src/cpu/x86/vm/methodHandles_x86.cpp

Tue, 24 Jul 2012 10:51:00 -0700

author
twisti
date
Tue, 24 Jul 2012 10:51:00 -0700
changeset 3969
1d7922586cf6
parent 3566
45a1bf98f1bb
child 4037
da91efe96a93
permissions
-rw-r--r--

7023639: JSR 292 method handle invocation needs a fast path for compiled code
6984705: JSR 292 method handle creation should not go through JNI
Summary: remove assembly code for JDK 7 chained method handles
Reviewed-by: jrose, twisti, kvn, mhaupt
Contributed-by: John Rose <john.r.rose@oracle.com>, Christian Thalinger <christian.thalinger@oracle.com>, Michael Haupt <michael.haupt@oracle.com>

     1 /*
     2  * Copyright (c) 1997, 2012, 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  */
    25 #include "precompiled.hpp"
    26 #include "interpreter/interpreter.hpp"
    27 #include "interpreter/interpreterRuntime.hpp"
    28 #include "memory/allocation.inline.hpp"
    29 #include "prims/methodHandles.hpp"
    31 #define __ _masm->
    33 #ifdef PRODUCT
    34 #define BLOCK_COMMENT(str) /* nothing */
    35 #define STOP(error) stop(error)
    36 #else
    37 #define BLOCK_COMMENT(str) __ block_comment(str)
    38 #define STOP(error) block_comment(error); __ stop(error)
    39 #endif
    41 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
    43 // Workaround for C++ overloading nastiness on '0' for RegisterOrConstant.
    44 static RegisterOrConstant constant(int value) {
    45   return RegisterOrConstant(value);
    46 }
    48 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) {
    49   if (VerifyMethodHandles)
    50     verify_klass(_masm, klass_reg, SystemDictionaryHandles::Class_klass(),
    51                  "MH argument is a Class");
    52   __ load_heap_oop(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes()));
    53 }
    55 #ifdef ASSERT
    56 static int check_nonzero(const char* xname, int x) {
    57   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
    65 #ifdef ASSERT
    66 void MethodHandles::verify_klass(MacroAssembler* _masm,
    67                                  Register obj, KlassHandle klass,
    68                                  const char* error_message) {
    69   oop* klass_addr = klass.raw_value();
    70   assert(klass_addr >= SystemDictionaryHandles::Object_klass().raw_value() &&
    71          klass_addr <= SystemDictionaryHandles::Long_klass().raw_value(),
    72          "must be one of the SystemDictionaryHandles");
    73   Register temp = rdi;
    74   Register temp2 = noreg;
    75   LP64_ONLY(temp2 = rscratch1);  // used by MacroAssembler::cmpptr
    76   Label L_ok, L_bad;
    77   BLOCK_COMMENT("verify_klass {");
    78   __ verify_oop(obj);
    79   __ testptr(obj, obj);
    80   __ jcc(Assembler::zero, L_bad);
    81   __ push(temp); if (temp2 != noreg)  __ push(temp2);
    82 #define UNPUSH { if (temp2 != noreg)  __ pop(temp2);  __ pop(temp); }
    83   __ load_klass(temp, obj);
    84   __ cmpptr(temp, ExternalAddress((address) klass_addr));
    85   __ jcc(Assembler::equal, L_ok);
    86   intptr_t super_check_offset = klass->super_check_offset();
    87   __ movptr(temp, Address(temp, super_check_offset));
    88   __ cmpptr(temp, ExternalAddress((address) klass_addr));
    89   __ jcc(Assembler::equal, L_ok);
    90   UNPUSH;
    91   __ bind(L_bad);
    92   __ STOP(error_message);
    93   __ BIND(L_ok);
    94   UNPUSH;
    95   BLOCK_COMMENT("} verify_klass");
    96 }
    98 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {
    99   Label L;
   100   BLOCK_COMMENT("verify_ref_kind {");
   101   __ movl(temp, Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes())));
   102   __ shrl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT);
   103   __ andl(temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK);
   104   __ cmpl(temp, ref_kind);
   105   __ jcc(Assembler::equal, 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 }
   118 #endif //ASSERT
   120 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
   121                                             bool for_compiler_entry) {
   122   assert(method == rbx, "interpreter calling convention");
   123   __ verify_oop(method);
   125   if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
   126     Label run_compiled_code;
   127     // JVMTI events, such as single-stepping, are implemented partly by avoiding running
   128     // compiled code in threads for which the event is enabled.  Check here for
   129     // interp_only_mode if these events CAN be enabled.
   130 #ifdef _LP64
   131     Register rthread = r15_thread;
   132 #else
   133     Register rthread = temp;
   134     __ get_thread(rthread);
   135 #endif
   136     // interp_only is an int, on little endian it is sufficient to test the byte only
   137     // Is a cmpl faster?
   138     __ cmpb(Address(rthread, JavaThread::interp_only_mode_offset()), 0);
   139     __ jccb(Assembler::zero, run_compiled_code);
   140     __ jmp(Address(method, methodOopDesc::interpreter_entry_offset()));
   141     __ BIND(run_compiled_code);
   142   }
   144   const ByteSize entry_offset = for_compiler_entry ? methodOopDesc::from_compiled_offset() :
   145                                                      methodOopDesc::from_interpreted_offset();
   146   __ jmp(Address(method, entry_offset));
   147 }
   149 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
   150                                         Register recv, Register method_temp,
   151                                         Register temp2,
   152                                         bool for_compiler_entry) {
   153   BLOCK_COMMENT("jump_to_lambda_form {");
   154   // This is the initial entry point of a lazy method handle.
   155   // After type checking, it picks up the invoker from the LambdaForm.
   156   assert_different_registers(recv, method_temp, temp2);
   157   assert(recv != noreg, "required register");
   158   assert(method_temp == rbx, "required register for loading method");
   160   //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); });
   162   // Load the invoker, as MH -> MH.form -> LF.vmentry
   163   __ verify_oop(recv);
   164   __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())));
   165   __ verify_oop(method_temp);
   166   __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())));
   167   __ verify_oop(method_temp);
   168   // the following assumes that a methodOop is normally compressed in the vmtarget field:
   169   __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::vmtarget_offset_in_bytes())));
   170   __ verify_oop(method_temp);
   172   if (VerifyMethodHandles && !for_compiler_entry) {
   173     // make sure recv is already on stack
   174     __ load_sized_value(temp2,
   175                         Address(method_temp, methodOopDesc::size_of_parameters_offset()),
   176                         sizeof(u2), /*is_signed*/ false);
   177     // assert(sizeof(u2) == sizeof(methodOopDesc::_size_of_parameters), "");
   178     Label L;
   179     __ cmpptr(recv, __ argument_address(temp2, -1));
   180     __ jcc(Assembler::equal, L);
   181     __ movptr(rax, __ argument_address(temp2, -1));
   182     __ STOP("receiver not on stack");
   183     __ BIND(L);
   184   }
   186   jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
   187   BLOCK_COMMENT("} jump_to_lambda_form");
   188 }
   191 // Code generation
   192 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
   193                                                                 vmIntrinsics::ID iid) {
   194   const bool not_for_compiler_entry = false;  // this is the interpreter entry
   195   assert(is_signature_polymorphic(iid), "expected invoke iid");
   196   if (iid == vmIntrinsics::_invokeGeneric ||
   197       iid == vmIntrinsics::_compiledLambdaForm) {
   198     // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
   199     // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
   200     // They all allow an appendix argument.
   201     __ hlt();           // empty stubs make SG sick
   202     return NULL;
   203   }
   205   // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
   206   // rbx: methodOop
   207   // rdx: argument locator (parameter slot count, added to rsp)
   208   // rcx: used as temp to hold mh or receiver
   209   // rax, rdi: garbage temps, blown away
   210   Register rdx_argp   = rdx;   // argument list ptr, live on error paths
   211   Register rax_temp   = rax;
   212   Register rcx_mh     = rcx;   // MH receiver; dies quickly and is recycled
   213   Register rbx_method = rbx;   // eventual target of this invocation
   215   address code_start = __ pc();
   217   // here's where control starts out:
   218   __ align(CodeEntryAlignment);
   219   address entry_point = __ pc();
   221   if (VerifyMethodHandles) {
   222     Label L;
   223     BLOCK_COMMENT("verify_intrinsic_id {");
   224     __ cmpb(Address(rbx_method, methodOopDesc::intrinsic_id_offset_in_bytes()), (int) iid);
   225     __ jcc(Assembler::equal, L);
   226     if (iid == vmIntrinsics::_linkToVirtual ||
   227         iid == vmIntrinsics::_linkToSpecial) {
   228       // could do this for all kinds, but would explode assembly code size
   229       trace_method_handle(_masm, "bad methodOop::intrinsic_id");
   230     }
   231     __ STOP("bad methodOop::intrinsic_id");
   232     __ bind(L);
   233     BLOCK_COMMENT("} verify_intrinsic_id");
   234   }
   236   // First task:  Find out how big the argument list is.
   237   Address rdx_first_arg_addr;
   238   int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
   239   assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
   240   if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
   241     __ load_sized_value(rdx_argp,
   242                         Address(rbx_method, methodOopDesc::size_of_parameters_offset()),
   243                         sizeof(u2), /*is_signed*/ false);
   244     // assert(sizeof(u2) == sizeof(methodOopDesc::_size_of_parameters), "");
   245     rdx_first_arg_addr = __ argument_address(rdx_argp, -1);
   246   } else {
   247     DEBUG_ONLY(rdx_argp = noreg);
   248   }
   250   if (!is_signature_polymorphic_static(iid)) {
   251     __ movptr(rcx_mh, rdx_first_arg_addr);
   252     DEBUG_ONLY(rdx_argp = noreg);
   253   }
   255   // rdx_first_arg_addr is live!
   257   if (TraceMethodHandles) {
   258     const char* name = vmIntrinsics::name_at(iid);
   259     if (*name == '_')  name += 1;
   260     const size_t len = strlen(name) + 50;
   261     char* qname = NEW_C_HEAP_ARRAY(char, len, mtInternal);
   262     const char* suffix = "";
   263     if (vmIntrinsics::method_for(iid) == NULL ||
   264         !vmIntrinsics::method_for(iid)->access_flags().is_public()) {
   265       if (is_signature_polymorphic_static(iid))
   266         suffix = "/static";
   267       else
   268         suffix = "/private";
   269     }
   270     jio_snprintf(qname, len, "MethodHandle::interpreter_entry::%s%s", name, suffix);
   271     // note: stub look for mh in rcx
   272     trace_method_handle(_masm, qname);
   273   }
   275   if (iid == vmIntrinsics::_invokeBasic) {
   276     generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);
   278   } else {
   279     // Adjust argument list by popping the trailing MemberName argument.
   280     Register rcx_recv = noreg;
   281     if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
   282       // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
   283       __ movptr(rcx_recv = rcx, rdx_first_arg_addr);
   284     }
   285     DEBUG_ONLY(rdx_argp = noreg);
   286     Register rbx_member = rbx_method;  // MemberName ptr; incoming method ptr is dead now
   287     __ pop(rax_temp);           // return address
   288     __ pop(rbx_member);         // extract last argument
   289     __ push(rax_temp);          // re-push return address
   290     generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);
   291   }
   293   if (PrintMethodHandleStubs) {
   294     address code_end = __ pc();
   295     tty->print_cr("--------");
   296     tty->print_cr("method handle interpreter entry for %s", vmIntrinsics::name_at(iid));
   297     Disassembler::decode(code_start, code_end);
   298     tty->cr();
   299   }
   301   return entry_point;
   302 }
   304 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
   305                                                     vmIntrinsics::ID iid,
   306                                                     Register receiver_reg,
   307                                                     Register member_reg,
   308                                                     bool for_compiler_entry) {
   309   assert(is_signature_polymorphic(iid), "expected invoke iid");
   310   Register rbx_method = rbx;   // eventual target of this invocation
   311   // temps used in this code are not used in *either* compiled or interpreted calling sequences
   312 #ifdef _LP64
   313   Register temp1 = rscratch1;
   314   Register temp2 = rscratch2;
   315   Register temp3 = rax;
   316   if (for_compiler_entry) {
   317     assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment");
   318     assert_different_registers(temp1,        j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
   319     assert_different_registers(temp2,        j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
   320     assert_different_registers(temp3,        j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5);
   321   }
   322 #else
   323   Register temp1 = (for_compiler_entry ? rsi : rdx);
   324   Register temp2 = rdi;
   325   Register temp3 = rax;
   326   if (for_compiler_entry) {
   327     assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : rcx), "only valid assignment");
   328     assert_different_registers(temp1,        rcx, rdx);
   329     assert_different_registers(temp2,        rcx, rdx);
   330     assert_different_registers(temp3,        rcx, rdx);
   331   }
   332 #endif
   333   assert_different_registers(temp1, temp2, temp3, receiver_reg);
   334   assert_different_registers(temp1, temp2, temp3, member_reg);
   335   if (!for_compiler_entry)
   336     assert_different_registers(temp1, temp2, temp3, saved_last_sp_register());  // don't trash lastSP
   338   if (iid == vmIntrinsics::_invokeBasic) {
   339     // indirect through MH.form.vmentry.vmtarget
   340     jump_to_lambda_form(_masm, receiver_reg, rbx_method, temp1, for_compiler_entry);
   342   } else {
   343     // The method is a member invoker used by direct method handles.
   344     if (VerifyMethodHandles) {
   345       // make sure the trailing argument really is a MemberName (caller responsibility)
   346       verify_klass(_masm, member_reg, SystemDictionaryHandles::MemberName_klass(),
   347                    "MemberName required for invokeVirtual etc.");
   348     }
   350     Address member_clazz(    member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()));
   351     Address member_vmindex(  member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()));
   352     Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::vmtarget_offset_in_bytes()));
   354     Register temp1_recv_klass = temp1;
   355     if (iid != vmIntrinsics::_linkToStatic) {
   356       __ verify_oop(receiver_reg);
   357       if (iid == vmIntrinsics::_linkToSpecial) {
   358         // Don't actually load the klass; just null-check the receiver.
   359         __ null_check(receiver_reg);
   360       } else {
   361         // load receiver klass itself
   362         __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes());
   363         __ load_klass(temp1_recv_klass, receiver_reg);
   364         __ verify_oop(temp1_recv_klass);
   365       }
   366       BLOCK_COMMENT("check_receiver {");
   367       // The receiver for the MemberName must be in receiver_reg.
   368       // Check the receiver against the MemberName.clazz
   369       if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
   370         // Did not load it above...
   371         __ load_klass(temp1_recv_klass, receiver_reg);
   372         __ verify_oop(temp1_recv_klass);
   373       }
   374       if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
   375         Label L_ok;
   376         Register temp2_defc = temp2;
   377         __ load_heap_oop(temp2_defc, member_clazz);
   378         load_klass_from_Class(_masm, temp2_defc);
   379         __ verify_oop(temp2_defc);
   380         __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
   381         // If we get here, the type check failed!
   382         __ STOP("receiver class disagrees with MemberName.clazz");
   383         __ bind(L_ok);
   384       }
   385       BLOCK_COMMENT("} check_receiver");
   386     }
   387     if (iid == vmIntrinsics::_linkToSpecial ||
   388         iid == vmIntrinsics::_linkToStatic) {
   389       DEBUG_ONLY(temp1_recv_klass = noreg);  // these guys didn't load the recv_klass
   390     }
   392     // Live registers at this point:
   393     //  member_reg - MemberName that was the trailing argument
   394     //  temp1_recv_klass - klass of stacked receiver, if needed
   395     //  rsi/r13 - interpreter linkage (if interpreted)
   396     //  rcx, rdx, rsi, rdi, r8, r8 - compiler arguments (if compiled)
   398     bool method_is_live = false;
   399     switch (iid) {
   400     case vmIntrinsics::_linkToSpecial:
   401       if (VerifyMethodHandles) {
   402         verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
   403       }
   404       __ load_heap_oop(rbx_method, member_vmtarget);
   405       method_is_live = true;
   406       break;
   408     case vmIntrinsics::_linkToStatic:
   409       if (VerifyMethodHandles) {
   410         verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
   411       }
   412       __ load_heap_oop(rbx_method, member_vmtarget);
   413       method_is_live = true;
   414       break;
   416     case vmIntrinsics::_linkToVirtual:
   417     {
   418       // same as TemplateTable::invokevirtual,
   419       // minus the CP setup and profiling:
   421       if (VerifyMethodHandles) {
   422         verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
   423       }
   425       // pick out the vtable index from the MemberName, and then we can discard it:
   426       Register temp2_index = temp2;
   427       __ movptr(temp2_index, member_vmindex);
   429       if (VerifyMethodHandles) {
   430         Label L_index_ok;
   431         __ cmpl(temp2_index, 0);
   432         __ jcc(Assembler::greaterEqual, L_index_ok);
   433         __ STOP("no virtual index");
   434         __ BIND(L_index_ok);
   435       }
   437       // Note:  The verifier invariants allow us to ignore MemberName.clazz and vmtarget
   438       // at this point.  And VerifyMethodHandles has already checked clazz, if needed.
   440       // get target methodOop & entry point
   441       __ lookup_virtual_method(temp1_recv_klass, temp2_index, rbx_method);
   442       method_is_live = true;
   443       break;
   444     }
   446     case vmIntrinsics::_linkToInterface:
   447     {
   448       // same as TemplateTable::invokeinterface
   449       // (minus the CP setup and profiling, with different argument motion)
   450       if (VerifyMethodHandles) {
   451         verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
   452       }
   454       Register temp3_intf = temp3;
   455       __ load_heap_oop(temp3_intf, member_clazz);
   456       load_klass_from_Class(_masm, temp3_intf);
   457       __ verify_oop(temp3_intf);
   459       Register rbx_index = rbx_method;
   460       __ movptr(rbx_index, member_vmindex);
   461       if (VerifyMethodHandles) {
   462         Label L;
   463         __ cmpl(rbx_index, 0);
   464         __ jcc(Assembler::greaterEqual, L);
   465         __ STOP("invalid vtable index for MH.invokeInterface");
   466         __ bind(L);
   467       }
   469       // given intf, index, and recv klass, dispatch to the implementation method
   470       Label L_no_such_interface;
   471       __ lookup_interface_method(temp1_recv_klass, temp3_intf,
   472                                  // note: next two args must be the same:
   473                                  rbx_index, rbx_method,
   474                                  temp2,
   475                                  L_no_such_interface);
   477       __ verify_oop(rbx_method);
   478       jump_from_method_handle(_masm, rbx_method, temp2, for_compiler_entry);
   479       __ hlt();
   481       __ bind(L_no_such_interface);
   482       __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
   483       break;
   484     }
   486     default:
   487       fatal(err_msg("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid)));
   488       break;
   489     }
   491     if (method_is_live) {
   492       // live at this point:  rbx_method, rsi/r13 (if interpreted)
   494       // After figuring out which concrete method to call, jump into it.
   495       // Note that this works in the interpreter with no data motion.
   496       // But the compiled version will require that rcx_recv be shifted out.
   497       __ verify_oop(rbx_method);
   498       jump_from_method_handle(_masm, rbx_method, temp1, for_compiler_entry);
   499     }
   500   }
   501 }
   503 #ifndef PRODUCT
   504 void trace_method_handle_stub(const char* adaptername,
   505                               oop mh,
   506                               intptr_t* saved_regs,
   507                               intptr_t* entry_sp) {
   508   // called as a leaf from native code: do not block the JVM!
   509   bool has_mh = (strstr(adaptername, "/static") == NULL &&
   510                  strstr(adaptername, "linkTo") == NULL);    // static linkers don't have MH
   511   const char* mh_reg_name = has_mh ? "rcx_mh" : "rcx";
   512   tty->print_cr("MH %s %s="PTR_FORMAT" sp="PTR_FORMAT,
   513                 adaptername, mh_reg_name,
   514                 mh, entry_sp);
   516   if (Verbose) {
   517     tty->print_cr("Registers:");
   518     const int saved_regs_count = RegisterImpl::number_of_registers;
   519     for (int i = 0; i < saved_regs_count; i++) {
   520       Register r = as_Register(i);
   521       // The registers are stored in reverse order on the stack (by pusha).
   522       tty->print("%3s=" PTR_FORMAT, r->name(), saved_regs[((saved_regs_count - 1) - i)]);
   523       if ((i + 1) % 4 == 0) {
   524         tty->cr();
   525       } else {
   526         tty->print(", ");
   527       }
   528     }
   529     tty->cr();
   531     {
   532      // dumping last frame with frame::describe
   534       JavaThread* p = JavaThread::active();
   536       ResourceMark rm;
   537       PRESERVE_EXCEPTION_MARK; // may not be needed by safer and unexpensive here
   538       FrameValues values;
   540       // Note: We want to allow trace_method_handle from any call site.
   541       // While trace_method_handle creates a frame, it may be entered
   542       // without a PC on the stack top (e.g. not just after a call).
   543       // Walking that frame could lead to failures due to that invalid PC.
   544       // => carefully detect that frame when doing the stack walking
   546       // Current C frame
   547       frame cur_frame = os::current_frame();
   549       // Robust search of trace_calling_frame (independant of inlining).
   550       // Assumes saved_regs comes from a pusha in the trace_calling_frame.
   551       assert(cur_frame.sp() < saved_regs, "registers not saved on stack ?");
   552       frame trace_calling_frame = os::get_sender_for_C_frame(&cur_frame);
   553       while (trace_calling_frame.fp() < saved_regs) {
   554         trace_calling_frame = os::get_sender_for_C_frame(&trace_calling_frame);
   555       }
   557       // safely create a frame and call frame::describe
   558       intptr_t *dump_sp = trace_calling_frame.sender_sp();
   559       intptr_t *dump_fp = trace_calling_frame.link();
   561       bool walkable = has_mh; // whether the traced frame shoud be walkable
   563       if (walkable) {
   564         // The previous definition of walkable may have to be refined
   565         // if new call sites cause the next frame constructor to start
   566         // failing. Alternatively, frame constructors could be
   567         // modified to support the current or future non walkable
   568         // frames (but this is more intrusive and is not considered as
   569         // part of this RFE, which will instead use a simpler output).
   570         frame dump_frame = frame(dump_sp, dump_fp);
   571         dump_frame.describe(values, 1);
   572       } else {
   573         // Stack may not be walkable (invalid PC above FP):
   574         // Add descriptions without building a Java frame to avoid issues
   575         values.describe(-1, dump_fp, "fp for #1 <not parsed, cannot trust pc>");
   576         values.describe(-1, dump_sp, "sp for #1");
   577       }
   578       values.describe(-1, entry_sp, "raw top of stack");
   580       tty->print_cr("Stack layout:");
   581       values.print(p);
   582     }
   583     if (has_mh && mh->is_oop()) {
   584       mh->print();
   585       if (java_lang_invoke_MethodHandle::is_instance(mh)) {
   586         if (java_lang_invoke_MethodHandle::form_offset_in_bytes() != 0)
   587           java_lang_invoke_MethodHandle::form(mh)->print();
   588       }
   589     }
   590   }
   591 }
   593 // The stub wraps the arguments in a struct on the stack to avoid
   594 // dealing with the different calling conventions for passing 6
   595 // arguments.
   596 struct MethodHandleStubArguments {
   597   const char* adaptername;
   598   oopDesc* mh;
   599   intptr_t* saved_regs;
   600   intptr_t* entry_sp;
   601 };
   602 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) {
   603   trace_method_handle_stub(args->adaptername,
   604                            args->mh,
   605                            args->saved_regs,
   606                            args->entry_sp);
   607 }
   609 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
   610   if (!TraceMethodHandles)  return;
   611   BLOCK_COMMENT("trace_method_handle {");
   612   __ enter();
   613   __ andptr(rsp, -16); // align stack if needed for FPU state
   614   __ pusha();
   615   __ mov(rbx, rsp); // for retreiving saved_regs
   616   // Note: saved_regs must be in the entered frame for the
   617   // robust stack walking implemented in trace_method_handle_stub.
   619   // save FP result, valid at some call sites (adapter_opt_return_float, ...)
   620   __ increment(rsp, -2 * wordSize);
   621   if  (UseSSE >= 2) {
   622     __ movdbl(Address(rsp, 0), xmm0);
   623   } else if (UseSSE == 1) {
   624     __ movflt(Address(rsp, 0), xmm0);
   625   } else {
   626     __ fst_d(Address(rsp, 0));
   627   }
   629   // Incoming state:
   630   // rcx: method handle
   631   //
   632   // To avoid calling convention issues, build a record on the stack
   633   // and pass the pointer to that instead.
   634   __ push(rbp);               // entry_sp (with extra align space)
   635   __ push(rbx);               // pusha saved_regs
   636   __ push(rcx);               // mh
   637   __ push(rcx);               // slot for adaptername
   638   __ movptr(Address(rsp, 0), (intptr_t) adaptername);
   639   __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub_wrapper), rsp);
   640   __ increment(rsp, sizeof(MethodHandleStubArguments));
   642   if  (UseSSE >= 2) {
   643     __ movdbl(xmm0, Address(rsp, 0));
   644   } else if (UseSSE == 1) {
   645     __ movflt(xmm0, Address(rsp, 0));
   646   } else {
   647     __ fld_d(Address(rsp, 0));
   648   }
   649   __ increment(rsp, 2 * wordSize);
   651   __ popa();
   652   __ leave();
   653   BLOCK_COMMENT("} trace_method_handle");
   654 }
   655 #endif //PRODUCT

mercurial