jdk8-mips64-public/hotspot: src/cpu/sparc/vm/stubGenerator

src/cpu/sparc/vm/stubGenerator_sparc.cpp@2338d41fbd81 (annotated)

src/cpu/sparc/vm/stubGenerator_sparc.cpp

Fri, 30 Apr 2010 08:37:24 -0700

author: twisti
date: Fri, 30 Apr 2010 08:37:24 -0700
changeset 1861: 2338d41fbd81
parent 1858: c640000b7cc1
child 1907: c18cbe5936b8
child 1919: 61b2245abf36
permissions: -rw-r--r--

6943304: remove tagged stack interpreter
Reviewed-by: coleenp, never, gbenson

 /*
  * Copyright 1997-2010 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  */
 #include "incls/_precompiled.incl"
 #include "incls/_stubGenerator_sparc.cpp.incl"
 // Declaration and definition of StubGenerator (no .hpp file).
 // For a more detailed description of the stub routine structure
 // see the comment in stubRoutines.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 ":")
 // Note:  The register L7 is used as L7_thread_cache, and may not be used
 //        any other way within this module.
 static const Register& Lstub_temp = L2;
 // -------------------------------------------------------------------------------------------------------------------------
 // Stub Code definitions
 static address handle_unsafe_access() {
   JavaThread* thread = JavaThread::current();
   address pc  = thread->saved_exception_pc();
   address npc = thread->saved_exception_npc();
   // pc is the instruction which we must emulate
   // doing a no-op is fine:  return garbage from the load
   // request an async exception
   thread->set_pending_unsafe_access_error();
   // return address of next instruction to execute
   return npc;
 }
 class StubGenerator: public StubCodeGenerator {
  private:
 #ifdef PRODUCT
 #define inc_counter_np(a,b,c) (0)
 #else
 #define inc_counter_np(counter, t1, t2) \
   BLOCK_COMMENT("inc_counter " #counter); \
   __ inc_counter(&counter, t1, t2);
 #endif
   //----------------------------------------------------------------------------------------------------
   // Call stubs are used to call Java from C
   address generate_call_stub(address& return_pc) {
     StubCodeMark mark(this, "StubRoutines", "call_stub");
     address start = __ pc();
     // Incoming arguments:
     //
     // o0         : call wrapper address
     // o1         : result (address)
     // o2         : result type
     // o3         : method
     // o4         : (interpreter) entry point
     // o5         : parameters (address)
     // [sp + 0x5c]: parameter size (in words)
     // [sp + 0x60]: thread
     //
     // +---------------+ <--- sp + 0
     // |               |
     // . reg save area .
     // |               |
     // +---------------+ <--- sp + 0x40
     // |               |
     // . extra 7 slots .
     // |               |
     // +---------------+ <--- sp + 0x5c
     // |  param. size  |
     // +---------------+ <--- sp + 0x60
     // |    thread     |
     // +---------------+
     // |               |
     // note: if the link argument position changes, adjust
     //       the code in frame::entry_frame_call_wrapper()
     const Argument link           = Argument(0, false); // used only for GC
     const Argument result         = Argument(1, false);
     const Argument result_type    = Argument(2, false);
     const Argument method         = Argument(3, false);
     const Argument entry_point    = Argument(4, false);
     const Argument parameters     = Argument(5, false);
     const Argument parameter_size = Argument(6, false);
     const Argument thread         = Argument(7, false);
     // setup thread register
     __ ld_ptr(thread.as_address(), G2_thread);
     __ reinit_heapbase();
 #ifdef ASSERT
     // make sure we have no pending exceptions
     { const Register t = G3_scratch;
       Label L;
       __ ld_ptr(G2_thread, in_bytes(Thread::pending_exception_offset()), t);
       __ br_null(t, false, Assembler::pt, L);
       __ delayed()->nop();
       __ stop("StubRoutines::call_stub: entered with pending exception");
       __ bind(L);
     }
 #endif
     // create activation frame & allocate space for parameters
     { const Register t = G3_scratch;
       __ ld_ptr(parameter_size.as_address(), t);                // get parameter size (in words)
       __ add(t, frame::memory_parameter_word_sp_offset, t);     // add space for save area (in words)
       __ round_to(t, WordsPerLong);                             // make sure it is multiple of 2 (in words)
       __ sll(t, Interpreter::logStackElementSize, t);           // compute number of bytes
       __ neg(t);                                                // negate so it can be used with save
       __ save(SP, t, SP);                                       // setup new frame
     }
     // +---------------+ <--- sp + 0
     // |               |
     // . reg save area .
     // |               |
     // +---------------+ <--- sp + 0x40
     // |               |
     // . extra 7 slots .
     // |               |
     // +---------------+ <--- sp + 0x5c
     // |  empty slot   |      (only if parameter size is even)
     // +---------------+
     // |               |
     // .  parameters   .
     // |               |
     // +---------------+ <--- fp + 0
     // |               |
     // . reg save area .
     // |               |
     // +---------------+ <--- fp + 0x40
     // |               |
     // . extra 7 slots .
     // |               |
     // +---------------+ <--- fp + 0x5c
     // |  param. size  |
     // +---------------+ <--- fp + 0x60
     // |    thread     |
     // +---------------+
     // |               |
     // pass parameters if any
     BLOCK_COMMENT("pass parameters if any");
     { const Register src = parameters.as_in().as_register();
       const Register dst = Lentry_args;
       const Register tmp = G3_scratch;
       const Register cnt = G4_scratch;
       // test if any parameters & setup of Lentry_args
       Label exit;
       __ ld_ptr(parameter_size.as_in().as_address(), cnt);      // parameter counter
       __ add( FP, STACK_BIAS, dst );
       __ tst(cnt);
       __ br(Assembler::zero, false, Assembler::pn, exit);
       __ delayed()->sub(dst, BytesPerWord, dst);                 // setup Lentry_args
       // copy parameters if any
       Label loop;
       __ BIND(loop);
       // Store parameter value
       __ ld_ptr(src, 0, tmp);
       __ add(src, BytesPerWord, src);
       __ st_ptr(tmp, dst, 0);
       __ deccc(cnt);
       __ br(Assembler::greater, false, Assembler::pt, loop);
       __ delayed()->sub(dst, Interpreter::stackElementSize, dst);
       // done
       __ BIND(exit);
     }
     // setup parameters, method & call Java function
 #ifdef ASSERT
     // layout_activation_impl checks it's notion of saved SP against
     // this register, so if this changes update it as well.
     const Register saved_SP = Lscratch;
     __ mov(SP, saved_SP);                               // keep track of SP before call
 #endif
     // setup parameters
     const Register t = G3_scratch;
     __ ld_ptr(parameter_size.as_in().as_address(), t); // get parameter size (in words)
     __ sll(t, Interpreter::logStackElementSize, t);    // compute number of bytes
     __ sub(FP, t, Gargs);                              // setup parameter pointer
 #ifdef _LP64
     __ add( Gargs, STACK_BIAS, Gargs );                // Account for LP64 stack bias
 #endif
     __ mov(SP, O5_savedSP);
     // do the call
     //
     // the following register must be setup:
     //
     // G2_thread
     // G5_method
     // Gargs
     BLOCK_COMMENT("call Java function");
     __ jmpl(entry_point.as_in().as_register(), G0, O7);
     __ delayed()->mov(method.as_in().as_register(), G5_method);   // setup method
     BLOCK_COMMENT("call_stub_return_address:");
     return_pc = __ pc();
     // The callee, if it wasn't interpreted, can return with SP changed so
     // we can no longer assert of change of SP.
     // store result depending on type
     // (everything that is not T_OBJECT, T_LONG, T_FLOAT, or T_DOUBLE
     //  is treated as T_INT)
     { const Register addr = result     .as_in().as_register();
       const Register type = result_type.as_in().as_register();
       Label is_long, is_float, is_double, is_object, exit;
       __            cmp(type, T_OBJECT);  __ br(Assembler::equal, false, Assembler::pn, is_object);
       __ delayed()->cmp(type, T_FLOAT);   __ br(Assembler::equal, false, Assembler::pn, is_float);
       __ delayed()->cmp(type, T_DOUBLE);  __ br(Assembler::equal, false, Assembler::pn, is_double);
       __ delayed()->cmp(type, T_LONG);    __ br(Assembler::equal, false, Assembler::pn, is_long);
       __ delayed()->nop();
       // store int result
       __ st(O0, addr, G0);
       __ BIND(exit);
       __ ret();
       __ delayed()->restore();
       __ BIND(is_object);
       __ ba(false, exit);
       __ delayed()->st_ptr(O0, addr, G0);
       __ BIND(is_float);
       __ ba(false, exit);
       __ delayed()->stf(FloatRegisterImpl::S, F0, addr, G0);
       __ BIND(is_double);
       __ ba(false, exit);
       __ delayed()->stf(FloatRegisterImpl::D, F0, addr, G0);
       __ BIND(is_long);
 #ifdef _LP64
       __ ba(false, exit);
       __ delayed()->st_long(O0, addr, G0);      // store entire long
 #else
 #if 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 we simply always use G1.
   // 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.
       __ ba(false, exit);
       __ delayed()->stx(G1, addr, G0);  // store entire long
 #else
       __ st(O1, addr, BytesPerInt);
       __ ba(false, exit);
       __ delayed()->st(O0, addr, G0);
 #endif /* COMPILER2 */
 #endif /* _LP64 */
      }
      return start;
   }
   //----------------------------------------------------------------------------------------------------
   // Return point for a Java call if there's an exception thrown in Java code.
   // The exception is caught and transformed into a pending exception stored in
   // JavaThread that can be tested from within the VM.
   //
   // Oexception: exception oop
   address generate_catch_exception() {
     StubCodeMark mark(this, "StubRoutines", "catch_exception");
     address start = __ pc();
     // verify that thread corresponds
     __ verify_thread();
     const Register& temp_reg = Gtemp;
     Address pending_exception_addr    (G2_thread, Thread::pending_exception_offset());
     Address exception_file_offset_addr(G2_thread, Thread::exception_file_offset   ());
     Address exception_line_offset_addr(G2_thread, Thread::exception_line_offset   ());
     // set pending exception
     __ verify_oop(Oexception);
     __ st_ptr(Oexception, pending_exception_addr);
     __ set((intptr_t)__FILE__, temp_reg);
     __ st_ptr(temp_reg, exception_file_offset_addr);
     __ set((intptr_t)__LINE__, temp_reg);
     __ st(temp_reg, exception_line_offset_addr);
     // complete return to VM
     assert(StubRoutines::_call_stub_return_address != NULL, "must have been generated before");
     AddressLiteral stub_ret(StubRoutines::_call_stub_return_address);
     __ jump_to(stub_ret, temp_reg);
     __ delayed()->nop();
     return start;
   }
   //----------------------------------------------------------------------------------------------------
   // Continuation point for runtime calls returning with a pending exception
   // The pending exception check happened in the runtime or native call stub
   // The pending exception in Thread is converted into a Java-level exception
   //
   // Contract with Java-level exception handler: O0 = exception
   //                                             O1 = throwing pc
   address generate_forward_exception() {
     StubCodeMark mark(this, "StubRoutines", "forward_exception");
     address start = __ pc();
     // Upon entry, O7 has the return address returning into Java
     // (interpreted or compiled) code; i.e. the return address
     // becomes the throwing pc.
     const Register& handler_reg = Gtemp;
     Address exception_addr(G2_thread, Thread::pending_exception_offset());
 #ifdef ASSERT
     // make sure that this code is only executed if there is a pending exception
     { Label L;
       __ ld_ptr(exception_addr, Gtemp);
       __ br_notnull(Gtemp, false, Assembler::pt, L);
       __ delayed()->nop();
       __ stop("StubRoutines::forward exception: no pending exception (1)");
       __ bind(L);
     }
 #endif
     // compute exception handler into handler_reg
     __ get_thread();
     __ ld_ptr(exception_addr, Oexception);
     __ verify_oop(Oexception);
     __ save_frame(0);             // compensates for compiler weakness
     __ add(O7->after_save(), frame::pc_return_offset, Lscratch); // save the issuing PC
     BLOCK_COMMENT("call exception_handler_for_return_address");
     __ call_VM_leaf(L7_thread_cache, CAST_FROM_FN_PTR(address, SharedRuntime::exception_handler_for_return_address), G2_thread, Lscratch);
     __ mov(O0, handler_reg);
     __ restore();                 // compensates for compiler weakness
     __ ld_ptr(exception_addr, Oexception);
     __ add(O7, frame::pc_return_offset, Oissuing_pc); // save the issuing PC
 #ifdef ASSERT
     // make sure exception is set
     { Label L;
       __ br_notnull(Oexception, false, Assembler::pt, L);
       __ delayed()->nop();
       __ stop("StubRoutines::forward exception: no pending exception (2)");
       __ bind(L);
     }
 #endif
     // jump to exception handler
     __ jmp(handler_reg, 0);
     // clear pending exception
     __ delayed()->st_ptr(G0, exception_addr);
     return start;
   }
   //------------------------------------------------------------------------------------------------------------------------
   // Continuation point for throwing of implicit exceptions that are not handled in
   // the current activation. Fabricates an exception oop and initiates normal
   // exception dispatching in this frame. Only callee-saved registers are preserved
   // (through the normal register window / RegisterMap handling).
   // If the compiler needs all registers to be preserved between the fault
   // point and the exception handler then it must assume responsibility for that in
   // AbstractCompiler::continuation_for_implicit_null_exception or
   // continuation_for_implicit_division_by_zero_exception. All other implicit
   // exceptions (e.g., NullPointerException or AbstractMethodError on entry) are
   // either at call sites or otherwise assume that stack unwinding will be initiated,
   // so caller saved registers were assumed volatile in the compiler.
   // Note that we generate only this stub into a RuntimeStub, because it needs to be
   // properly traversed and ignored during GC, so we change the meaning of the "__"
   // macro within this method.
 #undef __
 #define __ masm->
   address generate_throw_exception(const char* name, address runtime_entry, bool restore_saved_exception_pc) {
 #ifdef ASSERT
     int insts_size = VerifyThread ? 1 * K : 600;
 #else
     int insts_size = VerifyThread ? 1 * K : 256;
 #endif /* ASSERT */
     int locs_size  = 32;
     CodeBuffer      code(name, insts_size, locs_size);
     MacroAssembler* masm = new MacroAssembler(&code);
     __ verify_thread();
     // This is an inlined and slightly modified version of call_VM
     // which has the ability to fetch the return PC out of thread-local storage
     __ assert_not_delayed();
     // Note that we always push a frame because on the SPARC
     // architecture, for all of our implicit exception kinds at call
     // sites, the implicit exception is taken before the callee frame
     // is pushed.
     __ save_frame(0);
     int frame_complete = __ offset();
     if (restore_saved_exception_pc) {
       __ ld_ptr(G2_thread, JavaThread::saved_exception_pc_offset(), I7);
       __ sub(I7, frame::pc_return_offset, I7);
     }
     // Note that we always have a runtime stub frame on the top of stack by this point
     Register last_java_sp = SP;
     // 64-bit last_java_sp is biased!
     __ set_last_Java_frame(last_java_sp, G0);
     if (VerifyThread)  __ mov(G2_thread, O0); // about to be smashed; pass early
     __ save_thread(noreg);
     // do the call
     BLOCK_COMMENT("call runtime_entry");
     __ call(runtime_entry, relocInfo::runtime_call_type);
     if (!VerifyThread)
       __ delayed()->mov(G2_thread, O0);  // pass thread as first argument
     else
       __ delayed()->nop();             // (thread already passed)
     __ restore_thread(noreg);
     __ reset_last_Java_frame();
     // check for pending exceptions. use Gtemp as scratch register.
 #ifdef ASSERT
     Label L;
     Address exception_addr(G2_thread, Thread::pending_exception_offset());
     Register scratch_reg = Gtemp;
     __ ld_ptr(exception_addr, scratch_reg);
     __ br_notnull(scratch_reg, false, Assembler::pt, L);
     __ delayed()->nop();
     __ should_not_reach_here();
     __ bind(L);
 #endif // ASSERT
     BLOCK_COMMENT("call forward_exception_entry");
     __ call(StubRoutines::forward_exception_entry(), relocInfo::runtime_call_type);
     // we use O7 linkage so that forward_exception_entry has the issuing PC
     __ delayed()->restore();
     RuntimeStub* stub = RuntimeStub::new_runtime_stub(name, &code, frame_complete, masm->total_frame_size_in_bytes(0), NULL, false);
     return stub->entry_point();
   }
 #undef __
 #define __ _masm->
   // Generate a routine that sets all the registers so we
   // can tell if the stop routine prints them correctly.
   address generate_test_stop() {
     StubCodeMark mark(this, "StubRoutines", "test_stop");
     address start = __ pc();
     int i;
     __ save_frame(0);
     static jfloat zero = 0.0, one = 1.0;
     // put addr in L0, then load through L0 to F0
     __ set((intptr_t)&zero, L0);  __ ldf( FloatRegisterImpl::S, L0, 0, F0);
     __ set((intptr_t)&one,  L0);  __ ldf( FloatRegisterImpl::S, L0, 0, F1); // 1.0 to F1
     // use add to put 2..18 in F2..F18
     for ( i = 2;  i <= 18;  ++i ) {
       __ fadd( FloatRegisterImpl::S, F1, as_FloatRegister(i-1),  as_FloatRegister(i));
     }
     // Now put double 2 in F16, double 18 in F18
     __ ftof( FloatRegisterImpl::S, FloatRegisterImpl::D, F2, F16 );
     __ ftof( FloatRegisterImpl::S, FloatRegisterImpl::D, F18, F18 );
     // use add to put 20..32 in F20..F32
     for (i = 20; i < 32; i += 2) {
       __ fadd( FloatRegisterImpl::D, F16, as_FloatRegister(i-2),  as_FloatRegister(i));
     }
     // put 0..7 in i's, 8..15 in l's, 16..23 in o's, 24..31 in g's
     for ( i = 0; i < 8; ++i ) {
       if (i < 6) {
         __ set(     i, as_iRegister(i));
         __ set(16 + i, as_oRegister(i));
         __ set(24 + i, as_gRegister(i));
       }
       __ set( 8 + i, as_lRegister(i));
     }
     __ stop("testing stop");
     __ ret();
     __ delayed()->restore();
     return start;
   }
   address generate_stop_subroutine() {
     StubCodeMark mark(this, "StubRoutines", "stop_subroutine");
     address start = __ pc();
     __ stop_subroutine();
     return start;
   }
   address generate_flush_callers_register_windows() {
     StubCodeMark mark(this, "StubRoutines", "flush_callers_register_windows");
     address start = __ pc();
     __ flush_windows();
     __ retl(false);
     __ delayed()->add( FP, STACK_BIAS, O0 );
     // The returned value must be a stack pointer whose register save area
     // is flushed, and will stay flushed while the caller executes.
     return start;
   }
   // Helper functions for v8 atomic operations.
   //
   void get_v8_oop_lock_ptr(Register lock_ptr_reg, Register mark_oop_reg, Register scratch_reg) {
     if (mark_oop_reg == noreg) {
       address lock_ptr = (address)StubRoutines::Sparc::atomic_memory_operation_lock_addr();
       __ set((intptr_t)lock_ptr, lock_ptr_reg);
     } else {
       assert(scratch_reg != noreg, "just checking");
       address lock_ptr = (address)StubRoutines::Sparc::_v8_oop_lock_cache;
       __ set((intptr_t)lock_ptr, lock_ptr_reg);
       __ and3(mark_oop_reg, StubRoutines::Sparc::v8_oop_lock_mask_in_place, scratch_reg);
       __ add(lock_ptr_reg, scratch_reg, lock_ptr_reg);
     }
   }
   void generate_v8_lock_prologue(Register lock_reg, Register lock_ptr_reg, Register yield_reg, Label& retry, Label& dontyield, Register mark_oop_reg = noreg, Register scratch_reg = noreg) {
     get_v8_oop_lock_ptr(lock_ptr_reg, mark_oop_reg, scratch_reg);
     __ set(StubRoutines::Sparc::locked, lock_reg);
     // Initialize yield counter
     __ mov(G0,yield_reg);
     __ BIND(retry);
     __ cmp(yield_reg, V8AtomicOperationUnderLockSpinCount);
     __ br(Assembler::less, false, Assembler::pt, dontyield);
     __ delayed()->nop();
     // This code can only be called from inside the VM, this
     // stub is only invoked from Atomic::add().  We do not
     // want to use call_VM, because _last_java_sp and such
     // must already be set.
     //
     // Save the regs and make space for a C call
     __ save(SP, -96, SP);
     __ save_all_globals_into_locals();
     BLOCK_COMMENT("call os::naked_sleep");
     __ call(CAST_FROM_FN_PTR(address, os::naked_sleep));
     __ delayed()->nop();
     __ restore_globals_from_locals();
     __ restore();
     // reset the counter
     __ mov(G0,yield_reg);
     __ BIND(dontyield);
     // try to get lock
     __ swap(lock_ptr_reg, 0, lock_reg);
     // did we get the lock?
     __ cmp(lock_reg, StubRoutines::Sparc::unlocked);
     __ br(Assembler::notEqual, true, Assembler::pn, retry);
     __ delayed()->add(yield_reg,1,yield_reg);
     // yes, got lock. do the operation here.
   }
   void generate_v8_lock_epilogue(Register lock_reg, Register lock_ptr_reg, Register yield_reg, Label& retry, Label& dontyield, Register mark_oop_reg = noreg, Register scratch_reg = noreg) {
     __ st(lock_reg, lock_ptr_reg, 0); // unlock
   }
   // Support for jint Atomic::xchg(jint exchange_value, volatile jint* dest).
   //
   // Arguments :
   //
   //      exchange_value: O0
   //      dest:           O1
   //
   // Results:
   //
   //     O0: the value previously stored in dest
   //
   address generate_atomic_xchg() {
     StubCodeMark mark(this, "StubRoutines", "atomic_xchg");
     address start = __ pc();
     if (UseCASForSwap) {
       // Use CAS instead of swap, just in case the MP hardware
       // prefers to work with just one kind of synch. instruction.
       Label retry;
       __ BIND(retry);
       __ mov(O0, O3);       // scratch copy of exchange value
       __ ld(O1, 0, O2);     // observe the previous value
       // try to replace O2 with O3
       __ cas_under_lock(O1, O2, O3,
       (address)StubRoutines::Sparc::atomic_memory_operation_lock_addr(),false);
       __ cmp(O2, O3);
       __ br(Assembler::notEqual, false, Assembler::pn, retry);
       __ delayed()->nop();
       __ retl(false);
       __ delayed()->mov(O2, O0);  // report previous value to caller
     } else {
       if (VM_Version::v9_instructions_work()) {
         __ retl(false);
         __ delayed()->swap(O1, 0, O0);
       } else {
         const Register& lock_reg = O2;
         const Register& lock_ptr_reg = O3;
         const Register& yield_reg = O4;
         Label retry;
         Label dontyield;
         generate_v8_lock_prologue(lock_reg, lock_ptr_reg, yield_reg, retry, dontyield);
         // got the lock, do the swap
         __ swap(O1, 0, O0);
         generate_v8_lock_epilogue(lock_reg, lock_ptr_reg, yield_reg, retry, dontyield);
         __ retl(false);
         __ delayed()->nop();
       }
     }
     return start;
   }
   // Support for jint Atomic::cmpxchg(jint exchange_value, volatile jint* dest, jint compare_value)
   //
   // Arguments :
   //
   //      exchange_value: O0
   //      dest:           O1
   //      compare_value:  O2
   //
   // Results:
   //
   //     O0: the value previously stored in dest
   //
   // Overwrites (v8): O3,O4,O5
   //
   address generate_atomic_cmpxchg() {
     StubCodeMark mark(this, "StubRoutines", "atomic_cmpxchg");
     address start = __ pc();
     // cmpxchg(dest, compare_value, exchange_value)
     __ cas_under_lock(O1, O2, O0,
       (address)StubRoutines::Sparc::atomic_memory_operation_lock_addr(),false);
     __ retl(false);
     __ delayed()->nop();
     return start;
   }
   // Support for jlong Atomic::cmpxchg(jlong exchange_value, volatile jlong *dest, jlong compare_value)
   //
   // Arguments :
   //
   //      exchange_value: O1:O0
   //      dest:           O2
   //      compare_value:  O4:O3
   //
   // Results:
   //
   //     O1:O0: the value previously stored in dest
   //
   // This only works on V9, on V8 we don't generate any
   // code and just return NULL.
   //
   // Overwrites: G1,G2,G3
   //
   address generate_atomic_cmpxchg_long() {
     StubCodeMark mark(this, "StubRoutines", "atomic_cmpxchg_long");
     address start = __ pc();
     if (!VM_Version::supports_cx8())
         return NULL;;
     __ sllx(O0, 32, O0);
     __ srl(O1, 0, O1);
     __ or3(O0,O1,O0);      // O0 holds 64-bit value from compare_value
     __ sllx(O3, 32, O3);
     __ srl(O4, 0, O4);
     __ or3(O3,O4,O3);     // O3 holds 64-bit value from exchange_value
     __ casx(O2, O3, O0);
     __ srl(O0, 0, O1);    // unpacked return value in O1:O0
     __ retl(false);
     __ delayed()->srlx(O0, 32, O0);
     return start;
   }
   // Support for jint Atomic::add(jint add_value, volatile jint* dest).
   //
   // Arguments :
   //
   //      add_value: O0   (e.g., +1 or -1)
   //      dest:      O1
   //
   // Results:
   //
   //     O0: the new value stored in dest
   //
   // Overwrites (v9): O3
   // Overwrites (v8): O3,O4,O5
   //
   address generate_atomic_add() {
     StubCodeMark mark(this, "StubRoutines", "atomic_add");
     address start = __ pc();
     __ BIND(_atomic_add_stub);
     if (VM_Version::v9_instructions_work()) {
       Label(retry);
       __ BIND(retry);
       __ lduw(O1, 0, O2);
       __ add(O0,   O2, O3);
       __ cas(O1,   O2, O3);
       __ cmp(      O2, O3);
       __ br(Assembler::notEqual, false, Assembler::pn, retry);
       __ delayed()->nop();
       __ retl(false);
       __ delayed()->add(O0, O2, O0); // note that cas made O2==O3
     } else {
       const Register& lock_reg = O2;
       const Register& lock_ptr_reg = O3;
       const Register& value_reg = O4;
       const Register& yield_reg = O5;
       Label(retry);
       Label(dontyield);
       generate_v8_lock_prologue(lock_reg, lock_ptr_reg, yield_reg, retry, dontyield);
       // got lock, do the increment
       __ ld(O1, 0, value_reg);
       __ add(O0, value_reg, value_reg);
       __ st(value_reg, O1, 0);
       // %%% only for RMO and PSO
       __ membar(Assembler::StoreStore);
       generate_v8_lock_epilogue(lock_reg, lock_ptr_reg, yield_reg, retry, dontyield);
       __ retl(false);
       __ delayed()->mov(value_reg, O0);
     }
     return start;
   }
   Label _atomic_add_stub;  // called from other stubs
   //------------------------------------------------------------------------------------------------------------------------
   // The following routine generates a subroutine to throw an asynchronous
   // UnknownError when an unsafe access gets a fault that could not be
   // reasonably prevented by the programmer.  (Example: SIGBUS/OBJERR.)
   //
   // Arguments :
   //
   //      trapping PC:    O7
   //
   // Results:
   //     posts an asynchronous exception, skips the trapping instruction
   //
   address generate_handler_for_unsafe_access() {
     StubCodeMark mark(this, "StubRoutines", "handler_for_unsafe_access");
     address start = __ pc();
     const int preserve_register_words = (64 * 2);
     Address preserve_addr(FP, (-preserve_register_words * wordSize) + STACK_BIAS);
     Register Lthread = L7_thread_cache;
     int i;
     __ save_frame(0);
     __ mov(G1, L1);
     __ mov(G2, L2);
     __ mov(G3, L3);
     __ mov(G4, L4);
     __ mov(G5, L5);
     for (i = 0; i < (VM_Version::v9_instructions_work() ? 64 : 32); i += 2) {
       __ stf(FloatRegisterImpl::D, as_FloatRegister(i), preserve_addr, i * wordSize);
     }
     address entry_point = CAST_FROM_FN_PTR(address, handle_unsafe_access);
     BLOCK_COMMENT("call handle_unsafe_access");
     __ call(entry_point, relocInfo::runtime_call_type);
     __ delayed()->nop();
     __ mov(L1, G1);
     __ mov(L2, G2);
     __ mov(L3, G3);
     __ mov(L4, G4);
     __ mov(L5, G5);
     for (i = 0; i < (VM_Version::v9_instructions_work() ? 64 : 32); i += 2) {
       __ ldf(FloatRegisterImpl::D, preserve_addr, as_FloatRegister(i), i * wordSize);
     }
     __ verify_thread();
     __ jmp(O0, 0);
     __ delayed()->restore();
     return start;
   }
   // Support for uint StubRoutine::Sparc::partial_subtype_check( Klass sub, Klass super );
   // Arguments :
   //
   //      ret  : O0, returned
   //      icc/xcc: set as O0 (depending on wordSize)
   //      sub  : O1, argument, not changed
   //      super: O2, argument, not changed
   //      raddr: O7, blown by call
   address generate_partial_subtype_check() {
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", "partial_subtype_check");
     address start = __ pc();
     Label miss;
 #if defined(COMPILER2) && !defined(_LP64)
     // Do not use a 'save' because it blows the 64-bit O registers.
     __ add(SP,-4*wordSize,SP);  // Make space for 4 temps (stack must be 2 words aligned)
     __ st_ptr(L0,SP,(frame::register_save_words+0)*wordSize);
     __ st_ptr(L1,SP,(frame::register_save_words+1)*wordSize);
     __ st_ptr(L2,SP,(frame::register_save_words+2)*wordSize);
     __ st_ptr(L3,SP,(frame::register_save_words+3)*wordSize);
     Register Rret   = O0;
     Register Rsub   = O1;
     Register Rsuper = O2;
 #else
     __ save_frame(0);
     Register Rret   = I0;
     Register Rsub   = I1;
     Register Rsuper = I2;
 #endif
     Register L0_ary_len = L0;
     Register L1_ary_ptr = L1;
     Register L2_super   = L2;
     Register L3_index   = L3;
     __ check_klass_subtype_slow_path(Rsub, Rsuper,
                                      L0, L1, L2, L3,
                                      NULL, &miss);
     // Match falls through here.
     __ addcc(G0,0,Rret);        // set Z flags, Z result
 #if defined(COMPILER2) && !defined(_LP64)
     __ ld_ptr(SP,(frame::register_save_words+0)*wordSize,L0);
     __ ld_ptr(SP,(frame::register_save_words+1)*wordSize,L1);
     __ ld_ptr(SP,(frame::register_save_words+2)*wordSize,L2);
     __ ld_ptr(SP,(frame::register_save_words+3)*wordSize,L3);
     __ retl();                  // Result in Rret is zero; flags set to Z
     __ delayed()->add(SP,4*wordSize,SP);
 #else
     __ ret();                   // Result in Rret is zero; flags set to Z
     __ delayed()->restore();
 #endif
     __ BIND(miss);
     __ addcc(G0,1,Rret);        // set NZ flags, NZ result
 #if defined(COMPILER2) && !defined(_LP64)
     __ ld_ptr(SP,(frame::register_save_words+0)*wordSize,L0);
     __ ld_ptr(SP,(frame::register_save_words+1)*wordSize,L1);
     __ ld_ptr(SP,(frame::register_save_words+2)*wordSize,L2);
     __ ld_ptr(SP,(frame::register_save_words+3)*wordSize,L3);
     __ retl();                  // Result in Rret is != 0; flags set to NZ
     __ delayed()->add(SP,4*wordSize,SP);
 #else
     __ ret();                   // Result in Rret is != 0; flags set to NZ
     __ delayed()->restore();
 #endif
     return start;
   }
   // Called from MacroAssembler::verify_oop
   //
   address generate_verify_oop_subroutine() {
     StubCodeMark mark(this, "StubRoutines", "verify_oop_stub");
     address start = __ pc();
     __ verify_oop_subroutine();
     return start;
   }
   static address disjoint_byte_copy_entry;
   static address disjoint_short_copy_entry;
   static address disjoint_int_copy_entry;
   static address disjoint_long_copy_entry;
   static address disjoint_oop_copy_entry;
   static address byte_copy_entry;
   static address short_copy_entry;
   static address int_copy_entry;
   static address long_copy_entry;
   static address oop_copy_entry;
   static address checkcast_copy_entry;
   //
   // Verify that a register contains clean 32-bits positive value
   // (high 32-bits are 0) so it could be used in 64-bits shifts (sllx, srax).
   //
   //  Input:
   //    Rint  -  32-bits value
   //    Rtmp  -  scratch
   //
   void assert_clean_int(Register Rint, Register Rtmp) {
 #if defined(ASSERT) && defined(_LP64)
     __ signx(Rint, Rtmp);
     __ cmp(Rint, Rtmp);
     __ breakpoint_trap(Assembler::notEqual, Assembler::xcc);
 #endif
   }
   //
   //  Generate overlap test for array copy stubs
   //
   //  Input:
   //    O0    -  array1
   //    O1    -  array2
   //    O2    -  element count
   //
   //  Kills temps:  O3, O4
   //
   void array_overlap_test(address no_overlap_target, int log2_elem_size) {
     assert(no_overlap_target != NULL, "must be generated");
     array_overlap_test(no_overlap_target, NULL, log2_elem_size);
   }
   void array_overlap_test(Label& L_no_overlap, int log2_elem_size) {
     array_overlap_test(NULL, &L_no_overlap, log2_elem_size);
   }
   void array_overlap_test(address no_overlap_target, Label* NOLp, int log2_elem_size) {
     const Register from       = O0;
     const Register to         = O1;
     const Register count      = O2;
     const Register to_from    = O3; // to - from
     const Register byte_count = O4; // count << log2_elem_size
       __ subcc(to, from, to_from);
       __ sll_ptr(count, log2_elem_size, byte_count);
       if (NOLp == NULL)
         __ brx(Assembler::lessEqualUnsigned, false, Assembler::pt, no_overlap_target);
       else
         __ brx(Assembler::lessEqualUnsigned, false, Assembler::pt, (*NOLp));
       __ delayed()->cmp(to_from, byte_count);
       if (NOLp == NULL)
         __ brx(Assembler::greaterEqual, false, Assembler::pt, no_overlap_target);
       else
         __ brx(Assembler::greaterEqual, false, Assembler::pt, (*NOLp));
       __ delayed()->nop();
   }
   //
   //  Generate pre-write barrier for array.
   //
   //  Input:
   //     addr     - register containing starting address
   //     count    - register containing element count
   //     tmp      - scratch register
   //
   //  The input registers are overwritten.
   //
   void gen_write_ref_array_pre_barrier(Register addr, Register count) {
     BarrierSet* bs = Universe::heap()->barrier_set();
     if (bs->has_write_ref_pre_barrier()) {
       assert(bs->has_write_ref_array_pre_opt(),
              "Else unsupported barrier set.");
       __ save_frame(0);
       // Save the necessary global regs... will be used after.
       if (addr->is_global()) {
         __ mov(addr, L0);
       }
       if (count->is_global()) {
         __ mov(count, L1);
       }
       __ mov(addr->after_save(), O0);
       // Get the count into O1
       __ call(CAST_FROM_FN_PTR(address, BarrierSet::static_write_ref_array_pre));
       __ delayed()->mov(count->after_save(), O1);
       if (addr->is_global()) {
         __ mov(L0, addr);
       }
       if (count->is_global()) {
         __ mov(L1, count);
       }
       __ restore();
     }
   }
   //
   //  Generate post-write barrier for array.
   //
   //  Input:
   //     addr     - register containing starting address
   //     count    - register containing element count
   //     tmp      - scratch register
   //
   //  The input registers are overwritten.
   //
   void gen_write_ref_array_post_barrier(Register addr, Register count,
                                    Register tmp) {
     BarrierSet* bs = Universe::heap()->barrier_set();
     switch (bs->kind()) {
       case BarrierSet::G1SATBCT:
       case BarrierSet::G1SATBCTLogging:
         {
           // Get some new fresh output registers.
           __ save_frame(0);
           __ mov(addr->after_save(), O0);
           __ call(CAST_FROM_FN_PTR(address, BarrierSet::static_write_ref_array_post));
           __ delayed()->mov(count->after_save(), O1);
           __ restore();
         }
         break;
       case BarrierSet::CardTableModRef:
       case BarrierSet::CardTableExtension:
         {
           CardTableModRefBS* ct = (CardTableModRefBS*)bs;
           assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust this code");
           assert_different_registers(addr, count, tmp);
           Label L_loop;
           __ sll_ptr(count, LogBytesPerHeapOop, count);
           __ sub(count, BytesPerHeapOop, count);
           __ add(count, addr, count);
           // Use two shifts to clear out those low order two bits! (Cannot opt. into 1.)
           __ srl_ptr(addr, CardTableModRefBS::card_shift, addr);
           __ srl_ptr(count, CardTableModRefBS::card_shift, count);
           __ sub(count, addr, count);
           AddressLiteral rs(ct->byte_map_base);
           __ set(rs, tmp);
         __ BIND(L_loop);
           __ stb(G0, tmp, addr);
           __ subcc(count, 1, count);
           __ brx(Assembler::greaterEqual, false, Assembler::pt, L_loop);
           __ delayed()->add(addr, 1, addr);
         }
         break;
       case BarrierSet::ModRef:
         break;
       default:
         ShouldNotReachHere();
     }
   }
   // Copy big chunks forward with shift
   //
   // Inputs:
   //   from      - source arrays
   //   to        - destination array aligned to 8-bytes
   //   count     - elements count to copy >= the count equivalent to 16 bytes
   //   count_dec - elements count's decrement equivalent to 16 bytes
   //   L_copy_bytes - copy exit label
   //
   void copy_16_bytes_forward_with_shift(Register from, Register to,
                      Register count, int count_dec, Label& L_copy_bytes) {
     Label L_loop, L_aligned_copy, L_copy_last_bytes;
     // if both arrays have the same alignment mod 8, do 8 bytes aligned copy
       __ andcc(from, 7, G1); // misaligned bytes
       __ br(Assembler::zero, false, Assembler::pt, L_aligned_copy);
       __ delayed()->nop();
     const Register left_shift  = G1; // left  shift bit counter
     const Register right_shift = G5; // right shift bit counter
       __ sll(G1, LogBitsPerByte, left_shift);
       __ mov(64, right_shift);
       __ sub(right_shift, left_shift, right_shift);
     //
     // Load 2 aligned 8-bytes chunks and use one from previous iteration
     // to form 2 aligned 8-bytes chunks to store.
     //
       __ deccc(count, count_dec); // Pre-decrement 'count'
       __ andn(from, 7, from);     // Align address
       __ ldx(from, 0, O3);
       __ inc(from, 8);
       __ align(OptoLoopAlignment);
     __ BIND(L_loop);
       __ ldx(from, 0, O4);
       __ deccc(count, count_dec); // Can we do next iteration after this one?
       __ ldx(from, 8, G4);
       __ inc(to, 16);
       __ inc(from, 16);
       __ sllx(O3, left_shift,  O3);
       __ srlx(O4, right_shift, G3);
       __ bset(G3, O3);
       __ stx(O3, to, -16);
       __ sllx(O4, left_shift,  O4);
       __ srlx(G4, right_shift, G3);
       __ bset(G3, O4);
       __ stx(O4, to, -8);
       __ brx(Assembler::greaterEqual, false, Assembler::pt, L_loop);
       __ delayed()->mov(G4, O3);
       __ inccc(count, count_dec>>1 ); // + 8 bytes
       __ brx(Assembler::negative, true, Assembler::pn, L_copy_last_bytes);
       __ delayed()->inc(count, count_dec>>1); // restore 'count'
       // copy 8 bytes, part of them already loaded in O3
       __ ldx(from, 0, O4);
       __ inc(to, 8);
       __ inc(from, 8);
       __ sllx(O3, left_shift,  O3);
       __ srlx(O4, right_shift, G3);
       __ bset(O3, G3);
       __ stx(G3, to, -8);
     __ BIND(L_copy_last_bytes);
       __ srl(right_shift, LogBitsPerByte, right_shift); // misaligned bytes
       __ br(Assembler::always, false, Assembler::pt, L_copy_bytes);
       __ delayed()->sub(from, right_shift, from);       // restore address
     __ BIND(L_aligned_copy);
   }
   // Copy big chunks backward with shift
   //
   // Inputs:
   //   end_from  - source arrays end address
   //   end_to    - destination array end address aligned to 8-bytes
   //   count     - elements count to copy >= the count equivalent to 16 bytes
   //   count_dec - elements count's decrement equivalent to 16 bytes
   //   L_aligned_copy - aligned copy exit label
   //   L_copy_bytes   - copy exit label
   //
   void copy_16_bytes_backward_with_shift(Register end_from, Register end_to,
                      Register count, int count_dec,
                      Label& L_aligned_copy, Label& L_copy_bytes) {
     Label L_loop, L_copy_last_bytes;
     // if both arrays have the same alignment mod 8, do 8 bytes aligned copy
       __ andcc(end_from, 7, G1); // misaligned bytes
       __ br(Assembler::zero, false, Assembler::pt, L_aligned_copy);
       __ delayed()->deccc(count, count_dec); // Pre-decrement 'count'
     const Register left_shift  = G1; // left  shift bit counter
     const Register right_shift = G5; // right shift bit counter
       __ sll(G1, LogBitsPerByte, left_shift);
       __ mov(64, right_shift);
       __ sub(right_shift, left_shift, right_shift);
     //
     // Load 2 aligned 8-bytes chunks and use one from previous iteration
     // to form 2 aligned 8-bytes chunks to store.
     //
       __ andn(end_from, 7, end_from);     // Align address
       __ ldx(end_from, 0, O3);
       __ align(OptoLoopAlignment);
     __ BIND(L_loop);
       __ ldx(end_from, -8, O4);
       __ deccc(count, count_dec); // Can we do next iteration after this one?
       __ ldx(end_from, -16, G4);
       __ dec(end_to, 16);
       __ dec(end_from, 16);
       __ srlx(O3, right_shift, O3);
       __ sllx(O4, left_shift,  G3);
       __ bset(G3, O3);
       __ stx(O3, end_to, 8);
       __ srlx(O4, right_shift, O4);
       __ sllx(G4, left_shift,  G3);
       __ bset(G3, O4);
       __ stx(O4, end_to, 0);
       __ brx(Assembler::greaterEqual, false, Assembler::pt, L_loop);
       __ delayed()->mov(G4, O3);
       __ inccc(count, count_dec>>1 ); // + 8 bytes
       __ brx(Assembler::negative, true, Assembler::pn, L_copy_last_bytes);
       __ delayed()->inc(count, count_dec>>1); // restore 'count'
       // copy 8 bytes, part of them already loaded in O3
       __ ldx(end_from, -8, O4);
       __ dec(end_to, 8);
       __ dec(end_from, 8);
       __ srlx(O3, right_shift, O3);
       __ sllx(O4, left_shift,  G3);
       __ bset(O3, G3);
       __ stx(G3, end_to, 0);
     __ BIND(L_copy_last_bytes);
       __ srl(left_shift, LogBitsPerByte, left_shift);    // misaligned bytes
       __ br(Assembler::always, false, Assembler::pt, L_copy_bytes);
       __ delayed()->add(end_from, left_shift, end_from); // restore address
   }
   //
   //  Generate stub for disjoint byte copy.  If "aligned" is true, the
   //  "from" and "to" addresses are assumed to be heapword aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_disjoint_byte_copy(bool aligned, const char * name) {
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     Label L_skip_alignment, L_align;
     Label L_copy_byte, L_copy_byte_loop, L_exit;
     const Register from      = O0;   // source array address
     const Register to        = O1;   // destination array address
     const Register count     = O2;   // elements count
     const Register offset    = O5;   // offset from start of arrays
     // O3, O4, G3, G4 are used as temp registers
     assert_clean_int(count, O3);     // Make sure 'count' is clean int.
     if (!aligned)  disjoint_byte_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)
     if (!aligned)  BLOCK_COMMENT("Entry:");
     // for short arrays, just do single element copy
     __ cmp(count, 23); // 16 + 7
     __ brx(Assembler::less, false, Assembler::pn, L_copy_byte);
     __ delayed()->mov(G0, offset);
     if (aligned) {
       // 'aligned' == true when it is known statically during compilation
       // of this arraycopy call site that both 'from' and 'to' addresses
       // are HeapWordSize aligned (see LibraryCallKit::basictype2arraycopy()).
       //
       // Aligned arrays have 4 bytes alignment in 32-bits VM
       // and 8 bytes - in 64-bits VM. So we do it only for 32-bits VM
       //
 #ifndef _LP64
       // copy a 4-bytes word if necessary to align 'to' to 8 bytes
       __ andcc(to, 7, G0);
       __ br(Assembler::zero, false, Assembler::pn, L_skip_alignment);
       __ delayed()->ld(from, 0, O3);
       __ inc(from, 4);
       __ inc(to, 4);
       __ dec(count, 4);
       __ st(O3, to, -4);
     __ BIND(L_skip_alignment);
 #endif
     } else {
       // copy bytes to align 'to' on 8 byte boundary
       __ andcc(to, 7, G1); // misaligned bytes
       __ br(Assembler::zero, false, Assembler::pt, L_skip_alignment);
       __ delayed()->neg(G1);
       __ inc(G1, 8);       // bytes need to copy to next 8-bytes alignment
       __ sub(count, G1, count);
     __ BIND(L_align);
       __ ldub(from, 0, O3);
       __ deccc(G1);
       __ inc(from);
       __ stb(O3, to, 0);
       __ br(Assembler::notZero, false, Assembler::pt, L_align);
       __ delayed()->inc(to);
     __ BIND(L_skip_alignment);
     }
 #ifdef _LP64
     if (!aligned)
 #endif
     {
       // Copy with shift 16 bytes per iteration if arrays do not have
       // the same alignment mod 8, otherwise fall through to the next
       // code for aligned copy.
       // The compare above (count >= 23) guarantes 'count' >= 16 bytes.
       // Also jump over aligned copy after the copy with shift completed.
       copy_16_bytes_forward_with_shift(from, to, count, 16, L_copy_byte);
     }
     // Both array are 8 bytes aligned, copy 16 bytes at a time
       __ and3(count, 7, G4); // Save count
       __ srl(count, 3, count);
      generate_disjoint_long_copy_core(aligned);
       __ mov(G4, count);     // Restore count
     // copy tailing bytes
     __ BIND(L_copy_byte);
       __ br_zero(Assembler::zero, false, Assembler::pt, count, L_exit);
       __ delayed()->nop();
       __ align(OptoLoopAlignment);
     __ BIND(L_copy_byte_loop);
       __ ldub(from, offset, O3);
       __ deccc(count);
       __ stb(O3, to, offset);
       __ brx(Assembler::notZero, false, Assembler::pt, L_copy_byte_loop);
       __ delayed()->inc(offset);
     __ BIND(L_exit);
       // O3, O4 are used as temp registers
       inc_counter_np(SharedRuntime::_jbyte_array_copy_ctr, O3, O4);
       __ retl();
       __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   //
   //  Generate stub for conjoint byte copy.  If "aligned" is true, the
   //  "from" and "to" addresses are assumed to be heapword aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_conjoint_byte_copy(bool aligned, const char * name) {
     // Do reverse copy.
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     address nooverlap_target = aligned ?
         StubRoutines::arrayof_jbyte_disjoint_arraycopy() :
         disjoint_byte_copy_entry;
     Label L_skip_alignment, L_align, L_aligned_copy;
     Label L_copy_byte, L_copy_byte_loop, L_exit;
     const Register from      = O0;   // source array address
     const Register to        = O1;   // destination array address
     const Register count     = O2;   // elements count
     const Register end_from  = from; // source array end address
     const Register end_to    = to;   // destination array end address
     assert_clean_int(count, O3);     // Make sure 'count' is clean int.
     if (!aligned)  byte_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)
     if (!aligned)  BLOCK_COMMENT("Entry:");
     array_overlap_test(nooverlap_target, 0);
     __ add(to, count, end_to);       // offset after last copied element
     // for short arrays, just do single element copy
     __ cmp(count, 23); // 16 + 7
     __ brx(Assembler::less, false, Assembler::pn, L_copy_byte);
     __ delayed()->add(from, count, end_from);
     {
       // Align end of arrays since they could be not aligned even
       // when arrays itself are aligned.
       // copy bytes to align 'end_to' on 8 byte boundary
       __ andcc(end_to, 7, G1); // misaligned bytes
       __ br(Assembler::zero, false, Assembler::pt, L_skip_alignment);
       __ delayed()->nop();
       __ sub(count, G1, count);
     __ BIND(L_align);
       __ dec(end_from);
       __ dec(end_to);
       __ ldub(end_from, 0, O3);
       __ deccc(G1);
       __ brx(Assembler::notZero, false, Assembler::pt, L_align);
       __ delayed()->stb(O3, end_to, 0);
     __ BIND(L_skip_alignment);
     }
 #ifdef _LP64
     if (aligned) {
       // Both arrays are aligned to 8-bytes in 64-bits VM.
       // The 'count' is decremented in copy_16_bytes_backward_with_shift()
       // in unaligned case.
       __ dec(count, 16);
     } else
 #endif
     {
       // Copy with shift 16 bytes per iteration if arrays do not have
       // the same alignment mod 8, otherwise jump to the next
       // code for aligned copy (and substracting 16 from 'count' before jump).
       // The compare above (count >= 11) guarantes 'count' >= 16 bytes.
       // Also jump over aligned copy after the copy with shift completed.
       copy_16_bytes_backward_with_shift(end_from, end_to, count, 16,
                                         L_aligned_copy, L_copy_byte);
     }
     // copy 4 elements (16 bytes) at a time
       __ align(OptoLoopAlignment);
     __ BIND(L_aligned_copy);
       __ dec(end_from, 16);
       __ ldx(end_from, 8, O3);
       __ ldx(end_from, 0, O4);
       __ dec(end_to, 16);
       __ deccc(count, 16);
       __ stx(O3, end_to, 8);
       __ brx(Assembler::greaterEqual, false, Assembler::pt, L_aligned_copy);
       __ delayed()->stx(O4, end_to, 0);
       __ inc(count, 16);
     // copy 1 element (2 bytes) at a time
     __ BIND(L_copy_byte);
       __ br_zero(Assembler::zero, false, Assembler::pt, count, L_exit);
       __ delayed()->nop();
       __ align(OptoLoopAlignment);
     __ BIND(L_copy_byte_loop);
       __ dec(end_from);
       __ dec(end_to);
       __ ldub(end_from, 0, O4);
       __ deccc(count);
       __ brx(Assembler::greater, false, Assembler::pt, L_copy_byte_loop);
       __ delayed()->stb(O4, end_to, 0);
     __ BIND(L_exit);
     // O3, O4 are used as temp registers
     inc_counter_np(SharedRuntime::_jbyte_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   //
   //  Generate stub for disjoint short copy.  If "aligned" is true, the
   //  "from" and "to" addresses are assumed to be heapword aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_disjoint_short_copy(bool aligned, const char * name) {
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     Label L_skip_alignment, L_skip_alignment2;
     Label L_copy_2_bytes, L_copy_2_bytes_loop, L_exit;
     const Register from      = O0;   // source array address
     const Register to        = O1;   // destination array address
     const Register count     = O2;   // elements count
     const Register offset    = O5;   // offset from start of arrays
     // O3, O4, G3, G4 are used as temp registers
     assert_clean_int(count, O3);     // Make sure 'count' is clean int.
     if (!aligned)  disjoint_short_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)
     if (!aligned)  BLOCK_COMMENT("Entry:");
     // for short arrays, just do single element copy
     __ cmp(count, 11); // 8 + 3  (22 bytes)
     __ brx(Assembler::less, false, Assembler::pn, L_copy_2_bytes);
     __ delayed()->mov(G0, offset);
     if (aligned) {
       // 'aligned' == true when it is known statically during compilation
       // of this arraycopy call site that both 'from' and 'to' addresses
       // are HeapWordSize aligned (see LibraryCallKit::basictype2arraycopy()).
       //
       // Aligned arrays have 4 bytes alignment in 32-bits VM
       // and 8 bytes - in 64-bits VM.
       //
 #ifndef _LP64
       // copy a 2-elements word if necessary to align 'to' to 8 bytes
       __ andcc(to, 7, G0);
       __ br(Assembler::zero, false, Assembler::pt, L_skip_alignment);
       __ delayed()->ld(from, 0, O3);
       __ inc(from, 4);
       __ inc(to, 4);
       __ dec(count, 2);
       __ st(O3, to, -4);
     __ BIND(L_skip_alignment);
 #endif
     } else {
       // copy 1 element if necessary to align 'to' on an 4 bytes
       __ andcc(to, 3, G0);
       __ br(Assembler::zero, false, Assembler::pt, L_skip_alignment);
       __ delayed()->lduh(from, 0, O3);
       __ inc(from, 2);
       __ inc(to, 2);
       __ dec(count);
       __ sth(O3, to, -2);
     __ BIND(L_skip_alignment);
       // copy 2 elements to align 'to' on an 8 byte boundary
       __ andcc(to, 7, G0);
       __ br(Assembler::zero, false, Assembler::pn, L_skip_alignment2);
       __ delayed()->lduh(from, 0, O3);
       __ dec(count, 2);
       __ lduh(from, 2, O4);
       __ inc(from, 4);
       __ inc(to, 4);
       __ sth(O3, to, -4);
       __ sth(O4, to, -2);
     __ BIND(L_skip_alignment2);
     }
 #ifdef _LP64
     if (!aligned)
 #endif
     {
       // Copy with shift 16 bytes per iteration if arrays do not have
       // the same alignment mod 8, otherwise fall through to the next
       // code for aligned copy.
       // The compare above (count >= 11) guarantes 'count' >= 16 bytes.
       // Also jump over aligned copy after the copy with shift completed.
       copy_16_bytes_forward_with_shift(from, to, count, 8, L_copy_2_bytes);
     }
     // Both array are 8 bytes aligned, copy 16 bytes at a time
       __ and3(count, 3, G4); // Save
       __ srl(count, 2, count);
      generate_disjoint_long_copy_core(aligned);
       __ mov(G4, count); // restore
     // copy 1 element at a time
     __ BIND(L_copy_2_bytes);
       __ br_zero(Assembler::zero, false, Assembler::pt, count, L_exit);
       __ delayed()->nop();
       __ align(OptoLoopAlignment);
     __ BIND(L_copy_2_bytes_loop);
       __ lduh(from, offset, O3);
       __ deccc(count);
       __ sth(O3, to, offset);
       __ brx(Assembler::notZero, false, Assembler::pt, L_copy_2_bytes_loop);
       __ delayed()->inc(offset, 2);
     __ BIND(L_exit);
       // O3, O4 are used as temp registers
       inc_counter_np(SharedRuntime::_jshort_array_copy_ctr, O3, O4);
       __ retl();
       __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   //
   //  Generate stub for conjoint short copy.  If "aligned" is true, the
   //  "from" and "to" addresses are assumed to be heapword aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_conjoint_short_copy(bool aligned, const char * name) {
     // Do reverse copy.
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     address nooverlap_target = aligned ?
         StubRoutines::arrayof_jshort_disjoint_arraycopy() :
         disjoint_short_copy_entry;
     Label L_skip_alignment, L_skip_alignment2, L_aligned_copy;
     Label L_copy_2_bytes, L_copy_2_bytes_loop, L_exit;
     const Register from      = O0;   // source array address
     const Register to        = O1;   // destination array address
     const Register count     = O2;   // elements count
     const Register end_from  = from; // source array end address
     const Register end_to    = to;   // destination array end address
     const Register byte_count = O3;  // bytes count to copy
     assert_clean_int(count, O3);     // Make sure 'count' is clean int.
     if (!aligned)  short_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)
     if (!aligned)  BLOCK_COMMENT("Entry:");
     array_overlap_test(nooverlap_target, 1);
     __ sllx(count, LogBytesPerShort, byte_count);
     __ add(to, byte_count, end_to);  // offset after last copied element
     // for short arrays, just do single element copy
     __ cmp(count, 11); // 8 + 3  (22 bytes)
     __ brx(Assembler::less, false, Assembler::pn, L_copy_2_bytes);
     __ delayed()->add(from, byte_count, end_from);
     {
       // Align end of arrays since they could be not aligned even
       // when arrays itself are aligned.
       // copy 1 element if necessary to align 'end_to' on an 4 bytes
       __ andcc(end_to, 3, G0);
       __ br(Assembler::zero, false, Assembler::pt, L_skip_alignment);
       __ delayed()->lduh(end_from, -2, O3);
       __ dec(end_from, 2);
       __ dec(end_to, 2);
       __ dec(count);
       __ sth(O3, end_to, 0);
     __ BIND(L_skip_alignment);
       // copy 2 elements to align 'end_to' on an 8 byte boundary
       __ andcc(end_to, 7, G0);
       __ br(Assembler::zero, false, Assembler::pn, L_skip_alignment2);
       __ delayed()->lduh(end_from, -2, O3);
       __ dec(count, 2);
       __ lduh(end_from, -4, O4);
       __ dec(end_from, 4);
       __ dec(end_to, 4);
       __ sth(O3, end_to, 2);
       __ sth(O4, end_to, 0);
     __ BIND(L_skip_alignment2);
     }
 #ifdef _LP64
     if (aligned) {
       // Both arrays are aligned to 8-bytes in 64-bits VM.
       // The 'count' is decremented in copy_16_bytes_backward_with_shift()
       // in unaligned case.
       __ dec(count, 8);
     } else
 #endif
     {
       // Copy with shift 16 bytes per iteration if arrays do not have
       // the same alignment mod 8, otherwise jump to the next
       // code for aligned copy (and substracting 8 from 'count' before jump).
       // The compare above (count >= 11) guarantes 'count' >= 16 bytes.
       // Also jump over aligned copy after the copy with shift completed.
       copy_16_bytes_backward_with_shift(end_from, end_to, count, 8,
                                         L_aligned_copy, L_copy_2_bytes);
     }
     // copy 4 elements (16 bytes) at a time
       __ align(OptoLoopAlignment);
     __ BIND(L_aligned_copy);
       __ dec(end_from, 16);
       __ ldx(end_from, 8, O3);
       __ ldx(end_from, 0, O4);
       __ dec(end_to, 16);
       __ deccc(count, 8);
       __ stx(O3, end_to, 8);
       __ brx(Assembler::greaterEqual, false, Assembler::pt, L_aligned_copy);
       __ delayed()->stx(O4, end_to, 0);
       __ inc(count, 8);
     // copy 1 element (2 bytes) at a time
     __ BIND(L_copy_2_bytes);
       __ br_zero(Assembler::zero, false, Assembler::pt, count, L_exit);
       __ delayed()->nop();
     __ BIND(L_copy_2_bytes_loop);
       __ dec(end_from, 2);
       __ dec(end_to, 2);
       __ lduh(end_from, 0, O4);
       __ deccc(count);
       __ brx(Assembler::greater, false, Assembler::pt, L_copy_2_bytes_loop);
       __ delayed()->sth(O4, end_to, 0);
     __ BIND(L_exit);
     // O3, O4 are used as temp registers
     inc_counter_np(SharedRuntime::_jshort_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   //
   //  Generate core code for disjoint int copy (and oop copy on 32-bit).
   //  If "aligned" is true, the "from" and "to" addresses are assumed
   //  to be heapword aligned.
   //
   // Arguments:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   void generate_disjoint_int_copy_core(bool aligned) {
     Label L_skip_alignment, L_aligned_copy;
     Label L_copy_16_bytes,  L_copy_4_bytes, L_copy_4_bytes_loop, L_exit;
     const Register from      = O0;   // source array address
     const Register to        = O1;   // destination array address
     const Register count     = O2;   // elements count
     const Register offset    = O5;   // offset from start of arrays
     // O3, O4, G3, G4 are used as temp registers
     // 'aligned' == true when it is known statically during compilation
     // of this arraycopy call site that both 'from' and 'to' addresses
     // are HeapWordSize aligned (see LibraryCallKit::basictype2arraycopy()).
     //
     // Aligned arrays have 4 bytes alignment in 32-bits VM
     // and 8 bytes - in 64-bits VM.
     //
 #ifdef _LP64
     if (!aligned)
 #endif
     {
       // The next check could be put under 'ifndef' since the code in
       // generate_disjoint_long_copy_core() has own checks and set 'offset'.
       // for short arrays, just do single element copy
       __ cmp(count, 5); // 4 + 1 (20 bytes)
       __ brx(Assembler::lessEqual, false, Assembler::pn, L_copy_4_bytes);
       __ delayed()->mov(G0, offset);
       // copy 1 element to align 'to' on an 8 byte boundary
       __ andcc(to, 7, G0);
       __ br(Assembler::zero, false, Assembler::pt, L_skip_alignment);
       __ delayed()->ld(from, 0, O3);
       __ inc(from, 4);
       __ inc(to, 4);
       __ dec(count);
       __ st(O3, to, -4);
     __ BIND(L_skip_alignment);
     // if arrays have same alignment mod 8, do 4 elements copy
       __ andcc(from, 7, G0);
       __ br(Assembler::zero, false, Assembler::pt, L_aligned_copy);
       __ delayed()->ld(from, 0, O3);
     //
     // Load 2 aligned 8-bytes chunks and use one from previous iteration
     // to form 2 aligned 8-bytes chunks to store.
     //
     // copy_16_bytes_forward_with_shift() is not used here since this
     // code is more optimal.
     // copy with shift 4 elements (16 bytes) at a time
       __ dec(count, 4);   // The cmp at the beginning guaranty count >= 4
       __ align(OptoLoopAlignment);
     __ BIND(L_copy_16_bytes);
       __ ldx(from, 4, O4);
       __ deccc(count, 4); // Can we do next iteration after this one?
       __ ldx(from, 12, G4);
       __ inc(to, 16);
       __ inc(from, 16);
       __ sllx(O3, 32, O3);
       __ srlx(O4, 32, G3);
       __ bset(G3, O3);
       __ stx(O3, to, -16);
       __ sllx(O4, 32, O4);
       __ srlx(G4, 32, G3);
       __ bset(G3, O4);
       __ stx(O4, to, -8);
       __ brx(Assembler::greaterEqual, false, Assembler::pt, L_copy_16_bytes);
       __ delayed()->mov(G4, O3);
       __ br(Assembler::always, false, Assembler::pt, L_copy_4_bytes);
       __ delayed()->inc(count, 4); // restore 'count'
     __ BIND(L_aligned_copy);
     }
     // copy 4 elements (16 bytes) at a time
       __ and3(count, 1, G4); // Save
       __ srl(count, 1, count);
      generate_disjoint_long_copy_core(aligned);
       __ mov(G4, count);     // Restore
     // copy 1 element at a time
     __ BIND(L_copy_4_bytes);
       __ br_zero(Assembler::zero, false, Assembler::pt, count, L_exit);
       __ delayed()->nop();
     __ BIND(L_copy_4_bytes_loop);
       __ ld(from, offset, O3);
       __ deccc(count);
       __ st(O3, to, offset);
       __ brx(Assembler::notZero, false, Assembler::pt, L_copy_4_bytes_loop);
       __ delayed()->inc(offset, 4);
     __ BIND(L_exit);
   }
   //
   //  Generate stub for disjoint int copy.  If "aligned" is true, the
   //  "from" and "to" addresses are assumed to be heapword aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_disjoint_int_copy(bool aligned, const char * name) {
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     const Register count = O2;
     assert_clean_int(count, O3);     // Make sure 'count' is clean int.
     if (!aligned)  disjoint_int_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)
     if (!aligned)  BLOCK_COMMENT("Entry:");
     generate_disjoint_int_copy_core(aligned);
     // O3, O4 are used as temp registers
     inc_counter_np(SharedRuntime::_jint_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   //
   //  Generate core code for conjoint int copy (and oop copy on 32-bit).
   //  If "aligned" is true, the "from" and "to" addresses are assumed
   //  to be heapword aligned.
   //
   // Arguments:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   void generate_conjoint_int_copy_core(bool aligned) {
     // Do reverse copy.
     Label L_skip_alignment, L_aligned_copy;
     Label L_copy_16_bytes,  L_copy_4_bytes, L_copy_4_bytes_loop, L_exit;
     const Register from      = O0;   // source array address
     const Register to        = O1;   // destination array address
     const Register count     = O2;   // elements count
     const Register end_from  = from; // source array end address
     const Register end_to    = to;   // destination array end address
     // O3, O4, O5, G3 are used as temp registers
     const Register byte_count = O3;  // bytes count to copy
       __ sllx(count, LogBytesPerInt, byte_count);
       __ add(to, byte_count, end_to); // offset after last copied element
       __ cmp(count, 5); // for short arrays, just do single element copy
       __ brx(Assembler::lessEqual, false, Assembler::pn, L_copy_4_bytes);
       __ delayed()->add(from, byte_count, end_from);
     // copy 1 element to align 'to' on an 8 byte boundary
       __ andcc(end_to, 7, G0);
       __ br(Assembler::zero, false, Assembler::pt, L_skip_alignment);
       __ delayed()->nop();
       __ dec(count);
       __ dec(end_from, 4);
       __ dec(end_to,   4);
       __ ld(end_from, 0, O4);
       __ st(O4, end_to, 0);
     __ BIND(L_skip_alignment);
     // Check if 'end_from' and 'end_to' has the same alignment.
       __ andcc(end_from, 7, G0);
       __ br(Assembler::zero, false, Assembler::pt, L_aligned_copy);
       __ delayed()->dec(count, 4); // The cmp at the start guaranty cnt >= 4
     // copy with shift 4 elements (16 bytes) at a time
     //
     // Load 2 aligned 8-bytes chunks and use one from previous iteration
     // to form 2 aligned 8-bytes chunks to store.
     //
       __ ldx(end_from, -4, O3);
       __ align(OptoLoopAlignment);
     __ BIND(L_copy_16_bytes);
       __ ldx(end_from, -12, O4);
       __ deccc(count, 4);
       __ ldx(end_from, -20, O5);
       __ dec(end_to, 16);
       __ dec(end_from, 16);
       __ srlx(O3, 32, O3);
       __ sllx(O4, 32, G3);
       __ bset(G3, O3);
       __ stx(O3, end_to, 8);
       __ srlx(O4, 32, O4);
       __ sllx(O5, 32, G3);
       __ bset(O4, G3);
       __ stx(G3, end_to, 0);
       __ brx(Assembler::greaterEqual, false, Assembler::pt, L_copy_16_bytes);
       __ delayed()->mov(O5, O3);
       __ br(Assembler::always, false, Assembler::pt, L_copy_4_bytes);
       __ delayed()->inc(count, 4);
     // copy 4 elements (16 bytes) at a time
       __ align(OptoLoopAlignment);
     __ BIND(L_aligned_copy);
       __ dec(end_from, 16);
       __ ldx(end_from, 8, O3);
       __ ldx(end_from, 0, O4);
       __ dec(end_to, 16);
       __ deccc(count, 4);
       __ stx(O3, end_to, 8);
       __ brx(Assembler::greaterEqual, false, Assembler::pt, L_aligned_copy);
       __ delayed()->stx(O4, end_to, 0);
       __ inc(count, 4);
     // copy 1 element (4 bytes) at a time
     __ BIND(L_copy_4_bytes);
       __ br_zero(Assembler::zero, false, Assembler::pt, count, L_exit);
       __ delayed()->nop();
     __ BIND(L_copy_4_bytes_loop);
       __ dec(end_from, 4);
       __ dec(end_to, 4);
       __ ld(end_from, 0, O4);
       __ deccc(count);
       __ brx(Assembler::greater, false, Assembler::pt, L_copy_4_bytes_loop);
       __ delayed()->st(O4, end_to, 0);
     __ BIND(L_exit);
   }
   //
   //  Generate stub for conjoint int copy.  If "aligned" is true, the
   //  "from" and "to" addresses are assumed to be heapword aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_conjoint_int_copy(bool aligned, const char * name) {
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     address nooverlap_target = aligned ?
         StubRoutines::arrayof_jint_disjoint_arraycopy() :
         disjoint_int_copy_entry;
     assert_clean_int(O2, O3);     // Make sure 'count' is clean int.
     if (!aligned)  int_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)
     if (!aligned)  BLOCK_COMMENT("Entry:");
     array_overlap_test(nooverlap_target, 2);
     generate_conjoint_int_copy_core(aligned);
     // O3, O4 are used as temp registers
     inc_counter_np(SharedRuntime::_jint_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   //
   //  Generate core code for disjoint long copy (and oop copy on 64-bit).
   //  "aligned" is ignored, because we must make the stronger
   //  assumption that both addresses are always 64-bit aligned.
   //
   // Arguments:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   // count -= 2;
   // if ( count >= 0 ) { // >= 2 elements
   //   if ( count > 6) { // >= 8 elements
   //     count -= 6; // original count - 8
   //     do {
   //       copy_8_elements;
   //       count -= 8;
   //     } while ( count >= 0 );
   //     count += 6;
   //   }
   //   if ( count >= 0 ) { // >= 2 elements
   //     do {
   //       copy_2_elements;
   //     } while ( (count=count-2) >= 0 );
   //   }
   // }
   // count += 2;
   // if ( count != 0 ) { // 1 element left
   //   copy_1_element;
   // }
   //
   void generate_disjoint_long_copy_core(bool aligned) {
     Label L_copy_8_bytes, L_copy_16_bytes, L_exit;
     const Register from    = O0;  // source array address
     const Register to      = O1;  // destination array address
     const Register count   = O2;  // elements count
     const Register offset0 = O4;  // element offset
     const Register offset8 = O5;  // next element offset
       __ deccc(count, 2);
       __ mov(G0, offset0);   // offset from start of arrays (0)
       __ brx(Assembler::negative, false, Assembler::pn, L_copy_8_bytes );
       __ delayed()->add(offset0, 8, offset8);
     // Copy by 64 bytes chunks
     Label L_copy_64_bytes;
     const Register from64 = O3;  // source address
     const Register to64   = G3;  // destination address
       __ subcc(count, 6, O3);
       __ brx(Assembler::negative, false, Assembler::pt, L_copy_16_bytes );
       __ delayed()->mov(to,   to64);
       // Now we can use O4(offset0), O5(offset8) as temps
       __ mov(O3, count);
       __ mov(from, from64);
       __ align(OptoLoopAlignment);
     __ BIND(L_copy_64_bytes);
       for( int off = 0; off < 64; off += 16 ) {
         __ ldx(from64,  off+0, O4);
         __ ldx(from64,  off+8, O5);
         __ stx(O4, to64,  off+0);
         __ stx(O5, to64,  off+8);
       }
       __ deccc(count, 8);
       __ inc(from64, 64);
       __ brx(Assembler::greaterEqual, false, Assembler::pt, L_copy_64_bytes);
       __ delayed()->inc(to64, 64);
       // Restore O4(offset0), O5(offset8)
       __ sub(from64, from, offset0);
       __ inccc(count, 6);
       __ brx(Assembler::negative, false, Assembler::pn, L_copy_8_bytes );
       __ delayed()->add(offset0, 8, offset8);
       // Copy by 16 bytes chunks
       __ align(OptoLoopAlignment);
     __ BIND(L_copy_16_bytes);
       __ ldx(from, offset0, O3);
       __ ldx(from, offset8, G3);
       __ deccc(count, 2);
       __ stx(O3, to, offset0);
       __ inc(offset0, 16);
       __ stx(G3, to, offset8);
       __ brx(Assembler::greaterEqual, false, Assembler::pt, L_copy_16_bytes);
       __ delayed()->inc(offset8, 16);
       // Copy last 8 bytes
     __ BIND(L_copy_8_bytes);
       __ inccc(count, 2);
       __ brx(Assembler::zero, true, Assembler::pn, L_exit );
       __ delayed()->mov(offset0, offset8); // Set O5 used by other stubs
       __ ldx(from, offset0, O3);
       __ stx(O3, to, offset0);
     __ BIND(L_exit);
   }
   //
   //  Generate stub for disjoint long copy.
   //  "aligned" is ignored, because we must make the stronger
   //  assumption that both addresses are always 64-bit aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_disjoint_long_copy(bool aligned, const char * name) {
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     assert_clean_int(O2, O3);     // Make sure 'count' is clean int.
     if (!aligned)  disjoint_long_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)
     if (!aligned)  BLOCK_COMMENT("Entry:");
     generate_disjoint_long_copy_core(aligned);
     // O3, O4 are used as temp registers
     inc_counter_np(SharedRuntime::_jlong_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   //
   //  Generate core code for conjoint long copy (and oop copy on 64-bit).
   //  "aligned" is ignored, because we must make the stronger
   //  assumption that both addresses are always 64-bit aligned.
   //
   // Arguments:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   void generate_conjoint_long_copy_core(bool aligned) {
     // Do reverse copy.
     Label L_copy_8_bytes, L_copy_16_bytes, L_exit;
     const Register from    = O0;  // source array address
     const Register to      = O1;  // destination array address
     const Register count   = O2;  // elements count
     const Register offset8 = O4;  // element offset
     const Register offset0 = O5;  // previous element offset
       __ subcc(count, 1, count);
       __ brx(Assembler::lessEqual, false, Assembler::pn, L_copy_8_bytes );
       __ delayed()->sllx(count, LogBytesPerLong, offset8);
       __ sub(offset8, 8, offset0);
       __ align(OptoLoopAlignment);
     __ BIND(L_copy_16_bytes);
       __ ldx(from, offset8, O2);
       __ ldx(from, offset0, O3);
       __ stx(O2, to, offset8);
       __ deccc(offset8, 16);      // use offset8 as counter
       __ stx(O3, to, offset0);
       __ brx(Assembler::greater, false, Assembler::pt, L_copy_16_bytes);
       __ delayed()->dec(offset0, 16);
     __ BIND(L_copy_8_bytes);
       __ brx(Assembler::negative, false, Assembler::pn, L_exit );
       __ delayed()->nop();
       __ ldx(from, 0, O3);
       __ stx(O3, to, 0);
     __ BIND(L_exit);
   }
   //  Generate stub for conjoint long copy.
   //  "aligned" is ignored, because we must make the stronger
   //  assumption that both addresses are always 64-bit aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_conjoint_long_copy(bool aligned, const char * name) {
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     assert(!aligned, "usage");
     address nooverlap_target = disjoint_long_copy_entry;
     assert_clean_int(O2, O3);     // Make sure 'count' is clean int.
     if (!aligned)  long_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)
     if (!aligned)  BLOCK_COMMENT("Entry:");
     array_overlap_test(nooverlap_target, 3);
     generate_conjoint_long_copy_core(aligned);
     // O3, O4 are used as temp registers
     inc_counter_np(SharedRuntime::_jlong_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   //  Generate stub for disjoint oop copy.  If "aligned" is true, the
   //  "from" and "to" addresses are assumed to be heapword aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_disjoint_oop_copy(bool aligned, const char * name) {
     const Register from  = O0;  // source array address
     const Register to    = O1;  // destination array address
     const Register count = O2;  // elements count
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     assert_clean_int(count, O3);     // Make sure 'count' is clean int.
     if (!aligned)  disjoint_oop_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here
     if (!aligned)  BLOCK_COMMENT("Entry:");
     // save arguments for barrier generation
     __ mov(to, G1);
     __ mov(count, G5);
     gen_write_ref_array_pre_barrier(G1, G5);
   #ifdef _LP64
     assert_clean_int(count, O3);     // Make sure 'count' is clean int.
     if (UseCompressedOops) {
       generate_disjoint_int_copy_core(aligned);
     } else {
       generate_disjoint_long_copy_core(aligned);
     }
   #else
     generate_disjoint_int_copy_core(aligned);
   #endif
     // O0 is used as temp register
     gen_write_ref_array_post_barrier(G1, G5, O0);
     // O3, O4 are used as temp registers
     inc_counter_np(SharedRuntime::_oop_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   //  Generate stub for conjoint oop copy.  If "aligned" is true, the
   //  "from" and "to" addresses are assumed to be heapword aligned.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //
   address generate_conjoint_oop_copy(bool aligned, const char * name) {
     const Register from  = O0;  // source array address
     const Register to    = O1;  // destination array address
     const Register count = O2;  // elements count
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     assert_clean_int(count, O3);     // Make sure 'count' is clean int.
     if (!aligned)  oop_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here
     if (!aligned)  BLOCK_COMMENT("Entry:");
     // save arguments for barrier generation
     __ mov(to, G1);
     __ mov(count, G5);
     gen_write_ref_array_pre_barrier(G1, G5);
     address nooverlap_target = aligned ?
         StubRoutines::arrayof_oop_disjoint_arraycopy() :
         disjoint_oop_copy_entry;
     array_overlap_test(nooverlap_target, LogBytesPerHeapOop);
   #ifdef _LP64
     if (UseCompressedOops) {
       generate_conjoint_int_copy_core(aligned);
     } else {
       generate_conjoint_long_copy_core(aligned);
     }
   #else
     generate_conjoint_int_copy_core(aligned);
   #endif
     // O0 is used as temp register
     gen_write_ref_array_post_barrier(G1, G5, O0);
     // O3, O4 are used as temp registers
     inc_counter_np(SharedRuntime::_oop_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->mov(G0, O0); // return 0
     return start;
   }
   // Helper for generating a dynamic type check.
   // Smashes only the given temp registers.
   void generate_type_check(Register sub_klass,
                            Register super_check_offset,
                            Register super_klass,
                            Register temp,
                            Label& L_success) {
     assert_different_registers(sub_klass, super_check_offset, super_klass, temp);
     BLOCK_COMMENT("type_check:");
     Label L_miss, L_pop_to_miss;
     assert_clean_int(super_check_offset, temp);
     __ check_klass_subtype_fast_path(sub_klass, super_klass, temp, noreg,
                                      &L_success, &L_miss, NULL,
                                      super_check_offset);
     BLOCK_COMMENT("type_check_slow_path:");
     __ save_frame(0);
     __ check_klass_subtype_slow_path(sub_klass->after_save(),
                                      super_klass->after_save(),
                                      L0, L1, L2, L4,
                                      NULL, &L_pop_to_miss);
     __ ba(false, L_success);
     __ delayed()->restore();
     __ bind(L_pop_to_miss);
     __ restore();
     // Fall through on failure!
     __ BIND(L_miss);
   }
   //  Generate stub for checked oop copy.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 treated as signed
   //      ckoff: O3 (super_check_offset)
   //      ckval: O4 (super_klass)
   //      ret:   O0 zero for success; (-1^K) where K is partial transfer count
   //
   address generate_checkcast_copy(const char* name) {
     const Register O0_from   = O0;      // source array address
     const Register O1_to     = O1;      // destination array address
     const Register O2_count  = O2;      // elements count
     const Register O3_ckoff  = O3;      // super_check_offset
     const Register O4_ckval  = O4;      // super_klass
     const Register O5_offset = O5;      // loop var, with stride wordSize
     const Register G1_remain = G1;      // loop var, with stride -1
     const Register G3_oop    = G3;      // actual oop copied
     const Register G4_klass  = G4;      // oop._klass
     const Register G5_super  = G5;      // oop._klass._primary_supers[ckval]
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     gen_write_ref_array_pre_barrier(O1, O2);
 #ifdef ASSERT
     // We sometimes save a frame (see generate_type_check below).
     // If this will cause trouble, let's fail now instead of later.
     __ save_frame(0);
     __ restore();
 #endif
 #ifdef ASSERT
     // caller guarantees that the arrays really are different
     // otherwise, we would have to make conjoint checks
     { Label L;
       __ mov(O3, G1);           // spill: overlap test smashes O3
       __ mov(O4, G4);           // spill: overlap test smashes O4
       array_overlap_test(L, LogBytesPerHeapOop);
       __ stop("checkcast_copy within a single array");
       __ bind(L);
       __ mov(G1, O3);
       __ mov(G4, O4);
     }
 #endif //ASSERT
     assert_clean_int(O2_count, G1);     // Make sure 'count' is clean int.
     checkcast_copy_entry = __ pc();
     // caller can pass a 64-bit byte count here (from generic stub)
     BLOCK_COMMENT("Entry:");
     Label load_element, store_element, do_card_marks, fail, done;
     __ addcc(O2_count, 0, G1_remain);   // initialize loop index, and test it
     __ brx(Assembler::notZero, false, Assembler::pt, load_element);
     __ delayed()->mov(G0, O5_offset);   // offset from start of arrays
     // Empty array:  Nothing to do.
     inc_counter_np(SharedRuntime::_checkcast_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->set(0, O0);           // return 0 on (trivial) success
     // ======== begin loop ========
     // (Loop is rotated; its entry is load_element.)
     // Loop variables:
     //   (O5 = 0; ; O5 += wordSize) --- offset from src, dest arrays
     //   (O2 = len; O2 != 0; O2--) --- number of oops *remaining*
     //   G3, G4, G5 --- current oop, oop.klass, oop.klass.super
     __ align(OptoLoopAlignment);
     __ BIND(store_element);
     __ deccc(G1_remain);                // decrement the count
     __ store_heap_oop(G3_oop, O1_to, O5_offset); // store the oop
     __ inc(O5_offset, heapOopSize);     // step to next offset
     __ brx(Assembler::zero, true, Assembler::pt, do_card_marks);
     __ delayed()->set(0, O0);           // return -1 on success
     // ======== loop entry is here ========
     __ BIND(load_element);
     __ load_heap_oop(O0_from, O5_offset, G3_oop);  // load the oop
     __ br_null(G3_oop, true, Assembler::pt, store_element);
     __ delayed()->nop();
     __ load_klass(G3_oop, G4_klass); // query the object klass
     generate_type_check(G4_klass, O3_ckoff, O4_ckval, G5_super,
                         // branch to this on success:
                         store_element);
     // ======== end loop ========
     // It was a real error; we must depend on the caller to finish the job.
     // Register G1 has number of *remaining* oops, O2 number of *total* oops.
     // Emit GC store barriers for the oops we have copied (O2 minus G1),
     // and report their number to the caller.
     __ BIND(fail);
     __ subcc(O2_count, G1_remain, O2_count);
     __ brx(Assembler::zero, false, Assembler::pt, done);
     __ delayed()->not1(O2_count, O0);   // report (-1^K) to caller
     __ BIND(do_card_marks);
     gen_write_ref_array_post_barrier(O1_to, O2_count, O3);   // store check on O1[0..O2]
     __ BIND(done);
     inc_counter_np(SharedRuntime::_checkcast_array_copy_ctr, O3, O4);
     __ retl();
     __ delayed()->nop();             // return value in 00
     return start;
   }
   //  Generate 'unsafe' array copy stub
   //  Though just as safe as the other stubs, it takes an unscaled
   //  size_t argument instead of an element count.
   //
   // Arguments for generated stub:
   //      from:  O0
   //      to:    O1
   //      count: O2 byte count, treated as ssize_t, can be zero
   //
   // Examines the alignment of the operands and dispatches
   // to a long, int, short, or byte copy loop.
   //
   address generate_unsafe_copy(const char* name) {
     const Register O0_from   = O0;      // source array address
     const Register O1_to     = O1;      // destination array address
     const Register O2_count  = O2;      // elements count
     const Register G1_bits   = G1;      // test copy of low bits
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     // bump this on entry, not on exit:
     inc_counter_np(SharedRuntime::_unsafe_array_copy_ctr, G1, G3);
     __ or3(O0_from, O1_to, G1_bits);
     __ or3(O2_count,       G1_bits, G1_bits);
     __ btst(BytesPerLong-1, G1_bits);
     __ br(Assembler::zero, true, Assembler::pt,
           long_copy_entry, relocInfo::runtime_call_type);
     // scale the count on the way out:
     __ delayed()->srax(O2_count, LogBytesPerLong, O2_count);
     __ btst(BytesPerInt-1, G1_bits);
     __ br(Assembler::zero, true, Assembler::pt,
           int_copy_entry, relocInfo::runtime_call_type);
     // scale the count on the way out:
     __ delayed()->srax(O2_count, LogBytesPerInt, O2_count);
     __ btst(BytesPerShort-1, G1_bits);
     __ br(Assembler::zero, true, Assembler::pt,
           short_copy_entry, relocInfo::runtime_call_type);
     // scale the count on the way out:
     __ delayed()->srax(O2_count, LogBytesPerShort, O2_count);
     __ br(Assembler::always, false, Assembler::pt,
           byte_copy_entry, relocInfo::runtime_call_type);
     __ delayed()->nop();
     return start;
   }
   // Perform range checks on the proposed arraycopy.
   // Kills the two temps, but nothing else.
   // Also, clean the sign bits of src_pos and dst_pos.
   void arraycopy_range_checks(Register src,     // source array oop (O0)
                               Register src_pos, // source position (O1)
                               Register dst,     // destination array oo (O2)
                               Register dst_pos, // destination position (O3)
                               Register length,  // length of copy (O4)
                               Register temp1, Register temp2,
                               Label& L_failed) {
     BLOCK_COMMENT("arraycopy_range_checks:");
     //  if (src_pos + length > arrayOop(src)->length() ) FAIL;
     const Register array_length = temp1;  // scratch
     const Register end_pos      = temp2;  // scratch
     // Note:  This next instruction may be in the delay slot of a branch:
     __ add(length, src_pos, end_pos);  // src_pos + length
     __ lduw(src, arrayOopDesc::length_offset_in_bytes(), array_length);
     __ cmp(end_pos, array_length);
     __ br(Assembler::greater, false, Assembler::pn, L_failed);
     //  if (dst_pos + length > arrayOop(dst)->length() ) FAIL;
     __ delayed()->add(length, dst_pos, end_pos); // dst_pos + length
     __ lduw(dst, arrayOopDesc::length_offset_in_bytes(), array_length);
     __ cmp(end_pos, array_length);
     __ br(Assembler::greater, false, Assembler::pn, L_failed);
     // Have to clean up high 32-bits of 'src_pos' and 'dst_pos'.
     // Move with sign extension can be used since they are positive.
     __ delayed()->signx(src_pos, src_pos);
     __ signx(dst_pos, dst_pos);
     BLOCK_COMMENT("arraycopy_range_checks done");
   }
   //
   //  Generate generic array copy stubs
   //
   //  Input:
   //    O0    -  src oop
   //    O1    -  src_pos
   //    O2    -  dst oop
   //    O3    -  dst_pos
   //    O4    -  element count
   //
   //  Output:
   //    O0 ==  0  -  success
   //    O0 == -1  -  need to call System.arraycopy
   //
   address generate_generic_copy(const char *name) {
     Label L_failed, L_objArray;
     // Input registers
     const Register src      = O0;  // source array oop
     const Register src_pos  = O1;  // source position
     const Register dst      = O2;  // destination array oop
     const Register dst_pos  = O3;  // destination position
     const Register length   = O4;  // elements count
     // registers used as temp
     const Register G3_src_klass = G3; // source array klass
     const Register G4_dst_klass = G4; // destination array klass
     const Register G5_lh        = G5; // layout handler
     const Register O5_temp      = O5;
     __ align(CodeEntryAlignment);
     StubCodeMark mark(this, "StubRoutines", name);
     address start = __ pc();
     // bump this on entry, not on exit:
     inc_counter_np(SharedRuntime::_generic_array_copy_ctr, G1, G3);
     // In principle, the int arguments could be dirty.
     //assert_clean_int(src_pos, G1);
     //assert_clean_int(dst_pos, G1);
     //assert_clean_int(length, G1);
     //-----------------------------------------------------------------------
     // Assembler stubs will be used for this call to arraycopy
     // if the following conditions are met:
     //
     // (1) src and dst must not be null.
     // (2) src_pos must not be negative.
     // (3) dst_pos must not be negative.
     // (4) length  must not be negative.
     // (5) src klass and dst klass should be the same and not NULL.
     // (6) src and dst should be arrays.
     // (7) src_pos + length must not exceed length of src.
     // (8) dst_pos + length must not exceed length of dst.
     BLOCK_COMMENT("arraycopy initial argument checks");
     //  if (src == NULL) return -1;
     __ br_null(src, false, Assembler::pn, L_failed);
     //  if (src_pos < 0) return -1;
     __ delayed()->tst(src_pos);
     __ br(Assembler::negative, false, Assembler::pn, L_failed);
     __ delayed()->nop();
     //  if (dst == NULL) return -1;
     __ br_null(dst, false, Assembler::pn, L_failed);
     //  if (dst_pos < 0) return -1;
     __ delayed()->tst(dst_pos);
     __ br(Assembler::negative, false, Assembler::pn, L_failed);
     //  if (length < 0) return -1;
     __ delayed()->tst(length);
     __ br(Assembler::negative, false, Assembler::pn, L_failed);
     BLOCK_COMMENT("arraycopy argument klass checks");
     //  get src->klass()
     if (UseCompressedOops) {
       __ delayed()->nop(); // ??? not good
       __ load_klass(src, G3_src_klass);
     } else {
       __ delayed()->ld_ptr(src, oopDesc::klass_offset_in_bytes(), G3_src_klass);
     }
 #ifdef ASSERT
     //  assert(src->klass() != NULL);
     BLOCK_COMMENT("assert klasses not null");
     { Label L_a, L_b;
       __ br_notnull(G3_src_klass, false, Assembler::pt, L_b); // it is broken if klass is NULL
       __ delayed()->nop();
       __ bind(L_a);
       __ stop("broken null klass");
       __ bind(L_b);
       __ load_klass(dst, G4_dst_klass);
       __ br_null(G4_dst_klass, false, Assembler::pn, L_a); // this would be broken also
       __ delayed()->mov(G0, G4_dst_klass);      // scribble the temp
       BLOCK_COMMENT("assert done");
     }
 #endif
     // Load layout helper
     //
     //  |array_tag|     | header_size | element_type |     |log2_element_size|
     // 32        30    24            16              8     2                 0
     //
     //   array_tag: typeArray = 0x3, objArray = 0x2, non-array = 0x0
     //
     int lh_offset = klassOopDesc::header_size() * HeapWordSize +
                     Klass::layout_helper_offset_in_bytes();
     // Load 32-bits signed value. Use br() instruction with it to check icc.
     __ lduw(G3_src_klass, lh_offset, G5_lh);
     if (UseCompressedOops) {
       __ load_klass(dst, G4_dst_klass);
     }
     // Handle objArrays completely differently...
     juint objArray_lh = Klass::array_layout_helper(T_OBJECT);
     __ set(objArray_lh, O5_temp);
     __ cmp(G5_lh,       O5_temp);
     __ br(Assembler::equal, false, Assembler::pt, L_objArray);
     if (UseCompressedOops) {
       __ delayed()->nop();
     } else {
       __ delayed()->ld_ptr(dst, oopDesc::klass_offset_in_bytes(), G4_dst_klass);
     }
     //  if (src->klass() != dst->klass()) return -1;
     __ cmp(G3_src_klass, G4_dst_klass);
     __ brx(Assembler::notEqual, false, Assembler::pn, L_failed);
     __ delayed()->nop();
     //  if (!src->is_Array()) return -1;
     __ cmp(G5_lh, Klass::_lh_neutral_value); // < 0
     __ br(Assembler::greaterEqual, false, Assembler::pn, L_failed);
     // At this point, it is known to be a typeArray (array_tag 0x3).
 #ifdef ASSERT
     __ delayed()->nop();
     { Label L;
       jint lh_prim_tag_in_place = (Klass::_lh_array_tag_type_value << Klass::_lh_array_tag_shift);
       __ set(lh_prim_tag_in_place, O5_temp);
       __ cmp(G5_lh,                O5_temp);
       __ br(Assembler::greaterEqual, false, Assembler::pt, L);
       __ delayed()->nop();
       __ stop("must be a primitive array");
       __ bind(L);
     }
 #else
     __ delayed();                               // match next insn to prev branch
 #endif
     arraycopy_range_checks(src, src_pos, dst, dst_pos, length,
                            O5_temp, G4_dst_klass, L_failed);
     // typeArrayKlass
     //
     // src_addr = (src + array_header_in_bytes()) + (src_pos << log2elemsize);
     // dst_addr = (dst + array_header_in_bytes()) + (dst_pos << log2elemsize);
     //
     const Register G4_offset = G4_dst_klass;    // array offset
     const Register G3_elsize = G3_src_klass;    // log2 element size
     __ srl(G5_lh, Klass::_lh_header_size_shift, G4_offset);
     __ and3(G4_offset, Klass::_lh_header_size_mask, G4_offset); // array_offset
     __ add(src, G4_offset, src);       // src array offset
     __ add(dst, G4_offset, dst);       // dst array offset
     __ and3(G5_lh, Klass::_lh_log2_element_size_mask, G3_elsize); // log2 element size
     // next registers should be set before the jump to corresponding stub
     const Register from     = O0;  // source array address
     const Register to       = O1;  // destination array address
     const Register count    = O2;  // elements count
     // 'from', 'to', 'count' registers should be set in this order
     // since they are the same as 'src', 'src_pos', 'dst'.
     BLOCK_COMMENT("scale indexes to element size");
     __ sll_ptr(src_pos, G3_elsize, src_pos);
     __ sll_ptr(dst_pos, G3_elsize, dst_pos);
     __ add(src, src_pos, from);       // src_addr
     __ add(dst, dst_pos, to);         // dst_addr
     BLOCK_COMMENT("choose copy loop based on element size");
     __ cmp(G3_elsize, 0);
     __ br(Assembler::equal,true,Assembler::pt,StubRoutines::_jbyte_arraycopy);
     __ delayed()->signx(length, count); // length
     __ cmp(G3_elsize, LogBytesPerShort);
     __ br(Assembler::equal,true,Assembler::pt,StubRoutines::_jshort_arraycopy);
     __ delayed()->signx(length, count); // length
     __ cmp(G3_elsize, LogBytesPerInt);
     __ br(Assembler::equal,true,Assembler::pt,StubRoutines::_jint_arraycopy);
     __ delayed()->signx(length, count); // length
 #ifdef ASSERT
     { Label L;
       __ cmp(G3_elsize, LogBytesPerLong);
       __ br(Assembler::equal, false, Assembler::pt, L);
       __ delayed()->nop();
       __ stop("must be long copy, but elsize is wrong");
       __ bind(L);
     }
 #endif
     __ br(Assembler::always,false,Assembler::pt,StubRoutines::_jlong_arraycopy);
     __ delayed()->signx(length, count); // length
     // objArrayKlass
   __ BIND(L_objArray);
     // live at this point:  G3_src_klass, G4_dst_klass, src[_pos], dst[_pos], length
     Label L_plain_copy, L_checkcast_copy;
     //  test array classes for subtyping
     __ cmp(G3_src_klass, G4_dst_klass);         // usual case is exact equality
     __ brx(Assembler::notEqual, true, Assembler::pn, L_checkcast_copy);
     __ delayed()->lduw(G4_dst_klass, lh_offset, O5_temp); // hoisted from below
     // Identically typed arrays can be copied without element-wise checks.
     arraycopy_range_checks(src, src_pos, dst, dst_pos, length,
                            O5_temp, G5_lh, L_failed);
     __ add(src, arrayOopDesc::base_offset_in_bytes(T_OBJECT), src); //src offset
     __ add(dst, arrayOopDesc::base_offset_in_bytes(T_OBJECT), dst); //dst offset
     __ sll_ptr(src_pos, LogBytesPerHeapOop, src_pos);
     __ sll_ptr(dst_pos, LogBytesPerHeapOop, dst_pos);
     __ add(src, src_pos, from);       // src_addr
     __ add(dst, dst_pos, to);         // dst_addr
   __ BIND(L_plain_copy);
     __ br(Assembler::always, false, Assembler::pt,StubRoutines::_oop_arraycopy);
     __ delayed()->signx(length, count); // length
   __ BIND(L_checkcast_copy);
     // live at this point:  G3_src_klass, G4_dst_klass
     {
       // Before looking at dst.length, make sure dst is also an objArray.
       // lduw(G4_dst_klass, lh_offset, O5_temp); // hoisted to delay slot
       __ cmp(G5_lh,                    O5_temp);
       __ br(Assembler::notEqual, false, Assembler::pn, L_failed);
       // It is safe to examine both src.length and dst.length.
       __ delayed();                             // match next insn to prev branch
       arraycopy_range_checks(src, src_pos, dst, dst_pos, length,
                              O5_temp, G5_lh, L_failed);
       // Marshal the base address arguments now, freeing registers.
       __ add(src, arrayOopDesc::base_offset_in_bytes(T_OBJECT), src); //src offset
       __ add(dst, arrayOopDesc::base_offset_in_bytes(T_OBJECT), dst); //dst offset
       __ sll_ptr(src_pos, LogBytesPerHeapOop, src_pos);
       __ sll_ptr(dst_pos, LogBytesPerHeapOop, dst_pos);
       __ add(src, src_pos, from);               // src_addr
       __ add(dst, dst_pos, to);                 // dst_addr
       __ signx(length, count);                  // length (reloaded)
       Register sco_temp = O3;                   // this register is free now
       assert_different_registers(from, to, count, sco_temp,
                                  G4_dst_klass, G3_src_klass);
       // Generate the type check.
       int sco_offset = (klassOopDesc::header_size() * HeapWordSize +
                         Klass::super_check_offset_offset_in_bytes());
       __ lduw(G4_dst_klass, sco_offset, sco_temp);
       generate_type_check(G3_src_klass, sco_temp, G4_dst_klass,
                           O5_temp, L_plain_copy);
       // Fetch destination element klass from the objArrayKlass header.
       int ek_offset = (klassOopDesc::header_size() * HeapWordSize +
                        objArrayKlass::element_klass_offset_in_bytes());
       // the checkcast_copy loop needs two extra arguments:
       __ ld_ptr(G4_dst_klass, ek_offset, O4);   // dest elem klass
       // lduw(O4, sco_offset, O3);              // sco of elem klass
       __ br(Assembler::always, false, Assembler::pt, checkcast_copy_entry);
       __ delayed()->lduw(O4, sco_offset, O3);
     }
   __ BIND(L_failed);
     __ retl();
     __ delayed()->sub(G0, 1, O0); // return -1
     return start;
   }
   void generate_arraycopy_stubs() {
     // Note:  the disjoint stubs must be generated first, some of
     //        the conjoint stubs use them.
     StubRoutines::_jbyte_disjoint_arraycopy  = generate_disjoint_byte_copy(false, "jbyte_disjoint_arraycopy");
     StubRoutines::_jshort_disjoint_arraycopy = generate_disjoint_short_copy(false, "jshort_disjoint_arraycopy");
     StubRoutines::_jint_disjoint_arraycopy   = generate_disjoint_int_copy(false, "jint_disjoint_arraycopy");
     StubRoutines::_jlong_disjoint_arraycopy  = generate_disjoint_long_copy(false, "jlong_disjoint_arraycopy");
     StubRoutines::_oop_disjoint_arraycopy    = generate_disjoint_oop_copy(false, "oop_disjoint_arraycopy");
     StubRoutines::_arrayof_jbyte_disjoint_arraycopy  = generate_disjoint_byte_copy(true, "arrayof_jbyte_disjoint_arraycopy");
     StubRoutines::_arrayof_jshort_disjoint_arraycopy = generate_disjoint_short_copy(true, "arrayof_jshort_disjoint_arraycopy");
     StubRoutines::_arrayof_jint_disjoint_arraycopy   = generate_disjoint_int_copy(true, "arrayof_jint_disjoint_arraycopy");
     StubRoutines::_arrayof_jlong_disjoint_arraycopy  = generate_disjoint_long_copy(true, "arrayof_jlong_disjoint_arraycopy");
     StubRoutines::_arrayof_oop_disjoint_arraycopy    =  generate_disjoint_oop_copy(true, "arrayof_oop_disjoint_arraycopy");
     StubRoutines::_jbyte_arraycopy  = generate_conjoint_byte_copy(false, "jbyte_arraycopy");
     StubRoutines::_jshort_arraycopy = generate_conjoint_short_copy(false, "jshort_arraycopy");
     StubRoutines::_jint_arraycopy   = generate_conjoint_int_copy(false, "jint_arraycopy");
     StubRoutines::_jlong_arraycopy  = generate_conjoint_long_copy(false, "jlong_arraycopy");
     StubRoutines::_oop_arraycopy    = generate_conjoint_oop_copy(false, "oop_arraycopy");
     StubRoutines::_arrayof_jbyte_arraycopy    = generate_conjoint_byte_copy(true, "arrayof_jbyte_arraycopy");
     StubRoutines::_arrayof_jshort_arraycopy   = generate_conjoint_short_copy(true, "arrayof_jshort_arraycopy");
 #ifdef _LP64
     // since sizeof(jint) < sizeof(HeapWord), there's a different flavor:
     StubRoutines::_arrayof_jint_arraycopy     = generate_conjoint_int_copy(true, "arrayof_jint_arraycopy");
   #else
     StubRoutines::_arrayof_jint_arraycopy     = StubRoutines::_jint_arraycopy;
 #endif
     StubRoutines::_arrayof_jlong_arraycopy    = StubRoutines::_jlong_arraycopy;
     StubRoutines::_arrayof_oop_arraycopy      = StubRoutines::_oop_arraycopy;
     StubRoutines::_checkcast_arraycopy = generate_checkcast_copy("checkcast_arraycopy");
     StubRoutines::_unsafe_arraycopy    = generate_unsafe_copy("unsafe_arraycopy");
     StubRoutines::_generic_arraycopy   = generate_generic_copy("generic_arraycopy");
   }
   void generate_initial() {
     // Generates all stubs and initializes the entry points
     //------------------------------------------------------------------------------------------------------------------------
     // entry points that exist in all platforms
     // Note: This is code that could be shared among different platforms - however the benefit seems to be smaller than
     //       the disadvantage of having a much more complicated generator structure. See also comment in stubRoutines.hpp.
     StubRoutines::_forward_exception_entry                 = generate_forward_exception();
     StubRoutines::_call_stub_entry                         = generate_call_stub(StubRoutines::_call_stub_return_address);
     StubRoutines::_catch_exception_entry                   = generate_catch_exception();
     //------------------------------------------------------------------------------------------------------------------------
     // entry points that are platform specific
     StubRoutines::Sparc::_test_stop_entry                  = generate_test_stop();
     StubRoutines::Sparc::_stop_subroutine_entry            = generate_stop_subroutine();
     StubRoutines::Sparc::_flush_callers_register_windows_entry = generate_flush_callers_register_windows();
 #if !defined(COMPILER2) && !defined(_LP64)
     StubRoutines::_atomic_xchg_entry         = generate_atomic_xchg();
     StubRoutines::_atomic_cmpxchg_entry      = generate_atomic_cmpxchg();
     StubRoutines::_atomic_add_entry          = generate_atomic_add();
     StubRoutines::_atomic_xchg_ptr_entry     = StubRoutines::_atomic_xchg_entry;
     StubRoutines::_atomic_cmpxchg_ptr_entry  = StubRoutines::_atomic_cmpxchg_entry;
     StubRoutines::_atomic_cmpxchg_long_entry = generate_atomic_cmpxchg_long();
     StubRoutines::_atomic_add_ptr_entry      = StubRoutines::_atomic_add_entry;
 #endif  // COMPILER2 !=> _LP64
   }
   void generate_all() {
     // Generates all stubs and initializes the entry points
     // Generate partial_subtype_check first here since its code depends on
     // UseZeroBaseCompressedOops which is defined after heap initialization.
     StubRoutines::Sparc::_partial_subtype_check                = generate_partial_subtype_check();
     // These entry points require SharedInfo::stack0 to be set up in non-core builds
     StubRoutines::_throw_AbstractMethodError_entry         = generate_throw_exception("AbstractMethodError throw_exception",          CAST_FROM_FN_PTR(address, SharedRuntime::throw_AbstractMethodError),  false);
     StubRoutines::_throw_IncompatibleClassChangeError_entry= generate_throw_exception("IncompatibleClassChangeError throw_exception", CAST_FROM_FN_PTR(address, SharedRuntime::throw_IncompatibleClassChangeError),  false);
     StubRoutines::_throw_ArithmeticException_entry         = generate_throw_exception("ArithmeticException throw_exception",          CAST_FROM_FN_PTR(address, SharedRuntime::throw_ArithmeticException),  true);
     StubRoutines::_throw_NullPointerException_entry        = generate_throw_exception("NullPointerException throw_exception",         CAST_FROM_FN_PTR(address, SharedRuntime::throw_NullPointerException), true);
     StubRoutines::_throw_NullPointerException_at_call_entry= generate_throw_exception("NullPointerException at call throw_exception", CAST_FROM_FN_PTR(address, SharedRuntime::throw_NullPointerException_at_call), false);
     StubRoutines::_throw_StackOverflowError_entry          = generate_throw_exception("StackOverflowError throw_exception",           CAST_FROM_FN_PTR(address, SharedRuntime::throw_StackOverflowError),   false);
     StubRoutines::_handler_for_unsafe_access_entry =
       generate_handler_for_unsafe_access();
     // support for verify_oop (must happen after universe_init)
     StubRoutines::_verify_oop_subroutine_entry     = generate_verify_oop_subroutine();
     // arraycopy stubs used by compilers
     generate_arraycopy_stubs();
     // generic method handle stubs
     if (EnableMethodHandles && SystemDictionary::MethodHandle_klass() != NULL) {
       for (MethodHandles::EntryKind ek = MethodHandles::_EK_FIRST;
            ek < MethodHandles::_EK_LIMIT;
            ek = MethodHandles::EntryKind(1 + (int)ek)) {
         StubCodeMark mark(this, "MethodHandle", MethodHandles::entry_name(ek));
         MethodHandles::generate_method_handle_stub(_masm, ek);
       }
     }
     // Don't initialize the platform math functions since sparc
     // doesn't have intrinsics for these operations.
   }
  public:
   StubGenerator(CodeBuffer* code, bool all) : StubCodeGenerator(code) {
     // replace the standard masm with a special one:
     _masm = new MacroAssembler(code);
     _stub_count = !all ? 0x100 : 0x200;
     if (all) {
       generate_all();
     } else {
       generate_initial();
     }
     // make sure this stub is available for all local calls
     if (_atomic_add_stub.is_unbound()) {
       // generate a second time, if necessary
       (void) generate_atomic_add();
     }
   }
  private:
   int _stub_count;
   void stub_prolog(StubCodeDesc* cdesc) {
     # ifdef ASSERT
       // put extra information in the stub code, to make it more readable
 #ifdef _LP64
 // Write the high part of the address
 // [RGV] Check if there is a dependency on the size of this prolog
       __ emit_data((intptr_t)cdesc >> 32,    relocInfo::none);
 #endif
       __ emit_data((intptr_t)cdesc,    relocInfo::none);
       __ emit_data(++_stub_count, relocInfo::none);
     # endif
     align(true);
   }
   void align(bool at_header = false) {
     // %%%%% move this constant somewhere else
     // UltraSPARC cache line size is 8 instructions:
     const unsigned int icache_line_size = 32;
     const unsigned int icache_half_line_size = 16;
     if (at_header) {
       while ((intptr_t)(__ pc()) % icache_line_size != 0) {
         __ emit_data(0, relocInfo::none);
       }
     } else {
       while ((intptr_t)(__ pc()) % icache_half_line_size != 0) {
         __ nop();
       }
     }
   }
 }; // end class declaration
 address StubGenerator::disjoint_byte_copy_entry  = NULL;
 address StubGenerator::disjoint_short_copy_entry = NULL;
 address StubGenerator::disjoint_int_copy_entry   = NULL;
 address StubGenerator::disjoint_long_copy_entry  = NULL;
 address StubGenerator::disjoint_oop_copy_entry   = NULL;
 address StubGenerator::byte_copy_entry  = NULL;
 address StubGenerator::short_copy_entry = NULL;
 address StubGenerator::int_copy_entry   = NULL;
 address StubGenerator::long_copy_entry  = NULL;
 address StubGenerator::oop_copy_entry   = NULL;
 address StubGenerator::checkcast_copy_entry = NULL;
 void StubGenerator_generate(CodeBuffer* code, bool all) {
   StubGenerator g(code, all);
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/cpu/sparc/vm/stubGenerator_sparc.cpp@2338d41fbd81 (annotated)

src/cpu/sparc/vm/stubGenerator_sparc.cpp