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); __ push(rscratch1); }
86 #define POP { __ 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 void MethodHandles::verify_method(MacroAssembler* _masm, Register method, Register temp, vmIntrinsics::ID iid) {
128 BLOCK_COMMENT("verify_method {");
129 __ verify_method_ptr(method);
130 if (VerifyMethodHandles) {
131 Label L_ok;
132 assert_different_registers(method, temp);
133
134 const Register method_holder = temp;
135 __ load_method_holder(method_holder, method);
136 __ push(method_holder); // keep holder around for diagnostic purposes
137
138 switch (iid) {
139 case vmIntrinsicID::_invokeBasic:
140 // Require compiled LambdaForm class to be fully initialized.
141 __ cmpb(Address(method_holder, InstanceKlass::init_state_offset()), InstanceKlass::fully_initialized);
142 __ jccb(Assembler::equal, L_ok);
143 break;
144
145 case vmIntrinsicID::_linkToStatic:
146 __ clinit_barrier(method_holder, &L_ok);
147 break;
148
149 case vmIntrinsicID::_linkToVirtual:
150 case vmIntrinsicID::_linkToSpecial:
151 case vmIntrinsicID::_linkToInterface:
152 // Class initialization check is too strong here. Just ensure that initialization has been initiated.
153 __ cmpb(Address(method_holder, InstanceKlass::init_state_offset()), InstanceKlass::being_initialized);
154 __ jcc(Assembler::greaterEqual, L_ok);
155
156 // init_state check failed, but it may be an abstract interface method
157 __ load_unsigned_short(temp, Address(method, Method::access_flags_offset()));
158 __ testl(temp, JVM_ACC_ABSTRACT);
159 __ jccb(Assembler::notZero, L_ok);
160 break;
161
162 default:
163 fatal("unexpected intrinsic %d: %s", vmIntrinsics::as_int(iid), vmIntrinsics::name_at(iid));
164 }
165
166 // clinit check failed for a concrete method
167 __ STOP("Method holder klass is not initialized");
168
169 __ BIND(L_ok);
170 __ pop(method_holder); // restore stack layout
171 }
172 BLOCK_COMMENT("} verify_method");
173 }
174 #endif // ASSERT
175
176 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
177 bool for_compiler_entry, vmIntrinsics::ID iid) {
178 assert(method == rbx, "interpreter calling convention");
179
180 Label L_no_such_method;
181 __ testptr(rbx, rbx);
182 __ jcc(Assembler::zero, L_no_such_method);
183
184 verify_method(_masm, method, temp, iid);
185
186 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
187 Label run_compiled_code;
188 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
189 // compiled code in threads for which the event is enabled. Check here for
190 // interp_only_mode if these events CAN be enabled.
191 // interp_only is an int, on little endian it is sufficient to test the byte only
192 // Is a cmpl faster?
193 __ cmpb(Address(r15_thread, JavaThread::interp_only_mode_offset()), 0);
194 __ jccb(Assembler::zero, run_compiled_code);
195 __ jmp(Address(method, Method::interpreter_entry_offset()));
196 __ BIND(run_compiled_code);
197 }
198
199 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
200 Method::from_interpreted_offset();
201 __ jmp(Address(method, entry_offset));
202
203 __ bind(L_no_such_method);
204 __ jump(RuntimeAddress(SharedRuntime::throw_AbstractMethodError_entry()));
205 }
206
207 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
208 Register recv, Register method_temp,
209 Register temp2,
210 bool for_compiler_entry) {
211 BLOCK_COMMENT("jump_to_lambda_form {");
212 // This is the initial entry point of a lazy method handle.
213 // After type checking, it picks up the invoker from the LambdaForm.
214 assert_different_registers(recv, method_temp, temp2);
215 assert(recv != noreg, "required register");
216 assert(method_temp == rbx, "required register for loading method");
217
218 // Load the invoker, as MH -> MH.form -> LF.vmentry
219 __ verify_oop(recv);
220 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset())), temp2);
221 __ verify_oop(method_temp);
222 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset())), temp2);
223 __ verify_oop(method_temp);
224 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset())), temp2);
225 __ verify_oop(method_temp);
226 __ access_load_at(T_ADDRESS, IN_HEAP, method_temp,
227 Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset())),
228 noreg);
229
230 if (VerifyMethodHandles && !for_compiler_entry) {
231 // make sure recv is already on stack
232 __ movptr(temp2, Address(method_temp, Method::const_offset()));
233 __ load_sized_value(temp2,
234 Address(temp2, ConstMethod::size_of_parameters_offset()),
235 sizeof(u2), /*is_signed*/ false);
236 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
237 Label L;
238 __ cmpoop(recv, __ argument_address(temp2, -1));
239 __ jcc(Assembler::equal, L);
240 __ movptr(rax, __ argument_address(temp2, -1));
241 __ STOP("receiver not on stack");
242 __ BIND(L);
243 }
244
245 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry, vmIntrinsics::_invokeBasic);
246 BLOCK_COMMENT("} jump_to_lambda_form");
247 }
248
249 void MethodHandles::jump_to_native_invoker(MacroAssembler* _masm, Register nep_reg, Register temp_target) {
250 BLOCK_COMMENT("jump_to_native_invoker {");
251 assert_different_registers(nep_reg, temp_target);
252 assert(nep_reg != noreg, "required register");
253
254 // Load the invoker, as NEP -> .invoker
255 __ verify_oop(nep_reg);
256 __ access_load_at(T_ADDRESS, IN_HEAP, temp_target,
257 Address(nep_reg, NONZERO(jdk_internal_foreign_abi_NativeEntryPoint::downcall_stub_address_offset_in_bytes())),
258 noreg);
259
260 __ jmp(temp_target);
261 BLOCK_COMMENT("} jump_to_native_invoker");
262 }
263
264
265 // Code generation
266 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
267 vmIntrinsics::ID iid) {
268 const bool not_for_compiler_entry = false; // this is the interpreter entry
269 assert(is_signature_polymorphic(iid), "expected invoke iid");
270 if (iid == vmIntrinsics::_invokeGeneric ||
271 iid == vmIntrinsics::_compiledLambdaForm) {
272 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
273 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
274 // They all allow an appendix argument.
275 __ hlt(); // empty stubs make SG sick
276 return nullptr;
277 }
278
279 // No need in interpreter entry for linkToNative for now.
280 // Interpreter calls compiled entry through i2c.
281 if (iid == vmIntrinsics::_linkToNative) {
282 __ hlt();
283 return nullptr;
284 }
285
286 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
287 // rbx: Method*
288 // rdx: argument locator (parameter slot count, added to rsp)
289 // rcx: used as temp to hold mh or receiver
290 // rax, rdi: garbage temps, blown away
291 Register rdx_argp = rdx; // argument list ptr, live on error paths
292 Register rax_temp = rax;
293 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled
294 Register rbx_method = rbx; // eventual target of this invocation
295
296 // here's where control starts out:
297 __ align(CodeEntryAlignment);
298 address entry_point = __ pc();
299
300 if (VerifyMethodHandles) {
301 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
302
303 Label L;
304 BLOCK_COMMENT("verify_intrinsic_id {");
305 __ cmpw(Address(rbx_method, Method::intrinsic_id_offset()), (int) iid);
306 __ jcc(Assembler::equal, L);
307 if (iid == vmIntrinsics::_linkToVirtual ||
308 iid == vmIntrinsics::_linkToSpecial) {
309 // could do this for all kinds, but would explode assembly code size
310 trace_method_handle(_masm, "bad Method*::intrinsic_id");
311 }
312 __ STOP("bad Method*::intrinsic_id");
313 __ bind(L);
314 BLOCK_COMMENT("} verify_intrinsic_id");
315 }
316
317 // First task: Find out how big the argument list is.
318 Address rdx_first_arg_addr;
319 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
320 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
321 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
322 __ movptr(rdx_argp, Address(rbx_method, Method::const_offset()));
323 __ load_sized_value(rdx_argp,
324 Address(rdx_argp, ConstMethod::size_of_parameters_offset()),
325 sizeof(u2), /*is_signed*/ false);
326 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
327 rdx_first_arg_addr = __ argument_address(rdx_argp, -1);
328 } else {
329 DEBUG_ONLY(rdx_argp = noreg);
330 }
331
332 if (!is_signature_polymorphic_static(iid)) {
333 __ movptr(rcx_mh, rdx_first_arg_addr);
334 DEBUG_ONLY(rdx_argp = noreg);
335 }
336
337 // rdx_first_arg_addr is live!
338
339 trace_method_handle_interpreter_entry(_masm, iid);
340
341 if (iid == vmIntrinsics::_invokeBasic) {
342 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);
343
344 } else {
345 // Adjust argument list by popping the trailing MemberName argument.
346 Register rcx_recv = noreg;
347 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
348 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
349 __ movptr(rcx_recv = rcx, rdx_first_arg_addr);
350 }
351 DEBUG_ONLY(rdx_argp = noreg);
352 Register rbx_member = rbx_method; // MemberName ptr; incoming method ptr is dead now
353 __ pop(rax_temp); // return address
354 __ pop(rbx_member); // extract last argument
355 __ push(rax_temp); // re-push return address
356 generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);
357 }
358
359 return entry_point;
360 }
361
362 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
363 vmIntrinsics::ID iid,
364 Register receiver_reg,
365 Register member_reg,
366 bool for_compiler_entry) {
367 assert(is_signature_polymorphic(iid), "expected invoke iid");
368 Register rbx_method = rbx; // eventual target of this invocation
369 // temps used in this code are not used in *either* compiled or interpreted calling sequences
370 Register temp1 = rscratch1;
371 Register temp2 = rscratch2;
372 Register temp3 = rax;
373 if (for_compiler_entry) {
374 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic || iid == vmIntrinsics::_linkToNative ? noreg : j_rarg0), "only valid assignment");
375 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
376 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
377 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
378 } else {
379 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP
380 }
381 assert_different_registers(temp1, temp2, temp3, receiver_reg);
382 assert_different_registers(temp1, temp2, temp3, member_reg);
383
384 if (iid == vmIntrinsics::_invokeBasic) {
385 // indirect through MH.form.vmentry.vmtarget
386 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry);
387 } else if (iid == vmIntrinsics::_linkToNative) {
388 assert(for_compiler_entry, "only compiler entry is supported");
389 jump_to_native_invoker(_masm, member_reg, temp1);
390 } else {
391 // The method is a member invoker used by direct method handles.
392 if (VerifyMethodHandles) {
393 // make sure the trailing argument really is a MemberName (caller responsibility)
394 verify_klass(_masm, member_reg, VM_CLASS_ID(java_lang_invoke_MemberName),
395 "MemberName required for invokeVirtual etc.");
396 }
397
398 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset()));
399 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset()));
400 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset()));
401 Address vmtarget_method( rbx_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset()));
402
403 Register temp1_recv_klass = temp1;
404 if (iid != vmIntrinsics::_linkToStatic) {
405 __ verify_oop(receiver_reg);
406 if (iid == vmIntrinsics::_linkToSpecial) {
407 // Don't actually load the klass; just null-check the receiver.
408 __ null_check(receiver_reg);
409 } else {
410 // load receiver klass itself
411 __ load_klass(temp1_recv_klass, receiver_reg, temp2);
412 __ verify_klass_ptr(temp1_recv_klass);
413 }
414 BLOCK_COMMENT("check_receiver {");
415 // The receiver for the MemberName must be in receiver_reg.
416 // Check the receiver against the MemberName.clazz
417 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
418 // Did not load it above...
419 __ load_klass(temp1_recv_klass, receiver_reg, temp2);
420 __ verify_klass_ptr(temp1_recv_klass);
421 }
422 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
423 Label L_ok;
424 Register temp2_defc = temp2;
425 __ load_heap_oop(temp2_defc, member_clazz, temp3);
426 load_klass_from_Class(_masm, temp2_defc);
427 __ verify_klass_ptr(temp2_defc);
428 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
429 // If we get here, the type check failed!
430 __ STOP("receiver class disagrees with MemberName.clazz");
431 __ bind(L_ok);
432 }
433 BLOCK_COMMENT("} check_receiver");
434 }
435 if (iid == vmIntrinsics::_linkToSpecial ||
436 iid == vmIntrinsics::_linkToStatic) {
437 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
438 }
439
440 // Live registers at this point:
441 // member_reg - MemberName that was the trailing argument
442 // temp1_recv_klass - klass of stacked receiver, if needed
443 // rsi/r13 - interpreter linkage (if interpreted)
444 // rcx, rdx, rsi, rdi, r8 - compiler arguments (if compiled)
445
446 Label L_incompatible_class_change_error;
447 switch (iid) {
448 case vmIntrinsics::_linkToSpecial:
449 if (VerifyMethodHandles) {
450 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
451 }
452 __ load_heap_oop(rbx_method, member_vmtarget);
453 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg);
454 break;
455
456 case vmIntrinsics::_linkToStatic:
457 if (VerifyMethodHandles) {
458 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
459 }
460 __ load_heap_oop(rbx_method, member_vmtarget);
461 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg);
462 break;
463
464 case vmIntrinsics::_linkToVirtual:
465 {
466 // same as TemplateTable::invokevirtual,
467 // minus the CP setup and profiling:
468
469 if (VerifyMethodHandles) {
470 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
471 }
472
473 // pick out the vtable index from the MemberName, and then we can discard it:
474 Register temp2_index = temp2;
475 __ access_load_at(T_ADDRESS, IN_HEAP, temp2_index, member_vmindex, noreg);
476
477 if (VerifyMethodHandles) {
478 Label L_index_ok;
479 __ cmpl(temp2_index, 0);
480 __ jcc(Assembler::greaterEqual, L_index_ok);
481 __ STOP("no virtual index");
482 __ BIND(L_index_ok);
483 }
484
485 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
486 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
487
488 // get target Method* & entry point
489 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method);
490 break;
491 }
492
493 case vmIntrinsics::_linkToInterface:
494 {
495 // same as TemplateTable::invokeinterface
496 // (minus the CP setup and profiling, with different argument motion)
497 if (VerifyMethodHandles) {
498 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
499 }
500
501 Register temp3_intf = temp3;
502 __ load_heap_oop(temp3_intf, member_clazz);
503 load_klass_from_Class(_masm, temp3_intf);
504 __ verify_klass_ptr(temp3_intf);
505
506 Register rbx_index = rbx_method;
507 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_index, member_vmindex, noreg);
508 if (VerifyMethodHandles) {
509 Label L;
510 __ cmpl(rbx_index, 0);
511 __ jcc(Assembler::greaterEqual, L);
512 __ STOP("invalid vtable index for MH.invokeInterface");
513 __ bind(L);
514 }
515
516 // given intf, index, and recv klass, dispatch to the implementation method
517 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
518 // note: next two args must be the same:
519 rbx_index, rbx_method,
520 temp2,
521 L_incompatible_class_change_error);
522 break;
523 }
524
525 default:
526 fatal("unexpected intrinsic %d: %s", vmIntrinsics::as_int(iid), vmIntrinsics::name_at(iid));
527 break;
528 }
529
530 // Live at this point:
531 // rbx_method
532 // rsi/r13 (if interpreted)
533
534 // After figuring out which concrete method to call, jump into it.
535 // Note that this works in the interpreter with no data motion.
536 // But the compiled version will require that rcx_recv be shifted out.
537 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry, iid);
538
539 if (iid == vmIntrinsics::_linkToInterface) {
540 __ bind(L_incompatible_class_change_error);
541 __ jump(RuntimeAddress(SharedRuntime::throw_IncompatibleClassChangeError_entry()));
542 }
543 }
544 }
545
546 #ifndef PRODUCT
547 void trace_method_handle_stub(const char* adaptername,
548 oopDesc* mh,
549 intptr_t* saved_regs,
550 intptr_t* entry_sp) {
551 // called as a leaf from native code: do not block the JVM!
552 bool has_mh = (strstr(adaptername, "/static") == nullptr &&
553 strstr(adaptername, "linkTo") == nullptr); // static linkers don't have MH
554 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx";
555 log_info(methodhandles)("MH %s %s=" PTR_FORMAT " sp=" PTR_FORMAT, adaptername, mh_reg_name, p2i(mh), p2i(entry_sp));
556
557 LogTarget(Trace, methodhandles) lt;
558 if (lt.is_enabled()) {
559 ResourceMark rm;
560 LogStream ls(lt);
561 ls.print_cr("Registers:");
562 const int saved_regs_count = Register::number_of_registers;
563 for (int i = 0; i < saved_regs_count; i++) {
564 Register r = as_Register(i);
565 // The registers are stored in reverse order on the stack (by pusha).
566 #ifdef AMD64
567 int num_regs = UseAPX ? 32 : 16;
568 assert(Register::available_gp_registers() == num_regs, "sanity");
569 if (r == rsp) {
570 // rsp is actually not stored by pusha(), compute the old rsp from saved_regs (rsp after pusha): saved_regs + 16 = old rsp
571 ls.print("%3s=" PTR_FORMAT, r->name(), (intptr_t)(&saved_regs[num_regs]));
572 } else {
573 ls.print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
574 }
575 #else
576 ls.print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
577 #endif
578 if ((i + 1) % 4 == 0) {
579 ls.cr();
580 } else {
581 ls.print(", ");
582 }
583 }
584 ls.cr();
585
586 // Note: We want to allow trace_method_handle from any call site.
587 // While trace_method_handle creates a frame, it may be entered
588 // without a PC on the stack top (e.g. not just after a call).
589 // Walking that frame could lead to failures due to that invalid PC.
590 // => carefully detect that frame when doing the stack walking
591
592 {
593 // dumping last frame with frame::describe
594
595 JavaThread* p = JavaThread::active();
596
597 // may not be needed by safer and unexpensive here
598 PreserveExceptionMark pem(Thread::current());
599 FrameValues values;
600
601 frame cur_frame = os::current_frame();
602
603 if (cur_frame.fp() != nullptr) { // not walkable
604
605 // Robust search of trace_calling_frame (independent of inlining).
606 // Assumes saved_regs comes from a pusha in the trace_calling_frame.
607 //
608 // We have to start the search from cur_frame, because trace_calling_frame may be it.
609 // It is guaranteed that trace_calling_frame is different from the top frame.
610 // But os::current_frame() does NOT return the top frame: it returns the next frame under it (caller's frame).
611 // (Due to inlining and tail call optimizations, caller's frame doesn't necessarily correspond to the immediate
612 // caller in the source code.)
613 assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?");
614 frame trace_calling_frame = cur_frame;
615 while (trace_calling_frame.fp() < saved_regs) {
616 assert(trace_calling_frame.cb() == nullptr, "not a C frame");
617 trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame);
618 }
619 assert(trace_calling_frame.sp() < saved_regs, "wrong frame");
620
621 // safely create a frame and call frame::describe
622 intptr_t *dump_sp = trace_calling_frame.sender_sp();
623 intptr_t *dump_fp = trace_calling_frame.link();
624
625 if (has_mh) {
626 // The previous definition of walkable may have to be refined
627 // if new call sites cause the next frame constructor to start
628 // failing. Alternatively, frame constructors could be
629 // modified to support the current or future non walkable
630 // frames (but this is more intrusive and is not considered as
631 // part of this RFE, which will instead use a simpler output).
632 frame dump_frame = frame(dump_sp, dump_fp);
633 dump_frame.describe(values, 1);
634 } else {
635 // Stack may not be walkable (invalid PC above FP):
636 // Add descriptions without building a Java frame to avoid issues
637 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
638 values.describe(-1, dump_sp, "sp for #1");
639 }
640 }
641 values.describe(-1, entry_sp, "raw top of stack");
642
643 ls.print_cr("Stack layout:");
644 values.print_on(p, &ls);
645 }
646 if (has_mh && oopDesc::is_oop(mh)) {
647 mh->print_on(&ls);
648 if (java_lang_invoke_MethodHandle::is_instance(mh)) {
649 java_lang_invoke_MethodHandle::form(mh)->print_on(&ls);
650 }
651 }
652 }
653 }
654
655 // The stub wraps the arguments in a struct on the stack to avoid
656 // dealing with the different calling conventions for passing 6
657 // arguments.
658 struct MethodHandleStubArguments {
659 const char* adaptername;
660 oopDesc* mh;
661 intptr_t* saved_regs;
662 intptr_t* entry_sp;
663 };
664 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) {
665 trace_method_handle_stub(args->adaptername,
666 args->mh,
667 args->saved_regs,
668 args->entry_sp);
669 }
670
671 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
672 if (!log_is_enabled(Info, methodhandles)) return;
673 BLOCK_COMMENT(err_msg("trace_method_handle %s {", adaptername));
674 __ enter();
675 __ andptr(rsp, -16); // align stack if needed for FPU state
676 __ pusha();
677 __ mov(rbx, rsp); // for retrieving saved_regs
678 // Note: saved_regs must be in the entered frame for the
679 // robust stack walking implemented in trace_method_handle_stub.
680
681 // save FP result, valid at some call sites (adapter_opt_return_float, ...)
682 __ decrement(rsp, 2 * wordSize);
683 __ movdbl(Address(rsp, 0), xmm0);
684
685 // Incoming state:
686 // rcx: method handle
687 //
688 // To avoid calling convention issues, build a record on the stack
689 // and pass the pointer to that instead.
690 __ push(rbp); // entry_sp (with extra align space)
691 __ push(rbx); // pusha saved_regs
692 __ push(rcx); // mh
693 __ push(rcx); // slot for adaptername
694 __ movptr(Address(rsp, 0), (intptr_t) adaptername, rscratch1);
695 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp);
696 __ increment(rsp, sizeof(MethodHandleStubArguments));
697
698 __ movdbl(xmm0, Address(rsp, 0));
699 __ increment(rsp, 2 * wordSize);
700
701 __ popa();
702 __ leave();
703 BLOCK_COMMENT("} trace_method_handle");
704 }
705 #endif //PRODUCT