duke@435: /*
jrose@1934:  * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: #include "incls/_precompiled.incl"
duke@435: #include "incls/_runtime_sparc.cpp.incl"
duke@435: 
duke@435: 
duke@435: #define __ masm->
duke@435: 
duke@435: ExceptionBlob      *OptoRuntime::_exception_blob;
duke@435: 
duke@435: //------------------------------ generate_exception_blob ---------------------------
duke@435: // creates exception blob at the end
duke@435: // Using exception blob, this code is jumped from a compiled method.
duke@435: // (see emit_exception_handler in sparc.ad file)
duke@435: //
duke@435: // Given an exception pc at a call we call into the runtime for the
duke@435: // handler in this method. This handler might merely restore state
duke@435: // (i.e. callee save registers) unwind the frame and jump to the
duke@435: // exception handler for the nmethod if there is no Java level handler
duke@435: // for the nmethod.
duke@435: //
duke@435: // This code is entered with a jmp.
duke@435: //
duke@435: // Arguments:
duke@435: //   O0: exception oop
duke@435: //   O1: exception pc
duke@435: //
duke@435: // Results:
duke@435: //   O0: exception oop
duke@435: //   O1: exception pc in caller or ???
duke@435: //   destination: exception handler of caller
duke@435: //
duke@435: // Note: the exception pc MUST be at a call (precise debug information)
duke@435: //
duke@435: void OptoRuntime::generate_exception_blob() {
duke@435:   // allocate space for code
duke@435:   ResourceMark rm;
duke@435:   int pad = VerifyThread ? 256 : 0;// Extra slop space for more verify code
duke@435: 
duke@435:   // setup code generation tools
duke@435:   // Measured 8/7/03 at 256 in 32bit debug build (no VerifyThread)
duke@435:   // Measured 8/7/03 at 528 in 32bit debug build (VerifyThread)
duke@435:   CodeBuffer buffer("exception_blob", 600+pad, 512);
duke@435:   MacroAssembler* masm     = new MacroAssembler(&buffer);
duke@435: 
duke@435:   int framesize_in_bytes = __ total_frame_size_in_bytes(0);
duke@435:   int framesize_in_words = framesize_in_bytes / wordSize;
duke@435:   int framesize_in_slots = framesize_in_bytes / sizeof(jint);
duke@435: 
duke@435:   Label L;
duke@435: 
duke@435:   int start = __ offset();
duke@435: 
duke@435:   __ verify_thread();
twisti@1162:   __ st_ptr(Oexception,  G2_thread, JavaThread::exception_oop_offset());
twisti@1162:   __ st_ptr(Oissuing_pc, G2_thread, JavaThread::exception_pc_offset());
duke@435: 
duke@435:   // This call does all the hard work. It checks if an exception catch
duke@435:   // exists in the method.
duke@435:   // If so, it returns the handler address.
duke@435:   // If the nmethod has been deoptimized and it had a handler the handler
duke@435:   // address is the deopt blob unpack_with_exception entry.
duke@435:   //
duke@435:   // If no handler exists it prepares for stack-unwinding, restoring the callee-save
duke@435:   // registers of the frame being removed.
duke@435:   //
duke@435:   __ save_frame(0);
duke@435: 
duke@435:   __ mov(G2_thread, O0);
duke@435:   __ set_last_Java_frame(SP, noreg);
duke@435:   __ save_thread(L7_thread_cache);
duke@435: 
duke@435:   // This call can block at exit and nmethod can be deoptimized at that
duke@435:   // point. If the nmethod had a catch point we would jump to the
duke@435:   // now deoptimized catch point and fall thru the vanilla deopt
duke@435:   // path and lose the exception
duke@435:   // Sure would be simpler if this call didn't block!
duke@435:   __ call(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C), relocInfo::runtime_call_type);
duke@435:   __ delayed()->mov(L7_thread_cache, O0);
duke@435: 
duke@435:   // Set an oopmap for the call site.  This oopmap will only be used if we
duke@435:   // are unwinding the stack.  Hence, all locations will be dead.
duke@435:   // Callee-saved registers will be the same as the frame above (i.e.,
duke@435:   // handle_exception_stub), since they were restored when we got the
duke@435:   // exception.
duke@435: 
duke@435:   OopMapSet *oop_maps = new OopMapSet();
duke@435:   oop_maps->add_gc_map( __ offset()-start, new OopMap(framesize_in_slots, 0));
duke@435: 
duke@435:   __ bind(L);
duke@435:   __ restore_thread(L7_thread_cache);
duke@435:   __ reset_last_Java_frame();
duke@435: 
duke@435:   __ mov(O0, G3_scratch);             // Move handler address to temp
duke@435:   __ restore();
duke@435: 
twisti@1922:   // Restore SP from L7 if the exception PC is a MethodHandle call site.
twisti@1922:   __ lduw(Address(G2_thread, JavaThread::is_method_handle_return_offset()), O7);
twisti@1922:   __ tst(O7);
twisti@1922:   __ movcc(Assembler::notZero, false, Assembler::icc, L7_mh_SP_save, SP);
twisti@1922: 
duke@435:   // G3_scratch contains handler address
duke@435:   // Since this may be the deopt blob we must set O7 to look like we returned
duke@435:   // from the original pc that threw the exception
duke@435: 
twisti@1162:   __ ld_ptr(G2_thread, JavaThread::exception_pc_offset(), O7);
duke@435:   __ sub(O7, frame::pc_return_offset, O7);
duke@435: 
duke@435: 
duke@435:   assert(Assembler::is_simm13(in_bytes(JavaThread::exception_oop_offset())), "exception offset overflows simm13, following ld instruction cannot be in delay slot");
twisti@1162:   __ ld_ptr(G2_thread, JavaThread::exception_oop_offset(), Oexception); // O0
duke@435: #ifdef ASSERT
twisti@1162:   __ st_ptr(G0, G2_thread, JavaThread::exception_handler_pc_offset());
twisti@1162:   __ st_ptr(G0, G2_thread, JavaThread::exception_pc_offset());
duke@435: #endif
duke@435:   __ JMP(G3_scratch, 0);
duke@435:   // Clear the exception oop so GC no longer processes it as a root.
twisti@1162:   __ delayed()->st_ptr(G0, G2_thread, JavaThread::exception_oop_offset());
duke@435: 
duke@435:   // -------------
duke@435:   // make sure all code is generated
duke@435:   masm->flush();
duke@435: 
duke@435:   _exception_blob = ExceptionBlob::create(&buffer, oop_maps, framesize_in_words);
duke@435: }