//===-- XCoreRegisterInfo.cpp - XCore Register 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 XCore implementation of the MRegisterInfo class.
//
//===----------------------------------------------------------------------===//
#include "XCoreRegisterInfo.h"
#include "XCore.h"
#include "XCoreInstrInfo.h"
#include "XCoreMachineFunctionInfo.h"
#include "XCoreSubtarget.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterScavenging.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
#define DEBUG_TYPE "xcore-reg-info"
#define GET_REGINFO_TARGET_DESC
#include "XCoreGenRegisterInfo.inc"
XCoreRegisterInfo::XCoreRegisterInfo()
: XCoreGenRegisterInfo(XCore::LR) {
}
// helper functions
static inline bool isImmUs(unsigned val) {
return val <= 11;
}
static inline bool isImmU6(unsigned val) {
return val < (1 << 6);
}
static inline bool isImmU16(unsigned val) {
return val < (1 << 16);
}
static void InsertFPImmInst(MachineBasicBlock::iterator II,
const XCoreInstrInfo &TII,
unsigned Reg, unsigned FrameReg, int Offset ) {
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
DebugLoc dl = MI.getDebugLoc();
switch (MI.getOpcode()) {
case XCore::LDWFI:
BuildMI(MBB, II, dl, TII.get(XCore::LDW_2rus), Reg)
.addReg(FrameReg)
.addImm(Offset)
.addMemOperand(*MI.memoperands_begin());
break;
case XCore::STWFI:
BuildMI(MBB, II, dl, TII.get(XCore::STW_2rus))
.addReg(Reg, getKillRegState(MI.getOperand(0).isKill()))
.addReg(FrameReg)
.addImm(Offset)
.addMemOperand(*MI.memoperands_begin());
break;
case XCore::LDAWFI:
BuildMI(MBB, II, dl, TII.get(XCore::LDAWF_l2rus), Reg)
.addReg(FrameReg)
.addImm(Offset);
break;
default:
llvm_unreachable("Unexpected Opcode");
}
}
static void InsertFPConstInst(MachineBasicBlock::iterator II,
const XCoreInstrInfo &TII,
unsigned Reg, unsigned FrameReg,
int Offset, RegScavenger *RS ) {
assert(RS && "requiresRegisterScavenging failed");
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
DebugLoc dl = MI.getDebugLoc();
unsigned ScratchOffset = RS->scavengeRegister(&XCore::GRRegsRegClass, II, 0);
RS->setRegUsed(ScratchOffset);
TII.loadImmediate(MBB, II, ScratchOffset, Offset);
switch (MI.getOpcode()) {
case XCore::LDWFI:
BuildMI(MBB, II, dl, TII.get(XCore::LDW_3r), Reg)
.addReg(FrameReg)
.addReg(ScratchOffset, RegState::Kill)
.addMemOperand(*MI.memoperands_begin());
break;
case XCore::STWFI:
BuildMI(MBB, II, dl, TII.get(XCore::STW_l3r))
.addReg(Reg, getKillRegState(MI.getOperand(0).isKill()))
.addReg(FrameReg)
.addReg(ScratchOffset, RegState::Kill)
.addMemOperand(*MI.memoperands_begin());
break;
case XCore::LDAWFI:
BuildMI(MBB, II, dl, TII.get(XCore::LDAWF_l3r), Reg)
.addReg(FrameReg)
.addReg(ScratchOffset, RegState::Kill);
break;
default:
llvm_unreachable("Unexpected Opcode");
}
}
static void InsertSPImmInst(MachineBasicBlock::iterator II,
const XCoreInstrInfo &TII,
unsigned Reg, int Offset) {
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
DebugLoc dl = MI.getDebugLoc();
bool isU6 = isImmU6(Offset);
switch (MI.getOpcode()) {
int NewOpcode;
case XCore::LDWFI:
NewOpcode = (isU6) ? XCore::LDWSP_ru6 : XCore::LDWSP_lru6;
BuildMI(MBB, II, dl, TII.get(NewOpcode), Reg)
.addImm(Offset)
.addMemOperand(*MI.memoperands_begin());
break;
case XCore::STWFI:
NewOpcode = (isU6) ? XCore::STWSP_ru6 : XCore::STWSP_lru6;
BuildMI(MBB, II, dl, TII.get(NewOpcode))
.addReg(Reg, getKillRegState(MI.getOperand(0).isKill()))
.addImm(Offset)
.addMemOperand(*MI.memoperands_begin());
break;
case XCore::LDAWFI:
NewOpcode = (isU6) ? XCore::LDAWSP_ru6 : XCore::LDAWSP_lru6;
BuildMI(MBB, II, dl, TII.get(NewOpcode), Reg)
.addImm(Offset);
break;
default:
llvm_unreachable("Unexpected Opcode");
}
}
static void InsertSPConstInst(MachineBasicBlock::iterator II,
const XCoreInstrInfo &TII,
unsigned Reg, int Offset, RegScavenger *RS ) {
assert(RS && "requiresRegisterScavenging failed");
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
DebugLoc dl = MI.getDebugLoc();
unsigned OpCode = MI.getOpcode();
unsigned ScratchBase;
if (OpCode==XCore::STWFI) {
ScratchBase = RS->scavengeRegister(&XCore::GRRegsRegClass, II, 0);
RS->setRegUsed(ScratchBase);
} else
ScratchBase = Reg;
BuildMI(MBB, II, dl, TII.get(XCore::LDAWSP_ru6), ScratchBase).addImm(0);
unsigned ScratchOffset = RS->scavengeRegister(&XCore::GRRegsRegClass, II, 0);
RS->setRegUsed(ScratchOffset);
TII.loadImmediate(MBB, II, ScratchOffset, Offset);
switch (OpCode) {
case XCore::LDWFI:
BuildMI(MBB, II, dl, TII.get(XCore::LDW_3r), Reg)
.addReg(ScratchBase, RegState::Kill)
.addReg(ScratchOffset, RegState::Kill)
.addMemOperand(*MI.memoperands_begin());
break;
case XCore::STWFI:
BuildMI(MBB, II, dl, TII.get(XCore::STW_l3r))
.addReg(Reg, getKillRegState(MI.getOperand(0).isKill()))
.addReg(ScratchBase, RegState::Kill)
.addReg(ScratchOffset, RegState::Kill)
.addMemOperand(*MI.memoperands_begin());
break;
case XCore::LDAWFI:
BuildMI(MBB, II, dl, TII.get(XCore::LDAWF_l3r), Reg)
.addReg(ScratchBase, RegState::Kill)
.addReg(ScratchOffset, RegState::Kill);
break;
default:
llvm_unreachable("Unexpected Opcode");
}
}
bool XCoreRegisterInfo::needsFrameMoves(const MachineFunction &MF) {
return MF.getMMI().hasDebugInfo() ||
MF.getFunction()->needsUnwindTableEntry();
}
const MCPhysReg *
XCoreRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
// The callee saved registers LR & FP are explicitly handled during
// emitPrologue & emitEpilogue and related functions.
static const MCPhysReg CalleeSavedRegs[] = {
XCore::R4, XCore::R5, XCore::R6, XCore::R7,
XCore::R8, XCore::R9, XCore::R10,
0
};
static const MCPhysReg CalleeSavedRegsFP[] = {
XCore::R4, XCore::R5, XCore::R6, XCore::R7,
XCore::R8, XCore::R9,
0
};
const TargetFrameLowering *TFI = MF->getSubtarget().getFrameLowering();
if (TFI->hasFP(*MF))
return CalleeSavedRegsFP;
return CalleeSavedRegs;
}
BitVector XCoreRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
BitVector Reserved(getNumRegs());
const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
Reserved.set(XCore::CP);
Reserved.set(XCore::DP);
Reserved.set(XCore::SP);
Reserved.set(XCore::LR);
if (TFI->hasFP(MF)) {
Reserved.set(XCore::R10);
}
return Reserved;
}
bool
XCoreRegisterInfo::requiresRegisterScavenging(const MachineFunction &MF) const {
return true;
}
bool
XCoreRegisterInfo::trackLivenessAfterRegAlloc(const MachineFunction &MF) const {
return true;
}
bool
XCoreRegisterInfo::useFPForScavengingIndex(const MachineFunction &MF) const {
return false;
}
void
XCoreRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
int SPAdj, unsigned FIOperandNum,
RegScavenger *RS) const {
assert(SPAdj == 0 && "Unexpected");
MachineInstr &MI = *II;
MachineOperand &FrameOp = MI.getOperand(FIOperandNum);
int FrameIndex = FrameOp.getIndex();
MachineFunction &MF = *MI.getParent()->getParent();
const XCoreInstrInfo &TII =
*static_cast<const XCoreInstrInfo *>(MF.getSubtarget().getInstrInfo());
const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex);
int StackSize = MF.getFrameInfo()->getStackSize();
#ifndef NDEBUG
DEBUG(errs() << "\nFunction : "
<< MF.getName() << "\n");
DEBUG(errs() << "<--------->\n");
DEBUG(MI.print(errs()));
DEBUG(errs() << "FrameIndex : " << FrameIndex << "\n");
DEBUG(errs() << "FrameOffset : " << Offset << "\n");
DEBUG(errs() << "StackSize : " << StackSize << "\n");
#endif
Offset += StackSize;
unsigned FrameReg = getFrameRegister(MF);
// Special handling of DBG_VALUE instructions.
if (MI.isDebugValue()) {
MI.getOperand(FIOperandNum).ChangeToRegister(FrameReg, false /*isDef*/);
MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset);
return;
}
// fold constant into offset.
Offset += MI.getOperand(FIOperandNum + 1).getImm();
MI.getOperand(FIOperandNum + 1).ChangeToImmediate(0);
assert(Offset%4 == 0 && "Misaligned stack offset");
DEBUG(errs() << "Offset : " << Offset << "\n" << "<--------->\n");
Offset/=4;
unsigned Reg = MI.getOperand(0).getReg();
assert(XCore::GRRegsRegClass.contains(Reg) && "Unexpected register operand");
if (TFI->hasFP(MF)) {
if (isImmUs(Offset))
InsertFPImmInst(II, TII, Reg, FrameReg, Offset);
else
InsertFPConstInst(II, TII, Reg, FrameReg, Offset, RS);
} else {
if (isImmU16(Offset))
InsertSPImmInst(II, TII, Reg, Offset);
else
InsertSPConstInst(II, TII, Reg, Offset, RS);
}
// Erase old instruction.
MachineBasicBlock &MBB = *MI.getParent();
MBB.erase(II);
}
unsigned XCoreRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
const TargetFrameLowering *TFI = MF.getSubtarget().getFrameLowering();
return TFI->hasFP(MF) ? XCore::R10 : XCore::SP;
}