Source.cpp revision d2a5a0eab7a1273797029702652e50b2ed9e6a6d 
1/*
2 * Copyright 2012, 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 "Source.h"
18
19#include <new>
20
21#include <llvm/Bitcode/ReaderWriter.h>
22#include <llvm/LLVMContext.h>
23#include <llvm/Linker.h>
24#include <llvm/Module.h>
25#include <llvm/Support/MemoryBuffer.h>
26#include <llvm/Support/system_error.h>
27
28#include "BCCContext.h"
29#include "BCCContextImpl.h"
30#include "DebugHelper.h"
31
32namespace {
33
34// Helper function to load the bitcode. This uses "bitcode lazy load" feature to
35// reduce the startup time. On success, return the LLVM module object created
36// and take the ownership of input memory buffer (i.e., pInput). On error,
37// return NULL and will NOT take the ownership of pInput.
38static inline llvm::Module *helper_load_bitcode(llvm::LLVMContext &pContext,
39                                                llvm::MemoryBuffer *pInput) {
40  std::string error;
41  llvm::Module *module = llvm::getLazyBitcodeModule(pInput, pContext, &error);
42
43  if (module == NULL) {
44    ALOGE("Unable to parse the given bitcode file `%s'! (%s)",
45          pInput->getBufferIdentifier(), error.c_str());
46  }
47
48  return module;
49}
50
51} // end anonymous namespace
52
53namespace bcc {
54
55Source *Source::CreateFromBuffer(BCCContext &pContext,
56                                 const char *pName,
57                                 const char *pBitcode,
58                                 size_t pBitcodeSize) {
59  llvm::StringRef input_data(pBitcode, pBitcodeSize);
60  llvm::MemoryBuffer *input_memory =
61      llvm::MemoryBuffer::getMemBuffer(input_data, pName);
62
63  if (input_memory == NULL) {
64    ALOGE("Unable to load bitcode `%s' from buffer!", pName);
65    return NULL;
66  }
67
68  llvm::Module *module = helper_load_bitcode(pContext.mImpl->mLLVMContext,
69                                             input_memory);
70  if (module == NULL) {
71    delete input_memory;
72    return NULL;
73  }
74
75  Source *result = CreateFromModule(pContext, *module, /* pNoDelete */false);
76  if (result == NULL) {
77    delete module;
78  }
79
80  return result;
81}
82
83
84Source *Source::CreateFromFile(BCCContext &pContext, const std::string &pPath) {
85  llvm::OwningPtr<llvm::MemoryBuffer> input_data;
86
87  llvm::error_code ec = llvm::MemoryBuffer::getFile(pPath, input_data);
88  if (ec != llvm::error_code::success()) {
89    ALOGE("Failed to load bitcode from path %s! (%s)", pPath.c_str(),
90                                                       ec.message().c_str());
91    return NULL;
92  }
93
94  llvm::MemoryBuffer *input_memory = input_data.take();
95  llvm::Module *module = helper_load_bitcode(pContext.mImpl->mLLVMContext,
96                                             input_memory);
97  if (module == NULL) {
98    delete input_memory;
99    return NULL;
100  }
101
102  Source *result = CreateFromModule(pContext, *module, /* pNoDelete */false);
103  if (result == NULL) {
104    delete module;
105  }
106
107  return result;
108}
109
110
111Source *Source::CreateFromModule(BCCContext &pContext, llvm::Module &pModule,
112                                 bool pNoDelete) {
113  Source *result = new (std::nothrow) Source(pContext, pModule, pNoDelete);
114  if (result == NULL) {
115    ALOGE("Out of memory during Source object allocation for `%s'!",
116          pModule.getModuleIdentifier().c_str());
117  }
118  return result;
119}
120
121Source::Source(BCCContext &pContext, llvm::Module &pModule, bool pNoDelete)
122  : mContext(pContext), mModule(&pModule), mNoDelete(pNoDelete) {
123    pContext.addSource(*this);
124}
125
126Source::~Source() {
127  mContext.removeSource(*this);
128  if (!mNoDelete)
129    delete mModule;
130}
131
132bool Source::merge(Source &pSource, bool pPreserveSource) {
133  std::string error;
134  llvm::Linker::LinkerMode mode =
135      ((pPreserveSource) ? llvm::Linker::PreserveSource :
136                           llvm::Linker::DestroySource);
137
138  if (llvm::Linker::LinkModules(mModule, &pSource.getModule(),
139                                mode, &error) != 0) {
140    ALOGE("Failed to link source `%s' with `%s' (%s)!",
141          getIdentifier().c_str(),
142          pSource.getIdentifier().c_str(),
143          error.c_str());
144    return false;
145  }
146
147  if (!pPreserveSource) {
148    pSource.mNoDelete = true;
149    delete &pSource;
150  }
151
152  return true;
153}
154
155Source *Source::CreateEmpty(BCCContext &pContext, const std::string &pName) {
156  // Create an empty module
157  llvm::Module *module =
158      new (std::nothrow) llvm::Module(pName, pContext.mImpl->mLLVMContext);
159
160  if (module == NULL) {
161    ALOGE("Out of memory when creating empty LLVM module `%s'!", pName.c_str());
162    return NULL;
163  }
164
165  Source *result = CreateFromModule(pContext, *module, /* pNoDelete */false);
166  if (result == NULL) {
167    delete module;
168  }
169
170  return result;
171}
172
173const std::string &Source::getIdentifier() const {
174  return mModule->getModuleIdentifier();
175}
176
177} // namespace bcc
178