1 //===-- TargetMachine.cpp - General Target Information ---------------------==// 2 // 3 // This file describes the general parts of a Target machine. 4 // This file also implements MachineInstrInfo and MachineCacheInfo. 5 // 6 //===----------------------------------------------------------------------===// 7 8 #include "llvm/Target/TargetMachine.h" 9 #include "llvm/Target/MachineInstrInfo.h" 10 #include "llvm/Target/MachineCacheInfo.h" 11 #include "llvm/DerivedTypes.h" 12 13 //--------------------------------------------------------------------------- 14 // class TargetMachine 15 // 16 // Purpose: 17 // Machine description. 18 // 19 //--------------------------------------------------------------------------- 20 21 22 // function TargetMachine::findOptimalStorageSize 23 // 24 // Purpose: 25 // This default implementation assumes that all sub-word data items use 26 // space equal to optSizeForSubWordData, and all other primitive data 27 // items use space according to the type. 28 // 29 unsigned int 30 TargetMachine::findOptimalStorageSize(const Type* ty) const 31 { 32 switch(ty->getPrimitiveID()) 33 { 34 case Type::BoolTyID: 35 case Type::UByteTyID: 36 case Type::SByteTyID: 37 case Type::UShortTyID: 38 case Type::ShortTyID: 39 return optSizeForSubWordData; 40 41 default: 42 return DataLayout.getTypeSize(ty); 43 } 44 } 45 46 47 //--------------------------------------------------------------------------- 48 // class MachineInstructionInfo 49 // Interface to description of machine instructions 50 //--------------------------------------------------------------------------- 51 52 53 /*ctor*/ 54 MachineInstrInfo::MachineInstrInfo(const TargetMachine& tgt, 55 const MachineInstrDescriptor* _desc, 56 unsigned int _descSize, 57 unsigned int _numRealOpCodes) 58 : target(tgt), 59 desc(_desc), descSize(_descSize), numRealOpCodes(_numRealOpCodes) 60 { 61 // FIXME: TargetInstrDescriptors should not be global 62 assert(TargetInstrDescriptors == NULL && desc != NULL); 63 TargetInstrDescriptors = desc; // initialize global variable 64 } 65 66 67 MachineInstrInfo::~MachineInstrInfo() 68 { 69 TargetInstrDescriptors = NULL; // reset global variable 70 } 71 72 73 bool 74 MachineInstrInfo::constantFitsInImmedField(MachineOpCode opCode, 75 int64_t intValue) const 76 { 77 // First, check if opCode has an immed field. 78 bool isSignExtended; 79 uint64_t maxImmedValue = maxImmedConstant(opCode, isSignExtended); 80 if (maxImmedValue != 0) 81 { 82 // Now check if the constant fits 83 if (intValue <= (int64_t) maxImmedValue && 84 intValue >= -((int64_t) maxImmedValue+1)) 85 return true; 86 } 87 88 return false; 89 } 90 91 92 //--------------------------------------------------------------------------- 93 // class MachineCacheInfo 94 // 95 // Purpose: 96 // Describes properties of the target cache architecture. 97 //--------------------------------------------------------------------------- 98 99 /*ctor*/ 100 MachineCacheInfo::MachineCacheInfo(const TargetMachine& tgt) 101 : target(tgt) 102 { 103 Initialize(); 104 } 105 106 void 107 MachineCacheInfo::Initialize() 108 { 109 numLevels = 2; 110 cacheLineSizes.push_back(16); cacheLineSizes.push_back(32); 111 cacheSizes.push_back(1 << 15); cacheSizes.push_back(1 << 20); 112 cacheAssoc.push_back(1); cacheAssoc.push_back(4); 113 } 114