1 /* 2 * Copyright (c) 1997, 2018, 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 "jvm.h" 27 #include "asm/macroAssembler.hpp" 28 #include "compiler/disassembler.hpp" 29 #include "classfile/javaClasses.inline.hpp" 30 #include "interpreter/interpreter.hpp" 31 #include "interpreter/interpreterRuntime.hpp" 32 #include "memory/allocation.inline.hpp" 33 #include "memory/resourceArea.hpp" 34 #include "prims/methodHandles.hpp" 35 #include "runtime/flags/flagSetting.hpp" 36 #include "runtime/frame.inline.hpp" 37 #include "utilities/preserveException.hpp" 38 39 #define __ Disassembler::hook<MacroAssembler>(__FILE__, __LINE__, _masm)-> 40 41 #ifdef PRODUCT 42 #define BLOCK_COMMENT(str) /* nothing */ 43 #define STOP(error) stop(error) 44 #else 45 #define BLOCK_COMMENT(str) __ block_comment(str) 46 #define STOP(error) block_comment(error); __ stop(error) 47 #endif 48 49 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":") 50 51 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) { 52 if (VerifyMethodHandles) 53 verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class), 54 "MH argument is a Class"); 55 __ movptr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes())); 56 } 57 58 #ifdef ASSERT 59 static int check_nonzero(const char* xname, int x) { 60 assert(x != 0, "%s should be nonzero", xname); 61 return x; 62 } 63 #define NONZERO(x) check_nonzero(#x, x) 64 #else //ASSERT 65 #define NONZERO(x) (x) 66 #endif //ASSERT 67 68 #ifdef ASSERT 69 void MethodHandles::verify_klass(MacroAssembler* _masm, 70 Register obj, SystemDictionary::WKID klass_id, 71 const char* error_message) { 72 InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id); 73 Klass* klass = SystemDictionary::well_known_klass(klass_id); 74 Register temp = rdi; 75 Register temp2 = noreg; 76 LP64_ONLY(temp2 = rscratch1); // used by MacroAssembler::cmpptr 77 Label L_ok, L_bad; 78 BLOCK_COMMENT("verify_klass {"); 79 __ verify_oop(obj); 80 __ testptr(obj, obj); 81 __ jcc(Assembler::zero, L_bad); 82 __ push(temp); if (temp2 != noreg) __ push(temp2); 83 #define UNPUSH { if (temp2 != noreg) __ pop(temp2); __ pop(temp); } 84 __ load_klass(temp, obj); 85 __ cmpptr(temp, ExternalAddress((address) klass_addr)); 86 __ jcc(Assembler::equal, L_ok); 87 intptr_t super_check_offset = klass->super_check_offset(); 88 __ movptr(temp, Address(temp, super_check_offset)); 89 __ cmpptr(temp, ExternalAddress((address) klass_addr)); 90 __ jcc(Assembler::equal, L_ok); 91 UNPUSH; 92 __ bind(L_bad); 93 __ STOP(error_message); 94 __ BIND(L_ok); 95 UNPUSH; 96 BLOCK_COMMENT("} verify_klass"); 97 } 98 99 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) { 100 Label L; 101 BLOCK_COMMENT("verify_ref_kind {"); 102 __ movl(temp, Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes()))); 103 __ shrl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT); 104 __ andl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK); 105 __ cmpl(temp, ref_kind); 106 __ jcc(Assembler::equal, L); 107 { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal); 108 jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind); 109 if (ref_kind == JVM_REF_invokeVirtual || 110 ref_kind == JVM_REF_invokeSpecial) 111 // could do this for all ref_kinds, but would explode assembly code size 112 trace_method_handle(_masm, buf); 113 __ STOP(buf); 114 } 115 BLOCK_COMMENT("} verify_ref_kind"); 116 __ bind(L); 117 } 118 119 #endif //ASSERT 120 121 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp, 122 bool for_compiler_entry) { 123 assert(method == rbx, "interpreter calling convention"); 124 125 Label L_no_such_method; 126 __ testptr(rbx, rbx); 127 __ jcc(Assembler::zero, L_no_such_method); 128 129 __ verify_method_ptr(method); 130 131 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) { 132 Label run_compiled_code; 133 // JVMTI events, such as single-stepping, are implemented partly by avoiding running 134 // compiled code in threads for which the event is enabled. Check here for 135 // interp_only_mode if these events CAN be enabled. 136 #ifdef _LP64 137 Register rthread = r15_thread; 138 #else 139 Register rthread = temp; 140 __ get_thread(rthread); 141 #endif 142 // interp_only is an int, on little endian it is sufficient to test the byte only 143 // Is a cmpl faster? 144 __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0); 145 __ jccb(Assembler::zero, run_compiled_code); 146 __ jmp(Address(method, Method::interpreter_entry_offset())); 147 __ BIND(run_compiled_code); 148 } 149 150 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() : 151 Method::from_interpreted_offset(); 152 __ jmp(Address(method, entry_offset)); 153 154 __ bind(L_no_such_method); 155 __ jump(RuntimeAddress(StubRoutines::throw_AbstractMethodError_entry())); 156 } 157 158 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm, 159 Register recv, Register method_temp, 160 Register temp2, 161 bool for_compiler_entry) { 162 BLOCK_COMMENT("jump_to_lambda_form {"); 163 // This is the initial entry point of a lazy method handle. 164 // After type checking, it picks up the invoker from the LambdaForm. 165 assert_different_registers(recv, method_temp, temp2); 166 assert(recv != noreg, "required register"); 167 assert(method_temp == rbx, "required register for loading method"); 168 169 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); }); 170 171 // Load the invoker, as MH -> MH.form -> LF.vmentry 172 __ verify_oop(recv); 173 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())), temp2); 174 __ verify_oop(method_temp); 175 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())), temp2); 176 __ verify_oop(method_temp); 177 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes())), temp2); 178 __ verify_oop(method_temp); 179 __ access_load_at(T_ADDRESS, IN_HEAP, method_temp, 180 Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes())), 181 noreg, noreg); 182 183 if (VerifyMethodHandles && !for_compiler_entry) { 184 // make sure recv is already on stack 185 __ movptr(temp2, Address(method_temp, Method::const_offset())); 186 __ load_sized_value(temp2, 187 Address(temp2, ConstMethod::size_of_parameters_offset()), 188 sizeof(u2), /*is_signed*/ false); 189 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), ""); 190 Label L; 191 __ cmpoop(recv, __ argument_address(temp2, -1)); 192 __ jcc(Assembler::equal, L); 193 __ movptr(rax, __ argument_address(temp2, -1)); 194 __ STOP("receiver not on stack"); 195 __ BIND(L); 196 } 197 198 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry); 199 BLOCK_COMMENT("} jump_to_lambda_form"); 200 } 201 202 203 // Code generation 204 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm, 205 vmIntrinsics::ID iid) { 206 const bool not_for_compiler_entry = false; // this is the interpreter entry 207 assert(is_signature_polymorphic(iid), "expected invoke iid"); 208 if (iid == vmIntrinsics::_invokeGeneric || 209 iid == vmIntrinsics::_compiledLambdaForm) { 210 // Perhaps surprisingly, the symbolic references visible to Java are not directly used. 211 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod. 212 // They all allow an appendix argument. 213 __ hlt(); // empty stubs make SG sick 214 return NULL; 215 } 216 217 // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted) 218 // rbx: Method* 219 // rdx: argument locator (parameter slot count, added to rsp) 220 // rcx: used as temp to hold mh or receiver 221 // rax, rdi: garbage temps, blown away 222 Register rdx_argp = rdx; // argument list ptr, live on error paths 223 Register rax_temp = rax; 224 Register rcx_mh = rcx; // MH receiver; dies quickly and is recycled 225 Register rbx_method = rbx; // eventual target of this invocation 226 227 // here's where control starts out: 228 __ align(CodeEntryAlignment); 229 address entry_point = __ pc(); 230 231 if (VerifyMethodHandles) { 232 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2"); 233 234 Label L; 235 BLOCK_COMMENT("verify_intrinsic_id {"); 236 __ cmpw(Address(rbx_method, Method::intrinsic_id_offset_in_bytes()), (int) iid); 237 __ jcc(Assembler::equal, L); 238 if (iid == vmIntrinsics::_linkToVirtual || 239 iid == vmIntrinsics::_linkToSpecial) { 240 // could do this for all kinds, but would explode assembly code size 241 trace_method_handle(_masm, "bad Method*::intrinsic_id"); 242 } 243 __ STOP("bad Method*::intrinsic_id"); 244 __ bind(L); 245 BLOCK_COMMENT("} verify_intrinsic_id"); 246 } 247 248 // First task: Find out how big the argument list is. 249 Address rdx_first_arg_addr; 250 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid); 251 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic"); 252 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) { 253 __ movptr(rdx_argp, Address(rbx_method, Method::const_offset())); 254 __ load_sized_value(rdx_argp, 255 Address(rdx_argp, ConstMethod::size_of_parameters_offset()), 256 sizeof(u2), /*is_signed*/ false); 257 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), ""); 258 rdx_first_arg_addr = __ argument_address(rdx_argp, -1); 259 } else { 260 DEBUG_ONLY(rdx_argp = noreg); 261 } 262 263 if (!is_signature_polymorphic_static(iid)) { 264 __ movptr(rcx_mh, rdx_first_arg_addr); 265 DEBUG_ONLY(rdx_argp = noreg); 266 } 267 268 // rdx_first_arg_addr is live! 269 270 trace_method_handle_interpreter_entry(_masm, iid); 271 272 if (iid == vmIntrinsics::_invokeBasic) { 273 generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry); 274 275 } 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 } 289 290 return entry_point; 291 } 292 293 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm, 294 vmIntrinsics::ID iid, 295 Register receiver_reg, 296 Register member_reg, 297 bool for_compiler_entry) { 298 assert(is_signature_polymorphic(iid), "expected invoke iid"); 299 Register rbx_method = rbx; // eventual target of this invocation 300 // temps used in this code are not used in *either* compiled or interpreted calling sequences 301 #ifdef _LP64 302 Register temp1 = rscratch1; 303 Register temp2 = rscratch2; 304 Register temp3 = rax; 305 if (for_compiler_entry) { 306 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment"); 307 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5); 308 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5); 309 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5); 310 } 311 #else 312 Register temp1 = (for_compiler_entry ? rsi : rdx); 313 Register temp2 = rdi; 314 Register temp3 = rax; 315 if (for_compiler_entry) { 316 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : rcx), "only valid assignment"); 317 assert_different_registers(temp1, rcx, rdx); 318 assert_different_registers(temp2, rcx, rdx); 319 assert_different_registers(temp3, rcx, rdx); 320 } 321 #endif 322 else { 323 assert_different_registers(temp1, temp2, temp3, saved_last_sp_register()); // don't trash lastSP 324 } 325 assert_different_registers(temp1, temp2, temp3, receiver_reg); 326 assert_different_registers(temp1, temp2, temp3, member_reg); 327 328 if (iid == vmIntrinsics::_invokeBasic) { 329 // indirect through MH.form.vmentry.vmtarget 330 jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry); 331 332 } else { 333 // The method is a member invoker used by direct method handles. 334 if (VerifyMethodHandles) { 335 // make sure the trailing argument really is a MemberName (caller responsibility) 336 verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_invoke_MemberName), 337 "MemberName required for invokeVirtual etc."); 338 } 339 340 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes())); 341 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes())); 342 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes())); 343 Address vmtarget_method( rbx_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes())); 344 345 Register temp1_recv_klass = temp1; 346 if (iid != vmIntrinsics::_linkToStatic) { 347 __ verify_oop(receiver_reg); 348 if (iid == vmIntrinsics::_linkToSpecial) { 349 // Don't actually load the klass; just null-check the receiver. 350 __ null_check(receiver_reg); 351 } else { 352 // load receiver klass itself 353 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes()); 354 __ load_klass(temp1_recv_klass, receiver_reg); 355 __ verify_klass_ptr(temp1_recv_klass); 356 } 357 BLOCK_COMMENT("check_receiver {"); 358 // The receiver for the MemberName must be in receiver_reg. 359 // Check the receiver against the MemberName.clazz 360 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) { 361 // Did not load it above... 362 __ load_klass(temp1_recv_klass, receiver_reg); 363 __ verify_klass_ptr(temp1_recv_klass); 364 } 365 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) { 366 Label L_ok; 367 Register temp2_defc = temp2; 368 __ load_heap_oop(temp2_defc, member_clazz, temp3); 369 load_klass_from_Class(_masm, temp2_defc); 370 __ verify_klass_ptr(temp2_defc); 371 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok); 372 // If we get here, the type check failed! 373 __ STOP("receiver class disagrees with MemberName.clazz"); 374 __ bind(L_ok); 375 } 376 BLOCK_COMMENT("} check_receiver"); 377 } 378 if (iid == vmIntrinsics::_linkToSpecial || 379 iid == vmIntrinsics::_linkToStatic) { 380 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass 381 } 382 383 // Live registers at this point: 384 // member_reg - MemberName that was the trailing argument 385 // temp1_recv_klass - klass of stacked receiver, if needed 386 // rsi/r13 - interpreter linkage (if interpreted) 387 // rcx, rdx, rsi, rdi, r8 - compiler arguments (if compiled) 388 389 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 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg); 397 break; 398 399 case vmIntrinsics::_linkToStatic: 400 if (VerifyMethodHandles) { 401 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3); 402 } 403 __ load_heap_oop(rbx_method, member_vmtarget); 404 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_method, vmtarget_method, noreg, noreg); 405 break; 406 407 case vmIntrinsics::_linkToVirtual: 408 { 409 // same as TemplateTable::invokevirtual, 410 // minus the CP setup and profiling: 411 412 if (VerifyMethodHandles) { 413 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3); 414 } 415 416 // pick out the vtable index from the MemberName, and then we can discard it: 417 Register temp2_index = temp2; 418 __ access_load_at(T_ADDRESS, IN_HEAP, temp2_index, member_vmindex, noreg, noreg); 419 420 if (VerifyMethodHandles) { 421 Label L_index_ok; 422 __ cmpl(temp2_index, 0); 423 __ jcc(Assembler::greaterEqual, L_index_ok); 424 __ STOP("no virtual index"); 425 __ BIND(L_index_ok); 426 } 427 428 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget 429 // at this point. And VerifyMethodHandles has already checked clazz, if needed. 430 431 // get target Method* & entry point 432 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method); 433 break; 434 } 435 436 case vmIntrinsics::_linkToInterface: 437 { 438 // same as TemplateTable::invokeinterface 439 // (minus the CP setup and profiling, with different argument motion) 440 if (VerifyMethodHandles) { 441 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3); 442 } 443 444 Register temp3_intf = temp3; 445 __ load_heap_oop(temp3_intf, member_clazz); 446 load_klass_from_Class(_masm, temp3_intf); 447 __ verify_klass_ptr(temp3_intf); 448 449 Register rbx_index = rbx_method; 450 __ access_load_at(T_ADDRESS, IN_HEAP, rbx_index, member_vmindex, noreg, noreg); 451 if (VerifyMethodHandles) { 452 Label L; 453 __ cmpl(rbx_index, 0); 454 __ jcc(Assembler::greaterEqual, L); 455 __ STOP("invalid vtable index for MH.invokeInterface"); 456 __ bind(L); 457 } 458 459 // given intf, index, and recv klass, dispatch to the implementation method 460 __ lookup_interface_method(temp1_recv_klass, temp3_intf, 461 // note: next two args must be the same: 462 rbx_index, rbx_method, 463 temp2, 464 L_incompatible_class_change_error); 465 break; 466 } 467 468 default: 469 fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid)); 470 break; 471 } 472 473 // Live at this point: 474 // rbx_method 475 // rsi/r13 (if interpreted) 476 477 // After figuring out which concrete method to call, jump into it. 478 // Note that this works in the interpreter with no data motion. 479 // But the compiled version will require that rcx_recv be shifted out. 480 __ verify_method_ptr(rbx_method); 481 jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry); 482 483 if (iid == vmIntrinsics::_linkToInterface) { 484 __ bind(L_incompatible_class_change_error); 485 __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry())); 486 } 487 } 488 } 489 490 #ifndef PRODUCT 491 void trace_method_handle_stub(const char* adaptername, 492 oop mh, 493 intptr_t* saved_regs, 494 intptr_t* entry_sp) { 495 // called as a leaf from native code: do not block the JVM! 496 bool has_mh = (strstr(adaptername, "/static") == NULL && 497 strstr(adaptername, "linkTo") == NULL); // static linkers don't have MH 498 const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx"; 499 tty->print_cr("MH %s %s=" PTR_FORMAT " sp=" PTR_FORMAT, 500 adaptername, mh_reg_name, 501 p2i(mh), p2i(entry_sp)); 502 503 if (Verbose) { 504 tty->print_cr("Registers:"); 505 const int saved_regs_count = RegisterImpl::number_of_registers; 506 for (int i = 0; i < saved_regs_count; i++) { 507 Register r = as_Register(i); 508 // The registers are stored in reverse order on the stack (by pusha). 509 tty->print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]); 510 if ((i + 1) % 4 == 0) { 511 tty->cr(); 512 } else { 513 tty->print(", "); 514 } 515 } 516 tty->cr(); 517 518 { 519 // dumping last frame with frame::describe 520 521 JavaThread* p = JavaThread::active(); 522 523 ResourceMark rm; 524 PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here 525 FrameValues values; 526 527 // Note: We want to allow trace_method_handle from any call site. 528 // While trace_method_handle creates a frame, it may be entered 529 // without a PC on the stack top (e.g. not just after a call). 530 // Walking that frame could lead to failures due to that invalid PC. 531 // => carefully detect that frame when doing the stack walking 532 533 // Current C frame 534 frame cur_frame = os::current_frame(); 535 536 // Robust search of trace_calling_frame (independant of inlining). 537 // Assumes saved_regs comes from a pusha in the trace_calling_frame. 538 assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?"); 539 frame trace_calling_frame = os::get_sender_for_C_frame(&cur_frame); 540 while (trace_calling_frame.fp() < saved_regs) { 541 trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame); 542 } 543 544 // safely create a frame and call frame::describe 545 intptr_t *dump_sp = trace_calling_frame.sender_sp(); 546 intptr_t *dump_fp = trace_calling_frame.link(); 547 548 bool walkable = has_mh; // whether the traced frame shoud be walkable 549 550 if (walkable) { 551 // The previous definition of walkable may have to be refined 552 // if new call sites cause the next frame constructor to start 553 // failing. Alternatively, frame constructors could be 554 // modified to support the current or future non walkable 555 // frames (but this is more intrusive and is not considered as 556 // part of this RFE, which will instead use a simpler output). 557 frame dump_frame = frame(dump_sp, dump_fp); 558 dump_frame.describe(values, 1); 559 } else { 560 // Stack may not be walkable (invalid PC above FP): 561 // Add descriptions without building a Java frame to avoid issues 562 values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>"); 563 values.describe(-1, dump_sp, "sp for #1"); 564 } 565 values.describe(-1, entry_sp, "raw top of stack"); 566 567 tty->print_cr("Stack layout:"); 568 values.print(p); 569 } 570 if (has_mh && oopDesc::is_oop(mh)) { 571 mh->print(); 572 if (java_lang_invoke_MethodHandle::is_instance(mh)) { 573 if (java_lang_invoke_MethodHandle::form_offset_in_bytes() != 0) 574 java_lang_invoke_MethodHandle::form(mh)->print(); 575 } 576 } 577 } 578 } 579 580 // The stub wraps the arguments in a struct on the stack to avoid 581 // dealing with the different calling conventions for passing 6 582 // arguments. 583 struct MethodHandleStubArguments { 584 const char* adaptername; 585 oopDesc* mh; 586 intptr_t* saved_regs; 587 intptr_t* entry_sp; 588 }; 589 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) { 590 trace_method_handle_stub(args->adaptername, 591 args->mh, 592 args->saved_regs, 593 args->entry_sp); 594 } 595 596 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) { 597 if (!TraceMethodHandles) return; 598 BLOCK_COMMENT(err_msg("trace_method_handle %s {", adaptername)); 599 __ enter(); 600 __ andptr(rsp, -16); // align stack if needed for FPU state 601 __ pusha(); 602 __ mov(rbx, rsp); // for retreiving saved_regs 603 // Note: saved_regs must be in the entered frame for the 604 // robust stack walking implemented in trace_method_handle_stub. 605 606 // save FP result, valid at some call sites (adapter_opt_return_float, ...) 607 __ increment(rsp, -2 * wordSize); 608 if (UseSSE >= 2) { 609 __ movdbl(Address(rsp, 0), xmm0); 610 } else if (UseSSE == 1) { 611 __ movflt(Address(rsp, 0), xmm0); 612 } else { 613 __ fst_d(Address(rsp, 0)); 614 } 615 616 // Incoming state: 617 // rcx: method handle 618 // 619 // To avoid calling convention issues, build a record on the stack 620 // and pass the pointer to that instead. 621 __ push(rbp); // entry_sp (with extra align space) 622 __ push(rbx); // pusha saved_regs 623 __ push(rcx); // mh 624 __ push(rcx); // slot for adaptername 625 __ movptr(Address(rsp, 0), (intptr_t) adaptername); 626 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp); 627 __ increment(rsp, sizeof(MethodHandleStubArguments)); 628 629 if (UseSSE >= 2) { 630 __ movdbl(xmm0, Address(rsp, 0)); 631 } else if (UseSSE == 1) { 632 __ movflt(xmm0, Address(rsp, 0)); 633 } else { 634 __ fld_d(Address(rsp, 0)); 635 } 636 __ increment(rsp, 2 * wordSize); 637 638 __ popa(); 639 __ leave(); 640 BLOCK_COMMENT("} trace_method_handle"); 641 } 642 #endif //PRODUCT