//===-- EmitAssembly.cpp - Emit Sparc Specific .s File ---------------------==// // // This file implements all of the stuff neccesary to output a .s file from // LLVM. The code in this file assumes that the specified module has already // been compiled into the internal data structures of the Module. // // This code largely consists of two LLVM Pass's: a MethodPass and a Pass. The // MethodPass is pipelined together with all of the rest of the code generation // stages, and the Pass runs at the end to emit code for global variables and // such. // //===----------------------------------------------------------------------===// #include "SparcInternals.h" #include "llvm/CodeGen/MachineInstr.h" #include "llvm/CodeGen/MachineCodeForMethod.h" #include "llvm/GlobalVariable.h" #include "llvm/ConstantVals.h" #include "llvm/DerivedTypes.h" #include "llvm/Annotation.h" #include "llvm/BasicBlock.h" #include "llvm/Function.h" #include "llvm/Module.h" #include "llvm/SlotCalculator.h" #include "llvm/Assembly/Writer.h" #include "Support/StringExtras.h" #include "Support/HashExtras.h" #include using std::string; namespace { class GlobalIdTable: public Annotation { static AnnotationID AnnotId; friend class AsmPrinter; // give access to AnnotId typedef std::hash_map ValIdMap; typedef ValIdMap::const_iterator ValIdMapConstIterator; typedef ValIdMap:: iterator ValIdMapIterator; public: SlotCalculator *Table; // map anonymous values to unique integer IDs ValIdMap valToIdMap; // used for values not handled by SlotCalculator GlobalIdTable(Module* M) : Annotation(AnnotId) { Table = new SlotCalculator(M, true); } ~GlobalIdTable() { delete Table; Table = NULL; valToIdMap.clear(); } }; AnnotationID GlobalIdTable::AnnotId = AnnotationManager::getID("ASM PRINTER GLOBAL TABLE ANNOT"); //===---------------------------------------------------------------------===// // Code Shared By the two printer passes, as a mixin //===---------------------------------------------------------------------===// class AsmPrinter { GlobalIdTable* idTable; public: std::ostream &toAsm; const TargetMachine &Target; enum Sections { Unknown, Text, ReadOnlyData, InitRWData, UninitRWData, } CurSection; AsmPrinter(std::ostream &os, const TargetMachine &T) : idTable(0), toAsm(os), Target(T), CurSection(Unknown) {} // (start|end)(Module|Function) - Callback methods to be invoked by subclasses void startModule(Module *M) { // Create the global id table if it does not already exist idTable = (GlobalIdTable*) M->getAnnotation(GlobalIdTable::AnnotId); if (idTable == NULL) { idTable = new GlobalIdTable(M); M->addAnnotation(idTable); } } void startFunction(Function *F) { // Make sure the slot table has information about this function... idTable->Table->incorporateFunction(F); } void endFunction(Function *F) { idTable->Table->purgeFunction(); // Forget all about F } void endModule() { } // Check if a name is external or accessible from external code. // Only functions can currently be external. "main" is the only name // that is visible externally. bool isExternal(const Value* V) { const Function *F = dyn_cast(V); return F && (F->isExternal() || F->getName() == "main"); } // enterSection - Use this method to enter a different section of the output // executable. This is used to only output neccesary section transitions. // void enterSection(enum Sections S) { if (S == CurSection) return; // Only switch section if neccesary CurSection = S; toAsm << "\n\t.section "; switch (S) { default: assert(0 && "Bad section name!"); case Text: toAsm << "\".text\""; break; case ReadOnlyData: toAsm << "\".rodata\",#alloc"; break; case InitRWData: toAsm << "\".data\",#alloc,#write"; break; case UninitRWData: toAsm << "\".bss\",#alloc,#write\nBbss.bss:"; break; } toAsm << "\n"; } static std::string getValidSymbolName(const string &S) { string Result; // Symbol names in Sparc assembly language have these rules: // (a) Must match { letter | _ | . | $ } { letter | _ | . | $ | digit }* // (b) A name beginning in "." is treated as a local name. // (c) Names beginning with "_" are reserved by ANSI C and shd not be used. // if (S[0] == '_' || isdigit(S[0])) Result += "ll"; for (unsigned i = 0; i < S.size(); ++i) { char C = S[i]; if (C == '_' || C == '.' || C == '$' || isalpha(C) || isdigit(C)) Result += C; else { Result += '_'; Result += char('0' + ((unsigned char)C >> 4)); Result += char('0' + (C & 0xF)); } } return Result; } // getID - Return a valid identifier for the specified value. Base it on // the name of the identifier if possible (qualified by the type), and // use a numbered value based on prefix otherwise. // FPrefix is always prepended to the output identifier. // string getID(const Value *V, const char *Prefix, const char *FPrefix = 0) { string Result = FPrefix ? FPrefix : ""; // "Forced prefix" Result = Result + (V->hasName()? V->getName() : string(Prefix)); // Qualify all internal names with a unique id. if (!isExternal(V)) { int valId = idTable->Table->getValSlot(V); if (valId == -1) { GlobalIdTable::ValIdMapConstIterator I = idTable->valToIdMap.find(V); if (I == idTable->valToIdMap.end()) valId = idTable->valToIdMap[V] = idTable->valToIdMap.size(); else valId = I->second; } Result = Result + "_" + itostr(valId); } return getValidSymbolName(Result); } // getID Wrappers - Ensure consistent usage... string getID(const Module *M) { return getID(M, "LLVMModule_"); } string getID(const Function *F) { return getID(F, "LLVMFunction_"); } string getID(const BasicBlock *BB) { return getID(BB, "LL", (".L_"+getID(BB->getParent())+"_").c_str()); } string getID(const GlobalVariable *GV) { return getID(GV, "LLVMGlobal_", ".G_"); } string getID(const Constant *CV) { return getID(CV, "LLVMConst_", ".C_"); } }; //===----------------------------------------------------------------------===// // SparcFunctionAsmPrinter Code //===----------------------------------------------------------------------===// struct SparcFunctionAsmPrinter : public MethodPass, public AsmPrinter { inline SparcFunctionAsmPrinter(std::ostream &os, const TargetMachine &t) : AsmPrinter(os, t) {} virtual bool doInitialization(Module *M) { startModule(M); return false; } virtual bool runOnMethod(Function *F) { startFunction(F); emitFunction(F); endFunction(F); return false; } virtual bool doFinalization(Module *M) { endModule(); return false; } void emitFunction(const Function *F); private : void emitBasicBlock(const BasicBlock *BB); void emitMachineInst(const MachineInstr *MI); unsigned int printOperands(const MachineInstr *MI, unsigned int opNum); void printOneOperand(const MachineOperand &Op); bool OpIsBranchTargetLabel(const MachineInstr *MI, unsigned int opNum); bool OpIsMemoryAddressBase(const MachineInstr *MI, unsigned int opNum); unsigned getOperandMask(unsigned Opcode) { switch (Opcode) { case SUBcc: return 1 << 3; // Remove CC argument case BA: return 1 << 0; // Remove Arg #0, which is always null or xcc default: return 0; // By default, don't hack operands... } } }; inline bool SparcFunctionAsmPrinter::OpIsBranchTargetLabel(const MachineInstr *MI, unsigned int opNum) { switch (MI->getOpCode()) { case JMPLCALL: case JMPLRET: return (opNum == 0); default: return false; } } inline bool SparcFunctionAsmPrinter::OpIsMemoryAddressBase(const MachineInstr *MI, unsigned int opNum) { if (Target.getInstrInfo().isLoad(MI->getOpCode())) return (opNum == 0); else if (Target.getInstrInfo().isStore(MI->getOpCode())) return (opNum == 1); else return false; } #define PrintOp1PlusOp2(Op1, Op2) \ printOneOperand(Op1); \ toAsm << "+"; \ printOneOperand(Op2); unsigned int SparcFunctionAsmPrinter::printOperands(const MachineInstr *MI, unsigned int opNum) { const MachineOperand& Op = MI->getOperand(opNum); if (OpIsBranchTargetLabel(MI, opNum)) { PrintOp1PlusOp2(Op, MI->getOperand(opNum+1)); return 2; } else if (OpIsMemoryAddressBase(MI, opNum)) { toAsm << "["; PrintOp1PlusOp2(Op, MI->getOperand(opNum+1)); toAsm << "]"; return 2; } else { printOneOperand(Op); return 1; } } void SparcFunctionAsmPrinter::printOneOperand(const MachineOperand &op) { switch (op.getOperandType()) { case MachineOperand::MO_VirtualRegister: case MachineOperand::MO_CCRegister: case MachineOperand::MO_MachineRegister: { int RegNum = (int)op.getAllocatedRegNum(); // better to print code with NULL registers than to die if (RegNum == Target.getRegInfo().getInvalidRegNum()) { toAsm << ""; } else { toAsm << "%" << Target.getRegInfo().getUnifiedRegName(RegNum); } break; } case MachineOperand::MO_PCRelativeDisp: { const Value *Val = op.getVRegValue(); if (!Val) toAsm << "\t<*NULL Value*>"; else if (const BasicBlock *BB = dyn_cast(Val)) toAsm << getID(BB); else if (const Function *M = dyn_cast(Val)) toAsm << getID(M); else if (const GlobalVariable *GV=dyn_cast(Val)) toAsm << getID(GV); else if (const Constant *CV = dyn_cast(Val)) toAsm << getID(CV); else toAsm << ""; break; } case MachineOperand::MO_SignExtendedImmed: case MachineOperand::MO_UnextendedImmed: toAsm << (long)op.getImmedValue(); break; default: toAsm << op; // use dump field break; } } void SparcFunctionAsmPrinter::emitMachineInst(const MachineInstr *MI) { unsigned Opcode = MI->getOpCode(); if (TargetInstrDescriptors[Opcode].iclass & M_DUMMY_PHI_FLAG) return; // IGNORE PHI NODES toAsm << "\t" << TargetInstrDescriptors[Opcode].opCodeString << "\t"; unsigned Mask = getOperandMask(Opcode); bool NeedComma = false; unsigned N = 1; for (unsigned OpNum = 0; OpNum < MI->getNumOperands(); OpNum += N) if (! ((1 << OpNum) & Mask)) { // Ignore this operand? if (NeedComma) toAsm << ", "; // Handle comma outputing NeedComma = true; N = printOperands(MI, OpNum); } else N = 1; toAsm << "\n"; } void SparcFunctionAsmPrinter::emitBasicBlock(const BasicBlock *BB) { // Emit a label for the basic block toAsm << getID(BB) << ":\n"; // Get the vector of machine instructions corresponding to this bb. const MachineCodeForBasicBlock &MIs = BB->getMachineInstrVec(); MachineCodeForBasicBlock::const_iterator MII = MIs.begin(), MIE = MIs.end(); // Loop over all of the instructions in the basic block... for (; MII != MIE; ++MII) emitMachineInst(*MII); toAsm << "\n"; // Seperate BB's with newlines } void SparcFunctionAsmPrinter::emitFunction(const Function *M) { string methName = getID(M); toAsm << "!****** Outputing Function: " << methName << " ******\n"; enterSection(AsmPrinter::Text); toAsm << "\t.align\t4\n\t.global\t" << methName << "\n"; //toAsm << "\t.type\t" << methName << ",#function\n"; toAsm << "\t.type\t" << methName << ", 2\n"; toAsm << methName << ":\n"; // Output code for all of the basic blocks in the function... for (Function::const_iterator I = M->begin(), E = M->end(); I != E; ++I) emitBasicBlock(*I); // Output a .size directive so the debugger knows the extents of the function toAsm << ".EndOf_" << methName << ":\n\t.size " << methName << ", .EndOf_" << methName << "-" << methName << "\n"; // Put some spaces between the functions toAsm << "\n\n"; } } // End anonymous namespace Pass *UltraSparc::getMethodAsmPrinterPass(PassManager &PM, std::ostream &Out) { return new SparcFunctionAsmPrinter(Out, *this); } //===----------------------------------------------------------------------===// // SparcFunctionAsmPrinter Code //===----------------------------------------------------------------------===// namespace { class SparcModuleAsmPrinter : public Pass, public AsmPrinter { public: SparcModuleAsmPrinter(std::ostream &os, TargetMachine &t) : AsmPrinter(os, t) {} virtual bool run(Module *M) { startModule(M); emitGlobalsAndConstants(M); endModule(); return false; } void emitGlobalsAndConstants(const Module *M); void printGlobalVariable(const GlobalVariable *GV); void printSingleConstant( const Constant* CV); void printConstantValueOnly(const Constant* CV); void printConstant( const Constant* CV, std::string valID = ""); static void FoldConstants(const Module *M, std::hash_set &moduleConstants); }; // Can we treat the specified array as a string? Only if it is an array of // ubytes or non-negative sbytes. // static bool isStringCompatible(ConstantArray *CPA) { const Type *ETy = cast(CPA->getType())->getElementType(); if (ETy == Type::UByteTy) return true; if (ETy != Type::SByteTy) return false; for (unsigned i = 0; i < CPA->getNumOperands(); ++i) if (cast(CPA->getOperand(i))->getValue() < 0) return false; return true; } // toOctal - Convert the low order bits of X into an octal letter static inline char toOctal(int X) { return (X&7)+'0'; } // getAsCString - Return the specified array as a C compatible string, only if // the predicate isStringCompatible is true. // static string getAsCString(ConstantArray *CPA) { assert(isStringCompatible(CPA) && "Array is not string compatible!"); string Result; const Type *ETy = cast(CPA->getType())->getElementType(); Result = "\""; for (unsigned i = 0; i < CPA->getNumOperands(); ++i) { unsigned char C = (ETy == Type::SByteTy) ? (unsigned char)cast(CPA->getOperand(i))->getValue() : (unsigned char)cast(CPA->getOperand(i))->getValue(); if (isprint(C)) { Result += C; } else { switch(C) { case '\a': Result += "\\a"; break; case '\b': Result += "\\b"; break; case '\f': Result += "\\f"; break; case '\n': Result += "\\n"; break; case '\r': Result += "\\r"; break; case '\t': Result += "\\t"; break; case '\v': Result += "\\v"; break; default: Result += '\\'; Result += toOctal(C >> 6); Result += toOctal(C >> 3); Result += toOctal(C >> 0); break; } } } Result += "\""; return Result; } inline bool ArrayTypeIsString(ArrayType* arrayType) { return (arrayType->getElementType() == Type::UByteTy || arrayType->getElementType() == Type::SByteTy); } inline const string TypeToDataDirective(const Type* type) { switch(type->getPrimitiveID()) { case Type::BoolTyID: case Type::UByteTyID: case Type::SByteTyID: return ".byte"; case Type::UShortTyID: case Type::ShortTyID: return ".half"; case Type::UIntTyID: case Type::IntTyID: return ".word"; case Type::ULongTyID: case Type::LongTyID: case Type::PointerTyID: return ".xword"; case Type::FloatTyID: return ".word"; case Type::DoubleTyID: return ".xword"; case Type::ArrayTyID: if (ArrayTypeIsString((ArrayType*) type)) return ".ascii"; else return ""; default: return ""; } } // Get the size of the constant for the given target. // If this is an unsized array, return 0. // inline unsigned int ConstantToSize(const Constant* CV, const TargetMachine& target) { if (ConstantArray* CPA = dyn_cast(CV)) { ArrayType *aty = cast(CPA->getType()); if (ArrayTypeIsString(aty)) return 1 + CPA->getNumOperands(); } return target.findOptimalStorageSize(CV->getType()); } // Align data larger than one L1 cache line on L1 cache line boundaries. // Align all smaller data on the next higher 2^x boundary (4, 8, ...). // inline unsigned int SizeToAlignment(unsigned int size, const TargetMachine& target) { unsigned short cacheLineSize = target.getCacheInfo().getCacheLineSize(1); if (size > (unsigned) cacheLineSize / 2) return cacheLineSize; else for (unsigned sz=1; /*no condition*/; sz *= 2) if (sz >= size) return sz; } // Get the size of the type and then use SizeToAlignment. // inline unsigned int TypeToAlignment(const Type* type, const TargetMachine& target) { return SizeToAlignment(target.findOptimalStorageSize(type), target); } // Get the size of the constant and then use SizeToAlignment. // Handles strings as a special case; inline unsigned int ConstantToAlignment(const Constant* CV, const TargetMachine& target) { if (ConstantArray* CPA = dyn_cast(CV)) if (ArrayTypeIsString(cast(CPA->getType()))) return SizeToAlignment(1 + CPA->getNumOperands(), target); return TypeToAlignment(CV->getType(), target); } // Print a single constant value. void SparcModuleAsmPrinter::printSingleConstant(const Constant* CV) { assert(CV->getType() != Type::VoidTy && CV->getType() != Type::TypeTy && CV->getType() != Type::LabelTy && "Unexpected type for Constant"); assert((!isa(CV) && ! isa(CV)) && "Aggregate types should be handled outside this function"); toAsm << "\t" << TypeToDataDirective(CV->getType()) << "\t"; if (CV->getType()->isPrimitiveType()) { if (CV->getType()->isFloatingPoint()) { // FP Constants are printed as integer constants to avoid losing // precision... double Val = cast(CV)->getValue(); if (CV->getType() == Type::FloatTy) { float FVal = (float)Val; char *ProxyPtr = (char*)&FVal; // Abide by C TBAA rules toAsm << *(unsigned int*)ProxyPtr; } else if (CV->getType() == Type::DoubleTy) { char *ProxyPtr = (char*)&Val; // Abide by C TBAA rules toAsm << *(uint64_t*)ProxyPtr; } else { assert(0 && "Unknown floating point type!"); } toAsm << "\t! " << CV->getType()->getDescription() << " value: " << Val << "\n"; } else { WriteAsOperand(toAsm, CV, false, false) << "\n"; } } else if (ConstantPointer* CPP = dyn_cast(CV)) { assert(CPP->isNullValue() && "Cannot yet print non-null pointer constants to assembly"); toAsm << "0\n"; } else if (isa(CV)) { assert(0 && "Cannot yet initialize pointer refs in assembly"); } else { assert(0 && "Unknown elementary type for constant"); } } // Print a constant value or values (it may be an aggregate). // Uses printSingleConstant() to print each individual value. void SparcModuleAsmPrinter::printConstantValueOnly(const Constant* CV) { ConstantArray *CPA = dyn_cast(CV); if (CPA && isStringCompatible(CPA)) { // print the string alone and return toAsm << "\t" << ".ascii" << "\t" << getAsCString(CPA) << "\n"; } else if (CPA) { // Not a string. Print the values in successive locations const std::vector &constValues = CPA->getValues(); for (unsigned i=1; i < constValues.size(); i++) this->printConstantValueOnly(cast(constValues[i].get())); } else if (ConstantStruct *CPS = dyn_cast(CV)) { // Print the fields in successive locations const std::vector& constValues = CPS->getValues(); for (unsigned i=1; i < constValues.size(); i++) this->printConstantValueOnly(cast(constValues[i].get())); } else this->printSingleConstant(CV); } // Print a constant (which may be an aggregate) prefixed by all the // appropriate directives. Uses printConstantValueOnly() to print the // value or values. void SparcModuleAsmPrinter::printConstant(const Constant* CV, string valID) { if (valID.length() == 0) valID = getID(CV); toAsm << "\t.align\t" << ConstantToAlignment(CV, Target) << "\n"; // Print .size and .type only if it is not a string. ConstantArray *CPA = dyn_cast(CV); if (CPA && isStringCompatible(CPA)) { // print it as a string and return toAsm << valID << ":\n"; toAsm << "\t" << ".ascii" << "\t" << getAsCString(CPA) << "\n"; return; } toAsm << "\t.type" << "\t" << valID << ",#object\n"; unsigned int constSize = ConstantToSize(CV, Target); if (constSize) toAsm << "\t.size" << "\t" << valID << "," << constSize << "\n"; toAsm << valID << ":\n"; printConstantValueOnly(CV); } void SparcModuleAsmPrinter::FoldConstants(const Module *M, std::hash_set &MC) { for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) if (!(*I)->isExternal()) { const std::hash_set &pool = MachineCodeForMethod::get(*I).getConstantPoolValues(); MC.insert(pool.begin(), pool.end()); } } void SparcModuleAsmPrinter::printGlobalVariable(const GlobalVariable* GV) { toAsm << "\t.global\t" << getID(GV) << "\n"; if (GV->hasInitializer()) printConstant(GV->getInitializer(), getID(GV)); else { toAsm << "\t.align\t" << TypeToAlignment(GV->getType()->getElementType(), Target) << "\n"; toAsm << "\t.type\t" << getID(GV) << ",#object\n"; toAsm << "\t.reserve\t" << getID(GV) << "," << Target.findOptimalStorageSize(GV->getType()->getElementType()) << "\n"; } } void SparcModuleAsmPrinter::emitGlobalsAndConstants(const Module *M) { // First, get the constants there were marked by the code generator for // inclusion in the assembly code data area and fold them all into a // single constant pool since there may be lots of duplicates. Also, // lets force these constants into the slot table so that we can get // unique names for unnamed constants also. // std::hash_set moduleConstants; FoldConstants(M, moduleConstants); // Now, emit the three data sections separately; the cost of I/O should // make up for the cost of extra passes over the globals list! // Section 1 : Read-only data section (implies initialized) enterSection(AsmPrinter::ReadOnlyData); for (Module::const_giterator GI=M->gbegin(), GE=M->gend(); GI != GE; ++GI) if ((*GI)->hasInitializer() && (*GI)->isConstant()) printGlobalVariable(*GI); for (std::hash_set::const_iterator I = moduleConstants.begin(), E = moduleConstants.end(); I != E; ++I) printConstant(*I); // Section 2 : Initialized read-write data section enterSection(AsmPrinter::InitRWData); for (Module::const_giterator GI=M->gbegin(), GE=M->gend(); GI != GE; ++GI) if ((*GI)->hasInitializer() && ! (*GI)->isConstant()) printGlobalVariable(*GI); // Section 3 : Uninitialized read-write data section enterSection(AsmPrinter::UninitRWData); for (Module::const_giterator GI=M->gbegin(), GE=M->gend(); GI != GE; ++GI) if (! (*GI)->hasInitializer()) printGlobalVariable(*GI); toAsm << "\n"; } } // End anonymous namespace Pass *UltraSparc::getModuleAsmPrinterPass(PassManager &PM, std::ostream &Out) { return new SparcModuleAsmPrinter(Out, *this); }