Sat, 01 Sep 2012 13:25:18 -0400
6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
1 /*
2 * Copyright (c) 1997, 2012, 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 */
25 #include "precompiled.hpp"
26 #include "interpreter/interpreter.hpp"
27 #include "interpreter/interpreterRuntime.hpp"
28 #include "memory/allocation.inline.hpp"
29 #include "prims/methodHandles.hpp"
31 #define __ _masm->
33 #ifdef PRODUCT
34 #define BLOCK_COMMENT(str) /* nothing */
35 #define STOP(error) stop(error)
36 #else
37 #define BLOCK_COMMENT(str) __ block_comment(str)
38 #define STOP(error) block_comment(error); __ stop(error)
39 #endif
41 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
43 // Workaround for C++ overloading nastiness on '0' for RegisterOrConstant.
44 static RegisterOrConstant constant(int value) {
45 return RegisterOrConstant(value);
46 }
48 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) {
49 if (VerifyMethodHandles)
50 verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class),
51 "MH argument is a Class");
52 __ movptr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes()));
53 }
55 #ifdef ASSERT
56 static int check_nonzero(const char* xname, int x) {
57 assert(x != 0, err_msg("%s should be nonzero", xname));
58 return x;
59 }
60 #define NONZERO(x) check_nonzero(#x, x)
61 #else //ASSERT
62 #define NONZERO(x) (x)
63 #endif //ASSERT
65 #ifdef ASSERT
66 void MethodHandles::verify_klass(MacroAssembler* _masm,
67 Register obj, SystemDictionary::WKID klass_id,
68 const char* error_message) {
69 Klass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id);
70 KlassHandle klass = SystemDictionary::well_known_klass(klass_id);
71 Register temp = rdi;
72 Register temp2 = noreg;
73 LP64_ONLY(temp2 = rscratch1); // used by MacroAssembler::cmpptr
74 Label L_ok, L_bad;
75 BLOCK_COMMENT("verify_klass {");
76 __ verify_oop(obj);
77 __ testptr(obj, obj);
78 __ jcc(Assembler::zero, L_bad);
79 __ push(temp); if (temp2 != noreg) __ push(temp2);
80 #define UNPUSH { if (temp2 != noreg) __ pop(temp2); __ pop(temp); }
81 __ load_klass(temp, obj);
82 __ cmpptr(temp, ExternalAddress((address) klass_addr));
83 __ jcc(Assembler::equal, L_ok);
84 intptr_t super_check_offset = klass->super_check_offset();
85 __ movptr(temp, Address(temp, super_check_offset));
86 __ cmpptr(temp, ExternalAddress((address) klass_addr));
87 __ jcc(Assembler::equal, L_ok);
88 UNPUSH;
89 __ bind(L_bad);
90 __ STOP(error_message);
91 __ BIND(L_ok);
92 UNPUSH;
93 BLOCK_COMMENT("} verify_klass");
94 }
96 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {
97 Label L;
98 BLOCK_COMMENT("verify_ref_kind {");
99 __ movl(temp, Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes())));
100 __ shrl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT);
101 __ andl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK);
102 __ cmpl(temp, ref_kind);
103 __ jcc(Assembler::equal, L);
104 { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);
105 jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);
106 if (ref_kind == JVM_REF_invokeVirtual ||
107 ref_kind == JVM_REF_invokeSpecial)
108 // could do this for all ref_kinds, but would explode assembly code size
109 trace_method_handle(_masm, buf);
110 __ STOP(buf);
111 }
112 BLOCK_COMMENT("} verify_ref_kind");
113 __ bind(L);
114 }
116 #endif //ASSERT
118 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
119 bool for_compiler_entry) {
120 assert(method == rbx, "interpreter calling convention");
121 __ verify_oop(method);
123 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
124 Label run_compiled_code;
125 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
126 // compiled code in threads for which the event is enabled. Check here for
127 // interp_only_mode if these events CAN be enabled.
128 #ifdef _LP64
129 Register rthread = r15_thread;
130 #else
131 Register rthread = temp;
132 __ get_thread(rthread);
133 #endif
134 // interp_only is an int, on little endian it is sufficient to test the byte only
135 // Is a cmpl faster?
136 __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0);
137 __ jccb(Assembler::zero, run_compiled_code);
138 __ jmp(Address(method, Method::interpreter_entry_offset()));
139 __ BIND(run_compiled_code);
140 }
142 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
143 Method::from_interpreted_offset();
144 __ jmp(Address(method, entry_offset));
145 }
147 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
148 Register recv, Register method_temp,
149 Register temp2,
150 bool for_compiler_entry) {
151 BLOCK_COMMENT("jump_to_lambda_form {");
152 // This is the initial entry point of a lazy method handle.
153 // After type checking, it picks up the invoker from the LambdaForm.
154 assert_different_registers(recv, method_temp, temp2);
155 assert(recv != noreg, "required register");
156 assert(method_temp == rbx, "required register for loading method");
158 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); });
160 // Load the invoker, as MH -> MH.form -> LF.vmentry
161 __ verify_oop(recv);
162 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())));
163 __ verify_oop(method_temp);
164 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())));
165 __ verify_oop(method_temp);
166 // the following assumes that a Method* is normally compressed in the vmtarget field:
167 __ movptr(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::vmtarget_offset_in_bytes())));
169 if (VerifyMethodHandles && !for_compiler_entry) {
170 // make sure recv is already on stack
171 __ load_sized_value(temp2,
172 Address(method_temp, Method::size_of_parameters_offset()),
173 sizeof(u2), /*is_signed*/ false);
174 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
175 Label L;
176 __ cmpptr(recv, __ argument_address(temp2, -1));
177 __ jcc(Assembler::equal, L);
178 __ movptr(rax, __ argument_address(temp2, -1));
179 __ STOP("receiver not on stack");
180 __ BIND(L);
181 }
183 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
184 BLOCK_COMMENT("} jump_to_lambda_form");
185 }
188 // Code generation
189 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
190 vmIntrinsics::ID iid) {
191 const bool not_for_compiler_entry = false; // this is the interpreter entry
192 assert(is_signature_polymorphic(iid), "expected invoke iid");
193 if (iid == vmIntrinsics::_invokeGeneric ||
194 iid == vmIntrinsics::_compiledLambdaForm) {
195 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
196 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
197 // They all allow an appendix argument.
198 __ hlt(); // empty stubs make SG sick
199 return NULL;
200 }
202 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
203 // rbx: Method*
204 // rdx: argument locator (parameter slot count, added to rsp)
205 // rcx: used as temp to hold mh or receiver
206 // rax, rdi: garbage temps, blown away
207 Register rdx_argp = rdx; // argument list ptr, live on error paths
208 Register rax_temp = rax;
209 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled
210 Register rbx_method = rbx; // eventual target of this invocation
212 address code_start = __ pc();
214 // here's where control starts out:
215 __ align(CodeEntryAlignment);
216 address entry_point = __ pc();
218 if (VerifyMethodHandles) {
219 Label L;
220 BLOCK_COMMENT("verify_intrinsic_id {");
221 __ cmpb(Address(rbx_method, Method::intrinsic_id_offset_in_bytes()), (int) iid);
222 __ jcc(Assembler::equal, L);
223 if (iid == vmIntrinsics::_linkToVirtual ||
224 iid == vmIntrinsics::_linkToSpecial) {
225 // could do this for all kinds, but would explode assembly code size
226 trace_method_handle(_masm, "bad Method*::intrinsic_id");
227 }
228 __ STOP("bad Method*::intrinsic_id");
229 __ bind(L);
230 BLOCK_COMMENT("} verify_intrinsic_id");
231 }
233 // First task: Find out how big the argument list is.
234 Address rdx_first_arg_addr;
235 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
236 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
237 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
238 __ load_sized_value(rdx_argp,
239 Address(rbx_method, Method::size_of_parameters_offset()),
240 sizeof(u2), /*is_signed*/ false);
241 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
242 rdx_first_arg_addr = __ argument_address(rdx_argp, -1);
243 } else {
244 DEBUG_ONLY(rdx_argp = noreg);
245 }
247 if (!is_signature_polymorphic_static(iid)) {
248 __ movptr(rcx_mh, rdx_first_arg_addr);
249 DEBUG_ONLY(rdx_argp = noreg);
250 }
252 // rdx_first_arg_addr is live!
254 if (TraceMethodHandles) {
255 const char* name = vmIntrinsics::name_at(iid);
256 if (*name == '_') name += 1;
257 const size_t len = strlen(name) + 50;
258 char* qname = NEW_C_HEAP_ARRAY(char, len, mtInternal);
259 const char* suffix = "";
260 if (vmIntrinsics::method_for(iid) == NULL ||
261 !vmIntrinsics::method_for(iid)->access_flags().is_public()) {
262 if (is_signature_polymorphic_static(iid))
263 suffix = "/static";
264 else
265 suffix = "/private";
266 }
267 jio_snprintf(qname, len, "MethodHandle::interpreter_entry::%s%s", name, suffix);
268 // note: stub look for mh in rcx
269 trace_method_handle(_masm, qname);
270 }
272 if (iid == vmIntrinsics::_invokeBasic) {
273 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);
275 } else {
276 // Adjust argument list by popping the trailing MemberName argument.
277 Register rcx_recv = noreg;
278 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
279 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
280 __ movptr(rcx_recv = rcx, rdx_first_arg_addr);
281 }
282 DEBUG_ONLY(rdx_argp = noreg);
283 Register rbx_member = rbx_method; // MemberName ptr; incoming method ptr is dead now
284 __ pop(rax_temp); // return address
285 __ pop(rbx_member); // extract last argument
286 __ push(rax_temp); // re-push return address
287 generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);
288 }
290 if (PrintMethodHandleStubs) {
291 address code_end = __ pc();
292 tty->print_cr("--------");
293 tty->print_cr("method handle interpreter entry for %s", vmIntrinsics::name_at(iid));
294 Disassembler::decode(code_start, code_end);
295 tty->cr();
296 }
298 return entry_point;
299 }
301 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
302 vmIntrinsics::ID iid,
303 Register receiver_reg,
304 Register member_reg,
305 bool for_compiler_entry) {
306 assert(is_signature_polymorphic(iid), "expected invoke iid");
307 Register rbx_method = rbx; // eventual target of this invocation
308 // temps used in this code are not used in *either* compiled or interpreted calling sequences
309 #ifdef _LP64
310 Register temp1 = rscratch1;
311 Register temp2 = rscratch2;
312 Register temp3 = rax;
313 if (for_compiler_entry) {
314 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment");
315 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
316 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
317 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
318 }
319 #else
320 Register temp1 = (for_compiler_entry ? rsi : rdx);
321 Register temp2 = rdi;
322 Register temp3 = rax;
323 if (for_compiler_entry) {
324 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : rcx), "only valid assignment");
325 assert_different_registers(temp1, rcx, rdx);
326 assert_different_registers(temp2, rcx, rdx);
327 assert_different_registers(temp3, rcx, rdx);
328 }
329 #endif
330 assert_different_registers(temp1, temp2, temp3, receiver_reg);
331 assert_different_registers(temp1, temp2, temp3, member_reg);
332 if (!for_compiler_entry)
333 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP
335 if (iid == vmIntrinsics::_invokeBasic) {
336 // indirect through MH.form.vmentry.vmtarget
337 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry);
339 } else {
340 // The method is a member invoker used by direct method handles.
341 if (VerifyMethodHandles) {
342 // make sure the trailing argument really is a MemberName (caller responsibility)
343 verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_invoke_MemberName),
344 "MemberName required for invokeVirtual etc.");
345 }
347 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()));
348 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()));
349 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::vmtarget_offset_in_bytes()));
351 Register temp1_recv_klass = temp1;
352 if (iid != vmIntrinsics::_linkToStatic) {
353 __ verify_oop(receiver_reg);
354 if (iid == vmIntrinsics::_linkToSpecial) {
355 // Don't actually load the klass; just null-check the receiver.
356 __ null_check(receiver_reg);
357 } else {
358 // load receiver klass itself
359 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes());
360 __ load_klass(temp1_recv_klass, receiver_reg);
361 __ verify_oop(temp1_recv_klass);
362 }
363 BLOCK_COMMENT("check_receiver {");
364 // The receiver for the MemberName must be in receiver_reg.
365 // Check the receiver against the MemberName.clazz
366 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
367 // Did not load it above...
368 __ load_klass(temp1_recv_klass, receiver_reg);
369 __ verify_oop(temp1_recv_klass);
370 }
371 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
372 Label L_ok;
373 Register temp2_defc = temp2;
374 __ load_heap_oop(temp2_defc, member_clazz);
375 load_klass_from_Class(_masm, temp2_defc);
376 __ verify_oop(temp2_defc);
377 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
378 // If we get here, the type check failed!
379 __ STOP("receiver class disagrees with MemberName.clazz");
380 __ bind(L_ok);
381 }
382 BLOCK_COMMENT("} check_receiver");
383 }
384 if (iid == vmIntrinsics::_linkToSpecial ||
385 iid == vmIntrinsics::_linkToStatic) {
386 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
387 }
389 // Live registers at this point:
390 // member_reg - MemberName that was the trailing argument
391 // temp1_recv_klass - klass of stacked receiver, if needed
392 // rsi/r13 - interpreter linkage (if interpreted)
393 // rcx, rdx, rsi, rdi, r8, r8 - compiler arguments (if compiled)
395 bool method_is_live = false;
396 switch (iid) {
397 case vmIntrinsics::_linkToSpecial:
398 if (VerifyMethodHandles) {
399 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
400 }
401 __ movptr(rbx_method, member_vmtarget);
402 method_is_live = true;
403 break;
405 case vmIntrinsics::_linkToStatic:
406 if (VerifyMethodHandles) {
407 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
408 }
409 __ movptr(rbx_method, member_vmtarget);
410 method_is_live = true;
411 break;
413 case vmIntrinsics::_linkToVirtual:
414 {
415 // same as TemplateTable::invokevirtual,
416 // minus the CP setup and profiling:
418 if (VerifyMethodHandles) {
419 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
420 }
422 // pick out the vtable index from the MemberName, and then we can discard it:
423 Register temp2_index = temp2;
424 __ movptr(temp2_index, member_vmindex);
426 if (VerifyMethodHandles) {
427 Label L_index_ok;
428 __ cmpl(temp2_index, 0);
429 __ jcc(Assembler::greaterEqual, L_index_ok);
430 __ STOP("no virtual index");
431 __ BIND(L_index_ok);
432 }
434 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
435 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
437 // get target Method* & entry point
438 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method);
439 method_is_live = true;
440 break;
441 }
443 case vmIntrinsics::_linkToInterface:
444 {
445 // same as TemplateTable::invokeinterface
446 // (minus the CP setup and profiling, with different argument motion)
447 if (VerifyMethodHandles) {
448 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
449 }
451 Register temp3_intf = temp3;
452 __ load_heap_oop(temp3_intf, member_clazz);
453 load_klass_from_Class(_masm, temp3_intf);
454 __ verify_oop(temp3_intf);
456 Register rbx_index = rbx_method;
457 __ movptr(rbx_index, member_vmindex);
458 if (VerifyMethodHandles) {
459 Label L;
460 __ cmpl(rbx_index, 0);
461 __ jcc(Assembler::greaterEqual, L);
462 __ STOP("invalid vtable index for MH.invokeInterface");
463 __ bind(L);
464 }
466 // given intf, index, and recv klass, dispatch to the implementation method
467 Label L_no_such_interface;
468 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
469 // note: next two args must be the same:
470 rbx_index, rbx_method,
471 temp2,
472 L_no_such_interface);
474 __ verify_oop(rbx_method);
475 jump_from_method_handle(_masm, rbx_method, temp2, for_compiler_entry);
476 __ hlt();
478 __ bind(L_no_such_interface);
479 __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
480 break;
481 }
483 default:
484 fatal(err_msg("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid)));
485 break;
486 }
488 if (method_is_live) {
489 // live at this point: rbx_method, rsi/r13 (if interpreted)
491 // After figuring out which concrete method to call, jump into it.
492 // Note that this works in the interpreter with no data motion.
493 // But the compiled version will require that rcx_recv be shifted out.
494 __ verify_oop(rbx_method);
495 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry);
496 }
497 }
498 }
500 #ifndef PRODUCT
501 void trace_method_handle_stub(const char* adaptername,
502 oop mh,
503 intptr_t* saved_regs,
504 intptr_t* entry_sp) {
505 // called as a leaf from native code: do not block the JVM!
506 bool has_mh = (strstr(adaptername, "/static") == NULL &&
507 strstr(adaptername, "linkTo") == NULL); // static linkers don't have MH
508 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx";
509 tty->print_cr("MH %s %s="PTR_FORMAT" sp="PTR_FORMAT,
510 adaptername, mh_reg_name,
511 mh, entry_sp);
513 if (Verbose) {
514 tty->print_cr("Registers:");
515 const int saved_regs_count = RegisterImpl::number_of_registers;
516 for (int i = 0; i < saved_regs_count; i++) {
517 Register r = as_Register(i);
518 // The registers are stored in reverse order on the stack (by pusha).
519 tty->print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
520 if ((i + 1) % 4 == 0) {
521 tty->cr();
522 } else {
523 tty->print(", ");
524 }
525 }
526 tty->cr();
528 {
529 // dumping last frame with frame::describe
531 JavaThread* p = JavaThread::active();
533 ResourceMark rm;
534 PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here
535 FrameValues values;
537 // Note: We want to allow trace_method_handle from any call site.
538 // While trace_method_handle creates a frame, it may be entered
539 // without a PC on the stack top (e.g. not just after a call).
540 // Walking that frame could lead to failures due to that invalid PC.
541 // => carefully detect that frame when doing the stack walking
543 // Current C frame
544 frame cur_frame = os::current_frame();
546 // Robust search of trace_calling_frame (independant of inlining).
547 // Assumes saved_regs comes from a pusha in the trace_calling_frame.
548 assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?");
549 frame trace_calling_frame = os::get_sender_for_C_frame(&cur_frame);
550 while (trace_calling_frame.fp() < saved_regs) {
551 trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame);
552 }
554 // safely create a frame and call frame::describe
555 intptr_t *dump_sp = trace_calling_frame.sender_sp();
556 intptr_t *dump_fp = trace_calling_frame.link();
558 bool walkable = has_mh; // whether the traced frame shoud be walkable
560 if (walkable) {
561 // The previous definition of walkable may have to be refined
562 // if new call sites cause the next frame constructor to start
563 // failing. Alternatively, frame constructors could be
564 // modified to support the current or future non walkable
565 // frames (but this is more intrusive and is not considered as
566 // part of this RFE, which will instead use a simpler output).
567 frame dump_frame = frame(dump_sp, dump_fp);
568 dump_frame.describe(values, 1);
569 } else {
570 // Stack may not be walkable (invalid PC above FP):
571 // Add descriptions without building a Java frame to avoid issues
572 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
573 values.describe(-1, dump_sp, "sp for #1");
574 }
575 values.describe(-1, entry_sp, "raw top of stack");
577 tty->print_cr("Stack layout:");
578 values.print(p);
579 }
580 if (has_mh && mh->is_oop()) {
581 mh->print();
582 if (java_lang_invoke_MethodHandle::is_instance(mh)) {
583 if (java_lang_invoke_MethodHandle::form_offset_in_bytes() != 0)
584 java_lang_invoke_MethodHandle::form(mh)->print();
585 }
586 }
587 }
588 }
590 // The stub wraps the arguments in a struct on the stack to avoid
591 // dealing with the different calling conventions for passing 6
592 // arguments.
593 struct MethodHandleStubArguments {
594 const char* adaptername;
595 oopDesc* mh;
596 intptr_t* saved_regs;
597 intptr_t* entry_sp;
598 };
599 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) {
600 trace_method_handle_stub(args->adaptername,
601 args->mh,
602 args->saved_regs,
603 args->entry_sp);
604 }
606 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
607 if (!TraceMethodHandles) return;
608 BLOCK_COMMENT("trace_method_handle {");
609 __ enter();
610 __ andptr(rsp, -16); // align stack if needed for FPU state
611 __ pusha();
612 __ mov(rbx, rsp); // for retreiving saved_regs
613 // Note: saved_regs must be in the entered frame for the
614 // robust stack walking implemented in trace_method_handle_stub.
616 // save FP result, valid at some call sites (adapter_opt_return_float, ...)
617 __ increment(rsp, -2 * wordSize);
618 if (UseSSE >= 2) {
619 __ movdbl(Address(rsp, 0), xmm0);
620 } else if (UseSSE == 1) {
621 __ movflt(Address(rsp, 0), xmm0);
622 } else {
623 __ fst_d(Address(rsp, 0));
624 }
626 // Incoming state:
627 // rcx: method handle
628 //
629 // To avoid calling convention issues, build a record on the stack
630 // and pass the pointer to that instead.
631 __ push(rbp); // entry_sp (with extra align space)
632 __ push(rbx); // pusha saved_regs
633 __ push(rcx); // mh
634 __ push(rcx); // slot for adaptername
635 __ movptr(Address(rsp, 0), (intptr_t) adaptername);
636 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp);
637 __ increment(rsp, sizeof(MethodHandleStubArguments));
639 if (UseSSE >= 2) {
640 __ movdbl(xmm0, Address(rsp, 0));
641 } else if (UseSSE == 1) {
642 __ movflt(xmm0, Address(rsp, 0));
643 } else {
644 __ fld_d(Address(rsp, 0));
645 }
646 __ increment(rsp, 2 * wordSize);
648 __ popa();
649 __ leave();
650 BLOCK_COMMENT("} trace_method_handle");
651 }
652 #endif //PRODUCT