1/*
2 * Copyright (c) 1998, 2016, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2012, 2015 SAP SE. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26#include "precompiled.hpp"
27#ifdef COMPILER2
28#include "asm/assembler.inline.hpp"
29#include "asm/macroAssembler.inline.hpp"
30#include "classfile/systemDictionary.hpp"
31#include "code/vmreg.hpp"
32#include "interpreter/interpreter.hpp"
33#include "interpreter/interp_masm.hpp"
34#include "memory/resourceArea.hpp"
35#include "nativeInst_ppc.hpp"
36#include "opto/runtime.hpp"
37#include "runtime/interfaceSupport.hpp"
38#include "runtime/sharedRuntime.hpp"
39#include "runtime/stubRoutines.hpp"
40#include "runtime/vframeArray.hpp"
41#include "utilities/globalDefinitions.hpp"
42#endif
43
44#define __ masm->
45
46
47#ifdef COMPILER2
48
49//------------------------------generate_exception_blob---------------------------
50// Creates exception blob at the end.
51// Using exception blob, this code is jumped from a compiled method.
52//
53// Given an exception pc at a call we call into the runtime for the
54// handler in this method. This handler might merely restore state
55// (i.e. callee save registers) unwind the frame and jump to the
56// exception handler for the nmethod if there is no Java level handler
57// for the nmethod.
58//
59// This code is entered with a jmp.
60//
61// Arguments:
62//   R3_ARG1: exception oop
63//   R4_ARG2: exception pc
64//
65// Results:
66//   R3_ARG1: exception oop
67//   R4_ARG2: exception pc in caller
68//   destination: exception handler of caller
69//
70// Note: the exception pc MUST be at a call (precise debug information)
71//
72void OptoRuntime::generate_exception_blob() {
73  // Allocate space for the code.
74  ResourceMark rm;
75  // Setup code generation tools.
76  CodeBuffer buffer("exception_blob", 2048, 1024);
77  InterpreterMacroAssembler* masm = new InterpreterMacroAssembler(&buffer);
78
79  address start = __ pc();
80
81  int frame_size_in_bytes = frame::abi_reg_args_size;
82  OopMap* map = new OopMap(frame_size_in_bytes / sizeof(jint), 0);
83
84  // Exception pc is 'return address' for stack walker.
85  __ std(R4_ARG2/*exception pc*/, _abi(lr), R1_SP);
86
87  // Store the exception in the Thread object.
88  __ std(R3_ARG1/*exception oop*/, in_bytes(JavaThread::exception_oop_offset()), R16_thread);
89  __ std(R4_ARG2/*exception pc*/,  in_bytes(JavaThread::exception_pc_offset()),  R16_thread);
90
91  // Save callee-saved registers.
92  // Push a C frame for the exception blob. It is needed for the C call later on.
93  __ push_frame_reg_args(0, R11_scratch1);
94
95  // This call does all the hard work. It checks if an exception handler
96  // exists in the method.
97  // If so, it returns the handler address.
98  // If not, it prepares for stack-unwinding, restoring the callee-save
99  // registers of the frame being removed.
100  __ set_last_Java_frame(/*sp=*/R1_SP, noreg);
101
102  __ mr(R3_ARG1, R16_thread);
103#if defined(ABI_ELFv2)
104  __ call_c((address) OptoRuntime::handle_exception_C, relocInfo::none);
105#else
106  __ call_c(CAST_FROM_FN_PTR(FunctionDescriptor*, OptoRuntime::handle_exception_C),
107            relocInfo::none);
108#endif
109  address calls_return_pc = __ last_calls_return_pc();
110# ifdef ASSERT
111  __ cmpdi(CCR0, R3_RET, 0);
112  __ asm_assert_ne("handle_exception_C must not return NULL", 0x601);
113# endif
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  OopMapSet* oop_maps = new OopMapSet();
121  oop_maps->add_gc_map(calls_return_pc - start, map);
122
123  __ mtctr(R3_RET); // Move address of exception handler to SR_CTR.
124  __ reset_last_Java_frame();
125  __ pop_frame();
126
127  // We have a handler in register SR_CTR (could be deopt blob).
128
129  // Get the exception oop.
130  __ ld(R3_ARG1, in_bytes(JavaThread::exception_oop_offset()), R16_thread);
131
132  // Get the exception pc in case we are deoptimized.
133  __ ld(R4_ARG2, in_bytes(JavaThread::exception_pc_offset()), R16_thread);
134
135  // Reset thread values.
136  __ li(R0, 0);
137#ifdef ASSERT
138  __ std(R0, in_bytes(JavaThread::exception_handler_pc_offset()), R16_thread);
139  __ std(R0, in_bytes(JavaThread::exception_pc_offset()), R16_thread);
140#endif
141  // Clear the exception oop so GC no longer processes it as a root.
142  __ std(R0, in_bytes(JavaThread::exception_oop_offset()), R16_thread);
143
144  // Move exception pc into SR_LR.
145  __ mtlr(R4_ARG2);
146  __ bctr();
147
148  // Make sure all code is generated.
149  masm->flush();
150
151  // Set exception blob.
152  _exception_blob = ExceptionBlob::create(&buffer, oop_maps,
153                                          frame_size_in_bytes/wordSize);
154}
155
156#endif // COMPILER2
157