
263 BLOCK_COMMENT("verify_intrinsic_id {");
264 __ cmpw(Address(rbx_method, Method::intrinsic_id_offset()), (int) iid);
265 __ jcc(Assembler::equal, L);
266 if (iid == vmIntrinsics::_linkToVirtual ||
267 iid == vmIntrinsics::_linkToSpecial) {
268 // could do this for all kinds, but would explode assembly code size
269 trace_method_handle(_masm, "bad Method*::intrinsic_id");
270 }
271 __ STOP("bad Method*::intrinsic_id");
272 __ bind(L);
273 BLOCK_COMMENT("} verify_intrinsic_id");
274 }
275
276 // First task: Find out how big the argument list is.
277 Address rdx_first_arg_addr;
278 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
279 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
280 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
281 __ movptr(rdx_argp, Address(rbx_method, Method::const_offset()));
282 __ load_sized_value(rdx_argp,
283 Address(rdx_argp, ConstMethod::size_of_parameters_offset()),
284 sizeof(u2), /*is_signed*/ false);
285 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
286 rdx_first_arg_addr = __ argument_address(rdx_argp, -1);
287 } else {
288 DEBUG_ONLY(rdx_argp = noreg);
289 }
290
291 if (!is_signature_polymorphic_static(iid)) {
292 __ movptr(rcx_mh, rdx_first_arg_addr);
293 DEBUG_ONLY(rdx_argp = noreg);
294 }
295
296 // rdx_first_arg_addr is live!
297
298 trace_method_handle_interpreter_entry(_masm, iid);
299
300 if (iid == vmIntrinsics::_invokeBasic) {
301 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);
302
303 } else {
304 // Adjust argument list by popping the trailing MemberName argument.
305 Register rcx_recv = noreg;
306 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
307 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
308 __ movptr(rcx_recv = rcx, rdx_first_arg_addr);
309 }
310 DEBUG_ONLY(rdx_argp = noreg);
311 Register rbx_member = rbx_method; // MemberName ptr; incoming method ptr is dead now
312 __ pop(rax_temp); // return address
313 __ pop(rbx_member); // extract last argument
314 __ push(rax_temp); // re-push return address
315 generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);
316 }
317
318 return entry_point;
319 }
320
321 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
322 vmIntrinsics::ID iid,
323 Register receiver_reg,
324 Register member_reg,
325 bool for_compiler_entry) {
326 assert(is_signature_polymorphic(iid), "expected invoke iid");
327 Register rbx_method = rbx; // eventual target of this invocation
328 // temps used in this code are not used in *either* compiled or interpreted calling sequences
329 #ifdef _LP64
330 Register temp1 = rscratch1;
331 Register temp2 = rscratch2;
332 Register temp3 = rax;
333 if (for_compiler_entry) {
334 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic || iid == vmIntrinsics::_linkToNative ? noreg : j_rarg0), "only valid assignment");
335 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
336 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
337 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
338 }
339 #else
340 Register temp1 = (for_compiler_entry ? rsi : rdx);
341 Register temp2 = rdi;
342 Register temp3 = rax;
343 if (for_compiler_entry) {
344 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic || iid == vmIntrinsics::_linkToNative ? noreg : rcx), "only valid assignment");
345 assert_different_registers(temp1, rcx, rdx);
346 assert_different_registers(temp2, rcx, rdx);
347 assert_different_registers(temp3, rcx, rdx);
348 }
349 #endif
350 else {
351 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP
352 }
353 assert_different_registers(temp1, temp2, temp3, receiver_reg);
354 assert_different_registers(temp1, temp2, temp3, member_reg);
355
356 if (iid == vmIntrinsics::_invokeBasic) {
357 // indirect through MH.form.vmentry.vmtarget
358 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry);
359 } else if (iid == vmIntrinsics::_linkToNative) {
360 assert(for_compiler_entry, "only compiler entry is supported");
361 jump_to_native_invoker(_masm, member_reg, temp1);
362 } else {
363 // The method is a member invoker used by direct method handles.
364 if (VerifyMethodHandles) {
365 // make sure the trailing argument really is a MemberName (caller responsibility)
366 verify_klass(_masm, member_reg, VM_CLASS_ID(java_lang_invoke_MemberName),
367 "MemberName required for invokeVirtual etc.");
368 }
369
370 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset()));
371 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset()));
372 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset()));
373 Address vmtarget_method( rbx_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset()));
374
375 Register temp1_recv_klass = temp1;
376 if (iid != vmIntrinsics::_linkToStatic) {
377 __ verify_oop(receiver_reg);
378 if (iid == vmIntrinsics::_linkToSpecial) {
379 // Don't actually load the klass; just null-check the receiver.
380 __ null_check(receiver_reg);
381 } else {
382 // load receiver klass itself
383 __ load_klass(temp1_recv_klass, receiver_reg, temp2);
384 __ verify_klass_ptr(temp1_recv_klass);
385 }
386 BLOCK_COMMENT("check_receiver {");
387 // The receiver for the MemberName must be in receiver_reg.
388 // Check the receiver against the MemberName.clazz
389 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
390 // Did not load it above...
391 __ load_klass(temp1_recv_klass, receiver_reg, temp2);
392 __ verify_klass_ptr(temp1_recv_klass);
393 }
394 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
395 Label L_ok;
396 Register temp2_defc = temp2;
397 __ load_heap_oop(temp2_defc, member_clazz, temp3);
398 load_klass_from_Class(_masm, temp2_defc);
399 __ verify_klass_ptr(temp2_defc);
400 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
401 // If we get here, the type check failed!
402 __ STOP("receiver class disagrees with MemberName.clazz");
403 __ bind(L_ok);
404 }
405 BLOCK_COMMENT("} check_receiver");
406 }
407 if (iid == vmIntrinsics::_linkToSpecial ||
408 iid == vmIntrinsics::_linkToStatic) {
409 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
410 }
411
412 // Live registers at this point:
413 // member_reg - MemberName that was the trailing argument
414 // temp1_recv_klass - klass of stacked receiver, if needed
415 // rsi/r13 - interpreter linkage (if interpreted)
416 // rcx, rdx, rsi, rdi, r8 - compiler arguments (if compiled)
417
418 Label L_incompatible_class_change_error;
419 switch (iid) {
420 case vmIntrinsics::_linkToSpecial:
421 if (VerifyMethodHandles) {
422 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
423 }
424 __ load_heap_oop(rbx_method, member_vmtarget);
425 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
426 break;
427
428 case vmIntrinsics::_linkToStatic:
429 if (VerifyMethodHandles) {
430 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
431 }
432 __ load_heap_oop(rbx_method, member_vmtarget);
433 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
434 break;
435
436 case vmIntrinsics::_linkToVirtual:
437 {
438 // same as TemplateTable::invokevirtual,
439 // minus the CP setup and profiling:
440
441 if (VerifyMethodHandles) {
442 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
443 }
444
445 // pick out the vtable index from the MemberName, and then we can discard it:
446 Register temp2_index = temp2;
447 __ access_load_at(T_ADDRESS, IN_HEAP, temp2_index, member_vmindex, noreg, noreg);
448
449 if (VerifyMethodHandles) {
450 Label L_index_ok;
451 __ cmpl(temp2_index, 0);
452 __ jcc(Assembler::greaterEqual, L_index_ok);
453 __ STOP("no virtual index");
454 __ BIND(L_index_ok);
455 }
456
457 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
458 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
459
460 // get target Method* & entry point
461 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method);
462 break;
463 }
464
465 case vmIntrinsics::_linkToInterface:
466 {
467 // same as TemplateTable::invokeinterface
468 // (minus the CP setup and profiling, with different argument motion)
469 if (VerifyMethodHandles) {
470 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
471 }
472
473 Register temp3_intf = temp3;
474 __ load_heap_oop(temp3_intf, member_clazz);
475 load_klass_from_Class(_masm, temp3_intf);
476 __ verify_klass_ptr(temp3_intf);
477
478 Register rbx_index = rbx_method;
479 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_index, member_vmindex, noreg, noreg);
480 if (VerifyMethodHandles) {
481 Label L;
482 __ cmpl(rbx_index, 0);
483 __ jcc(Assembler::greaterEqual, L);
484 __ STOP("invalid vtable index for MH.invokeInterface");
485 __ bind(L);
486 }
487
488 // given intf, index, and recv klass, dispatch to the implementation method
489 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
490 // note: next two args must be the same:
491 rbx_index, rbx_method,
492 temp2,
493 L_incompatible_class_change_error);
494 break;
495 }
496
497 default:
498 fatal("unexpected intrinsic %d: %s", vmIntrinsics::as_int(iid), vmIntrinsics::name_at(iid));
499 break;
500 }
501
502 // Live at this point:
503 // rbx_method
504 // rsi/r13 (if interpreted)
505
506 // After figuring out which concrete method to call, jump into it.
507 // Note that this works in the interpreter with no data motion.
508 // But the compiled version will require that rcx_recv be shifted out.
509 __ verify_method_ptr(rbx_method);
510 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry);
511
512 if (iid == vmIntrinsics::_linkToInterface) {
513 __ bind(L_incompatible_class_change_error);
514 __ jump(RuntimeAddress(SharedRuntime::throw_IncompatibleClassChangeError_entry()));
515 }
516 }
517 }
518
519 #ifndef PRODUCT
520 void trace_method_handle_stub(const char* adaptername,
521 oopDesc* mh,
522 intptr_t* saved_regs,
523 intptr_t* entry_sp) {
524 // called as a leaf from native code: do not block the JVM!
525 bool has_mh = (strstr(adaptername, "/static") == nullptr &&
526 strstr(adaptername, "linkTo") == nullptr); // static linkers don't have MH
527 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx";
528 log_info(methodhandles)("MH %s %s=" PTR_FORMAT " sp=" PTR_FORMAT, adaptername, mh_reg_name, p2i(mh), p2i(entry_sp));
529
530 LogTarget(Trace, methodhandles) lt;
531 if (lt.is_enabled()) {
532 ResourceMark rm;
533 LogStream ls(lt);
534 ls.print_cr("Registers:");
535 const int saved_regs_count = Register::number_of_registers;
536 for (int i = 0; i < saved_regs_count; i++) {
537 Register r = as_Register(i);
538 // The registers are stored in reverse order on the stack (by pusha).
539 #ifdef AMD64
540 int num_regs = UseAPX ? 32 : 16;
541 assert(Register::available_gp_registers() == num_regs, "sanity");
542 if (r == rsp) {
543 // rsp is actually not stored by pusha(), compute the old rsp from saved_regs (rsp after pusha): saved_regs + 16 = old rsp
544 ls.print("%3s=" PTR_FORMAT, r->name(), (intptr_t)(&saved_regs[num_regs]));
545 } else {
546 ls.print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
547 }
548 #else
549 ls.print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
550 #endif
551 if ((i + 1) % 4 == 0) {
552 ls.cr();
553 } else {
554 ls.print(", ");
555 }
556 }
557 ls.cr();
558
559 // Note: We want to allow trace_method_handle from any call site.
560 // While trace_method_handle creates a frame, it may be entered
561 // without a PC on the stack top (e.g. not just after a call).
562 // Walking that frame could lead to failures due to that invalid PC.
563 // => carefully detect that frame when doing the stack walking
564
565 {
566 // dumping last frame with frame::describe
567
568 JavaThread* p = JavaThread::active();
569
570 // may not be needed by safer and unexpensive here
571 PreserveExceptionMark pem(Thread::current());
572 FrameValues values;
573
574 frame cur_frame = os::current_frame();
575
576 if (cur_frame.fp() != nullptr) { // not walkable
577
578 // Robust search of trace_calling_frame (independent of inlining).
579 // Assumes saved_regs comes from a pusha in the trace_calling_frame.
580 //
581 // We have to start the search from cur_frame, because trace_calling_frame may be it.
582 // It is guaranteed that trace_calling_frame is different from the top frame.
583 // But os::current_frame() does NOT return the top frame: it returns the next frame under it (caller's frame).
584 // (Due to inlining and tail call optimizations, caller's frame doesn't necessarily correspond to the immediate
585 // caller in the source code.)
586 assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?");
587 frame trace_calling_frame = cur_frame;
588 while (trace_calling_frame.fp() < saved_regs) {
589 assert(trace_calling_frame.cb() == nullptr, "not a C frame");
590 trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame);
591 }
592 assert(trace_calling_frame.sp() < saved_regs, "wrong frame");
593
594 // safely create a frame and call frame::describe
595 intptr_t *dump_sp = trace_calling_frame.sender_sp();
596 intptr_t *dump_fp = trace_calling_frame.link();
597
598 if (has_mh) {
599 // The previous definition of walkable may have to be refined
600 // if new call sites cause the next frame constructor to start
601 // failing. Alternatively, frame constructors could be
602 // modified to support the current or future non walkable
603 // frames (but this is more intrusive and is not considered as
604 // part of this RFE, which will instead use a simpler output).
605 frame dump_frame = frame(dump_sp, dump_fp);
606 dump_frame.describe(values, 1);
607 } else {
608 // Stack may not be walkable (invalid PC above FP):
609 // Add descriptions without building a Java frame to avoid issues
610 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
611 values.describe(-1, dump_sp, "sp for #1");
612 }
613 }
614 values.describe(-1, entry_sp, "raw top of stack");
615
616 ls.print_cr("Stack layout:");
617 values.print_on(p, &ls);
618 }
619 if (has_mh && oopDesc::is_oop(mh)) {
620 mh->print_on(&ls);
621 if (java_lang_invoke_MethodHandle::is_instance(mh)) {
622 java_lang_invoke_MethodHandle::form(mh)->print_on(&ls);
623 }
624 }
625 }
626 }
627
628 // The stub wraps the arguments in a struct on the stack to avoid
629 // dealing with the different calling conventions for passing 6
630 // arguments.
631 struct MethodHandleStubArguments {
632 const char* adaptername;
633 oopDesc* mh;
634 intptr_t* saved_regs;
635 intptr_t* entry_sp;
636 };
637 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) {
638 trace_method_handle_stub(args->adaptername,
639 args->mh,
640 args->saved_regs,
641 args->entry_sp);
642 }
643
644 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
645 if (!log_is_enabled(Info, methodhandles)) return;
646 BLOCK_COMMENT(err_msg("trace_method_handle %s {", adaptername));
647 __ enter();
648 __ andptr(rsp, -16); // align stack if needed for FPU state
649 __ pusha();
650 __ mov(rbx, rsp); // for retrieving saved_regs
651 // Note: saved_regs must be in the entered frame for the
652 // robust stack walking implemented in trace_method_handle_stub.
653
654 // save FP result, valid at some call sites (adapter_opt_return_float, ...)
655 __ decrement(rsp, 2 * wordSize);
656 #ifdef _LP64
657 __ movdbl(Address(rsp, 0), xmm0);
658 #else
659 if (UseSSE >= 2) {
660 __ movdbl(Address(rsp, 0), xmm0);
661 } else if (UseSSE == 1) {
662 __ movflt(Address(rsp, 0), xmm0);
663 } else {
664 __ fst_d(Address(rsp, 0));
665 }
666 #endif // LP64
667
668 // Incoming state:
669 // rcx: method handle
670 //
671 // To avoid calling convention issues, build a record on the stack
672 // and pass the pointer to that instead.
673 __ push(rbp); // entry_sp (with extra align space)
674 __ push(rbx); // pusha saved_regs
675 __ push(rcx); // mh
676 __ push(rcx); // slot for adaptername
677 __ movptr(Address(rsp, 0), (intptr_t) adaptername, rscratch1);
678 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp);
679 __ increment(rsp, sizeof(MethodHandleStubArguments));
680
681 #ifdef _LP64
682 __ movdbl(xmm0, Address(rsp, 0));
683 #else
684 if (UseSSE >= 2) {
685 __ movdbl(xmm0, Address(rsp, 0));
686 } else if (UseSSE == 1) {
687 __ movflt(xmm0, Address(rsp, 0));
688 } else {
689 __ fld_d(Address(rsp, 0));
690 }
691 #endif // LP64
692 __ increment(rsp, 2 * wordSize);
693
694 __ popa();
695 __ leave();
696 BLOCK_COMMENT("} trace_method_handle");
697 }
698 #endif //PRODUCT