Source.cpp revision a4ded1373d7ad3e503f186e65bccf94126a0f020 
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/IR/LLVMContext.h>
23#include <llvm/IR/Module.h>
24#include <llvm/IR/Verifier.h>
25#include <llvm/Linker/Linker.h>
26#include <llvm/Support/MemoryBuffer.h>
27#include "llvm/Support/raw_ostream.h"
28
29#include "bcc/BCCContext.h"
30#include "bcc/Support/Log.h"
31
32#include "BCCContextImpl.h"
33
34namespace {
35
36// Helper function to load the bitcode. This uses "bitcode lazy load" feature to
37// reduce the startup time. On success, return the LLVM module object created
38// and take the ownership of input memory buffer (i.e., pInput). On error,
39// return nullptr and will NOT take the ownership of pInput.
40static inline llvm::Module *helper_load_bitcode(llvm::LLVMContext &pContext,
41                                                std::unique_ptr<llvm::MemoryBuffer> &&pInput) {
42  llvm::ErrorOr<llvm::Module *> moduleOrError = llvm::getLazyBitcodeModule(std::move(pInput), pContext);
43  if (std::error_code ec = moduleOrError.getError()) {
44    ALOGE("Unable to parse the given bitcode file `%s'! (%s)",
45          pInput->getBufferIdentifier(), ec.message().c_str());
46  }
47
48  return moduleOrError.get();
49}
50
51} // end anonymous namespace
52
53namespace bcc {
54
55void Source::setModule(llvm::Module *pModule) {
56  if (!mNoDelete && (mModule != pModule)) delete mModule;
57  mModule = pModule;
58}
59
60Source *Source::CreateFromBuffer(BCCContext &pContext,
61                                 const char *pName,
62                                 const char *pBitcode,
63                                 size_t pBitcodeSize) {
64  llvm::StringRef input_data(pBitcode, pBitcodeSize);
65  std::unique_ptr<llvm::MemoryBuffer> input_memory =
66      llvm::MemoryBuffer::getMemBuffer(input_data, "", false);
67
68  if (input_memory == nullptr) {
69    ALOGE("Unable to load bitcode `%s' from buffer!", pName);
70    return nullptr;
71  }
72
73  llvm::Module *module = helper_load_bitcode(pContext.mImpl->mLLVMContext,
74                                             std::move(input_memory));
75  if (module == nullptr) {
76    return nullptr;
77  }
78
79  Source *result = CreateFromModule(pContext, pName, *module, /* pNoDelete */false);
80  if (result == nullptr) {
81    delete module;
82  }
83
84  return result;
85}
86
87Source *Source::CreateFromFile(BCCContext &pContext, const std::string &pPath) {
88
89  llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> mb_or_error =
90      llvm::MemoryBuffer::getFile(pPath);
91  if (mb_or_error.getError()) {
92    ALOGE("Failed to load bitcode from path %s! (%s)", pPath.c_str(),
93          mb_or_error.getError().message().c_str());
94    return nullptr;
95  }
96  std::unique_ptr<llvm::MemoryBuffer> input_data = std::move(mb_or_error.get());
97
98  std::unique_ptr<llvm::MemoryBuffer> input_memory(input_data.release());
99  llvm::Module *module = helper_load_bitcode(pContext.mImpl->mLLVMContext,
100                                             std::move(input_memory));
101  if (module == nullptr) {
102    return nullptr;
103  }
104
105  Source *result = CreateFromModule(pContext, pPath.c_str(), *module, /* pNoDelete */false);
106  if (result == nullptr) {
107    delete module;
108  }
109
110  return result;
111}
112
113Source *Source::CreateFromModule(BCCContext &pContext, const char* name, llvm::Module &pModule,
114                                 bool pNoDelete) {
115  std::string ErrorInfo;
116  llvm::raw_string_ostream ErrorStream(ErrorInfo);
117  if (llvm::verifyModule(pModule, &ErrorStream)) {
118    ALOGE("Bitcode of RenderScript module does not pass verification: `%s'!",
119          ErrorStream.str().c_str());
120    return nullptr;
121  }
122
123  Source *result = new (std::nothrow) Source(name, pContext, pModule, pNoDelete);
124  if (result == nullptr) {
125    ALOGE("Out of memory during Source object allocation for `%s'!",
126          pModule.getModuleIdentifier().c_str());
127  }
128  return result;
129}
130
131Source::Source(const char* name, BCCContext &pContext, llvm::Module &pModule,
132               bool pNoDelete)
133    : mName(name), mContext(pContext), mModule(&pModule), mNoDelete(pNoDelete) {
134    pContext.addSource(*this);
135}
136
137Source::~Source() {
138  mContext.removeSource(*this);
139  if (!mNoDelete)
140    delete mModule;
141}
142
143bool Source::merge(Source &pSource) {
144  // TODO(srhines): Add back logging of actual diagnostics from linking.
145  if (llvm::Linker::LinkModules(mModule, &pSource.getModule()) != 0) {
146    ALOGE("Failed to link source `%s' with `%s'!",
147          getIdentifier().c_str(), pSource.getIdentifier().c_str());
148    return false;
149  }
150
151  return true;
152}
153
154Source *Source::CreateEmpty(BCCContext &pContext, const std::string &pName) {
155  // Create an empty module
156  llvm::Module *module =
157      new (std::nothrow) llvm::Module(pName, pContext.mImpl->mLLVMContext);
158
159  if (module == nullptr) {
160    ALOGE("Out of memory when creating empty LLVM module `%s'!", pName.c_str());
161    return nullptr;
162  }
163
164  Source *result = CreateFromModule(pContext, pName.c_str(), *module, /* pNoDelete */false);
165  if (result == nullptr) {
166    delete module;
167  }
168
169  return result;
170}
171
172const std::string &Source::getIdentifier() const {
173  return mModule->getModuleIdentifier();
174}
175
176} // namespace bcc
177