llvm-6502/lib/Target/Alpha/AlphaRegisterInfo.cpp
2005-02-05 02:24:26 +00:00

280 lines
10 KiB
C++

//===- AlphaRegisterInfo.cpp - Alpha 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 Alpha implementation of the MRegisterInfo class.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "reginfo"
#include "Alpha.h"
#include "AlphaRegisterInfo.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;
AlphaRegisterInfo::AlphaRegisterInfo()
: AlphaGenRegisterInfo(Alpha::ADJUSTSTACKDOWN, Alpha::ADJUSTSTACKUP)
{
}
static const TargetRegisterClass *getClass(unsigned SrcReg) {
if (Alpha::FPRCRegisterClass->contains(SrcReg))
return Alpha::FPRCRegisterClass;
assert(Alpha::GPRCRegisterClass->contains(SrcReg) && "Reg not FPR or GPR");
return Alpha::GPRCRegisterClass;
}
void
AlphaRegisterInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned SrcReg, int FrameIdx) const {
//std::cerr << "Trying to store " << getPrettyName(SrcReg) << " to " << FrameIdx << "\n";
//BuildMI(MBB, MI, Alpha::WTF, 0).addReg(SrcReg);
if (getClass(SrcReg) == Alpha::FPRCRegisterClass)
BuildMI(MBB, MI, Alpha::STT, 3).addReg(SrcReg).addFrameIndex(FrameIdx).addReg(Alpha::F31);
else if (getClass(SrcReg) == Alpha::GPRCRegisterClass)
BuildMI(MBB, MI, Alpha::STQ, 3).addReg(SrcReg).addFrameIndex(FrameIdx).addReg(Alpha::F31);
else
abort();
}
void
AlphaRegisterInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, int FrameIdx) const{
//std::cerr << "Trying to load " << getPrettyName(DestReg) << " to " << FrameIdx << "\n";
if (getClass(DestReg) == Alpha::FPRCRegisterClass)
BuildMI(MBB, MI, Alpha::LDT, 2, DestReg).addFrameIndex(FrameIdx).addReg(Alpha::F31);
else if (getClass(DestReg) == Alpha::GPRCRegisterClass)
BuildMI(MBB, MI, Alpha::LDQ, 2, DestReg).addFrameIndex(FrameIdx).addReg(Alpha::F31);
else
abort();
}
void AlphaRegisterInfo::copyRegToReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, unsigned SrcReg,
const TargetRegisterClass *RC) const {
// std::cerr << "copyRegToReg " << DestReg << " <- " << SrcReg << "\n";
if (RC == Alpha::GPRCRegisterClass) {
BuildMI(MBB, MI, Alpha::BIS, 2, DestReg).addReg(SrcReg).addReg(SrcReg);
} else if (RC == Alpha::FPRCRegisterClass) {
BuildMI(MBB, MI, Alpha::CPYS, 2, DestReg).addReg(SrcReg).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 AlphaRegisterInfo::
eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
if (hasFP(MF)) {
assert(0 && "TODO");
// If we have a frame pointer, turn the adjcallstackup instruction into a
// 'sub ESP, <amt>' and the adjcallstackdown instruction into 'add ESP,
// <amt>'
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;
// MachineInstr *New;
// if (Old->getOpcode() == X86::ADJCALLSTACKDOWN) {
// New=BuildMI(X86::SUB32ri, 1, X86::ESP, MachineOperand::UseAndDef)
// .addZImm(Amount);
// } else {
// assert(Old->getOpcode() == X86::ADJCALLSTACKUP);
// New=BuildMI(X86::ADD32ri, 1, X86::ESP, MachineOperand::UseAndDef)
// .addZImm(Amount);
// }
// Replace the pseudo instruction with a new instruction...
//MBB.insert(I, New);
abort();
}
}
MBB.erase(I);
}
void
AlphaRegisterInfo::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();
// Add the base register of R30 (SP) or R15 (FP).
MI.SetMachineOperandReg(i + 1, hasFP(MF) ? Alpha::R15 : Alpha::R30);
// Now add the frame object offset to the offset from r1.
int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex);
// 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) {
std::cerr << "Offset needs to be " << Offset << "\n";
assert(0 && "stack too big");
} else {
MI.SetMachineOperandConst(i, MachineOperand::MO_SignExtendedImmed, Offset);
}
}
void AlphaRegisterInfo::emitPrologue(MachineFunction &MF) const {
MachineBasicBlock &MBB = MF.front(); // Prolog goes in entry BB
MachineBasicBlock::iterator MBBI = MBB.begin();
MachineFrameInfo *MFI = MF.getFrameInfo();
MachineInstr *MI;
//handle GOP offset
MI = BuildMI(Alpha::LDGP, 0);
MBB.insert(MBBI, MI);
// Get the number of bytes to allocate from the FrameInfo
unsigned NumBytes = MFI->getStackSize();
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();
std::cerr << "Added " << MFI->getMaxCallFrameSize() << " to the stack due to calls\n";
}
// Do we need to allocate space on the stack?
if (NumBytes == 0) return;
// Add the size of R30 to NumBytes size for the store of R30 to the
// stack
// std::cerr << "Spillsize of R30 is " << getSpillSize(Alpha::R30) << "\n";
// NumBytes = NumBytes + getSpillSize(Alpha::R30)/8;
// Update frame info to pretend that this is part of the stack...
MFI->setStackSize(NumBytes);
// adjust stack pointer: r30 -= numbytes
if (NumBytes <= 32767) {
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(-NumBytes).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
} else if ((unsigned long)NumBytes <= (unsigned long)32767 * (unsigned long)65536) {
long y = NumBytes / 65536;
if (NumBytes % 65536 > 32767)
++y;
MI=BuildMI(Alpha::LDAH, 2, Alpha::R30).addImm(-y).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(-(NumBytes - y * 65536)).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
} else {
std::cerr << "Too big a stack frame at " << NumBytes << "\n";
abort();
}
}
void AlphaRegisterInfo::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
MachineBasicBlock::iterator MBBI = prior(MBB.end());
MachineInstr *MI;
assert((MBBI->getOpcode() == Alpha::RET || MBBI->getOpcode() == Alpha::RETURN) &&
"Can only insert epilog into returning blocks");
// Get the number of bytes allocated from the FrameInfo...
unsigned NumBytes = MFI->getStackSize();
if (NumBytes != 0)
{
if (NumBytes <= 32767) {
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(NumBytes).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
} else if ((unsigned long)NumBytes <= (unsigned long)32767 * (unsigned long)65536) {
long y = NumBytes / 65536;
if (NumBytes % 65536 > 32767)
++y;
MI=BuildMI(Alpha::LDAH, 2, Alpha::R30).addImm(y).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
MI=BuildMI(Alpha::LDA, 2, Alpha::R30).addImm(NumBytes - y * 65536).addReg(Alpha::R30);
MBB.insert(MBBI, MI);
} else {
std::cerr << "Too big a stack frame at " << NumBytes << "\n";
abort();
}
}
}
#include "AlphaGenRegisterInfo.inc"
const TargetRegisterClass*
AlphaRegisterInfo::getRegClassForType(const Type* Ty) const {
switch (Ty->getTypeID()) {
default: assert(0 && "Invalid type to getClass!");
case Type::BoolTyID:
case Type::SByteTyID:
case Type::UByteTyID:
case Type::ShortTyID:
case Type::UShortTyID:
case Type::IntTyID:
case Type::UIntTyID:
case Type::PointerTyID:
case Type::LongTyID:
case Type::ULongTyID: return &GPRCInstance;
case Type::FloatTyID:
case Type::DoubleTyID: return &FPRCInstance;
}
}
std::string AlphaRegisterInfo::getPrettyName(unsigned reg)
{
std::string s(RegisterDescriptors[reg].Name);
return s;
}