1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2012, 2017 SAP SE. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #include "precompiled.hpp"
  27 #include "jvm.h"
  28 #include "asm/macroAssembler.inline.hpp"
  29 #include "classfile/javaClasses.inline.hpp"
  30 #include "interpreter/interpreter.hpp"
  31 #include "memory/allocation.inline.hpp"
  32 #include "memory/resourceArea.hpp"
  33 #include "prims/methodHandles.hpp"
  34 #include "utilities/preserveException.hpp"
  35 
  36 #define __ _masm->
  37 
  38 #ifdef PRODUCT
  39 #define BLOCK_COMMENT(str) // nothing
  40 #else
  41 #define BLOCK_COMMENT(str) __ block_comment(str)
  42 #endif
  43 
  44 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
  45 
  46 // Workaround for C++ overloading nastiness on '0' for RegisterOrConstant.
  47 inline static RegisterOrConstant constant(int value) {
  48   return RegisterOrConstant(value);
  49 }
  50 
  51 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg,
  52                                           Register temp_reg, Register temp2_reg) {
  53   if (VerifyMethodHandles) {
  54     verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class),
  55                  temp_reg, temp2_reg, "MH argument is a Class");
  56   }
  57   __ ld(klass_reg, java_lang_Class::klass_offset_in_bytes(), klass_reg);
  58 }
  59 
  60 #ifdef ASSERT
  61 static int check_nonzero(const char* xname, int x) {
  62   assert(x != 0, "%s should be nonzero", xname);
  63   return x;
  64 }
  65 #define NONZERO(x) check_nonzero(#x, x)
  66 #else //ASSERT
  67 #define NONZERO(x) (x)
  68 #endif //ASSERT
  69 
  70 #ifdef ASSERT
  71 void MethodHandles::verify_klass(MacroAssembler* _masm,
  72                                  Register obj_reg, SystemDictionary::WKID klass_id,
  73                                  Register temp_reg, Register temp2_reg,
  74                                  const char* error_message) {
  75   InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id);
  76   Klass* klass = SystemDictionary::well_known_klass(klass_id);
  77   Label L_ok, L_bad;
  78   BLOCK_COMMENT("verify_klass {");
  79   __ verify_oop(obj_reg);
  80   __ cmpdi(CCR0, obj_reg, 0);
  81   __ beq(CCR0, L_bad);
  82   __ load_klass(temp_reg, obj_reg);
  83   __ load_const_optimized(temp2_reg, (address) klass_addr);
  84   __ ld(temp2_reg, 0, temp2_reg);
  85   __ cmpd(CCR0, temp_reg, temp2_reg);
  86   __ beq(CCR0, L_ok);
  87   __ ld(temp_reg, klass->super_check_offset(), temp_reg);
  88   __ cmpd(CCR0, temp_reg, temp2_reg);
  89   __ beq(CCR0, L_ok);
  90   __ BIND(L_bad);
  91   __ stop(error_message);
  92   __ BIND(L_ok);
  93   BLOCK_COMMENT("} verify_klass");
  94 }
  95 
  96 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {
  97   Label L;
  98   BLOCK_COMMENT("verify_ref_kind {");
  99   __ load_sized_value(temp, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes()), member_reg,
 100                       sizeof(u4), /*is_signed*/ false);
 101   // assert(sizeof(u4) == sizeof(java.lang.invoke.MemberName.flags), "");
 102   __ srwi( temp, temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT);
 103   __ andi(temp, temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK);
 104   __ cmpwi(CCR1, temp, ref_kind);
 105   __ beq(CCR1, L);
 106   { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);
 107     jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);
 108     if (ref_kind == JVM_REF_invokeVirtual ||
 109         ref_kind == JVM_REF_invokeSpecial)
 110       // could do this for all ref_kinds, but would explode assembly code size
 111       trace_method_handle(_masm, buf);
 112     __ stop(buf);
 113   }
 114   BLOCK_COMMENT("} verify_ref_kind");
 115   __ BIND(L);
 116 }
 117 
 118 #endif // ASSERT
 119 
 120 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register target, Register temp,
 121                                             bool for_compiler_entry) {
 122   Label L_no_such_method;
 123   assert(method == R19_method, "interpreter calling convention");
 124   assert_different_registers(method, target, temp);
 125 
 126   if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
 127     Label run_compiled_code;
 128     // JVMTI events, such as single-stepping, are implemented partly by avoiding running
 129     // compiled code in threads for which the event is enabled.  Check here for
 130     // interp_only_mode if these events CAN be enabled.
 131     __ verify_thread();
 132     __ lwz(temp, in_bytes(JavaThread::interp_only_mode_offset()), R16_thread);
 133     __ cmplwi(CCR0, temp, 0);
 134     __ beq(CCR0, run_compiled_code);
 135     // Null method test is replicated below in compiled case,
 136     // it might be able to address across the verify_thread()
 137     __ cmplwi(CCR0, R19_method, 0);
 138     __ beq(CCR0, L_no_such_method);
 139     __ ld(target, in_bytes(Method::interpreter_entry_offset()), R19_method);
 140     __ mtctr(target);
 141     __ bctr();
 142     __ BIND(run_compiled_code);
 143   }
 144 
 145   // Compiled case, either static or fall-through from runtime conditional
 146   __ cmplwi(CCR0, R19_method, 0);
 147   __ beq(CCR0, L_no_such_method);
 148 
 149   const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
 150                                                      Method::from_interpreted_offset();
 151   __ ld(target, in_bytes(entry_offset), R19_method);
 152   __ mtctr(target);
 153   __ bctr();
 154 
 155   __ bind(L_no_such_method);
 156   assert(StubRoutines::throw_AbstractMethodError_entry() != NULL, "not yet generated!");
 157   __ load_const_optimized(target, StubRoutines::throw_AbstractMethodError_entry());
 158   __ mtctr(target);
 159   __ bctr();
 160 }
 161 
 162 
 163 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
 164                                         Register recv, Register method_temp,
 165                                         Register temp2, Register temp3,
 166                                         bool for_compiler_entry) {
 167   BLOCK_COMMENT("jump_to_lambda_form {");
 168   // This is the initial entry point of a lazy method handle.
 169   // After type checking, it picks up the invoker from the LambdaForm.
 170   assert_different_registers(recv, method_temp, temp2);  // temp3 is only passed on
 171   assert(method_temp == R19_method, "required register for loading method");
 172 
 173   // Load the invoker, as MH -> MH.form -> LF.vmentry
 174   __ verify_oop(recv);
 175   __ load_heap_oop_not_null(method_temp, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes()), recv, temp2);
 176   __ verify_oop(method_temp);
 177   __ load_heap_oop_not_null(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes()), method_temp, temp2);
 178   __ verify_oop(method_temp);
 179   __ load_heap_oop_not_null(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()), method_temp);
 180   __ verify_oop(method_temp);
 181   __ ld(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes()), method_temp);
 182 
 183   if (VerifyMethodHandles && !for_compiler_entry) {
 184     // Make sure recv is already on stack.
 185     __ ld(temp2, in_bytes(Method::const_offset()), method_temp);
 186     __ load_sized_value(temp2, in_bytes(ConstMethod::size_of_parameters_offset()), temp2,
 187                         sizeof(u2), /*is_signed*/ false);
 188     // assert(sizeof(u2) == sizeof(ConstMethod::_size_of_parameters), "");
 189     Label L;
 190     __ ld(temp2, __ argument_offset(temp2, temp2, 0), R15_esp);
 191     __ cmpd(CCR1, temp2, recv);
 192     __ beq(CCR1, L);
 193     __ stop("receiver not on stack");
 194     __ BIND(L);
 195   }
 196 
 197   jump_from_method_handle(_masm, method_temp, temp2, temp3, for_compiler_entry);
 198   BLOCK_COMMENT("} jump_to_lambda_form");
 199 }
 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     __ stop("Should not reach here");           // empty stubs make SG sick
 214     return NULL;
 215   }
 216 
 217   Register argbase    = R15_esp; // parameter (preserved)
 218   Register argslot    = R3;
 219   Register temp1      = R6;
 220   Register param_size = R7;
 221 
 222   // here's where control starts out:
 223   __ align(CodeEntryAlignment);
 224   address entry_point = __ pc();
 225 
 226   if (VerifyMethodHandles) {
 227     assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
 228 
 229     Label L;
 230     BLOCK_COMMENT("verify_intrinsic_id {");
 231     __ load_sized_value(temp1, Method::intrinsic_id_offset_in_bytes(), R19_method,
 232                         sizeof(u2), /*is_signed*/ false);
 233     __ cmpwi(CCR1, temp1, (int) iid);
 234     __ beq(CCR1, L);
 235     if (iid == vmIntrinsics::_linkToVirtual ||
 236         iid == vmIntrinsics::_linkToSpecial) {
 237       // could do this for all kinds, but would explode assembly code size
 238       trace_method_handle(_masm, "bad Method*:intrinsic_id");
 239     }
 240     __ stop("bad Method*::intrinsic_id");
 241     __ BIND(L);
 242     BLOCK_COMMENT("} verify_intrinsic_id");
 243   }
 244 
 245   // First task:  Find out how big the argument list is.
 246   int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
 247   assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
 248   if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
 249     __ ld(param_size, in_bytes(Method::const_offset()), R19_method);
 250     __ load_sized_value(param_size, in_bytes(ConstMethod::size_of_parameters_offset()), param_size,
 251                         sizeof(u2), /*is_signed*/ false);
 252     // assert(sizeof(u2) == sizeof(ConstMethod::_size_of_parameters), "");
 253   } else {
 254     DEBUG_ONLY(param_size = noreg);
 255   }
 256 
 257   Register tmp_mh = noreg;
 258   if (!is_signature_polymorphic_static(iid)) {
 259     __ ld(tmp_mh = temp1, __ argument_offset(param_size, param_size, 0), argbase);
 260     DEBUG_ONLY(param_size = noreg);
 261   }
 262 
 263   if (TraceMethodHandles) {
 264     if (tmp_mh != noreg) {
 265       __ mr(R23_method_handle, tmp_mh);  // make stub happy
 266     }
 267     trace_method_handle_interpreter_entry(_masm, iid);
 268   }
 269 
 270   if (iid == vmIntrinsics::_invokeBasic) {
 271     generate_method_handle_dispatch(_masm, iid, tmp_mh, noreg, not_for_compiler_entry);
 272 
 273   } else {
 274     // Adjust argument list by popping the trailing MemberName argument.
 275     Register tmp_recv = noreg;
 276     if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
 277       // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
 278       __ ld(tmp_recv = temp1, __ argument_offset(param_size, param_size, 0), argbase);
 279       DEBUG_ONLY(param_size = noreg);
 280     }
 281     Register R19_member = R19_method;  // MemberName ptr; incoming method ptr is dead now
 282     __ ld(R19_member, RegisterOrConstant((intptr_t)8), argbase);
 283     __ add(argbase, Interpreter::stackElementSize, argbase);
 284     generate_method_handle_dispatch(_masm, iid, tmp_recv, R19_member, not_for_compiler_entry);
 285   }
 286 
 287   return entry_point;
 288 }
 289 
 290 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
 291                                                     vmIntrinsics::ID iid,
 292                                                     Register receiver_reg,
 293                                                     Register member_reg,
 294                                                     bool for_compiler_entry) {
 295   assert(is_signature_polymorphic(iid), "expected invoke iid");
 296   Register temp1 = (for_compiler_entry ? R25_tmp5 : R7);
 297   Register temp2 = (for_compiler_entry ? R22_tmp2 : R8);
 298   Register temp3 = (for_compiler_entry ? R23_tmp3 : R9);
 299   Register temp4 = (for_compiler_entry ? R24_tmp4 : R10);
 300   if (receiver_reg != noreg)  assert_different_registers(temp1, temp2, temp3, temp4, receiver_reg);
 301   if (member_reg   != noreg)  assert_different_registers(temp1, temp2, temp3, temp4, member_reg);
 302 
 303   if (iid == vmIntrinsics::_invokeBasic) {
 304     // indirect through MH.form.vmentry.vmtarget
 305     jump_to_lambda_form(_masm, receiver_reg, R19_method, temp1, temp2, for_compiler_entry);
 306   } else {
 307     // The method is a member invoker used by direct method handles.
 308     if (VerifyMethodHandles) {
 309       // make sure the trailing argument really is a MemberName (caller responsibility)
 310       verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(MemberName_klass),
 311                    temp1, temp2,
 312                    "MemberName required for invokeVirtual etc.");
 313     }
 314 
 315     Register temp1_recv_klass = temp1;
 316     if (iid != vmIntrinsics::_linkToStatic) {
 317       __ verify_oop(receiver_reg);
 318       if (iid == vmIntrinsics::_linkToSpecial) {
 319         // Don't actually load the klass; just null-check the receiver.
 320         __ null_check_throw(receiver_reg, -1, temp1,
 321                             Interpreter::throw_NullPointerException_entry());
 322       } else {
 323         // load receiver klass itself
 324         __ null_check_throw(receiver_reg, oopDesc::klass_offset_in_bytes(), temp1,
 325                             Interpreter::throw_NullPointerException_entry());
 326         __ load_klass(temp1_recv_klass, receiver_reg);
 327         __ verify_klass_ptr(temp1_recv_klass);
 328       }
 329       BLOCK_COMMENT("check_receiver {");
 330       // The receiver for the MemberName must be in receiver_reg.
 331       // Check the receiver against the MemberName.clazz
 332       if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
 333         // Did not load it above...
 334         __ load_klass(temp1_recv_klass, receiver_reg);
 335         __ verify_klass_ptr(temp1_recv_klass);
 336       }
 337       if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
 338         Label L_ok;
 339         Register temp2_defc = temp2;
 340         __ load_heap_oop_not_null(temp2_defc, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()), member_reg, temp3);
 341         load_klass_from_Class(_masm, temp2_defc, temp3, temp4);
 342         __ verify_klass_ptr(temp2_defc);
 343         __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, temp4, L_ok);
 344         // If we get here, the type check failed!
 345         __ stop("receiver class disagrees with MemberName.clazz");
 346         __ BIND(L_ok);
 347       }
 348       BLOCK_COMMENT("} check_receiver");
 349     }
 350     if (iid == vmIntrinsics::_linkToSpecial ||
 351         iid == vmIntrinsics::_linkToStatic) {
 352       DEBUG_ONLY(temp1_recv_klass = noreg);  // these guys didn't load the recv_klass
 353     }
 354 
 355     // Live registers at this point:
 356     //  member_reg - MemberName that was the trailing argument
 357     //  temp1_recv_klass - klass of stacked receiver, if needed
 358     //  O5_savedSP - interpreter linkage (if interpreted)
 359     //  O0..O5 - compiler arguments (if compiled)
 360 
 361     Label L_incompatible_class_change_error;
 362     switch (iid) {
 363     case vmIntrinsics::_linkToSpecial:
 364       if (VerifyMethodHandles) {
 365         verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp2);
 366       }
 367       __ load_heap_oop(R19_method, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()), member_reg);
 368       __ ld(R19_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes()), R19_method);
 369       break;
 370 
 371     case vmIntrinsics::_linkToStatic:
 372       if (VerifyMethodHandles) {
 373         verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp2);
 374       }
 375       __ load_heap_oop(R19_method, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()), member_reg);
 376       __ ld(R19_method, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes()), R19_method);
 377       break;
 378 
 379     case vmIntrinsics::_linkToVirtual:
 380     {
 381       // same as TemplateTable::invokevirtual,
 382       // minus the CP setup and profiling:
 383 
 384       if (VerifyMethodHandles) {
 385         verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp2);
 386       }
 387 
 388       // pick out the vtable index from the MemberName, and then we can discard it:
 389       Register temp2_index = temp2;
 390       __ ld(temp2_index, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()), member_reg);
 391 
 392       if (VerifyMethodHandles) {
 393         Label L_index_ok;
 394         __ cmpdi(CCR1, temp2_index, 0);
 395         __ bge(CCR1, L_index_ok);
 396         __ stop("no virtual index");
 397         __ BIND(L_index_ok);
 398       }
 399 
 400       // Note:  The verifier invariants allow us to ignore MemberName.clazz and vmtarget
 401       // at this point.  And VerifyMethodHandles has already checked clazz, if needed.
 402 
 403       // get target Method* & entry point
 404       __ lookup_virtual_method(temp1_recv_klass, temp2_index, R19_method);
 405       break;
 406     }
 407 
 408     case vmIntrinsics::_linkToInterface:
 409     {
 410       // same as TemplateTable::invokeinterface
 411       // (minus the CP setup and profiling, with different argument motion)
 412       if (VerifyMethodHandles) {
 413         verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp2);
 414       }
 415 
 416       Register temp2_intf = temp2;
 417       __ load_heap_oop_not_null(temp2_intf, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()), member_reg, temp3);
 418       load_klass_from_Class(_masm, temp2_intf, temp3, temp4);
 419       __ verify_klass_ptr(temp2_intf);
 420 
 421       Register vtable_index = R19_method;
 422       __ ld(vtable_index, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()), member_reg);
 423       if (VerifyMethodHandles) {
 424         Label L_index_ok;
 425         __ cmpdi(CCR1, vtable_index, 0);
 426         __ bge(CCR1, L_index_ok);
 427         __ stop("invalid vtable index for MH.invokeInterface");
 428         __ BIND(L_index_ok);
 429       }
 430 
 431       // given intf, index, and recv klass, dispatch to the implementation method
 432       __ lookup_interface_method(temp1_recv_klass, temp2_intf,
 433                                  // note: next two args must be the same:
 434                                  vtable_index, R19_method,
 435                                  temp3, temp4,
 436                                  L_incompatible_class_change_error);
 437       break;
 438     }
 439 
 440     default:
 441       fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid));
 442       break;
 443     }
 444 
 445     // Live at this point:
 446     //   R19_method
 447     //   O5_savedSP (if interpreted)
 448 
 449     // After figuring out which concrete method to call, jump into it.
 450     // Note that this works in the interpreter with no data motion.
 451     // But the compiled version will require that rcx_recv be shifted out.
 452     __ verify_method_ptr(R19_method);
 453     jump_from_method_handle(_masm, R19_method, temp1, temp2, for_compiler_entry);
 454 
 455     if (iid == vmIntrinsics::_linkToInterface) {
 456       __ BIND(L_incompatible_class_change_error);
 457       __ load_const_optimized(temp1, StubRoutines::throw_IncompatibleClassChangeError_entry());
 458       __ mtctr(temp1);
 459       __ bctr();
 460     }
 461   }
 462 }
 463 
 464 #ifndef PRODUCT
 465 void trace_method_handle_stub(const char* adaptername,
 466                               oopDesc* mh,
 467                               intptr_t* entry_sp,
 468                               intptr_t* saved_regs) {
 469 
 470   bool has_mh = (strstr(adaptername, "/static") == NULL &&
 471                  strstr(adaptername, "linkTo") == NULL);    // static linkers don't have MH
 472   const char* mh_reg_name = has_mh ? "R23_method_handle" : "G23";
 473   tty->print_cr("MH %s %s=" INTPTR_FORMAT " sp=" INTPTR_FORMAT,
 474                 adaptername, mh_reg_name, p2i(mh), p2i(entry_sp));
 475 
 476   if (Verbose) {
 477     tty->print_cr("Registers:");
 478     const int abi_offset = frame::abi_reg_args_size / 8;
 479     for (int i = R3->encoding(); i <= R12->encoding(); i++) {
 480       Register r = as_Register(i);
 481       int count = i - R3->encoding();
 482       // The registers are stored in reverse order on the stack (by save_volatile_gprs(R1_SP, abi_reg_args_size)).
 483       tty->print("%3s=" PTR_FORMAT, r->name(), saved_regs[abi_offset + count]);
 484       if ((count + 1) % 4 == 0) {
 485         tty->cr();
 486       } else {
 487         tty->print(", ");
 488       }
 489     }
 490     tty->cr();
 491 
 492     {
 493       // dumping last frame with frame::describe
 494 
 495       JavaThread* p = JavaThread::active();
 496 
 497       ResourceMark rm;
 498       PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here
 499       FrameValues values;
 500 
 501       // Note: We want to allow trace_method_handle from any call site.
 502       // While trace_method_handle creates a frame, it may be entered
 503       // without a PC on the stack top (e.g. not just after a call).
 504       // Walking that frame could lead to failures due to that invalid PC.
 505       // => carefully detect that frame when doing the stack walking
 506 
 507       // Current C frame
 508       frame cur_frame = os::current_frame();
 509 
 510       // Robust search of trace_calling_frame (independant of inlining).
 511       assert(cur_frame.sp() <= saved_regs, "registers not saved on stack ?");
 512       frame trace_calling_frame = os::get_sender_for_C_frame(&cur_frame);
 513       while (trace_calling_frame.fp() < saved_regs) {
 514         trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame);
 515       }
 516 
 517       // Safely create a frame and call frame::describe.
 518       intptr_t *dump_sp = trace_calling_frame.sender_sp();
 519 
 520       frame dump_frame = frame(dump_sp);
 521       dump_frame.describe(values, 1);
 522 
 523       values.describe(-1, saved_regs, "raw top of stack");
 524 
 525       tty->print_cr("Stack layout:");
 526       values.print(p);
 527     }
 528 
 529     if (has_mh && oopDesc::is_oop(mh)) {
 530       mh->print();
 531       if (java_lang_invoke_MethodHandle::is_instance(mh)) {
 532         if (java_lang_invoke_MethodHandle::form_offset_in_bytes() != 0)
 533           java_lang_invoke_MethodHandle::form(mh)->print();
 534       }
 535     }
 536   }
 537 }
 538 
 539 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
 540   if (!TraceMethodHandles) return;
 541 
 542   BLOCK_COMMENT("trace_method_handle {");
 543 
 544   const Register tmp = R11; // Will be preserved.
 545   const int nbytes_save = MacroAssembler::num_volatile_regs * 8;
 546   __ save_volatile_gprs(R1_SP, -nbytes_save); // except R0
 547   __ save_LR_CR(tmp); // save in old frame
 548 
 549   __ mr(R5_ARG3, R1_SP);     // saved_sp
 550   __ push_frame_reg_args(nbytes_save, tmp);
 551 
 552   __ load_const_optimized(R3_ARG1, (address)adaptername, tmp);
 553   __ mr(R4_ARG2, R23_method_handle);
 554   __ mr(R6_ARG4, R1_SP);
 555   __ call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub));
 556 
 557   __ pop_frame();
 558   __ restore_LR_CR(tmp);
 559   __ restore_volatile_gprs(R1_SP, -nbytes_save); // except R0
 560 
 561   BLOCK_COMMENT("} trace_method_handle");
 562 }
 563 #endif // PRODUCT
--- EOF ---