Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright 1998-2006 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/_runtime_sparc.cpp.incl"

 #define __ masm->

 ExceptionBlob      *OptoRuntime::_exception_blob;

 //------------------------------ generate_exception_blob ---------------------------

 // creates exception blob at the end

 // Using exception blob, this code is jumped from a compiled method.

 // (see emit_exception_handler in sparc.ad file)

 //

 // Given an exception pc at a call we call into the runtime for the

 // handler in this method. This handler might merely restore state

 // (i.e. callee save registers) unwind the frame and jump to the

 // exception handler for the nmethod if there is no Java level handler

 // for the nmethod.

 //

 // This code is entered with a jmp.

 //

 // Arguments:

 //   O0: exception oop

 //   O1: exception pc

 //

 // Results:

 //   O0: exception oop

 //   O1: exception pc in caller or ???

 //   destination: exception handler of caller

 //

 // Note: the exception pc MUST be at a call (precise debug information)

 //

 void OptoRuntime::generate_exception_blob() {

   // allocate space for code

   ResourceMark rm;

   int pad = VerifyThread ? 256 : 0;// Extra slop space for more verify code

   // setup code generation tools

   // Measured 8/7/03 at 256 in 32bit debug build (no VerifyThread)

   // Measured 8/7/03 at 528 in 32bit debug build (VerifyThread)

   CodeBuffer buffer("exception_blob", 600+pad, 512);

   MacroAssembler* masm     = new MacroAssembler(&buffer);

   int framesize_in_bytes = __ total_frame_size_in_bytes(0);

   int framesize_in_words = framesize_in_bytes / wordSize;

   int framesize_in_slots = framesize_in_bytes / sizeof(jint);

   Label L;

   int start = __ offset();

   __ verify_thread();

   __ st_ptr(Oexception,  Address(G2_thread, 0, in_bytes(JavaThread::exception_oop_offset())));

   __ st_ptr(Oissuing_pc, Address(G2_thread, 0, in_bytes(JavaThread::exception_pc_offset())));

   // This call does all the hard work. It checks if an exception catch

   // exists in the method.

   // If so, it returns the handler address.

   // If the nmethod has been deoptimized and it had a handler the handler

   // address is the deopt blob unpack_with_exception entry.

   //

   // If no handler exists it prepares for stack-unwinding, restoring the callee-save

   // registers of the frame being removed.

   //

   __ save_frame(0);

   __ mov(G2_thread, O0);

   __ set_last_Java_frame(SP, noreg);

   __ save_thread(L7_thread_cache);

   // This call can block at exit and nmethod can be deoptimized at that

   // point. If the nmethod had a catch point we would jump to the

   // now deoptimized catch point and fall thru the vanilla deopt

   // path and lose the exception

   // Sure would be simpler if this call didn't block!

   __ call(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C), relocInfo::runtime_call_type);

   __ delayed()->mov(L7_thread_cache, O0);

   // Set an oopmap for the call site.  This oopmap will only be used if we

   // are unwinding the stack.  Hence, all locations will be dead.

   // Callee-saved registers will be the same as the frame above (i.e.,

   // handle_exception_stub), since they were restored when we got the

   // exception.

   OopMapSet *oop_maps = new OopMapSet();

   oop_maps->add_gc_map( __ offset()-start, new OopMap(framesize_in_slots, 0));

   __ bind(L);

   __ restore_thread(L7_thread_cache);

   __ reset_last_Java_frame();

   __ mov(O0, G3_scratch);             // Move handler address to temp

   __ restore();

   // G3_scratch contains handler address

   // Since this may be the deopt blob we must set O7 to look like we returned

   // from the original pc that threw the exception

   __ ld_ptr(Address(G2_thread, 0, in_bytes(JavaThread::exception_pc_offset())), O7);

   __ sub(O7, frame::pc_return_offset, O7);

   assert(Assembler::is_simm13(in_bytes(JavaThread::exception_oop_offset())), "exception offset overflows simm13, following ld instruction cannot be in delay slot");

   __ ld_ptr(Address(G2_thread, 0, in_bytes(JavaThread::exception_oop_offset())), Oexception); // O0

 #ifdef ASSERT

   __ st_ptr(G0, Address(G2_thread, 0, in_bytes(JavaThread::exception_handler_pc_offset())));

   __ st_ptr(G0, Address(G2_thread, 0, in_bytes(JavaThread::exception_pc_offset())));

 #endif

   __ JMP(G3_scratch, 0);

   // Clear the exception oop so GC no longer processes it as a root.

   __ delayed()->st_ptr(G0, Address(G2_thread, 0, in_bytes(JavaThread::exception_oop_offset())));

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

   // make sure all code is generated

   masm->flush();

   _exception_blob = ExceptionBlob::create(&buffer, oop_maps, framesize_in_words);

 }