Tue, 24 Jul 2012 10:51:00 -0700
7023639: JSR 292 method handle invocation needs a fast path for compiled code
6984705: JSR 292 method handle creation should not go through JNI
Summary: remove assembly code for JDK 7 chained method handles
Reviewed-by: jrose, twisti, kvn, mhaupt
Contributed-by: John Rose <john.r.rose@oracle.com>, Christian Thalinger <christian.thalinger@oracle.com>, Michael Haupt <michael.haupt@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, SystemDictionaryHandles::Class_klass(),
51 "MH argument is a Class");
52 __ load_heap_oop(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, KlassHandle klass,
68 const char* error_message) {
69 oop* klass_addr = klass.raw_value();
70 assert(klass_addr >= SystemDictionaryHandles::Object_klass().raw_value() &&
71 klass_addr <= SystemDictionaryHandles::Long_klass().raw_value(),
72 "must be one of the SystemDictionaryHandles");
73 Register temp = rdi;
74 Register temp2 = noreg;
75 LP64_ONLY(temp2 = rscratch1); // used by MacroAssembler::cmpptr
76 Label L_ok, L_bad;
77 BLOCK_COMMENT("verify_klass {");
78 __ verify_oop(obj);
79 __ testptr(obj, obj);
80 __ jcc(Assembler::zero, L_bad);
81 __ push(temp); if (temp2 != noreg) __ push(temp2);
82 #define UNPUSH { if (temp2 != noreg) __ pop(temp2); __ pop(temp); }
83 __ load_klass(temp, obj);
84 __ cmpptr(temp, ExternalAddress((address) klass_addr));
85 __ jcc(Assembler::equal, L_ok);
86 intptr_t super_check_offset = klass->super_check_offset();
87 __ movptr(temp, Address(temp, super_check_offset));
88 __ cmpptr(temp, ExternalAddress((address) klass_addr));
89 __ jcc(Assembler::equal, L_ok);
90 UNPUSH;
91 __ bind(L_bad);
92 __ STOP(error_message);
93 __ BIND(L_ok);
94 UNPUSH;
95 BLOCK_COMMENT("} verify_klass");
96 }
98 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {
99 Label L;
100 BLOCK_COMMENT("verify_ref_kind {");
101 __ movl(temp, Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes())));
102 __ shrl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT);
103 __ andl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK);
104 __ cmpl(temp, ref_kind);
105 __ jcc(Assembler::equal, L);
106 { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);
107 jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);
108 if (ref_kind == JVM_REF_invokeVirtual ||
109 ref_kind == JVM_REF_invokeSpecial)
110 // could do this for all ref_kinds, but would explode assembly code size
111 trace_method_handle(_masm, buf);
112 __ STOP(buf);
113 }
114 BLOCK_COMMENT("} verify_ref_kind");
115 __ bind(L);
116 }
118 #endif //ASSERT
120 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
121 bool for_compiler_entry) {
122 assert(method == rbx, "interpreter calling convention");
123 __ verify_oop(method);
125 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
126 Label run_compiled_code;
127 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
128 // compiled code in threads for which the event is enabled. Check here for
129 // interp_only_mode if these events CAN be enabled.
130 #ifdef _LP64
131 Register rthread = r15_thread;
132 #else
133 Register rthread = temp;
134 __ get_thread(rthread);
135 #endif
136 // interp_only is an int, on little endian it is sufficient to test the byte only
137 // Is a cmpl faster?
138 __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0);
139 __ jccb(Assembler::zero, run_compiled_code);
140 __ jmp(Address(method, methodOopDesc::interpreter_entry_offset()));
141 __ BIND(run_compiled_code);
142 }
144 const ByteSize entry_offset = for_compiler_entry ? methodOopDesc::from_compiled_offset() :
145 methodOopDesc::from_interpreted_offset();
146 __ jmp(Address(method, entry_offset));
147 }
149 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
150 Register recv, Register method_temp,
151 Register temp2,
152 bool for_compiler_entry) {
153 BLOCK_COMMENT("jump_to_lambda_form {");
154 // This is the initial entry point of a lazy method handle.
155 // After type checking, it picks up the invoker from the LambdaForm.
156 assert_different_registers(recv, method_temp, temp2);
157 assert(recv != noreg, "required register");
158 assert(method_temp == rbx, "required register for loading method");
160 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); });
162 // Load the invoker, as MH -> MH.form -> LF.vmentry
163 __ verify_oop(recv);
164 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())));
165 __ verify_oop(method_temp);
166 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())));
167 __ verify_oop(method_temp);
168 // the following assumes that a methodOop is normally compressed in the vmtarget field:
169 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::vmtarget_offset_in_bytes())));
170 __ verify_oop(method_temp);
172 if (VerifyMethodHandles && !for_compiler_entry) {
173 // make sure recv is already on stack
174 __ load_sized_value(temp2,
175 Address(method_temp, methodOopDesc::size_of_parameters_offset()),
176 sizeof(u2), /*is_signed*/ false);
177 // assert(sizeof(u2) == sizeof(methodOopDesc::_size_of_parameters), "");
178 Label L;
179 __ cmpptr(recv, __ argument_address(temp2, -1));
180 __ jcc(Assembler::equal, L);
181 __ movptr(rax, __ argument_address(temp2, -1));
182 __ STOP("receiver not on stack");
183 __ BIND(L);
184 }
186 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
187 BLOCK_COMMENT("} jump_to_lambda_form");
188 }
191 // Code generation
192 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
193 vmIntrinsics::ID iid) {
194 const bool not_for_compiler_entry = false; // this is the interpreter entry
195 assert(is_signature_polymorphic(iid), "expected invoke iid");
196 if (iid == vmIntrinsics::_invokeGeneric ||
197 iid == vmIntrinsics::_compiledLambdaForm) {
198 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
199 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
200 // They all allow an appendix argument.
201 __ hlt(); // empty stubs make SG sick
202 return NULL;
203 }
205 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
206 // rbx: methodOop
207 // rdx: argument locator (parameter slot count, added to rsp)
208 // rcx: used as temp to hold mh or receiver
209 // rax, rdi: garbage temps, blown away
210 Register rdx_argp = rdx; // argument list ptr, live on error paths
211 Register rax_temp = rax;
212 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled
213 Register rbx_method = rbx; // eventual target of this invocation
215 address code_start = __ pc();
217 // here's where control starts out:
218 __ align(CodeEntryAlignment);
219 address entry_point = __ pc();
221 if (VerifyMethodHandles) {
222 Label L;
223 BLOCK_COMMENT("verify_intrinsic_id {");
224 __ cmpb(Address(rbx_method, methodOopDesc::intrinsic_id_offset_in_bytes()), (int) iid);
225 __ jcc(Assembler::equal, L);
226 if (iid == vmIntrinsics::_linkToVirtual ||
227 iid == vmIntrinsics::_linkToSpecial) {
228 // could do this for all kinds, but would explode assembly code size
229 trace_method_handle(_masm, "bad methodOop::intrinsic_id");
230 }
231 __ STOP("bad methodOop::intrinsic_id");
232 __ bind(L);
233 BLOCK_COMMENT("} verify_intrinsic_id");
234 }
236 // First task: Find out how big the argument list is.
237 Address rdx_first_arg_addr;
238 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
239 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
240 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
241 __ load_sized_value(rdx_argp,
242 Address(rbx_method, methodOopDesc::size_of_parameters_offset()),
243 sizeof(u2), /*is_signed*/ false);
244 // assert(sizeof(u2) == sizeof(methodOopDesc::_size_of_parameters), "");
245 rdx_first_arg_addr = __ argument_address(rdx_argp, -1);
246 } else {
247 DEBUG_ONLY(rdx_argp = noreg);
248 }
250 if (!is_signature_polymorphic_static(iid)) {
251 __ movptr(rcx_mh, rdx_first_arg_addr);
252 DEBUG_ONLY(rdx_argp = noreg);
253 }
255 // rdx_first_arg_addr is live!
257 if (TraceMethodHandles) {
258 const char* name = vmIntrinsics::name_at(iid);
259 if (*name == '_') name += 1;
260 const size_t len = strlen(name) + 50;
261 char* qname = NEW_C_HEAP_ARRAY(char, len, mtInternal);
262 const char* suffix = "";
263 if (vmIntrinsics::method_for(iid) == NULL ||
264 !vmIntrinsics::method_for(iid)->access_flags().is_public()) {
265 if (is_signature_polymorphic_static(iid))
266 suffix = "/static";
267 else
268 suffix = "/private";
269 }
270 jio_snprintf(qname, len, "MethodHandle::interpreter_entry::%s%s", name, suffix);
271 // note: stub look for mh in rcx
272 trace_method_handle(_masm, qname);
273 }
275 if (iid == vmIntrinsics::_invokeBasic) {
276 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);
278 } else {
279 // Adjust argument list by popping the trailing MemberName argument.
280 Register rcx_recv = noreg;
281 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
282 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
283 __ movptr(rcx_recv = rcx, rdx_first_arg_addr);
284 }
285 DEBUG_ONLY(rdx_argp = noreg);
286 Register rbx_member = rbx_method; // MemberName ptr; incoming method ptr is dead now
287 __ pop(rax_temp); // return address
288 __ pop(rbx_member); // extract last argument
289 __ push(rax_temp); // re-push return address
290 generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);
291 }
293 if (PrintMethodHandleStubs) {
294 address code_end = __ pc();
295 tty->print_cr("--------");
296 tty->print_cr("method handle interpreter entry for %s", vmIntrinsics::name_at(iid));
297 Disassembler::decode(code_start, code_end);
298 tty->cr();
299 }
301 return entry_point;
302 }
304 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
305 vmIntrinsics::ID iid,
306 Register receiver_reg,
307 Register member_reg,
308 bool for_compiler_entry) {
309 assert(is_signature_polymorphic(iid), "expected invoke iid");
310 Register rbx_method = rbx; // eventual target of this invocation
311 // temps used in this code are not used in *either* compiled or interpreted calling sequences
312 #ifdef _LP64
313 Register temp1 = rscratch1;
314 Register temp2 = rscratch2;
315 Register temp3 = rax;
316 if (for_compiler_entry) {
317 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment");
318 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
319 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
320 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
321 }
322 #else
323 Register temp1 = (for_compiler_entry ? rsi : rdx);
324 Register temp2 = rdi;
325 Register temp3 = rax;
326 if (for_compiler_entry) {
327 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : rcx), "only valid assignment");
328 assert_different_registers(temp1, rcx, rdx);
329 assert_different_registers(temp2, rcx, rdx);
330 assert_different_registers(temp3, rcx, rdx);
331 }
332 #endif
333 assert_different_registers(temp1, temp2, temp3, receiver_reg);
334 assert_different_registers(temp1, temp2, temp3, member_reg);
335 if (!for_compiler_entry)
336 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP
338 if (iid == vmIntrinsics::_invokeBasic) {
339 // indirect through MH.form.vmentry.vmtarget
340 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry);
342 } else {
343 // The method is a member invoker used by direct method handles.
344 if (VerifyMethodHandles) {
345 // make sure the trailing argument really is a MemberName (caller responsibility)
346 verify_klass(_masm, member_reg, SystemDictionaryHandles::MemberName_klass(),
347 "MemberName required for invokeVirtual etc.");
348 }
350 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()));
351 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()));
352 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::vmtarget_offset_in_bytes()));
354 Register temp1_recv_klass = temp1;
355 if (iid != vmIntrinsics::_linkToStatic) {
356 __ verify_oop(receiver_reg);
357 if (iid == vmIntrinsics::_linkToSpecial) {
358 // Don't actually load the klass; just null-check the receiver.
359 __ null_check(receiver_reg);
360 } else {
361 // load receiver klass itself
362 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes());
363 __ load_klass(temp1_recv_klass, receiver_reg);
364 __ verify_oop(temp1_recv_klass);
365 }
366 BLOCK_COMMENT("check_receiver {");
367 // The receiver for the MemberName must be in receiver_reg.
368 // Check the receiver against the MemberName.clazz
369 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
370 // Did not load it above...
371 __ load_klass(temp1_recv_klass, receiver_reg);
372 __ verify_oop(temp1_recv_klass);
373 }
374 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
375 Label L_ok;
376 Register temp2_defc = temp2;
377 __ load_heap_oop(temp2_defc, member_clazz);
378 load_klass_from_Class(_masm, temp2_defc);
379 __ verify_oop(temp2_defc);
380 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
381 // If we get here, the type check failed!
382 __ STOP("receiver class disagrees with MemberName.clazz");
383 __ bind(L_ok);
384 }
385 BLOCK_COMMENT("} check_receiver");
386 }
387 if (iid == vmIntrinsics::_linkToSpecial ||
388 iid == vmIntrinsics::_linkToStatic) {
389 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
390 }
392 // Live registers at this point:
393 // member_reg - MemberName that was the trailing argument
394 // temp1_recv_klass - klass of stacked receiver, if needed
395 // rsi/r13 - interpreter linkage (if interpreted)
396 // rcx, rdx, rsi, rdi, r8, r8 - compiler arguments (if compiled)
398 bool method_is_live = false;
399 switch (iid) {
400 case vmIntrinsics::_linkToSpecial:
401 if (VerifyMethodHandles) {
402 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
403 }
404 __ load_heap_oop(rbx_method, member_vmtarget);
405 method_is_live = true;
406 break;
408 case vmIntrinsics::_linkToStatic:
409 if (VerifyMethodHandles) {
410 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
411 }
412 __ load_heap_oop(rbx_method, member_vmtarget);
413 method_is_live = true;
414 break;
416 case vmIntrinsics::_linkToVirtual:
417 {
418 // same as TemplateTable::invokevirtual,
419 // minus the CP setup and profiling:
421 if (VerifyMethodHandles) {
422 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
423 }
425 // pick out the vtable index from the MemberName, and then we can discard it:
426 Register temp2_index = temp2;
427 __ movptr(temp2_index, member_vmindex);
429 if (VerifyMethodHandles) {
430 Label L_index_ok;
431 __ cmpl(temp2_index, 0);
432 __ jcc(Assembler::greaterEqual, L_index_ok);
433 __ STOP("no virtual index");
434 __ BIND(L_index_ok);
435 }
437 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
438 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
440 // get target methodOop & entry point
441 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method);
442 method_is_live = true;
443 break;
444 }
446 case vmIntrinsics::_linkToInterface:
447 {
448 // same as TemplateTable::invokeinterface
449 // (minus the CP setup and profiling, with different argument motion)
450 if (VerifyMethodHandles) {
451 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
452 }
454 Register temp3_intf = temp3;
455 __ load_heap_oop(temp3_intf, member_clazz);
456 load_klass_from_Class(_masm, temp3_intf);
457 __ verify_oop(temp3_intf);
459 Register rbx_index = rbx_method;
460 __ movptr(rbx_index, member_vmindex);
461 if (VerifyMethodHandles) {
462 Label L;
463 __ cmpl(rbx_index, 0);
464 __ jcc(Assembler::greaterEqual, L);
465 __ STOP("invalid vtable index for MH.invokeInterface");
466 __ bind(L);
467 }
469 // given intf, index, and recv klass, dispatch to the implementation method
470 Label L_no_such_interface;
471 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
472 // note: next two args must be the same:
473 rbx_index, rbx_method,
474 temp2,
475 L_no_such_interface);
477 __ verify_oop(rbx_method);
478 jump_from_method_handle(_masm, rbx_method, temp2, for_compiler_entry);
479 __ hlt();
481 __ bind(L_no_such_interface);
482 __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
483 break;
484 }
486 default:
487 fatal(err_msg("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid)));
488 break;
489 }
491 if (method_is_live) {
492 // live at this point: rbx_method, rsi/r13 (if interpreted)
494 // After figuring out which concrete method to call, jump into it.
495 // Note that this works in the interpreter with no data motion.
496 // But the compiled version will require that rcx_recv be shifted out.
497 __ verify_oop(rbx_method);
498 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry);
499 }
500 }
501 }
503 #ifndef PRODUCT
504 void trace_method_handle_stub(const char* adaptername,
505 oop mh,
506 intptr_t* saved_regs,
507 intptr_t* entry_sp) {
508 // called as a leaf from native code: do not block the JVM!
509 bool has_mh = (strstr(adaptername, "/static") == NULL &&
510 strstr(adaptername, "linkTo") == NULL); // static linkers don't have MH
511 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx";
512 tty->print_cr("MH %s %s="PTR_FORMAT" sp="PTR_FORMAT,
513 adaptername, mh_reg_name,
514 mh, entry_sp);
516 if (Verbose) {
517 tty->print_cr("Registers:");
518 const int saved_regs_count = RegisterImpl::number_of_registers;
519 for (int i = 0; i < saved_regs_count; i++) {
520 Register r = as_Register(i);
521 // The registers are stored in reverse order on the stack (by pusha).
522 tty->print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
523 if ((i + 1) % 4 == 0) {
524 tty->cr();
525 } else {
526 tty->print(", ");
527 }
528 }
529 tty->cr();
531 {
532 // dumping last frame with frame::describe
534 JavaThread* p = JavaThread::active();
536 ResourceMark rm;
537 PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here
538 FrameValues values;
540 // Note: We want to allow trace_method_handle from any call site.
541 // While trace_method_handle creates a frame, it may be entered
542 // without a PC on the stack top (e.g. not just after a call).
543 // Walking that frame could lead to failures due to that invalid PC.
544 // => carefully detect that frame when doing the stack walking
546 // Current C frame
547 frame cur_frame = os::current_frame();
549 // Robust search of trace_calling_frame (independant of inlining).
550 // Assumes saved_regs comes from a pusha in the trace_calling_frame.
551 assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?");
552 frame trace_calling_frame = os::get_sender_for_C_frame(&cur_frame);
553 while (trace_calling_frame.fp() < saved_regs) {
554 trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame);
555 }
557 // safely create a frame and call frame::describe
558 intptr_t *dump_sp = trace_calling_frame.sender_sp();
559 intptr_t *dump_fp = trace_calling_frame.link();
561 bool walkable = has_mh; // whether the traced frame shoud be walkable
563 if (walkable) {
564 // The previous definition of walkable may have to be refined
565 // if new call sites cause the next frame constructor to start
566 // failing. Alternatively, frame constructors could be
567 // modified to support the current or future non walkable
568 // frames (but this is more intrusive and is not considered as
569 // part of this RFE, which will instead use a simpler output).
570 frame dump_frame = frame(dump_sp, dump_fp);
571 dump_frame.describe(values, 1);
572 } else {
573 // Stack may not be walkable (invalid PC above FP):
574 // Add descriptions without building a Java frame to avoid issues
575 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
576 values.describe(-1, dump_sp, "sp for #1");
577 }
578 values.describe(-1, entry_sp, "raw top of stack");
580 tty->print_cr("Stack layout:");
581 values.print(p);
582 }
583 if (has_mh && mh->is_oop()) {
584 mh->print();
585 if (java_lang_invoke_MethodHandle::is_instance(mh)) {
586 if (java_lang_invoke_MethodHandle::form_offset_in_bytes() != 0)
587 java_lang_invoke_MethodHandle::form(mh)->print();
588 }
589 }
590 }
591 }
593 // The stub wraps the arguments in a struct on the stack to avoid
594 // dealing with the different calling conventions for passing 6
595 // arguments.
596 struct MethodHandleStubArguments {
597 const char* adaptername;
598 oopDesc* mh;
599 intptr_t* saved_regs;
600 intptr_t* entry_sp;
601 };
602 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) {
603 trace_method_handle_stub(args->adaptername,
604 args->mh,
605 args->saved_regs,
606 args->entry_sp);
607 }
609 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
610 if (!TraceMethodHandles) return;
611 BLOCK_COMMENT("trace_method_handle {");
612 __ enter();
613 __ andptr(rsp, -16); // align stack if needed for FPU state
614 __ pusha();
615 __ mov(rbx, rsp); // for retreiving saved_regs
616 // Note: saved_regs must be in the entered frame for the
617 // robust stack walking implemented in trace_method_handle_stub.
619 // save FP result, valid at some call sites (adapter_opt_return_float, ...)
620 __ increment(rsp, -2 * wordSize);
621 if (UseSSE >= 2) {
622 __ movdbl(Address(rsp, 0), xmm0);
623 } else if (UseSSE == 1) {
624 __ movflt(Address(rsp, 0), xmm0);
625 } else {
626 __ fst_d(Address(rsp, 0));
627 }
629 // Incoming state:
630 // rcx: method handle
631 //
632 // To avoid calling convention issues, build a record on the stack
633 // and pass the pointer to that instead.
634 __ push(rbp); // entry_sp (with extra align space)
635 __ push(rbx); // pusha saved_regs
636 __ push(rcx); // mh
637 __ push(rcx); // slot for adaptername
638 __ movptr(Address(rsp, 0), (intptr_t) adaptername);
639 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp);
640 __ increment(rsp, sizeof(MethodHandleStubArguments));
642 if (UseSSE >= 2) {
643 __ movdbl(xmm0, Address(rsp, 0));
644 } else if (UseSSE == 1) {
645 __ movflt(xmm0, Address(rsp, 0));
646 } else {
647 __ fld_d(Address(rsp, 0));
648 }
649 __ increment(rsp, 2 * wordSize);
651 __ popa();
652 __ leave();
653 BLOCK_COMMENT("} trace_method_handle");
654 }
655 #endif //PRODUCT