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), 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 } 99 100 bool 101 MipsSubtarget::enablePostRAScheduler(CodeGenOpt::Level OptLevel, 102 TargetSubtargetInfo::AntiDepBreakMode &Mode, 103 RegClassVector &CriticalPathRCs) const { 104 Mode = TargetSubtargetInfo::ANTIDEP_NONE; 105 CriticalPathRCs.clear(); 106 CriticalPathRCs.push_back(hasMips64() ? 107 &Mips::GPR64RegClass : &Mips::GPR32RegClass); 108 return OptLevel >= CodeGenOpt::Aggressive; 109 } 110 111 //FIXME: This logic for reseting the subtarget along with 112 // the helper classes can probably be simplified but there are a lot of 113 // cases so we will defer rewriting this to later. 114 // 115 void MipsSubtarget::resetSubtarget(MachineFunction *MF) { 116 bool ChangeToMips16 = false, ChangeToNoMips16 = false; 117 DEBUG(dbgs() << "resetSubtargetFeatures" << "\n"); 118 AttributeSet FnAttrs = MF->getFunction()->getAttributes(); 119 ChangeToMips16 = FnAttrs.hasAttribute(AttributeSet::FunctionIndex, 120 "mips16"); 121 ChangeToNoMips16 = FnAttrs.hasAttribute(AttributeSet::FunctionIndex, 122 "nomips16"); 123 assert (!(ChangeToMips16 & ChangeToNoMips16) && 124 "mips16 and nomips16 specified on the same function"); 125 if (ChangeToMips16) { 126 if (PreviousInMips16Mode) 127 return; 128 OverrideMode = Mips16Override; 129 PreviousInMips16Mode = true; 130 TM->setHelperClassesMips16(); 131 return; 132 } else if (ChangeToNoMips16) { 133 if (!PreviousInMips16Mode) 134 return; 135 OverrideMode = NoMips16Override; 136 PreviousInMips16Mode = false; 137 TM->setHelperClassesMipsSE(); 138 return; 139 } else { 140 if (OverrideMode == NoOverride) 141 return; 142 OverrideMode = NoOverride; 143 DEBUG(dbgs() << "back to default" << "\n"); 144 if (inMips16Mode() && !PreviousInMips16Mode) { 145 TM->setHelperClassesMips16(); 146 PreviousInMips16Mode = true; 147 } else if (!inMips16Mode() && PreviousInMips16Mode) { 148 TM->setHelperClassesMipsSE(); 149 PreviousInMips16Mode = false; 150 } 151 return; 152 } 153 } 154 155