1 /*
2 * Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved.
3 * Copyright 2012, 2014 SAP AG. 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 "nativeInst_ppc.hpp"
35 #include "opto/runtime.hpp"
36 #include "runtime/interfaceSupport.hpp"
37 #include "runtime/sharedRuntime.hpp"
38 #include "runtime/stubRoutines.hpp"
39 #include "runtime/vframeArray.hpp"
40 #include "utilities/globalDefinitions.hpp"
41 #endif
42
43 #define __ masm->
44
45
46 #ifdef COMPILER2
47
48 // SP adjustment (must use unextended SP) for method handle call sites
49 // during exception handling.
50 static intptr_t adjust_SP_for_methodhandle_callsite(JavaThread *thread) {
51 RegisterMap map(thread, false);
52 // The frame constructor will do the correction for us (see frame::adjust_unextended_SP).
53 frame mh_caller_frame = thread->last_frame().sender(&map);
54 assert(mh_caller_frame.is_compiled_frame(), "Only may reach here for compiled MH call sites");
55 return (intptr_t) mh_caller_frame.unextended_sp();
56 }
57
58 //------------------------------generate_exception_blob---------------------------
59 // Creates exception blob at the end.
60 // Using exception blob, this code is jumped from a compiled method.
61 //
62 // Given an exception pc at a call we call into the runtime for the
63 // handler in this method. This handler might merely restore state
64 // (i.e. callee save registers) unwind the frame and jump to the
65 // exception handler for the nmethod if there is no Java level handler
66 // for the nmethod.
67 //
68 // This code is entered with a jmp.
69 //
70 // Arguments:
71 // R3_ARG1: exception oop
72 // R4_ARG2: exception pc
73 //
74 // Results:
75 // R3_ARG1: exception oop
76 // R4_ARG2: exception pc in caller
77 // destination: exception handler of caller
78 //
79 // Note: the exception pc MUST be at a call (precise debug information)
80 //
81 void OptoRuntime::generate_exception_blob() {
82 // Allocate space for the code.
83 ResourceMark rm;
84 // Setup code generation tools.
85 CodeBuffer buffer("exception_blob", 2048, 1024);
86 InterpreterMacroAssembler* masm = new InterpreterMacroAssembler(&buffer);
87
88 address start = __ pc();
89
90 int frame_size_in_bytes = frame::abi_reg_args_size;
91 OopMap* map = new OopMap(frame_size_in_bytes / sizeof(jint), 0);
92
93 // Exception pc is 'return address' for stack walker.
94 __ std(R4_ARG2/*exception pc*/, _abi(lr), R1_SP);
95
96 // Store the exception in the Thread object.
97 __ std(R3_ARG1/*exception oop*/, in_bytes(JavaThread::exception_oop_offset()), R16_thread);
98 __ std(R4_ARG2/*exception pc*/, in_bytes(JavaThread::exception_pc_offset()), R16_thread);
99
100 // Save callee-saved registers.
101 // Push a C frame for the exception blob. It is needed for the C call later on.
102 __ push_frame_reg_args(0, R11_scratch1);
103
104 // This call does all the hard work. It checks if an exception handler
105 // exists in the method.
106 // If so, it returns the handler address.
107 // If not, it prepares for stack-unwinding, restoring the callee-save
108 // registers of the frame being removed.
109 __ set_last_Java_frame(/*sp=*/R1_SP, noreg);
110
111 __ mr(R3_ARG1, R16_thread);
112 #if defined(ABI_ELFv2)
113 __ call_c((address) OptoRuntime::handle_exception_C, relocInfo::none);
114 #else
115 __ call_c(CAST_FROM_FN_PTR(FunctionDescriptor*, OptoRuntime::handle_exception_C),
116 relocInfo::none);
117 #endif
118 address calls_return_pc = __ last_calls_return_pc();
119 # ifdef ASSERT
120 __ cmpdi(CCR0, R3_RET, 0);
121 __ asm_assert_ne("handle_exception_C must not return NULL", 0x601);
122 # endif
123
124 // Set an oopmap for the call site. This oopmap will only be used if we
125 // are unwinding the stack. Hence, all locations will be dead.
126 // Callee-saved registers will be the same as the frame above (i.e.,
127 // handle_exception_stub), since they were restored when we got the
128 // exception.
129 OopMapSet* oop_maps = new OopMapSet();
130 oop_maps->add_gc_map(calls_return_pc - start, map);
131
132 // Get unextended_sp for method handle call sites.
133 Label mh_callsite, mh_done; // Use a 2nd c call if it's a method handle call site.
134 __ lwa(R4_ARG2, in_bytes(JavaThread::is_method_handle_return_offset()), R16_thread);
135 __ cmpwi(CCR0, R4_ARG2, 0);
136 __ bne(CCR0, mh_callsite);
137
138 __ mtctr(R3_RET); // Move address of exception handler to SR_CTR.
139 __ reset_last_Java_frame();
140 __ pop_frame();
141
142 __ bind(mh_done);
143 // We have a handler in register SR_CTR (could be deopt blob).
144
145 // Get the exception oop.
146 __ ld(R3_ARG1, in_bytes(JavaThread::exception_oop_offset()), R16_thread);
147
148 // Get the exception pc in case we are deoptimized.
149 __ ld(R4_ARG2, in_bytes(JavaThread::exception_pc_offset()), R16_thread);
150
151 // Reset thread values.
152 __ li(R0, 0);
153 #ifdef ASSERT
154 __ std(R0, in_bytes(JavaThread::exception_handler_pc_offset()), R16_thread);
155 __ std(R0, in_bytes(JavaThread::exception_pc_offset()), R16_thread);
156 #endif
157 // Clear the exception oop so GC no longer processes it as a root.
158 __ std(R0, in_bytes(JavaThread::exception_oop_offset()), R16_thread);
159
160 // Move exception pc into SR_LR.
161 __ mtlr(R4_ARG2);
162 __ bctr();
163
164
165 // Same as above, but also set sp to unextended_sp.
166 __ bind(mh_callsite);
167 __ mr(R31, R3_RET); // Save branch address.
168 __ mr(R3_ARG1, R16_thread);
169 #if defined(ABI_ELFv2)
170 __ call_c((address) adjust_SP_for_methodhandle_callsite, relocInfo::none);
171 #else
172 __ call_c(CAST_FROM_FN_PTR(FunctionDescriptor*, adjust_SP_for_methodhandle_callsite), relocInfo::none);
173 #endif
174 // Returns unextended_sp in R3_RET.
175
176 __ mtctr(R31); // Move address of exception handler to SR_CTR.
177 __ reset_last_Java_frame();
178
179 __ mr(R1_SP, R3_RET); // Set sp to unextended_sp.
180 __ b(mh_done);
181
182
183 // Make sure all code is generated.
184 masm->flush();
185
186 // Set exception blob.
187 _exception_blob = ExceptionBlob::create(&buffer, oop_maps,
188 frame_size_in_bytes/wordSize);
189 }
190
191 #endif // COMPILER2