1 //===-- MSP430RegisterInfo.cpp - MSP430 Register Information --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the MSP430 implementation of the TargetRegisterInfo class.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "msp430-reg-info"
16 #include "MSP430RegisterInfo.h"
18 #include "MSP430MachineFunctionInfo.h"
19 #include "MSP430TargetMachine.h"
20 #include "llvm/ADT/BitVector.h"
21 #include "llvm/CodeGen/MachineFrameInfo.h"
22 #include "llvm/CodeGen/MachineFunction.h"
23 #include "llvm/CodeGen/MachineInstrBuilder.h"
24 #include "llvm/IR/Function.h"
25 #include "llvm/Support/ErrorHandling.h"
26 #include "llvm/Target/TargetMachine.h"
27 #include "llvm/Target/TargetOptions.h"
29 #define GET_REGINFO_TARGET_DESC
30 #include "MSP430GenRegisterInfo.inc"
34 // FIXME: Provide proper call frame setup / destroy opcodes.
35 MSP430RegisterInfo::MSP430RegisterInfo(MSP430TargetMachine &tm)
36 : MSP430GenRegisterInfo(MSP430::PCW), TM(tm) {
37 StackAlign = TM.getFrameLowering()->getStackAlignment();
41 MSP430RegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
42 const TargetFrameLowering *TFI = MF->getTarget().getFrameLowering();
43 const Function* F = MF->getFunction();
44 static const uint16_t CalleeSavedRegs[] = {
45 MSP430::FPW, MSP430::R5W, MSP430::R6W, MSP430::R7W,
46 MSP430::R8W, MSP430::R9W, MSP430::R10W, MSP430::R11W,
49 static const uint16_t CalleeSavedRegsFP[] = {
50 MSP430::R5W, MSP430::R6W, MSP430::R7W,
51 MSP430::R8W, MSP430::R9W, MSP430::R10W, MSP430::R11W,
54 static const uint16_t CalleeSavedRegsIntr[] = {
55 MSP430::FPW, MSP430::R5W, MSP430::R6W, MSP430::R7W,
56 MSP430::R8W, MSP430::R9W, MSP430::R10W, MSP430::R11W,
57 MSP430::R12W, MSP430::R13W, MSP430::R14W, MSP430::R15W,
60 static const uint16_t CalleeSavedRegsIntrFP[] = {
61 MSP430::R5W, MSP430::R6W, MSP430::R7W,
62 MSP430::R8W, MSP430::R9W, MSP430::R10W, MSP430::R11W,
63 MSP430::R12W, MSP430::R13W, MSP430::R14W, MSP430::R15W,
68 return (F->getCallingConv() == CallingConv::MSP430_INTR ?
69 CalleeSavedRegsIntrFP : CalleeSavedRegsFP);
71 return (F->getCallingConv() == CallingConv::MSP430_INTR ?
72 CalleeSavedRegsIntr : CalleeSavedRegs);
76 BitVector MSP430RegisterInfo::getReservedRegs(const MachineFunction &MF) const {
77 BitVector Reserved(getNumRegs());
78 const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
80 // Mark 4 special registers with subregisters as reserved.
81 Reserved.set(MSP430::PCB);
82 Reserved.set(MSP430::SPB);
83 Reserved.set(MSP430::SRB);
84 Reserved.set(MSP430::CGB);
85 Reserved.set(MSP430::PCW);
86 Reserved.set(MSP430::SPW);
87 Reserved.set(MSP430::SRW);
88 Reserved.set(MSP430::CGW);
90 // Mark frame pointer as reserved if needed.
92 Reserved.set(MSP430::FPW);
97 const TargetRegisterClass *
98 MSP430RegisterInfo::getPointerRegClass(const MachineFunction &MF, unsigned Kind)
100 return &MSP430::GR16RegClass;
104 MSP430RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
105 int SPAdj, unsigned FIOperandNum,
106 RegScavenger *RS) const {
107 assert(SPAdj == 0 && "Unexpected");
109 MachineInstr &MI = *II;
110 MachineBasicBlock &MBB = *MI.getParent();
111 MachineFunction &MF = *MBB.getParent();
112 const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
113 DebugLoc dl = MI.getDebugLoc();
114 int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
116 unsigned BasePtr = (TFI->hasFP(MF) ? MSP430::FPW : MSP430::SPW);
117 int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex);
123 Offset += MF.getFrameInfo()->getStackSize();
125 Offset += 2; // Skip the saved FPW
127 // Fold imm into offset
128 Offset += MI.getOperand(FIOperandNum + 1).getImm();
130 if (MI.getOpcode() == MSP430::ADD16ri) {
131 // This is actually "load effective address" of the stack slot
132 // instruction. We have only two-address instructions, thus we need to
133 // expand it into mov + add
134 const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo();
136 MI.setDesc(TII.get(MSP430::MOV16rr));
137 MI.getOperand(FIOperandNum).ChangeToRegister(BasePtr, false);
142 // We need to materialize the offset via add instruction.
143 unsigned DstReg = MI.getOperand(0).getReg();
145 BuildMI(MBB, llvm::next(II), dl, TII.get(MSP430::SUB16ri), DstReg)
146 .addReg(DstReg).addImm(-Offset);
148 BuildMI(MBB, llvm::next(II), dl, TII.get(MSP430::ADD16ri), DstReg)
149 .addReg(DstReg).addImm(Offset);
154 MI.getOperand(FIOperandNum).ChangeToRegister(BasePtr, false);
155 MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset);
158 unsigned MSP430RegisterInfo::getFrameRegister(const MachineFunction &MF) const {
159 const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
161 return TFI->hasFP(MF) ? MSP430::FPW : MSP430::SPW;