1 /*
2 * Copyright (c) 1997, 2024, 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 const char* buf = "verify_ref_kind"; // avoid allocating new strings
117 if (ref_kind == JVM_REF_invokeVirtual ||
118 ref_kind == JVM_REF_invokeSpecial) {
119 // could do this for all ref_kinds, but would explode assembly code size
120 trace_method_handle(_masm, buf);
121 }
122 __ STOP(buf);
123 }
124 BLOCK_COMMENT("} verify_ref_kind");
125 __ bind(L);
126 }
127
128 #endif //ASSERT
129
130 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
131 bool for_compiler_entry) {
132 assert(method == rbx, "interpreter calling convention");
133
134 Label L_no_such_method;
135 __ testptr(rbx, rbx);
136 __ jcc(Assembler::zero, L_no_such_method);
137
138 __ verify_method_ptr(method);
139
140 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
141 Label run_compiled_code;
142 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
143 // compiled code in threads for which the event is enabled. Check here for
144 // interp_only_mode if these events CAN be enabled.
145 #ifdef _LP64
146 Register rthread = r15_thread;
147 #else
148 Register rthread = temp;
149 __ get_thread(rthread);
150 #endif
151 // interp_only is an int, on little endian it is sufficient to test the byte only
152 // Is a cmpl faster?
153 __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0);
154 __ jccb(Assembler::zero, run_compiled_code);
155 __ jmp(Address(method, Method::interpreter_entry_offset()));
156 __ BIND(run_compiled_code);
157 }
158
159 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
160 Method::from_interpreted_offset();
161 __ jmp(Address(method, entry_offset));
162
163 __ bind(L_no_such_method);
164 __ jump(RuntimeAddress(SharedRuntime::throw_AbstractMethodError_entry()));
165 }
166
167 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
168 Register recv, Register method_temp,
169 Register temp2,
170 bool for_compiler_entry) {
171 BLOCK_COMMENT("jump_to_lambda_form {");
172 // This is the initial entry point of a lazy method handle.
173 // After type checking, it picks up the invoker from the LambdaForm.
174 assert_different_registers(recv, method_temp, temp2);
175 assert(recv != noreg, "required register");
176 assert(method_temp == rbx, "required register for loading method");
177
178 // Load the invoker, as MH -> MH.form -> LF.vmentry
179 __ verify_oop(recv);
180 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset())), temp2);
181 __ verify_oop(method_temp);
182 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset())), temp2);
183 __ verify_oop(method_temp);
184 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset())), temp2);
185 __ verify_oop(method_temp);
186 __ access_load_at(T_ADDRESS, IN_HEAP, method_temp,
187 Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset())),
188 noreg, noreg);
189
190 if (VerifyMethodHandles && !for_compiler_entry) {
191 // make sure recv is already on stack
192 __ movptr(temp2, Address(method_temp, Method::const_offset()));
193 __ load_sized_value(temp2,
194 Address(temp2, ConstMethod::size_of_parameters_offset()),
195 sizeof(u2), /*is_signed*/ false);
196 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
197 Label L;
198 __ cmpoop(recv, __ argument_address(temp2, -1));
199 __ jcc(Assembler::equal, L);
200 __ movptr(rax, __ argument_address(temp2, -1));
201 __ STOP("receiver not on stack");
202 __ BIND(L);
203 }
204
205 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
206 BLOCK_COMMENT("} jump_to_lambda_form");
207 }
208
209 void MethodHandles::jump_to_native_invoker(MacroAssembler* _masm, Register nep_reg, Register temp_target) {
210 BLOCK_COMMENT("jump_to_native_invoker {");
211 assert_different_registers(nep_reg, temp_target);
212 assert(nep_reg != noreg, "required register");
213
214 // Load the invoker, as NEP -> .invoker
215 __ verify_oop(nep_reg);
216 __ access_load_at(T_ADDRESS, IN_HEAP, temp_target,
217 Address(nep_reg, NONZERO(jdk_internal_foreign_abi_NativeEntryPoint::downcall_stub_address_offset_in_bytes())),
218 noreg, noreg);
219
220 __ jmp(temp_target);
221 BLOCK_COMMENT("} jump_to_native_invoker");
222 }
223
224
225 // Code generation
226 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
227 vmIntrinsics::ID iid) {
228 const bool not_for_compiler_entry = false; // this is the interpreter entry
229 assert(is_signature_polymorphic(iid), "expected invoke iid");
230 if (iid == vmIntrinsics::_invokeGeneric ||
231 iid == vmIntrinsics::_compiledLambdaForm) {
232 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
233 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
234 // They all allow an appendix argument.
235 __ hlt(); // empty stubs make SG sick
236 return nullptr;
237 }
238
239 // No need in interpreter entry for linkToNative for now.
240 // Interpreter calls compiled entry through i2c.
241 if (iid == vmIntrinsics::_linkToNative) {
242 __ hlt();
243 return nullptr;
244 }
245
246 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
247 // rbx: Method*
248 // rdx: argument locator (parameter slot count, added to rsp)
249 // rcx: used as temp to hold mh or receiver
250 // rax, rdi: garbage temps, blown away
251 Register rdx_argp = rdx; // argument list ptr, live on error paths
252 Register rax_temp = rax;
253 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled
254 Register rbx_method = rbx; // eventual target of this invocation
255
256 // here's where control starts out:
257 __ align(CodeEntryAlignment);
258 address entry_point = __ pc();
259
260 if (VerifyMethodHandles) {
261 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
262
263 Label L;
264 BLOCK_COMMENT("verify_intrinsic_id {");
265 __ cmpw(Address(rbx_method, Method::intrinsic_id_offset()), (int) iid);
266 __ jcc(Assembler::equal, L);
267 if (iid == vmIntrinsics::_linkToVirtual ||
268 iid == vmIntrinsics::_linkToSpecial) {
269 // could do this for all kinds, but would explode assembly code size
270 trace_method_handle(_masm, "bad Method*::intrinsic_id");
271 }
272 __ STOP("bad Method*::intrinsic_id");
273 __ bind(L);
274 BLOCK_COMMENT("} verify_intrinsic_id");
275 }
276
277 // First task: Find out how big the argument list is.
278 Address rdx_first_arg_addr;
279 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
280 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
281 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
282 __ movptr(rdx_argp, Address(rbx_method, Method::const_offset()));
283 __ load_sized_value(rdx_argp,
284 Address(rdx_argp, ConstMethod::size_of_parameters_offset()),
285 sizeof(u2), /*is_signed*/ false);
286 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
287 rdx_first_arg_addr = __ argument_address(rdx_argp, -1);
288 } else {
289 DEBUG_ONLY(rdx_argp = noreg);
290 }
291
292 if (!is_signature_polymorphic_static(iid)) {
293 __ movptr(rcx_mh, rdx_first_arg_addr);
294 DEBUG_ONLY(rdx_argp = noreg);
295 }
296
297 // rdx_first_arg_addr is live!
298
299 trace_method_handle_interpreter_entry(_masm, iid);
300
301 if (iid == vmIntrinsics::_invokeBasic) {
302 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);
303
304 } else {
305 // Adjust argument list by popping the trailing MemberName argument.
306 Register rcx_recv = noreg;
307 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
308 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
309 __ movptr(rcx_recv = rcx, rdx_first_arg_addr);
310 }
311 DEBUG_ONLY(rdx_argp = noreg);
312 Register rbx_member = rbx_method; // MemberName ptr; incoming method ptr is dead now
313 __ pop(rax_temp); // return address
314 __ pop(rbx_member); // extract last argument
315 __ push(rax_temp); // re-push return address
316 generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);
317 }
318
319 return entry_point;
320 }
321
322 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
323 vmIntrinsics::ID iid,
324 Register receiver_reg,
325 Register member_reg,
326 bool for_compiler_entry) {
327 assert(is_signature_polymorphic(iid), "expected invoke iid");
328 Register rbx_method = rbx; // eventual target of this invocation
329 // temps used in this code are not used in *either* compiled or interpreted calling sequences
330 #ifdef _LP64
331 Register temp1 = rscratch1;
332 Register temp2 = rscratch2;
333 Register temp3 = rax;
334 if (for_compiler_entry) {
335 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic || iid == vmIntrinsics::_linkToNative ? noreg : j_rarg0), "only valid assignment");
336 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
337 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
338 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
339 }
340 #else
341 Register temp1 = (for_compiler_entry ? rsi : rdx);
342 Register temp2 = rdi;
343 Register temp3 = rax;
344 if (for_compiler_entry) {
345 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic || iid == vmIntrinsics::_linkToNative ? noreg : rcx), "only valid assignment");
346 assert_different_registers(temp1, rcx, rdx);
347 assert_different_registers(temp2, rcx, rdx);
348 assert_different_registers(temp3, rcx, rdx);
349 }
350 #endif
351 else {
352 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP
353 }
354 assert_different_registers(temp1, temp2, temp3, receiver_reg);
355 assert_different_registers(temp1, temp2, temp3, member_reg);
356
357 if (iid == vmIntrinsics::_invokeBasic) {
358 // indirect through MH.form.vmentry.vmtarget
359 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry);
360 } else if (iid == vmIntrinsics::_linkToNative) {
361 assert(for_compiler_entry, "only compiler entry is supported");
362 jump_to_native_invoker(_masm, member_reg, temp1);
363 } else {
364 // The method is a member invoker used by direct method handles.
365 if (VerifyMethodHandles) {
366 // make sure the trailing argument really is a MemberName (caller responsibility)
367 verify_klass(_masm, member_reg, VM_CLASS_ID(java_lang_invoke_MemberName),
368 "MemberName required for invokeVirtual etc.");
369 }
370
371 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset()));
372 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset()));
373 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset()));
374 Address vmtarget_method( rbx_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset()));
375
376 Register temp1_recv_klass = temp1;
377 if (iid != vmIntrinsics::_linkToStatic) {
378 __ verify_oop(receiver_reg);
379 if (iid == vmIntrinsics::_linkToSpecial) {
380 // Don't actually load the klass; just null-check the receiver.
381 __ null_check(receiver_reg);
382 } else {
383 // load receiver klass itself
384 __ load_klass(temp1_recv_klass, receiver_reg, temp2);
385 __ verify_klass_ptr(temp1_recv_klass);
386 }
387 BLOCK_COMMENT("check_receiver {");
388 // The receiver for the MemberName must be in receiver_reg.
389 // Check the receiver against the MemberName.clazz
390 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
391 // Did not load it above...
392 __ load_klass(temp1_recv_klass, receiver_reg, temp2);
393 __ verify_klass_ptr(temp1_recv_klass);
394 }
395 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
396 Label L_ok;
397 Register temp2_defc = temp2;
398 __ load_heap_oop(temp2_defc, member_clazz, temp3);
399 load_klass_from_Class(_masm, temp2_defc);
400 __ verify_klass_ptr(temp2_defc);
401 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
402 // If we get here, the type check failed!
403 __ STOP("receiver class disagrees with MemberName.clazz");
404 __ bind(L_ok);
405 }
406 BLOCK_COMMENT("} check_receiver");
407 }
408 if (iid == vmIntrinsics::_linkToSpecial ||
409 iid == vmIntrinsics::_linkToStatic) {
410 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
411 }
412
413 // Live registers at this point:
414 // member_reg - MemberName that was the trailing argument
415 // temp1_recv_klass - klass of stacked receiver, if needed
416 // rsi/r13 - interpreter linkage (if interpreted)
417 // rcx, rdx, rsi, rdi, r8 - compiler arguments (if compiled)
418
419 Label L_incompatible_class_change_error;
420 switch (iid) {
421 case vmIntrinsics::_linkToSpecial:
422 if (VerifyMethodHandles) {
423 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
424 }
425 __ load_heap_oop(rbx_method, member_vmtarget);
426 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
427 break;
428
429 case vmIntrinsics::_linkToStatic:
430 if (VerifyMethodHandles) {
431 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
432 }
433 __ load_heap_oop(rbx_method, member_vmtarget);
434 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg);
435 break;
436
437 case vmIntrinsics::_linkToVirtual:
438 {
439 // same as TemplateTable::invokevirtual,
440 // minus the CP setup and profiling:
441
442 if (VerifyMethodHandles) {
443 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
444 }
445
446 // pick out the vtable index from the MemberName, and then we can discard it:
447 Register temp2_index = temp2;
448 __ access_load_at(T_ADDRESS, IN_HEAP, temp2_index, member_vmindex, noreg, noreg);
449
450 if (VerifyMethodHandles) {
451 Label L_index_ok;
452 __ cmpl(temp2_index, 0);
453 __ jcc(Assembler::greaterEqual, L_index_ok);
454 __ STOP("no virtual index");
455 __ BIND(L_index_ok);
456 }
457
458 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
459 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
460
461 // get target Method* & entry point
462 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method);
463 break;
464 }
465
466 case vmIntrinsics::_linkToInterface:
467 {
468 // same as TemplateTable::invokeinterface
469 // (minus the CP setup and profiling, with different argument motion)
470 if (VerifyMethodHandles) {
471 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
472 }
473
474 Register temp3_intf = temp3;
475 __ load_heap_oop(temp3_intf, member_clazz);
476 load_klass_from_Class(_masm, temp3_intf);
477 __ verify_klass_ptr(temp3_intf);
478
479 Register rbx_index = rbx_method;
480 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_index, member_vmindex, noreg, noreg);
481 if (VerifyMethodHandles) {
482 Label L;
483 __ cmpl(rbx_index, 0);
484 __ jcc(Assembler::greaterEqual, L);
485 __ STOP("invalid vtable index for MH.invokeInterface");
486 __ bind(L);
487 }
488
489 // given intf, index, and recv klass, dispatch to the implementation method
490 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
491 // note: next two args must be the same:
492 rbx_index, rbx_method,
493 temp2,
494 L_incompatible_class_change_error);
495 break;
496 }
497
498 default:
499 fatal("unexpected intrinsic %d: %s", vmIntrinsics::as_int(iid), vmIntrinsics::name_at(iid));
500 break;
501 }
502
503 // Live at this point:
504 // rbx_method
505 // rsi/r13 (if interpreted)
506
507 // After figuring out which concrete method to call, jump into it.
508 // Note that this works in the interpreter with no data motion.
509 // But the compiled version will require that rcx_recv be shifted out.
510 __ verify_method_ptr(rbx_method);
511 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry);
512
513 if (iid == vmIntrinsics::_linkToInterface) {
514 __ bind(L_incompatible_class_change_error);
515 __ jump(RuntimeAddress(SharedRuntime::throw_IncompatibleClassChangeError_entry()));
516 }
517 }
518 }
519
520 #ifndef PRODUCT
521 void trace_method_handle_stub(const char* adaptername,
522 oopDesc* mh,
523 intptr_t* saved_regs,
524 intptr_t* entry_sp) {
525 // called as a leaf from native code: do not block the JVM!
526 bool has_mh = (strstr(adaptername, "/static") == nullptr &&
527 strstr(adaptername, "linkTo") == nullptr); // static linkers don't have MH
528 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx";
529 log_info(methodhandles)("MH %s %s=" PTR_FORMAT " sp=" PTR_FORMAT, adaptername, mh_reg_name, p2i(mh), p2i(entry_sp));
530
531 LogTarget(Trace, methodhandles) lt;
532 if (lt.is_enabled()) {
533 ResourceMark rm;
534 LogStream ls(lt);
535 ls.print_cr("Registers:");
536 const int saved_regs_count = Register::number_of_registers;
537 for (int i = 0; i < saved_regs_count; i++) {
538 Register r = as_Register(i);
539 // The registers are stored in reverse order on the stack (by pusha).
540 #ifdef AMD64
541 int num_regs = UseAPX ? 32 : 16;
542 assert(Register::available_gp_registers() == num_regs, "sanity");
543 if (r == rsp) {
544 // rsp is actually not stored by pusha(), compute the old rsp from saved_regs (rsp after pusha): saved_regs + 16 = old rsp
545 ls.print("%3s=" PTR_FORMAT, r->name(), (intptr_t)(&saved_regs[num_regs]));
546 } else {
547 ls.print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
548 }
549 #else
550 ls.print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
551 #endif
552 if ((i + 1) % 4 == 0) {
553 ls.cr();
554 } else {
555 ls.print(", ");
556 }
557 }
558 ls.cr();
559
560 // Note: We want to allow trace_method_handle from any call site.
561 // While trace_method_handle creates a frame, it may be entered
562 // without a PC on the stack top (e.g. not just after a call).
563 // Walking that frame could lead to failures due to that invalid PC.
564 // => carefully detect that frame when doing the stack walking
565
566 {
567 // dumping last frame with frame::describe
568
569 JavaThread* p = JavaThread::active();
570
571 // may not be needed by safer and unexpensive here
572 PreserveExceptionMark pem(Thread::current());
573 FrameValues values;
574
575 frame cur_frame = os::current_frame();
576
577 if (cur_frame.fp() != nullptr) { // not walkable
578
579 // Robust search of trace_calling_frame (independent of inlining).
580 // Assumes saved_regs comes from a pusha in the trace_calling_frame.
581 //
582 // We have to start the search from cur_frame, because trace_calling_frame may be it.
583 // It is guaranteed that trace_calling_frame is different from the top frame.
584 // But os::current_frame() does NOT return the top frame: it returns the next frame under it (caller's frame).
585 // (Due to inlining and tail call optimizations, caller's frame doesn't necessarily correspond to the immediate
586 // caller in the source code.)
587 assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?");
588 frame trace_calling_frame = cur_frame;
589 while (trace_calling_frame.fp() < saved_regs) {
590 assert(trace_calling_frame.cb() == nullptr, "not a C frame");
591 trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame);
592 }
593 assert(trace_calling_frame.sp() < saved_regs, "wrong frame");
594
595 // safely create a frame and call frame::describe
596 intptr_t *dump_sp = trace_calling_frame.sender_sp();
597 intptr_t *dump_fp = trace_calling_frame.link();
598
599 if (has_mh) {
600 // The previous definition of walkable may have to be refined
601 // if new call sites cause the next frame constructor to start
602 // failing. Alternatively, frame constructors could be
603 // modified to support the current or future non walkable
604 // frames (but this is more intrusive and is not considered as
605 // part of this RFE, which will instead use a simpler output).
606 frame dump_frame = frame(dump_sp, dump_fp);
607 dump_frame.describe(values, 1);
608 } else {
609 // Stack may not be walkable (invalid PC above FP):
610 // Add descriptions without building a Java frame to avoid issues
611 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
612 values.describe(-1, dump_sp, "sp for #1");
613 }
614 }
615 values.describe(-1, entry_sp, "raw top of stack");
616
617 ls.print_cr("Stack layout:");
618 values.print_on(p, &ls);
619 }
620 if (has_mh && oopDesc::is_oop(mh)) {
621 mh->print_on(&ls);
622 if (java_lang_invoke_MethodHandle::is_instance(mh)) {
623 java_lang_invoke_MethodHandle::form(mh)->print_on(&ls);
624 }
625 }
626 }
627 }
628
629 // The stub wraps the arguments in a struct on the stack to avoid
630 // dealing with the different calling conventions for passing 6
631 // arguments.
632 struct MethodHandleStubArguments {
633 const char* adaptername;
634 oopDesc* mh;
635 intptr_t* saved_regs;
636 intptr_t* entry_sp;
637 };
638 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) {
639 trace_method_handle_stub(args->adaptername,
640 args->mh,
641 args->saved_regs,
642 args->entry_sp);
643 }
644
645 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
646 if (!log_is_enabled(Info, methodhandles)) return;
647 BLOCK_COMMENT(err_msg("trace_method_handle %s {", adaptername));
648 __ enter();
649 __ andptr(rsp, -16); // align stack if needed for FPU state
650 __ pusha();
651 __ mov(rbx, rsp); // for retrieving saved_regs
652 // Note: saved_regs must be in the entered frame for the
653 // robust stack walking implemented in trace_method_handle_stub.
654
655 // save FP result, valid at some call sites (adapter_opt_return_float, ...)
656 __ decrement(rsp, 2 * wordSize);
657 #ifdef _LP64
658 __ movdbl(Address(rsp, 0), xmm0);
659 #else
660 if (UseSSE >= 2) {
661 __ movdbl(Address(rsp, 0), xmm0);
662 } else if (UseSSE == 1) {
663 __ movflt(Address(rsp, 0), xmm0);
664 } else {
665 __ fst_d(Address(rsp, 0));
666 }
667 #endif // LP64
668
669 // Incoming state:
670 // rcx: method handle
671 //
672 // To avoid calling convention issues, build a record on the stack
673 // and pass the pointer to that instead.
674 __ push(rbp); // entry_sp (with extra align space)
675 __ push(rbx); // pusha saved_regs
676 __ push(rcx); // mh
677 __ push(rcx); // slot for adaptername
678 __ movptr(Address(rsp, 0), (intptr_t) adaptername, rscratch1);
679 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp);
680 __ increment(rsp, sizeof(MethodHandleStubArguments));
681
682 #ifdef _LP64
683 __ movdbl(xmm0, Address(rsp, 0));
684 #else
685 if (UseSSE >= 2) {
686 __ movdbl(xmm0, Address(rsp, 0));
687 } else if (UseSSE == 1) {
688 __ movflt(xmm0, Address(rsp, 0));
689 } else {
690 __ fld_d(Address(rsp, 0));
691 }
692 #endif // LP64
693 __ increment(rsp, 2 * wordSize);
694
695 __ popa();
696 __ leave();
697 BLOCK_COMMENT("} trace_method_handle");
698 }
699 #endif //PRODUCT