1 /*
2 * Copyright (c) 1997, 2023, 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 "asm/macroAssembler.hpp"
27 #include "classfile/vmClasses.hpp"
28 #include "compiler/disassembler.hpp"
29 #include "classfile/javaClasses.inline.hpp"
30 #include "interpreter/interpreter.hpp"
31 #include "interpreter/interpreterRuntime.hpp"
32 #include "jvm.h"
33 #include "logging/log.hpp"
34 #include "logging/logStream.hpp"
35 #include "memory/allocation.inline.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "prims/jvmtiExport.hpp"
38 #include "prims/methodHandles.hpp"
39 #include "runtime/flags/flagSetting.hpp"
40 #include "runtime/frame.inline.hpp"
41 #include "runtime/stubRoutines.hpp"
42 #include "utilities/formatBuffer.hpp"
43 #include "utilities/preserveException.hpp"
44
45 #define __ Disassembler::hook<MacroAssembler>(__FILE__, __LINE__, _masm)->
46
47 #ifdef PRODUCT
48 #define BLOCK_COMMENT(str) /* nothing */
49 #define STOP(error) stop(error)
50 #else
51 #define BLOCK_COMMENT(str) __ block_comment(str)
52 #define STOP(error) block_comment(error); __ stop(error)
53 #endif
54
55 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
56
57 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) {
58 if (VerifyMethodHandles)
59 verify_klass(_masm, klass_reg, VM_CLASS_ID(java_lang_Class),
60 "MH argument is a Class");
61 __ movptr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset()));
62 }
63
64 #ifdef ASSERT
65 static int check_nonzero(const char* xname, int x) {
66 assert(x != 0, "%s should be nonzero", xname);
67 return x;
68 }
69 #define NONZERO(x) check_nonzero(#x, x)
70 #else //ASSERT
71 #define NONZERO(x) (x)
72 #endif //ASSERT
73
74 #ifdef ASSERT
75 void MethodHandles::verify_klass(MacroAssembler* _masm,
76 Register obj, vmClassID klass_id,
77 const char* error_message) {
78 InstanceKlass** klass_addr = vmClasses::klass_addr_at(klass_id);
79 Klass* klass = vmClasses::klass_at(klass_id);
80 Register temp = rdi;
81 Label L_ok, L_bad;
82 BLOCK_COMMENT("verify_klass {");
83 __ verify_oop(obj);
84 __ testptr(obj, obj);
85 __ jcc(Assembler::zero, L_bad);
86 #define PUSH { __ push(temp); LP64_ONLY( __ push(rscratch1); ) }
87 #define POP { LP64_ONLY( __ pop(rscratch1); ) __ pop(temp); }
88 PUSH;
89 __ load_klass(temp, obj, rscratch1);
90 __ cmpptr(temp, ExternalAddress((address) klass_addr), rscratch1);
91 __ jcc(Assembler::equal, L_ok);
92 intptr_t super_check_offset = klass->super_check_offset();
93 __ movptr(temp, Address(temp, super_check_offset));
94 __ cmpptr(temp, ExternalAddress((address) klass_addr), rscratch1);
95 __ jcc(Assembler::equal, L_ok);
96 POP;
97 __ bind(L_bad);
98 __ STOP(error_message);
99 __ BIND(L_ok);
100 POP;
101 BLOCK_COMMENT("} verify_klass");
102 #undef POP
103 #undef PUSH
104 }
105
106 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {
107 Label L;
108 BLOCK_COMMENT("verify_ref_kind {");
109 __ movl(temp, Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset())));
110 __ shrl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT);
111 __ andl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK);
112 __ cmpl(temp, ref_kind);
113 __ jcc(Assembler::equal, L);
114 { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);
115 jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);
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 __ STOP(buf);
121 }
122 BLOCK_COMMENT("} verify_ref_kind");
123 __ bind(L);
124 }
125
126 #endif //ASSERT
127
128 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
129 bool for_compiler_entry) {
130 assert(method == rbx, "interpreter calling convention");
131
132 Label L_no_such_method;
133 __ testptr(rbx, rbx);
134 __ jcc(Assembler::zero, L_no_such_method);
135
136 __ verify_method_ptr(method);
137
138 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
139 Label run_compiled_code;
140 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
141 // compiled code in threads for which the event is enabled. Check here for
142 // interp_only_mode if these events CAN be enabled.
143 #ifdef _LP64
144 Register rthread = r15_thread;
145 #else
146 Register rthread = temp;
147 __ get_thread(rthread);
148 #endif
149 // interp_only is an int, on little endian it is sufficient to test the byte only
150 // Is a cmpl faster?
151 __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0);
152 __ jccb(Assembler::zero, run_compiled_code);
153 __ jmp(Address(method, Method::interpreter_entry_offset()));
154 __ BIND(run_compiled_code);
155 }
156
157 // The following jump might pass an inline type argument that was erased to Object as oop to a
158 // callee that expects inline type arguments to be passed as fields. We need to call the compiled
159 // value entry (_code->inline_entry_point() or _adapter->c2i_inline_entry()) which will take care
160 // of translating between the calling conventions.
161 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_inline_offset() :
162 Method::from_interpreted_offset();
163 __ jmp(Address(method, entry_offset));
164
165 __ bind(L_no_such_method);
166 __ jump(RuntimeAddress(StubRoutines::throw_AbstractMethodError_entry()));
167 }
168
169 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
170 Register recv, Register method_temp,
171 Register temp2,
172 bool for_compiler_entry) {
173 BLOCK_COMMENT("jump_to_lambda_form {");
174 // This is the initial entry point of a lazy method handle.
175 // After type checking, it picks up the invoker from the LambdaForm.
176 assert_different_registers(recv, method_temp, temp2);
177 assert(recv != noreg, "required register");
178 assert(method_temp == rbx, "required register for loading method");
179
180 // Load the invoker, as MH -> MH.form -> LF.vmentry
181 __ verify_oop(recv);
182 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset())), temp2);
183 __ verify_oop(method_temp);
184 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset())), temp2);
185 __ verify_oop(method_temp);
186 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset())), temp2);
187 __ verify_oop(method_temp);
188 __ access_load_at(T_ADDRESS, IN_HEAP, method_temp,
189 Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset())),
190 noreg, noreg);
191
192 if (VerifyMethodHandles && !for_compiler_entry) {
193 // make sure recv is already on stack
194 __ movptr(temp2, Address(method_temp, Method::const_offset()));
195 __ load_sized_value(temp2,
196 Address(temp2, ConstMethod::size_of_parameters_offset()),
197 sizeof(u2), /*is_signed*/ false);
198 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
199 Label L;
200 __ cmpoop(recv, __ argument_address(temp2, -1));
201 __ jcc(Assembler::equal, L);
202 __ movptr(rax, __ argument_address(temp2, -1));
203 __ STOP("receiver not on stack");
204 __ BIND(L);
205 }
206
207 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
208 BLOCK_COMMENT("} jump_to_lambda_form");
209 }
210
211 void MethodHandles::jump_to_native_invoker(MacroAssembler* _masm, Register nep_reg, Register temp_target) {
212 BLOCK_COMMENT("jump_to_native_invoker {");
213 assert_different_registers(nep_reg, temp_target);
214 assert(nep_reg != noreg, "required register");
215
216 // Load the invoker, as NEP -> .invoker
217 __ verify_oop(nep_reg);
218 __ access_load_at(T_ADDRESS, IN_HEAP, temp_target,
219 Address(nep_reg, NONZERO(jdk_internal_foreign_abi_NativeEntryPoint::downcall_stub_address_offset_in_bytes())),
220 noreg, noreg);
221
222 __ jmp(temp_target);
223 BLOCK_COMMENT("} jump_to_native_invoker");
224 }
225
226
227 // Code generation
228 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
229 vmIntrinsics::ID iid) {
230 const bool not_for_compiler_entry = false; // this is the interpreter entry
231 assert(is_signature_polymorphic(iid), "expected invoke iid");
232 if (iid == vmIntrinsics::_invokeGeneric ||
233 iid == vmIntrinsics::_compiledLambdaForm) {
234 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
235 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
236 // They all allow an appendix argument.
237 __ hlt(); // empty stubs make SG sick
238 return nullptr;
239 }
240
241 // No need in interpreter entry for linkToNative for now.
242 // Interpreter calls compiled entry through i2c.
243 if (iid == vmIntrinsics::_linkToNative) {
244 __ hlt();
245 return nullptr;
246 }
247
248 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
249 // rbx: Method*
250 // rdx: argument locator (parameter slot count, added to rsp)
251 // rcx: used as temp to hold mh or receiver
252 // rax, rdi: garbage temps, blown away
253 Register rdx_argp = rdx; // argument list ptr, live on error paths
254 Register rax_temp = rax;
255 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled
256 Register rbx_method = rbx; // eventual target of this invocation
257
258 // here's where control starts out:
259 __ align(CodeEntryAlignment);
260 address entry_point = __ pc();
261
262 if (VerifyMethodHandles) {
263 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
264
265 Label L;
266 BLOCK_COMMENT("verify_intrinsic_id {");
267 __ cmpw(Address(rbx_method, Method::intrinsic_id_offset()), (int) iid);
268 __ jcc(Assembler::equal, L);
269 if (iid == vmIntrinsics::_linkToVirtual ||
270 iid == vmIntrinsics::_linkToSpecial) {
271 // could do this for all kinds, but would explode assembly code size
272 trace_method_handle(_masm, "bad Method*::intrinsic_id");
273 }
274 __ STOP("bad Method*::intrinsic_id");
275 __ bind(L);
276 BLOCK_COMMENT("} verify_intrinsic_id");
277 }
278
279 // First task: Find out how big the argument list is.
280 Address rdx_first_arg_addr;
281 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
282 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
283 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
284 __ movptr(rdx_argp, Address(rbx_method, Method::const_offset()));
285 __ load_sized_value(rdx_argp,
286 Address(rdx_argp, ConstMethod::size_of_parameters_offset()),
287 sizeof(u2), /*is_signed*/ false);
288 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
289 rdx_first_arg_addr = __ argument_address(rdx_argp, -1);
290 } else {
291 DEBUG_ONLY(rdx_argp = noreg);
292 }
293
294 if (!is_signature_polymorphic_static(iid)) {
295 __ movptr(rcx_mh, rdx_first_arg_addr);
296 DEBUG_ONLY(rdx_argp = noreg);
297 }
298
299 // rdx_first_arg_addr is live!
300
301 trace_method_handle_interpreter_entry(_masm, iid);
302
303 if (iid == vmIntrinsics::_invokeBasic) {
304 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);
305
306 } else {
307 // Adjust argument list by popping the trailing MemberName argument.
308 Register rcx_recv = noreg;
309 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
310 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
311 __ movptr(rcx_recv = rcx, rdx_first_arg_addr);
312 }
313 DEBUG_ONLY(rdx_argp = noreg);
314 Register rbx_member = rbx_method; // MemberName ptr; incoming method ptr is dead now
315 __ pop(rax_temp); // return address
316 __ pop(rbx_member); // extract last argument
317 __ push(rax_temp); // re-push return address
318 generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);
319 }
320
321 return entry_point;
322 }
323
324 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
325 vmIntrinsics::ID iid,
326 Register receiver_reg,
327 Register member_reg,
328 bool for_compiler_entry) {
329 assert(is_signature_polymorphic(iid), "expected invoke iid");
330 Register rbx_method = rbx; // eventual target of this invocation
331 // temps used in this code are not used in *either* compiled or interpreted calling sequences
332 #ifdef _LP64
333 Register temp1 = rscratch1;
334 Register temp2 = rscratch2;
335 Register temp3 = rax;
336 if (for_compiler_entry) {
337 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic || iid == vmIntrinsics::_linkToNative ? noreg : j_rarg0), "only valid assignment");
338 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
339 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
340 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
341 }
342 #else
343 Register temp1 = (for_compiler_entry ? rsi : rdx);
344 Register temp2 = rdi;
345 Register temp3 = rax;
346 if (for_compiler_entry) {
347 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic || iid == vmIntrinsics::_linkToNative ? noreg : rcx), "only valid assignment");
348 assert_different_registers(temp1, rcx, rdx);
349 assert_different_registers(temp2, rcx, rdx);
350 assert_different_registers(temp3, rcx, rdx);
351 }
352 #endif
353 else {
354 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP
355 }
356 assert_different_registers(temp1, temp2, temp3, receiver_reg);
357 assert_different_registers(temp1, temp2, temp3, member_reg);
358
359 if (iid == vmIntrinsics::_invokeBasic) {
360 // indirect through MH.form.vmentry.vmtarget
361 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry);
362 } else if (iid == vmIntrinsics::_linkToNative) {
363 assert(for_compiler_entry, "only compiler entry is supported");
364 jump_to_native_invoker(_masm, member_reg, temp1);
365 } else {
366 // The method is a member invoker used by direct method handles.
367 if (VerifyMethodHandles) {
368 // make sure the trailing argument really is a MemberName (caller responsibility)
369 verify_klass(_masm, member_reg, VM_CLASS_ID(java_lang_invoke_MemberName),
370 "MemberName required for invokeVirtual etc.");
371 }
372
373 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset()));
374 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset()));
375 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset()));
376 Address vmtarget_method( rbx_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset()));
377
378 Register temp1_recv_klass = temp1;
379 if (iid != vmIntrinsics::_linkToStatic) {
380 __ verify_oop(receiver_reg);
381 if (iid == vmIntrinsics::_linkToSpecial) {
382 // Don't actually load the klass; just null-check the receiver.
383 __ null_check(receiver_reg);
384 } else {
385 // load receiver klass itself
386 __ load_klass(temp1_recv_klass, receiver_reg, temp2);
387 __ verify_klass_ptr(temp1_recv_klass);
388 }
389 BLOCK_COMMENT("check_receiver {");
390 // The receiver for the MemberName must be in receiver_reg.
391 // Check the receiver against the MemberName.clazz
392 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
393 // Did not load it above...
394 __ load_klass(temp1_recv_klass, receiver_reg, temp2);
395 __ verify_klass_ptr(temp1_recv_klass);
396 }
397 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
398 Label L_ok;
399 Register temp2_defc = temp2;
400 __ load_heap_oop(temp2_defc, member_clazz, temp3);
401 load_klass_from_Class(_masm, temp2_defc);
402 __ verify_klass_ptr(temp2_defc);
403 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
404 // If we get here, the type check failed!
405 __ STOP("receiver class disagrees with MemberName.clazz");
406 __ bind(L_ok);
407 }
408 BLOCK_COMMENT("} check_receiver");
409 }
410 if (iid == vmIntrinsics::_linkToSpecial ||
411 iid == vmIntrinsics::_linkToStatic) {
412 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
413 }
414
415 // Live registers at this point:
416 // member_reg - MemberName that was the trailing argument
417 // temp1_recv_klass - klass of stacked receiver, if needed
418 // rsi/r13 - interpreter linkage (if interpreted)
419 // rcx, rdx, rsi, rdi, r8 - compiler arguments (if compiled)
420
421 Label L_incompatible_class_change_error;
422 switch (iid) {
423 case vmIntrinsics::_linkToSpecial:
424 if (VerifyMethodHandles) {
425 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
426 }
427 __ load_heap_oop(rbx_method, member_vmtarget);
428 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
429 break;
430
431 case vmIntrinsics::_linkToStatic:
432 if (VerifyMethodHandles) {
433 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
434 }
435 __ load_heap_oop(rbx_method, member_vmtarget);
436 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
437 break;
438
439 case vmIntrinsics::_linkToVirtual:
440 {
441 // same as TemplateTable::invokevirtual,
442 // minus the CP setup and profiling:
443
444 if (VerifyMethodHandles) {
445 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
446 }
447
448 // pick out the vtable index from the MemberName, and then we can discard it:
449 Register temp2_index = temp2;
450 __ access_load_at(T_ADDRESS, IN_HEAP, temp2_index, member_vmindex, noreg, noreg);
451
452 if (VerifyMethodHandles) {
453 Label L_index_ok;
454 __ cmpl(temp2_index, 0);
455 __ jcc(Assembler::greaterEqual, L_index_ok);
456 __ STOP("no virtual index");
457 __ BIND(L_index_ok);
458 }
459
460 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
461 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
462
463 // get target Method* & entry point
464 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method);
465 break;
466 }
467
468 case vmIntrinsics::_linkToInterface:
469 {
470 // same as TemplateTable::invokeinterface
471 // (minus the CP setup and profiling, with different argument motion)
472 if (VerifyMethodHandles) {
473 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
474 }
475
476 Register temp3_intf = temp3;
477 __ load_heap_oop(temp3_intf, member_clazz);
478 load_klass_from_Class(_masm, temp3_intf);
479 __ verify_klass_ptr(temp3_intf);
480
481 Register rbx_index = rbx_method;
482 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_index, member_vmindex, noreg, noreg);
483 if (VerifyMethodHandles) {
484 Label L;
485 __ cmpl(rbx_index, 0);
486 __ jcc(Assembler::greaterEqual, L);
487 __ STOP("invalid vtable index for MH.invokeInterface");
488 __ bind(L);
489 }
490
491 // given intf, index, and recv klass, dispatch to the implementation method
492 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
493 // note: next two args must be the same:
494 rbx_index, rbx_method,
495 temp2,
496 L_incompatible_class_change_error);
497 break;
498 }
499
500 default:
501 fatal("unexpected intrinsic %d: %s", vmIntrinsics::as_int(iid), vmIntrinsics::name_at(iid));
502 break;
503 }
504
505 // Live at this point:
506 // rbx_method
507 // rsi/r13 (if interpreted)
508
509 // After figuring out which concrete method to call, jump into it.
510 // Note that this works in the interpreter with no data motion.
511 // But the compiled version will require that rcx_recv be shifted out.
512 __ verify_method_ptr(rbx_method);
513 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry);
514
515 if (iid == vmIntrinsics::_linkToInterface) {
516 __ bind(L_incompatible_class_change_error);
517 __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
518 }
519 }
520 }
521
522 #ifndef PRODUCT
523 void trace_method_handle_stub(const char* adaptername,
524 oopDesc* mh,
525 intptr_t* saved_regs,
526 intptr_t* entry_sp) {
527 // called as a leaf from native code: do not block the JVM!
528 bool has_mh = (strstr(adaptername, "/static") == nullptr &&
529 strstr(adaptername, "linkTo") == nullptr); // static linkers don't have MH
530 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx";
531 log_info(methodhandles)("MH %s %s=" PTR_FORMAT " sp=" PTR_FORMAT, adaptername, mh_reg_name, p2i(mh), p2i(entry_sp));
532
533 LogTarget(Trace, methodhandles) lt;
534 if (lt.is_enabled()) {
535 ResourceMark rm;
536 LogStream ls(lt);
537 ls.print_cr("Registers:");
538 const int saved_regs_count = Register::number_of_registers;
539 for (int i = 0; i < saved_regs_count; i++) {
540 Register r = as_Register(i);
541 // The registers are stored in reverse order on the stack (by pusha).
542 #ifdef AMD64
543 assert(Register::number_of_registers == 16, "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[16]));
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() != 0) { // 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