1 /*
2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2016 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/macroAssembler.inline.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "code/vmreg.hpp"
31 #include "interpreter/interpreter.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "nativeInst_s390.hpp"
34 #include "opto/runtime.hpp"
35 #include "runtime/interfaceSupport.hpp"
36 #include "runtime/sharedRuntime.hpp"
37 #include "runtime/stubRoutines.hpp"
38 #include "runtime/vframeArray.hpp"
39 #include "utilities/globalDefinitions.hpp"
40 #include "vmreg_s390.inline.hpp"
41 #endif
42
43 #define __ masm->
44
45
46 //------------------------------generate_exception_blob---------------------------
47 // creates exception blob at the end
48 // Using exception blob, this code is jumped from a compiled method.
49 // (see emit_exception_handler in s390.ad file)
50 //
51 // Given an exception pc at a call we call into the runtime for the
52 // handler in this method. This handler might merely restore state
53 // (i.e. callee save registers), unwind the frame, and jump to the
54 // exception handler for the nmethod if there is no Java level handler
55 // for the nmethod.
56 //
57 // This code is entered with a branch.
58 //
59 // Arguments:
60 // Z_R2(=Z_ARG1): exception oop
61 // Z_R3(=Z_ARG2): exception pc
62 //
63 // Results:
64 // Z_R2: exception oop
65 // Z_R3: exception pc in caller
66 // destination: exception handler of caller
67 //
68 // Note: the exception pc MUST be at a call (precise debug information)
69
70 void OptoRuntime::generate_exception_blob() {
71
72 // Allocate space for the code
73 ResourceMark rm;
74 // Setup code generation tools
75 CodeBuffer buffer("exception_blob", 2048, 1024);
76 MacroAssembler* masm = new MacroAssembler(&buffer);
77
78 Register handle_exception = Z_ARG5;
79
80 __ verify_thread();
81 __ z_stg(Z_ARG1/*exception oop*/, Address(Z_thread, JavaThread::exception_oop_offset()));
82 __ z_stg(Z_ARG2/*issuing pc*/, Address(Z_thread, JavaThread::exception_pc_offset()));
83
84 // Store issuing pc as return pc into
85 // caller's frame. stack-walking needs it. R14 is not valid here,
86 // because this code gets entered with a jump.
87 __ z_stg(Z_ARG2/*issuing pc*/, _z_abi(return_pc), Z_SP);
88
89 // The following call to function OptoRuntime::handle_exception_C
90 // does all the hard work. It checks if an
91 // exception catch exists in the method. If so, it returns the
92 // handler address. If the nmethod has been deoptimized and it had
93 // a handler the handler address is the deopt blob's
94 // unpack_with_exception entry.
95
96 // push a C frame for the exception blob. it is needed for the
97 // C call later on.
98
99 Register saved_sp = Z_R11;
100
101 __ z_lgr(saved_sp, Z_SP);
102
103 // push frame for blob.
104 int frame_size = __ push_frame_abi160(0);
105
106 __ get_PC(Z_R1/*scratch*/);
107 __ set_last_Java_frame(/*sp=*/Z_SP, /*pc=*/Z_R1);
108
109 // This call can lead to deoptimization of the nmethod holding the handler.
110 __ z_lgr(Z_ARG1, Z_thread); // argument of C function
111 __ call_c(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C));
112
113 __ z_lgr(handle_exception, Z_RET);
114 __ reset_last_Java_frame();
115
116 // Pop the exception blob's C frame that has been pushed before.
117 __ z_lgr(Z_SP, saved_sp);
118
119 // [Z_RET]!=NULL was possible in hotspot5 but not in sapjvm6.
120 // C2I adapter extensions are now removed by a resize in the frame manager
121 // (unwind_initial_activation_pending_exception).
122 #ifdef ASSERT
123 __ z_ltgr(handle_exception, handle_exception);
124 __ asm_assert_ne("handler must not be NULL", 0x852);
125 #endif
126
127 // Handle_exception contains the handler address. If the associated frame
128 // has been deoptimized then the handler has been patched to jump to
129 // the deoptimization blob.
130
131 // If the exception handler jumps to the deoptimization blob, the
132 // exception pc will be read from there.
133 __ z_lg(Z_ARG2, Address(Z_thread, JavaThread::exception_pc_offset()));
134
135 __ z_lg(Z_ARG1, Address(Z_thread, JavaThread::exception_oop_offset()));
136
137 // Clear the exception oop so GC no longer processes it as a root.
138 __ clear_mem(Address(Z_thread, JavaThread::exception_oop_offset()),sizeof(intptr_t));
139 #ifdef ASSERT
140 __ clear_mem(Address(Z_thread, JavaThread::exception_handler_pc_offset()), sizeof(intptr_t));
141 __ clear_mem(Address(Z_thread, JavaThread::exception_pc_offset()), sizeof(intptr_t));
142 #endif
143
144 __ z_br(handle_exception);
145
146 // Make sure all code is generated.
147 masm->flush();
148
149 // Set exception blob.
150 OopMapSet *oop_maps = NULL;
151 _exception_blob = ExceptionBlob::create(&buffer, oop_maps, frame_size/wordSize);
152 }