1 //===-- MipsSubtarget.cpp - Mips Subtarget Information --------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file implements the Mips specific subclass of TargetSubtargetInfo. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #define DEBUG_TYPE "mips-subtarget" 15 16 #include "MipsMachineFunction.h" 17 #include "MipsSubtarget.h" 18 #include "MipsTargetMachine.h" 19 #include "Mips.h" 20 #include "MipsRegisterInfo.h" 21 #include "llvm/IR/Attributes.h" 22 #include "llvm/IR/Function.h" 23 #include "llvm/Support/CommandLine.h" 24 #include "llvm/Support/Debug.h" 25 #include "llvm/Support/TargetRegistry.h" 26 #include "llvm/Support/raw_ostream.h" 27 28 #define GET_SUBTARGETINFO_TARGET_DESC 29 #define GET_SUBTARGETINFO_CTOR 30 #include "MipsGenSubtargetInfo.inc" 31 32 33 using namespace llvm; 34 35 // FIXME: Maybe this should be on by default when Mips16 is specified 36 // 37 static cl::opt<bool> Mixed16_32( 38 "mips-mixed-16-32", 39 cl::init(false), 40 cl::desc("Allow for a mixture of Mips16 " 41 "and Mips32 code in a single source file"), 42 cl::Hidden); 43 44 static cl::opt<bool> Mips_Os16( 45 "mips-os16", 46 cl::init(false), 47 cl::desc("Compile all functions that don' use " 48 "floating point as Mips 16"), 49 cl::Hidden); 50 51 static cl::opt<bool> 52 Mips16HardFloat("mips16-hard-float", cl::NotHidden, 53 cl::desc("MIPS: mips16 hard float enable."), 54 cl::init(false)); 55 56 void MipsSubtarget::anchor() { } 57 58 MipsSubtarget::MipsSubtarget(const std::string &TT, const std::string &CPU, 59 const std::string &FS, bool little, 60 Reloc::Model _RM, MipsTargetMachine *_TM) : 61 MipsGenSubtargetInfo(TT, CPU, FS), 62 MipsArchVersion(Mips32), MipsABI(UnknownABI), IsLittle(little), 63 IsSingleFloat(false), IsFP64bit(false), IsGP64bit(false), HasVFPU(false), 64 IsLinux(true), HasSEInReg(false), HasCondMov(false), HasSwap(false), 65 HasBitCount(false), HasFPIdx(false), 66 InMips16Mode(false), InMips16HardFloat(Mips16HardFloat), 67 InMicroMipsMode(false), HasDSP(false), HasDSPR2(false), 68 AllowMixed16_32(Mixed16_32 | Mips_Os16), Os16(Mips_Os16), HasMSA(false), 69 RM(_RM), OverrideMode(NoOverride), TM(_TM) 70 { 71 std::string CPUName = CPU; 72 if (CPUName.empty()) 73 CPUName = "mips32"; 74 75 // Parse features string. 76 ParseSubtargetFeatures(CPUName, FS); 77 78 PreviousInMips16Mode = InMips16Mode; 79 80 // Initialize scheduling itinerary for the specified CPU. 81 InstrItins = getInstrItineraryForCPU(CPUName); 82 83 // Set MipsABI if it hasn't been set yet. 84 if (MipsABI == UnknownABI) 85 MipsABI = hasMips64() ? N64 : O32; 86 87 // Check if Architecture and ABI are compatible. 88 assert(((!hasMips64() && (isABI_O32() || isABI_EABI())) || 89 (hasMips64() && (isABI_N32() || isABI_N64()))) && 90 "Invalid Arch & ABI pair."); 91 92 // Is the target system Linux ? 93 if (TT.find("linux") == std::string::npos) 94 IsLinux = false; 95 96 // Set UseSmallSection. 97 UseSmallSection = !IsLinux && (RM == Reloc::Static); 98 // set some subtarget specific features 99 if (inMips16Mode()) 100 HasBitCount=false; 101 } 102 103 bool 104 MipsSubtarget::enablePostRAScheduler(CodeGenOpt::Level OptLevel, 105 TargetSubtargetInfo::AntiDepBreakMode &Mode, 106 RegClassVector &CriticalPathRCs) const { 107 Mode = TargetSubtargetInfo::ANTIDEP_NONE; 108 CriticalPathRCs.clear(); 109 CriticalPathRCs.push_back(hasMips64() ? 110 &Mips::GPR64RegClass : &Mips::GPR32RegClass); 111 return OptLevel >= CodeGenOpt::Aggressive; 112 } 113 114 //FIXME: This logic for reseting the subtarget along with 115 // the helper classes can probably be simplified but there are a lot of 116 // cases so we will defer rewriting this to later. 117 // 118 void MipsSubtarget::resetSubtarget(MachineFunction *MF) { 119 bool ChangeToMips16 = false, ChangeToNoMips16 = false; 120 DEBUG(dbgs() << "resetSubtargetFeatures" << "\n"); 121 AttributeSet FnAttrs = MF->getFunction()->getAttributes(); 122 ChangeToMips16 = FnAttrs.hasAttribute(AttributeSet::FunctionIndex, 123 "mips16"); 124 ChangeToNoMips16 = FnAttrs.hasAttribute(AttributeSet::FunctionIndex, 125 "nomips16"); 126 assert (!(ChangeToMips16 & ChangeToNoMips16) && 127 "mips16 and nomips16 specified on the same function"); 128 if (ChangeToMips16) { 129 if (PreviousInMips16Mode) 130 return; 131 OverrideMode = Mips16Override; 132 PreviousInMips16Mode = true; 133 TM->setHelperClassesMips16(); 134 return; 135 } else if (ChangeToNoMips16) { 136 if (!PreviousInMips16Mode) 137 return; 138 OverrideMode = NoMips16Override; 139 PreviousInMips16Mode = false; 140 TM->setHelperClassesMipsSE(); 141 return; 142 } else { 143 if (OverrideMode == NoOverride) 144 return; 145 OverrideMode = NoOverride; 146 DEBUG(dbgs() << "back to default" << "\n"); 147 if (inMips16Mode() && !PreviousInMips16Mode) { 148 TM->setHelperClassesMips16(); 149 PreviousInMips16Mode = true; 150 } else if (!inMips16Mode() && PreviousInMips16Mode) { 151 TM->setHelperClassesMipsSE(); 152 PreviousInMips16Mode = false; 153 } 154 return; 155 } 156 } 157 158