1/*
2 * Copyright (c) 1998, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#include "precompiled.hpp"
26#ifdef COMPILER2
27#include "asm/macroAssembler.inline.hpp"
28#include "classfile/systemDictionary.hpp"
29#include "code/vmreg.hpp"
30#include "interpreter/interpreter.hpp"
31#include "memory/resourceArea.hpp"
32#include "nativeInst_sparc.hpp"
33#include "opto/runtime.hpp"
34#include "runtime/interfaceSupport.hpp"
35#include "runtime/sharedRuntime.hpp"
36#include "runtime/stubRoutines.hpp"
37#include "runtime/vframeArray.hpp"
38#include "utilities/globalDefinitions.hpp"
39#include "vmreg_sparc.inline.hpp"
40#endif
41
42
43#define __ masm->
44
45//------------------------------ generate_exception_blob ---------------------------
46// creates exception blob at the end
47// Using exception blob, this code is jumped from a compiled method.
48// (see emit_exception_handler in sparc.ad file)
49//
50// Given an exception pc at a call we call into the runtime for the
51// handler in this method. This handler might merely restore state
52// (i.e. callee save registers) unwind the frame and jump to the
53// exception handler for the nmethod if there is no Java level handler
54// for the nmethod.
55//
56// This code is entered with a jmp.
57//
58// Arguments:
59//   O0: exception oop
60//   O1: exception pc
61//
62// Results:
63//   O0: exception oop
64//   O1: exception pc in caller or ???
65//   destination: exception handler of caller
66//
67// Note: the exception pc MUST be at a call (precise debug information)
68//
69void OptoRuntime::generate_exception_blob() {
70  // allocate space for code
71  ResourceMark rm;
72  int pad = VerifyThread ? 256 : 0;// Extra slop space for more verify code
73
74  // setup code generation tools
75  // Measured 8/7/03 at 256 in 32bit debug build (no VerifyThread)
76  // Measured 8/7/03 at 528 in 32bit debug build (VerifyThread)
77  CodeBuffer buffer("exception_blob", 600+pad, 512);
78  MacroAssembler* masm     = new MacroAssembler(&buffer);
79
80  int framesize_in_bytes = __ total_frame_size_in_bytes(0);
81  int framesize_in_words = framesize_in_bytes / wordSize;
82  int framesize_in_slots = framesize_in_bytes / sizeof(jint);
83
84  Label L;
85
86  int start = __ offset();
87
88  __ verify_thread();
89  __ st_ptr(Oexception,  G2_thread, JavaThread::exception_oop_offset());
90  __ st_ptr(Oissuing_pc, G2_thread, JavaThread::exception_pc_offset());
91
92  // This call does all the hard work. It checks if an exception catch
93  // exists in the method.
94  // If so, it returns the handler address.
95  // If the nmethod has been deoptimized and it had a handler the handler
96  // address is the deopt blob unpack_with_exception entry.
97  //
98  // If no handler exists it prepares for stack-unwinding, restoring the callee-save
99  // registers of the frame being removed.
100  //
101  __ save_frame(0);
102
103  __ mov(G2_thread, O0);
104  __ set_last_Java_frame(SP, noreg);
105  __ save_thread(L7_thread_cache);
106
107  // This call can block at exit and nmethod can be deoptimized at that
108  // point. If the nmethod had a catch point we would jump to the
109  // now deoptimized catch point and fall thru the vanilla deopt
110  // path and lose the exception
111  // Sure would be simpler if this call didn't block!
112  __ call(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C), relocInfo::runtime_call_type);
113  __ delayed()->mov(L7_thread_cache, O0);
114
115  // Set an oopmap for the call site.  This oopmap will only be used if we
116  // are unwinding the stack.  Hence, all locations will be dead.
117  // Callee-saved registers will be the same as the frame above (i.e.,
118  // handle_exception_stub), since they were restored when we got the
119  // exception.
120
121  OopMapSet *oop_maps = new OopMapSet();
122  oop_maps->add_gc_map( __ offset()-start, new OopMap(framesize_in_slots, 0));
123
124  __ bind(L);
125  __ restore_thread(L7_thread_cache);
126  __ reset_last_Java_frame();
127
128  __ mov(O0, G3_scratch);             // Move handler address to temp
129  __ restore();
130
131  // Restore SP from L7 if the exception PC is a MethodHandle call site.
132  __ lduw(Address(G2_thread, JavaThread::is_method_handle_return_offset()), O7);
133  __ tst(O7);
134  __ movcc(Assembler::notZero, false, Assembler::icc, L7_mh_SP_save, SP);
135
136  // G3_scratch contains handler address
137  // Since this may be the deopt blob we must set O7 to look like we returned
138  // from the original pc that threw the exception
139
140  __ ld_ptr(G2_thread, JavaThread::exception_pc_offset(), O7);
141  __ sub(O7, frame::pc_return_offset, O7);
142
143
144  assert(Assembler::is_simm13(in_bytes(JavaThread::exception_oop_offset())), "exception offset overflows simm13, following ld instruction cannot be in delay slot");
145  __ ld_ptr(G2_thread, JavaThread::exception_oop_offset(), Oexception); // O0
146#ifdef ASSERT
147  __ st_ptr(G0, G2_thread, JavaThread::exception_handler_pc_offset());
148  __ st_ptr(G0, G2_thread, JavaThread::exception_pc_offset());
149#endif
150  __ JMP(G3_scratch, 0);
151  // Clear the exception oop so GC no longer processes it as a root.
152  __ delayed()->st_ptr(G0, G2_thread, JavaThread::exception_oop_offset());
153
154  // -------------
155  // make sure all code is generated
156  masm->flush();
157
158  _exception_blob = ExceptionBlob::create(&buffer, oop_maps, framesize_in_words);
159}
160