llvm-6502/lib/Target/PowerPC/PPCRegisterInfo.cpp

328 lines
12 KiB
C++
Raw Normal View History

//===- PPC32RegisterInfo.cpp - PowerPC32 Register Information ---*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the PowerPC32 implementation of the MRegisterInfo class.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "reginfo"
#include "PowerPC.h"
#include "PowerPCInstrBuilder.h"
#include "PPC32RegisterInfo.h"
#include "llvm/Constants.h"
#include "llvm/Type.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/ADT/STLExtras.h"
#include <cstdlib>
#include <iostream>
using namespace llvm;
namespace llvm {
// Switch toggling compilation for AIX
extern cl::opt<bool> AIX;
}
PPC32RegisterInfo::PPC32RegisterInfo()
: PPC32GenRegisterInfo(PPC::ADJCALLSTACKDOWN, PPC::ADJCALLSTACKUP) {
ImmToIdxMap[PPC::LD] = PPC::LDX; ImmToIdxMap[PPC::STD] = PPC::STDX;
ImmToIdxMap[PPC::LBZ] = PPC::LBZX; ImmToIdxMap[PPC::STB] = PPC::STBX;
ImmToIdxMap[PPC::LHZ] = PPC::LHZX; ImmToIdxMap[PPC::LHA] = PPC::LHAX;
ImmToIdxMap[PPC::LWZ] = PPC::LWZX; ImmToIdxMap[PPC::LWA] = PPC::LWAX;
ImmToIdxMap[PPC::LFS] = PPC::LFSX; ImmToIdxMap[PPC::LFD] = PPC::LFDX;
ImmToIdxMap[PPC::STH] = PPC::STHX; ImmToIdxMap[PPC::STW] = PPC::STWX;
ImmToIdxMap[PPC::STFS] = PPC::STFSX; ImmToIdxMap[PPC::STFD] = PPC::STFDX;
ImmToIdxMap[PPC::ADDI] = PPC::ADD;
}
static const TargetRegisterClass *getClass(unsigned SrcReg) {
if (PPC32::FPRCRegisterClass->contains(SrcReg))
return PPC32::FPRCRegisterClass;
assert(PPC32::GPRCRegisterClass->contains(SrcReg) && "Reg not FPR or GPR");
return PPC32::GPRCRegisterClass;
}
static unsigned getIdx(const TargetRegisterClass *RC) {
if (RC == PPC32::GPRCRegisterClass) {
switch (RC->getSize()) {
default: assert(0 && "Invalid data size!");
case 1: return 0;
case 2: return 1;
case 4: return 2;
}
} else if (RC == PPC32::FPRCRegisterClass) {
switch (RC->getSize()) {
default: assert(0 && "Invalid data size!");
case 4: return 3;
case 8: return 4;
}
} else if (RC == PPC32::CRRCRegisterClass) {
switch (RC->getSize()) {
default: assert(0 && "Invalid data size!");
case 4: return 2;
}
}
std::cerr << "Invalid register class to getIdx()!\n";
abort();
}
void
PPC32RegisterInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned SrcReg, int FrameIdx) const {
static const unsigned Opcode[] = {
PPC::STB, PPC::STH, PPC::STW, PPC::STFS, PPC::STFD
};
unsigned OC = Opcode[getIdx(getClass(SrcReg))];
if (SrcReg == PPC::LR) {
BuildMI(MBB, MI, PPC::MFLR, 1, PPC::R11).addReg(PPC::LR);
addFrameReference(BuildMI(MBB, MI, OC, 3).addReg(PPC::R11),FrameIdx);
} else if (PPC32::CRRCRegisterClass == getClass(SrcReg)) {
BuildMI(MBB, MI, PPC::MFCR, 0, PPC::R11);
addFrameReference(BuildMI(MBB, MI, OC, 3).addReg(PPC::R11),FrameIdx);
} else {
addFrameReference(BuildMI(MBB, MI, OC, 3).addReg(SrcReg),FrameIdx);
}
}
void
PPC32RegisterInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, int FrameIdx) const{
static const unsigned Opcode[] = {
PPC::LBZ, PPC::LHZ, PPC::LWZ, PPC::LFS, PPC::LFD
};
unsigned OC = Opcode[getIdx(getClass(DestReg))];
if (DestReg == PPC::LR) {
addFrameReference(BuildMI(MBB, MI, OC, 2, PPC::R11), FrameIdx);
BuildMI(MBB, MI, PPC::MTLR, 1).addReg(PPC::R11);
} else if (PPC32::CRRCRegisterClass == getClass(DestReg)) {
addFrameReference(BuildMI(MBB, MI, OC, 2, PPC::R11), FrameIdx);
BuildMI(MBB, MI, PPC::MTCRF, 1, DestReg).addReg(PPC::R11);
} else {
addFrameReference(BuildMI(MBB, MI, OC, 2, DestReg), FrameIdx);
}
}
void PPC32RegisterInfo::copyRegToReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, unsigned SrcReg,
const TargetRegisterClass *RC) const {
MachineInstr *I;
if (RC == PPC32::GPRCRegisterClass) {
BuildMI(MBB, MI, PPC::OR, 2, DestReg).addReg(SrcReg).addReg(SrcReg);
} else if (RC == PPC32::FPRCRegisterClass) {
BuildMI(MBB, MI, PPC::FMR, 1, DestReg).addReg(SrcReg);
} else if (RC == PPC32::CRRCRegisterClass) {
BuildMI(MBB, MI, PPC::MCRF, 1, DestReg).addReg(SrcReg);
} else {
std::cerr << "Attempt to copy register that is not GPR or FPR";
abort();
}
}
//===----------------------------------------------------------------------===//
// Stack Frame Processing methods
//===----------------------------------------------------------------------===//
// hasFP - Return true if the specified function should have a dedicated frame
// pointer register. This is true if the function has variable sized allocas or
// if frame pointer elimination is disabled.
//
static bool hasFP(MachineFunction &MF) {
MachineFrameInfo *MFI = MF.getFrameInfo();
return MFI->hasVarSizedObjects();
}
void PPC32RegisterInfo::
eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
if (hasFP(MF)) {
// If we have a frame pointer, convert as follows:
// ADJCALLSTACKDOWN -> addi, r1, r1, -amount
// ADJCALLSTACKUP -> addi, r1, r1, amount
MachineInstr *Old = I;
unsigned Amount = Old->getOperand(0).getImmedValue();
if (Amount != 0) {
// We need to keep the stack aligned properly. To do this, we round the
// amount of space needed for the outgoing arguments up to the next
// alignment boundary.
unsigned Align = MF.getTarget().getFrameInfo()->getStackAlignment();
Amount = (Amount+Align-1)/Align*Align;
// Replace the pseudo instruction with a new instruction...
if (Old->getOpcode() == PPC::ADJCALLSTACKDOWN) {
MBB.insert(I, BuildMI(PPC::ADDI, 2, PPC::R1).addReg(PPC::R1)
.addSImm(-Amount));
} else {
assert(Old->getOpcode() == PPC::ADJCALLSTACKUP);
MBB.insert(I, BuildMI(PPC::ADDI, 2, PPC::R1).addReg(PPC::R1)
.addSImm(Amount));
}
}
}
MBB.erase(I);
}
void
PPC32RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const {
unsigned i = 0;
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
MachineFunction &MF = *MBB.getParent();
while (!MI.getOperand(i).isFrameIndex()) {
++i;
assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
}
int FrameIndex = MI.getOperand(i).getFrameIndex();
// Replace the FrameIndex with base register with GPR1 (SP) or GPR31 (FP).
MI.SetMachineOperandReg(i, hasFP(MF) ? PPC::R31 : PPC::R1);
// Take into account whether it's an add or mem instruction
unsigned OffIdx = (i == 2) ? 1 : 2;
// Now add the frame object offset to the offset from r1.
int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex) +
MI.getOperand(OffIdx).getImmedValue();
// If we're not using a Frame Pointer that has been set to the value of the
// SP before having the stack size subtracted from it, then add the stack size
// to Offset to get the correct offset.
Offset += MF.getFrameInfo()->getStackSize();
if (Offset > 32767 || Offset < -32768) {
// Insert a set of r0 with the full offset value before the ld, st, or add
MachineBasicBlock *MBB = MI.getParent();
MBB->insert(II, BuildMI(PPC::LIS, 1, PPC::R0).addSImm(Offset >> 16));
MBB->insert(II, BuildMI(PPC::ORI, 2, PPC::R0).addReg(PPC::R0)
.addImm(Offset));
// convert into indexed form of the instruction
// sth 0:rA, 1:imm 2:(rB) ==> sthx 0:rA, 2:rB, 1:r0
// addi 0:rA 1:rB, 2, imm ==> add 0:rA, 1:rB, 2:r0
unsigned NewOpcode = const_cast<std::map<unsigned, unsigned>& >(ImmToIdxMap)[MI.getOpcode()];
assert(NewOpcode && "No indexed form of load or store available!");
MI.setOpcode(NewOpcode);
MI.SetMachineOperandReg(1, MI.getOperand(i).getReg());
MI.SetMachineOperandReg(2, PPC::R0);
} else {
MI.SetMachineOperandConst(OffIdx,MachineOperand::MO_SignExtendedImmed,Offset);
}
}
void PPC32RegisterInfo::emitPrologue(MachineFunction &MF) const {
MachineBasicBlock &MBB = MF.front(); // Prolog goes in entry BB
MachineBasicBlock::iterator MBBI = MBB.begin();
MachineFrameInfo *MFI = MF.getFrameInfo();
MachineInstr *MI;
// Get the number of bytes to allocate from the FrameInfo
unsigned NumBytes = MFI->getStackSize();
// If we have calls, we cannot use the red zone to store callee save registers
// and we must set up a stack frame, so calculate the necessary size here.
if (MFI->hasCalls()) {
// We reserve argument space for call sites in the function immediately on
// entry to the current function. This eliminates the need for add/sub
// brackets around call sites.
NumBytes += MFI->getMaxCallFrameSize();
}
// Do we need to allocate space on the stack?
if (NumBytes == 0) return;
// Add the size of R1 to NumBytes size for the store of R1 to the bottom
// of the stack and round the size to a multiple of the alignment.
unsigned Align = MF.getTarget().getFrameInfo()->getStackAlignment();
unsigned GPRSize = getSpillSize(PPC::R1)/8;
unsigned Size = hasFP(MF) ? GPRSize + GPRSize : GPRSize;
NumBytes = (NumBytes+Size+Align-1)/Align*Align;
// Update frame info to pretend that this is part of the stack...
MFI->setStackSize(NumBytes);
// adjust stack pointer: r1 -= numbytes
if (NumBytes <= 32768) {
MI=BuildMI(PPC::STWU,3).addReg(PPC::R1).addSImm(-NumBytes).addReg(PPC::R1);
MBB.insert(MBBI, MI);
} else {
int NegNumbytes = -NumBytes;
MI = BuildMI(PPC::LIS, 1, PPC::R0).addSImm(NegNumbytes >> 16);
MBB.insert(MBBI, MI);
MI = BuildMI(PPC::ORI, 2, PPC::R0).addReg(PPC::R0)
.addImm(NegNumbytes & 0xFFFF);
MBB.insert(MBBI, MI);
MI = BuildMI(PPC::STWUX, 3).addReg(PPC::R1).addReg(PPC::R1).addReg(PPC::R0);
MBB.insert(MBBI, MI);
}
if (hasFP(MF)) {
MI = BuildMI(PPC::STW, 3).addReg(PPC::R31).addSImm(GPRSize).addReg(PPC::R1);
MBB.insert(MBBI, MI);
MI = BuildMI(PPC::OR, 2, PPC::R31).addReg(PPC::R1).addReg(PPC::R1);
MBB.insert(MBBI, MI);
}
}
void PPC32RegisterInfo::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
MachineBasicBlock::iterator MBBI = prior(MBB.end());
MachineInstr *MI;
assert(MBBI->getOpcode() == PPC::BLR &&
"Can only insert epilog into returning blocks");
// Get the number of bytes allocated from the FrameInfo...
unsigned NumBytes = MFI->getStackSize();
unsigned GPRSize = getSpillSize(PPC::R31)/8;
if (NumBytes != 0) {
if (hasFP(MF)) {
MI = BuildMI(PPC::LWZ, 2, PPC::R31).addSImm(GPRSize).addReg(PPC::R31);
MBB.insert(MBBI, MI);
}
MI = BuildMI(PPC::LWZ, 2, PPC::R1).addSImm(0).addReg(PPC::R1);
MBB.insert(MBBI, MI);
}
}
#include "PPC32GenRegisterInfo.inc"
const TargetRegisterClass*
PPC32RegisterInfo::getRegClassForType(const Type* Ty) const {
switch (Ty->getTypeID()) {
default: assert(0 && "Invalid type to getClass!");
case Type::LongTyID:
case Type::ULongTyID: assert(0 && "Long values can't fit in registers!");
case Type::BoolTyID:
case Type::SByteTyID:
case Type::UByteTyID:
case Type::ShortTyID:
case Type::UShortTyID:
case Type::IntTyID:
case Type::UIntTyID:
case Type::PointerTyID: return &GPRCInstance;
case Type::FloatTyID:
case Type::DoubleTyID: return &FPRCInstance;
}
}