slang_backend.cpp revision c460b37ffb50819a32c2a8967754b6f784b28263
1/* 2 * Copyright 2010, 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/Assembly/PrintModulePass.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/LLVMContext.h" 45#include "llvm/Module.h" 46#include "llvm/Metadata.h" 47 48#include "llvm/Transforms/IPO/PassManagerBuilder.h" 49 50#include "llvm/Target/TargetData.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 "BitWriter_2_9/ReaderWriter_2_9.h" 59 60namespace slang { 61 62void Backend::CreateFunctionPasses() { 63 if (!mPerFunctionPasses) { 64 mPerFunctionPasses = new llvm::FunctionPassManager(mpModule); 65 mPerFunctionPasses->add(new llvm::TargetData(mpModule)); 66 67 llvm::PassManagerBuilder PMBuilder; 68 PMBuilder.OptLevel = mCodeGenOpts.OptimizationLevel; 69 PMBuilder.populateFunctionPassManager(*mPerFunctionPasses); 70 } 71 return; 72} 73 74void Backend::CreateModulePasses() { 75 if (!mPerModulePasses) { 76 mPerModulePasses = new llvm::PassManager(); 77 mPerModulePasses->add(new llvm::TargetData(mpModule)); 78 79 llvm::PassManagerBuilder PMBuilder; 80 PMBuilder.OptLevel = mCodeGenOpts.OptimizationLevel; 81 PMBuilder.SizeLevel = mCodeGenOpts.OptimizeSize; 82 PMBuilder.SizeLevel = mCodeGenOpts.OptimizeSize; 83 if (mCodeGenOpts.UnitAtATime) { 84 PMBuilder.DisableUnitAtATime = 0; 85 } else { 86 PMBuilder.DisableUnitAtATime = 1; 87 } 88 89 if (mCodeGenOpts.UnrollLoops) { 90 PMBuilder.DisableUnrollLoops = 0; 91 } else { 92 PMBuilder.DisableUnrollLoops = 1; 93 } 94 95 PMBuilder.DisableSimplifyLibCalls = false; 96 PMBuilder.populateModulePassManager(*mPerModulePasses); 97 } 98 return; 99} 100 101bool Backend::CreateCodeGenPasses() { 102 if ((mOT != Slang::OT_Assembly) && (mOT != Slang::OT_Object)) 103 return true; 104 105 // Now we add passes for code emitting 106 if (mCodeGenPasses) { 107 return true; 108 } else { 109 mCodeGenPasses = new llvm::FunctionPassManager(mpModule); 110 mCodeGenPasses->add(new llvm::TargetData(mpModule)); 111 } 112 113 // Create the TargetMachine for generating code. 114 std::string Triple = mpModule->getTargetTriple(); 115 116 std::string Error; 117 const llvm::Target* TargetInfo = 118 llvm::TargetRegistry::lookupTarget(Triple, Error); 119 if (TargetInfo == NULL) { 120 mDiagEngine.Report(clang::diag::err_fe_unable_to_create_target) << Error; 121 return false; 122 } 123 124 llvm::NoFramePointerElim = mCodeGenOpts.DisableFPElim; 125 126 // Use hardware FPU. 127 // 128 // FIXME: Need to detect the CPU capability and decide whether to use softfp. 129 // To use softfp, change following 2 lines to 130 // 131 // llvm::FloatABIType = llvm::FloatABI::Soft; 132 // llvm::UseSoftFloat = true; 133 llvm::FloatABIType = llvm::FloatABI::Hard; 134 llvm::UseSoftFloat = false; 135 136 // BCC needs all unknown symbols resolved at compilation time. So we don't 137 // need any relocation model. 138 llvm::Reloc::Model RM = llvm::Reloc::Static; 139 140 // This is set for the linker (specify how large of the virtual addresses we 141 // can access for all unknown symbols.) 142 llvm::CodeModel::Model CM; 143 if (mpModule->getPointerSize() == llvm::Module::Pointer32) { 144 CM = llvm::CodeModel::Small; 145 } else { 146 // The target may have pointer size greater than 32 (e.g. x86_64 147 // architecture) may need large data address model 148 CM = llvm::CodeModel::Medium; 149 } 150 151 // Setup feature string 152 std::string FeaturesStr; 153 if (mTargetOpts.CPU.size() || mTargetOpts.Features.size()) { 154 llvm::SubtargetFeatures Features; 155 156 for (std::vector<std::string>::const_iterator 157 I = mTargetOpts.Features.begin(), E = mTargetOpts.Features.end(); 158 I != E; 159 I++) 160 Features.AddFeature(*I); 161 162 FeaturesStr = Features.getString(); 163 } 164 165 llvm::TargetMachine *TM = 166 TargetInfo->createTargetMachine(Triple, mTargetOpts.CPU, FeaturesStr, 167 RM, CM); 168 169 // Register scheduler 170 llvm::RegisterScheduler::setDefault(llvm::createDefaultScheduler); 171 172 // Register allocation policy: 173 // createFastRegisterAllocator: fast but bad quality 174 // createLinearScanRegisterAllocator: not so fast but good quality 175 llvm::RegisterRegAlloc::setDefault((mCodeGenOpts.OptimizationLevel == 0) ? 176 llvm::createFastRegisterAllocator : 177 llvm::createLinearScanRegisterAllocator); 178 179 llvm::CodeGenOpt::Level OptLevel = llvm::CodeGenOpt::Default; 180 if (mCodeGenOpts.OptimizationLevel == 0) { 181 OptLevel = llvm::CodeGenOpt::None; 182 } else if (mCodeGenOpts.OptimizationLevel == 3) { 183 OptLevel = llvm::CodeGenOpt::Aggressive; 184 } 185 186 llvm::TargetMachine::CodeGenFileType CGFT = 187 llvm::TargetMachine::CGFT_AssemblyFile; 188 if (mOT == Slang::OT_Object) { 189 CGFT = llvm::TargetMachine::CGFT_ObjectFile; 190 } 191 if (TM->addPassesToEmitFile(*mCodeGenPasses, FormattedOutStream, 192 CGFT, OptLevel)) { 193 mDiagEngine.Report(clang::diag::err_fe_unable_to_interface_with_target); 194 return false; 195 } 196 197 return true; 198} 199 200Backend::Backend(clang::DiagnosticsEngine *DiagEngine, 201 const clang::CodeGenOptions &CodeGenOpts, 202 const clang::TargetOptions &TargetOpts, 203 PragmaList *Pragmas, 204 llvm::raw_ostream *OS, 205 Slang::OutputType OT) 206 : ASTConsumer(), 207 mTargetOpts(TargetOpts), 208 mpModule(NULL), 209 mpOS(OS), 210 mOT(OT), 211 mGen(NULL), 212 mPerFunctionPasses(NULL), 213 mPerModulePasses(NULL), 214 mCodeGenPasses(NULL), 215 mLLVMContext(llvm::getGlobalContext()), 216 mDiagEngine(*DiagEngine), 217 mCodeGenOpts(CodeGenOpts), 218 mPragmas(Pragmas) { 219 FormattedOutStream.setStream(*mpOS, 220 llvm::formatted_raw_ostream::PRESERVE_STREAM); 221 mGen = CreateLLVMCodeGen(mDiagEngine, "", mCodeGenOpts, mLLVMContext); 222 return; 223} 224 225void Backend::Initialize(clang::ASTContext &Ctx) { 226 mGen->Initialize(Ctx); 227 228 mpModule = mGen->GetModule(); 229 230 return; 231} 232 233// Encase the Bitcode in a wrapper containing RS version information. 234void Backend::WrapBitcode(llvm::raw_string_ostream &Bitcode) { 235 struct bcinfo::BCWrapperHeader header; 236 header.Magic = 0x0B17C0DE; 237 header.Version = 0; 238 header.BitcodeOffset = sizeof(header); 239 header.BitcodeSize = Bitcode.str().length(); 240 header.HeaderVersion = 0; 241 header.TargetAPI = getTargetAPI(); 242 243 // Write out the bitcode wrapper. 244 FormattedOutStream.write((const char*) &header, sizeof(header)); 245 246 // Write out the actual encoded bitcode. 247 FormattedOutStream << Bitcode.str(); 248 return; 249} 250 251void Backend::HandleTopLevelDecl(clang::DeclGroupRef D) { 252 mGen->HandleTopLevelDecl(D); 253 return; 254} 255 256void Backend::HandleTranslationUnit(clang::ASTContext &Ctx) { 257 HandleTranslationUnitPre(Ctx); 258 259 mGen->HandleTranslationUnit(Ctx); 260 261 // Here, we complete a translation unit (whole translation unit is now in LLVM 262 // IR). Now, interact with LLVM backend to generate actual machine code (asm 263 // or machine code, whatever.) 264 265 // Silently ignore if we weren't initialized for some reason. 266 if (!mpModule) 267 return; 268 269 llvm::Module *M = mGen->ReleaseModule(); 270 if (!M) { 271 // The module has been released by IR gen on failures, do not double free. 272 mpModule = NULL; 273 return; 274 } 275 276 slangAssert(mpModule == M && 277 "Unexpected module change during LLVM IR generation"); 278 279 // Insert #pragma information into metadata section of module 280 if (!mPragmas->empty()) { 281 llvm::NamedMDNode *PragmaMetadata = 282 mpModule->getOrInsertNamedMetadata(Slang::PragmaMetadataName); 283 for (PragmaList::const_iterator I = mPragmas->begin(), E = mPragmas->end(); 284 I != E; 285 I++) { 286 llvm::SmallVector<llvm::Value*, 2> Pragma; 287 // Name goes first 288 Pragma.push_back(llvm::MDString::get(mLLVMContext, I->first)); 289 // And then value 290 Pragma.push_back(llvm::MDString::get(mLLVMContext, I->second)); 291 292 // Create MDNode and insert into PragmaMetadata 293 PragmaMetadata->addOperand( 294 llvm::MDNode::get(mLLVMContext, Pragma)); 295 } 296 } 297 298 HandleTranslationUnitPost(mpModule); 299 300 // Create passes for optimization and code emission 301 302 // Create and run per-function passes 303 CreateFunctionPasses(); 304 if (mPerFunctionPasses) { 305 mPerFunctionPasses->doInitialization(); 306 307 for (llvm::Module::iterator I = mpModule->begin(), E = mpModule->end(); 308 I != E; 309 I++) 310 if (!I->isDeclaration()) 311 mPerFunctionPasses->run(*I); 312 313 mPerFunctionPasses->doFinalization(); 314 } 315 316 // Create and run module passes 317 CreateModulePasses(); 318 if (mPerModulePasses) 319 mPerModulePasses->run(*mpModule); 320 321 switch (mOT) { 322 case Slang::OT_Assembly: 323 case Slang::OT_Object: { 324 if (!CreateCodeGenPasses()) 325 return; 326 327 mCodeGenPasses->doInitialization(); 328 329 for (llvm::Module::iterator I = mpModule->begin(), E = mpModule->end(); 330 I != E; 331 I++) 332 if (!I->isDeclaration()) 333 mCodeGenPasses->run(*I); 334 335 mCodeGenPasses->doFinalization(); 336 break; 337 } 338 case Slang::OT_LLVMAssembly: { 339 llvm::PassManager *LLEmitPM = new llvm::PassManager(); 340 LLEmitPM->add(llvm::createPrintModulePass(&FormattedOutStream)); 341 LLEmitPM->run(*mpModule); 342 break; 343 } 344 case Slang::OT_Bitcode: { 345 llvm::PassManager *BCEmitPM = new llvm::PassManager(); 346 std::string BCStr; 347 llvm::raw_string_ostream Bitcode(BCStr); 348 if (getTargetAPI() < SLANG_ICS_TARGET_API) { 349 // Pre-ICS targets must use the LLVM 2.9 BitcodeWriter 350 BCEmitPM->add(llvm_2_9::createBitcodeWriterPass(Bitcode)); 351 } else { 352 BCEmitPM->add(llvm::createBitcodeWriterPass(Bitcode)); 353 } 354 355 BCEmitPM->run(*mpModule); 356 WrapBitcode(Bitcode); 357 break; 358 } 359 case Slang::OT_Nothing: { 360 return; 361 } 362 default: { 363 slangAssert(false && "Unknown output type"); 364 } 365 } 366 367 FormattedOutStream.flush(); 368 369 return; 370} 371 372void Backend::HandleTagDeclDefinition(clang::TagDecl *D) { 373 mGen->HandleTagDeclDefinition(D); 374 return; 375} 376 377void Backend::CompleteTentativeDefinition(clang::VarDecl *D) { 378 mGen->CompleteTentativeDefinition(D); 379 return; 380} 381 382Backend::~Backend() { 383 delete mpModule; 384 delete mGen; 385 delete mPerFunctionPasses; 386 delete mPerModulePasses; 387 delete mCodeGenPasses; 388 return; 389} 390 391} // namespace slang 392