1 /* 2 * Copyright 2010-2012, 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 "slang_backend.h" 18 19 #include <string> 20 #include <vector> 21 22 #include "bcinfo/BitcodeWrapper.h" 23 24 #include "clang/AST/ASTContext.h" 25 #include "clang/AST/Decl.h" 26 #include "clang/AST/DeclGroup.h" 27 28 #include "clang/Basic/Diagnostic.h" 29 #include "clang/Basic/TargetInfo.h" 30 #include "clang/Basic/TargetOptions.h" 31 32 #include "clang/CodeGen/ModuleBuilder.h" 33 34 #include "clang/Frontend/CodeGenOptions.h" 35 #include "clang/Frontend/FrontendDiagnostic.h" 36 37 #include "llvm/IR/IRPrintingPasses.h" 38 39 #include "llvm/Bitcode/ReaderWriter.h" 40 41 #include "llvm/CodeGen/RegAllocRegistry.h" 42 #include "llvm/CodeGen/SchedulerRegistry.h" 43 44 #include "llvm/IR/LLVMContext.h" 45 #include "llvm/IR/Module.h" 46 #include "llvm/IR/Metadata.h" 47 48 #include "llvm/Transforms/IPO/PassManagerBuilder.h" 49 50 #include "llvm/IR/DataLayout.h" 51 #include "llvm/Target/TargetMachine.h" 52 #include "llvm/Target/TargetOptions.h" 53 #include "llvm/Support/TargetRegistry.h" 54 55 #include "llvm/MC/SubtargetFeature.h" 56 57 #include "slang_assert.h" 58 #include "strip_unknown_attributes.h" 59 #include "BitWriter_2_9/ReaderWriter_2_9.h" 60 #include "BitWriter_2_9_func/ReaderWriter_2_9_func.h" 61 #include "BitWriter_3_2/ReaderWriter_3_2.h" 62 63 namespace slang { 64 65 void Backend::CreateFunctionPasses() { 66 if (!mPerFunctionPasses) { 67 mPerFunctionPasses = new llvm::FunctionPassManager(mpModule); 68 mPerFunctionPasses->add(new llvm::DataLayoutPass(mpModule)); 69 70 llvm::PassManagerBuilder PMBuilder; 71 PMBuilder.OptLevel = mCodeGenOpts.OptimizationLevel; 72 PMBuilder.populateFunctionPassManager(*mPerFunctionPasses); 73 } 74 } 75 76 void Backend::CreateModulePasses() { 77 if (!mPerModulePasses) { 78 mPerModulePasses = new llvm::PassManager(); 79 mPerModulePasses->add(new llvm::DataLayoutPass(mpModule)); 80 81 llvm::PassManagerBuilder PMBuilder; 82 PMBuilder.OptLevel = mCodeGenOpts.OptimizationLevel; 83 PMBuilder.SizeLevel = mCodeGenOpts.OptimizeSize; 84 if (mCodeGenOpts.UnitAtATime) { 85 PMBuilder.DisableUnitAtATime = 0; 86 } else { 87 PMBuilder.DisableUnitAtATime = 1; 88 } 89 90 if (mCodeGenOpts.UnrollLoops) { 91 PMBuilder.DisableUnrollLoops = 0; 92 } else { 93 PMBuilder.DisableUnrollLoops = 1; 94 } 95 96 PMBuilder.populateModulePassManager(*mPerModulePasses); 97 // Add a pass to strip off unknown/unsupported attributes. 98 mPerModulePasses->add(createStripUnknownAttributesPass()); 99 } 100 } 101 102 bool Backend::CreateCodeGenPasses() { 103 if ((mOT != Slang::OT_Assembly) && (mOT != Slang::OT_Object)) 104 return true; 105 106 // Now we add passes for code emitting 107 if (mCodeGenPasses) { 108 return true; 109 } else { 110 mCodeGenPasses = new llvm::FunctionPassManager(mpModule); 111 mCodeGenPasses->add(new llvm::DataLayoutPass(mpModule)); 112 } 113 114 // Create the TargetMachine for generating code. 115 std::string Triple = mpModule->getTargetTriple(); 116 117 std::string Error; 118 const llvm::Target* TargetInfo = 119 llvm::TargetRegistry::lookupTarget(Triple, Error); 120 if (TargetInfo == NULL) { 121 mDiagEngine.Report(clang::diag::err_fe_unable_to_create_target) << Error; 122 return false; 123 } 124 125 // Target Machine Options 126 llvm::TargetOptions Options; 127 128 Options.NoFramePointerElim = mCodeGenOpts.DisableFPElim; 129 130 // Use hardware FPU. 131 // 132 // FIXME: Need to detect the CPU capability and decide whether to use softfp. 133 // To use softfp, change following 2 lines to 134 // 135 // Options.FloatABIType = llvm::FloatABI::Soft; 136 // Options.UseSoftFloat = true; 137 Options.FloatABIType = llvm::FloatABI::Hard; 138 Options.UseSoftFloat = false; 139 140 // BCC needs all unknown symbols resolved at compilation time. So we don't 141 // need any relocation model. 142 llvm::Reloc::Model RM = llvm::Reloc::Static; 143 144 // This is set for the linker (specify how large of the virtual addresses we 145 // can access for all unknown symbols.) 146 llvm::CodeModel::Model CM; 147 if (mpModule->getDataLayout()->getPointerSize() == 4) { 148 CM = llvm::CodeModel::Small; 149 } else { 150 // The target may have pointer size greater than 32 (e.g. x86_64 151 // architecture) may need large data address model 152 CM = llvm::CodeModel::Medium; 153 } 154 155 // Setup feature string 156 std::string FeaturesStr; 157 if (mTargetOpts.CPU.size() || mTargetOpts.Features.size()) { 158 llvm::SubtargetFeatures Features; 159 160 for (std::vector<std::string>::const_iterator 161 I = mTargetOpts.Features.begin(), E = mTargetOpts.Features.end(); 162 I != E; 163 I++) 164 Features.AddFeature(*I); 165 166 FeaturesStr = Features.getString(); 167 } 168 169 llvm::TargetMachine *TM = 170 TargetInfo->createTargetMachine(Triple, mTargetOpts.CPU, FeaturesStr, 171 Options, RM, CM); 172 173 // Register scheduler 174 llvm::RegisterScheduler::setDefault(llvm::createDefaultScheduler); 175 176 // Register allocation policy: 177 // createFastRegisterAllocator: fast but bad quality 178 // createGreedyRegisterAllocator: not so fast but good quality 179 llvm::RegisterRegAlloc::setDefault((mCodeGenOpts.OptimizationLevel == 0) ? 180 llvm::createFastRegisterAllocator : 181 llvm::createGreedyRegisterAllocator); 182 183 llvm::CodeGenOpt::Level OptLevel = llvm::CodeGenOpt::Default; 184 if (mCodeGenOpts.OptimizationLevel == 0) { 185 OptLevel = llvm::CodeGenOpt::None; 186 } else if (mCodeGenOpts.OptimizationLevel == 3) { 187 OptLevel = llvm::CodeGenOpt::Aggressive; 188 } 189 190 llvm::TargetMachine::CodeGenFileType CGFT = 191 llvm::TargetMachine::CGFT_AssemblyFile; 192 if (mOT == Slang::OT_Object) { 193 CGFT = llvm::TargetMachine::CGFT_ObjectFile; 194 } 195 if (TM->addPassesToEmitFile(*mCodeGenPasses, FormattedOutStream, 196 CGFT, OptLevel)) { 197 mDiagEngine.Report(clang::diag::err_fe_unable_to_interface_with_target); 198 return false; 199 } 200 201 return true; 202 } 203 204 Backend::Backend(clang::DiagnosticsEngine *DiagEngine, 205 const clang::CodeGenOptions &CodeGenOpts, 206 const clang::TargetOptions &TargetOpts, 207 PragmaList *Pragmas, 208 llvm::raw_ostream *OS, 209 Slang::OutputType OT) 210 : ASTConsumer(), 211 mTargetOpts(TargetOpts), 212 mpModule(NULL), 213 mpOS(OS), 214 mOT(OT), 215 mGen(NULL), 216 mPerFunctionPasses(NULL), 217 mPerModulePasses(NULL), 218 mCodeGenPasses(NULL), 219 mLLVMContext(llvm::getGlobalContext()), 220 mDiagEngine(*DiagEngine), 221 mCodeGenOpts(CodeGenOpts), 222 mPragmas(Pragmas) { 223 FormattedOutStream.setStream(*mpOS, 224 llvm::formatted_raw_ostream::PRESERVE_STREAM); 225 mGen = CreateLLVMCodeGen(mDiagEngine, "", mCodeGenOpts, 226 mTargetOpts, mLLVMContext); 227 } 228 229 void Backend::Initialize(clang::ASTContext &Ctx) { 230 mGen->Initialize(Ctx); 231 232 mpModule = mGen->GetModule(); 233 } 234 235 // Encase the Bitcode in a wrapper containing RS version information. 236 void Backend::WrapBitcode(llvm::raw_string_ostream &Bitcode) { 237 bcinfo::AndroidBitcodeWrapper wrapper; 238 size_t actualWrapperLen = bcinfo::writeAndroidBitcodeWrapper( 239 &wrapper, Bitcode.str().length(), getTargetAPI(), 240 SlangVersion::CURRENT, mCodeGenOpts.OptimizationLevel); 241 242 slangAssert(actualWrapperLen > 0); 243 244 // Write out the bitcode wrapper. 245 FormattedOutStream.write(reinterpret_cast<char*>(&wrapper), actualWrapperLen); 246 247 // Write out the actual encoded bitcode. 248 FormattedOutStream << Bitcode.str(); 249 } 250 251 bool Backend::HandleTopLevelDecl(clang::DeclGroupRef D) { 252 return mGen->HandleTopLevelDecl(D); 253 } 254 255 void Backend::HandleTranslationUnit(clang::ASTContext &Ctx) { 256 HandleTranslationUnitPre(Ctx); 257 258 mGen->HandleTranslationUnit(Ctx); 259 260 // Here, we complete a translation unit (whole translation unit is now in LLVM 261 // IR). Now, interact with LLVM backend to generate actual machine code (asm 262 // or machine code, whatever.) 263 264 // Silently ignore if we weren't initialized for some reason. 265 if (!mpModule) 266 return; 267 268 llvm::Module *M = mGen->ReleaseModule(); 269 if (!M) { 270 // The module has been released by IR gen on failures, do not double free. 271 mpModule = NULL; 272 return; 273 } 274 275 slangAssert(mpModule == M && 276 "Unexpected module change during LLVM IR generation"); 277 278 // Insert #pragma information into metadata section of module 279 if (!mPragmas->empty()) { 280 llvm::NamedMDNode *PragmaMetadata = 281 mpModule->getOrInsertNamedMetadata(Slang::PragmaMetadataName); 282 for (PragmaList::const_iterator I = mPragmas->begin(), E = mPragmas->end(); 283 I != E; 284 I++) { 285 llvm::SmallVector<llvm::Value*, 2> Pragma; 286 // Name goes first 287 Pragma.push_back(llvm::MDString::get(mLLVMContext, I->first)); 288 // And then value 289 Pragma.push_back(llvm::MDString::get(mLLVMContext, I->second)); 290 291 // Create MDNode and insert into PragmaMetadata 292 PragmaMetadata->addOperand( 293 llvm::MDNode::get(mLLVMContext, Pragma)); 294 } 295 } 296 297 HandleTranslationUnitPost(mpModule); 298 299 // Create passes for optimization and code emission 300 301 // Create and run per-function passes 302 CreateFunctionPasses(); 303 if (mPerFunctionPasses) { 304 mPerFunctionPasses->doInitialization(); 305 306 for (llvm::Module::iterator I = mpModule->begin(), E = mpModule->end(); 307 I != E; 308 I++) 309 if (!I->isDeclaration()) 310 mPerFunctionPasses->run(*I); 311 312 mPerFunctionPasses->doFinalization(); 313 } 314 315 // Create and run module passes 316 CreateModulePasses(); 317 if (mPerModulePasses) 318 mPerModulePasses->run(*mpModule); 319 320 switch (mOT) { 321 case Slang::OT_Assembly: 322 case Slang::OT_Object: { 323 if (!CreateCodeGenPasses()) 324 return; 325 326 mCodeGenPasses->doInitialization(); 327 328 for (llvm::Module::iterator I = mpModule->begin(), E = mpModule->end(); 329 I != E; 330 I++) 331 if (!I->isDeclaration()) 332 mCodeGenPasses->run(*I); 333 334 mCodeGenPasses->doFinalization(); 335 break; 336 } 337 case Slang::OT_LLVMAssembly: { 338 llvm::PassManager *LLEmitPM = new llvm::PassManager(); 339 LLEmitPM->add(llvm::createPrintModulePass(FormattedOutStream)); 340 LLEmitPM->run(*mpModule); 341 break; 342 } 343 case Slang::OT_Bitcode: { 344 llvm::PassManager *BCEmitPM = new llvm::PassManager(); 345 std::string BCStr; 346 llvm::raw_string_ostream Bitcode(BCStr); 347 unsigned int TargetAPI = getTargetAPI(); 348 switch (TargetAPI) { 349 case SLANG_HC_TARGET_API: 350 case SLANG_HC_MR1_TARGET_API: 351 case SLANG_HC_MR2_TARGET_API: { 352 // Pre-ICS targets must use the LLVM 2.9 BitcodeWriter 353 BCEmitPM->add(llvm_2_9::createBitcodeWriterPass(Bitcode)); 354 break; 355 } 356 case SLANG_ICS_TARGET_API: 357 case SLANG_ICS_MR1_TARGET_API: { 358 // ICS targets must use the LLVM 2.9_func BitcodeWriter 359 BCEmitPM->add(llvm_2_9_func::createBitcodeWriterPass(Bitcode)); 360 break; 361 } 362 default: { 363 if (TargetAPI != SLANG_DEVELOPMENT_TARGET_API && 364 (TargetAPI < SLANG_MINIMUM_TARGET_API || 365 TargetAPI > SLANG_MAXIMUM_TARGET_API)) { 366 slangAssert(false && "Invalid target API value"); 367 } 368 // Switch to the 3.2 BitcodeWriter by default, and don't use 369 // LLVM's included BitcodeWriter at all (for now). 370 BCEmitPM->add(llvm_3_2::createBitcodeWriterPass(Bitcode)); 371 //BCEmitPM->add(llvm::createBitcodeWriterPass(Bitcode)); 372 break; 373 } 374 } 375 376 BCEmitPM->run(*mpModule); 377 WrapBitcode(Bitcode); 378 break; 379 } 380 case Slang::OT_Nothing: { 381 return; 382 } 383 default: { 384 slangAssert(false && "Unknown output type"); 385 } 386 } 387 388 FormattedOutStream.flush(); 389 } 390 391 void Backend::HandleTagDeclDefinition(clang::TagDecl *D) { 392 mGen->HandleTagDeclDefinition(D); 393 } 394 395 void Backend::CompleteTentativeDefinition(clang::VarDecl *D) { 396 mGen->CompleteTentativeDefinition(D); 397 } 398 399 Backend::~Backend() { 400 delete mpModule; 401 delete mGen; 402 delete mPerFunctionPasses; 403 delete mPerModulePasses; 404 delete mCodeGenPasses; 405 } 406 407 } // namespace slang 408