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 /*

  * Copyright (c) 1997, 2013, 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.

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  */

 #include "precompiled.hpp"

 #include "asm/macroAssembler.hpp"

 #include "interpreter/bytecodeHistogram.hpp"

 #include "interpreter/interpreter.hpp"

 #include "interpreter/interpreterGenerator.hpp"

 #include "interpreter/interpreterRuntime.hpp"

 #include "interpreter/templateTable.hpp"

 #include "oops/arrayOop.hpp"

 #include "oops/methodData.hpp"

 #include "oops/method.hpp"

 #include "oops/oop.inline.hpp"

 #include "prims/jvmtiExport.hpp"

 #include "prims/jvmtiThreadState.hpp"

 #include "runtime/arguments.hpp"

 #include "runtime/deoptimization.hpp"

 #include "runtime/frame.inline.hpp"

 #include "runtime/sharedRuntime.hpp"

 #include "runtime/stubRoutines.hpp"

 #include "runtime/synchronizer.hpp"

 #include "runtime/timer.hpp"

 #include "runtime/vframeArray.hpp"

 #include "utilities/debug.hpp"

 #include "utilities/macros.hpp"

 #ifndef CC_INTERP

 #ifndef FAST_DISPATCH

 #define FAST_DISPATCH 1

 #endif

 #undef FAST_DISPATCH

 // Generation of Interpreter

 //

 // The InterpreterGenerator generates the interpreter into Interpreter::_code.

 #define __ _masm->

 //----------------------------------------------------------------------------------------------------

 void InterpreterGenerator::save_native_result(void) {

   // result potentially in O0/O1: save it across calls

   const Address& l_tmp = InterpreterMacroAssembler::l_tmp;

   // result potentially in F0/F1: save it across calls

   const Address& d_tmp = InterpreterMacroAssembler::d_tmp;

   // save and restore any potential method result value around the unlocking operation

   __ stf(FloatRegisterImpl::D, F0, d_tmp);

 #ifdef _LP64

   __ stx(O0, l_tmp);

 #else

   __ std(O0, l_tmp);

 #endif

 }

 void InterpreterGenerator::restore_native_result(void) {

   const Address& l_tmp = InterpreterMacroAssembler::l_tmp;

   const Address& d_tmp = InterpreterMacroAssembler::d_tmp;

   // Restore any method result value

   __ ldf(FloatRegisterImpl::D, d_tmp, F0);

 #ifdef _LP64

   __ ldx(l_tmp, O0);

 #else

   __ ldd(l_tmp, O0);

 #endif

 }

 address TemplateInterpreterGenerator::generate_exception_handler_common(const char* name, const char* message, bool pass_oop) {

   assert(!pass_oop || message == NULL, "either oop or message but not both");

   address entry = __ pc();

   // expression stack must be empty before entering the VM if an exception happened

   __ empty_expression_stack();

   // load exception object

   __ set((intptr_t)name, G3_scratch);

   if (pass_oop) {

     __ call_VM(Oexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::create_klass_exception), G3_scratch, Otos_i);

   } else {

     __ set((intptr_t)message, G4_scratch);

     __ call_VM(Oexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::create_exception), G3_scratch, G4_scratch);

   }

   // throw exception

   assert(Interpreter::throw_exception_entry() != NULL, "generate it first");

   AddressLiteral thrower(Interpreter::throw_exception_entry());

   __ jump_to(thrower, G3_scratch);

   __ delayed()->nop();

   return entry;

 }

 address TemplateInterpreterGenerator::generate_ClassCastException_handler() {

   address entry = __ pc();

   // expression stack must be empty before entering the VM if an exception

   // happened

   __ empty_expression_stack();

   // load exception object

   __ call_VM(Oexception,

              CAST_FROM_FN_PTR(address,

                               InterpreterRuntime::throw_ClassCastException),

              Otos_i);

   __ should_not_reach_here();

   return entry;

 }

 address TemplateInterpreterGenerator::generate_ArrayIndexOutOfBounds_handler(const char* name) {

   address entry = __ pc();

   // expression stack must be empty before entering the VM if an exception happened

   __ empty_expression_stack();

   // convention: expect aberrant index in register G3_scratch, then shuffle the

   // index to G4_scratch for the VM call

   __ mov(G3_scratch, G4_scratch);

   __ set((intptr_t)name, G3_scratch);

   __ call_VM(Oexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::throw_ArrayIndexOutOfBoundsException), G3_scratch, G4_scratch);

   __ should_not_reach_here();

   return entry;

 }

 address TemplateInterpreterGenerator::generate_StackOverflowError_handler() {

   address entry = __ pc();

   // expression stack must be empty before entering the VM if an exception happened

   __ empty_expression_stack();

   __ call_VM(Oexception, CAST_FROM_FN_PTR(address, InterpreterRuntime::throw_StackOverflowError));

   __ should_not_reach_here();

   return entry;

 }

 address TemplateInterpreterGenerator::generate_return_entry_for(TosState state, int step, size_t index_size) {

   address entry = __ pc();

 #if !defined(_LP64) && defined(COMPILER2)

   // All return values are where we want them, except for Longs.  C2 returns

   // longs in G1 in the 32-bit build whereas the interpreter wants them in O0/O1.

   // Since the interpreter will return longs in G1 and O0/O1 in the 32bit

   // build even if we are returning from interpreted we just do a little

   // stupid shuffing.

   // Note: I tried to make c2 return longs in O0/O1 and G1 so we wouldn't have to

   // do this here. Unfortunately if we did a rethrow we'd see an machepilog node

   // first which would move g1 -> O0/O1 and destroy the exception we were throwing.

   if (state == ltos) {

     __ srl (G1,  0, O1);

     __ srlx(G1, 32, O0);

   }

 #endif // !_LP64 && COMPILER2

   // The callee returns with the stack possibly adjusted by adapter transition

   // We remove that possible adjustment here.

   // All interpreter local registers are untouched. Any result is passed back

   // in the O0/O1 or float registers. Before continuing, the arguments must be

   // popped from the java expression stack; i.e., Lesp must be adjusted.

   __ mov(Llast_SP, SP);   // Remove any adapter added stack space.

   const Register cache = G3_scratch;

   const Register index  = G1_scratch;

   __ get_cache_and_index_at_bcp(cache, index, 1, index_size);

   const Register flags = cache;

   __ ld_ptr(cache, ConstantPoolCache::base_offset() + ConstantPoolCacheEntry::flags_offset(), flags);

   const Register parameter_size = flags;

   __ and3(flags, ConstantPoolCacheEntry::parameter_size_mask, parameter_size);  // argument size in words

   __ sll(parameter_size, Interpreter::logStackElementSize, parameter_size);     // each argument size in bytes

   __ add(Lesp, parameter_size, Lesp);                                           // pop arguments

   __ dispatch_next(state, step);

   return entry;

 }

 address TemplateInterpreterGenerator::generate_deopt_entry_for(TosState state, int step) {

   address entry = __ pc();

   __ get_constant_pool_cache(LcpoolCache); // load LcpoolCache

   { Label L;

     Address exception_addr(G2_thread, Thread::pending_exception_offset());

     __ ld_ptr(exception_addr, Gtemp);  // Load pending exception.

     __ br_null_short(Gtemp, Assembler::pt, L);

     __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::throw_pending_exception));

     __ should_not_reach_here();

     __ bind(L);

   }

   __ dispatch_next(state, step);

   return entry;

 }

 // A result handler converts/unboxes a native call result into

 // a java interpreter/compiler result. The current frame is an

 // interpreter frame. The activation frame unwind code must be

 // consistent with that of TemplateTable::_return(...). In the

 // case of native methods, the caller's SP was not modified.

 address TemplateInterpreterGenerator::generate_result_handler_for(BasicType type) {

   address entry = __ pc();

   Register Itos_i  = Otos_i ->after_save();

   Register Itos_l  = Otos_l ->after_save();

   Register Itos_l1 = Otos_l1->after_save();

   Register Itos_l2 = Otos_l2->after_save();

   switch (type) {

     case T_BOOLEAN: __ subcc(G0, O0, G0); __ addc(G0, 0, Itos_i); break; // !0 => true; 0 => false

     case T_CHAR   : __ sll(O0, 16, O0); __ srl(O0, 16, Itos_i);   break; // cannot use and3, 0xFFFF too big as immediate value!

     case T_BYTE   : __ sll(O0, 24, O0); __ sra(O0, 24, Itos_i);   break;

     case T_SHORT  : __ sll(O0, 16, O0); __ sra(O0, 16, Itos_i);   break;

     case T_LONG   :

 #ifndef _LP64

                     __ mov(O1, Itos_l2);  // move other half of long

 #endif              // ifdef or no ifdef, fall through to the T_INT case

     case T_INT    : __ mov(O0, Itos_i);                         break;

     case T_VOID   : /* nothing to do */                         break;

     case T_FLOAT  : assert(F0 == Ftos_f, "fix this code" );     break;

     case T_DOUBLE : assert(F0 == Ftos_d, "fix this code" );     break;

     case T_OBJECT :

       __ ld_ptr(FP, (frame::interpreter_frame_oop_temp_offset*wordSize) + STACK_BIAS, Itos_i);

       __ verify_oop(Itos_i);

       break;

     default       : ShouldNotReachHere();

   }

   __ ret();                           // return from interpreter activation

   __ delayed()->restore(I5_savedSP, G0, SP);  // remove interpreter frame

   NOT_PRODUCT(__ emit_int32(0);)       // marker for disassembly

   return entry;

 }

 address TemplateInterpreterGenerator::generate_safept_entry_for(TosState state, address runtime_entry) {

   address entry = __ pc();

   __ push(state);

   __ call_VM(noreg, runtime_entry);

   __ dispatch_via(vtos, Interpreter::normal_table(vtos));

   return entry;

 }

 address TemplateInterpreterGenerator::generate_continuation_for(TosState state) {

   address entry = __ pc();

   __ dispatch_next(state);

   return entry;

 }

 //

 // Helpers for commoning out cases in the various type of method entries.

 //

 // increment invocation count & check for overflow

 //

 // Note: checking for negative value instead of overflow

 //       so we have a 'sticky' overflow test

 //

 // Lmethod: method

 // ??: invocation counter

 //

 void InterpreterGenerator::generate_counter_incr(Label* overflow, Label* profile_method, Label* profile_method_continue) {

   // Note: In tiered we increment either counters in MethodCounters* or in

   // MDO depending if we're profiling or not.

   const Register Rcounters = G3_scratch;

   Label done;

   if (TieredCompilation) {

     const int increment = InvocationCounter::count_increment;

     const int mask = ((1 << Tier0InvokeNotifyFreqLog) - 1) << InvocationCounter::count_shift;

     Label no_mdo;

     if (ProfileInterpreter) {

       // If no method data exists, go to profile_continue.

       __ ld_ptr(Lmethod, Method::method_data_offset(), G4_scratch);

       __ br_null_short(G4_scratch, Assembler::pn, no_mdo);

       // Increment counter

       Address mdo_invocation_counter(G4_scratch,

                                      in_bytes(MethodData::invocation_counter_offset()) +

                                      in_bytes(InvocationCounter::counter_offset()));

       __ increment_mask_and_jump(mdo_invocation_counter, increment, mask,

                                  G3_scratch, Lscratch,

                                  Assembler::zero, overflow);

       __ ba_short(done);

     }

     // Increment counter in MethodCounters*

     __ bind(no_mdo);

     Address invocation_counter(Rcounters,

             in_bytes(MethodCounters::invocation_counter_offset()) +

             in_bytes(InvocationCounter::counter_offset()));

     __ get_method_counters(Lmethod, Rcounters, done);

     __ increment_mask_and_jump(invocation_counter, increment, mask,

                                G4_scratch, Lscratch,

                                Assembler::zero, overflow);

     __ bind(done);

   } else {

     // Update standard invocation counters

     __ get_method_counters(Lmethod, Rcounters, done);

     __ increment_invocation_counter(Rcounters, O0, G4_scratch);

     if (ProfileInterpreter) {

       Address interpreter_invocation_counter(Rcounters,

             in_bytes(MethodCounters::interpreter_invocation_counter_offset()));

       __ ld(interpreter_invocation_counter, G4_scratch);

       __ inc(G4_scratch);

       __ st(G4_scratch, interpreter_invocation_counter);

     }

     if (ProfileInterpreter && profile_method != NULL) {

       // Test to see if we should create a method data oop

       AddressLiteral profile_limit((address)&InvocationCounter::InterpreterProfileLimit);

       __ load_contents(profile_limit, G3_scratch);

       __ cmp_and_br_short(O0, G3_scratch, Assembler::lessUnsigned, Assembler::pn, *profile_method_continue);

       // if no method data exists, go to profile_method

       __ test_method_data_pointer(*profile_method);

     }

     AddressLiteral invocation_limit((address)&InvocationCounter::InterpreterInvocationLimit);

     __ load_contents(invocation_limit, G3_scratch);

     __ cmp(O0, G3_scratch);

     __ br(Assembler::greaterEqualUnsigned, false, Assembler::pn, *overflow); // Far distance

     __ delayed()->nop();

     __ bind(done);

   }

 }

 // Allocate monitor and lock method (asm interpreter)

 // ebx - Method*

 //

 void InterpreterGenerator::lock_method(void) {

   __ ld(Lmethod, in_bytes(Method::access_flags_offset()), O0);  // Load access flags.

 #ifdef ASSERT

  { Label ok;

    __ btst(JVM_ACC_SYNCHRONIZED, O0);

    __ br( Assembler::notZero, false, Assembler::pt, ok);

    __ delayed()->nop();

    __ stop("method doesn't need synchronization");

    __ bind(ok);

   }

 #endif // ASSERT

   // get synchronization object to O0

   { Label done;

     const int mirror_offset = in_bytes(Klass::java_mirror_offset());

     __ btst(JVM_ACC_STATIC, O0);

     __ br( Assembler::zero, true, Assembler::pt, done);

     __ delayed()->ld_ptr(Llocals, Interpreter::local_offset_in_bytes(0), O0); // get receiver for not-static case

     __ ld_ptr( Lmethod, in_bytes(Method::const_offset()), O0);

     __ ld_ptr( O0, in_bytes(ConstMethod::constants_offset()), O0);

     __ ld_ptr( O0, ConstantPool::pool_holder_offset_in_bytes(), O0);

     // lock the mirror, not the Klass*

     __ ld_ptr( O0, mirror_offset, O0);

 #ifdef ASSERT

     __ tst(O0);

     __ breakpoint_trap(Assembler::zero, Assembler::ptr_cc);

 #endif // ASSERT

     __ bind(done);

   }

   __ add_monitor_to_stack(true, noreg, noreg);  // allocate monitor elem

   __ st_ptr( O0, Lmonitors, BasicObjectLock::obj_offset_in_bytes());   // store object

   // __ untested("lock_object from method entry");

   __ lock_object(Lmonitors, O0);

 }

 void TemplateInterpreterGenerator::generate_stack_overflow_check(Register Rframe_size,

                                                          Register Rscratch,

                                                          Register Rscratch2) {

   const int page_size = os::vm_page_size();

   Label after_frame_check;

   assert_different_registers(Rframe_size, Rscratch, Rscratch2);

   __ set(page_size, Rscratch);

   __ cmp_and_br_short(Rframe_size, Rscratch, Assembler::lessEqual, Assembler::pt, after_frame_check);

   // get the stack base, and in debug, verify it is non-zero

   __ ld_ptr( G2_thread, Thread::stack_base_offset(), Rscratch );

 #ifdef ASSERT

   Label base_not_zero;

   __ br_notnull_short(Rscratch, Assembler::pn, base_not_zero);

   __ stop("stack base is zero in generate_stack_overflow_check");

   __ bind(base_not_zero);

 #endif

   // get the stack size, and in debug, verify it is non-zero

   assert( sizeof(size_t) == sizeof(intptr_t), "wrong load size" );

   __ ld_ptr( G2_thread, Thread::stack_size_offset(), Rscratch2 );

 #ifdef ASSERT

   Label size_not_zero;

   __ br_notnull_short(Rscratch2, Assembler::pn, size_not_zero);

   __ stop("stack size is zero in generate_stack_overflow_check");

   __ bind(size_not_zero);

 #endif

   // compute the beginning of the protected zone minus the requested frame size

   __ sub( Rscratch, Rscratch2,   Rscratch );

   __ set( (StackRedPages+StackYellowPages) * page_size, Rscratch2 );

   __ add( Rscratch, Rscratch2,   Rscratch );

   // Add in the size of the frame (which is the same as subtracting it from the

   // SP, which would take another register

   __ add( Rscratch, Rframe_size, Rscratch );

   // the frame is greater than one page in size, so check against

   // the bottom of the stack

   __ cmp_and_brx_short(SP, Rscratch, Assembler::greaterUnsigned, Assembler::pt, after_frame_check);

   // the stack will overflow, throw an exception

   // Note that SP is restored to sender's sp (in the delay slot). This

   // is necessary if the sender's frame is an extended compiled frame

   // (see gen_c2i_adapter()) and safer anyway in case of JSR292

   // adaptations.

   // Note also that the restored frame is not necessarily interpreted.

   // Use the shared runtime version of the StackOverflowError.

   assert(StubRoutines::throw_StackOverflowError_entry() != NULL, "stub not yet generated");

   AddressLiteral stub(StubRoutines::throw_StackOverflowError_entry());

   __ jump_to(stub, Rscratch);

   __ delayed()->mov(O5_savedSP, SP);

   // if you get to here, then there is enough stack space

   __ bind( after_frame_check );

 }

 //

 // Generate a fixed interpreter frame. This is identical setup for interpreted

 // methods and for native methods hence the shared code.

 void TemplateInterpreterGenerator::generate_fixed_frame(bool native_call) {

   //

   //

   // The entry code sets up a new interpreter frame in 4 steps:

   //

   // 1) Increase caller's SP by for the extra local space needed:

   //    (check for overflow)

   //    Efficient implementation of xload/xstore bytecodes requires

   //    that arguments and non-argument locals are in a contigously

   //    addressable memory block => non-argument locals must be

   //    allocated in the caller's frame.

   //

   // 2) Create a new stack frame and register window:

   //    The new stack frame must provide space for the standard

   //    register save area, the maximum java expression stack size,

   //    the monitor slots (0 slots initially), and some frame local

   //    scratch locations.

   //

   // 3) The following interpreter activation registers must be setup:

   //    Lesp       : expression stack pointer

   //    Lbcp       : bytecode pointer

   //    Lmethod    : method

   //    Llocals    : locals pointer

   //    Lmonitors  : monitor pointer

   //    LcpoolCache: constant pool cache

   //

   // 4) Initialize the non-argument locals if necessary:

   //    Non-argument locals may need to be initialized to NULL

   //    for GC to work. If the oop-map information is accurate

   //    (in the absence of the JSR problem), no initialization

   //    is necessary.

   //

   // (gri - 2/25/2000)

   int rounded_vm_local_words = round_to( frame::interpreter_frame_vm_local_words, WordsPerLong );

   const int extra_space =

     rounded_vm_local_words +                   // frame local scratch space

     Method::extra_stack_entries() +            // extra stack for jsr 292

     frame::memory_parameter_word_sp_offset +   // register save area

     (native_call ? frame::interpreter_frame_extra_outgoing_argument_words : 0);

   const Register Glocals_size = G3;

   const Register RconstMethod = Glocals_size;

   const Register Otmp1 = O3;

   const Register Otmp2 = O4;

   // Lscratch can't be used as a temporary because the call_stub uses

   // it to assert that the stack frame was setup correctly.

   const Address constMethod       (G5_method, Method::const_offset());

   const Address size_of_parameters(RconstMethod, ConstMethod::size_of_parameters_offset());

   __ ld_ptr( constMethod, RconstMethod );

   __ lduh( size_of_parameters, Glocals_size);

   // Gargs points to first local + BytesPerWord

   // Set the saved SP after the register window save

   //

   assert_different_registers(Gargs, Glocals_size, Gframe_size, O5_savedSP);

   __ sll(Glocals_size, Interpreter::logStackElementSize, Otmp1);

   __ add(Gargs, Otmp1, Gargs);

   if (native_call) {

     __ calc_mem_param_words( Glocals_size, Gframe_size );

     __ add( Gframe_size,  extra_space, Gframe_size);

     __ round_to( Gframe_size, WordsPerLong );

     __ sll( Gframe_size, LogBytesPerWord, Gframe_size );

   } else {

     //

     // Compute number of locals in method apart from incoming parameters

     //

     const Address size_of_locals    (Otmp1, ConstMethod::size_of_locals_offset());

     __ ld_ptr( constMethod, Otmp1 );

     __ lduh( size_of_locals, Otmp1 );

     __ sub( Otmp1, Glocals_size, Glocals_size );

     __ round_to( Glocals_size, WordsPerLong );

     __ sll( Glocals_size, Interpreter::logStackElementSize, Glocals_size );

     // see if the frame is greater than one page in size. If so,

     // then we need to verify there is enough stack space remaining

     // Frame_size = (max_stack + extra_space) * BytesPerWord;

     __ ld_ptr( constMethod, Gframe_size );

     __ lduh( Gframe_size, in_bytes(ConstMethod::max_stack_offset()), Gframe_size );

     __ add( Gframe_size, extra_space, Gframe_size );

     __ round_to( Gframe_size, WordsPerLong );

     __ sll( Gframe_size, Interpreter::logStackElementSize, Gframe_size);

     // Add in java locals size for stack overflow check only

     __ add( Gframe_size, Glocals_size, Gframe_size );

     const Register Otmp2 = O4;

     assert_different_registers(Otmp1, Otmp2, O5_savedSP);

     generate_stack_overflow_check(Gframe_size, Otmp1, Otmp2);

     __ sub( Gframe_size, Glocals_size, Gframe_size);

     //

     // bump SP to accomodate the extra locals

     //

     __ sub( SP, Glocals_size, SP );

   }

   //

   // now set up a stack frame with the size computed above

   //

   __ neg( Gframe_size );

   __ save( SP, Gframe_size, SP );

   //

   // now set up all the local cache registers

   //

   // NOTE: At this point, Lbyte_code/Lscratch has been modified. Note

   // that all present references to Lbyte_code initialize the register

   // immediately before use

   if (native_call) {

     __ mov(G0, Lbcp);

   } else {

     __ ld_ptr(G5_method, Method::const_offset(), Lbcp);

     __ add(Lbcp, in_bytes(ConstMethod::codes_offset()), Lbcp);

   }

   __ mov( G5_method, Lmethod);                 // set Lmethod

   __ get_constant_pool_cache( LcpoolCache );   // set LcpoolCache

   __ sub(FP, rounded_vm_local_words * BytesPerWord, Lmonitors ); // set Lmonitors

 #ifdef _LP64

   __ add( Lmonitors, STACK_BIAS, Lmonitors );   // Account for 64 bit stack bias

 #endif

   __ sub(Lmonitors, BytesPerWord, Lesp);       // set Lesp

   // setup interpreter activation registers

   __ sub(Gargs, BytesPerWord, Llocals);        // set Llocals

   if (ProfileInterpreter) {

 #ifdef FAST_DISPATCH

     // FAST_DISPATCH and ProfileInterpreter are mutually exclusive since

     // they both use I2.

     assert(0, "FAST_DISPATCH and +ProfileInterpreter are mutually exclusive");

 #endif // FAST_DISPATCH

     __ set_method_data_pointer();

   }

 }

 // Empty method, generate a very fast return.

 address InterpreterGenerator::generate_empty_entry(void) {

   // A method that does nother but return...

   address entry = __ pc();

   Label slow_path;

   // do nothing for empty methods (do not even increment invocation counter)

   if ( UseFastEmptyMethods) {

     // If we need a safepoint check, generate full interpreter entry.

     AddressLiteral sync_state(SafepointSynchronize::address_of_state());

     __ set(sync_state, G3_scratch);

     __ cmp_and_br_short(G3_scratch, SafepointSynchronize::_not_synchronized, Assembler::notEqual, Assembler::pn, slow_path);

     // Code: _return

     __ retl();

     __ delayed()->mov(O5_savedSP, SP);

     __ bind(slow_path);

     (void) generate_normal_entry(false);

     return entry;

   }

   return NULL;

 }

 // Call an accessor method (assuming it is resolved, otherwise drop into

 // vanilla (slow path) entry

 // Generates code to elide accessor methods

 // Uses G3_scratch and G1_scratch as scratch

 address InterpreterGenerator::generate_accessor_entry(void) {

   // Code: _aload_0, _(i|a)getfield, _(i|a)return or any rewrites thereof;

   // parameter size = 1

   // Note: We can only use this code if the getfield has been resolved

   //       and if we don't have a null-pointer exception => check for

   //       these conditions first and use slow path if necessary.

   address entry = __ pc();

   Label slow_path;

   // XXX: for compressed oops pointer loading and decoding doesn't fit in

   // delay slot and damages G1

   if ( UseFastAccessorMethods && !UseCompressedOops ) {

     // Check if we need to reach a safepoint and generate full interpreter

     // frame if so.

     AddressLiteral sync_state(SafepointSynchronize::address_of_state());

     __ load_contents(sync_state, G3_scratch);

     __ cmp(G3_scratch, SafepointSynchronize::_not_synchronized);

     __ cmp_and_br_short(G3_scratch, SafepointSynchronize::_not_synchronized, Assembler::notEqual, Assembler::pn, slow_path);

     // Check if local 0 != NULL

     __ ld_ptr(Gargs, G0, Otos_i ); // get local 0

     // check if local 0 == NULL and go the slow path

     __ br_null_short(Otos_i, Assembler::pn, slow_path);

     // read first instruction word and extract bytecode @ 1 and index @ 2

     // get first 4 bytes of the bytecodes (big endian!)

     __ ld_ptr(G5_method, Method::const_offset(), G1_scratch);

     __ ld(G1_scratch, ConstMethod::codes_offset(), G1_scratch);

     // move index @ 2 far left then to the right most two bytes.

     __ sll(G1_scratch, 2*BitsPerByte, G1_scratch);

     __ srl(G1_scratch, 2*BitsPerByte - exact_log2(in_words(

                       ConstantPoolCacheEntry::size()) * BytesPerWord), G1_scratch);

     // get constant pool cache

     __ ld_ptr(G5_method, Method::const_offset(), G3_scratch);

     __ ld_ptr(G3_scratch, ConstMethod::constants_offset(), G3_scratch);

     __ ld_ptr(G3_scratch, ConstantPool::cache_offset_in_bytes(), G3_scratch);

     // get specific constant pool cache entry

     __ add(G3_scratch, G1_scratch, G3_scratch);

     // Check the constant Pool cache entry to see if it has been resolved.

     // If not, need the slow path.

     ByteSize cp_base_offset = ConstantPoolCache::base_offset();

     __ ld_ptr(G3_scratch, cp_base_offset + ConstantPoolCacheEntry::indices_offset(), G1_scratch);

     __ srl(G1_scratch, 2*BitsPerByte, G1_scratch);

     __ and3(G1_scratch, 0xFF, G1_scratch);

     __ cmp_and_br_short(G1_scratch, Bytecodes::_getfield, Assembler::notEqual, Assembler::pn, slow_path);

     // Get the type and return field offset from the constant pool cache

     __ ld_ptr(G3_scratch, cp_base_offset + ConstantPoolCacheEntry::flags_offset(), G1_scratch);

     __ ld_ptr(G3_scratch, cp_base_offset + ConstantPoolCacheEntry::f2_offset(), G3_scratch);

     Label xreturn_path;

     // Need to differentiate between igetfield, agetfield, bgetfield etc.

     // because they are different sizes.

     // Get the type from the constant pool cache

     __ srl(G1_scratch, ConstantPoolCacheEntry::tos_state_shift, G1_scratch);

     // Make sure we don't need to mask G1_scratch after the above shift

     ConstantPoolCacheEntry::verify_tos_state_shift();

     __ cmp(G1_scratch, atos );

     __ br(Assembler::equal, true, Assembler::pt, xreturn_path);

     __ delayed()->ld_ptr(Otos_i, G3_scratch, Otos_i);

     __ cmp(G1_scratch, itos);

     __ br(Assembler::equal, true, Assembler::pt, xreturn_path);

     __ delayed()->ld(Otos_i, G3_scratch, Otos_i);

     __ cmp(G1_scratch, stos);

     __ br(Assembler::equal, true, Assembler::pt, xreturn_path);

     __ delayed()->ldsh(Otos_i, G3_scratch, Otos_i);

     __ cmp(G1_scratch, ctos);

     __ br(Assembler::equal, true, Assembler::pt, xreturn_path);

     __ delayed()->lduh(Otos_i, G3_scratch, Otos_i);

 #ifdef ASSERT

     __ cmp(G1_scratch, btos);

     __ br(Assembler::equal, true, Assembler::pt, xreturn_path);

     __ delayed()->ldsb(Otos_i, G3_scratch, Otos_i);

     __ should_not_reach_here();

 #endif

     __ ldsb(Otos_i, G3_scratch, Otos_i);

     __ bind(xreturn_path);

     // _ireturn/_areturn

     __ retl();                      // return from leaf routine

     __ delayed()->mov(O5_savedSP, SP);

     // Generate regular method entry

     __ bind(slow_path);

     (void) generate_normal_entry(false);

     return entry;

   }

   return NULL;

 }

 // Method entry for java.lang.ref.Reference.get.

 address InterpreterGenerator::generate_Reference_get_entry(void) {

 #if INCLUDE_ALL_GCS

   // Code: _aload_0, _getfield, _areturn

   // parameter size = 1

   //

   // The code that gets generated by this routine is split into 2 parts:

   //    1. The "intrinsified" code for G1 (or any SATB based GC),

   //    2. The slow path - which is an expansion of the regular method entry.

   //

   // Notes:-

   // * In the G1 code we do not check whether we need to block for

   //   a safepoint. If G1 is enabled then we must execute the specialized

   //   code for Reference.get (except when the Reference object is null)

   //   so that we can log the value in the referent field with an SATB

   //   update buffer.

   //   If the code for the getfield template is modified so that the

   //   G1 pre-barrier code is executed when the current method is

   //   Reference.get() then going through the normal method entry

   //   will be fine.

   // * The G1 code can, however, check the receiver object (the instance

   //   of java.lang.Reference) and jump to the slow path if null. If the

   //   Reference object is null then we obviously cannot fetch the referent

   //   and so we don't need to call the G1 pre-barrier. Thus we can use the

   //   regular method entry code to generate the NPE.

   //

   // This code is based on generate_accessor_enty.

   address entry = __ pc();

   const int referent_offset = java_lang_ref_Reference::referent_offset;

   guarantee(referent_offset > 0, "referent offset not initialized");

   if (UseG1GC) {

      Label slow_path;

     // In the G1 code we don't check if we need to reach a safepoint. We

     // continue and the thread will safepoint at the next bytecode dispatch.

     // Check if local 0 != NULL

     // If the receiver is null then it is OK to jump to the slow path.

     __ ld_ptr(Gargs, G0, Otos_i ); // get local 0

     // check if local 0 == NULL and go the slow path

     __ cmp_and_brx_short(Otos_i, 0, Assembler::equal, Assembler::pn, slow_path);

     // Load the value of the referent field.

     if (Assembler::is_simm13(referent_offset)) {

       __ load_heap_oop(Otos_i, referent_offset, Otos_i);

     } else {

       __ set(referent_offset, G3_scratch);

       __ load_heap_oop(Otos_i, G3_scratch, Otos_i);

     }

     // Generate the G1 pre-barrier code to log the value of

     // the referent field in an SATB buffer. Note with

     // these parameters the pre-barrier does not generate

     // the load of the previous value

     __ g1_write_barrier_pre(noreg /* obj */, noreg /* index */, 0 /* offset */,

                             Otos_i /* pre_val */,

                             G3_scratch /* tmp */,

                             true /* preserve_o_regs */);

     // _areturn

     __ retl();                      // return from leaf routine

     __ delayed()->mov(O5_savedSP, SP);

     // Generate regular method entry

     __ bind(slow_path);

     (void) generate_normal_entry(false);

     return entry;

   }

 #endif // INCLUDE_ALL_GCS

   // If G1 is not enabled then attempt to go through the accessor entry point

   // Reference.get is an accessor

   return generate_accessor_entry();

 }

 //

 // Interpreter stub for calling a native method. (asm interpreter)

 // This sets up a somewhat different looking stack for calling the native method

 // than the typical interpreter frame setup.

 //

 address InterpreterGenerator::generate_native_entry(bool synchronized) {

   address entry = __ pc();

   // the following temporary registers are used during frame creation

   const Register Gtmp1 = G3_scratch ;

   const Register Gtmp2 = G1_scratch;

   bool inc_counter  = UseCompiler || CountCompiledCalls;

   // make sure registers are different!

   assert_different_registers(G2_thread, G5_method, Gargs, Gtmp1, Gtmp2);

   const Address Laccess_flags(Lmethod, Method::access_flags_offset());

   const Register Glocals_size = G3;

   assert_different_registers(Glocals_size, G4_scratch, Gframe_size);

   // make sure method is native & not abstract

   // rethink these assertions - they can be simplified and shared (gri 2/25/2000)

 #ifdef ASSERT

   __ ld(G5_method, Method::access_flags_offset(), Gtmp1);

   {

     Label L;

     __ btst(JVM_ACC_NATIVE, Gtmp1);

     __ br(Assembler::notZero, false, Assembler::pt, L);

     __ delayed()->nop();

     __ stop("tried to execute non-native method as native");

     __ bind(L);

   }

   { Label L;

     __ btst(JVM_ACC_ABSTRACT, Gtmp1);

     __ br(Assembler::zero, false, Assembler::pt, L);

     __ delayed()->nop();

     __ stop("tried to execute abstract method as non-abstract");

     __ bind(L);

   }

 #endif // ASSERT

  // generate the code to allocate the interpreter stack frame

   generate_fixed_frame(true);

   //

   // No locals to initialize for native method

   //

   // this slot will be set later, we initialize it to null here just in

   // case we get a GC before the actual value is stored later

   __ st_ptr(G0, FP, (frame::interpreter_frame_oop_temp_offset * wordSize) + STACK_BIAS);

   const Address do_not_unlock_if_synchronized(G2_thread,

     JavaThread::do_not_unlock_if_synchronized_offset());

   // Since at this point in the method invocation the exception handler

   // would try to exit the monitor of synchronized methods which hasn't

   // been entered yet, we set the thread local variable

   // _do_not_unlock_if_synchronized to true. If any exception was thrown by

   // runtime, exception handling i.e. unlock_if_synchronized_method will

   // check this thread local flag.

   // This flag has two effects, one is to force an unwind in the topmost

   // interpreter frame and not perform an unlock while doing so.

   __ movbool(true, G3_scratch);

   __ stbool(G3_scratch, do_not_unlock_if_synchronized);

   // increment invocation counter and check for overflow

   //

   // Note: checking for negative value instead of overflow

   //       so we have a 'sticky' overflow test (may be of

   //       importance as soon as we have true MT/MP)

   Label invocation_counter_overflow;

   Label Lcontinue;

   if (inc_counter) {

     generate_counter_incr(&invocation_counter_overflow, NULL, NULL);

   }

   __ bind(Lcontinue);

   bang_stack_shadow_pages(true);

   // reset the _do_not_unlock_if_synchronized flag

   __ stbool(G0, do_not_unlock_if_synchronized);

   // check for synchronized methods

   // Must happen AFTER invocation_counter check and stack overflow check,

   // so method is not locked if overflows.

   if (synchronized) {

     lock_method();

   } else {

 #ifdef ASSERT

     { Label ok;

       __ ld(Laccess_flags, O0);

       __ btst(JVM_ACC_SYNCHRONIZED, O0);

       __ br( Assembler::zero, false, Assembler::pt, ok);

       __ delayed()->nop();

       __ stop("method needs synchronization");

       __ bind(ok);

     }

 #endif // ASSERT

   }

   // start execution

   __ verify_thread();

   // JVMTI support

   __ notify_method_entry();

   // native call

   // (note that O0 is never an oop--at most it is a handle)

   // It is important not to smash any handles created by this call,

   // until any oop handle in O0 is dereferenced.

   // (note that the space for outgoing params is preallocated)

   // get signature handler

   { Label L;

     Address signature_handler(Lmethod, Method::signature_handler_offset());

     __ ld_ptr(signature_handler, G3_scratch);

     __ br_notnull_short(G3_scratch, Assembler::pt, L);

     __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::prepare_native_call), Lmethod);

     __ ld_ptr(signature_handler, G3_scratch);

     __ bind(L);

   }

   // Push a new frame so that the args will really be stored in

   // Copy a few locals across so the new frame has the variables

   // we need but these values will be dead at the jni call and

   // therefore not gc volatile like the values in the current

   // frame (Lmethod in particular)

   // Flush the method pointer to the register save area

   __ st_ptr(Lmethod, SP, (Lmethod->sp_offset_in_saved_window() * wordSize) + STACK_BIAS);

   __ mov(Llocals, O1);

   // calculate where the mirror handle body is allocated in the interpreter frame:

   __ add(FP, (frame::interpreter_frame_oop_temp_offset * wordSize) + STACK_BIAS, O2);

   // Calculate current frame size

   __ sub(SP, FP, O3);         // Calculate negative of current frame size

   __ save(SP, O3, SP);        // Allocate an identical sized frame

   // Note I7 has leftover trash. Slow signature handler will fill it in

   // should we get there. Normal jni call will set reasonable last_Java_pc

   // below (and fix I7 so the stack trace doesn't have a meaningless frame

   // in it).

   // Load interpreter frame's Lmethod into same register here

   __ ld_ptr(FP, (Lmethod->sp_offset_in_saved_window() * wordSize) + STACK_BIAS, Lmethod);

   __ mov(I1, Llocals);

   __ mov(I2, Lscratch2);     // save the address of the mirror

   // ONLY Lmethod and Llocals are valid here!

   // call signature handler, It will move the arg properly since Llocals in current frame

   // matches that in outer frame

   __ callr(G3_scratch, 0);

   __ delayed()->nop();

   // Result handler is in Lscratch

   // Reload interpreter frame's Lmethod since slow signature handler may block

   __ ld_ptr(FP, (Lmethod->sp_offset_in_saved_window() * wordSize) + STACK_BIAS, Lmethod);

   { Label not_static;

     __ ld(Laccess_flags, O0);

     __ btst(JVM_ACC_STATIC, O0);

     __ br( Assembler::zero, false, Assembler::pt, not_static);

     // get native function entry point(O0 is a good temp until the very end)

     __ delayed()->ld_ptr(Lmethod, in_bytes(Method::native_function_offset()), O0);

     // for static methods insert the mirror argument

     const int mirror_offset = in_bytes(Klass::java_mirror_offset());

     __ ld_ptr(Lmethod, Method:: const_offset(), O1);

     __ ld_ptr(O1, ConstMethod::constants_offset(), O1);

     __ ld_ptr(O1, ConstantPool::pool_holder_offset_in_bytes(), O1);

     __ ld_ptr(O1, mirror_offset, O1);

 #ifdef ASSERT

     if (!PrintSignatureHandlers)  // do not dirty the output with this

     { Label L;

       __ br_notnull_short(O1, Assembler::pt, L);

       __ stop("mirror is missing");

       __ bind(L);

     }

 #endif // ASSERT

     __ st_ptr(O1, Lscratch2, 0);

     __ mov(Lscratch2, O1);

     __ bind(not_static);

   }

   // At this point, arguments have been copied off of stack into

   // their JNI positions, which are O1..O5 and SP[68..].

   // Oops are boxed in-place on the stack, with handles copied to arguments.

   // The result handler is in Lscratch.  O0 will shortly hold the JNIEnv*.

 #ifdef ASSERT

   { Label L;

     __ br_notnull_short(O0, Assembler::pt, L);

     __ stop("native entry point is missing");

     __ bind(L);

   }

 #endif // ASSERT

   //

   // setup the frame anchor

   //

   // The scavenge function only needs to know that the PC of this frame is

   // in the interpreter method entry code, it doesn't need to know the exact

   // PC and hence we can use O7 which points to the return address from the

   // previous call in the code stream (signature handler function)

   //

   // The other trick is we set last_Java_sp to FP instead of the usual SP because

   // we have pushed the extra frame in order to protect the volatile register(s)

   // in that frame when we return from the jni call

   //

   __ set_last_Java_frame(FP, O7);

   __ mov(O7, I7);  // make dummy interpreter frame look like one above,

                    // not meaningless information that'll confuse me.

   // flush the windows now. We don't care about the current (protection) frame

   // only the outer frames

   __ flushw();

   // mark windows as flushed

   Address flags(G2_thread, JavaThread::frame_anchor_offset() + JavaFrameAnchor::flags_offset());

   __ set(JavaFrameAnchor::flushed, G3_scratch);

   __ st(G3_scratch, flags);

   // Transition from _thread_in_Java to _thread_in_native. We are already safepoint ready.

   Address thread_state(G2_thread, JavaThread::thread_state_offset());

 #ifdef ASSERT

   { Label L;

     __ ld(thread_state, G3_scratch);

     __ cmp_and_br_short(G3_scratch, _thread_in_Java, Assembler::equal, Assembler::pt, L);

     __ stop("Wrong thread state in native stub");

     __ bind(L);

   }

 #endif // ASSERT

   __ set(_thread_in_native, G3_scratch);

   __ st(G3_scratch, thread_state);

   // Call the jni method, using the delay slot to set the JNIEnv* argument.

   __ save_thread(L7_thread_cache); // save Gthread

   __ callr(O0, 0);

   __ delayed()->

      add(L7_thread_cache, in_bytes(JavaThread::jni_environment_offset()), O0);

   // Back from jni method Lmethod in this frame is DEAD, DEAD, DEAD

   __ restore_thread(L7_thread_cache); // restore G2_thread

   __ reinit_heapbase();

   // must we block?

   // Block, if necessary, before resuming in _thread_in_Java state.

   // In order for GC to work, don't clear the last_Java_sp until after blocking.

   { Label no_block;

     AddressLiteral sync_state(SafepointSynchronize::address_of_state());

     // Switch thread to "native transition" state before reading the synchronization state.

     // This additional state is necessary because reading and testing the synchronization

     // state is not atomic w.r.t. GC, as this scenario demonstrates:

     //     Java thread A, in _thread_in_native state, loads _not_synchronized and is preempted.

     //     VM thread changes sync state to synchronizing and suspends threads for GC.

     //     Thread A is resumed to finish this native method, but doesn't block here since it

     //     didn't see any synchronization is progress, and escapes.

     __ set(_thread_in_native_trans, G3_scratch);

     __ st(G3_scratch, thread_state);

     if(os::is_MP()) {

       if (UseMembar) {

         // Force this write out before the read below

         __ membar(Assembler::StoreLoad);

       } else {

         // Write serialization page so VM thread can do a pseudo remote membar.

         // We use the current thread pointer to calculate a thread specific

         // offset to write to within the page. This minimizes bus traffic

         // due to cache line collision.

         __ serialize_memory(G2_thread, G1_scratch, G3_scratch);

       }

     }

     __ load_contents(sync_state, G3_scratch);

     __ cmp(G3_scratch, SafepointSynchronize::_not_synchronized);

     Label L;

     __ br(Assembler::notEqual, false, Assembler::pn, L);

     __ delayed()->ld(G2_thread, JavaThread::suspend_flags_offset(), G3_scratch);

     __ cmp_and_br_short(G3_scratch, 0, Assembler::equal, Assembler::pt, no_block);

     __ bind(L);

     // Block.  Save any potential method result value before the operation and

     // use a leaf call to leave the last_Java_frame setup undisturbed.

     save_native_result();

     __ call_VM_leaf(L7_thread_cache,

                     CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans),

                     G2_thread);

     // Restore any method result value

     restore_native_result();

     __ bind(no_block);

   }

   // Clear the frame anchor now

   __ reset_last_Java_frame();

   // Move the result handler address

   __ mov(Lscratch, G3_scratch);

   // return possible result to the outer frame

 #ifndef __LP64

   __ mov(O0, I0);

   __ restore(O1, G0, O1);

 #else

   __ restore(O0, G0, O0);

 #endif /* __LP64 */

   // Move result handler to expected register

   __ mov(G3_scratch, Lscratch);

   // Back in normal (native) interpreter frame. State is thread_in_native_trans

   // switch to thread_in_Java.

   __ set(_thread_in_Java, G3_scratch);

   __ st(G3_scratch, thread_state);

   // reset handle block

   __ ld_ptr(G2_thread, JavaThread::active_handles_offset(), G3_scratch);

   __ st_ptr(G0, G3_scratch, JNIHandleBlock::top_offset_in_bytes());

   // If we have an oop result store it where it will be safe for any further gc

   // until we return now that we've released the handle it might be protected by

   {

     Label no_oop, store_result;

     __ set((intptr_t)AbstractInterpreter::result_handler(T_OBJECT), G3_scratch);

     __ cmp_and_brx_short(G3_scratch, Lscratch, Assembler::notEqual, Assembler::pt, no_oop);

     __ addcc(G0, O0, O0);

     __ brx(Assembler::notZero, true, Assembler::pt, store_result);     // if result is not NULL:

     __ delayed()->ld_ptr(O0, 0, O0);                                   // unbox it

     __ mov(G0, O0);

     __ bind(store_result);

     // Store it where gc will look for it and result handler expects it.

     __ st_ptr(O0, FP, (frame::interpreter_frame_oop_temp_offset*wordSize) + STACK_BIAS);

     __ bind(no_oop);

   }

   // handle exceptions (exception handling will handle unlocking!)

   { Label L;

     Address exception_addr(G2_thread, Thread::pending_exception_offset());

     __ ld_ptr(exception_addr, Gtemp);

     __ br_null_short(Gtemp, Assembler::pt, L);

     // Note: This could be handled more efficiently since we know that the native

     //       method doesn't have an exception handler. We could directly return

     //       to the exception handler for the caller.

     __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::throw_pending_exception));

     __ should_not_reach_here();

     __ bind(L);

   }

   // JVMTI support (preserves thread register)

   __ notify_method_exit(true, ilgl, InterpreterMacroAssembler::NotifyJVMTI);

   if (synchronized) {

     // save and restore any potential method result value around the unlocking operation

     save_native_result();

     __ add( __ top_most_monitor(), O1);

     __ unlock_object(O1);

     restore_native_result();

   }

 #if defined(COMPILER2) && !defined(_LP64)

   // C2 expects long results in G1 we can't tell if we're returning to interpreted

   // or compiled so just be safe.

   __ sllx(O0, 32, G1);          // Shift bits into high G1

   __ srl (O1, 0, O1);           // Zero extend O1

   __ or3 (O1, G1, G1);          // OR 64 bits into G1

 #endif /* COMPILER2 && !_LP64 */

   // dispose of return address and remove activation

 #ifdef ASSERT

   {

     Label ok;

     __ cmp_and_brx_short(I5_savedSP, FP, Assembler::greaterEqualUnsigned, Assembler::pt, ok);

     __ stop("bad I5_savedSP value");

     __ should_not_reach_here();

     __ bind(ok);

   }

 #endif

   if (TraceJumps) {

     // Move target to register that is recordable

     __ mov(Lscratch, G3_scratch);

     __ JMP(G3_scratch, 0);

   } else {

     __ jmp(Lscratch, 0);

   }

   __ delayed()->nop();

   if (inc_counter) {

     // handle invocation counter overflow

     __ bind(invocation_counter_overflow);

     generate_counter_overflow(Lcontinue);

   }

   return entry;

 }

 // Generic method entry to (asm) interpreter

 //------------------------------------------------------------------------------------------------------------------------

 //

 address InterpreterGenerator::generate_normal_entry(bool synchronized) {

   address entry = __ pc();

   bool inc_counter  = UseCompiler || CountCompiledCalls;

   // the following temporary registers are used during frame creation

   const Register Gtmp1 = G3_scratch ;

   const Register Gtmp2 = G1_scratch;

   // make sure registers are different!

   assert_different_registers(G2_thread, G5_method, Gargs, Gtmp1, Gtmp2);

   const Address constMethod       (G5_method, Method::const_offset());

   // Seems like G5_method is live at the point this is used. So we could make this look consistent

   // and use in the asserts.

   const Address access_flags      (Lmethod,   Method::access_flags_offset());

   const Register Glocals_size = G3;

   assert_different_registers(Glocals_size, G4_scratch, Gframe_size);

   // make sure method is not native & not abstract

   // rethink these assertions - they can be simplified and shared (gri 2/25/2000)

 #ifdef ASSERT

   __ ld(G5_method, Method::access_flags_offset(), Gtmp1);

   {

     Label L;

     __ btst(JVM_ACC_NATIVE, Gtmp1);

     __ br(Assembler::zero, false, Assembler::pt, L);

     __ delayed()->nop();

     __ stop("tried to execute native method as non-native");

     __ bind(L);

   }

   { Label L;

     __ btst(JVM_ACC_ABSTRACT, Gtmp1);

     __ br(Assembler::zero, false, Assembler::pt, L);

     __ delayed()->nop();

     __ stop("tried to execute abstract method as non-abstract");

     __ bind(L);

   }

 #endif // ASSERT

   // generate the code to allocate the interpreter stack frame

   generate_fixed_frame(false);

 #ifdef FAST_DISPATCH

   __ set((intptr_t)Interpreter::dispatch_table(), IdispatchTables);

                                           // set bytecode dispatch table base

 #endif

   //

   // Code to initialize the extra (i.e. non-parm) locals

   //

   Register init_value = noreg;    // will be G0 if we must clear locals

   // The way the code was setup before zerolocals was always true for vanilla java entries.

   // It could only be false for the specialized entries like accessor or empty which have

   // no extra locals so the testing was a waste of time and the extra locals were always

   // initialized. We removed this extra complication to already over complicated code.

   init_value = G0;

   Label clear_loop;

   const Register RconstMethod = O1;

   const Address size_of_parameters(RconstMethod, ConstMethod::size_of_parameters_offset());

   const Address size_of_locals    (RconstMethod, ConstMethod::size_of_locals_offset());

   // NOTE: If you change the frame layout, this code will need to

   // be updated!

   __ ld_ptr( constMethod, RconstMethod );

   __ lduh( size_of_locals, O2 );

   __ lduh( size_of_parameters, O1 );

   __ sll( O2, Interpreter::logStackElementSize, O2);

   __ sll( O1, Interpreter::logStackElementSize, O1 );

   __ sub( Llocals, O2, O2 );

   __ sub( Llocals, O1, O1 );

   __ bind( clear_loop );

   __ inc( O2, wordSize );

   __ cmp( O2, O1 );

   __ brx( Assembler::lessEqualUnsigned, true, Assembler::pt, clear_loop );

   __ delayed()->st_ptr( init_value, O2, 0 );

   const Address do_not_unlock_if_synchronized(G2_thread,

     JavaThread::do_not_unlock_if_synchronized_offset());

   // Since at this point in the method invocation the exception handler

   // would try to exit the monitor of synchronized methods which hasn't

   // been entered yet, we set the thread local variable

   // _do_not_unlock_if_synchronized to true. If any exception was thrown by

   // runtime, exception handling i.e. unlock_if_synchronized_method will

   // check this thread local flag.

   __ movbool(true, G3_scratch);

   __ stbool(G3_scratch, do_not_unlock_if_synchronized);

   // increment invocation counter and check for overflow

   //

   // Note: checking for negative value instead of overflow

   //       so we have a 'sticky' overflow test (may be of

   //       importance as soon as we have true MT/MP)

   Label invocation_counter_overflow;

   Label profile_method;

   Label profile_method_continue;

   Label Lcontinue;

   if (inc_counter) {

     generate_counter_incr(&invocation_counter_overflow, &profile_method, &profile_method_continue);

     if (ProfileInterpreter) {

       __ bind(profile_method_continue);

     }

   }

   __ bind(Lcontinue);

   bang_stack_shadow_pages(false);

   // reset the _do_not_unlock_if_synchronized flag

   __ stbool(G0, do_not_unlock_if_synchronized);

   // check for synchronized methods

   // Must happen AFTER invocation_counter check and stack overflow check,

   // so method is not locked if overflows.

   if (synchronized) {

     lock_method();

   } else {

 #ifdef ASSERT

     { Label ok;

       __ ld(access_flags, O0);

       __ btst(JVM_ACC_SYNCHRONIZED, O0);

       __ br( Assembler::zero, false, Assembler::pt, ok);

       __ delayed()->nop();

       __ stop("method needs synchronization");

       __ bind(ok);

     }

 #endif // ASSERT

   }

   // start execution

   __ verify_thread();

   // jvmti support

   __ notify_method_entry();

   // start executing instructions

   __ dispatch_next(vtos);

   if (inc_counter) {

     if (ProfileInterpreter) {

       // We have decided to profile this method in the interpreter

       __ bind(profile_method);

       __ call_VM(noreg, CAST_FROM_FN_PTR(address, InterpreterRuntime::profile_method));

       __ set_method_data_pointer_for_bcp();

       __ ba_short(profile_method_continue);

     }

     // handle invocation counter overflow

     __ bind(invocation_counter_overflow);

     generate_counter_overflow(Lcontinue);

   }

   return entry;

 }

 //----------------------------------------------------------------------------------------------------

 // Entry points & stack frame layout

 //

 // Here we generate the various kind of entries into the interpreter.

 // The two main entry type are generic bytecode methods and native call method.

 // These both come in synchronized and non-synchronized versions but the

 // frame layout they create is very similar. The other method entry

 // types are really just special purpose entries that are really entry

 // and interpretation all in one. These are for trivial methods like

 // accessor, empty, or special math methods.

 //

 // When control flow reaches any of the entry types for the interpreter

 // the following holds ->

 //

 // C2 Calling Conventions:

 //

 // The entry code below assumes that the following registers are set

 // when coming in:

 //    G5_method: holds the Method* of the method to call

 //    Lesp:    points to the TOS of the callers expression stack

 //             after having pushed all the parameters

 //

 // The entry code does the following to setup an interpreter frame

 //   pop parameters from the callers stack by adjusting Lesp

 //   set O0 to Lesp

 //   compute X = (max_locals - num_parameters)

 //   bump SP up by X to accomadate the extra locals

 //   compute X = max_expression_stack

 //               + vm_local_words

 //               + 16 words of register save area

 //   save frame doing a save sp, -X, sp growing towards lower addresses

 //   set Lbcp, Lmethod, LcpoolCache

 //   set Llocals to i0

 //   set Lmonitors to FP - rounded_vm_local_words

 //   set Lesp to Lmonitors - 4

 //

 //  The frame has now been setup to do the rest of the entry code

 // Try this optimization:  Most method entries could live in a

 // "one size fits all" stack frame without all the dynamic size

 // calculations.  It might be profitable to do all this calculation

 // statically and approximately for "small enough" methods.

 //-----------------------------------------------------------------------------------------------

 // C1 Calling conventions

 //

 // Upon method entry, the following registers are setup:

 //

 // g2 G2_thread: current thread

 // g5 G5_method: method to activate

 // g4 Gargs  : pointer to last argument

 //

 //

 // Stack:

 //

 // +---------------+ <--- sp

 // |               |

 // : reg save area :

 // |               |

 // +---------------+ <--- sp + 0x40

 // |               |

 // : extra 7 slots :      note: these slots are not really needed for the interpreter (fix later)

 // |               |

 // +---------------+ <--- sp + 0x5c

 // |               |

 // :     free      :

 // |               |

 // +---------------+ <--- Gargs

 // |               |

 // :   arguments   :

 // |               |

 // +---------------+

 // |               |

 //

 //

 //

 // AFTER FRAME HAS BEEN SETUP for method interpretation the stack looks like:

 //

 // +---------------+ <--- sp

 // |               |

 // : reg save area :

 // |               |

 // +---------------+ <--- sp + 0x40

 // |               |

 // : extra 7 slots :      note: these slots are not really needed for the interpreter (fix later)

 // |               |

 // +---------------+ <--- sp + 0x5c

 // |               |

 // :               :

 // |               | <--- Lesp

 // +---------------+ <--- Lmonitors (fp - 0x18)

 // |   VM locals   |

 // +---------------+ <--- fp

 // |               |

 // : reg save area :

 // |               |

 // +---------------+ <--- fp + 0x40

 // |               |

 // : extra 7 slots :      note: these slots are not really needed for the interpreter (fix later)

 // |               |

 // +---------------+ <--- fp + 0x5c

 // |               |

 // :     free      :

 // |               |

 // +---------------+

 // |               |

 // : nonarg locals :

 // |               |

 // +---------------+

 // |               |

 // :   arguments   :

 // |               | <--- Llocals

 // +---------------+ <--- Gargs

 // |               |

 static int size_activation_helper(int callee_extra_locals, int max_stack, int monitor_size) {

   // Figure out the size of an interpreter frame (in words) given that we have a fully allocated

   // expression stack, the callee will have callee_extra_locals (so we can account for

   // frame extension) and monitor_size for monitors. Basically we need to calculate

   // this exactly like generate_fixed_frame/generate_compute_interpreter_state.

   //

   //

   // The big complicating thing here is that we must ensure that the stack stays properly

   // aligned. This would be even uglier if monitor size wasn't modulo what the stack

   // needs to be aligned for). We are given that the sp (fp) is already aligned by

   // the caller so we must ensure that it is properly aligned for our callee.

   //

   const int rounded_vm_local_words =

        round_to(frame::interpreter_frame_vm_local_words,WordsPerLong);

   // callee_locals and max_stack are counts, not the size in frame.

   const int locals_size =

        round_to(callee_extra_locals * Interpreter::stackElementWords, WordsPerLong);

   const int max_stack_words = max_stack * Interpreter::stackElementWords;

   return (round_to((max_stack_words

                    + rounded_vm_local_words

                    + frame::memory_parameter_word_sp_offset), WordsPerLong)

                    // already rounded

                    + locals_size + monitor_size);

 }

 // How much stack a method top interpreter activation needs in words.

 int AbstractInterpreter::size_top_interpreter_activation(Method* method) {

   // See call_stub code

   int call_stub_size  = round_to(7 + frame::memory_parameter_word_sp_offset,

                                  WordsPerLong);    // 7 + register save area

   // Save space for one monitor to get into the interpreted method in case

   // the method is synchronized

   int monitor_size    = method->is_synchronized() ?

                                 1*frame::interpreter_frame_monitor_size() : 0;

   return size_activation_helper(method->max_locals(), method->max_stack(),

                                  monitor_size) + call_stub_size;

 }

 int AbstractInterpreter::layout_activation(Method* method,

                                            int tempcount,

                                            int popframe_extra_args,

                                            int moncount,

                                            int caller_actual_parameters,

                                            int callee_param_count,

                                            int callee_local_count,

                                            frame* caller,

                                            frame* interpreter_frame,

                                            bool is_top_frame,

                                            bool is_bottom_frame) {

   // Note: This calculation must exactly parallel the frame setup

   // in InterpreterGenerator::generate_fixed_frame.

   // If f!=NULL, set up the following variables:

   //   - Lmethod

   //   - Llocals

   //   - Lmonitors (to the indicated number of monitors)

   //   - Lesp (to the indicated number of temps)

   // The frame f (if not NULL) on entry is a description of the caller of the frame

   // we are about to layout. We are guaranteed that we will be able to fill in a

   // new interpreter frame as its callee (i.e. the stack space is allocated and

   // the amount was determined by an earlier call to this method with f == NULL).

   // On return f (if not NULL) while describe the interpreter frame we just layed out.

   int monitor_size           = moncount * frame::interpreter_frame_monitor_size();

   int rounded_vm_local_words = round_to(frame::interpreter_frame_vm_local_words,WordsPerLong);

   assert(monitor_size == round_to(monitor_size, WordsPerLong), "must align");

   //

   // Note: if you look closely this appears to be doing something much different

   // than generate_fixed_frame. What is happening is this. On sparc we have to do

   // this dance with interpreter_sp_adjustment because the window save area would

   // appear just below the bottom (tos) of the caller's java expression stack. Because

   // the interpreter want to have the locals completely contiguous generate_fixed_frame

   // will adjust the caller's sp for the "extra locals" (max_locals - parameter_size).

   // Now in generate_fixed_frame the extension of the caller's sp happens in the callee.

   // In this code the opposite occurs the caller adjusts it's own stack base on the callee.

   // This is mostly ok but it does cause a problem when we get to the initial frame (the oldest)

   // because the oldest frame would have adjust its callers frame and yet that frame

   // already exists and isn't part of this array of frames we are unpacking. So at first

   // glance this would seem to mess up that frame. However Deoptimization::fetch_unroll_info_helper()

   // will after it calculates all of the frame's on_stack_size()'s will then figure out the

   // amount to adjust the caller of the initial (oldest) frame and the calculation will all

   // add up. It does seem like it simpler to account for the adjustment here (and remove the

   // callee... parameters here). However this would mean that this routine would have to take

   // the caller frame as input so we could adjust its sp (and set it's interpreter_sp_adjustment)

   // and run the calling loop in the reverse order. This would also would appear to mean making

   // this code aware of what the interactions are when that initial caller fram was an osr or

   // other adapter frame. deoptimization is complicated enough and  hard enough to debug that

   // there is no sense in messing working code.

   //

   int rounded_cls = round_to((callee_local_count - callee_param_count), WordsPerLong);

   assert(rounded_cls == round_to(rounded_cls, WordsPerLong), "must align");

   int raw_frame_size = size_activation_helper(rounded_cls, method->max_stack(),

                                               monitor_size);

   if (interpreter_frame != NULL) {

     // The skeleton frame must already look like an interpreter frame

     // even if not fully filled out.

     assert(interpreter_frame->is_interpreted_frame(), "Must be interpreted frame");

     intptr_t* fp = interpreter_frame->fp();

     JavaThread* thread = JavaThread::current();

     RegisterMap map(thread, false);

     // More verification that skeleton frame is properly walkable

     assert(fp == caller->sp(), "fp must match");

     intptr_t* montop     = fp - rounded_vm_local_words;

     // preallocate monitors (cf. __ add_monitor_to_stack)

     intptr_t* monitors = montop - monitor_size;

     // preallocate stack space

     intptr_t*  esp = monitors - 1 -

                      (tempcount * Interpreter::stackElementWords) -

                      popframe_extra_args;

     int local_words = method->max_locals() * Interpreter::stackElementWords;

     NEEDS_CLEANUP;

     intptr_t* locals;

     if (caller->is_interpreted_frame()) {

       // Can force the locals area to end up properly overlapping the top of the expression stack.

       intptr_t* Lesp_ptr = caller->interpreter_frame_tos_address() - 1;

       // Note that this computation means we replace size_of_parameters() values from the caller

       // interpreter frame's expression stack with our argument locals

       int parm_words  = caller_actual_parameters * Interpreter::stackElementWords;

       locals = Lesp_ptr + parm_words;

       int delta = local_words - parm_words;

       int computed_sp_adjustment = (delta > 0) ? round_to(delta, WordsPerLong) : 0;

       *interpreter_frame->register_addr(I5_savedSP)    = (intptr_t) (fp + computed_sp_adjustment) - STACK_BIAS;

       if (!is_bottom_frame) {

         // Llast_SP is set below for the current frame to SP (with the

         // extra space for the callee's locals). Here we adjust

         // Llast_SP for the caller's frame, removing the extra space

         // for the current method's locals.

         *caller->register_addr(Llast_SP) = *interpreter_frame->register_addr(I5_savedSP);

       } else {

         assert(*caller->register_addr(Llast_SP) >= *interpreter_frame->register_addr(I5_savedSP), "strange Llast_SP");

       }

     } else {

       assert(caller->is_compiled_frame() || caller->is_entry_frame(), "only possible cases");

       // Don't have Lesp available; lay out locals block in the caller

       // adjacent to the register window save area.

       //

       // Compiled frames do not allocate a varargs area which is why this if

       // statement is needed.

       //

       if (caller->is_compiled_frame()) {

         locals = fp + frame::register_save_words + local_words - 1;

       } else {

         locals = fp + frame::memory_parameter_word_sp_offset + local_words - 1;

       }

       if (!caller->is_entry_frame()) {

         // Caller wants his own SP back

         int caller_frame_size = caller->cb()->frame_size();

         *interpreter_frame->register_addr(I5_savedSP) = (intptr_t)(caller->fp() - caller_frame_size) - STACK_BIAS;

       }

     }

     if (TraceDeoptimization) {

       if (caller->is_entry_frame()) {

         // make sure I5_savedSP and the entry frames notion of saved SP

         // agree.  This assertion duplicate a check in entry frame code

         // but catches the failure earlier.

         assert(*caller->register_addr(Lscratch) == *interpreter_frame->register_addr(I5_savedSP),

                "would change callers SP");

       }

       if (caller->is_entry_frame()) {

         tty->print("entry ");

       }

       if (caller->is_compiled_frame()) {

         tty->print("compiled ");

         if (caller->is_deoptimized_frame()) {

           tty->print("(deopt) ");

         }

       }

       if (caller->is_interpreted_frame()) {

         tty->print("interpreted ");

       }

       tty->print_cr("caller fp=0x%x sp=0x%x", caller->fp(), caller->sp());

       tty->print_cr("save area = 0x%x, 0x%x", caller->sp(), caller->sp() + 16);

       tty->print_cr("save area = 0x%x, 0x%x", caller->fp(), caller->fp() + 16);

       tty->print_cr("interpreter fp=0x%x sp=0x%x", interpreter_frame->fp(), interpreter_frame->sp());

       tty->print_cr("save area = 0x%x, 0x%x", interpreter_frame->sp(), interpreter_frame->sp() + 16);

       tty->print_cr("save area = 0x%x, 0x%x", interpreter_frame->fp(), interpreter_frame->fp() + 16);

       tty->print_cr("Llocals = 0x%x", locals);

       tty->print_cr("Lesp = 0x%x", esp);

       tty->print_cr("Lmonitors = 0x%x", monitors);

     }

     if (method->max_locals() > 0) {

       assert(locals < caller->sp() || locals >= (caller->sp() + 16), "locals in save area");

       assert(locals < caller->fp() || locals > (caller->fp() + 16), "locals in save area");

       assert(locals < interpreter_frame->sp() || locals > (interpreter_frame->sp() + 16), "locals in save area");

       assert(locals < interpreter_frame->fp() || locals >= (interpreter_frame->fp() + 16), "locals in save area");

     }

 #ifdef _LP64

     assert(*interpreter_frame->register_addr(I5_savedSP) & 1, "must be odd");

 #endif

     *interpreter_frame->register_addr(Lmethod)     = (intptr_t) method;

     *interpreter_frame->register_addr(Llocals)     = (intptr_t) locals;

     *interpreter_frame->register_addr(Lmonitors)   = (intptr_t) monitors;

     *interpreter_frame->register_addr(Lesp)        = (intptr_t) esp;

     // Llast_SP will be same as SP as there is no adapter space

     *interpreter_frame->register_addr(Llast_SP)    = (intptr_t) interpreter_frame->sp() - STACK_BIAS;

     *interpreter_frame->register_addr(LcpoolCache) = (intptr_t) method->constants()->cache();

 #ifdef FAST_DISPATCH

     *interpreter_frame->register_addr(IdispatchTables) = (intptr_t) Interpreter::dispatch_table();

 #endif

 #ifdef ASSERT

     BasicObjectLock* mp = (BasicObjectLock*)monitors;

     assert(interpreter_frame->interpreter_frame_method() == method, "method matches");

     assert(interpreter_frame->interpreter_frame_local_at(9) == (intptr_t *)((intptr_t)locals - (9 * Interpreter::stackElementSize)), "locals match");

     assert(interpreter_frame->interpreter_frame_monitor_end()   == mp, "monitor_end matches");

     assert(((intptr_t *)interpreter_frame->interpreter_frame_monitor_begin()) == ((intptr_t *)mp)+monitor_size, "monitor_begin matches");

     assert(interpreter_frame->interpreter_frame_tos_address()-1 == esp, "esp matches");

     // check bounds

     intptr_t* lo = interpreter_frame->sp() + (frame::memory_parameter_word_sp_offset - 1);

     intptr_t* hi = interpreter_frame->fp() - rounded_vm_local_words;

     assert(lo < monitors && montop <= hi, "monitors in bounds");

     assert(lo <= esp && esp < monitors, "esp in bounds");

 #endif // ASSERT

   }

   return raw_frame_size;

 }

 //----------------------------------------------------------------------------------------------------

 // Exceptions

 void TemplateInterpreterGenerator::generate_throw_exception() {

   // Entry point in previous activation (i.e., if the caller was interpreted)

   Interpreter::_rethrow_exception_entry = __ pc();

   // O0: exception

   // entry point for exceptions thrown within interpreter code

   Interpreter::_throw_exception_entry = __ pc();

   __ verify_thread();

   // expression stack is undefined here

   // O0: exception, i.e. Oexception

   // Lbcp: exception bcx

   __ verify_oop(Oexception);

   // expression stack must be empty before entering the VM in case of an exception

   __ empty_expression_stack();

   // find exception handler address and preserve exception oop

   // call C routine to find handler and jump to it

   __ call_VM(O1, CAST_FROM_FN_PTR(address, InterpreterRuntime::exception_handler_for_exception), Oexception);

   __ push_ptr(O1); // push exception for exception handler bytecodes

   __ JMP(O0, 0); // jump to exception handler (may be remove activation entry!)

   __ delayed()->nop();

   // if the exception is not handled in the current frame

   // the frame is removed and the exception is rethrown

   // (i.e. exception continuation is _rethrow_exception)

   //

   // Note: At this point the bci is still the bxi for the instruction which caused

   //       the exception and the expression stack is empty. Thus, for any VM calls

   //       at this point, GC will find a legal oop map (with empty expression stack).

   // in current activation

   // tos: exception

   // Lbcp: exception bcp

   //

   // JVMTI PopFrame support

   //

   Interpreter::_remove_activation_preserving_args_entry = __ pc();

   Address popframe_condition_addr(G2_thread, JavaThread::popframe_condition_offset());

   // Set the popframe_processing bit in popframe_condition indicating that we are

   // currently handling popframe, so that call_VMs that may happen later do not trigger new

   // popframe handling cycles.

   __ ld(popframe_condition_addr, G3_scratch);

   __ or3(G3_scratch, JavaThread::popframe_processing_bit, G3_scratch);

   __ stw(G3_scratch, popframe_condition_addr);

   // Empty the expression stack, as in normal exception handling

   __ empty_expression_stack();

   __ unlock_if_synchronized_method(vtos, /* throw_monitor_exception */ false, /* install_monitor_exception */ false);

   {

     // Check to see whether we are returning to a deoptimized frame.

     // (The PopFrame call ensures that the caller of the popped frame is

     // either interpreted or compiled and deoptimizes it if compiled.)

     // In this case, we can't call dispatch_next() after the frame is

     // popped, but instead must save the incoming arguments and restore

     // them after deoptimization has occurred.

     //

     // Note that we don't compare the return PC against the

     // deoptimization blob's unpack entry because of the presence of

     // adapter frames in C2.

     Label caller_not_deoptimized;

     __ call_VM_leaf(L7_thread_cache, CAST_FROM_FN_PTR(address, InterpreterRuntime::interpreter_contains), I7);

     __ br_notnull_short(O0, Assembler::pt, caller_not_deoptimized);

     const Register Gtmp1 = G3_scratch;

     const Register Gtmp2 = G1_scratch;

     const Register RconstMethod = Gtmp1;

     const Address constMethod(Lmethod, Method::const_offset());

     const Address size_of_parameters(RconstMethod, ConstMethod::size_of_parameters_offset());

     // Compute size of arguments for saving when returning to deoptimized caller

     __ ld_ptr(constMethod, RconstMethod);

     __ lduh(size_of_parameters, Gtmp1);

     __ sll(Gtmp1, Interpreter::logStackElementSize, Gtmp1);

     __ sub(Llocals, Gtmp1, Gtmp2);

     __ add(Gtmp2, wordSize, Gtmp2);

     // Save these arguments

     __ call_VM_leaf(L7_thread_cache, CAST_FROM_FN_PTR(address, Deoptimization::popframe_preserve_args), G2_thread, Gtmp1, Gtmp2);

     // Inform deoptimization that it is responsible for restoring these arguments

     __ set(JavaThread::popframe_force_deopt_reexecution_bit, Gtmp1);

     Address popframe_condition_addr(G2_thread, JavaThread::popframe_condition_offset());

     __ st(Gtmp1, popframe_condition_addr);

     // Return from the current method

     // The caller's SP was adjusted upon method entry to accomodate

     // the callee's non-argument locals. Undo that adjustment.

     __ ret();

     __ delayed()->restore(I5_savedSP, G0, SP);

     __ bind(caller_not_deoptimized);

   }

   // Clear the popframe condition flag

   __ stw(G0 /* popframe_inactive */, popframe_condition_addr);

   // Get out of the current method (how this is done depends on the particular compiler calling

   // convention that the interpreter currently follows)

   // The caller's SP was adjusted upon method entry to accomodate

   // the callee's non-argument locals. Undo that adjustment.

   __ restore(I5_savedSP, G0, SP);

   // The method data pointer was incremented already during

   // call profiling. We have to restore the mdp for the current bcp.

   if (ProfileInterpreter) {

     __ set_method_data_pointer_for_bcp();

   }

 #if INCLUDE_JVMTI

   if (EnableInvokeDynamic) {

     Label L_done;

     __ ldub(Address(Lbcp, 0), G1_scratch);  // Load current bytecode

     __ cmp_and_br_short(G1_scratch, Bytecodes::_invokestatic, Assembler::notEqual, Assembler::pn, L_done);

     // The member name argument must be restored if _invokestatic is re-executed after a PopFrame call.

     // Detect such a case in the InterpreterRuntime function and return the member name argument, or NULL.

     __ call_VM(G1_scratch, CAST_FROM_FN_PTR(address, InterpreterRuntime::member_name_arg_or_null), I0, Lmethod, Lbcp);

     __ br_null(G1_scratch, false, Assembler::pn, L_done);

     __ delayed()->nop();

     __ st_ptr(G1_scratch, Lesp, wordSize);

     __ bind(L_done);

   }

 #endif // INCLUDE_JVMTI

   // Resume bytecode interpretation at the current bcp

   __ dispatch_next(vtos);

   // end of JVMTI PopFrame support

   Interpreter::_remove_activation_entry = __ pc();

   // preserve exception over this code sequence (remove activation calls the vm, but oopmaps are not correct here)

   __ pop_ptr(Oexception);                                  // get exception

   // Intel has the following comment:

   //// remove the activation (without doing throws on illegalMonitorExceptions)

   // They remove the activation without checking for bad monitor state.

   // %%% We should make sure this is the right semantics before implementing.

   __ set_vm_result(Oexception);

   __ unlock_if_synchronized_method(vtos, /* throw_monitor_exception */ false);

   __ notify_method_exit(false, vtos, InterpreterMacroAssembler::SkipNotifyJVMTI);

   __ get_vm_result(Oexception);

   __ verify_oop(Oexception);

     const int return_reg_adjustment = frame::pc_return_offset;

   Address issuing_pc_addr(I7, return_reg_adjustment);

   // We are done with this activation frame; find out where to go next.

   // The continuation point will be an exception handler, which expects

   // the following registers set up:

   //

   // Oexception: exception

   // Oissuing_pc: the local call that threw exception

   // Other On: garbage

   // In/Ln:  the contents of the caller's register window

   //

   // We do the required restore at the last possible moment, because we

   // need to preserve some state across a runtime call.

   // (Remember that the caller activation is unknown--it might not be

   // interpreted, so things like Lscratch are useless in the caller.)

   // Although the Intel version uses call_C, we can use the more

   // compact call_VM.  (The only real difference on SPARC is a

   // harmlessly ignored [re]set_last_Java_frame, compared with

   // the Intel code which lacks this.)

   __ mov(Oexception,      Oexception ->after_save());  // get exception in I0 so it will be on O0 after restore

   __ add(issuing_pc_addr, Oissuing_pc->after_save());  // likewise set I1 to a value local to the caller

   __ super_call_VM_leaf(L7_thread_cache,

                         CAST_FROM_FN_PTR(address, SharedRuntime::exception_handler_for_return_address),

                         G2_thread, Oissuing_pc->after_save());

   // The caller's SP was adjusted upon method entry to accomodate

   // the callee's non-argument locals. Undo that adjustment.

   __ JMP(O0, 0);                         // return exception handler in caller

   __ delayed()->restore(I5_savedSP, G0, SP);

   // (same old exception object is already in Oexception; see above)

   // Note that an "issuing PC" is actually the next PC after the call

 }

 //

 // JVMTI ForceEarlyReturn support

 //

 address TemplateInterpreterGenerator::generate_earlyret_entry_for(TosState state) {

   address entry = __ pc();

   __ empty_expression_stack();

   __ load_earlyret_value(state);

   __ ld_ptr(G2_thread, JavaThread::jvmti_thread_state_offset(), G3_scratch);

   Address cond_addr(G3_scratch, JvmtiThreadState::earlyret_state_offset());

   // Clear the earlyret state

   __ stw(G0 /* JvmtiThreadState::earlyret_inactive */, cond_addr);

   __ remove_activation(state,

                        /* throw_monitor_exception */ false,

                        /* install_monitor_exception */ false);

   // The caller's SP was adjusted upon method entry to accomodate

   // the callee's non-argument locals. Undo that adjustment.

   __ ret();                             // return to caller

   __ delayed()->restore(I5_savedSP, G0, SP);

   return entry;

 } // end of JVMTI ForceEarlyReturn support

 //------------------------------------------------------------------------------------------------------------------------

 // Helper for vtos entry point generation

 void TemplateInterpreterGenerator::set_vtos_entry_points(Template* t, address& bep, address& cep, address& sep, address& aep, address& iep, address& lep, address& fep, address& dep, address& vep) {

   assert(t->is_valid() && t->tos_in() == vtos, "illegal template");

   Label L;

   aep = __ pc(); __ push_ptr(); __ ba_short(L);

   fep = __ pc(); __ push_f();   __ ba_short(L);

   dep = __ pc(); __ push_d();   __ ba_short(L);

   lep = __ pc(); __ push_l();   __ ba_short(L);

   iep = __ pc(); __ push_i();

   bep = cep = sep = iep;                        // there aren't any

   vep = __ pc(); __ bind(L);                    // fall through

   generate_and_dispatch(t);

 }

 // --------------------------------------------------------------------------------

 InterpreterGenerator::InterpreterGenerator(StubQueue* code)

  : TemplateInterpreterGenerator(code) {

    generate_all(); // down here so it can be "virtual"

 }

 // --------------------------------------------------------------------------------

 // Non-product code

 #ifndef PRODUCT

 address TemplateInterpreterGenerator::generate_trace_code(TosState state) {

   address entry = __ pc();

   __ push(state);

   __ mov(O7, Lscratch); // protect return address within interpreter

   // Pass a 0 (not used in sparc) and the top of stack to the bytecode tracer

   __ mov( Otos_l2, G3_scratch );

   __ call_VM(noreg, CAST_FROM_FN_PTR(address, SharedRuntime::trace_bytecode), G0, Otos_l1, G3_scratch);

   __ mov(Lscratch, O7); // restore return address

   __ pop(state);

   __ retl();

   __ delayed()->nop();

   return entry;

 }

 // helpers for generate_and_dispatch

 void TemplateInterpreterGenerator::count_bytecode() {

   __ inc_counter(&BytecodeCounter::_counter_value, G3_scratch, G4_scratch);

 }

 void TemplateInterpreterGenerator::histogram_bytecode(Template* t) {

   __ inc_counter(&BytecodeHistogram::_counters[t->bytecode()], G3_scratch, G4_scratch);

 }

 void TemplateInterpreterGenerator::histogram_bytecode_pair(Template* t) {

   AddressLiteral index   (&BytecodePairHistogram::_index);

   AddressLiteral counters((address) &BytecodePairHistogram::_counters);

   // get index, shift out old bytecode, bring in new bytecode, and store it

   // _index = (_index >> log2_number_of_codes) |

   //          (bytecode << log2_number_of_codes);

   __ load_contents(index, G4_scratch);

   __ srl( G4_scratch, BytecodePairHistogram::log2_number_of_codes, G4_scratch );

   __ set( ((int)t->bytecode()) << BytecodePairHistogram::log2_number_of_codes,  G3_scratch );

   __ or3( G3_scratch,  G4_scratch, G4_scratch );

   __ store_contents(G4_scratch, index, G3_scratch);

   // bump bucket contents

   // _counters[_index] ++;

   __ set(counters, G3_scratch);                       // loads into G3_scratch

   __ sll( G4_scratch, LogBytesPerWord, G4_scratch );  // Index is word address

   __ add (G3_scratch, G4_scratch, G3_scratch);        // Add in index

   __ ld (G3_scratch, 0, G4_scratch);

   __ inc (G4_scratch);

   __ st (G4_scratch, 0, G3_scratch);

 }

 void TemplateInterpreterGenerator::trace_bytecode(Template* t) {

   // Call a little run-time stub to avoid blow-up for each bytecode.

   // The run-time runtime saves the right registers, depending on

   // the tosca in-state for the given template.

   address entry = Interpreter::trace_code(t->tos_in());

   guarantee(entry != NULL, "entry must have been generated");

   __ call(entry, relocInfo::none);

   __ delayed()->nop();

 }

 void TemplateInterpreterGenerator::stop_interpreter_at() {

   AddressLiteral counter(&BytecodeCounter::_counter_value);

   __ load_contents(counter, G3_scratch);

   AddressLiteral stop_at(&StopInterpreterAt);

   __ load_ptr_contents(stop_at, G4_scratch);

   __ cmp(G3_scratch, G4_scratch);

   __ breakpoint_trap(Assembler::equal, Assembler::icc);

 }

 #endif // not PRODUCT

 #endif // !CC_INTERP