LLVM API Documentation
00001 //===-- Writer.cpp - Library for converting LLVM code to C ----------------===// 00002 // 00003 // The LLVM Compiler Infrastructure 00004 // 00005 // This file was developed by the LLVM research group and is distributed under 00006 // the University of Illinois Open Source License. See LICENSE.TXT for details. 00007 // 00008 //===----------------------------------------------------------------------===// 00009 // 00010 // This library converts LLVM code to C code, compilable by GCC and other C 00011 // compilers. 00012 // 00013 //===----------------------------------------------------------------------===// 00014 00015 #include "CTargetMachine.h" 00016 #include "llvm/CallingConv.h" 00017 #include "llvm/Constants.h" 00018 #include "llvm/DerivedTypes.h" 00019 #include "llvm/Module.h" 00020 #include "llvm/Instructions.h" 00021 #include "llvm/Pass.h" 00022 #include "llvm/PassManager.h" 00023 #include "llvm/SymbolTable.h" 00024 #include "llvm/Intrinsics.h" 00025 #include "llvm/IntrinsicInst.h" 00026 #include "llvm/Analysis/ConstantsScanner.h" 00027 #include "llvm/Analysis/FindUsedTypes.h" 00028 #include "llvm/Analysis/LoopInfo.h" 00029 #include "llvm/CodeGen/IntrinsicLowering.h" 00030 #include "llvm/Transforms/Scalar.h" 00031 #include "llvm/Target/TargetMachineRegistry.h" 00032 #include "llvm/Support/CallSite.h" 00033 #include "llvm/Support/CFG.h" 00034 #include "llvm/Support/GetElementPtrTypeIterator.h" 00035 #include "llvm/Support/InstVisitor.h" 00036 #include "llvm/Support/Mangler.h" 00037 #include "llvm/Support/MathExtras.h" 00038 #include "llvm/ADT/StringExtras.h" 00039 #include "llvm/ADT/STLExtras.h" 00040 #include "llvm/Support/MathExtras.h" 00041 #include "llvm/Config/config.h" 00042 #include <algorithm> 00043 #include <iostream> 00044 #include <ios> 00045 #include <sstream> 00046 using namespace llvm; 00047 00048 namespace { 00049 // Register the target. 00050 RegisterTarget<CTargetMachine> X("c", " C backend"); 00051 00052 /// CBackendNameAllUsedStructsAndMergeFunctions - This pass inserts names for 00053 /// any unnamed structure types that are used by the program, and merges 00054 /// external functions with the same name. 00055 /// 00056 class CBackendNameAllUsedStructsAndMergeFunctions : public ModulePass { 00057 void getAnalysisUsage(AnalysisUsage &AU) const { 00058 AU.addRequired<FindUsedTypes>(); 00059 } 00060 00061 virtual const char *getPassName() const { 00062 return "C backend type canonicalizer"; 00063 } 00064 00065 virtual bool runOnModule(Module &M); 00066 }; 00067 00068 /// CWriter - This class is the main chunk of code that converts an LLVM 00069 /// module to a C translation unit. 00070 class CWriter : public FunctionPass, public InstVisitor<CWriter> { 00071 std::ostream &Out; 00072 DefaultIntrinsicLowering IL; 00073 Mangler *Mang; 00074 LoopInfo *LI; 00075 const Module *TheModule; 00076 std::map<const Type *, std::string> TypeNames; 00077 00078 std::map<const ConstantFP *, unsigned> FPConstantMap; 00079 public: 00080 CWriter(std::ostream &o) : Out(o) {} 00081 00082 virtual const char *getPassName() const { return "C backend"; } 00083 00084 void getAnalysisUsage(AnalysisUsage &AU) const { 00085 AU.addRequired<LoopInfo>(); 00086 AU.setPreservesAll(); 00087 } 00088 00089 virtual bool doInitialization(Module &M); 00090 00091 bool runOnFunction(Function &F) { 00092 LI = &getAnalysis<LoopInfo>(); 00093 00094 // Get rid of intrinsics we can't handle. 00095 lowerIntrinsics(F); 00096 00097 // Output all floating point constants that cannot be printed accurately. 00098 printFloatingPointConstants(F); 00099 00100 // Ensure that no local symbols conflict with global symbols. 00101 F.renameLocalSymbols(); 00102 00103 printFunction(F); 00104 FPConstantMap.clear(); 00105 return false; 00106 } 00107 00108 virtual bool doFinalization(Module &M) { 00109 // Free memory... 00110 delete Mang; 00111 TypeNames.clear(); 00112 return false; 00113 } 00114 00115 std::ostream &printType(std::ostream &Out, const Type *Ty, 00116 const std::string &VariableName = "", 00117 bool IgnoreName = false); 00118 00119 void printStructReturnPointerFunctionType(std::ostream &Out, 00120 const PointerType *Ty); 00121 00122 void writeOperand(Value *Operand); 00123 void writeOperandInternal(Value *Operand); 00124 00125 private : 00126 void lowerIntrinsics(Function &F); 00127 00128 void printModule(Module *M); 00129 void printModuleTypes(const SymbolTable &ST); 00130 void printContainedStructs(const Type *Ty, std::set<const StructType *> &); 00131 void printFloatingPointConstants(Function &F); 00132 void printFunctionSignature(const Function *F, bool Prototype); 00133 00134 void printFunction(Function &); 00135 void printBasicBlock(BasicBlock *BB); 00136 void printLoop(Loop *L); 00137 00138 void printConstant(Constant *CPV); 00139 void printConstantArray(ConstantArray *CPA); 00140 void printConstantPacked(ConstantPacked *CP); 00141 00142 // isInlinableInst - Attempt to inline instructions into their uses to build 00143 // trees as much as possible. To do this, we have to consistently decide 00144 // what is acceptable to inline, so that variable declarations don't get 00145 // printed and an extra copy of the expr is not emitted. 00146 // 00147 static bool isInlinableInst(const Instruction &I) { 00148 // Always inline setcc instructions, even if they are shared by multiple 00149 // expressions. GCC generates horrible code if we don't. 00150 if (isa<SetCondInst>(I)) return true; 00151 00152 // Must be an expression, must be used exactly once. If it is dead, we 00153 // emit it inline where it would go. 00154 if (I.getType() == Type::VoidTy || !I.hasOneUse() || 00155 isa<TerminatorInst>(I) || isa<CallInst>(I) || isa<PHINode>(I) || 00156 isa<LoadInst>(I) || isa<VAArgInst>(I)) 00157 // Don't inline a load across a store or other bad things! 00158 return false; 00159 00160 // Only inline instruction it it's use is in the same BB as the inst. 00161 return I.getParent() == cast<Instruction>(I.use_back())->getParent(); 00162 } 00163 00164 // isDirectAlloca - Define fixed sized allocas in the entry block as direct 00165 // variables which are accessed with the & operator. This causes GCC to 00166 // generate significantly better code than to emit alloca calls directly. 00167 // 00168 static const AllocaInst *isDirectAlloca(const Value *V) { 00169 const AllocaInst *AI = dyn_cast<AllocaInst>(V); 00170 if (!AI) return false; 00171 if (AI->isArrayAllocation()) 00172 return 0; // FIXME: we can also inline fixed size array allocas! 00173 if (AI->getParent() != &AI->getParent()->getParent()->getEntryBlock()) 00174 return 0; 00175 return AI; 00176 } 00177 00178 // Instruction visitation functions 00179 friend class InstVisitor<CWriter>; 00180 00181 void visitReturnInst(ReturnInst &I); 00182 void visitBranchInst(BranchInst &I); 00183 void visitSwitchInst(SwitchInst &I); 00184 void visitInvokeInst(InvokeInst &I) { 00185 assert(0 && "Lowerinvoke pass didn't work!"); 00186 } 00187 00188 void visitUnwindInst(UnwindInst &I) { 00189 assert(0 && "Lowerinvoke pass didn't work!"); 00190 } 00191 void visitUnreachableInst(UnreachableInst &I); 00192 00193 void visitPHINode(PHINode &I); 00194 void visitBinaryOperator(Instruction &I); 00195 00196 void visitCastInst (CastInst &I); 00197 void visitSelectInst(SelectInst &I); 00198 void visitCallInst (CallInst &I); 00199 void visitShiftInst(ShiftInst &I) { visitBinaryOperator(I); } 00200 00201 void visitMallocInst(MallocInst &I); 00202 void visitAllocaInst(AllocaInst &I); 00203 void visitFreeInst (FreeInst &I); 00204 void visitLoadInst (LoadInst &I); 00205 void visitStoreInst (StoreInst &I); 00206 void visitGetElementPtrInst(GetElementPtrInst &I); 00207 void visitVAArgInst (VAArgInst &I); 00208 00209 void visitInstruction(Instruction &I) { 00210 std::cerr << "C Writer does not know about " << I; 00211 abort(); 00212 } 00213 00214 void outputLValue(Instruction *I) { 00215 Out << " " << Mang->getValueName(I) << " = "; 00216 } 00217 00218 bool isGotoCodeNecessary(BasicBlock *From, BasicBlock *To); 00219 void printPHICopiesForSuccessor(BasicBlock *CurBlock, 00220 BasicBlock *Successor, unsigned Indent); 00221 void printBranchToBlock(BasicBlock *CurBlock, BasicBlock *SuccBlock, 00222 unsigned Indent); 00223 void printIndexingExpression(Value *Ptr, gep_type_iterator I, 00224 gep_type_iterator E); 00225 }; 00226 } 00227 00228 /// This method inserts names for any unnamed structure types that are used by 00229 /// the program, and removes names from structure types that are not used by the 00230 /// program. 00231 /// 00232 bool CBackendNameAllUsedStructsAndMergeFunctions::runOnModule(Module &M) { 00233 // Get a set of types that are used by the program... 00234 std::set<const Type *> UT = getAnalysis<FindUsedTypes>().getTypes(); 00235 00236 // Loop over the module symbol table, removing types from UT that are 00237 // already named, and removing names for types that are not used. 00238 // 00239 SymbolTable &MST = M.getSymbolTable(); 00240 for (SymbolTable::type_iterator TI = MST.type_begin(), TE = MST.type_end(); 00241 TI != TE; ) { 00242 SymbolTable::type_iterator I = TI++; 00243 00244 // If this is not used, remove it from the symbol table. 00245 std::set<const Type *>::iterator UTI = UT.find(I->second); 00246 if (UTI == UT.end()) 00247 MST.remove(I); 00248 else 00249 UT.erase(UTI); // Only keep one name for this type. 00250 } 00251 00252 // UT now contains types that are not named. Loop over it, naming 00253 // structure types. 00254 // 00255 bool Changed = false; 00256 unsigned RenameCounter = 0; 00257 for (std::set<const Type *>::const_iterator I = UT.begin(), E = UT.end(); 00258 I != E; ++I) 00259 if (const StructType *ST = dyn_cast<StructType>(*I)) { 00260 while (M.addTypeName("unnamed"+utostr(RenameCounter), ST)) 00261 ++RenameCounter; 00262 Changed = true; 00263 } 00264 00265 00266 // Loop over all external functions and globals. If we have two with 00267 // identical names, merge them. 00268 // FIXME: This code should disappear when we don't allow values with the same 00269 // names when they have different types! 00270 std::map<std::string, GlobalValue*> ExtSymbols; 00271 for (Module::iterator I = M.begin(), E = M.end(); I != E;) { 00272 Function *GV = I++; 00273 if (GV->isExternal() && GV->hasName()) { 00274 std::pair<std::map<std::string, GlobalValue*>::iterator, bool> X 00275 = ExtSymbols.insert(std::make_pair(GV->getName(), GV)); 00276 if (!X.second) { 00277 // Found a conflict, replace this global with the previous one. 00278 GlobalValue *OldGV = X.first->second; 00279 GV->replaceAllUsesWith(ConstantExpr::getCast(OldGV, GV->getType())); 00280 GV->eraseFromParent(); 00281 Changed = true; 00282 } 00283 } 00284 } 00285 // Do the same for globals. 00286 for (Module::global_iterator I = M.global_begin(), E = M.global_end(); 00287 I != E;) { 00288 GlobalVariable *GV = I++; 00289 if (GV->isExternal() && GV->hasName()) { 00290 std::pair<std::map<std::string, GlobalValue*>::iterator, bool> X 00291 = ExtSymbols.insert(std::make_pair(GV->getName(), GV)); 00292 if (!X.second) { 00293 // Found a conflict, replace this global with the previous one. 00294 GlobalValue *OldGV = X.first->second; 00295 GV->replaceAllUsesWith(ConstantExpr::getCast(OldGV, GV->getType())); 00296 GV->eraseFromParent(); 00297 Changed = true; 00298 } 00299 } 00300 } 00301 00302 return Changed; 00303 } 00304 00305 /// printStructReturnPointerFunctionType - This is like printType for a struct 00306 /// return type, except, instead of printing the type as void (*)(Struct*, ...) 00307 /// print it as "Struct (*)(...)", for struct return functions. 00308 void CWriter::printStructReturnPointerFunctionType(std::ostream &Out, 00309 const PointerType *TheTy) { 00310 const FunctionType *FTy = cast<FunctionType>(TheTy->getElementType()); 00311 std::stringstream FunctionInnards; 00312 FunctionInnards << " (*) ("; 00313 bool PrintedType = false; 00314 00315 FunctionType::param_iterator I = FTy->param_begin(), E = FTy->param_end(); 00316 const Type *RetTy = cast<PointerType>(I->get())->getElementType(); 00317 for (++I; I != E; ++I) { 00318 if (PrintedType) 00319 FunctionInnards << ", "; 00320 printType(FunctionInnards, *I, ""); 00321 PrintedType = true; 00322 } 00323 if (FTy->isVarArg()) { 00324 if (PrintedType) 00325 FunctionInnards << ", ..."; 00326 } else if (!PrintedType) { 00327 FunctionInnards << "void"; 00328 } 00329 FunctionInnards << ')'; 00330 std::string tstr = FunctionInnards.str(); 00331 printType(Out, RetTy, tstr); 00332 } 00333 00334 00335 // Pass the Type* and the variable name and this prints out the variable 00336 // declaration. 00337 // 00338 std::ostream &CWriter::printType(std::ostream &Out, const Type *Ty, 00339 const std::string &NameSoFar, 00340 bool IgnoreName) { 00341 if (Ty->isPrimitiveType()) 00342 switch (Ty->getTypeID()) { 00343 case Type::VoidTyID: return Out << "void " << NameSoFar; 00344 case Type::BoolTyID: return Out << "bool " << NameSoFar; 00345 case Type::UByteTyID: return Out << "unsigned char " << NameSoFar; 00346 case Type::SByteTyID: return Out << "signed char " << NameSoFar; 00347 case Type::UShortTyID: return Out << "unsigned short " << NameSoFar; 00348 case Type::ShortTyID: return Out << "short " << NameSoFar; 00349 case Type::UIntTyID: return Out << "unsigned " << NameSoFar; 00350 case Type::IntTyID: return Out << "int " << NameSoFar; 00351 case Type::ULongTyID: return Out << "unsigned long long " << NameSoFar; 00352 case Type::LongTyID: return Out << "signed long long " << NameSoFar; 00353 case Type::FloatTyID: return Out << "float " << NameSoFar; 00354 case Type::DoubleTyID: return Out << "double " << NameSoFar; 00355 default : 00356 std::cerr << "Unknown primitive type: " << *Ty << "\n"; 00357 abort(); 00358 } 00359 00360 // Check to see if the type is named. 00361 if (!IgnoreName || isa<OpaqueType>(Ty)) { 00362 std::map<const Type *, std::string>::iterator I = TypeNames.find(Ty); 00363 if (I != TypeNames.end()) return Out << I->second << ' ' << NameSoFar; 00364 } 00365 00366 switch (Ty->getTypeID()) { 00367 case Type::FunctionTyID: { 00368 const FunctionType *FTy = cast<FunctionType>(Ty); 00369 std::stringstream FunctionInnards; 00370 FunctionInnards << " (" << NameSoFar << ") ("; 00371 for (FunctionType::param_iterator I = FTy->param_begin(), 00372 E = FTy->param_end(); I != E; ++I) { 00373 if (I != FTy->param_begin()) 00374 FunctionInnards << ", "; 00375 printType(FunctionInnards, *I, ""); 00376 } 00377 if (FTy->isVarArg()) { 00378 if (FTy->getNumParams()) 00379 FunctionInnards << ", ..."; 00380 } else if (!FTy->getNumParams()) { 00381 FunctionInnards << "void"; 00382 } 00383 FunctionInnards << ')'; 00384 std::string tstr = FunctionInnards.str(); 00385 printType(Out, FTy->getReturnType(), tstr); 00386 return Out; 00387 } 00388 case Type::StructTyID: { 00389 const StructType *STy = cast<StructType>(Ty); 00390 Out << NameSoFar + " {\n"; 00391 unsigned Idx = 0; 00392 for (StructType::element_iterator I = STy->element_begin(), 00393 E = STy->element_end(); I != E; ++I) { 00394 Out << " "; 00395 printType(Out, *I, "field" + utostr(Idx++)); 00396 Out << ";\n"; 00397 } 00398 return Out << '}'; 00399 } 00400 00401 case Type::PointerTyID: { 00402 const PointerType *PTy = cast<PointerType>(Ty); 00403 std::string ptrName = "*" + NameSoFar; 00404 00405 if (isa<ArrayType>(PTy->getElementType()) || 00406 isa<PackedType>(PTy->getElementType())) 00407 ptrName = "(" + ptrName + ")"; 00408 00409 return printType(Out, PTy->getElementType(), ptrName); 00410 } 00411 00412 case Type::ArrayTyID: { 00413 const ArrayType *ATy = cast<ArrayType>(Ty); 00414 unsigned NumElements = ATy->getNumElements(); 00415 if (NumElements == 0) NumElements = 1; 00416 return printType(Out, ATy->getElementType(), 00417 NameSoFar + "[" + utostr(NumElements) + "]"); 00418 } 00419 00420 case Type::PackedTyID: { 00421 const PackedType *PTy = cast<PackedType>(Ty); 00422 unsigned NumElements = PTy->getNumElements(); 00423 if (NumElements == 0) NumElements = 1; 00424 return printType(Out, PTy->getElementType(), 00425 NameSoFar + "[" + utostr(NumElements) + "]"); 00426 } 00427 00428 case Type::OpaqueTyID: { 00429 static int Count = 0; 00430 std::string TyName = "struct opaque_" + itostr(Count++); 00431 assert(TypeNames.find(Ty) == TypeNames.end()); 00432 TypeNames[Ty] = TyName; 00433 return Out << TyName << ' ' << NameSoFar; 00434 } 00435 default: 00436 assert(0 && "Unhandled case in getTypeProps!"); 00437 abort(); 00438 } 00439 00440 return Out; 00441 } 00442 00443 void CWriter::printConstantArray(ConstantArray *CPA) { 00444 00445 // As a special case, print the array as a string if it is an array of 00446 // ubytes or an array of sbytes with positive values. 00447 // 00448 const Type *ETy = CPA->getType()->getElementType(); 00449 bool isString = (ETy == Type::SByteTy || ETy == Type::UByteTy); 00450 00451 // Make sure the last character is a null char, as automatically added by C 00452 if (isString && (CPA->getNumOperands() == 0 || 00453 !cast<Constant>(*(CPA->op_end()-1))->isNullValue())) 00454 isString = false; 00455 00456 if (isString) { 00457 Out << '\"'; 00458 // Keep track of whether the last number was a hexadecimal escape 00459 bool LastWasHex = false; 00460 00461 // Do not include the last character, which we know is null 00462 for (unsigned i = 0, e = CPA->getNumOperands()-1; i != e; ++i) { 00463 unsigned char C = cast<ConstantInt>(CPA->getOperand(i))->getRawValue(); 00464 00465 // Print it out literally if it is a printable character. The only thing 00466 // to be careful about is when the last letter output was a hex escape 00467 // code, in which case we have to be careful not to print out hex digits 00468 // explicitly (the C compiler thinks it is a continuation of the previous 00469 // character, sheesh...) 00470 // 00471 if (isprint(C) && (!LastWasHex || !isxdigit(C))) { 00472 LastWasHex = false; 00473 if (C == '"' || C == '\\') 00474 Out << "\\" << C; 00475 else 00476 Out << C; 00477 } else { 00478 LastWasHex = false; 00479 switch (C) { 00480 case '\n': Out << "\\n"; break; 00481 case '\t': Out << "\\t"; break; 00482 case '\r': Out << "\\r"; break; 00483 case '\v': Out << "\\v"; break; 00484 case '\a': Out << "\\a"; break; 00485 case '\"': Out << "\\\""; break; 00486 case '\'': Out << "\\\'"; break; 00487 default: 00488 Out << "\\x"; 00489 Out << (char)(( C/16 < 10) ? ( C/16 +'0') : ( C/16 -10+'A')); 00490 Out << (char)(((C&15) < 10) ? ((C&15)+'0') : ((C&15)-10+'A')); 00491 LastWasHex = true; 00492 break; 00493 } 00494 } 00495 } 00496 Out << '\"'; 00497 } else { 00498 Out << '{'; 00499 if (CPA->getNumOperands()) { 00500 Out << ' '; 00501 printConstant(cast<Constant>(CPA->getOperand(0))); 00502 for (unsigned i = 1, e = CPA->getNumOperands(); i != e; ++i) { 00503 Out << ", "; 00504 printConstant(cast<Constant>(CPA->getOperand(i))); 00505 } 00506 } 00507 Out << " }"; 00508 } 00509 } 00510 00511 void CWriter::printConstantPacked(ConstantPacked *CP) { 00512 Out << '{'; 00513 if (CP->getNumOperands()) { 00514 Out << ' '; 00515 printConstant(cast<Constant>(CP->getOperand(0))); 00516 for (unsigned i = 1, e = CP->getNumOperands(); i != e; ++i) { 00517 Out << ", "; 00518 printConstant(cast<Constant>(CP->getOperand(i))); 00519 } 00520 } 00521 Out << " }"; 00522 } 00523 00524 // isFPCSafeToPrint - Returns true if we may assume that CFP may be written out 00525 // textually as a double (rather than as a reference to a stack-allocated 00526 // variable). We decide this by converting CFP to a string and back into a 00527 // double, and then checking whether the conversion results in a bit-equal 00528 // double to the original value of CFP. This depends on us and the target C 00529 // compiler agreeing on the conversion process (which is pretty likely since we 00530 // only deal in IEEE FP). 00531 // 00532 static bool isFPCSafeToPrint(const ConstantFP *CFP) { 00533 #if HAVE_PRINTF_A 00534 char Buffer[100]; 00535 sprintf(Buffer, "%a", CFP->getValue()); 00536 00537 if (!strncmp(Buffer, "0x", 2) || 00538 !strncmp(Buffer, "-0x", 3) || 00539 !strncmp(Buffer, "+0x", 3)) 00540 return atof(Buffer) == CFP->getValue(); 00541 return false; 00542 #else 00543 std::string StrVal = ftostr(CFP->getValue()); 00544 00545 while (StrVal[0] == ' ') 00546 StrVal.erase(StrVal.begin()); 00547 00548 // Check to make sure that the stringized number is not some string like "Inf" 00549 // or NaN. Check that the string matches the "[-+]?[0-9]" regex. 00550 if ((StrVal[0] >= '0' && StrVal[0] <= '9') || 00551 ((StrVal[0] == '-' || StrVal[0] == '+') && 00552 (StrVal[1] >= '0' && StrVal[1] <= '9'))) 00553 // Reparse stringized version! 00554 return atof(StrVal.c_str()) == CFP->getValue(); 00555 return false; 00556 #endif 00557 } 00558 00559 // printConstant - The LLVM Constant to C Constant converter. 00560 void CWriter::printConstant(Constant *CPV) { 00561 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CPV)) { 00562 switch (CE->getOpcode()) { 00563 case Instruction::Cast: 00564 Out << "(("; 00565 printType(Out, CPV->getType()); 00566 Out << ')'; 00567 printConstant(CE->getOperand(0)); 00568 Out << ')'; 00569 return; 00570 00571 case Instruction::GetElementPtr: 00572 Out << "(&("; 00573 printIndexingExpression(CE->getOperand(0), gep_type_begin(CPV), 00574 gep_type_end(CPV)); 00575 Out << "))"; 00576 return; 00577 case Instruction::Select: 00578 Out << '('; 00579 printConstant(CE->getOperand(0)); 00580 Out << '?'; 00581 printConstant(CE->getOperand(1)); 00582 Out << ':'; 00583 printConstant(CE->getOperand(2)); 00584 Out << ')'; 00585 return; 00586 case Instruction::Add: 00587 case Instruction::Sub: 00588 case Instruction::Mul: 00589 case Instruction::Div: 00590 case Instruction::Rem: 00591 case Instruction::And: 00592 case Instruction::Or: 00593 case Instruction::Xor: 00594 case Instruction::SetEQ: 00595 case Instruction::SetNE: 00596 case Instruction::SetLT: 00597 case Instruction::SetLE: 00598 case Instruction::SetGT: 00599 case Instruction::SetGE: 00600 case Instruction::Shl: 00601 case Instruction::Shr: 00602 Out << '('; 00603 printConstant(CE->getOperand(0)); 00604 switch (CE->getOpcode()) { 00605 case Instruction::Add: Out << " + "; break; 00606 case Instruction::Sub: Out << " - "; break; 00607 case Instruction::Mul: Out << " * "; break; 00608 case Instruction::Div: Out << " / "; break; 00609 case Instruction::Rem: Out << " % "; break; 00610 case Instruction::And: Out << " & "; break; 00611 case Instruction::Or: Out << " | "; break; 00612 case Instruction::Xor: Out << " ^ "; break; 00613 case Instruction::SetEQ: Out << " == "; break; 00614 case Instruction::SetNE: Out << " != "; break; 00615 case Instruction::SetLT: Out << " < "; break; 00616 case Instruction::SetLE: Out << " <= "; break; 00617 case Instruction::SetGT: Out << " > "; break; 00618 case Instruction::SetGE: Out << " >= "; break; 00619 case Instruction::Shl: Out << " << "; break; 00620 case Instruction::Shr: Out << " >> "; break; 00621 default: assert(0 && "Illegal opcode here!"); 00622 } 00623 printConstant(CE->getOperand(1)); 00624 Out << ')'; 00625 return; 00626 00627 default: 00628 std::cerr << "CWriter Error: Unhandled constant expression: " 00629 << *CE << "\n"; 00630 abort(); 00631 } 00632 } else if (isa<UndefValue>(CPV) && CPV->getType()->isFirstClassType()) { 00633 Out << "(("; 00634 printType(Out, CPV->getType()); 00635 Out << ")/*UNDEF*/0)"; 00636 return; 00637 } 00638 00639 switch (CPV->getType()->getTypeID()) { 00640 case Type::BoolTyID: 00641 Out << (CPV == ConstantBool::False ? '0' : '1'); break; 00642 case Type::SByteTyID: 00643 case Type::ShortTyID: 00644 Out << cast<ConstantSInt>(CPV)->getValue(); break; 00645 case Type::IntTyID: 00646 if ((int)cast<ConstantSInt>(CPV)->getValue() == (int)0x80000000) 00647 Out << "((int)0x80000000U)"; // Handle MININT specially to avoid warning 00648 else 00649 Out << cast<ConstantSInt>(CPV)->getValue(); 00650 break; 00651 00652 case Type::LongTyID: 00653 if (cast<ConstantSInt>(CPV)->isMinValue()) 00654 Out << "(/*INT64_MIN*/(-9223372036854775807LL)-1)"; 00655 else 00656 Out << cast<ConstantSInt>(CPV)->getValue() << "ll"; break; 00657 00658 case Type::UByteTyID: 00659 case Type::UShortTyID: 00660 Out << cast<ConstantUInt>(CPV)->getValue(); break; 00661 case Type::UIntTyID: 00662 Out << cast<ConstantUInt>(CPV)->getValue() << 'u'; break; 00663 case Type::ULongTyID: 00664 Out << cast<ConstantUInt>(CPV)->getValue() << "ull"; break; 00665 00666 case Type::FloatTyID: 00667 case Type::DoubleTyID: { 00668 ConstantFP *FPC = cast<ConstantFP>(CPV); 00669 std::map<const ConstantFP*, unsigned>::iterator I = FPConstantMap.find(FPC); 00670 if (I != FPConstantMap.end()) { 00671 // Because of FP precision problems we must load from a stack allocated 00672 // value that holds the value in hex. 00673 Out << "(*(" << (FPC->getType() == Type::FloatTy ? "float" : "double") 00674 << "*)&FPConstant" << I->second << ')'; 00675 } else { 00676 if (IsNAN(FPC->getValue())) { 00677 // The value is NaN 00678 00679 // The prefix for a quiet NaN is 0x7FF8. For a signalling NaN, 00680 // it's 0x7ff4. 00681 const unsigned long QuietNaN = 0x7ff8UL; 00682 const unsigned long SignalNaN = 0x7ff4UL; 00683 00684 // We need to grab the first part of the FP # 00685 char Buffer[100]; 00686 00687 uint64_t ll = DoubleToBits(FPC->getValue()); 00688 sprintf(Buffer, "0x%llx", static_cast<long long>(ll)); 00689 00690 std::string Num(&Buffer[0], &Buffer[6]); 00691 unsigned long Val = strtoul(Num.c_str(), 0, 16); 00692 00693 if (FPC->getType() == Type::FloatTy) 00694 Out << "LLVM_NAN" << (Val == QuietNaN ? "" : "S") << "F(\"" 00695 << Buffer << "\") /*nan*/ "; 00696 else 00697 Out << "LLVM_NAN" << (Val == QuietNaN ? "" : "S") << "(\"" 00698 << Buffer << "\") /*nan*/ "; 00699 } else if (IsInf(FPC->getValue())) { 00700 // The value is Inf 00701 if (FPC->getValue() < 0) Out << '-'; 00702 Out << "LLVM_INF" << (FPC->getType() == Type::FloatTy ? "F" : "") 00703 << " /*inf*/ "; 00704 } else { 00705 std::string Num; 00706 #if HAVE_PRINTF_A 00707 // Print out the constant as a floating point number. 00708 char Buffer[100]; 00709 sprintf(Buffer, "%a", FPC->getValue()); 00710 Num = Buffer; 00711 #else 00712 Num = ftostr(FPC->getValue()); 00713 #endif 00714 Out << Num; 00715 } 00716 } 00717 break; 00718 } 00719 00720 case Type::ArrayTyID: 00721 if (isa<ConstantAggregateZero>(CPV) || isa<UndefValue>(CPV)) { 00722 const ArrayType *AT = cast<ArrayType>(CPV->getType()); 00723 Out << '{'; 00724 if (AT->getNumElements()) { 00725 Out << ' '; 00726 Constant *CZ = Constant::getNullValue(AT->getElementType()); 00727 printConstant(CZ); 00728 for (unsigned i = 1, e = AT->getNumElements(); i != e; ++i) { 00729 Out << ", "; 00730 printConstant(CZ); 00731 } 00732 } 00733 Out << " }"; 00734 } else { 00735 printConstantArray(cast<ConstantArray>(CPV)); 00736 } 00737 break; 00738 00739 case Type::PackedTyID: 00740 if (isa<ConstantAggregateZero>(CPV) || isa<UndefValue>(CPV)) { 00741 const PackedType *AT = cast<PackedType>(CPV->getType()); 00742 Out << '{'; 00743 if (AT->getNumElements()) { 00744 Out << ' '; 00745 Constant *CZ = Constant::getNullValue(AT->getElementType()); 00746 printConstant(CZ); 00747 for (unsigned i = 1, e = AT->getNumElements(); i != e; ++i) { 00748 Out << ", "; 00749 printConstant(CZ); 00750 } 00751 } 00752 Out << " }"; 00753 } else { 00754 printConstantPacked(cast<ConstantPacked>(CPV)); 00755 } 00756 break; 00757 00758 case Type::StructTyID: 00759 if (isa<ConstantAggregateZero>(CPV) || isa<UndefValue>(CPV)) { 00760 const StructType *ST = cast<StructType>(CPV->getType()); 00761 Out << '{'; 00762 if (ST->getNumElements()) { 00763 Out << ' '; 00764 printConstant(Constant::getNullValue(ST->getElementType(0))); 00765 for (unsigned i = 1, e = ST->getNumElements(); i != e; ++i) { 00766 Out << ", "; 00767 printConstant(Constant::getNullValue(ST->getElementType(i))); 00768 } 00769 } 00770 Out << " }"; 00771 } else { 00772 Out << '{'; 00773 if (CPV->getNumOperands()) { 00774 Out << ' '; 00775 printConstant(cast<Constant>(CPV->getOperand(0))); 00776 for (unsigned i = 1, e = CPV->getNumOperands(); i != e; ++i) { 00777 Out << ", "; 00778 printConstant(cast<Constant>(CPV->getOperand(i))); 00779 } 00780 } 00781 Out << " }"; 00782 } 00783 break; 00784 00785 case Type::PointerTyID: 00786 if (isa<ConstantPointerNull>(CPV)) { 00787 Out << "(("; 00788 printType(Out, CPV->getType()); 00789 Out << ")/*NULL*/0)"; 00790 break; 00791 } else if (GlobalValue *GV = dyn_cast<GlobalValue>(CPV)) { 00792 writeOperand(GV); 00793 break; 00794 } 00795 // FALL THROUGH 00796 default: 00797 std::cerr << "Unknown constant type: " << *CPV << "\n"; 00798 abort(); 00799 } 00800 } 00801 00802 void CWriter::writeOperandInternal(Value *Operand) { 00803 if (Instruction *I = dyn_cast<Instruction>(Operand)) 00804 if (isInlinableInst(*I) && !isDirectAlloca(I)) { 00805 // Should we inline this instruction to build a tree? 00806 Out << '('; 00807 visit(*I); 00808 Out << ')'; 00809 return; 00810 } 00811 00812 Constant* CPV = dyn_cast<Constant>(Operand); 00813 if (CPV && !isa<GlobalValue>(CPV)) { 00814 printConstant(CPV); 00815 } else { 00816 Out << Mang->getValueName(Operand); 00817 } 00818 } 00819 00820 void CWriter::writeOperand(Value *Operand) { 00821 if (isa<GlobalVariable>(Operand) || isDirectAlloca(Operand)) 00822 Out << "(&"; // Global variables are references as their addresses by llvm 00823 00824 writeOperandInternal(Operand); 00825 00826 if (isa<GlobalVariable>(Operand) || isDirectAlloca(Operand)) 00827 Out << ')'; 00828 } 00829 00830 // generateCompilerSpecificCode - This is where we add conditional compilation 00831 // directives to cater to specific compilers as need be. 00832 // 00833 static void generateCompilerSpecificCode(std::ostream& Out) { 00834 // Alloca is hard to get, and we don't want to include stdlib.h here. 00835 Out << "/* get a declaration for alloca */\n" 00836 << "#if defined(__CYGWIN__) || defined(__MINGW32__)\n" 00837 << "extern void *_alloca(unsigned long);\n" 00838 << "#define alloca(x) _alloca(x)\n" 00839 << "#elif defined(__APPLE__)\n" 00840 << "extern void *__builtin_alloca(unsigned long);\n" 00841 << "#define alloca(x) __builtin_alloca(x)\n" 00842 << "#elif defined(__sun__)\n" 00843 << "#if defined(__sparcv9)\n" 00844 << "extern void *__builtin_alloca(unsigned long);\n" 00845 << "#else\n" 00846 << "extern void *__builtin_alloca(unsigned int);\n" 00847 << "#endif\n" 00848 << "#define alloca(x) __builtin_alloca(x)\n" 00849 << "#elif defined(__FreeBSD__) || defined(__OpenBSD__)\n" 00850 << "#define alloca(x) __builtin_alloca(x)\n" 00851 << "#elif !defined(_MSC_VER)\n" 00852 << "#include <alloca.h>\n" 00853 << "#endif\n\n"; 00854 00855 // We output GCC specific attributes to preserve 'linkonce'ness on globals. 00856 // If we aren't being compiled with GCC, just drop these attributes. 00857 Out << "#ifndef __GNUC__ /* Can only support \"linkonce\" vars with GCC */\n" 00858 << "#define __attribute__(X)\n" 00859 << "#endif\n\n"; 00860 00861 #if 0 00862 // At some point, we should support "external weak" vs. "weak" linkages. 00863 // On Mac OS X, "external weak" is spelled "__attribute__((weak_import))". 00864 Out << "#if defined(__GNUC__) && defined(__APPLE_CC__)\n" 00865 << "#define __EXTERNAL_WEAK__ __attribute__((weak_import))\n" 00866 << "#elif defined(__GNUC__)\n" 00867 << "#define __EXTERNAL_WEAK__ __attribute__((weak))\n" 00868 << "#else\n" 00869 << "#define __EXTERNAL_WEAK__\n" 00870 << "#endif\n\n"; 00871 #endif 00872 00873 // For now, turn off the weak linkage attribute on Mac OS X. (See above.) 00874 Out << "#if defined(__GNUC__) && defined(__APPLE_CC__)\n" 00875 << "#define __ATTRIBUTE_WEAK__\n" 00876 << "#elif defined(__GNUC__)\n" 00877 << "#define __ATTRIBUTE_WEAK__ __attribute__((weak))\n" 00878 << "#else\n" 00879 << "#define __ATTRIBUTE_WEAK__\n" 00880 << "#endif\n\n"; 00881 00882 // Define NaN and Inf as GCC builtins if using GCC, as 0 otherwise 00883 // From the GCC documentation: 00884 // 00885 // double __builtin_nan (const char *str) 00886 // 00887 // This is an implementation of the ISO C99 function nan. 00888 // 00889 // Since ISO C99 defines this function in terms of strtod, which we do 00890 // not implement, a description of the parsing is in order. The string is 00891 // parsed as by strtol; that is, the base is recognized by leading 0 or 00892 // 0x prefixes. The number parsed is placed in the significand such that 00893 // the least significant bit of the number is at the least significant 00894 // bit of the significand. The number is truncated to fit the significand 00895 // field provided. The significand is forced to be a quiet NaN. 00896 // 00897 // This function, if given a string literal, is evaluated early enough 00898 // that it is considered a compile-time constant. 00899 // 00900 // float __builtin_nanf (const char *str) 00901 // 00902 // Similar to __builtin_nan, except the return type is float. 00903 // 00904 // double __builtin_inf (void) 00905 // 00906 // Similar to __builtin_huge_val, except a warning is generated if the 00907 // target floating-point format does not support infinities. This 00908 // function is suitable for implementing the ISO C99 macro INFINITY. 00909 // 00910 // float __builtin_inff (void) 00911 // 00912 // Similar to __builtin_inf, except the return type is float. 00913 Out << "#ifdef __GNUC__\n" 00914 << "#define LLVM_NAN(NanStr) __builtin_nan(NanStr) /* Double */\n" 00915 << "#define LLVM_NANF(NanStr) __builtin_nanf(NanStr) /* Float */\n" 00916 << "#define LLVM_NANS(NanStr) __builtin_nans(NanStr) /* Double */\n" 00917 << "#define LLVM_NANSF(NanStr) __builtin_nansf(NanStr) /* Float */\n" 00918 << "#define LLVM_INF __builtin_inf() /* Double */\n" 00919 << "#define LLVM_INFF __builtin_inff() /* Float */\n" 00920 << "#define LLVM_PREFETCH(addr,rw,locality) " 00921 "__builtin_prefetch(addr,rw,locality)\n" 00922 << "#define __ATTRIBUTE_CTOR__ __attribute__((constructor))\n" 00923 << "#define __ATTRIBUTE_DTOR__ __attribute__((destructor))\n" 00924 << "#else\n" 00925 << "#define LLVM_NAN(NanStr) ((double)0.0) /* Double */\n" 00926 << "#define LLVM_NANF(NanStr) 0.0F /* Float */\n" 00927 << "#define LLVM_NANS(NanStr) ((double)0.0) /* Double */\n" 00928 << "#define LLVM_NANSF(NanStr) 0.0F /* Float */\n" 00929 << "#define LLVM_INF ((double)0.0) /* Double */\n" 00930 << "#define LLVM_INFF 0.0F /* Float */\n" 00931 << "#define LLVM_PREFETCH(addr,rw,locality) /* PREFETCH */\n" 00932 << "#define __ATTRIBUTE_CTOR__\n" 00933 << "#define __ATTRIBUTE_DTOR__\n" 00934 << "#endif\n\n"; 00935 00936 // Output target-specific code that should be inserted into main. 00937 Out << "#define CODE_FOR_MAIN() /* Any target-specific code for main()*/\n"; 00938 // On X86, set the FP control word to 64-bits of precision instead of 80 bits. 00939 Out << "#if defined(__GNUC__) && !defined(__llvm__)\n" 00940 << "#if defined(i386) || defined(__i386__) || defined(__i386) || " 00941 << "defined(__x86_64__)\n" 00942 << "#undef CODE_FOR_MAIN\n" 00943 << "#define CODE_FOR_MAIN() \\\n" 00944 << " {short F;__asm__ (\"fnstcw %0\" : \"=m\" (*&F)); \\\n" 00945 << " F=(F&~0x300)|0x200;__asm__(\"fldcw %0\"::\"m\"(*&F));}\n" 00946 << "#endif\n#endif\n"; 00947 00948 } 00949 00950 /// FindStaticTors - Given a static ctor/dtor list, unpack its contents into 00951 /// the StaticTors set. 00952 static void FindStaticTors(GlobalVariable *GV, std::set<Function*> &StaticTors){ 00953 ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer()); 00954 if (!InitList) return; 00955 00956 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) 00957 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){ 00958 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs. 00959 00960 if (CS->getOperand(1)->isNullValue()) 00961 return; // Found a null terminator, exit printing. 00962 Constant *FP = CS->getOperand(1); 00963 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(FP)) 00964 if (CE->getOpcode() == Instruction::Cast) 00965 FP = CE->getOperand(0); 00966 if (Function *F = dyn_cast<Function>(FP)) 00967 StaticTors.insert(F); 00968 } 00969 } 00970 00971 enum SpecialGlobalClass { 00972 NotSpecial = 0, 00973 GlobalCtors, GlobalDtors, 00974 NotPrinted 00975 }; 00976 00977 /// getGlobalVariableClass - If this is a global that is specially recognized 00978 /// by LLVM, return a code that indicates how we should handle it. 00979 static SpecialGlobalClass getGlobalVariableClass(const GlobalVariable *GV) { 00980 // If this is a global ctors/dtors list, handle it now. 00981 if (GV->hasAppendingLinkage() && GV->use_empty()) { 00982 if (GV->getName() == "llvm.global_ctors") 00983 return GlobalCtors; 00984 else if (GV->getName() == "llvm.global_dtors") 00985 return GlobalDtors; 00986 } 00987 00988 // Otherwise, it it is other metadata, don't print it. This catches things 00989 // like debug information. 00990 if (GV->getSection() == "llvm.metadata") 00991 return NotPrinted; 00992 00993 return NotSpecial; 00994 } 00995 00996 00997 bool CWriter::doInitialization(Module &M) { 00998 // Initialize 00999 TheModule = &M; 01000 01001 IL.AddPrototypes(M); 01002 01003 // Ensure that all structure types have names... 01004 Mang = new Mangler(M); 01005 Mang->markCharUnacceptable('.'); 01006 01007 // Keep track of which functions are static ctors/dtors so they can have 01008 // an attribute added to their prototypes. 01009 std::set<Function*> StaticCtors, StaticDtors; 01010 for (Module::global_iterator I = M.global_begin(), E = M.global_end(); 01011 I != E; ++I) { 01012 switch (getGlobalVariableClass(I)) { 01013 default: break; 01014 case GlobalCtors: 01015 FindStaticTors(I, StaticCtors); 01016 break; 01017 case GlobalDtors: 01018 FindStaticTors(I, StaticDtors); 01019 break; 01020 } 01021 } 01022 01023 // get declaration for alloca 01024 Out << "/* Provide Declarations */\n"; 01025 Out << "#include <stdarg.h>\n"; // Varargs support 01026 Out << "#include <setjmp.h>\n"; // Unwind support 01027 generateCompilerSpecificCode(Out); 01028 01029 // Provide a definition for `bool' if not compiling with a C++ compiler. 01030 Out << "\n" 01031 << "#ifndef __cplusplus\ntypedef unsigned char bool;\n#endif\n" 01032 01033 << "\n\n/* Support for floating point constants */\n" 01034 << "typedef unsigned long long ConstantDoubleTy;\n" 01035 << "typedef unsigned int ConstantFloatTy;\n" 01036 01037 << "\n\n/* Global Declarations */\n"; 01038 01039 // First output all the declarations for the program, because C requires 01040 // Functions & globals to be declared before they are used. 01041 // 01042 01043 // Loop over the symbol table, emitting all named constants... 01044 printModuleTypes(M.getSymbolTable()); 01045 01046 // Global variable declarations... 01047 if (!M.global_empty()) { 01048 Out << "\n/* External Global Variable Declarations */\n"; 01049 for (Module::global_iterator I = M.global_begin(), E = M.global_end(); 01050 I != E; ++I) { 01051 if (I->hasExternalLinkage()) { 01052 Out << "extern "; 01053 printType(Out, I->getType()->getElementType(), Mang->getValueName(I)); 01054 Out << ";\n"; 01055 } 01056 } 01057 } 01058 01059 // Function declarations 01060 Out << "\n/* Function Declarations */\n"; 01061 Out << "double fmod(double, double);\n"; // Support for FP rem 01062 Out << "float fmodf(float, float);\n"; 01063 01064 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) { 01065 // Don't print declarations for intrinsic functions. 01066 if (!I->getIntrinsicID() && 01067 I->getName() != "setjmp" && I->getName() != "longjmp") { 01068 printFunctionSignature(I, true); 01069 if (I->hasWeakLinkage() || I->hasLinkOnceLinkage()) 01070 Out << " __ATTRIBUTE_WEAK__"; 01071 if (StaticCtors.count(I)) 01072 Out << " __ATTRIBUTE_CTOR__"; 01073 if (StaticDtors.count(I)) 01074 Out << " __ATTRIBUTE_DTOR__"; 01075 Out << ";\n"; 01076 } 01077 } 01078 01079 // Output the global variable declarations 01080 if (!M.global_empty()) { 01081 Out << "\n\n/* Global Variable Declarations */\n"; 01082 for (Module::global_iterator I = M.global_begin(), E = M.global_end(); 01083 I != E; ++I) 01084 if (!I->isExternal()) { 01085 // Ignore special globals, such as debug info. 01086 if (getGlobalVariableClass(I)) 01087 continue; 01088 01089 if (I->hasInternalLinkage()) 01090 Out << "static "; 01091 else 01092 Out << "extern "; 01093 printType(Out, I->getType()->getElementType(), Mang->getValueName(I)); 01094 01095 if (I->hasLinkOnceLinkage()) 01096 Out << " __attribute__((common))"; 01097 else if (I->hasWeakLinkage()) 01098 Out << " __ATTRIBUTE_WEAK__"; 01099 Out << ";\n"; 01100 } 01101 } 01102 01103 // Output the global variable definitions and contents... 01104 if (!M.global_empty()) { 01105 Out << "\n\n/* Global Variable Definitions and Initialization */\n"; 01106 for (Module::global_iterator I = M.global_begin(), E = M.global_end(); 01107 I != E; ++I) 01108 if (!I->isExternal()) { 01109 // Ignore special globals, such as debug info. 01110 if (getGlobalVariableClass(I)) 01111 continue; 01112 01113 if (I->hasInternalLinkage()) 01114 Out << "static "; 01115 printType(Out, I->getType()->getElementType(), Mang->getValueName(I)); 01116 if (I->hasLinkOnceLinkage()) 01117 Out << " __attribute__((common))"; 01118 else if (I->hasWeakLinkage()) 01119 Out << " __ATTRIBUTE_WEAK__"; 01120 01121 // If the initializer is not null, emit the initializer. If it is null, 01122 // we try to avoid emitting large amounts of zeros. The problem with 01123 // this, however, occurs when the variable has weak linkage. In this 01124 // case, the assembler will complain about the variable being both weak 01125 // and common, so we disable this optimization. 01126 if (!I->getInitializer()->isNullValue()) { 01127 Out << " = " ; 01128 writeOperand(I->getInitializer()); 01129 } else if (I->hasWeakLinkage()) { 01130 // We have to specify an initializer, but it doesn't have to be 01131 // complete. If the value is an aggregate, print out { 0 }, and let 01132 // the compiler figure out the rest of the zeros. 01133 Out << " = " ; 01134 if (isa<StructType>(I->getInitializer()->getType()) || 01135 isa<ArrayType>(I->getInitializer()->getType()) || 01136 isa<PackedType>(I->getInitializer()->getType())) { 01137 Out << "{ 0 }"; 01138 } else { 01139 // Just print it out normally. 01140 writeOperand(I->getInitializer()); 01141 } 01142 } 01143 Out << ";\n"; 01144 } 01145 } 01146 01147 if (!M.empty()) 01148 Out << "\n\n/* Function Bodies */\n"; 01149 return false; 01150 } 01151 01152 01153 /// Output all floating point constants that cannot be printed accurately... 01154 void CWriter::printFloatingPointConstants(Function &F) { 01155 // Scan the module for floating point constants. If any FP constant is used 01156 // in the function, we want to redirect it here so that we do not depend on 01157 // the precision of the printed form, unless the printed form preserves 01158 // precision. 01159 // 01160 static unsigned FPCounter = 0; 01161 for (constant_iterator I = constant_begin(&F), E = constant_end(&F); 01162 I != E; ++I) 01163 if (const ConstantFP *FPC = dyn_cast<ConstantFP>(*I)) 01164 if (!isFPCSafeToPrint(FPC) && // Do not put in FPConstantMap if safe. 01165 !FPConstantMap.count(FPC)) { 01166 double Val = FPC->getValue(); 01167 01168 FPConstantMap[FPC] = FPCounter; // Number the FP constants 01169 01170 if (FPC->getType() == Type::DoubleTy) { 01171 Out << "static const ConstantDoubleTy FPConstant" << FPCounter++ 01172 << " = 0x" << std::hex << DoubleToBits(Val) << std::dec 01173 << "ULL; /* " << Val << " */\n"; 01174 } else if (FPC->getType() == Type::FloatTy) { 01175 Out << "static const ConstantFloatTy FPConstant" << FPCounter++ 01176 << " = 0x" << std::hex << FloatToBits(Val) << std::dec 01177 << "U; /* " << Val << " */\n"; 01178 } else 01179 assert(0 && "Unknown float type!"); 01180 } 01181 01182 Out << '\n'; 01183 } 01184 01185 01186 /// printSymbolTable - Run through symbol table looking for type names. If a 01187 /// type name is found, emit its declaration... 01188 /// 01189 void CWriter::printModuleTypes(const SymbolTable &ST) { 01190 // We are only interested in the type plane of the symbol table. 01191 SymbolTable::type_const_iterator I = ST.type_begin(); 01192 SymbolTable::type_const_iterator End = ST.type_end(); 01193 01194 // If there are no type names, exit early. 01195 if (I == End) return; 01196 01197 // Print out forward declarations for structure types before anything else! 01198 Out << "/* Structure forward decls */\n"; 01199 for (; I != End; ++I) 01200 if (const Type *STy = dyn_cast<StructType>(I->second)) { 01201 std::string Name = "struct l_" + Mang->makeNameProper(I->first); 01202 Out << Name << ";\n"; 01203 TypeNames.insert(std::make_pair(STy, Name)); 01204 } 01205 01206 Out << '\n'; 01207 01208 // Now we can print out typedefs... 01209 Out << "/* Typedefs */\n"; 01210 for (I = ST.type_begin(); I != End; ++I) { 01211 const Type *Ty = cast<Type>(I->second); 01212 std::string Name = "l_" + Mang->makeNameProper(I->first); 01213 Out << "typedef "; 01214 printType(Out, Ty, Name); 01215 Out << ";\n"; 01216 } 01217 01218 Out << '\n'; 01219 01220 // Keep track of which structures have been printed so far... 01221 std::set<const StructType *> StructPrinted; 01222 01223 // Loop over all structures then push them into the stack so they are 01224 // printed in the correct order. 01225 // 01226 Out << "/* Structure contents */\n"; 01227 for (I = ST.type_begin(); I != End; ++I) 01228 if (const StructType *STy = dyn_cast<StructType>(I->second)) 01229 // Only print out used types! 01230 printContainedStructs(STy, StructPrinted); 01231 } 01232 01233 // Push the struct onto the stack and recursively push all structs 01234 // this one depends on. 01235 // 01236 // TODO: Make this work properly with packed types 01237 // 01238 void CWriter::printContainedStructs(const Type *Ty, 01239 std::set<const StructType*> &StructPrinted){ 01240 // Don't walk through pointers. 01241 if (isa<PointerType>(Ty) || Ty->isPrimitiveType()) return; 01242 01243 // Print all contained types first. 01244 for (Type::subtype_iterator I = Ty->subtype_begin(), 01245 E = Ty->subtype_end(); I != E; ++I) 01246 printContainedStructs(*I, StructPrinted); 01247 01248 if (const StructType *STy = dyn_cast<StructType>(Ty)) { 01249 // Check to see if we have already printed this struct. 01250 if (StructPrinted.insert(STy).second) { 01251 // Print structure type out. 01252 std::string Name = TypeNames[STy]; 01253 printType(Out, STy, Name, true); 01254 Out << ";\n\n"; 01255 } 01256 } 01257 } 01258 01259 void CWriter::printFunctionSignature(const Function *F, bool Prototype) { 01260 /// isCStructReturn - Should this function actually return a struct by-value? 01261 bool isCStructReturn = F->getCallingConv() == CallingConv::CSRet; 01262 01263 if (F->hasInternalLinkage()) Out << "static "; 01264 01265 // Loop over the arguments, printing them... 01266 const FunctionType *FT = cast<FunctionType>(F->getFunctionType()); 01267 01268 std::stringstream FunctionInnards; 01269 01270 // Print out the name... 01271 FunctionInnards << Mang->getValueName(F) << '('; 01272 01273 bool PrintedArg = false; 01274 if (!F->isExternal()) { 01275 if (!F->arg_empty()) { 01276 Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end(); 01277 01278 // If this is a struct-return function, don't print the hidden 01279 // struct-return argument. 01280 if (isCStructReturn) { 01281 assert(I != E && "Invalid struct return function!"); 01282 ++I; 01283 } 01284 01285 std::string ArgName; 01286 for (; I != E; ++I) { 01287 if (PrintedArg) FunctionInnards << ", "; 01288 if (I->hasName() || !Prototype) 01289 ArgName = Mang->getValueName(I); 01290 else 01291 ArgName = ""; 01292 printType(FunctionInnards, I->getType(), ArgName); 01293 PrintedArg = true; 01294 } 01295 } 01296 } else { 01297 // Loop over the arguments, printing them. 01298 FunctionType::param_iterator I = FT->param_begin(), E = FT->param_end(); 01299 01300 // If this is a struct-return function, don't print the hidden 01301 // struct-return argument. 01302 if (isCStructReturn) { 01303 assert(I != E && "Invalid struct return function!"); 01304 ++I; 01305 } 01306 01307 for (; I != E; ++I) { 01308 if (PrintedArg) FunctionInnards << ", "; 01309 printType(FunctionInnards, *I); 01310 PrintedArg = true; 01311 } 01312 } 01313 01314 // Finish printing arguments... if this is a vararg function, print the ..., 01315 // unless there are no known types, in which case, we just emit (). 01316 // 01317 if (FT->isVarArg() && PrintedArg) { 01318 if (PrintedArg) FunctionInnards << ", "; 01319 FunctionInnards << "..."; // Output varargs portion of signature! 01320 } else if (!FT->isVarArg() && !PrintedArg) { 01321 FunctionInnards << "void"; // ret() -> ret(void) in C. 01322 } 01323 FunctionInnards << ')'; 01324 01325 // Get the return tpe for the function. 01326 const Type *RetTy; 01327 if (!isCStructReturn) 01328 RetTy = F->getReturnType(); 01329 else { 01330 // If this is a struct-return function, print the struct-return type. 01331 RetTy = cast<PointerType>(FT->getParamType(0))->getElementType(); 01332 } 01333 01334 // Print out the return type and the signature built above. 01335 printType(Out, RetTy, FunctionInnards.str()); 01336 } 01337 01338 void CWriter::printFunction(Function &F) { 01339 printFunctionSignature(&F, false); 01340 Out << " {\n"; 01341 01342 // If this is a struct return function, handle the result with magic. 01343 if (F.getCallingConv() == CallingConv::CSRet) { 01344 const Type *StructTy = 01345 cast<PointerType>(F.arg_begin()->getType())->getElementType(); 01346 Out << " "; 01347 printType(Out, StructTy, "StructReturn"); 01348 Out << "; /* Struct return temporary */\n"; 01349 01350 Out << " "; 01351 printType(Out, F.arg_begin()->getType(), Mang->getValueName(F.arg_begin())); 01352 Out << " = &StructReturn;\n"; 01353 } 01354 01355 bool PrintedVar = false; 01356 01357 // print local variable information for the function 01358 for (inst_iterator I = inst_begin(&F), E = inst_end(&F); I != E; ++I) 01359 if (const AllocaInst *AI = isDirectAlloca(&*I)) { 01360 Out << " "; 01361 printType(Out, AI->getAllocatedType(), Mang->getValueName(AI)); 01362 Out << "; /* Address-exposed local */\n"; 01363 PrintedVar = true; 01364 } else if (I->getType() != Type::VoidTy && !isInlinableInst(*I)) { 01365 Out << " "; 01366 printType(Out, I->getType(), Mang->getValueName(&*I)); 01367 Out << ";\n"; 01368 01369 if (isa<PHINode>(*I)) { // Print out PHI node temporaries as well... 01370 Out << " "; 01371 printType(Out, I->getType(), 01372 Mang->getValueName(&*I)+"__PHI_TEMPORARY"); 01373 Out << ";\n"; 01374 } 01375 PrintedVar = true; 01376 } 01377 01378 if (PrintedVar) 01379 Out << '\n'; 01380 01381 if (F.hasExternalLinkage() && F.getName() == "main") 01382 Out << " CODE_FOR_MAIN();\n"; 01383 01384 // print the basic blocks 01385 for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) { 01386 if (Loop *L = LI->getLoopFor(BB)) { 01387 if (L->getHeader() == BB && L->getParentLoop() == 0) 01388 printLoop(L); 01389 } else { 01390 printBasicBlock(BB); 01391 } 01392 } 01393 01394 Out << "}\n\n"; 01395 } 01396 01397 void CWriter::printLoop(Loop *L) { 01398 Out << " do { /* Syntactic loop '" << L->getHeader()->getName() 01399 << "' to make GCC happy */\n"; 01400 for (unsigned i = 0, e = L->getBlocks().size(); i != e; ++i) { 01401 BasicBlock *BB = L->getBlocks()[i]; 01402 Loop *BBLoop = LI->getLoopFor(BB); 01403 if (BBLoop == L) 01404 printBasicBlock(BB); 01405 else if (BB == BBLoop->getHeader() && BBLoop->getParentLoop() == L) 01406 printLoop(BBLoop); 01407 } 01408 Out << " } while (1); /* end of syntactic loop '" 01409 << L->getHeader()->getName() << "' */\n"; 01410 } 01411 01412 void CWriter::printBasicBlock(BasicBlock *BB) { 01413 01414 // Don't print the label for the basic block if there are no uses, or if 01415 // the only terminator use is the predecessor basic block's terminator. 01416 // We have to scan the use list because PHI nodes use basic blocks too but 01417 // do not require a label to be generated. 01418 // 01419 bool NeedsLabel = false; 01420 for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) 01421 if (isGotoCodeNecessary(*PI, BB)) { 01422 NeedsLabel = true; 01423 break; 01424 } 01425 01426 if (NeedsLabel) Out << Mang->getValueName(BB) << ":\n"; 01427 01428 // Output all of the instructions in the basic block... 01429 for (BasicBlock::iterator II = BB->begin(), E = --BB->end(); II != E; 01430 ++II) { 01431 if (!isInlinableInst(*II) && !isDirectAlloca(II)) { 01432 if (II->getType() != Type::VoidTy) 01433 outputLValue(II); 01434 else 01435 Out << " "; 01436 visit(*II); 01437 Out << ";\n"; 01438 } 01439 } 01440 01441 // Don't emit prefix or suffix for the terminator... 01442 visit(*BB->getTerminator()); 01443 } 01444 01445 01446 // Specific Instruction type classes... note that all of the casts are 01447 // necessary because we use the instruction classes as opaque types... 01448 // 01449 void CWriter::visitReturnInst(ReturnInst &I) { 01450 // If this is a struct return function, return the temporary struct. 01451 if (I.getParent()->getParent()->getCallingConv() == CallingConv::CSRet) { 01452 Out << " return StructReturn;\n"; 01453 return; 01454 } 01455 01456 // Don't output a void return if this is the last basic block in the function 01457 if (I.getNumOperands() == 0 && 01458 &*--I.getParent()->getParent()->end() == I.getParent() && 01459 !I.getParent()->size() == 1) { 01460 return; 01461 } 01462 01463 Out << " return"; 01464 if (I.getNumOperands()) { 01465 Out << ' '; 01466 writeOperand(I.getOperand(0)); 01467 } 01468 Out << ";\n"; 01469 } 01470 01471 void CWriter::visitSwitchInst(SwitchInst &SI) { 01472 01473 Out << " switch ("; 01474 writeOperand(SI.getOperand(0)); 01475 Out << ") {\n default:\n"; 01476 printPHICopiesForSuccessor (SI.getParent(), SI.getDefaultDest(), 2); 01477 printBranchToBlock(SI.getParent(), SI.getDefaultDest(), 2); 01478 Out << ";\n"; 01479 for (unsigned i = 2, e = SI.getNumOperands(); i != e; i += 2) { 01480 Out << " case "; 01481 writeOperand(SI.getOperand(i)); 01482 Out << ":\n"; 01483 BasicBlock *Succ = cast<BasicBlock>(SI.getOperand(i+1)); 01484 printPHICopiesForSuccessor (SI.getParent(), Succ, 2); 01485 printBranchToBlock(SI.getParent(), Succ, 2); 01486 if (Function::iterator(Succ) == next(Function::iterator(SI.getParent()))) 01487 Out << " break;\n"; 01488 } 01489 Out << " }\n"; 01490 } 01491 01492 void CWriter::visitUnreachableInst(UnreachableInst &I) { 01493 Out << " /*UNREACHABLE*/;\n"; 01494 } 01495 01496 bool CWriter::isGotoCodeNecessary(BasicBlock *From, BasicBlock *To) { 01497 /// FIXME: This should be reenabled, but loop reordering safe!! 01498 return true; 01499 01500 if (next(Function::iterator(From)) != Function::iterator(To)) 01501 return true; // Not the direct successor, we need a goto. 01502 01503 //isa<SwitchInst>(From->getTerminator()) 01504 01505 if (LI->getLoopFor(From) != LI->getLoopFor(To)) 01506 return true; 01507 return false; 01508 } 01509 01510 void CWriter::printPHICopiesForSuccessor (BasicBlock *CurBlock, 01511 BasicBlock *Successor, 01512 unsigned Indent) { 01513 for (BasicBlock::iterator I = Successor->begin(); isa<PHINode>(I); ++I) { 01514 PHINode *PN = cast<PHINode>(I); 01515 // Now we have to do the printing. 01516 Value *IV = PN->getIncomingValueForBlock(CurBlock); 01517 if (!isa<UndefValue>(IV)) { 01518 Out << std::string(Indent, ' '); 01519 Out << " " << Mang->getValueName(I) << "__PHI_TEMPORARY = "; 01520 writeOperand(IV); 01521 Out << "; /* for PHI node */\n"; 01522 } 01523 } 01524 } 01525 01526 void CWriter::printBranchToBlock(BasicBlock *CurBB, BasicBlock *Succ, 01527 unsigned Indent) { 01528 if (isGotoCodeNecessary(CurBB, Succ)) { 01529 Out << std::string(Indent, ' ') << " goto "; 01530 writeOperand(Succ); 01531 Out << ";\n"; 01532 } 01533 } 01534 01535 // Branch instruction printing - Avoid printing out a branch to a basic block 01536 // that immediately succeeds the current one. 01537 // 01538 void CWriter::visitBranchInst(BranchInst &I) { 01539 01540 if (I.isConditional()) { 01541 if (isGotoCodeNecessary(I.getParent(), I.getSuccessor(0))) { 01542 Out << " if ("; 01543 writeOperand(I.getCondition()); 01544 Out << ") {\n"; 01545 01546 printPHICopiesForSuccessor (I.getParent(), I.getSuccessor(0), 2); 01547 printBranchToBlock(I.getParent(), I.getSuccessor(0), 2); 01548 01549 if (isGotoCodeNecessary(I.getParent(), I.getSuccessor(1))) { 01550 Out << " } else {\n"; 01551 printPHICopiesForSuccessor (I.getParent(), I.getSuccessor(1), 2); 01552 printBranchToBlock(I.getParent(), I.getSuccessor(1), 2); 01553 } 01554 } else { 01555 // First goto not necessary, assume second one is... 01556 Out << " if (!"; 01557 writeOperand(I.getCondition()); 01558 Out << ") {\n"; 01559 01560 printPHICopiesForSuccessor (I.getParent(), I.getSuccessor(1), 2); 01561 printBranchToBlock(I.getParent(), I.getSuccessor(1), 2); 01562 } 01563 01564 Out << " }\n"; 01565 } else { 01566 printPHICopiesForSuccessor (I.getParent(), I.getSuccessor(0), 0); 01567 printBranchToBlock(I.getParent(), I.getSuccessor(0), 0); 01568 } 01569 Out << "\n"; 01570 } 01571 01572 // PHI nodes get copied into temporary values at the end of predecessor basic 01573 // blocks. We now need to copy these temporary values into the REAL value for 01574 // the PHI. 01575 void CWriter::visitPHINode(PHINode &I) { 01576 writeOperand(&I); 01577 Out << "__PHI_TEMPORARY"; 01578 } 01579 01580 01581 void CWriter::visitBinaryOperator(Instruction &I) { 01582 // binary instructions, shift instructions, setCond instructions. 01583 assert(!isa<PointerType>(I.getType())); 01584 01585 // We must cast the results of binary operations which might be promoted. 01586 bool needsCast = false; 01587 if ((I.getType() == Type::UByteTy) || (I.getType() == Type::SByteTy) 01588 || (I.getType() == Type::UShortTy) || (I.getType() == Type::ShortTy) 01589 || (I.getType() == Type::FloatTy)) { 01590 needsCast = true; 01591 Out << "(("; 01592 printType(Out, I.getType()); 01593 Out << ")("; 01594 } 01595 01596 // If this is a negation operation, print it out as such. For FP, we don't 01597 // want to print "-0.0 - X". 01598 if (BinaryOperator::isNeg(&I)) { 01599 Out << "-("; 01600 writeOperand(BinaryOperator::getNegArgument(cast<BinaryOperator>(&I))); 01601 Out << ")"; 01602 } else if (I.getOpcode() == Instruction::Rem && 01603 I.getType()->isFloatingPoint()) { 01604 // Output a call to fmod/fmodf instead of emitting a%b 01605 if (I.getType() == Type::FloatTy) 01606 Out << "fmodf("; 01607 else 01608 Out << "fmod("; 01609 writeOperand(I.getOperand(0)); 01610 Out << ", "; 01611 writeOperand(I.getOperand(1)); 01612 Out << ")"; 01613 } else { 01614 writeOperand(I.getOperand(0)); 01615 01616 switch (I.getOpcode()) { 01617 case Instruction::Add: Out << " + "; break; 01618 case Instruction::Sub: Out << " - "; break; 01619 case Instruction::Mul: Out << '*'; break; 01620 case Instruction::Div: Out << '/'; break; 01621 case Instruction::Rem: Out << '%'; break; 01622 case Instruction::And: Out << " & "; break; 01623 case Instruction::Or: Out << " | "; break; 01624 case Instruction::Xor: Out << " ^ "; break; 01625 case Instruction::SetEQ: Out << " == "; break; 01626 case Instruction::SetNE: Out << " != "; break; 01627 case Instruction::SetLE: Out << " <= "; break; 01628 case Instruction::SetGE: Out << " >= "; break; 01629 case Instruction::SetLT: Out << " < "; break; 01630 case Instruction::SetGT: Out << " > "; break; 01631 case Instruction::Shl : Out << " << "; break; 01632 case Instruction::Shr : Out << " >> "; break; 01633 default: std::cerr << "Invalid operator type!" << I; abort(); 01634 } 01635 01636 writeOperand(I.getOperand(1)); 01637 } 01638 01639 if (needsCast) { 01640 Out << "))"; 01641 } 01642 } 01643 01644 void CWriter::visitCastInst(CastInst &I) { 01645 if (I.getType() == Type::BoolTy) { 01646 Out << '('; 01647 writeOperand(I.getOperand(0)); 01648 Out << " != 0)"; 01649 return; 01650 } 01651 Out << '('; 01652 printType(Out, I.getType()); 01653 Out << ')'; 01654 if (isa<PointerType>(I.getType())&&I.getOperand(0)->getType()->isIntegral() || 01655 isa<PointerType>(I.getOperand(0)->getType())&&I.getType()->isIntegral()) { 01656 // Avoid "cast to pointer from integer of different size" warnings 01657 Out << "(long)"; 01658 } 01659 01660 writeOperand(I.getOperand(0)); 01661 } 01662 01663 void CWriter::visitSelectInst(SelectInst &I) { 01664 Out << "(("; 01665 writeOperand(I.getCondition()); 01666 Out << ") ? ("; 01667 writeOperand(I.getTrueValue()); 01668 Out << ") : ("; 01669 writeOperand(I.getFalseValue()); 01670 Out << "))"; 01671 } 01672 01673 01674 void CWriter::lowerIntrinsics(Function &F) { 01675 for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) 01676 for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) 01677 if (CallInst *CI = dyn_cast<CallInst>(I++)) 01678 if (Function *F = CI->getCalledFunction()) 01679 switch (F->getIntrinsicID()) { 01680 case Intrinsic::not_intrinsic: 01681 case Intrinsic::vastart: 01682 case Intrinsic::vacopy: 01683 case Intrinsic::vaend: 01684 case Intrinsic::returnaddress: 01685 case Intrinsic::frameaddress: 01686 case Intrinsic::setjmp: 01687 case Intrinsic::longjmp: 01688 case Intrinsic::prefetch: 01689 case Intrinsic::dbg_stoppoint: 01690 // We directly implement these intrinsics 01691 break; 01692 default: 01693 // If this is an intrinsic that directly corresponds to a GCC 01694 // builtin, we handle it. 01695 const char *BuiltinName = ""; 01696 #define GET_GCC_BUILTIN_NAME 01697 #include "llvm/Intrinsics.gen" 01698 #undef GET_GCC_BUILTIN_NAME 01699 // If we handle it, don't lower it. 01700 if (BuiltinName[0]) break; 01701 01702 // All other intrinsic calls we must lower. 01703 Instruction *Before = 0; 01704 if (CI != &BB->front()) 01705 Before = prior(BasicBlock::iterator(CI)); 01706 01707 IL.LowerIntrinsicCall(CI); 01708 if (Before) { // Move iterator to instruction after call 01709 I = Before; ++I; 01710 } else { 01711 I = BB->begin(); 01712 } 01713 break; 01714 } 01715 } 01716 01717 01718 01719 void CWriter::visitCallInst(CallInst &I) { 01720 bool WroteCallee = false; 01721 01722 // Handle intrinsic function calls first... 01723 if (Function *F = I.getCalledFunction()) 01724 if (Intrinsic::ID ID = (Intrinsic::ID)F->getIntrinsicID()) { 01725 switch (ID) { 01726 default: { 01727 // If this is an intrinsic that directly corresponds to a GCC 01728 // builtin, we emit it here. 01729 const char *BuiltinName = ""; 01730 #define GET_GCC_BUILTIN_NAME 01731 #include "llvm/Intrinsics.gen" 01732 #undef GET_GCC_BUILTIN_NAME 01733 assert(BuiltinName[0] && "Unknown LLVM intrinsic!"); 01734 01735 Out << BuiltinName; 01736 WroteCallee = true; 01737 break; 01738 } 01739 case Intrinsic::vastart: 01740 Out << "0; "; 01741 01742 Out << "va_start(*(va_list*)"; 01743 writeOperand(I.getOperand(1)); 01744 Out << ", "; 01745 // Output the last argument to the enclosing function... 01746 if (I.getParent()->getParent()->arg_empty()) { 01747 std::cerr << "The C backend does not currently support zero " 01748 << "argument varargs functions, such as '" 01749 << I.getParent()->getParent()->getName() << "'!\n"; 01750 abort(); 01751 } 01752 writeOperand(--I.getParent()->getParent()->arg_end()); 01753 Out << ')'; 01754 return; 01755 case Intrinsic::vaend: 01756 if (!isa<ConstantPointerNull>(I.getOperand(1))) { 01757 Out << "0; va_end(*(va_list*)"; 01758 writeOperand(I.getOperand(1)); 01759 Out << ')'; 01760 } else { 01761 Out << "va_end(*(va_list*)0)"; 01762 } 01763 return; 01764 case Intrinsic::vacopy: 01765 Out << "0; "; 01766 Out << "va_copy(*(va_list*)"; 01767 writeOperand(I.getOperand(1)); 01768 Out << ", *(va_list*)"; 01769 writeOperand(I.getOperand(2)); 01770 Out << ')'; 01771 return; 01772 case Intrinsic::returnaddress: 01773 Out << "__builtin_return_address("; 01774 writeOperand(I.getOperand(1)); 01775 Out << ')'; 01776 return; 01777 case Intrinsic::frameaddress: 01778 Out << "__builtin_frame_address("; 01779 writeOperand(I.getOperand(1)); 01780 Out << ')'; 01781 return; 01782 case Intrinsic::setjmp: 01783 #if defined(HAVE__SETJMP) && defined(HAVE__LONGJMP) 01784 Out << "_"; // Use _setjmp on systems that support it! 01785 #endif 01786 Out << "setjmp(*(jmp_buf*)"; 01787 writeOperand(I.getOperand(1)); 01788 Out << ')'; 01789 return; 01790 case Intrinsic::longjmp: 01791 #if defined(HAVE__SETJMP) && defined(HAVE__LONGJMP) 01792 Out << "_"; // Use _longjmp on systems that support it! 01793 #endif 01794 Out << "longjmp(*(jmp_buf*)"; 01795 writeOperand(I.getOperand(1)); 01796 Out << ", "; 01797 writeOperand(I.getOperand(2)); 01798 Out << ')'; 01799 return; 01800 case Intrinsic::prefetch: 01801 Out << "LLVM_PREFETCH((const void *)"; 01802 writeOperand(I.getOperand(1)); 01803 Out << ", "; 01804 writeOperand(I.getOperand(2)); 01805 Out << ", "; 01806 writeOperand(I.getOperand(3)); 01807 Out << ")"; 01808 return; 01809 case Intrinsic::dbg_stoppoint: { 01810 // If we use writeOperand directly we get a "u" suffix which is rejected 01811 // by gcc. 01812 DbgStopPointInst &SPI = cast<DbgStopPointInst>(I); 01813 01814 Out << "\n#line " 01815 << SPI.getLine() 01816 << " \"" << SPI.getDirectory() 01817 << SPI.getFileName() << "\"\n"; 01818 return; 01819 } 01820 } 01821 } 01822 01823 Value *Callee = I.getCalledValue(); 01824 01825 // If this is a call to a struct-return function, assign to the first 01826 // parameter instead of passing it to the call. 01827 bool isStructRet = I.getCallingConv() == CallingConv::CSRet; 01828 if (isStructRet) { 01829 Out << "*("; 01830 writeOperand(I.getOperand(1)); 01831 Out << ") = "; 01832 } 01833 01834 if (I.isTailCall()) Out << " /*tail*/ "; 01835 01836 const PointerType *PTy = cast<PointerType>(Callee->getType()); 01837 const FunctionType *FTy = cast<FunctionType>(PTy->getElementType()); 01838 01839 if (!WroteCallee) { 01840 // If this is an indirect call to a struct return function, we need to cast 01841 // the pointer. 01842 bool NeedsCast = isStructRet && !isa<Function>(Callee); 01843 01844 // GCC is a real PITA. It does not permit codegening casts of functions to 01845 // function pointers if they are in a call (it generates a trap instruction 01846 // instead!). We work around this by inserting a cast to void* in between 01847 // the function and the function pointer cast. Unfortunately, we can't just 01848 // form the constant expression here, because the folder will immediately 01849 // nuke it. 01850 // 01851 // Note finally, that this is completely unsafe. ANSI C does not guarantee 01852 // that void* and function pointers have the same size. :( To deal with this 01853 // in the common case, we handle casts where the number of arguments passed 01854 // match exactly. 01855 // 01856 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Callee)) 01857 if (CE->getOpcode() == Instruction::Cast) 01858 if (Function *RF = dyn_cast<Function>(CE->getOperand(0))) { 01859 NeedsCast = true; 01860 Callee = RF; 01861 } 01862 01863 if (NeedsCast) { 01864 // Ok, just cast the pointer type. 01865 Out << "(("; 01866 if (!isStructRet) 01867 printType(Out, I.getCalledValue()->getType()); 01868 else 01869 printStructReturnPointerFunctionType(Out, 01870 cast<PointerType>(I.getCalledValue()->getType())); 01871 Out << ")(void*)"; 01872 } 01873 writeOperand(Callee); 01874 if (NeedsCast) Out << ')'; 01875 } 01876 01877 Out << '('; 01878 01879 unsigned NumDeclaredParams = FTy->getNumParams(); 01880 01881 CallSite::arg_iterator AI = I.op_begin()+1, AE = I.op_end(); 01882 unsigned ArgNo = 0; 01883 if (isStructRet) { // Skip struct return argument. 01884 ++AI; 01885 ++ArgNo; 01886 } 01887 01888 bool PrintedArg = false; 01889 for (; AI != AE; ++AI, ++ArgNo) { 01890 if (PrintedArg) Out << ", "; 01891 if (ArgNo < NumDeclaredParams && 01892 (*AI)->getType() != FTy->getParamType(ArgNo)) { 01893 Out << '('; 01894 printType(Out, FTy->getParamType(ArgNo)); 01895 Out << ')'; 01896 } 01897 writeOperand(*AI); 01898 PrintedArg = true; 01899 } 01900 Out << ')'; 01901 } 01902 01903 void CWriter::visitMallocInst(MallocInst &I) { 01904 assert(0 && "lowerallocations pass didn't work!"); 01905 } 01906 01907 void CWriter::visitAllocaInst(AllocaInst &I) { 01908 Out << '('; 01909 printType(Out, I.getType()); 01910 Out << ") alloca(sizeof("; 01911 printType(Out, I.getType()->getElementType()); 01912 Out << ')'; 01913 if (I.isArrayAllocation()) { 01914 Out << " * " ; 01915 writeOperand(I.getOperand(0)); 01916 } 01917 Out << ')'; 01918 } 01919 01920 void CWriter::visitFreeInst(FreeInst &I) { 01921 assert(0 && "lowerallocations pass didn't work!"); 01922 } 01923 01924 void CWriter::printIndexingExpression(Value *Ptr, gep_type_iterator I, 01925 gep_type_iterator E) { 01926 bool HasImplicitAddress = false; 01927 // If accessing a global value with no indexing, avoid *(&GV) syndrome 01928 if (GlobalValue *V = dyn_cast<GlobalValue>(Ptr)) { 01929 HasImplicitAddress = true; 01930 } else if (isDirectAlloca(Ptr)) { 01931 HasImplicitAddress = true; 01932 } 01933 01934 if (I == E) { 01935 if (!HasImplicitAddress) 01936 Out << '*'; // Implicit zero first argument: '*x' is equivalent to 'x[0]' 01937 01938 writeOperandInternal(Ptr); 01939 return; 01940 } 01941 01942 const Constant *CI = dyn_cast<Constant>(I.getOperand()); 01943 if (HasImplicitAddress && (!CI || !CI->isNullValue())) 01944 Out << "(&"; 01945 01946 writeOperandInternal(Ptr); 01947 01948 if (HasImplicitAddress && (!CI || !CI->isNullValue())) { 01949 Out << ')'; 01950 HasImplicitAddress = false; // HIA is only true if we haven't addressed yet 01951 } 01952 01953 assert(!HasImplicitAddress || (CI && CI->isNullValue()) && 01954 "Can only have implicit address with direct accessing"); 01955 01956 if (HasImplicitAddress) { 01957 ++I; 01958 } else if (CI && CI->isNullValue()) { 01959 gep_type_iterator TmpI = I; ++TmpI; 01960 01961 // Print out the -> operator if possible... 01962 if (TmpI != E && isa<StructType>(*TmpI)) { 01963 Out << (HasImplicitAddress ? "." : "->"); 01964 Out << "field" << cast<ConstantUInt>(TmpI.getOperand())->getValue(); 01965 I = ++TmpI; 01966 } 01967 } 01968 01969 for (; I != E; ++I) 01970 if (isa<StructType>(*I)) { 01971 Out << ".field" << cast<ConstantUInt>(I.getOperand())->getValue(); 01972 } else { 01973 Out << '['; 01974 writeOperand(I.getOperand()); 01975 Out << ']'; 01976 } 01977 } 01978 01979 void CWriter::visitLoadInst(LoadInst &I) { 01980 Out << '*'; 01981 if (I.isVolatile()) { 01982 Out << "(("; 01983 printType(Out, I.getType(), "volatile*"); 01984 Out << ")"; 01985 } 01986 01987 writeOperand(I.getOperand(0)); 01988 01989 if (I.isVolatile()) 01990 Out << ')'; 01991 } 01992 01993 void CWriter::visitStoreInst(StoreInst &I) { 01994 Out << '*'; 01995 if (I.isVolatile()) { 01996 Out << "(("; 01997 printType(Out, I.getOperand(0)->getType(), " volatile*"); 01998 Out << ")"; 01999 } 02000 writeOperand(I.getPointerOperand()); 02001 if (I.isVolatile()) Out << ')'; 02002 Out << " = "; 02003 writeOperand(I.getOperand(0)); 02004 } 02005 02006 void CWriter::visitGetElementPtrInst(GetElementPtrInst &I) { 02007 Out << '&'; 02008 printIndexingExpression(I.getPointerOperand(), gep_type_begin(I), 02009 gep_type_end(I)); 02010 } 02011 02012 void CWriter::visitVAArgInst(VAArgInst &I) { 02013 Out << "va_arg(*(va_list*)"; 02014 writeOperand(I.getOperand(0)); 02015 Out << ", "; 02016 printType(Out, I.getType()); 02017 Out << ");\n "; 02018 } 02019 02020 //===----------------------------------------------------------------------===// 02021 // External Interface declaration 02022 //===----------------------------------------------------------------------===// 02023 02024 bool CTargetMachine::addPassesToEmitFile(PassManager &PM, std::ostream &o, 02025 CodeGenFileType FileType, bool Fast) { 02026 if (FileType != TargetMachine::AssemblyFile) return true; 02027 02028 PM.add(createLowerGCPass()); 02029 PM.add(createLowerAllocationsPass(true)); 02030 PM.add(createLowerInvokePass()); 02031 PM.add(createCFGSimplificationPass()); // clean up after lower invoke. 02032 PM.add(new CBackendNameAllUsedStructsAndMergeFunctions()); 02033 PM.add(new CWriter(o)); 02034 return false; 02035 }