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_field_info.h"
18
19#include <string.h>
20
21#include "base/logging.h"
22#include "driver/compiler_driver.h"
23#include "driver/compiler_driver-inl.h"
24#include "mirror/class_loader.h"  // Only to allow casts in Handle<ClassLoader>.
25#include "mirror/dex_cache.h"     // Only to allow casts in Handle<DexCache>.
26#include "scoped_thread_state_change.h"
27#include "handle_scope-inl.h"
28
29namespace art {
30
31void MirIFieldLoweringInfo::Resolve(CompilerDriver* compiler_driver,
32                                    const DexCompilationUnit* mUnit,
33                                    MirIFieldLoweringInfo* field_infos, size_t count) {
34  if (kIsDebugBuild) {
35    DCHECK(field_infos != nullptr);
36    DCHECK_NE(count, 0u);
37    for (auto it = field_infos, end = field_infos + count; it != end; ++it) {
38      MirIFieldLoweringInfo unresolved(it->field_idx_);
39      DCHECK_EQ(memcmp(&unresolved, &*it, sizeof(*it)), 0);
40    }
41  }
42
43  // We're going to resolve fields and check access in a tight loop. It's better to hold
44  // the lock and needed references once than re-acquiring them again and again.
45  ScopedObjectAccess soa(Thread::Current());
46  StackHandleScope<3> hs(soa.Self());
47  Handle<mirror::DexCache> dex_cache(hs.NewHandle(compiler_driver->GetDexCache(mUnit)));
48  Handle<mirror::ClassLoader> class_loader(
49      hs.NewHandle(compiler_driver->GetClassLoader(soa, mUnit)));
50  Handle<mirror::Class> referrer_class(hs.NewHandle(
51      compiler_driver->ResolveCompilingMethodsClass(soa, dex_cache, class_loader, mUnit)));
52  // Even if the referrer class is unresolved (i.e. we're compiling a method without class
53  // definition) we still want to resolve fields and record all available info.
54
55  for (auto it = field_infos, end = field_infos + count; it != end; ++it) {
56    uint32_t field_idx = it->field_idx_;
57    mirror::ArtField* resolved_field =
58        compiler_driver->ResolveField(soa, dex_cache, class_loader, mUnit, field_idx, false);
59    if (UNLIKELY(resolved_field == nullptr)) {
60      continue;
61    }
62    compiler_driver->GetResolvedFieldDexFileLocation(resolved_field,
63        &it->declaring_dex_file_, &it->declaring_class_idx_, &it->declaring_field_idx_);
64    bool is_volatile = compiler_driver->IsFieldVolatile(resolved_field);
65    it->field_offset_ = resolved_field->GetOffset();
66    std::pair<bool, bool> fast_path = compiler_driver->IsFastInstanceField(
67        dex_cache.Get(), referrer_class.Get(), resolved_field, field_idx);
68    it->flags_ = 0u |  // Without kFlagIsStatic.
69        (is_volatile ? kFlagIsVolatile : 0u) |
70        (fast_path.first ? kFlagFastGet : 0u) |
71        (fast_path.second ? kFlagFastPut : 0u);
72  }
73}
74
75void MirSFieldLoweringInfo::Resolve(CompilerDriver* compiler_driver,
76                                    const DexCompilationUnit* mUnit,
77                                    MirSFieldLoweringInfo* field_infos, size_t count) {
78  if (kIsDebugBuild) {
79    DCHECK(field_infos != nullptr);
80    DCHECK_NE(count, 0u);
81    for (auto it = field_infos, end = field_infos + count; it != end; ++it) {
82      MirSFieldLoweringInfo unresolved(it->field_idx_);
83      // In 64-bit builds, there's padding after storage_index_, don't include it in memcmp.
84      size_t size = OFFSETOF_MEMBER(MirSFieldLoweringInfo, storage_index_) +
85          sizeof(it->storage_index_);
86      DCHECK_EQ(memcmp(&unresolved, &*it, size), 0);
87    }
88  }
89
90  // We're going to resolve fields and check access in a tight loop. It's better to hold
91  // the lock and needed references once than re-acquiring them again and again.
92  ScopedObjectAccess soa(Thread::Current());
93  StackHandleScope<3> hs(soa.Self());
94  Handle<mirror::DexCache> dex_cache(hs.NewHandle(compiler_driver->GetDexCache(mUnit)));
95  Handle<mirror::ClassLoader> class_loader(
96      hs.NewHandle(compiler_driver->GetClassLoader(soa, mUnit)));
97  Handle<mirror::Class> referrer_class(hs.NewHandle(
98      compiler_driver->ResolveCompilingMethodsClass(soa, dex_cache, class_loader, mUnit)));
99  // Even if the referrer class is unresolved (i.e. we're compiling a method without class
100  // definition) we still want to resolve fields and record all available info.
101
102  for (auto it = field_infos, end = field_infos + count; it != end; ++it) {
103    uint32_t field_idx = it->field_idx_;
104    mirror::ArtField* resolved_field =
105        compiler_driver->ResolveField(soa, dex_cache, class_loader, mUnit, field_idx, true);
106    if (UNLIKELY(resolved_field == nullptr)) {
107      continue;
108    }
109    compiler_driver->GetResolvedFieldDexFileLocation(resolved_field,
110        &it->declaring_dex_file_, &it->declaring_class_idx_, &it->declaring_field_idx_);
111    bool is_volatile = compiler_driver->IsFieldVolatile(resolved_field) ? 1u : 0u;
112
113    bool is_referrers_class, is_initialized;
114    std::pair<bool, bool> fast_path = compiler_driver->IsFastStaticField(
115        dex_cache.Get(), referrer_class.Get(), resolved_field, field_idx, &it->field_offset_,
116        &it->storage_index_, &is_referrers_class, &is_initialized);
117    it->flags_ = kFlagIsStatic |
118        (is_volatile ? kFlagIsVolatile : 0u) |
119        (fast_path.first ? kFlagFastGet : 0u) |
120        (fast_path.second ? kFlagFastPut : 0u) |
121        (is_referrers_class ? kFlagIsReferrersClass : 0u) |
122        (is_initialized ? kFlagIsInitialized : 0u);
123  }
124}
125
126}  // namespace art
127