1 //===-- MipsSERegisterInfo.cpp - MIPS32/64 Register 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 contains the MIPS32/64 implementation of the TargetRegisterInfo 11 // class. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "MipsSERegisterInfo.h" 16 #include "Mips.h" 17 #include "MipsAnalyzeImmediate.h" 18 #include "MipsMachineFunction.h" 19 #include "MipsSEInstrInfo.h" 20 #include "MipsSubtarget.h" 21 #include "llvm/ADT/BitVector.h" 22 #include "llvm/ADT/STLExtras.h" 23 #include "llvm/CodeGen/MachineFrameInfo.h" 24 #include "llvm/CodeGen/MachineFunction.h" 25 #include "llvm/CodeGen/MachineInstrBuilder.h" 26 #include "llvm/CodeGen/MachineRegisterInfo.h" 27 #include "llvm/CodeGen/ValueTypes.h" 28 #include "llvm/DebugInfo.h" 29 #include "llvm/IR/Constants.h" 30 #include "llvm/IR/Function.h" 31 #include "llvm/IR/Type.h" 32 #include "llvm/Support/CommandLine.h" 33 #include "llvm/Support/Debug.h" 34 #include "llvm/Support/ErrorHandling.h" 35 #include "llvm/Support/raw_ostream.h" 36 #include "llvm/Target/TargetFrameLowering.h" 37 #include "llvm/Target/TargetInstrInfo.h" 38 #include "llvm/Target/TargetMachine.h" 39 #include "llvm/Target/TargetOptions.h" 40 41 using namespace llvm; 42 43 MipsSERegisterInfo::MipsSERegisterInfo(const MipsSubtarget &ST) 44 : MipsRegisterInfo(ST) {} 45 46 bool MipsSERegisterInfo:: 47 requiresRegisterScavenging(const MachineFunction &MF) const { 48 return true; 49 } 50 51 bool MipsSERegisterInfo:: 52 requiresFrameIndexScavenging(const MachineFunction &MF) const { 53 return true; 54 } 55 56 const TargetRegisterClass * 57 MipsSERegisterInfo::intRegClass(unsigned Size) const { 58 if (Size == 4) 59 return &Mips::GPR32RegClass; 60 61 assert(Size == 8); 62 return &Mips::GPR64RegClass; 63 } 64 65 void MipsSERegisterInfo::eliminateFI(MachineBasicBlock::iterator II, 66 unsigned OpNo, int FrameIndex, 67 uint64_t StackSize, 68 int64_t SPOffset) const { 69 MachineInstr &MI = *II; 70 MachineFunction &MF = *MI.getParent()->getParent(); 71 MachineFrameInfo *MFI = MF.getFrameInfo(); 72 MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>(); 73 74 const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo(); 75 int MinCSFI = 0; 76 int MaxCSFI = -1; 77 78 if (CSI.size()) { 79 MinCSFI = CSI[0].getFrameIdx(); 80 MaxCSFI = CSI[CSI.size() - 1].getFrameIdx(); 81 } 82 83 bool EhDataRegFI = MipsFI->isEhDataRegFI(FrameIndex); 84 85 // The following stack frame objects are always referenced relative to $sp: 86 // 1. Outgoing arguments. 87 // 2. Pointer to dynamically allocated stack space. 88 // 3. Locations for callee-saved registers. 89 // 4. Locations for eh data registers. 90 // Everything else is referenced relative to whatever register 91 // getFrameRegister() returns. 92 unsigned FrameReg; 93 94 if ((FrameIndex >= MinCSFI && FrameIndex <= MaxCSFI) || EhDataRegFI) 95 FrameReg = Subtarget.isABI_N64() ? Mips::SP_64 : Mips::SP; 96 else 97 FrameReg = getFrameRegister(MF); 98 99 // Calculate final offset. 100 // - There is no need to change the offset if the frame object is one of the 101 // following: an outgoing argument, pointer to a dynamically allocated 102 // stack space or a $gp restore location, 103 // - If the frame object is any of the following, its offset must be adjusted 104 // by adding the size of the stack: 105 // incoming argument, callee-saved register location or local variable. 106 bool IsKill = false; 107 int64_t Offset; 108 109 Offset = SPOffset + (int64_t)StackSize; 110 Offset += MI.getOperand(OpNo + 1).getImm(); 111 112 DEBUG(errs() << "Offset : " << Offset << "\n" << "<--------->\n"); 113 114 // If MI is not a debug value, make sure Offset fits in the 16-bit immediate 115 // field. 116 if (!MI.isDebugValue() && !isInt<16>(Offset)) { 117 MachineBasicBlock &MBB = *MI.getParent(); 118 DebugLoc DL = II->getDebugLoc(); 119 unsigned ADDu = Subtarget.isABI_N64() ? Mips::DADDu : Mips::ADDu; 120 unsigned NewImm; 121 const MipsSEInstrInfo &TII = 122 *static_cast<const MipsSEInstrInfo*>( 123 MBB.getParent()->getTarget().getInstrInfo()); 124 unsigned Reg = TII.loadImmediate(Offset, MBB, II, DL, &NewImm); 125 BuildMI(MBB, II, DL, TII.get(ADDu), Reg).addReg(FrameReg) 126 .addReg(Reg, RegState::Kill); 127 128 FrameReg = Reg; 129 Offset = SignExtend64<16>(NewImm); 130 IsKill = true; 131 } 132 133 MI.getOperand(OpNo).ChangeToRegister(FrameReg, false, false, IsKill); 134 MI.getOperand(OpNo + 1).ChangeToImmediate(Offset); 135 } 136