1 /* 2 * Copyright (c) 1997, 2017, 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/javaClasses.inline.hpp" 28 #include "interpreter/interpreter.hpp" 29 #include "interpreter/interpreterRuntime.hpp" 30 #include "memory/allocation.inline.hpp" 31 #include "memory/resourceArea.hpp" 32 #include "prims/jvm.h" 33 #include "prims/methodHandles.hpp" 34 35 #define __ _masm-> 36 37 #ifdef PRODUCT 38 #define BLOCK_COMMENT(str) /* nothing */ 39 #define STOP(error) stop(error) 40 #else 41 #define BLOCK_COMMENT(str) __ block_comment(str) 42 #define STOP(error) block_comment(error); __ stop(error) 43 #endif 44 45 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":") 46 47 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) { 48 if (VerifyMethodHandles) 49 verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class), 50 "MH argument is a Class"); 51 __ movptr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes())); 52 } 53 54 #ifdef ASSERT 55 static int check_nonzero(const char* xname, int x) { 56 assert(x != 0, "%s should be nonzero", xname); 57 return x; 58 } 59 #define NONZERO(x) check_nonzero(#x, x) 60 #else //ASSERT 61 #define NONZERO(x) (x) 62 #endif //ASSERT 63 64 #ifdef ASSERT 65 void MethodHandles::verify_klass(MacroAssembler* _masm, 66 Register obj, SystemDictionary::WKID klass_id, 67 const char* error_message) { 68 InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id); 69 Klass* klass = SystemDictionary::well_known_klass(klass_id); 70 Register temp = rdi; 71 Register temp2 = noreg; 72 LP64_ONLY(temp2 = rscratch1); // used by MacroAssembler::cmpptr 73 Label L_ok, L_bad; 74 BLOCK_COMMENT("verify_klass {"); 75 __ verify_oop(obj); 76 __ testptr(obj, obj); 77 __ jcc(Assembler::zero, L_bad); 78 __ push(temp); if (temp2 != noreg) __ push(temp2); 79 #define UNPUSH { if (temp2 != noreg) __ pop(temp2); __ pop(temp); } 80 __ load_klass(temp, obj); 81 __ cmpptr(temp, ExternalAddress((address) klass_addr)); 82 __ jcc(Assembler::equal, L_ok); 83 intptr_t super_check_offset = klass->super_check_offset(); 84 __ movptr(temp, Address(temp, super_check_offset)); 85 __ cmpptr(temp, ExternalAddress((address) klass_addr)); 86 __ jcc(Assembler::equal, L_ok); 87 UNPUSH; 88 __ bind(L_bad); 89 __ STOP(error_message); 90 __ BIND(L_ok); 91 UNPUSH; 92 BLOCK_COMMENT("} verify_klass"); 93 } 94 95 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) { 96 Label L; 97 BLOCK_COMMENT("verify_ref_kind {"); 98 __ movl(temp, Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes()))); 99 __ shrl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT); 100 __ andl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK); 101 __ cmpl(temp, ref_kind); 102 __ jcc(Assembler::equal, L); 103 { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal); 104 jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind); 105 if (ref_kind == JVM_REF_invokeVirtual || 106 ref_kind == JVM_REF_invokeSpecial) 107 // could do this for all ref_kinds, but would explode assembly code size 108 trace_method_handle(_masm, buf); 109 __ STOP(buf); 110 } 111 BLOCK_COMMENT("} verify_ref_kind"); 112 __ bind(L); 113 } 114 115 #endif //ASSERT 116 117 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp, 118 bool for_compiler_entry) { 119 assert(method == rbx, "interpreter calling convention"); 120 121 Label L_no_such_method; 122 __ testptr(rbx, rbx); 123 __ jcc(Assembler::zero, L_no_such_method); 124 125 __ verify_method_ptr(method); 126 127 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) { 128 Label run_compiled_code; 129 // JVMTI events, such as single-stepping, are implemented partly by avoiding running 130 // compiled code in threads for which the event is enabled. Check here for 131 // interp_only_mode if these events CAN be enabled. 132 #ifdef _LP64 133 Register rthread = r15_thread; 134 #else 135 Register rthread = temp; 136 __ get_thread(rthread); 137 #endif 138 // interp_only is an int, on little endian it is sufficient to test the byte only 139 // Is a cmpl faster? 140 __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0); 141 __ jccb(Assembler::zero, run_compiled_code); 142 __ jmp(Address(method, Method::interpreter_entry_offset())); 143 __ BIND(run_compiled_code); 144 } 145 146 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() : 147 Method::from_interpreted_offset(); 148 __ jmp(Address(method, entry_offset)); 149 150 __ bind(L_no_such_method); 151 __ jump(RuntimeAddress(StubRoutines::throw_AbstractMethodError_entry())); 152 } 153 154 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm, 155 Register recv, Register method_temp, 156 Register temp2, 157 bool for_compiler_entry) { 158 BLOCK_COMMENT("jump_to_lambda_form {"); 159 // This is the initial entry point of a lazy method handle. 160 // After type checking, it picks up the invoker from the LambdaForm. 161 assert_different_registers(recv, method_temp, temp2); 162 assert(recv != noreg, "required register"); 163 assert(method_temp == rbx, "required register for loading method"); 164 165 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); }); 166 167 // Load the invoker, as MH -> MH.form -> LF.vmentry 168 oopDesc::bs()->interpreter_read_barrier(_masm, recv); 169 __ verify_oop(recv); 170 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes()))); 171 oopDesc::bs()->interpreter_read_barrier(_masm, method_temp); 172 __ verify_oop(method_temp); 173 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes()))); 174 oopDesc::bs()->interpreter_read_barrier(_masm, method_temp); 175 __ verify_oop(method_temp); 176 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()))); 177 oopDesc::bs()->interpreter_read_barrier(_masm, method_temp); 178 __ verify_oop(method_temp); 179 __ movptr(method_temp, Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes()))); 180 181 if (VerifyMethodHandles && !for_compiler_entry) { 182 // make sure recv is already on stack 183 __ movptr(temp2, Address(method_temp, Method::const_offset())); 184 __ load_sized_value(temp2, 185 Address(temp2, ConstMethod::size_of_parameters_offset()), 186 sizeof(u2), /*is_signed*/ false); 187 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), ""); 188 __ movptr(temp2, __ argument_address(temp2, -1)); 189 Label L; 190 __ cmpoopptr(recv, temp2); 191 __ jcc(Assembler::equal, L); 192 __ movptr(rax, temp2); 193 __ STOP("receiver not on stack"); 194 __ BIND(L); 195 } 196 197 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry); 198 BLOCK_COMMENT("} jump_to_lambda_form"); 199 } 200 201 202 // Code generation 203 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm, 204 vmIntrinsics::ID iid) { 205 const bool not_for_compiler_entry = false; // this is the interpreter entry 206 assert(is_signature_polymorphic(iid), "expected invoke iid"); 207 if (iid == vmIntrinsics::_invokeGeneric || 208 iid == vmIntrinsics::_compiledLambdaForm) { 209 // Perhaps surprisingly, the symbolic references visible to Java are not directly used. 210 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod. 211 // They all allow an appendix argument. 212 __ hlt(); // empty stubs make SG sick 213 return NULL; 214 } 215 216 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted) 217 // rbx: Method* 218 // rdx: argument locator (parameter slot count, added to rsp) 219 // rcx: used as temp to hold mh or receiver 220 // rax, rdi: garbage temps, blown away 221 Register rdx_argp = rdx; // argument list ptr, live on error paths 222 Register rax_temp = rax; 223 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled 224 Register rbx_method = rbx; // eventual target of this invocation 225 226 // here's where control starts out: 227 __ align(CodeEntryAlignment); 228 address entry_point = __ pc(); 229 230 if (VerifyMethodHandles) { 231 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2"); 232 233 Label L; 234 BLOCK_COMMENT("verify_intrinsic_id {"); 235 __ cmpw(Address(rbx_method, Method::intrinsic_id_offset_in_bytes()), (int) iid); 236 __ jcc(Assembler::equal, L); 237 if (iid == vmIntrinsics::_linkToVirtual || 238 iid == vmIntrinsics::_linkToSpecial) { 239 // could do this for all kinds, but would explode assembly code size 240 trace_method_handle(_masm, "bad Method*::intrinsic_id"); 241 } 242 __ STOP("bad Method*::intrinsic_id"); 243 __ bind(L); 244 BLOCK_COMMENT("} verify_intrinsic_id"); 245 } 246 247 // First task: Find out how big the argument list is. 248 Address rdx_first_arg_addr; 249 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid); 250 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic"); 251 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) { 252 __ movptr(rdx_argp, Address(rbx_method, Method::const_offset())); 253 __ load_sized_value(rdx_argp, 254 Address(rdx_argp, ConstMethod::size_of_parameters_offset()), 255 sizeof(u2), /*is_signed*/ false); 256 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), ""); 257 rdx_first_arg_addr = __ argument_address(rdx_argp, -1); 258 } else { 259 DEBUG_ONLY(rdx_argp = noreg); 260 } 261 262 if (!is_signature_polymorphic_static(iid)) { 263 __ movptr(rcx_mh, rdx_first_arg_addr); 264 DEBUG_ONLY(rdx_argp = noreg); 265 } 266 267 // rdx_first_arg_addr is live! 268 269 trace_method_handle_interpreter_entry(_masm, iid); 270 271 if (iid == vmIntrinsics::_invokeBasic) { 272 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry); 273 274 } else { 275 // Adjust argument list by popping the trailing MemberName argument. 276 Register rcx_recv = noreg; 277 if (MethodHandles::ref_kind_has_receiver(ref_kind)) { 278 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack. 279 __ movptr(rcx_recv = rcx, rdx_first_arg_addr); 280 } 281 DEBUG_ONLY(rdx_argp = noreg); 282 Register rbx_member = rbx_method; // MemberName ptr; incoming method ptr is dead now 283 __ pop(rax_temp); // return address 284 __ pop(rbx_member); // extract last argument 285 __ push(rax_temp); // re-push return address 286 generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry); 287 } 288 289 return entry_point; 290 } 291 292 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm, 293 vmIntrinsics::ID iid, 294 Register receiver_reg, 295 Register member_reg, 296 bool for_compiler_entry) { 297 assert(is_signature_polymorphic(iid), "expected invoke iid"); 298 Register rbx_method = rbx; // eventual target of this invocation 299 // temps used in this code are not used in *either* compiled or interpreted calling sequences 300 #ifdef _LP64 301 Register temp1 = rscratch1; 302 Register temp2 = rscratch2; 303 Register temp3 = rax; 304 if (for_compiler_entry) { 305 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment"); 306 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5); 307 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5); 308 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5); 309 } 310 #else 311 Register temp1 = (for_compiler_entry ? rsi : rdx); 312 Register temp2 = rdi; 313 Register temp3 = rax; 314 if (for_compiler_entry) { 315 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : rcx), "only valid assignment"); 316 assert_different_registers(temp1, rcx, rdx); 317 assert_different_registers(temp2, rcx, rdx); 318 assert_different_registers(temp3, rcx, rdx); 319 } 320 #endif 321 else { 322 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP 323 } 324 assert_different_registers(temp1, temp2, temp3, receiver_reg); 325 assert_different_registers(temp1, temp2, temp3, member_reg); 326 327 if (iid == vmIntrinsics::_invokeBasic) { 328 // indirect through MH.form.vmentry.vmtarget 329 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry); 330 331 } else { 332 // The method is a member invoker used by direct method handles. 333 if (VerifyMethodHandles) { 334 // make sure the trailing argument really is a MemberName (caller responsibility) 335 verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_invoke_MemberName), 336 "MemberName required for invokeVirtual etc."); 337 } 338 339 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes())); 340 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes())); 341 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes())); 342 Address vmtarget_method( rbx_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes())); 343 344 Register temp1_recv_klass = temp1; 345 if (iid != vmIntrinsics::_linkToStatic) { 346 __ verify_oop(receiver_reg); 347 if (iid == vmIntrinsics::_linkToSpecial) { 348 // Don't actually load the klass; just null-check the receiver. 349 __ null_check(receiver_reg); 350 } else { 351 // load receiver klass itself 352 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes()); 353 __ load_klass(temp1_recv_klass, receiver_reg); 354 __ verify_klass_ptr(temp1_recv_klass); 355 } 356 BLOCK_COMMENT("check_receiver {"); 357 // The receiver for the MemberName must be in receiver_reg. 358 // Check the receiver against the MemberName.clazz 359 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) { 360 // Did not load it above... 361 __ load_klass(temp1_recv_klass, receiver_reg); 362 __ verify_klass_ptr(temp1_recv_klass); 363 } 364 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) { 365 Label L_ok; 366 Register temp2_defc = temp2; 367 __ load_heap_oop(temp2_defc, member_clazz); 368 load_klass_from_Class(_masm, temp2_defc); 369 __ verify_klass_ptr(temp2_defc); 370 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok); 371 // If we get here, the type check failed! 372 __ STOP("receiver class disagrees with MemberName.clazz"); 373 __ bind(L_ok); 374 } 375 BLOCK_COMMENT("} check_receiver"); 376 } 377 if (iid == vmIntrinsics::_linkToSpecial || 378 iid == vmIntrinsics::_linkToStatic) { 379 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass 380 } 381 382 // Live registers at this point: 383 // member_reg - MemberName that was the trailing argument 384 // temp1_recv_klass - klass of stacked receiver, if needed 385 // rsi/r13 - interpreter linkage (if interpreted) 386 // rcx, rdx, rsi, rdi, r8 - compiler arguments (if compiled) 387 388 oopDesc::bs()->interpreter_read_barrier(_masm, member_reg); 389 Label L_incompatible_class_change_error; 390 switch (iid) { 391 case vmIntrinsics::_linkToSpecial: 392 if (VerifyMethodHandles) { 393 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3); 394 } 395 __ load_heap_oop(rbx_method, member_vmtarget); 396 oopDesc::bs()->interpreter_read_barrier(_masm, rbx_method); 397 __ movptr(rbx_method, vmtarget_method); 398 break; 399 400 case vmIntrinsics::_linkToStatic: 401 if (VerifyMethodHandles) { 402 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3); 403 } 404 __ load_heap_oop(rbx_method, member_vmtarget); 405 oopDesc::bs()->interpreter_read_barrier(_masm, rbx_method); 406 __ movptr(rbx_method, vmtarget_method); 407 break; 408 409 case vmIntrinsics::_linkToVirtual: 410 { 411 // same as TemplateTable::invokevirtual, 412 // minus the CP setup and profiling: 413 414 if (VerifyMethodHandles) { 415 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3); 416 } 417 418 // pick out the vtable index from the MemberName, and then we can discard it: 419 Register temp2_index = temp2; 420 __ movptr(temp2_index, member_vmindex); 421 422 if (VerifyMethodHandles) { 423 Label L_index_ok; 424 __ cmpl(temp2_index, 0); 425 __ jcc(Assembler::greaterEqual, L_index_ok); 426 __ STOP("no virtual index"); 427 __ BIND(L_index_ok); 428 } 429 430 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget 431 // at this point. And VerifyMethodHandles has already checked clazz, if needed. 432 433 // get target Method* & entry point 434 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method); 435 break; 436 } 437 438 case vmIntrinsics::_linkToInterface: 439 { 440 // same as TemplateTable::invokeinterface 441 // (minus the CP setup and profiling, with different argument motion) 442 if (VerifyMethodHandles) { 443 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3); 444 } 445 446 Register temp3_intf = temp3; 447 __ load_heap_oop(temp3_intf, member_clazz); 448 load_klass_from_Class(_masm, temp3_intf); 449 __ verify_klass_ptr(temp3_intf); 450 451 Register rbx_index = rbx_method; 452 __ movptr(rbx_index, member_vmindex); 453 if (VerifyMethodHandles) { 454 Label L; 455 __ cmpl(rbx_index, 0); 456 __ jcc(Assembler::greaterEqual, L); 457 __ STOP("invalid vtable index for MH.invokeInterface"); 458 __ bind(L); 459 } 460 461 // given intf, index, and recv klass, dispatch to the implementation method 462 __ lookup_interface_method(temp1_recv_klass, temp3_intf, 463 // note: next two args must be the same: 464 rbx_index, rbx_method, 465 temp2, 466 L_incompatible_class_change_error); 467 break; 468 } 469 470 default: 471 fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid)); 472 break; 473 } 474 475 // Live at this point: 476 // rbx_method 477 // rsi/r13 (if interpreted) 478 479 // After figuring out which concrete method to call, jump into it. 480 // Note that this works in the interpreter with no data motion. 481 // But the compiled version will require that rcx_recv be shifted out. 482 __ verify_method_ptr(rbx_method); 483 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry); 484 485 if (iid == vmIntrinsics::_linkToInterface) { 486 __ bind(L_incompatible_class_change_error); 487 __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry())); 488 } 489 } 490 } 491 492 #ifndef PRODUCT 493 void trace_method_handle_stub(const char* adaptername, 494 oop mh, 495 intptr_t* saved_regs, 496 intptr_t* entry_sp) { 497 // called as a leaf from native code: do not block the JVM! 498 bool has_mh = (strstr(adaptername, "/static") == NULL && 499 strstr(adaptername, "linkTo") == NULL); // static linkers don't have MH 500 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx"; 501 tty->print_cr("MH %s %s=" PTR_FORMAT " sp=" PTR_FORMAT, 502 adaptername, mh_reg_name, 503 p2i(mh), p2i(entry_sp)); 504 505 if (Verbose) { 506 tty->print_cr("Registers:"); 507 const int saved_regs_count = RegisterImpl::number_of_registers; 508 for (int i = 0; i < saved_regs_count; i++) { 509 Register r = as_Register(i); 510 // The registers are stored in reverse order on the stack (by pusha). 511 tty->print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]); 512 if ((i + 1) % 4 == 0) { 513 tty->cr(); 514 } else { 515 tty->print(", "); 516 } 517 } 518 tty->cr(); 519 520 { 521 // dumping last frame with frame::describe 522 523 JavaThread* p = JavaThread::active(); 524 525 ResourceMark rm; 526 PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here 527 FrameValues values; 528 529 // Note: We want to allow trace_method_handle from any call site. 530 // While trace_method_handle creates a frame, it may be entered 531 // without a PC on the stack top (e.g. not just after a call). 532 // Walking that frame could lead to failures due to that invalid PC. 533 // => carefully detect that frame when doing the stack walking 534 535 // Current C frame 536 frame cur_frame = os::current_frame(); 537 538 // Robust search of trace_calling_frame (independant of inlining). 539 // Assumes saved_regs comes from a pusha in the trace_calling_frame. 540 assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?"); 541 frame trace_calling_frame = os::get_sender_for_C_frame(&cur_frame); 542 while (trace_calling_frame.fp() < saved_regs) { 543 trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame); 544 } 545 546 // safely create a frame and call frame::describe 547 intptr_t *dump_sp = trace_calling_frame.sender_sp(); 548 intptr_t *dump_fp = trace_calling_frame.link(); 549 550 bool walkable = has_mh; // whether the traced frame shoud be walkable 551 552 if (walkable) { 553 // The previous definition of walkable may have to be refined 554 // if new call sites cause the next frame constructor to start 555 // failing. Alternatively, frame constructors could be 556 // modified to support the current or future non walkable 557 // frames (but this is more intrusive and is not considered as 558 // part of this RFE, which will instead use a simpler output). 559 frame dump_frame = frame(dump_sp, dump_fp); 560 dump_frame.describe(values, 1); 561 } else { 562 // Stack may not be walkable (invalid PC above FP): 563 // Add descriptions without building a Java frame to avoid issues 564 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>"); 565 values.describe(-1, dump_sp, "sp for #1"); 566 } 567 values.describe(-1, entry_sp, "raw top of stack"); 568 569 tty->print_cr("Stack layout:"); 570 values.print(p); 571 } 572 if (has_mh && mh->is_oop()) { 573 mh->print(); 574 if (java_lang_invoke_MethodHandle::is_instance(mh)) { 575 if (java_lang_invoke_MethodHandle::form_offset_in_bytes() != 0) 576 java_lang_invoke_MethodHandle::form(mh)->print(); 577 } 578 } 579 } 580 } 581 582 // The stub wraps the arguments in a struct on the stack to avoid 583 // dealing with the different calling conventions for passing 6 584 // arguments. 585 struct MethodHandleStubArguments { 586 const char* adaptername; 587 oopDesc* mh; 588 intptr_t* saved_regs; 589 intptr_t* entry_sp; 590 }; 591 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) { 592 trace_method_handle_stub(args->adaptername, 593 args->mh, 594 args->saved_regs, 595 args->entry_sp); 596 } 597 598 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) { 599 if (!TraceMethodHandles) return; 600 BLOCK_COMMENT("trace_method_handle {"); 601 __ enter(); 602 __ andptr(rsp, -16); // align stack if needed for FPU state 603 __ pusha(); 604 __ mov(rbx, rsp); // for retreiving saved_regs 605 // Note: saved_regs must be in the entered frame for the 606 // robust stack walking implemented in trace_method_handle_stub. 607 608 // save FP result, valid at some call sites (adapter_opt_return_float, ...) 609 __ increment(rsp, -2 * wordSize); 610 if (UseSSE >= 2) { 611 __ movdbl(Address(rsp, 0), xmm0); 612 } else if (UseSSE == 1) { 613 __ movflt(Address(rsp, 0), xmm0); 614 } else { 615 __ fst_d(Address(rsp, 0)); 616 } 617 618 // Incoming state: 619 // rcx: method handle 620 // 621 // To avoid calling convention issues, build a record on the stack 622 // and pass the pointer to that instead. 623 __ push(rbp); // entry_sp (with extra align space) 624 __ push(rbx); // pusha saved_regs 625 __ push(rcx); // mh 626 __ push(rcx); // slot for adaptername 627 __ movptr(Address(rsp, 0), (intptr_t) adaptername); 628 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp); 629 __ increment(rsp, sizeof(MethodHandleStubArguments)); 630 631 if (UseSSE >= 2) { 632 __ movdbl(xmm0, Address(rsp, 0)); 633 } else if (UseSSE == 1) { 634 __ movflt(xmm0, Address(rsp, 0)); 635 } else { 636 __ fld_d(Address(rsp, 0)); 637 } 638 __ increment(rsp, 2 * wordSize); 639 640 __ popa(); 641 __ leave(); 642 BLOCK_COMMENT("} trace_method_handle"); 643 } 644 #endif //PRODUCT