1 /*
   2  * Copyright (c) 2008, 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 "jvm.h"
  27 #include "asm/macroAssembler.hpp"
  28 #include "classfile/javaClasses.inline.hpp"
  29 #include "interpreter/interpreter.hpp"
  30 #include "interpreter/interp_masm.hpp"
  31 #include "memory/allocation.inline.hpp"
  32 #include "memory/resourceArea.hpp"
  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 // Workaround for C++ overloading nastiness on '0' for RegisterOrConstant.
  48 static RegisterOrConstant constant(int value) {
  49   return RegisterOrConstant(value);
  50 }
  51 
  52 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg, Register temp_reg, Register temp2_reg) {
  53   if (VerifyMethodHandles)
  54     verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class), temp_reg, temp2_reg,
  55                  "MH argument is a Class");
  56   __ ld_ptr(Address(klass_reg, java_lang_Class::klass_offset_in_bytes()), klass_reg);
  57 }
  58 
  59 #ifdef ASSERT
  60 static int check_nonzero(const char* xname, int x) {
  61   assert(x != 0, "%s should be nonzero", xname);
  62   return x;
  63 }
  64 #define NONZERO(x) check_nonzero(#x, x)
  65 #else //ASSERT
  66 #define NONZERO(x) (x)
  67 #endif //ASSERT
  68 
  69 #ifdef ASSERT
  70 void MethodHandles::verify_klass(MacroAssembler* _masm,
  71                                  Register obj_reg, SystemDictionary::WKID klass_id,
  72                                  Register temp_reg, Register temp2_reg,
  73                                  const char* error_message) {
  74   InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id);
  75   Klass* klass = SystemDictionary::well_known_klass(klass_id);
  76   bool did_save = false;
  77   if (temp_reg == noreg || temp2_reg == noreg) {
  78     temp_reg = L1;
  79     temp2_reg = L2;
  80     __ save_frame_and_mov(0, obj_reg, L0);
  81     obj_reg = L0;
  82     did_save = true;
  83   }
  84   Label L_ok, L_bad;
  85   BLOCK_COMMENT("verify_klass {");
  86   __ verify_oop(obj_reg);
  87   __ br_null_short(obj_reg, Assembler::pn, L_bad);
  88   __ load_klass(obj_reg, temp_reg);
  89   __ set(ExternalAddress((Metadata**)klass_addr), temp2_reg);
  90   __ ld_ptr(Address(temp2_reg, 0), temp2_reg);
  91   __ cmp_and_brx_short(temp_reg, temp2_reg, Assembler::equal, Assembler::pt, L_ok);
  92   intptr_t super_check_offset = klass->super_check_offset();
  93   __ ld_ptr(Address(temp_reg, super_check_offset), temp_reg);
  94   __ set(ExternalAddress((Metadata**)klass_addr), temp2_reg);
  95   __ ld_ptr(Address(temp2_reg, 0), temp2_reg);
  96   __ cmp_and_brx_short(temp_reg, temp2_reg, Assembler::equal, Assembler::pt, L_ok);
  97   __ BIND(L_bad);
  98   if (did_save)  __ restore();
  99   __ STOP(error_message);
 100   __ BIND(L_ok);
 101   if (did_save)  __ restore();
 102   BLOCK_COMMENT("} verify_klass");
 103 }
 104 
 105 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {
 106   Label L;
 107   BLOCK_COMMENT("verify_ref_kind {");
 108   __ lduw(Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes())), temp);
 109   __ srl( temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT, temp);
 110   __ and3(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK,  temp);
 111   __ cmp_and_br_short(temp, ref_kind, Assembler::equal, Assembler::pt, L);
 112   { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);
 113     jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);
 114     if (ref_kind == JVM_REF_invokeVirtual ||
 115         ref_kind == JVM_REF_invokeSpecial)
 116       // could do this for all ref_kinds, but would explode assembly code size
 117       trace_method_handle(_masm, buf);
 118     __ STOP(buf);
 119   }
 120   BLOCK_COMMENT("} verify_ref_kind");
 121   __ bind(L);
 122 }
 123 
 124 #endif // ASSERT
 125 
 126 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register target, Register temp,
 127                                             bool for_compiler_entry) {
 128   Label L_no_such_method;
 129   assert(method == G5_method, "interpreter calling convention");
 130   assert_different_registers(method, target, temp);
 131 
 132   if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
 133     Label run_compiled_code;
 134     // JVMTI events, such as single-stepping, are implemented partly by avoiding running
 135     // compiled code in threads for which the event is enabled.  Check here for
 136     // interp_only_mode if these events CAN be enabled.
 137     __ verify_thread();
 138     const Address interp_only(G2_thread, JavaThread::interp_only_mode_offset());
 139     __ ld(interp_only, temp);
 140     __ cmp_and_br_short(temp, 0, Assembler::zero, Assembler::pt, run_compiled_code);
 141     // Null method test is replicated below in compiled case,
 142     // it might be able to address across the verify_thread()
 143     __ br_null_short(G5_method, Assembler::pn, L_no_such_method);
 144     __ ld_ptr(G5_method, in_bytes(Method::interpreter_entry_offset()), target);
 145     __ jmp(target, 0);
 146     __ delayed()->nop();
 147     __ BIND(run_compiled_code);
 148     // Note: we could fill some delay slots here, but
 149     // it doesn't matter, since this is interpreter code.
 150   }
 151 
 152   // Compiled case, either static or fall-through from runtime conditional
 153   __ br_null_short(G5_method, Assembler::pn, L_no_such_method);
 154 
 155   const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
 156                                                      Method::from_interpreted_offset();
 157   __ ld_ptr(G5_method, in_bytes(entry_offset), target);
 158   __ jmp(target, 0);
 159   __ delayed()->nop();
 160 
 161   __ bind(L_no_such_method);
 162   AddressLiteral ame(StubRoutines::throw_AbstractMethodError_entry());
 163   __ jump_to(ame, temp);
 164   __ delayed()->nop();
 165 }
 166 
 167 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
 168                                         Register recv, Register method_temp,
 169                                         Register temp2, Register temp3,
 170                                         bool for_compiler_entry) {
 171   BLOCK_COMMENT("jump_to_lambda_form {");
 172   // This is the initial entry point of a lazy method handle.
 173   // After type checking, it picks up the invoker from the LambdaForm.
 174   assert_different_registers(recv, method_temp, temp2);  // temp3 is only passed on
 175   assert(method_temp == G5_method, "required register for loading method");
 176 
 177   //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); });
 178 
 179   // Load the invoker, as MH -> MH.form -> LF.vmentry
 180   __ verify_oop(recv);
 181   __ load_heap_oop(Address(recv,        NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())),   method_temp);
 182   __ verify_oop(method_temp);
 183   __ load_heap_oop(Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())),  method_temp);
 184   __ verify_oop(method_temp);
 185   __ load_heap_oop(Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes())), method_temp);
 186   __ verify_oop(method_temp);
 187   __ ld_ptr(       Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes())),   method_temp);
 188 
 189   if (VerifyMethodHandles && !for_compiler_entry) {
 190     // make sure recv is already on stack
 191     __ ld_ptr(method_temp, in_bytes(Method::const_offset()), temp2);
 192     __ load_sized_value(Address(temp2, ConstMethod::size_of_parameters_offset()),
 193                         temp2,
 194                         sizeof(u2), /*is_signed*/ false);
 195     // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
 196     Label L;
 197     __ ld_ptr(__ argument_address(temp2, temp2, -1), temp2);
 198     __ cmp_and_br_short(temp2, recv, Assembler::equal, Assembler::pt, L);
 199     __ STOP("receiver not on stack");
 200     __ BIND(L);
 201   }
 202 
 203   jump_from_method_handle(_masm, method_temp, temp2, temp3, for_compiler_entry);
 204   BLOCK_COMMENT("} jump_to_lambda_form");
 205 }
 206 
 207 
 208 // Code generation
 209 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
 210                                                                 vmIntrinsics::ID iid) {
 211   const bool not_for_compiler_entry = false;  // this is the interpreter entry
 212   assert(is_signature_polymorphic(iid), "expected invoke iid");
 213   if (iid == vmIntrinsics::_invokeGeneric ||
 214       iid == vmIntrinsics::_compiledLambdaForm) {
 215     // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
 216     // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
 217     // They all allow an appendix argument.
 218     __ should_not_reach_here();           // empty stubs make SG sick
 219     return NULL;
 220   }
 221 
 222   // I5_savedSP/O5_savedSP: sender SP (must preserve; see prepare_to_jump_from_interpreted)
 223   // G5_method:  Method*
 224   // G4 (Gargs): incoming argument list (must preserve)
 225   // O0: used as temp to hold mh or receiver
 226   // O1, O4: garbage temps, blown away
 227   Register O1_scratch    = O1;
 228   Register O4_param_size = O4;   // size of parameters
 229 
 230   // here's where control starts out:
 231   __ align(CodeEntryAlignment);
 232   address entry_point = __ pc();
 233 
 234   if (VerifyMethodHandles) {
 235     assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
 236 
 237     Label L;
 238     BLOCK_COMMENT("verify_intrinsic_id {");
 239     __ lduh(Address(G5_method, Method::intrinsic_id_offset_in_bytes()), O1_scratch);
 240     __ cmp_and_br_short(O1_scratch, (int) iid, Assembler::equal, Assembler::pt, L);
 241     if (iid == vmIntrinsics::_linkToVirtual ||
 242         iid == vmIntrinsics::_linkToSpecial) {
 243       // could do this for all kinds, but would explode assembly code size
 244       trace_method_handle(_masm, "bad Method*::intrinsic_id");
 245     }
 246     __ STOP("bad Method*::intrinsic_id");
 247     __ bind(L);
 248     BLOCK_COMMENT("} verify_intrinsic_id");
 249   }
 250 
 251   // First task:  Find out how big the argument list is.
 252   Address O4_first_arg_addr;
 253   int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
 254   assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
 255   if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
 256     __ ld_ptr(G5_method, in_bytes(Method::const_offset()), O4_param_size);
 257     __ load_sized_value(Address(O4_param_size, ConstMethod::size_of_parameters_offset()),
 258                         O4_param_size,
 259                         sizeof(u2), /*is_signed*/ false);
 260     // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
 261     O4_first_arg_addr = __ argument_address(O4_param_size, O4_param_size, -1);
 262   } else {
 263     DEBUG_ONLY(O4_param_size = noreg);
 264   }
 265 
 266   Register O0_mh = noreg;
 267   if (!is_signature_polymorphic_static(iid)) {
 268     __ ld_ptr(O4_first_arg_addr, O0_mh = O0);
 269     DEBUG_ONLY(O4_param_size = noreg);
 270   }
 271 
 272   // O4_first_arg_addr is live!
 273 
 274   if (TraceMethodHandles) {
 275     if (O0_mh != noreg)
 276       __ mov(O0_mh, G3_method_handle);  // make stub happy
 277     trace_method_handle_interpreter_entry(_masm, iid);
 278   }
 279 
 280   if (iid == vmIntrinsics::_invokeBasic) {
 281     generate_method_handle_dispatch(_masm, iid, O0_mh, noreg, not_for_compiler_entry);
 282 
 283   } else {
 284     // Adjust argument list by popping the trailing MemberName argument.
 285     Register O0_recv = noreg;
 286     if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
 287       // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
 288       __ ld_ptr(O4_first_arg_addr, O0_recv = O0);
 289       DEBUG_ONLY(O4_param_size = noreg);
 290     }
 291     Register G5_member = G5_method;  // MemberName ptr; incoming method ptr is dead now
 292     __ ld_ptr(__ argument_address(constant(0)), G5_member);
 293     __ add(Gargs, Interpreter::stackElementSize, Gargs);
 294     generate_method_handle_dispatch(_masm, iid, O0_recv, G5_member, not_for_compiler_entry);
 295   }
 296 
 297   return entry_point;
 298 }
 299 
 300 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
 301                                                     vmIntrinsics::ID iid,
 302                                                     Register receiver_reg,
 303                                                     Register member_reg,
 304                                                     bool for_compiler_entry) {
 305   assert(is_signature_polymorphic(iid), "expected invoke iid");
 306   Register temp1 = (for_compiler_entry ? G1_scratch : O1);
 307   Register temp2 = (for_compiler_entry ? G3_scratch : O2);
 308   Register temp3 = (for_compiler_entry ? G4_scratch : O3);
 309   Register temp4 = (for_compiler_entry ? noreg      : O4);
 310   if (for_compiler_entry) {
 311     assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : O0), "only valid assignment");
 312     assert_different_registers(temp1, O0, O1, O2, O3, O4, O5);
 313     assert_different_registers(temp2, O0, O1, O2, O3, O4, O5);
 314     assert_different_registers(temp3, O0, O1, O2, O3, O4, O5);
 315     assert_different_registers(temp4, O0, O1, O2, O3, O4, O5);
 316   } else {
 317     assert_different_registers(temp1, temp2, temp3, temp4, O5_savedSP);  // don't trash lastSP
 318   }
 319   if (receiver_reg != noreg)  assert_different_registers(temp1, temp2, temp3, temp4, receiver_reg);
 320   if (member_reg   != noreg)  assert_different_registers(temp1, temp2, temp3, temp4, member_reg);
 321 
 322   if (iid == vmIntrinsics::_invokeBasic) {
 323     // indirect through MH.form.vmentry.vmtarget
 324     jump_to_lambda_form(_masm, receiver_reg, G5_method, temp1, temp2, for_compiler_entry);
 325 
 326   } else {
 327     // The method is a member invoker used by direct method handles.
 328     if (VerifyMethodHandles) {
 329       // make sure the trailing argument really is a MemberName (caller responsibility)
 330       verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(MemberName_klass),
 331                    temp1, temp2,
 332                    "MemberName required for invokeVirtual etc.");
 333     }
 334 
 335     Address member_clazz(    member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()));
 336     Address member_vmindex(  member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()));
 337     Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()));
 338     Address vmtarget_method( G5_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes()));
 339 
 340     Register temp1_recv_klass = temp1;
 341     if (iid != vmIntrinsics::_linkToStatic) {
 342       __ verify_oop(receiver_reg);
 343       if (iid == vmIntrinsics::_linkToSpecial) {
 344         // Don't actually load the klass; just null-check the receiver.
 345         __ null_check(receiver_reg);
 346       } else {
 347         // load receiver klass itself
 348         __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes());
 349         __ load_klass(receiver_reg, temp1_recv_klass);
 350         __ verify_klass_ptr(temp1_recv_klass);
 351       }
 352       BLOCK_COMMENT("check_receiver {");
 353       // The receiver for the MemberName must be in receiver_reg.
 354       // Check the receiver against the MemberName.clazz
 355       if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
 356         // Did not load it above...
 357         __ load_klass(receiver_reg, temp1_recv_klass);
 358         __ verify_klass_ptr(temp1_recv_klass);
 359       }
 360       if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
 361         Label L_ok;
 362         Register temp2_defc = temp2;
 363         __ load_heap_oop(member_clazz, temp2_defc);
 364         load_klass_from_Class(_masm, temp2_defc, temp3, temp4);
 365         __ verify_klass_ptr(temp2_defc);
 366         __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, temp4, L_ok);
 367         // If we get here, the type check failed!
 368         __ STOP("receiver class disagrees with MemberName.clazz");
 369         __ bind(L_ok);
 370       }
 371       BLOCK_COMMENT("} check_receiver");
 372     }
 373     if (iid == vmIntrinsics::_linkToSpecial ||
 374         iid == vmIntrinsics::_linkToStatic) {
 375       DEBUG_ONLY(temp1_recv_klass = noreg);  // these guys didn't load the recv_klass
 376     }
 377 
 378     // Live registers at this point:
 379     //  member_reg - MemberName that was the trailing argument
 380     //  temp1_recv_klass - klass of stacked receiver, if needed
 381     //  O5_savedSP - interpreter linkage (if interpreted)
 382     //  O0..O5 - compiler arguments (if compiled)
 383 
 384     Label L_incompatible_class_change_error;
 385     switch (iid) {
 386     case vmIntrinsics::_linkToSpecial:
 387       if (VerifyMethodHandles) {
 388         verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp2);
 389       }
 390       __ load_heap_oop(member_vmtarget, G5_method);
 391       __ ld_ptr(vmtarget_method, G5_method);
 392       break;
 393 
 394     case vmIntrinsics::_linkToStatic:
 395       if (VerifyMethodHandles) {
 396         verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp2);
 397       }
 398       __ load_heap_oop(member_vmtarget, G5_method);
 399       __ ld_ptr(vmtarget_method, G5_method);
 400       break;
 401 
 402     case vmIntrinsics::_linkToVirtual:
 403     {
 404       // same as TemplateTable::invokevirtual,
 405       // minus the CP setup and profiling:
 406 
 407       if (VerifyMethodHandles) {
 408         verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp2);
 409       }
 410 
 411       // pick out the vtable index from the MemberName, and then we can discard it:
 412       Register temp2_index = temp2;
 413       __ ld_ptr(member_vmindex, temp2_index);
 414 
 415       if (VerifyMethodHandles) {
 416         Label L_index_ok;
 417         __ cmp_and_br_short(temp2_index, (int) 0, Assembler::greaterEqual, Assembler::pn, L_index_ok);
 418         __ STOP("no virtual index");
 419         __ BIND(L_index_ok);
 420       }
 421 
 422       // Note:  The verifier invariants allow us to ignore MemberName.clazz and vmtarget
 423       // at this point.  And VerifyMethodHandles has already checked clazz, if needed.
 424 
 425       // get target Method* & entry point
 426       __ lookup_virtual_method(temp1_recv_klass, temp2_index, G5_method);
 427       break;
 428     }
 429 
 430     case vmIntrinsics::_linkToInterface:
 431     {
 432       // same as TemplateTable::invokeinterface
 433       // (minus the CP setup and profiling, with different argument motion)
 434       if (VerifyMethodHandles) {
 435         verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp2);
 436       }
 437 
 438       Register temp2_intf = temp2;
 439       __ load_heap_oop(member_clazz, temp2_intf);
 440       load_klass_from_Class(_masm, temp2_intf, temp3, temp4);
 441       __ verify_klass_ptr(temp2_intf);
 442 
 443       Register G5_index = G5_method;
 444       __ ld_ptr(member_vmindex, G5_index);
 445       if (VerifyMethodHandles) {
 446         Label L;
 447         __ cmp_and_br_short(G5_index, 0, Assembler::greaterEqual, Assembler::pt, L);
 448         __ STOP("invalid vtable index for MH.invokeInterface");
 449         __ bind(L);
 450       }
 451 
 452       // given intf, index, and recv klass, dispatch to the implementation method
 453       __ lookup_interface_method(temp1_recv_klass, temp2_intf,
 454                                  // note: next two args must be the same:
 455                                  G5_index, G5_method,
 456                                  temp3, temp4,
 457                                  L_incompatible_class_change_error);
 458       break;
 459     }
 460 
 461     default:
 462       fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid));
 463       break;
 464     }
 465 
 466     // Live at this point:
 467     //   G5_method
 468     //   O5_savedSP (if interpreted)
 469 
 470     // After figuring out which concrete method to call, jump into it.
 471     // Note that this works in the interpreter with no data motion.
 472     // But the compiled version will require that rcx_recv be shifted out.
 473     __ verify_method_ptr(G5_method);
 474     jump_from_method_handle(_masm, G5_method, temp1, temp2, for_compiler_entry);
 475 
 476     if (iid == vmIntrinsics::_linkToInterface) {
 477       __ BIND(L_incompatible_class_change_error);
 478       AddressLiteral icce(StubRoutines::throw_IncompatibleClassChangeError_entry());
 479       __ jump_to(icce, temp1);
 480       __ delayed()->nop();
 481     }
 482   }
 483 }
 484 
 485 #ifndef PRODUCT
 486 void trace_method_handle_stub(const char* adaptername,
 487                               oopDesc* mh,
 488                               intptr_t* saved_sp,
 489                               intptr_t* args,
 490                               intptr_t* tracing_fp) {
 491   bool has_mh = (strstr(adaptername, "/static") == NULL &&
 492                  strstr(adaptername, "linkTo") == NULL);    // static linkers don't have MH
 493   const char* mh_reg_name = has_mh ? "G3_mh" : "G3";
 494   tty->print_cr("MH %s %s=" INTPTR_FORMAT " saved_sp=" INTPTR_FORMAT " args=" INTPTR_FORMAT,
 495                 adaptername, mh_reg_name,
 496                 p2i(mh), p2i(saved_sp), p2i(args));
 497 
 498   if (Verbose) {
 499     // dumping last frame with frame::describe
 500 
 501     JavaThread* p = JavaThread::active();
 502 
 503     ResourceMark rm;
 504     PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here
 505     FrameValues values;
 506 
 507     // Note: We want to allow trace_method_handle from any call site.
 508     // While trace_method_handle creates a frame, it may be entered
 509     // without a valid return PC in O7 (e.g. not just after a call).
 510     // Walking that frame could lead to failures due to that invalid PC.
 511     // => carefully detect that frame when doing the stack walking
 512 
 513     // walk up to the right frame using the "tracing_fp" argument
 514     intptr_t* cur_sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
 515     frame cur_frame(cur_sp, frame::unpatchable, NULL);
 516 
 517     while (cur_frame.fp() != (intptr_t *)(STACK_BIAS+(uintptr_t)tracing_fp)) {
 518       cur_frame = os::get_sender_for_C_frame(&cur_frame);
 519     }
 520 
 521     // safely create a frame and call frame::describe
 522     intptr_t *dump_sp = cur_frame.sender_sp();
 523     intptr_t *dump_fp = cur_frame.link();
 524 
 525     bool walkable = has_mh; // whether the traced frame shoud be walkable
 526 
 527     // the sender for cur_frame is the caller of trace_method_handle
 528     if (walkable) {
 529       // The previous definition of walkable may have to be refined
 530       // if new call sites cause the next frame constructor to start
 531       // failing. Alternatively, frame constructors could be
 532       // modified to support the current or future non walkable
 533       // frames (but this is more intrusive and is not considered as
 534       // part of this RFE, which will instead use a simpler output).
 535       frame dump_frame = frame(dump_sp,
 536                                cur_frame.sp(), // younger_sp
 537                                false); // no adaptation
 538       dump_frame.describe(values, 1);
 539     } else {
 540       // Robust dump for frames which cannot be constructed from sp/younger_sp
 541       // Add descriptions without building a Java frame to avoid issues
 542       values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
 543       values.describe(-1, dump_sp, "sp");
 544     }
 545 
 546     bool has_args = has_mh; // whether Gargs is meaningful
 547 
 548     // mark args, if seems valid (may not be valid for some adapters)
 549     if (has_args) {
 550       if ((args >= dump_sp) && (args < dump_fp)) {
 551         values.describe(-1, args, "*G4_args");
 552       }
 553     }
 554 
 555     // mark saved_sp, if seems valid (may not be valid for some adapters)
 556     intptr_t *unbiased_sp = (intptr_t *)(STACK_BIAS+(uintptr_t)saved_sp);
 557     const int ARG_LIMIT = 255, SLOP = 45, UNREASONABLE_STACK_MOVE = (ARG_LIMIT + SLOP);
 558     if ((unbiased_sp >= dump_sp - UNREASONABLE_STACK_MOVE) && (unbiased_sp < dump_fp)) {
 559       values.describe(-1, unbiased_sp, "*saved_sp+STACK_BIAS");
 560     }
 561 
 562     // Note: the unextended_sp may not be correct
 563     tty->print_cr("  stack layout:");
 564     values.print(p);
 565     if (has_mh && oopDesc::is_oop(mh)) {
 566       mh->print();
 567       if (java_lang_invoke_MethodHandle::is_instance(mh)) {
 568         if (java_lang_invoke_MethodHandle::form_offset_in_bytes() != 0)
 569           java_lang_invoke_MethodHandle::form(mh)->print();
 570       }
 571     }
 572   }
 573 }
 574 
 575 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
 576   if (!TraceMethodHandles)  return;
 577   BLOCK_COMMENT("trace_method_handle {");
 578   // save: Gargs, O5_savedSP
 579   __ save_frame(16); // need space for saving required FPU state
 580 
 581   __ set((intptr_t) adaptername, O0);
 582   __ mov(G3_method_handle, O1);
 583   __ mov(I5_savedSP, O2);
 584   __ mov(Gargs, O3);
 585   __ mov(I6, O4); // frame identifier for safe stack walking
 586 
 587   // Save scratched registers that might be needed. Robustness is more
 588   // important than optimizing the saves for this debug only code.
 589 
 590   // save FP result, valid at some call sites (adapter_opt_return_float, ...)
 591   Address d_save(FP, -sizeof(jdouble) + STACK_BIAS);
 592   __ stf(FloatRegisterImpl::D, Ftos_d, d_save);
 593   // Safely save all globals but G2 (handled by call_VM_leaf) and G7
 594   // (OS reserved).
 595   __ mov(G3_method_handle, L3);
 596   __ mov(Gargs, L4);
 597   __ mov(G5_method_type, L5);
 598   __ mov(G6, L6);
 599   __ mov(G1, L1);
 600 
 601   __ call_VM_leaf(L2 /* for G2 */, CAST_FROM_FN_PTR(address, trace_method_handle_stub));
 602 
 603   __ mov(L3, G3_method_handle);
 604   __ mov(L4, Gargs);
 605   __ mov(L5, G5_method_type);
 606   __ mov(L6, G6);
 607   __ mov(L1, G1);
 608   __ ldf(FloatRegisterImpl::D, d_save, Ftos_d);
 609 
 610   __ restore();
 611   BLOCK_COMMENT("} trace_method_handle");
 612 }
 613 #endif // PRODUCT
--- EOF ---