Source.cpp revision 5b948190e3b311d06526addbb8f0e77a76da2467 
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 "bcc/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 "bcc/BCCContext.h"
29#include "bcc/Support/DebugHelper.h"
30
31#include "BCCContextImpl.h"
32
33namespace {
34
35// Helper function to load the bitcode. This uses "bitcode lazy load" feature to
36// reduce the startup time. On success, return the LLVM module object created
37// and take the ownership of input memory buffer (i.e., pInput). On error,
38// return NULL and will NOT take the ownership of pInput.
39static inline llvm::Module *helper_load_bitcode(llvm::LLVMContext &pContext,
40                                                llvm::MemoryBuffer *pInput) {
41  std::string error;
42  llvm::Module *module = llvm::getLazyBitcodeModule(pInput, pContext, &error);
43
44  if (module == NULL) {
45    ALOGE("Unable to parse the given bitcode file `%s'! (%s)",
46          pInput->getBufferIdentifier(), error.c_str());
47  }
48
49  return module;
50}
51
52} // end anonymous namespace
53
54namespace bcc {
55
56Source *Source::CreateFromBuffer(BCCContext &pContext,
57                                 const char *pName,
58                                 const char *pBitcode,
59                                 size_t pBitcodeSize) {
60  llvm::StringRef input_data(pBitcode, pBitcodeSize);
61  llvm::MemoryBuffer *input_memory =
62      llvm::MemoryBuffer::getMemBuffer(input_data, pName);
63
64  if (input_memory == NULL) {
65    ALOGE("Unable to load bitcode `%s' from buffer!", pName);
66    return NULL;
67  }
68
69  llvm::Module *module = helper_load_bitcode(pContext.mImpl->mLLVMContext,
70                                             input_memory);
71  if (module == NULL) {
72    delete input_memory;
73    return NULL;
74  }
75
76  Source *result = CreateFromModule(pContext, *module, /* pNoDelete */false);
77  if (result == NULL) {
78    delete module;
79  }
80
81  return result;
82}
83
84
85Source *Source::CreateFromFile(BCCContext &pContext, const std::string &pPath) {
86  llvm::OwningPtr<llvm::MemoryBuffer> input_data;
87
88  llvm::error_code ec = llvm::MemoryBuffer::getFile(pPath, input_data);
89  if (ec != llvm::error_code::success()) {
90    ALOGE("Failed to load bitcode from path %s! (%s)", pPath.c_str(),
91                                                       ec.message().c_str());
92    return NULL;
93  }
94
95  llvm::MemoryBuffer *input_memory = input_data.take();
96  llvm::Module *module = helper_load_bitcode(pContext.mImpl->mLLVMContext,
97                                             input_memory);
98  if (module == NULL) {
99    delete input_memory;
100    return NULL;
101  }
102
103  Source *result = CreateFromModule(pContext, *module, /* pNoDelete */false);
104  if (result == NULL) {
105    delete module;
106  }
107
108  return result;
109}
110
111
112Source *Source::CreateFromModule(BCCContext &pContext, llvm::Module &pModule,
113                                 bool pNoDelete) {
114  Source *result = new (std::nothrow) Source(pContext, pModule, pNoDelete);
115  if (result == NULL) {
116    ALOGE("Out of memory during Source object allocation for `%s'!",
117          pModule.getModuleIdentifier().c_str());
118  }
119  return result;
120}
121
122Source::Source(BCCContext &pContext, llvm::Module &pModule, bool pNoDelete)
123  : mContext(pContext), mModule(&pModule), mNoDelete(pNoDelete) {
124    pContext.addSource(*this);
125}
126
127Source::~Source() {
128  mContext.removeSource(*this);
129  if (!mNoDelete)
130    delete mModule;
131}
132
133bool Source::merge(Source &pSource, bool pPreserveSource) {
134  std::string error;
135  llvm::Linker::LinkerMode mode =
136      ((pPreserveSource) ? llvm::Linker::PreserveSource :
137                           llvm::Linker::DestroySource);
138
139  if (llvm::Linker::LinkModules(mModule, &pSource.getModule(),
140                                mode, &error) != 0) {
141    ALOGE("Failed to link source `%s' with `%s' (%s)!",
142          getIdentifier().c_str(),
143          pSource.getIdentifier().c_str(),
144          error.c_str());
145    return false;
146  }
147
148  if (!pPreserveSource) {
149    pSource.mNoDelete = true;
150    delete &pSource;
151  }
152
153  return true;
154}
155
156Source *Source::CreateEmpty(BCCContext &pContext, const std::string &pName) {
157  // Create an empty module
158  llvm::Module *module =
159      new (std::nothrow) llvm::Module(pName, pContext.mImpl->mLLVMContext);
160
161  if (module == NULL) {
162    ALOGE("Out of memory when creating empty LLVM module `%s'!", pName.c_str());
163    return NULL;
164  }
165
166  Source *result = CreateFromModule(pContext, *module, /* pNoDelete */false);
167  if (result == NULL) {
168    delete module;
169  }
170
171  return result;
172}
173
174const std::string &Source::getIdentifier() const {
175  return mModule->getModuleIdentifier();
176}
177
178} // namespace bcc
179