1/* 2 * Copyright 2011-2012, 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 "bcinfo/BitcodeTranslator.h" 18 19#include "bcinfo/BitcodeWrapper.h" 20 21#include "BitReader_2_7/BitReader_2_7.h" 22#include "BitReader_3_0/BitReader_3_0.h" 23 24#define LOG_TAG "bcinfo" 25#include <cutils/log.h> 26 27#include "llvm/ADT/OwningPtr.h" 28#include "llvm/Bitcode/BitstreamWriter.h" 29#include "llvm/Bitcode/ReaderWriter.h" 30#include "llvm/LLVMContext.h" 31#include "llvm/Module.h" 32#include "llvm/Support/MemoryBuffer.h" 33#include "llvm/Support/raw_ostream.h" 34 35#include <cstdlib> 36 37namespace bcinfo { 38 39/** 40 * Define minimum and maximum target API versions. These correspond to the 41 * same API levels used by the standard Android SDK. 42 * 43 * LLVM 2.7 44 * 11 - Honeycomb 45 * 12 - Honeycomb MR1 46 * 13 - Honeycomb MR2 47 * 48 * LLVM 3.0 49 * 14 - Ice Cream Sandwich 50 * 15 - Ice Cream Sandwich MR1 51 * 52 * LLVM 3.1 53 * 16 - Ice Cream Sandwich MR2 54 */ 55static const unsigned int kMinimumAPIVersion = 11; 56static const unsigned int kMaximumAPIVersion = BCINFO_API_VERSION; 57static const unsigned int kCurrentAPIVersion = 10000; 58 59/** 60 * The minimum version which does not require translation (i.e. is already 61 * compatible with LLVM's default bitcode reader). 62 */ 63static const unsigned int kMinimumUntranslatedVersion = 16; 64static const unsigned int kMinimumCompatibleVersion_LLVM_3_0 = 14; 65static const unsigned int kMinimumCompatibleVersion_LLVM_2_7 = 11; 66 67 68BitcodeTranslator::BitcodeTranslator(const char *bitcode, size_t bitcodeSize, 69 unsigned int version) 70 : mBitcode(bitcode), mBitcodeSize(bitcodeSize), mTranslatedBitcode(NULL), 71 mTranslatedBitcodeSize(0), mVersion(version) { 72 return; 73} 74 75 76BitcodeTranslator::~BitcodeTranslator() { 77 if (mVersion < kMinimumUntranslatedVersion) { 78 // We didn't actually do a translation in the alternate case, so deleting 79 // the bitcode would be improper. 80 delete [] mTranslatedBitcode; 81 } 82 mTranslatedBitcode = NULL; 83 return; 84} 85 86 87bool BitcodeTranslator::translate() { 88 if (!mBitcode || !mBitcodeSize) { 89 ALOGE("Invalid/empty bitcode"); 90 return false; 91 } 92 93 BitcodeWrapper BCWrapper(mBitcode, mBitcodeSize); 94 if (BCWrapper.getTargetAPI() != mVersion) { 95 ALOGE("Bitcode wrapper (%u) and translator (%u) disagree about target API", 96 BCWrapper.getTargetAPI(), mVersion); 97 } 98 99 if ((mVersion != kCurrentAPIVersion) && 100 ((mVersion < kMinimumAPIVersion) || 101 (mVersion > kMaximumAPIVersion))) { 102 ALOGE("Invalid API version: %u is out of range ('%u' - '%u')", mVersion, 103 kMinimumAPIVersion, kMaximumAPIVersion); 104 return false; 105 } 106 107 // We currently don't need to transcode any API version higher than 14 or 108 // the current API version (i.e. 10000) 109 if (mVersion >= kMinimumUntranslatedVersion) { 110 mTranslatedBitcode = mBitcode; 111 mTranslatedBitcodeSize = mBitcodeSize; 112 return true; 113 } 114 115 // Do the actual transcoding by invoking a 2.7-era bitcode reader that can 116 // then write the bitcode back out in a more modern (acceptable) version. 117 llvm::OwningPtr<llvm::LLVMContext> mContext(new llvm::LLVMContext()); 118 llvm::OwningPtr<llvm::MemoryBuffer> MEM( 119 llvm::MemoryBuffer::getMemBuffer( 120 llvm::StringRef(mBitcode, mBitcodeSize), "", false)); 121 std::string error; 122 123 // Module ownership is handled by the context, so we don't need to free it. 124 llvm::Module *module = NULL; 125 126 if (mVersion >= kMinimumCompatibleVersion_LLVM_3_0) { 127 module = llvm_3_0::ParseBitcodeFile(MEM.get(), *mContext, &error); 128 } else if (mVersion >= kMinimumCompatibleVersion_LLVM_2_7) { 129 module = llvm_2_7::ParseBitcodeFile(MEM.get(), *mContext, &error); 130 } else { 131 ALOGE("No compatible bitcode reader for API version %d", mVersion); 132 return false; 133 } 134 135 if (!module) { 136 ALOGE("Could not parse bitcode file"); 137 ALOGE("%s", error.c_str()); 138 return false; 139 } 140 141 std::string Buffer; 142 143 llvm::raw_string_ostream OS(Buffer); 144 llvm::WriteBitcodeToFile(module, OS); 145 OS.flush(); 146 147 AndroidBitcodeWrapper wrapper; 148 size_t actualWrapperLen = writeAndroidBitcodeWrapper( 149 &wrapper, Buffer.size(), BCWrapper.getTargetAPI(), 150 BCWrapper.getCompilerVersion(), BCWrapper.getOptimizationLevel()); 151 if (!actualWrapperLen) { 152 ALOGE("Couldn't produce bitcode wrapper!"); 153 return false; 154 } 155 156 mTranslatedBitcodeSize = actualWrapperLen + Buffer.size(); 157 char *c = new char[mTranslatedBitcodeSize]; 158 memcpy(c, &wrapper, actualWrapperLen); 159 memcpy(c + actualWrapperLen, Buffer.c_str(), Buffer.size()); 160 161 mTranslatedBitcode = c; 162 163 return true; 164} 165 166} // namespace bcinfo 167 168