llvm-6502/lib/Target/PIC16/PIC16InstrInfo.cpp
2009-10-27 17:40:24 +00:00

239 lines
9.2 KiB
C++

//===- PIC16InstrInfo.cpp - PIC16 Instruction Information -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the PIC16 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "PIC16.h"
#include "PIC16ABINames.h"
#include "PIC16InstrInfo.h"
#include "PIC16TargetMachine.h"
#include "PIC16GenInstrInfo.inc"
#include "llvm/Function.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Support/ErrorHandling.h"
#include <cstdio>
using namespace llvm;
// FIXME: Add the subtarget support on this constructor.
PIC16InstrInfo::PIC16InstrInfo(PIC16TargetMachine &tm)
: TargetInstrInfoImpl(PIC16Insts, array_lengthof(PIC16Insts)),
TM(tm),
RegInfo(*this, *TM.getSubtargetImpl()) {}
/// isStoreToStackSlot - If the specified machine instruction is a direct
/// store to a stack slot, return the virtual or physical register number of
/// the source reg along with the FrameIndex of the loaded stack slot.
/// If not, return 0. This predicate must return 0 if the instruction has
/// any side effects other than storing to the stack slot.
unsigned PIC16InstrInfo::isStoreToStackSlot(const MachineInstr *MI,
int &FrameIndex) const {
if (MI->getOpcode() == PIC16::movwf
&& MI->getOperand(0).isReg()
&& MI->getOperand(1).isSymbol()) {
FrameIndex = MI->getOperand(1).getIndex();
return MI->getOperand(0).getReg();
}
return 0;
}
/// isLoadFromStackSlot - If the specified machine instruction is a direct
/// load from a stack slot, return the virtual or physical register number of
/// the dest reg along with the FrameIndex of the stack slot.
/// If not, return 0. This predicate must return 0 if the instruction has
/// any side effects other than storing to the stack slot.
unsigned PIC16InstrInfo::isLoadFromStackSlot(const MachineInstr *MI,
int &FrameIndex) const {
if (MI->getOpcode() == PIC16::movf
&& MI->getOperand(0).isReg()
&& MI->getOperand(1).isSymbol()) {
FrameIndex = MI->getOperand(1).getIndex();
return MI->getOperand(0).getReg();
}
return 0;
}
void PIC16InstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned SrcReg, bool isKill, int FI,
const TargetRegisterClass *RC) const {
PIC16TargetLowering *PTLI = TM.getTargetLowering();
DebugLoc DL = DebugLoc::getUnknownLoc();
if (I != MBB.end()) DL = I->getDebugLoc();
const Function *Func = MBB.getParent()->getFunction();
const std::string FuncName = Func->getName();
const char *tmpName = createESName(PAN::getTempdataLabel(FuncName));
// On the order of operands here: think "movwf SrcReg, tmp_slot, offset".
if (RC == PIC16::GPRRegisterClass) {
//MachineFunction &MF = *MBB.getParent();
//MachineRegisterInfo &RI = MF.getRegInfo();
BuildMI(MBB, I, DL, get(PIC16::movwf))
.addReg(SrcReg, getKillRegState(isKill))
.addImm(PTLI->GetTmpOffsetForFI(FI, 1))
.addExternalSymbol(tmpName)
.addImm(1); // Emit banksel for it.
}
else if (RC == PIC16::FSR16RegisterClass) {
// This is a 16-bit register and the frameindex given by llvm is of
// size two here. Break this index N into two zero based indexes and
// put one into the map. The second one is always obtained by adding 1
// to the first zero based index. In fact it is going to use 3 slots
// as saving FSRs corrupts W also and hence we need to save/restore W also.
unsigned opcode = (SrcReg == PIC16::FSR0) ? PIC16::save_fsr0
: PIC16::save_fsr1;
BuildMI(MBB, I, DL, get(opcode))
.addReg(SrcReg, getKillRegState(isKill))
.addImm(PTLI->GetTmpOffsetForFI(FI, 3))
.addExternalSymbol(tmpName)
.addImm(1); // Emit banksel for it.
}
else
llvm_unreachable("Can't store this register to stack slot");
}
void PIC16InstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned DestReg, int FI,
const TargetRegisterClass *RC) const {
PIC16TargetLowering *PTLI = TM.getTargetLowering();
DebugLoc DL = DebugLoc::getUnknownLoc();
if (I != MBB.end()) DL = I->getDebugLoc();
const Function *Func = MBB.getParent()->getFunction();
const std::string FuncName = Func->getName();
const char *tmpName = createESName(PAN::getTempdataLabel(FuncName));
// On the order of operands here: think "movf FrameIndex, W".
if (RC == PIC16::GPRRegisterClass) {
//MachineFunction &MF = *MBB.getParent();
//MachineRegisterInfo &RI = MF.getRegInfo();
BuildMI(MBB, I, DL, get(PIC16::movf), DestReg)
.addImm(PTLI->GetTmpOffsetForFI(FI, 1))
.addExternalSymbol(tmpName)
.addImm(1); // Emit banksel for it.
}
else if (RC == PIC16::FSR16RegisterClass) {
// This is a 16-bit register and the frameindex given by llvm is of
// size two here. Break this index N into two zero based indexes and
// put one into the map. The second one is always obtained by adding 1
// to the first zero based index. In fact it is going to use 3 slots
// as saving FSRs corrupts W also and hence we need to save/restore W also.
unsigned opcode = (DestReg == PIC16::FSR0) ? PIC16::restore_fsr0
: PIC16::restore_fsr1;
BuildMI(MBB, I, DL, get(opcode), DestReg)
.addImm(PTLI->GetTmpOffsetForFI(FI, 3))
.addExternalSymbol(tmpName)
.addImm(1); // Emit banksel for it.
}
else
llvm_unreachable("Can't load this register from stack slot");
}
bool PIC16InstrInfo::copyRegToReg (MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned DestReg, unsigned SrcReg,
const TargetRegisterClass *DestRC,
const TargetRegisterClass *SrcRC) const {
DebugLoc DL = DebugLoc::getUnknownLoc();
if (I != MBB.end()) DL = I->getDebugLoc();
if (DestRC == PIC16::FSR16RegisterClass) {
BuildMI(MBB, I, DL, get(PIC16::copy_fsr), DestReg).addReg(SrcReg);
return true;
}
if (DestRC == PIC16::GPRRegisterClass) {
BuildMI(MBB, I, DL, get(PIC16::copy_w), DestReg).addReg(SrcReg);
return true;
}
// Not yet supported.
return false;
}
bool PIC16InstrInfo::isMoveInstr(const MachineInstr &MI,
unsigned &SrcReg, unsigned &DestReg,
unsigned &SrcSubIdx, unsigned &DstSubIdx) const {
SrcSubIdx = DstSubIdx = 0; // No sub-registers.
if (MI.getOpcode() == PIC16::copy_fsr
|| MI.getOpcode() == PIC16::copy_w) {
DestReg = MI.getOperand(0).getReg();
SrcReg = MI.getOperand(1).getReg();
return true;
}
return false;
}
/// InsertBranch - Insert a branch into the end of the specified
/// MachineBasicBlock. This operands to this method are the same as those
/// returned by AnalyzeBranch. This is invoked in cases where AnalyzeBranch
/// returns success and when an unconditional branch (TBB is non-null, FBB is
/// null, Cond is empty) needs to be inserted. It returns the number of
/// instructions inserted.
unsigned PIC16InstrInfo::
InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
const SmallVectorImpl<MachineOperand> &Cond) const {
// Shouldn't be a fall through.
assert(TBB && "InsertBranch must not be told to insert a fallthrough");
if (FBB == 0) { // One way branch.
if (Cond.empty()) {
// Unconditional branch?
DebugLoc dl = DebugLoc::getUnknownLoc();
BuildMI(&MBB, dl, get(PIC16::br_uncond)).addMBB(TBB);
}
return 1;
}
// FIXME: If the there are some conditions specified then conditional branch
// should be generated.
// For the time being no instruction is being generated therefore
// returning NULL.
return 0;
}
bool PIC16InstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
SmallVectorImpl<MachineOperand> &Cond,
bool AllowModify) const {
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin())
return true;
// Get the terminator instruction.
--I;
// Handle unconditional branches. If the unconditional branch's target is
// successor basic block then remove the unconditional branch.
if (I->getOpcode() == PIC16::br_uncond && AllowModify) {
if (MBB.isLayoutSuccessor(I->getOperand(0).getMBB())) {
TBB = 0;
I->eraseFromParent();
}
}
return true;
}