1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 # include "mir_method_info.h"
18 
19 #include "driver/compiler_driver.h"
20 #include "driver/dex_compilation_unit.h"
21 #include "driver/compiler_driver-inl.h"
22 #include "mirror/class_loader.h"  // Only to allow casts in Handle<ClassLoader>.
23 #include "mirror/dex_cache.h"     // Only to allow casts in Handle<DexCache>.
24 #include "scoped_thread_state_change.h"
25 #include "handle_scope-inl.h"
26 
27 namespace art {
28 
Resolve(CompilerDriver * compiler_driver,const DexCompilationUnit * mUnit,MirMethodLoweringInfo * method_infos,size_t count)29 void MirMethodLoweringInfo::Resolve(CompilerDriver* compiler_driver,
30                                     const DexCompilationUnit* mUnit,
31                                     MirMethodLoweringInfo* method_infos, size_t count) {
32   if (kIsDebugBuild) {
33     DCHECK(method_infos != nullptr);
34     DCHECK_NE(count, 0u);
35     for (auto it = method_infos, end = method_infos + count; it != end; ++it) {
36       MirMethodLoweringInfo unresolved(it->MethodIndex(), it->GetInvokeType());
37       if (it->target_dex_file_ != nullptr) {
38         unresolved.target_dex_file_ = it->target_dex_file_;
39         unresolved.target_method_idx_ = it->target_method_idx_;
40       }
41       DCHECK_EQ(memcmp(&unresolved, &*it, sizeof(*it)), 0);
42     }
43   }
44 
45   // We're going to resolve methods and check access in a tight loop. It's better to hold
46   // the lock and needed references once than re-acquiring them again and again.
47   ScopedObjectAccess soa(Thread::Current());
48   StackHandleScope<3> hs(soa.Self());
49   Handle<mirror::DexCache> dex_cache(hs.NewHandle(compiler_driver->GetDexCache(mUnit)));
50   Handle<mirror::ClassLoader> class_loader(
51       hs.NewHandle(compiler_driver->GetClassLoader(soa, mUnit)));
52   Handle<mirror::Class> referrer_class(hs.NewHandle(
53       compiler_driver->ResolveCompilingMethodsClass(soa, dex_cache, class_loader, mUnit)));
54   // Even if the referrer class is unresolved (i.e. we're compiling a method without class
55   // definition) we still want to resolve methods and record all available info.
56 
57   for (auto it = method_infos, end = method_infos + count; it != end; ++it) {
58     // Remember devirtualized invoke target and set the called method to the default.
59     MethodReference devirt_ref(it->target_dex_file_, it->target_method_idx_);
60     MethodReference* devirt_target = (it->target_dex_file_ != nullptr) ? &devirt_ref : nullptr;
61     it->target_dex_file_ = mUnit->GetDexFile();
62     it->target_method_idx_ = it->MethodIndex();
63 
64     InvokeType invoke_type = it->GetInvokeType();
65     mirror::ArtMethod* resolved_method =
66         compiler_driver->ResolveMethod(soa, dex_cache, class_loader, mUnit, it->MethodIndex(),
67                                        invoke_type);
68     if (UNLIKELY(resolved_method == nullptr)) {
69       continue;
70     }
71     compiler_driver->GetResolvedMethodDexFileLocation(resolved_method,
72         &it->declaring_dex_file_, &it->declaring_class_idx_, &it->declaring_method_idx_);
73     it->vtable_idx_ = compiler_driver->GetResolvedMethodVTableIndex(resolved_method, invoke_type);
74 
75     MethodReference target_method(mUnit->GetDexFile(), it->MethodIndex());
76     int fast_path_flags = compiler_driver->IsFastInvoke(
77         soa, dex_cache, class_loader, mUnit, referrer_class.Get(), resolved_method, &invoke_type,
78         &target_method, devirt_target, &it->direct_code_, &it->direct_method_);
79     bool needs_clinit =
80         compiler_driver->NeedsClassInitialization(referrer_class.Get(), resolved_method);
81     uint16_t other_flags = it->flags_ &
82         ~(kFlagFastPath | kFlagNeedsClassInitialization | (kInvokeTypeMask << kBitSharpTypeBegin));
83     it->flags_ = other_flags |
84         (fast_path_flags != 0 ? kFlagFastPath : 0u) |
85         (static_cast<uint16_t>(invoke_type) << kBitSharpTypeBegin) |
86         (needs_clinit ? kFlagNeedsClassInitialization : 0u);
87     it->target_dex_file_ = target_method.dex_file;
88     it->target_method_idx_ = target_method.dex_method_index;
89     it->stats_flags_ = fast_path_flags;
90   }
91 }
92 
93 }  // namespace art
94