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#include "BitWriter_3_2/ReaderWriter_3_2.h" 25 26#define LOG_TAG "bcinfo" 27#include <cutils/log.h> 28 29#include "llvm/Bitcode/BitstreamWriter.h" 30#include "llvm/Bitcode/ReaderWriter.h" 31#include "llvm/IR/LLVMContext.h" 32#include "llvm/IR/Module.h" 33#include "llvm/Support/MemoryBuffer.h" 34#include "llvm/Support/raw_ostream.h" 35 36#include <cstdlib> 37#include <climits> 38 39namespace bcinfo { 40 41/** 42 * Define minimum and maximum target API versions. These correspond to the 43 * same API levels used by the standard Android SDK. 44 * 45 * LLVM 2.7 46 * 11 - Honeycomb 47 * 12 - Honeycomb MR1 48 * 13 - Honeycomb MR2 49 * 50 * LLVM 3.0 51 * 14 - Ice Cream Sandwich 52 * 15 - Ice Cream Sandwich MR1 53 * 54 * LLVM 3.1 55 * 16 - Ice Cream Sandwich MR2 56 */ 57static const unsigned int kMinimumAPIVersion = 11; 58static const unsigned int kMaximumAPIVersion = RS_VERSION; 59static const unsigned int kCurrentAPIVersion = 10000; 60static const unsigned int kDevelopmentAPIVersion = UINT_MAX; 61 62/** 63 * The minimum version which does not require translation (i.e. is already 64 * compatible with LLVM's default bitcode reader). 65 */ 66static const unsigned int kMinimumUntranslatedVersion = 16; 67static const unsigned int kMinimumCompatibleVersion_LLVM_3_0 = 14; 68static const unsigned int kMinimumCompatibleVersion_LLVM_2_7 = 11; 69 70 71BitcodeTranslator::BitcodeTranslator(const char *bitcode, size_t bitcodeSize, 72 unsigned int version) 73 : mBitcode(bitcode), mBitcodeSize(bitcodeSize), mTranslatedBitcode(nullptr), 74 mTranslatedBitcodeSize(0), mVersion(version) { 75 return; 76} 77 78 79BitcodeTranslator::~BitcodeTranslator() { 80 if (mVersion < kMinimumUntranslatedVersion) { 81 // We didn't actually do a translation in the alternate case, so deleting 82 // the bitcode would be improper. 83 delete [] mTranslatedBitcode; 84 } 85 mTranslatedBitcode = nullptr; 86 return; 87} 88 89 90bool BitcodeTranslator::translate() { 91 if (!mBitcode || !mBitcodeSize) { 92 ALOGE("Invalid/empty bitcode"); 93 return false; 94 } 95 96 BitcodeWrapper BCWrapper(mBitcode, mBitcodeSize); 97 if (BCWrapper.getTargetAPI() != mVersion) { 98 ALOGE("Bitcode wrapper (%u) and translator (%u) disagree about target API", 99 BCWrapper.getTargetAPI(), mVersion); 100 } 101 102 if ((mVersion != kDevelopmentAPIVersion) && 103 (mVersion != kCurrentAPIVersion) && 104 ((mVersion < kMinimumAPIVersion) || 105 (mVersion > kMaximumAPIVersion))) { 106 ALOGE("Invalid API version: %u is out of range ('%u' - '%u')", mVersion, 107 kMinimumAPIVersion, kMaximumAPIVersion); 108 return false; 109 } 110 111 // We currently don't need to transcode any API version higher than 14 or 112 // the current API version (i.e. 10000) 113 if (mVersion >= kMinimumUntranslatedVersion) { 114 mTranslatedBitcode = mBitcode; 115 mTranslatedBitcodeSize = mBitcodeSize; 116 return true; 117 } 118 119 // Do the actual transcoding by invoking a 2.7-era bitcode reader that can 120 // then write the bitcode back out in a more modern (acceptable) version. 121 std::unique_ptr<llvm::LLVMContext> mContext(new llvm::LLVMContext()); 122 std::unique_ptr<llvm::MemoryBuffer> MEM( 123 llvm::MemoryBuffer::getMemBuffer( 124 llvm::StringRef(mBitcode, mBitcodeSize), "", false)); 125 std::string error; 126 llvm::ErrorOr<llvm::MemoryBufferRef> MBOrErr = MEM->getMemBufferRef(); 127 128 llvm::ErrorOr<llvm::Module *> MOrErr(nullptr); 129 130 if (mVersion >= kMinimumCompatibleVersion_LLVM_3_0) { 131 MOrErr = llvm_3_0::parseBitcodeFile(*MBOrErr, *mContext); 132 } else if (mVersion >= kMinimumCompatibleVersion_LLVM_2_7) { 133 MOrErr = llvm_2_7::parseBitcodeFile(*MBOrErr, *mContext); 134 } else { 135 ALOGE("No compatible bitcode reader for API version %d", mVersion); 136 return false; 137 } 138 139 if (std::error_code EC = MOrErr.getError()) { 140 ALOGE("Could not parse bitcode file"); 141 ALOGE("%s", EC.message().c_str()); 142 return false; 143 } 144 145 // Module ownership is handled by the context, so we don't need to free it. 146 llvm::Module *module = MOrErr.get(); 147 148 std::string Buffer; 149 150 llvm::raw_string_ostream OS(Buffer); 151 // Use the LLVM 3.2 bitcode writer, instead of the top-of-tree version. 152 llvm_3_2::WriteBitcodeToFile(module, OS); 153 OS.flush(); 154 155 AndroidBitcodeWrapper wrapper; 156 size_t actualWrapperLen = writeAndroidBitcodeWrapper( 157 &wrapper, Buffer.size(), kMinimumUntranslatedVersion, 158 BCWrapper.getCompilerVersion(), BCWrapper.getOptimizationLevel()); 159 if (!actualWrapperLen) { 160 ALOGE("Couldn't produce bitcode wrapper!"); 161 return false; 162 } 163 164 mTranslatedBitcodeSize = actualWrapperLen + Buffer.size(); 165 char *c = new char[mTranslatedBitcodeSize]; 166 memcpy(c, &wrapper, actualWrapperLen); 167 memcpy(c + actualWrapperLen, Buffer.c_str(), Buffer.size()); 168 169 mTranslatedBitcode = c; 170 171 return true; 172} 173 174} // namespace bcinfo 175