slang_backend.cpp revision 462aefd62cc646d2ff753c1d003ef3cd7bbea26
1#include "slang.hpp" 2#include "slang_backend.hpp" 3 4#include "llvm/Module.h" /* for class llvm::Module */ 5#include "llvm/Metadata.h" /* for class llvm::NamedMDNode */ 6#include "llvm/LLVMContext.h" /* for llvm::getGlobalContext() */ 7 8#include "llvm/Target/TargetMachine.h" /* for class llvm::TargetMachine and llvm::TargetMachine::AssemblyFile */ 9#include "llvm/Target/TargetOptions.h" /* for 10 * variable bool llvm::UseSoftFloat 11 * FloatABI::ABIType llvm::FloatABIType 12 * bool llvm::NoZerosInBSS 13 */ 14#include "llvm/Target/TargetRegistry.h" /* for class llvm::TargetRegistry */ 15#include "llvm/Target/SubtargetFeature.h" /* for class llvm::SubtargetFeature */ 16 17#include "llvm/CodeGen/RegAllocRegistry.h" /* for class llvm::RegisterRegAlloc */ 18#include "llvm/CodeGen/SchedulerRegistry.h" /* for class llvm::RegisterScheduler and llvm::createDefaultScheduler() */ 19 20#include "llvm/Assembly/PrintModulePass.h" /* for function createPrintModulePass() */ 21#include "llvm/Bitcode/ReaderWriter.h" /* for function createBitcodeWriterPass() */ 22 23#include "clang/AST/Decl.h" /* for class clang::*Decl */ 24#include "clang/AST/Stmt.h" /* for class clang::*Stmt */ 25#include "clang/AST/StmtVisitor.h" /* for class clang::StmtVisitor */ 26#include "clang/AST/Expr.h" /* for class clang::*Expr */ 27#include "clang/AST/DeclGroup.h" /* for class clang::DeclGroupRef */ 28#include "clang/AST/ASTContext.h" /* for class clang::ASTContext */ 29 30#include "clang/Basic/TargetInfo.h" /* for class clang::TargetInfo */ 31#include "clang/Basic/Diagnostic.h" /* for class clang::Diagnostic */ 32#include "clang/Basic/TargetOptions.h" /* for class clang::TargetOptions */ 33 34#include "clang/Frontend/FrontendDiagnostic.h" /* for clang::diag::* */ 35 36#include "clang/CodeGen/ModuleBuilder.h" /* for class clang::CodeGenerator */ 37#include "clang/CodeGen/CodeGenOptions.h" /* for class clang::CodeGenOptions */ 38 39namespace { 40 using namespace clang; 41 42 class CheckFunctionCallVisitor : public StmtVisitor<CheckFunctionCallVisitor> { 43 private: 44 Diagnostic& mDiags; 45 SourceManager& mSourceMgr; 46 47 public: 48 CheckFunctionCallVisitor(Diagnostic& Diags, SourceManager& SourceMgr) : 49 mDiags(Diags), 50 mSourceMgr(SourceMgr) 51 { 52 return; 53 } 54 55 void VisitStmt(Stmt* S); 56 void VisitCallExpr(CallExpr* Node); 57 }; 58 59 void CheckFunctionCallVisitor::VisitStmt(Stmt* S) { 60 for(Stmt::child_iterator I = S->child_begin(); 61 I != S->child_end(); 62 I++) 63 if(*I) 64 Visit(*I); 65 return; 66 } 67 68 void CheckFunctionCallVisitor::VisitCallExpr(CallExpr* Node) { 69 if(Node != NULL) { 70 const FunctionDecl* Callee = Node->getDirectCallee(); 71 if(Callee != NULL) { 72 if(!Callee->getBody() && !Callee->hasPrototype()) { 73 /* Warn: Function has neither definition nore prototype */ 74 mDiags.Report(FullSourceLoc(Node->getLocStart(), mSourceMgr), 75 mDiags.getCustomDiagID(Diagnostic::Warning, "no previous prototype for function '%0'")) << Callee->getName(); 76 } 77 } 78 } 79 return; 80 } 81} 82 83namespace slang { 84 85bool Backend::CreateCodeGenPasses() { 86 if(mOutputType != SlangCompilerOutput_Assembly && mOutputType != SlangCompilerOutput_Obj) 87 return true; 88 89 /* Now we add passes for code emitting */ 90 if(mCodeGenPasses) { 91 return true; 92 } else { 93 mCodeGenPasses = new llvm::FunctionPassManager(mpModule); 94 mCodeGenPasses->add(new llvm::TargetData(*mpTargetData)); 95 } 96 97 /* Create the TargetMachine for generating code. */ 98 std::string Triple = mpModule->getTargetTriple(); 99 100 std::string Error; 101 const llvm::Target* TargetInfo = llvm::TargetRegistry::lookupTarget(Triple, Error); 102 if(TargetInfo == NULL) { 103 mDiags.Report(clang::diag::err_fe_unable_to_create_target) << Error; 104 return false; 105 } 106 107 llvm::NoFramePointerElim = mCodeGenOpts.DisableFPElim; 108 109 /* 110 * Use hardware FPU. 111 * 112 * FIXME: Need to detect the CPU capability and decide whether to use softfp. To use softfp, change following 2 lines to 113 * 114 * llvm::FloatABIType = llvm::FloatABI::Soft; 115 * llvm::UseSoftFloat = true; 116 */ 117 llvm::FloatABIType = llvm::FloatABI::Hard; 118 llvm::UseSoftFloat = false; 119 120 llvm::TargetMachine::setRelocationModel(llvm::Reloc::Static); /* ACC needs all unknown symbols resolved at compilation time. 121 So we don't need any relocation model. */ 122 123 /* The target with pointer size greater than 32 (e.g. x86_64 architecture) may need large data address model */ 124 if(mpTargetData->getPointerSizeInBits() > 32) 125 llvm::TargetMachine::setCodeModel(llvm::CodeModel::Medium); 126 else 127 llvm::TargetMachine::setCodeModel(llvm::CodeModel::Small); /* This is set for the linker (specify how large of the virtual addresses 128 we can access for all unknown symbols.) */ 129 130 /* setup feature string */ 131 std::string FeaturesStr; 132 if(mTargetOpts.CPU.size() || mTargetOpts.Features.size()) { 133 llvm::SubtargetFeatures Features; 134 135 Features.setCPU(mTargetOpts.CPU); 136 137 for(std::vector<std::string>::const_iterator it = mTargetOpts.Features.begin(); 138 it != mTargetOpts.Features.end(); 139 it++) 140 Features.AddFeature(*it); 141 142 FeaturesStr = Features.getString(); 143 } 144 llvm::TargetMachine *TM = TargetInfo->createTargetMachine(Triple, FeaturesStr); 145 146 /* Register scheduler */ 147 llvm::RegisterScheduler::setDefault(llvm::createDefaultScheduler); 148 149 /* Register allocation policy: 150 * createLocalRegisterAllocator: fast but bad quality 151 * createLinearScanRegisterAllocator: not so fast but good quality 152 */ 153 llvm::RegisterRegAlloc::setDefault((mCodeGenOpts.OptimizationLevel == 0) ? llvm::createLocalRegisterAllocator : llvm::createLinearScanRegisterAllocator); 154 155 llvm::CodeGenOpt::Level OptLevel = llvm::CodeGenOpt::Default; 156 if(mCodeGenOpts.OptimizationLevel == 0) 157 OptLevel = llvm::CodeGenOpt::None; 158 else if(mCodeGenOpts.OptimizationLevel == 3) 159 OptLevel = llvm::CodeGenOpt::Aggressive; 160 161 llvm::TargetMachine::CodeGenFileType CGFT = llvm::TargetMachine::CGFT_AssemblyFile;; 162 if(mOutputType == SlangCompilerOutput_Obj) 163 CGFT = llvm::TargetMachine::CGFT_ObjectFile; 164 if(TM->addPassesToEmitFile(*mCodeGenPasses, FormattedOutStream, CGFT, OptLevel)) { 165 mDiags.Report(clang::diag::err_fe_unable_to_interface_with_target); 166 return false; 167 } 168 169 return true; 170} 171 172Backend::Backend(Diagnostic &Diags, 173 const CodeGenOptions& CodeGenOpts, 174 const TargetOptions& TargetOpts, 175 const PragmaList& Pragmas, 176 llvm::raw_ostream* OS, 177 SlangCompilerOutputTy OutputType) : 178 ASTConsumer(), 179 mLLVMContext(llvm::getGlobalContext()), 180 mDiags(Diags), 181 mCodeGenOpts(CodeGenOpts), 182 mTargetOpts(TargetOpts), 183 mPragmas(Pragmas), 184 mpOS(OS), 185 mOutputType(OutputType), 186 mpModule(NULL), 187 mpTargetData(NULL), 188 mGen(NULL), 189 mPerFunctionPasses(NULL), 190 mPerModulePasses(NULL), 191 mCodeGenPasses(NULL) 192{ 193 FormattedOutStream.setStream(*mpOS, llvm::formatted_raw_ostream::PRESERVE_STREAM); 194 mGen = CreateLLVMCodeGen(mDiags, "", mCodeGenOpts, mLLVMContext); 195 return; 196} 197 198void Backend::Initialize(ASTContext &Ctx) { 199 mGen->Initialize(Ctx); 200 201 mpModule = mGen->GetModule(); 202 mpTargetData = new llvm::TargetData(Slang::TargetDescription); 203 204 return; 205} 206 207void Backend::HandleTopLevelDecl(DeclGroupRef D) { 208 mGen->HandleTopLevelDecl(D); 209 return; 210} 211 212void Backend::HandleTranslationUnit(ASTContext& Ctx) { 213 /* Warn if there's any function without prototype declaration or function definition called */ 214 TranslationUnitDecl* TUDecl = Ctx.getTranslationUnitDecl(); 215 for(DeclContext::decl_iterator DI = TUDecl->decls_begin(); 216 DI != TUDecl->decls_end(); 217 DI++) 218 { 219 if(DI->getKind() == Decl::Function) { 220 FunctionDecl* FD = static_cast<FunctionDecl*>(*DI); 221 Stmt* Body = FD->getBody(); 222 if(Body != NULL) { 223 CheckFunctionCallVisitor FunctionCallChecker(mDiags, Ctx.getSourceManager()); 224 FunctionCallChecker.Visit(Body); 225 } 226 } 227 } 228 229 mGen->HandleTranslationUnit(Ctx); 230 231 /* 232 * Here, we complete a translation unit (whole translation unit is now in LLVM IR). 233 * Now, interact with LLVM backend to generate actual machine code (asm or machine 234 * code, whatever.) 235 */ 236 237 if(!mpModule || !mpTargetData) /* Silently ignore if we weren't initialized for some reason. */ 238 return; 239 240 llvm::Module* M = mGen->ReleaseModule(); 241 if(!M) { 242 /* The module has been released by IR gen on failures, do not double free. */ 243 mpModule = NULL; 244 return; 245 } 246 247 assert(mpModule == M && "Unexpected module change during LLVM IR generation"); 248 249 /* Insert #pragma information into metadata section of module */ 250 if(!mPragmas.empty()) { 251 llvm::NamedMDNode* PragmaMetadata = llvm::NamedMDNode::Create(mLLVMContext, Slang::PragmaMetadataName, NULL, 0, mpModule); 252 for(PragmaList::const_iterator it = mPragmas.begin(); 253 it != mPragmas.end(); 254 it++) 255 { 256 llvm::SmallVector<llvm::Value*, 2> Pragma; 257 /* Name goes first */ 258 Pragma.push_back(llvm::MDString::get(mLLVMContext, it->first)); 259 /* And then value */ 260 Pragma.push_back(llvm::MDString::get(mLLVMContext, it->second)); 261 /* Create MDNode and insert into PragmaMetadata */ 262 PragmaMetadata->addOperand( llvm::MDNode::get(mLLVMContext, Pragma.data(), Pragma.size()) ); 263 } 264 } 265 266 HandleTranslationUnitEx(Ctx); 267 268 /* Create passes for optimization and code emission */ 269 270 /* Create and run per-function passes */ 271 CreateFunctionPasses(); 272 if(mPerFunctionPasses) { 273 mPerFunctionPasses->doInitialization(); 274 275 for(llvm::Module::iterator I = mpModule->begin(); 276 I != mpModule->end(); 277 I++) 278 if(!I->isDeclaration()) 279 mPerFunctionPasses->run(*I); 280 281 mPerFunctionPasses->doFinalization(); 282 } 283 284 285 /* Create and run module passes */ 286 CreateModulePasses(); 287 if(mPerModulePasses) 288 mPerModulePasses->run(*mpModule); 289 290 switch(mOutputType) { 291 case SlangCompilerOutput_Assembly: 292 case SlangCompilerOutput_Obj: 293 if(!CreateCodeGenPasses()) 294 return; 295 296 mCodeGenPasses->doInitialization(); 297 298 for(llvm::Module::iterator I = mpModule->begin(); 299 I != mpModule->end(); 300 I++) 301 if(!I->isDeclaration()) 302 mCodeGenPasses->run(*I); 303 304 mCodeGenPasses->doFinalization(); 305 break; 306 307 case SlangCompilerOutput_LL: 308 { 309 llvm::PassManager* LLEmitPM = new llvm::PassManager(); 310 LLEmitPM->add(llvm::createPrintModulePass(&FormattedOutStream)); 311 LLEmitPM->run(*mpModule); 312 } 313 break; 314 315 case SlangCompilerOutput_Bitcode: 316 { 317 llvm::PassManager* BCEmitPM = new llvm::PassManager(); 318 BCEmitPM->add(llvm::createBitcodeWriterPass(FormattedOutStream)); 319 BCEmitPM->run(*mpModule); 320 } 321 break; 322 323 case SlangCompilerOutput_Nothing: 324 return; 325 break; 326 327 default: 328 assert(false && "Unknown output type"); 329 break; 330 } 331 332 FormattedOutStream.flush(); 333 334 return; 335} 336 337void Backend::HandleTagDeclDefinition(TagDecl* D) { 338 mGen->HandleTagDeclDefinition(D); 339 return; 340} 341 342void Backend::CompleteTentativeDefinition(VarDecl* D) { 343 mGen->CompleteTentativeDefinition(D); 344 return; 345} 346 347Backend::~Backend() { 348 if(mpModule) 349 delete mpModule; 350 if(mpTargetData) 351 delete mpTargetData; 352 if(mGen) 353 delete mGen; 354 if(mPerFunctionPasses) 355 delete mPerFunctionPasses; 356 if(mPerModulePasses) 357 delete mPerModulePasses; 358 if(mCodeGenPasses) 359 delete mCodeGenPasses; 360 return; 361} 362 363} /* namespace slang */ 364