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