methodHandles_x86.cpp revision 3602:da91efe96a93
113546Sjulian/* 235509Sjb * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved. 313546Sjulian * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 413546Sjulian * 513546Sjulian * This code is free software; you can redistribute it and/or modify it 613546Sjulian * under the terms of the GNU General Public License version 2 only, as 713546Sjulian * published by the Free Software Foundation. 813546Sjulian * 913546Sjulian * This code is distributed in the hope that it will be useful, but WITHOUT 1013546Sjulian * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1113546Sjulian * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 1213546Sjulian * version 2 for more details (a copy is included in the LICENSE file that 13165967Simp * accompanied this code). 1413546Sjulian * 1513546Sjulian * You should have received a copy of the GNU General Public License version 1613546Sjulian * 2 along with this work; if not, write to the Free Software Foundation, 1713546Sjulian * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 1813546Sjulian * 1913546Sjulian * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2049439Sdeischen * or visit www.oracle.com if you need additional information or have any 2113546Sjulian * questions. 2213546Sjulian * 2313546Sjulian */ 2413546Sjulian 2513546Sjulian#include "precompiled.hpp" 2613546Sjulian#include "interpreter/interpreter.hpp" 2713546Sjulian#include "interpreter/interpreterRuntime.hpp" 2813546Sjulian#include "memory/allocation.inline.hpp" 2950476Speter#include "prims/methodHandles.hpp" 3024518Sjb 3113546Sjulian#define __ _masm-> 3213546Sjulian 3313546Sjulian#ifdef PRODUCT 3413546Sjulian#define BLOCK_COMMENT(str) /* nothing */ 3513546Sjulian#define STOP(error) stop(error) 3636830Sjb#else 3736830Sjb#define BLOCK_COMMENT(str) __ block_comment(str) 3813546Sjulian#define STOP(error) block_comment(error); __ stop(error) 3913546Sjulian#endif 40103388Smini 4113546Sjulian#define BIND(label) bind(label); BLOCK_COMMENT(#label ":") 42174112Sdeischen 43174112Sdeischen// Workaround for C++ overloading nastiness on '0' for RegisterOrConstant. 4495948Sarchiestatic RegisterOrConstant constant(int value) { 4571581Sdeischen return RegisterOrConstant(value); 4613546Sjulian} 4795948Sarchie 4895948Sarchievoid MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) { 49113658Sdeischen if (VerifyMethodHandles) 5095948Sarchie verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class), 5195948Sarchie "MH argument is a Class"); 52123312Sdavidxu __ movptr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes())); 53103419Smini} 54123312Sdavidxu 5595948Sarchie#ifdef ASSERT 5695948Sarchiestatic int check_nonzero(const char* xname, int x) { 5795948Sarchie 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 64 65#ifdef ASSERT 66void 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} 95 96void 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} 115 116#endif //ASSERT 117 118void 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); 122 123 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 } 141 142 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() : 143 Method::from_interpreted_offset(); 144 __ jmp(Address(method, entry_offset)); 145} 146 147void 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"); 157 158 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); }); 159 160 // 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()))); 168 169 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 } 182 183 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry); 184 BLOCK_COMMENT("} jump_to_lambda_form"); 185} 186 187 188// Code generation 189address 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 } 201 202 // 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 211 212 address code_start = __ pc(); 213 214 // here's where control starts out: 215 __ align(CodeEntryAlignment); 216 address entry_point = __ pc(); 217 218 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 } 232 233 // 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 } 246 247 if (!is_signature_polymorphic_static(iid)) { 248 __ movptr(rcx_mh, rdx_first_arg_addr); 249 DEBUG_ONLY(rdx_argp = noreg); 250 } 251 252 // rdx_first_arg_addr is live! 253 254 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 } 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 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 } 297 298 return entry_point; 299} 300 301void 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 334 335 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); 338 339 } 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 } 346 347 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())); 350 351 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 } 388 389 // 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) 394 395 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; 404 405 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; 412 413 case vmIntrinsics::_linkToVirtual: 414 { 415 // same as TemplateTable::invokevirtual, 416 // minus the CP setup and profiling: 417 418 if (VerifyMethodHandles) { 419 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3); 420 } 421 422 // 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); 425 426 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 } 433 434 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget 435 // at this point. And VerifyMethodHandles has already checked clazz, if needed. 436 437 // get target Method* & entry point 438 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method); 439 method_is_live = true; 440 break; 441 } 442 443 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 } 450 451 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); 455 456 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 } 465 466 // 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); 473 474 __ verify_oop(rbx_method); 475 jump_from_method_handle(_masm, rbx_method, temp2, for_compiler_entry); 476 __ hlt(); 477 478 __ bind(L_no_such_interface); 479 __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry())); 480 break; 481 } 482 483 default: 484 fatal(err_msg("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid))); 485 break; 486 } 487 488 if (method_is_live) { 489 // live at this point: rbx_method, rsi/r13 (if interpreted) 490 491 // 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} 499 500#ifndef PRODUCT 501void 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); 512 513 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(); 527 528 { 529 // dumping last frame with frame::describe 530 531 JavaThread* p = JavaThread::active(); 532 533 ResourceMark rm; 534 PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here 535 FrameValues values; 536 537 // 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 542 543 // Current C frame 544 frame cur_frame = os::current_frame(); 545 546 // 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 } 553 554 // 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(); 557 558 bool walkable = has_mh; // whether the traced frame shoud be walkable 559 560 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"); 576 577 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} 589 590// 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. 593struct MethodHandleStubArguments { 594 const char* adaptername; 595 oopDesc* mh; 596 intptr_t* saved_regs; 597 intptr_t* entry_sp; 598}; 599void 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} 605 606void 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. 615 616 // 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 } 625 626 // 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)); 638 639 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); 647 648 __ popa(); 649 __ leave(); 650 BLOCK_COMMENT("} trace_method_handle"); 651} 652#endif //PRODUCT 653