1 //===-- Mips16RegisterInfo.cpp - MIPS16 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 MIPS16 implementation of the TargetRegisterInfo class. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "Mips16RegisterInfo.h" 15 #include "Mips.h" 16 #include "MipsAnalyzeImmediate.h" 17 #include "MipsInstrInfo.h" 18 #include "MipsSubtarget.h" 19 #include "MipsMachineFunction.h" 20 #include "llvm/Constants.h" 21 #include "llvm/DebugInfo.h" 22 #include "llvm/Type.h" 23 #include "llvm/Function.h" 24 #include "llvm/CodeGen/ValueTypes.h" 25 #include "llvm/CodeGen/MachineInstrBuilder.h" 26 #include "llvm/CodeGen/MachineFunction.h" 27 #include "llvm/CodeGen/MachineFrameInfo.h" 28 #include "llvm/Target/TargetFrameLowering.h" 29 #include "llvm/Target/TargetMachine.h" 30 #include "llvm/Target/TargetOptions.h" 31 #include "llvm/Target/TargetInstrInfo.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/ADT/BitVector.h" 37 #include "llvm/ADT/STLExtras.h" 38 39 using namespace llvm; 40 41 Mips16RegisterInfo::Mips16RegisterInfo(const MipsSubtarget &ST) 42 : MipsRegisterInfo(ST) {} 43 44 // This function eliminate ADJCALLSTACKDOWN, 45 // ADJCALLSTACKUP pseudo instructions 46 void Mips16RegisterInfo:: 47 eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB, 48 MachineBasicBlock::iterator I) const { 49 // Simply discard ADJCALLSTACKDOWN, ADJCALLSTACKUP instructions. 50 MBB.erase(I); 51 } 52 53 void Mips16RegisterInfo::eliminateFI(MachineBasicBlock::iterator II, 54 unsigned OpNo, int FrameIndex, 55 uint64_t StackSize, 56 int64_t SPOffset) const { 57 MachineInstr &MI = *II; 58 MachineFunction &MF = *MI.getParent()->getParent(); 59 MachineFrameInfo *MFI = MF.getFrameInfo(); 60 61 const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo(); 62 int MinCSFI = 0; 63 int MaxCSFI = -1; 64 65 if (CSI.size()) { 66 MinCSFI = CSI[0].getFrameIdx(); 67 MaxCSFI = CSI[CSI.size() - 1].getFrameIdx(); 68 } 69 70 // The following stack frame objects are always 71 // referenced relative to $sp: 72 // 1. Outgoing arguments. 73 // 2. Pointer to dynamically allocated stack space. 74 // 3. Locations for callee-saved registers. 75 // Everything else is referenced relative to whatever register 76 // getFrameRegister() returns. 77 unsigned FrameReg; 78 79 if (FrameIndex >= MinCSFI && FrameIndex <= MaxCSFI) 80 FrameReg = Subtarget.isABI_N64() ? Mips::SP_64 : Mips::SP; 81 else 82 FrameReg = getFrameRegister(MF); 83 84 // Calculate final offset. 85 // - There is no need to change the offset if the frame object 86 // is one of the 87 // following: an outgoing argument, pointer to a dynamically allocated 88 // stack space or a $gp restore location, 89 // - If the frame object is any of the following, 90 // its offset must be adjusted 91 // by adding the size of the stack: 92 // incoming argument, callee-saved register location or local variable. 93 int64_t Offset; 94 95 Offset = SPOffset + (int64_t)StackSize; 96 Offset += MI.getOperand(OpNo + 1).getImm(); 97 98 DEBUG(errs() << "Offset : " << Offset << "\n" << "<--------->\n"); 99 100 MI.getOperand(OpNo).ChangeToRegister(FrameReg, false); 101 MI.getOperand(OpNo + 1).ChangeToImmediate(Offset); 102 103 104 } 105