1 /*
2 * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved.
3 * Copyright 2009, 2010 Red Hat, Inc.
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 #include "shark/llvmHeaders.hpp"
28 #include "shark/sharkNativeWrapper.hpp"
29 #include "shark/sharkType.hpp"
30
31 using namespace llvm;
32
33 void SharkNativeWrapper::initialize(const char *name) {
34 // Create the function
35 _function = Function::Create(
36 SharkType::entry_point_type(),
37 GlobalVariable::InternalLinkage,
38 name);
39
40 // Get our arguments
41 Function::arg_iterator ai = function()->arg_begin();
42 Argument *method = ai++;
43 method->setName("method");
44 Argument *base_pc = ai++;
45 base_pc->setName("base_pc");
46 code_buffer()->set_base_pc(base_pc);
47 Argument *thread = ai++;
48 thread->setName("thread");
49 set_thread(thread);
50
51 // Create and push our stack frame
52 builder()->SetInsertPoint(CreateBlock());
53 _stack = SharkStack::CreateBuildAndPushFrame(this, method);
54 NOT_PRODUCT(method = NULL);
55
56 // Create the oopmap. We use the one oopmap for every call site in
57 // the wrapper, which results in the odd mild inefficiency but is a
58 // damn sight easier to code.
59 OopMap *oopmap = new OopMap(
60 SharkStack::oopmap_slot_munge(stack()->oopmap_frame_size()),
61 SharkStack::oopmap_slot_munge(arg_size()));
62
63 // Set up the oop_tmp slot if required:
64 // - For static methods we use it to handlize the class argument
65 // for the call, and to protect the same during slow path locks
66 // (if synchronized).
67 // - For methods returning oops, we use it to protect the return
68 // value across safepoints or slow path unlocking.
69 if (is_static() || is_returning_oop()) {
70 _oop_tmp_slot = stack()->slot_addr(
71 stack()->oop_tmp_slot_offset(),
72 SharkType::oop_type(),
73 "oop_tmp_slot");
74
75 oopmap->set_oop(SharkStack::slot2reg(stack()->oop_tmp_slot_offset()));
76 }
77
78 // Set up the monitor slot, for synchronized methods
79 if (is_synchronized()) {
80 Unimplemented();
81 _lock_slot_offset = 23;
82 }
83
84 // Start building the argument list
85 std::vector<Type*> param_types;
86 std::vector<Value*> param_values;
87 PointerType *box_type = PointerType::getUnqual(SharkType::oop_type());
88
89 // First argument is the JNIEnv
90 param_types.push_back(SharkType::jniEnv_type());
91 param_values.push_back(
92 builder()->CreateAddressOfStructEntry(
93 thread,
94 JavaThread::jni_environment_offset(),
95 SharkType::jniEnv_type(),
96 "jni_environment"));
97
98 // For static methods, the second argument is the class
99 if (is_static()) {
100 builder()->CreateStore(
101 builder()->CreateInlineOop(
102 JNIHandles::make_local(
103 target()->method_holder()->java_mirror())),
104 oop_tmp_slot());
105
106 param_types.push_back(box_type);
107 param_values.push_back(oop_tmp_slot());
108
109 _receiver_slot_offset = stack()->oop_tmp_slot_offset();
110 }
111 else if (is_returning_oop()) {
112 // The oop_tmp slot is registered in the oopmap,
113 // so we need to clear it. This is one of the
114 // mild inefficiencies I mentioned earlier.
115 builder()->CreateStore(LLVMValue::null(), oop_tmp_slot());
116 }
117
118 // Parse the arguments
119 for (int i = 0; i < arg_size(); i++) {
120 int slot_offset = stack()->locals_slots_offset() + arg_size() - 1 - i;
121 int adjusted_offset = slot_offset;
122 BasicBlock *null, *not_null, *merge;
123 Value *box;
124 PHINode *phi;
125
126 switch (arg_type(i)) {
127 case T_VOID:
128 break;
129
130 case T_OBJECT:
131 case T_ARRAY:
132 null = CreateBlock("null");
133 not_null = CreateBlock("not_null");
134 merge = CreateBlock("merge");
135
136 box = stack()->slot_addr(slot_offset, SharkType::oop_type());
137 builder()->CreateCondBr(
138 builder()->CreateICmp(
139 ICmpInst::ICMP_EQ,
140 builder()->CreateLoad(box),
141 LLVMValue::null()),
142 null, not_null);
143
144 builder()->SetInsertPoint(null);
145 builder()->CreateBr(merge);
146
147 builder()->SetInsertPoint(not_null);
148 builder()->CreateBr(merge);
149
150 builder()->SetInsertPoint(merge);
151 phi = builder()->CreatePHI(box_type, 0, "boxed_object");
152 phi->addIncoming(ConstantPointerNull::get(box_type), null);
153 phi->addIncoming(box, not_null);
154 box = phi;
155
156 param_types.push_back(box_type);
157 param_values.push_back(box);
158
159 oopmap->set_oop(SharkStack::slot2reg(slot_offset));
160
161 if (i == 0 && !is_static())
162 _receiver_slot_offset = slot_offset;
163
164 break;
165
166 case T_LONG:
167 case T_DOUBLE:
168 adjusted_offset--;
169 // fall through
170
171 default:
172 Type *param_type = SharkType::to_stackType(arg_type(i));
173
174 param_types.push_back(param_type);
175 param_values.push_back(
176 builder()->CreateLoad(stack()->slot_addr(adjusted_offset, param_type)));
177 }
178 }
179
180 // The oopmap is now complete, and everything is written
181 // into the frame except the PC.
182 int pc_offset = code_buffer()->create_unique_offset();
183
184 _oop_maps = new OopMapSet();
185 oop_maps()->add_gc_map(pc_offset, oopmap);
186
187 builder()->CreateStore(
188 builder()->code_buffer_address(pc_offset),
189 stack()->slot_addr(stack()->pc_slot_offset()));
190
191 // Set up the Java frame anchor
192 stack()->CreateSetLastJavaFrame();
193
194 // Lock if necessary
195 if (is_synchronized())
196 Unimplemented();
197
198 // Change the thread state to _thread_in_native
199 CreateSetThreadState(_thread_in_native);
200
201 // Make the call
202 BasicType result_type = target()->result_type();
203 Type* return_type;
204 if (result_type == T_VOID)
205 return_type = SharkType::void_type();
206 else if (is_returning_oop())
207 return_type = box_type;
208 else
209 return_type = SharkType::to_arrayType(result_type);
210 Value* native_function = builder()->CreateIntToPtr(
211 LLVMValue::intptr_constant((intptr_t) target()->native_function()),
212 PointerType::getUnqual(
213 FunctionType::get(return_type, param_types, false)));
214 Value *result = builder()->CreateCall(
215 native_function, llvm::makeArrayRef(param_values));
216
217 // Start the transition back to _thread_in_Java
218 CreateSetThreadState(_thread_in_native_trans);
219
220 // Make sure new state is visible in the GC thread
221 if (os::is_MP()) {
222 if (UseMembar)
223 builder()->CreateFence(llvm::SequentiallyConsistent, llvm::CrossThread);
224 else
225 CreateWriteMemorySerializePage();
226 }
227
228 // Handle safepoint operations, pending suspend requests,
229 // and pending asynchronous exceptions.
230 BasicBlock *check_thread = CreateBlock("check_thread");
231 BasicBlock *do_safepoint = CreateBlock("do_safepoint");
232 BasicBlock *safepointed = CreateBlock("safepointed");
233
234 Value *global_state = builder()->CreateLoad(
235 builder()->CreateIntToPtr(
236 LLVMValue::intptr_constant(
237 (intptr_t) SafepointSynchronize::address_of_state()),
238 PointerType::getUnqual(SharkType::jint_type())),
239 "global_state");
240
241 builder()->CreateCondBr(
242 builder()->CreateICmpNE(
243 global_state,
244 LLVMValue::jint_constant(SafepointSynchronize::_not_synchronized)),
245 do_safepoint, check_thread);
246
247 builder()->SetInsertPoint(check_thread);
248 Value *thread_state = builder()->CreateValueOfStructEntry(
249 thread,
250 JavaThread::suspend_flags_offset(),
251 SharkType::jint_type(),
252 "thread_state");
253
254 builder()->CreateCondBr(
255 builder()->CreateICmpNE(
256 thread_state,
257 LLVMValue::jint_constant(0)),
258 do_safepoint, safepointed);
259
260 builder()->SetInsertPoint(do_safepoint);
261 builder()->CreateCall(
262 builder()->check_special_condition_for_native_trans(), thread);
263 builder()->CreateBr(safepointed);
264
265 // Finally we can change the thread state to _thread_in_Java
266 builder()->SetInsertPoint(safepointed);
267 CreateSetThreadState(_thread_in_Java);
268
269 // Clear the frame anchor
270 stack()->CreateResetLastJavaFrame();
271
272 // If there is a pending exception then we can just unwind and
273 // return. It seems totally wrong that unlocking is skipped here
274 // but apparently the template interpreter does this so we do too.
275 BasicBlock *exception = CreateBlock("exception");
276 BasicBlock *no_exception = CreateBlock("no_exception");
277
278 builder()->CreateCondBr(
279 builder()->CreateICmpEQ(
280 CreateLoadPendingException(),
281 LLVMValue::null()),
282 no_exception, exception);
283
284 builder()->SetInsertPoint(exception);
285 CreateResetHandleBlock();
286 stack()->CreatePopFrame(0);
287 builder()->CreateRet(LLVMValue::jint_constant(0));
288
289 builder()->SetInsertPoint(no_exception);
290
291 // If the result was an oop then unbox it before
292 // releasing the handle it might be protected by
293 if (is_returning_oop()) {
294 BasicBlock *null = builder()->GetInsertBlock();
295 BasicBlock *not_null = CreateBlock("not_null");
296 BasicBlock *merge = CreateBlock("merge");
297
298 builder()->CreateCondBr(
299 builder()->CreateICmpNE(result, ConstantPointerNull::get(box_type)),
300 not_null, merge);
301
302 builder()->SetInsertPoint(not_null);
303 #error Needs to be updated for tagged jweak; see JNIHandles.
304 Value *unboxed_result = builder()->CreateLoad(result);
305 builder()->CreateBr(merge);
306
307 builder()->SetInsertPoint(merge);
308 PHINode *phi = builder()->CreatePHI(SharkType::oop_type(), 0, "result");
309 phi->addIncoming(LLVMValue::null(), null);
310 phi->addIncoming(unboxed_result, not_null);
311 result = phi;
312 }
313
314 // Reset handle block
315 CreateResetHandleBlock();
316
317 // Unlock if necessary.
318 if (is_synchronized())
319 Unimplemented();
320
321 // Unwind and return
322 Value *result_addr = stack()->CreatePopFrame(type2size[result_type]);
323 if (result_type != T_VOID) {
324 bool needs_cast = false;
325 bool is_signed = false;
326 switch (result_type) {
327 case T_BOOLEAN:
328 result = builder()->CreateICmpNE(result, LLVMValue::jbyte_constant(0));
329 needs_cast = true;
330 break;
331
332 case T_CHAR:
333 needs_cast = true;
334 break;
335
336 case T_BYTE:
337 case T_SHORT:
338 needs_cast = true;
339 is_signed = true;
340 break;
341 }
342 if (needs_cast) {
343 result = builder()->CreateIntCast(
344 result, SharkType::to_stackType(result_type), is_signed);
345 }
346
347 builder()->CreateStore(
348 result,
349 builder()->CreateIntToPtr(
350 result_addr,
351 PointerType::getUnqual(SharkType::to_stackType(result_type))));
352 }
353 builder()->CreateRet(LLVMValue::jint_constant(0));
354 }