1 /*
2 * Copyright (c) 1997, 2017, 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 #ifndef SHARE_VM_RUNTIME_JAVACALLS_HPP
26 #define SHARE_VM_RUNTIME_JAVACALLS_HPP
27
28 #include "memory/allocation.hpp"
29 #include "oops/method.hpp"
30 #include "runtime/handles.hpp"
31 #include "runtime/javaFrameAnchor.hpp"
32 #include "runtime/thread.inline.hpp"
33 #include "runtime/vmThread.hpp"
34 #ifdef TARGET_ARCH_x86
35 # include "jniTypes_x86.hpp"
36 #endif
37 #ifdef TARGET_ARCH_aarch64
38 # include "jniTypes_aarch64.hpp"
39 #endif
40 #ifdef TARGET_ARCH_sparc
41 # include "jniTypes_sparc.hpp"
42 #endif
43 #ifdef TARGET_ARCH_zero
44 # include "jniTypes_zero.hpp"
45 #endif
46 #ifdef TARGET_ARCH_arm
47 # include "jniTypes_arm.hpp"
48 #endif
49 #ifdef TARGET_ARCH_ppc
50 # include "jniTypes_ppc.hpp"
51 #endif
52
53 // A JavaCallWrapper is constructed before each JavaCall and destructed after the call.
54 // Its purpose is to allocate/deallocate a new handle block and to save/restore the last
55 // Java fp/sp. A pointer to the JavaCallWrapper is stored on the stack.
56
57 class JavaCallWrapper: StackObj {
58 friend class VMStructs;
59 private:
60 JavaThread* _thread; // the thread to which this call belongs
61 JNIHandleBlock* _handles; // the saved handle block
62 Method* _callee_method; // to be able to collect arguments if entry frame is top frame
63 oop _receiver; // the receiver of the call (if a non-static call)
64
65 JavaFrameAnchor _anchor; // last thread anchor state that we must restore
66
67 JavaValue* _result; // result value
68
69 public:
70 // Construction/destruction
71 JavaCallWrapper(methodHandle callee_method, Handle receiver, JavaValue* result, TRAPS);
72 ~JavaCallWrapper();
73
74 // Accessors
75 JavaThread* thread() const { return _thread; }
76 JNIHandleBlock* handles() const { return _handles; }
77
78 JavaFrameAnchor* anchor(void) { return &_anchor; }
79
80 JavaValue* result() const { return _result; }
81 // GC support
82 Method* callee_method() { return _callee_method; }
83 oop receiver() { return _receiver; }
84 void oops_do(OopClosure* f);
85
86 bool is_first_frame() const { return _anchor.last_Java_sp() == NULL; }
87
88 };
89
90
91 // Encapsulates arguments to a JavaCall (faster, safer, and more convenient than using var-args)
92 class JavaCallArguments : public StackObj {
93 private:
94 enum Constants {
95 _default_size = 8 // Must be at least # of arguments in JavaCalls methods
96 };
97
98 intptr_t _value_buffer [_default_size + 1];
99 u_char _value_state_buffer[_default_size + 1];
100
101 intptr_t* _value;
102 u_char* _value_state;
103 int _size;
104 int _max_size;
105 bool _start_at_zero; // Support late setting of receiver
106
107 void initialize() {
108 // Starts at first element to support set_receiver.
109 _value = &_value_buffer[1];
110 _value_state = &_value_state_buffer[1];
111
112 _max_size = _default_size;
113 _size = 0;
114 _start_at_zero = false;
115 }
116
117 // Helper for push_oop and the like. The value argument is a
118 // "handle" that refers to an oop. We record the address of the
119 // handle rather than the designated oop. The handle is later
120 // resolved to the oop by parameters(). This delays the exposure of
121 // naked oops until it is GC-safe.
122 template<typename T>
123 inline int push_oop_impl(T handle, int size) {
124 // JNITypes::put_obj expects an oop value, so we play fast and
125 // loose with the type system. The cast from handle type to oop
126 // *must* use a C-style cast. In a product build it performs a
127 // reinterpret_cast. In a debug build (more accurately, in a
128 // CHECK_UNHANDLED_OOPS build) it performs a static_cast, invoking
129 // the debug-only oop class's conversion from void* constructor.
130 JNITypes::put_obj((oop)handle, _value, size); // Updates size.
131 return size; // Return the updated size.
132 }
133
134 public:
135 JavaCallArguments() { initialize(); }
136
137 JavaCallArguments(Handle receiver) {
138 initialize();
139 push_oop(receiver);
140 }
141
142 JavaCallArguments(int max_size) {
143 if (max_size > _default_size) {
144 _value = NEW_RESOURCE_ARRAY(intptr_t, max_size + 1);
145 _value_state = NEW_RESOURCE_ARRAY(u_char, max_size + 1);
146
147 // Reserve room for potential receiver in value and state
148 _value++;
149 _value_state++;
150
151 _max_size = max_size;
152 _size = 0;
153 _start_at_zero = false;
154 } else {
155 initialize();
156 }
157 }
158
159 // The possible values for _value_state elements.
160 enum {
161 value_state_primitive,
162 value_state_oop,
163 value_state_handle,
164 value_state_jobject,
165 value_state_limit
166 };
167
168 inline void push_oop(Handle h) {
169 _value_state[_size] = value_state_handle;
170 _size = push_oop_impl(h.raw_value(), _size);
171 }
172
173 inline void push_jobject(jobject h) {
174 _value_state[_size] = value_state_jobject;
175 _size = push_oop_impl(h, _size);
176 }
177
178 inline void push_int(int i) {
179 _value_state[_size] = value_state_primitive;
180 JNITypes::put_int(i, _value, _size);
181 }
182
183 inline void push_double(double d) {
184 _value_state[_size] = value_state_primitive;
185 _value_state[_size + 1] = value_state_primitive;
186 JNITypes::put_double(d, _value, _size);
187 }
188
189 inline void push_long(jlong l) {
190 _value_state[_size] = value_state_primitive;
191 _value_state[_size + 1] = value_state_primitive;
192 JNITypes::put_long(l, _value, _size);
193 }
194
195 inline void push_float(float f) {
196 _value_state[_size] = value_state_primitive;
197 JNITypes::put_float(f, _value, _size);
198 }
199
200 // receiver
201 Handle receiver() {
202 assert(_size > 0, "must at least be one argument");
203 assert(_value_state[0] == value_state_handle,
204 "first argument must be an oop");
205 assert(_value[0] != 0, "receiver must be not-null");
206 return Handle((oop*)_value[0], false);
207 }
208
209 void set_receiver(Handle h) {
210 assert(_start_at_zero == false, "can only be called once");
211 _start_at_zero = true;
212 _value_state--;
213 _value--;
214 _size++;
215 _value_state[0] = value_state_handle;
216 push_oop_impl(h.raw_value(), 0);
217 }
218
219 // Converts all Handles to oops, and returns a reference to parameter vector
220 intptr_t* parameters() ;
221 int size_of_parameters() const { return _size; }
222
223 // Verify that pushed arguments fits a given method
224 void verify(methodHandle method, BasicType return_type);
225 };
226
227 // All calls to Java have to go via JavaCalls. Sets up the stack frame
228 // and makes sure that the last_Java_frame pointers are chained correctly.
229 //
230
231 class JavaCalls: AllStatic {
232 static void call_helper(JavaValue* result, methodHandle* method, JavaCallArguments* args, TRAPS);
233 public:
234 // Optimized Constuctor call
235 static void call_default_constructor(JavaThread* thread, methodHandle method, Handle receiver, TRAPS);
236
237 // call_special
238 // ------------
239 // The receiver must be first oop in argument list
240 static void call_special(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS);
241
242 static void call_special(JavaValue* result, Handle receiver, KlassHandle klass, Symbol* name, Symbol* signature, TRAPS); // No args
243 static void call_special(JavaValue* result, Handle receiver, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS);
244 static void call_special(JavaValue* result, Handle receiver, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS);
245
246 // virtual call
247 // ------------
248
249 // The receiver must be first oop in argument list
250 static void call_virtual(JavaValue* result, KlassHandle spec_klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS);
251
252 static void call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, Symbol* name, Symbol* signature, TRAPS); // No args
253 static void call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS);
254 static void call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS);
255
256 // Static call
257 // -----------
258 static void call_static(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS);
259
260 static void call_static(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, TRAPS);
261 static void call_static(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS);
262 static void call_static(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS);
263
264 // Low-level interface
265 static void call(JavaValue* result, methodHandle method, JavaCallArguments* args, TRAPS);
266 };
267
268 #endif // SHARE_VM_RUNTIME_JAVACALLS_HPP