/*

 * Copyright (c) 2008, 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

// This file mirror as much as possible methodHandles_x86.cpp to ease

// cross platform development for JSR292.

// Last synchronization: changeset f8c9417e3571

#include "precompiled.hpp"

#include "classfile/javaClasses.inline.hpp"

#include "interpreter/interpreter.hpp"

#include "interpreter/interpreterRuntime.hpp"

#include "memory/allocation.inline.hpp"

#include "memory/resourceArea.hpp"

#include "prims/methodHandles.hpp"

#define __ _masm->

#ifdef PRODUCT

#define BLOCK_COMMENT(str) /* nothing */

#else

#define BLOCK_COMMENT(str) __ block_comment(str)

#endif

#define BIND(label) bind(label); BLOCK_COMMENT(#label ":")

void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg, Register temp1, Register temp2) {

  if (VerifyMethodHandles) {

    verify_klass(_masm, klass_reg, temp1, temp2, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class),

                 "MH argument is a Class");

  }

  __ ldr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes()));

}

#ifdef ASSERT

static int check_nonzero(const char* xname, int x) {

  assert(x != 0, "%s should be nonzero", xname);

  return x;

}

#define NONZERO(x) check_nonzero(#x, x)

#else //ASSERT

#define NONZERO(x) (x)

#endif //ASSERT

#ifdef ASSERT

void MethodHandles::verify_klass(MacroAssembler* _masm,

                                 Register obj, Register temp1, Register temp2, SystemDictionary::WKID klass_id,

                                 const char* error_message) {

  InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id);

  Klass* klass = SystemDictionary::well_known_klass(klass_id);

  Label L_ok, L_bad;

  BLOCK_COMMENT("verify_klass {");

  __ verify_oop(obj);

  __ cbz(obj, L_bad);

  __ load_klass(temp1, obj);

  __ lea(temp2, ExternalAddress((address) klass_addr));

  __ ldr(temp2, temp2); // the cmpptr on x86 dereferences the AddressLiteral (not lea)

  __ cmp(temp1, temp2);

  __ b(L_ok, eq);

  intptr_t super_check_offset = klass->super_check_offset();

  __ ldr(temp1, Address(temp1, super_check_offset));

  __ cmp(temp1, temp2);

  __ b(L_ok, eq);

  __ bind(L_bad);

  __ stop(error_message);

  __ BIND(L_ok);

  BLOCK_COMMENT("} verify_klass");

}

void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) {

  Label L;

  BLOCK_COMMENT("verify_ref_kind {");

  __ ldr_u32(temp, Address(member_reg, NONZERO(java_lang_invoke_MemberName::flags_offset_in_bytes())));

  __ logical_shift_right(temp, temp, java_lang_invoke_MemberName::MN_REFERENCE_KIND_SHIFT);

  __ andr(temp, temp, (unsigned)java_lang_invoke_MemberName::MN_REFERENCE_KIND_MASK);

  __ cmp(temp, ref_kind);

  __ b(L, eq);

  { char* buf = NEW_C_HEAP_ARRAY(char, 100, mtInternal);

  jio_snprintf(buf, 100, "verify_ref_kind expected %x", ref_kind);

  if (ref_kind == JVM_REF_invokeVirtual ||

      ref_kind == JVM_REF_invokeSpecial)

    // could do this for all ref_kinds, but would explode assembly code size

    trace_method_handle(_masm, buf);

  __ stop(buf);

  }

  BLOCK_COMMENT("} verify_ref_kind");

  __ bind(L);

}

#endif //ASSERT

void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, bool for_compiler_entry) {

  Label L_no_such_method;

  __ cbz(Rmethod, L_no_such_method);

  // Note: JVMTI overhead seems small enough compared to invocation

  // cost and is not worth the complexity or code size overhead of

  // supporting several variants of each adapter.

  if (!for_compiler_entry && (JvmtiExport::can_post_interpreter_events())) {

    // JVMTI events, such as single-stepping, are implemented partly by avoiding running

    // compiled code in threads for which the event is enabled.  Check here for

    // interp_only_mode if these events CAN be enabled.

    __ ldr_s32(Rtemp, Address(Rthread, JavaThread::interp_only_mode_offset()));

#ifdef AARCH64

    Label L;

    __ cbz(Rtemp, L);

    __ indirect_jump(Address(Rmethod, Method::interpreter_entry_offset()), Rtemp);

    __ bind(L);

#else

    __ cmp(Rtemp, 0);

    __ ldr(PC, Address(Rmethod, Method::interpreter_entry_offset()), ne);

#endif // AARCH64

  }

  const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :

                                                     Method::from_interpreted_offset();

  __ indirect_jump(Address(Rmethod, entry_offset), Rtemp);

  __ bind(L_no_such_method);

  // throw exception

  __ jump(StubRoutines::throw_AbstractMethodError_entry(), relocInfo::runtime_call_type, Rtemp);

}

void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,

                                        Register recv, Register tmp,

                                        bool for_compiler_entry) {

  BLOCK_COMMENT("jump_to_lambda_form {");

  // This is the initial entry point of a lazy method handle.

  // After type checking, it picks up the invoker from the LambdaForm.

  assert_different_registers(recv, tmp, Rmethod);

  // Load the invoker, as MH -> MH.form -> LF.vmentry

  __ load_heap_oop(tmp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())));

  __ verify_oop(tmp);

  __ load_heap_oop(tmp, Address(tmp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())));

  __ verify_oop(tmp);

  if (VerifyMethodHandles && !for_compiler_entry) {

    // make sure recv is already on stack

    __ ldr(tmp, Address(Rmethod, Method::const_offset()));

    __ load_sized_value(tmp,

                        Address(tmp, ConstMethod::size_of_parameters_offset()),

                        sizeof(u2), /*is_signed*/ false);

    // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");

    Label L;

    __ ldr(tmp, __ receiver_argument_address(Rparams, tmp, tmp));

    __ cmp(tmp, recv);

    __ b(L, eq);

    __ stop("receiver not on stack");

    __ bind(L);

  }

  jump_from_method_handle(_masm, for_compiler_entry);

  BLOCK_COMMENT("} jump_to_lambda_form");

}

// Code generation

address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,

                                                                vmIntrinsics::ID iid) {

  const bool not_for_compiler_entry = false;  // this is the interpreter entry

  assert(is_signature_polymorphic(iid), "expected invoke iid");

  if (iid == vmIntrinsics::_invokeGeneric ||

      iid == vmIntrinsics::_compiledLambdaForm) {

    // Perhaps surprisingly, the user-visible names, and linkToCallSite, are not directly used.

    // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.

    // They all require an extra argument.

    __ should_not_reach_here();           // empty stubs make SG sick

    return NULL;

  }

  // Rmethod: Method*

  // Rparams (SP on 32-bit ARM): pointer to parameters

  // Rsender_sp (R4/R19): sender SP (must preserve; see prepare_to_jump_from_interpreted)

  // R5_mh: receiver method handle (must load from sp[MethodTypeForm.vmslots])

  // R1, R2, Rtemp: garbage temp, blown away

  // Use same name as x86 to ease future merges

  Register rdx_temp       = R2_tmp;

  Register rdx_param_size = rdx_temp;  // size of parameters

  Register rax_temp       = R1_tmp;

  Register rcx_mh         = R5_mh;     // MH receiver; dies quickly and is recycled

  Register rbx_method     = Rmethod;   // eventual target of this invocation

  Register rdi_temp       = Rtemp;

  // here's where control starts out:

  __ align(CodeEntryAlignment);

  address entry_point = __ pc();

  if (VerifyMethodHandles) {

    Label L;

    BLOCK_COMMENT("verify_intrinsic_id {");

    __ ldrh(rdi_temp, Address(rbx_method, Method::intrinsic_id_offset_in_bytes()));

    __ sub_slow(rdi_temp, rdi_temp, (int) iid);

    __ cbz(rdi_temp, L);

    if (iid == vmIntrinsics::_linkToVirtual ||

        iid == vmIntrinsics::_linkToSpecial) {

      // could do this for all kinds, but would explode assembly code size

      trace_method_handle(_masm, "bad Method*::intrinsic_id");

    }

    __ stop("bad Method*::intrinsic_id");

    __ bind(L);

    BLOCK_COMMENT("} verify_intrinsic_id");

  }

  // First task:  Find out how big the argument list is.

  Address rdx_first_arg_addr;

  int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);

  assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");

  if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {

    __ ldr(rdx_param_size, Address(rbx_method, Method::const_offset()));

    __ load_sized_value(rdx_param_size,

                        Address(rdx_param_size, ConstMethod::size_of_parameters_offset()),

                        sizeof(u2), /*is_signed*/ false);

    // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");

    rdx_first_arg_addr = __ receiver_argument_address(Rparams, rdx_param_size, rdi_temp);

  } else {

    DEBUG_ONLY(rdx_param_size = noreg);

  }

  if (!is_signature_polymorphic_static(iid)) {

    __ ldr(rcx_mh, rdx_first_arg_addr);

    DEBUG_ONLY(rdx_param_size = noreg);

  }

  // rdx_first_arg_addr is live!

  trace_method_handle_interpreter_entry(_masm, iid);

  if (iid == vmIntrinsics::_invokeBasic) {

    generate_method_handle_dispatch(_masm, iid, rcx_mh, noreg, not_for_compiler_entry);

  } else {

    // Adjust argument list by popping the trailing MemberName argument.

    Register rcx_recv = noreg;

    if (MethodHandles::ref_kind_has_receiver(ref_kind)) {

      // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.

      __ ldr(rcx_recv = rcx_mh, rdx_first_arg_addr);

      DEBUG_ONLY(rdx_param_size = noreg);

    }

    Register rbx_member = rbx_method;  // MemberName ptr; incoming method ptr is dead now

#ifdef AARCH64

    __ ldr(rbx_member, Address(Rparams, Interpreter::stackElementSize, post_indexed));

#else

    __ pop(rbx_member);

#endif

    generate_method_handle_dispatch(_masm, iid, rcx_recv, rbx_member, not_for_compiler_entry);

  }

  return entry_point;

}

void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,

                                                    vmIntrinsics::ID iid,

                                                    Register receiver_reg,

                                                    Register member_reg,

                                                    bool for_compiler_entry) {

  assert(is_signature_polymorphic(iid), "expected invoke iid");

  // Use same name as x86 to ease future merges

  Register rbx_method = Rmethod;   // eventual target of this invocation

  // temps used in this code are not used in *either* compiled or interpreted calling sequences

  Register temp1 = (for_compiler_entry ? saved_last_sp_register() : R1_tmp);

  Register temp2 = AARCH64_ONLY(R9) NOT_AARCH64(R8);

  Register temp3 = Rtemp; // R12/R16

  Register temp4 = AARCH64_ONLY(Rtemp2) NOT_AARCH64(R5);

  if (for_compiler_entry) {

    assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment");

#ifdef AARCH64

    assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);

    assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);

    assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);

    assert_different_registers(temp4, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);

#else

    assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3);

    assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3);

    assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3);

    assert_different_registers(temp4, j_rarg0, j_rarg1, j_rarg2, j_rarg3);

#endif // AARCH64

  }

  assert_different_registers(temp1, temp2, temp3, receiver_reg);

  assert_different_registers(temp1, temp2, temp3, temp4, member_reg);

  if (!for_compiler_entry)

    assert_different_registers(temp1, temp2, temp3, temp4, saved_last_sp_register());  // don't trash lastSP

  if (iid == vmIntrinsics::_invokeBasic) {

    // indirect through MH.form.exactInvoker.vmtarget

    jump_to_lambda_form(_masm, receiver_reg, temp3, for_compiler_entry);

  } else {

    // The method is a member invoker used by direct method handles.

    if (VerifyMethodHandles) {

      // make sure the trailing argument really is a MemberName (caller responsibility)

      verify_klass(_masm, member_reg, temp2, temp3, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_invoke_MemberName),

                   "MemberName required for invokeVirtual etc.");

    }

    Address member_clazz(   member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()));

    Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()));

    Register temp1_recv_klass = temp1;

    if (iid != vmIntrinsics::_linkToStatic) {

      if (iid == vmIntrinsics::_linkToSpecial) {

        // Don't actually load the klass; just null-check the receiver.

        __ null_check(receiver_reg, temp3);

      } else {

        // load receiver klass itself

        __ null_check(receiver_reg, temp3, oopDesc::klass_offset_in_bytes());

        __ load_klass(temp1_recv_klass, receiver_reg);

        __ verify_klass_ptr(temp1_recv_klass);

      }

      BLOCK_COMMENT("check_receiver {");

      // The receiver for the MemberName must be in receiver_reg.

      // Check the receiver against the MemberName.clazz

      if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {

        // Did not load it above...

        __ load_klass(temp1_recv_klass, receiver_reg);

        __ verify_klass_ptr(temp1_recv_klass);

      }

      // Check the receiver against the MemberName.clazz

      if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {

        Label L_ok;

        Register temp2_defc = temp2;

        __ load_heap_oop(temp2_defc, member_clazz);

        load_klass_from_Class(_masm, temp2_defc, temp3, temp4);

        __ verify_klass_ptr(temp2_defc);

#ifdef AARCH64

        // TODO-AARCH64

        __ b(L_ok);

#else

        __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, temp4, noreg, L_ok);

#endif

        // If we get here, the type check failed!

        __ stop("receiver class disagrees with MemberName.clazz");

        __ bind(L_ok);

      }

      BLOCK_COMMENT("} check_receiver");

    }

    if (iid == vmIntrinsics::_linkToSpecial ||

        iid == vmIntrinsics::_linkToStatic) {

      DEBUG_ONLY(temp1_recv_klass = noreg);  // these guys didn't load the recv_klass

    }

    // Live registers at this point:

    //  member_reg - MemberName that was the extra argument

    //  temp1_recv_klass - klass of stacked receiver, if needed

    Label L_incompatible_class_change_error;

    switch (iid) {

    case vmIntrinsics::_linkToSpecial:

      if (VerifyMethodHandles) {

        verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);

      }

      break;

    case vmIntrinsics::_linkToStatic:

      if (VerifyMethodHandles) {

        verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);

      }

      break;

    case vmIntrinsics::_linkToVirtual:

    {

      // same as TemplateTable::invokevirtual,

      // minus the CP setup and profiling:

      if (VerifyMethodHandles) {

        verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);

      }

      // pick out the vtable index from the MemberName, and then we can discard it:

      Register temp2_index = temp2;

      __ ldr(temp2_index, member_vmindex);

      if (VerifyMethodHandles) {

        Label L_index_ok;

        __ cmp(temp2_index, 0);

        __ b(L_index_ok, ge);

        __ stop("no virtual index");

        __ bind(L_index_ok);

      }

      // Note:  The verifier invariants allow us to ignore MemberName.clazz and vmtarget

      // at this point.  And VerifyMethodHandles has already checked clazz, if needed.

      // get target Method* & entry point

      __ lookup_virtual_method(temp1_recv_klass, temp2_index, Rmethod);

      break;

    }

    case vmIntrinsics::_linkToInterface:

    {

      // same as TemplateTable::invokeinterface

      // (minus the CP setup and profiling, with different argument motion)

      if (VerifyMethodHandles) {

        verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);

      }

      Register temp3_intf = temp3;

      __ load_heap_oop(temp3_intf, member_clazz);

      load_klass_from_Class(_masm, temp3_intf, temp2, temp4);

      __ verify_klass_ptr(temp3_intf);

      Register rbx_index = rbx_method;

      __ ldr(rbx_index, member_vmindex);

      if (VerifyMethodHandles) {

        Label L;

        __ cmp(rbx_index, 0);

        __ b(L, ge);

        __ stop("invalid vtable index for MH.invokeInterface");

        __ bind(L);

      }

      // given intf, index, and recv klass, dispatch to the implementation method

      Label L_no_such_interface;

      __ lookup_interface_method(temp1_recv_klass, temp3_intf,

                                 // note: next two args must be the same:

                                 rbx_index, rbx_method,

                                 temp2, temp4,

                                 L_incompatible_class_change_error);

      break;

    }

    default:

      fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid));

      break;

    }

    // Live at this point:

    //   Rmethod (target method)

    //   Rsender_sp, Rparams (if interpreted)

    //   register arguments (if compiled)

    // After figuring out which concrete method to call, jump into it.

    __ verify_method_ptr(Rmethod);

    jump_from_method_handle(_masm, for_compiler_entry);

    if (iid == vmIntrinsics::_linkToInterface) {

      __ bind(L_incompatible_class_change_error);

      __ jump(StubRoutines::throw_IncompatibleClassChangeError_entry(), relocInfo::runtime_call_type, Rtemp);

    }

  }

}

#ifndef PRODUCT

enum {

  ARG_LIMIT = 255, SLOP = 4,

  // use this parameter for checking for garbage stack movements:

  UNREASONABLE_STACK_MOVE = (ARG_LIMIT + SLOP)

  // the slop defends against false alarms due to fencepost errors

};

#ifdef AARCH64

const int trace_mh_nregs = 32; // R0-R30, PC

#else

const int trace_mh_nregs = 15;

const Register trace_mh_regs[trace_mh_nregs] =

  {R0, R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, LR, PC};

#endif // AARCH64

void trace_method_handle_stub(const char* adaptername,

                              intptr_t* saved_regs,

                              intptr_t* saved_bp,

                              oop mh) {

  // called as a leaf from native code: do not block the JVM!

  bool has_mh = (strstr(adaptername, "/static") == NULL &&

                 strstr(adaptername, "linkTo") == NULL);    // static linkers don't have MH

  intptr_t* entry_sp = (intptr_t*) &saved_regs[trace_mh_nregs]; // just after the saved regs

  intptr_t* saved_sp = (intptr_t*)  saved_regs[Rsender_sp->encoding()]; // save of Rsender_sp

  intptr_t* last_sp  = (intptr_t*)  saved_bp[AARCH64_ONLY(frame::interpreter_frame_stack_top_offset) NOT_AARCH64(frame::interpreter_frame_last_sp_offset)];

  intptr_t* base_sp  = last_sp;

  intptr_t    mh_reg = (intptr_t)saved_regs[R5_mh->encoding()];

  const char* mh_reg_name = "R5_mh";

  if (!has_mh)  mh_reg_name = "R5";

  tty->print_cr("MH %s %s=" PTR_FORMAT " sp=(" PTR_FORMAT "+" INTX_FORMAT ") stack_size=" INTX_FORMAT " bp=" PTR_FORMAT,

                adaptername, mh_reg_name, mh_reg,

                (intptr_t)entry_sp, (intptr_t)saved_sp - (intptr_t)entry_sp, (intptr_t)(base_sp - last_sp), (intptr_t)saved_bp);

  if (last_sp != saved_sp && last_sp != NULL)

    tty->print_cr("*** last_sp=" INTPTR_FORMAT, p2i(last_sp));

  if (Verbose) {

    tty->print(" reg dump: ");

    int i;

    for (i = 0; i < trace_mh_nregs; i++) {

      if (i > 0 && i % AARCH64_ONLY(2) NOT_AARCH64(4) == 0)

        tty->print("\n   + dump: ");

#ifdef AARCH64

      const char* reg_name = (i == trace_mh_nregs-1) ? "pc" : as_Register(i)->name();

#else

      const char* reg_name = trace_mh_regs[i]->name();

#endif

      tty->print(" %s: " INTPTR_FORMAT, reg_name, p2i((void *)saved_regs[i]));

    }

    tty->cr();