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