llvm-6502/lib/Target/Sparc/SparcRegisterInfo.cpp
2006-05-18 00:12:58 +00:00

226 lines
8.4 KiB
C++

//===- SparcRegisterInfo.cpp - SPARC 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 SPARC implementation of the MRegisterInfo class.
//
//===----------------------------------------------------------------------===//
#include "Sparc.h"
#include "SparcRegisterInfo.h"
#include "SparcSubtarget.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineLocation.h"
#include "llvm/Type.h"
#include "llvm/ADT/STLExtras.h"
#include <iostream>
using namespace llvm;
SparcRegisterInfo::SparcRegisterInfo(SparcSubtarget &st)
: SparcGenRegisterInfo(SP::ADJCALLSTACKDOWN, SP::ADJCALLSTACKUP),
Subtarget(st) {
}
void SparcRegisterInfo::
storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned SrcReg, int FI,
const TargetRegisterClass *RC) const {
// On the order of operands here: think "[FrameIdx + 0] = SrcReg".
if (RC == SP::IntRegsRegisterClass)
BuildMI(MBB, I, SP::STri, 3).addFrameIndex(FI).addImm(0).addReg(SrcReg);
else if (RC == SP::FPRegsRegisterClass)
BuildMI(MBB, I, SP::STFri, 3).addFrameIndex(FI).addImm(0).addReg(SrcReg);
else if (RC == SP::DFPRegsRegisterClass)
BuildMI(MBB, I, SP::STDFri, 3).addFrameIndex(FI).addImm(0).addReg(SrcReg);
else
assert(0 && "Can't store this register to stack slot");
}
void SparcRegisterInfo::
loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned DestReg, int FI,
const TargetRegisterClass *RC) const {
if (RC == SP::IntRegsRegisterClass)
BuildMI(MBB, I, SP::LDri, 2, DestReg).addFrameIndex(FI).addImm(0);
else if (RC == SP::FPRegsRegisterClass)
BuildMI(MBB, I, SP::LDFri, 2, DestReg).addFrameIndex(FI).addImm (0);
else if (RC == SP::DFPRegsRegisterClass)
BuildMI(MBB, I, SP::LDDFri, 2, DestReg).addFrameIndex(FI).addImm(0);
else
assert(0 && "Can't load this register from stack slot");
}
void SparcRegisterInfo::copyRegToReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned DestReg, unsigned SrcReg,
const TargetRegisterClass *RC) const {
if (RC == SP::IntRegsRegisterClass)
BuildMI(MBB, I, SP::ORrr, 2, DestReg).addReg(SP::G0).addReg(SrcReg);
else if (RC == SP::FPRegsRegisterClass)
BuildMI(MBB, I, SP::FMOVS, 1, DestReg).addReg(SrcReg);
else if (RC == SP::DFPRegsRegisterClass)
BuildMI(MBB, I, Subtarget.isV9() ? SP::FMOVD : SP::FpMOVD,
1, DestReg).addReg(SrcReg);
else
assert (0 && "Can't copy this register");
}
MachineInstr *SparcRegisterInfo::foldMemoryOperand(MachineInstr* MI,
unsigned OpNum,
int FI) const {
bool isFloat = false;
switch (MI->getOpcode()) {
case SP::ORrr:
if (MI->getOperand(1).isRegister() && MI->getOperand(1).getReg() == SP::G0&&
MI->getOperand(0).isRegister() && MI->getOperand(2).isRegister()) {
if (OpNum == 0) // COPY -> STORE
return BuildMI(SP::STri, 3).addFrameIndex(FI).addImm(0)
.addReg(MI->getOperand(2).getReg());
else // COPY -> LOAD
return BuildMI(SP::LDri, 2, MI->getOperand(0).getReg())
.addFrameIndex(FI).addImm(0);
}
break;
case SP::FMOVS:
isFloat = true;
// FALLTHROUGH
case SP::FMOVD:
if (OpNum == 0) // COPY -> STORE
return BuildMI(isFloat ? SP::STFri : SP::STDFri, 3)
.addFrameIndex(FI).addImm(0).addReg(MI->getOperand(1).getReg());
else // COPY -> LOAD
return BuildMI(isFloat ? SP::LDFri : SP::LDDFri, 2,
MI->getOperand(0).getReg()).addFrameIndex(FI).addImm(0);
break;
}
return 0;
}
const unsigned* SparcRegisterInfo::getCalleeSaveRegs() const {
static const unsigned CalleeSaveRegs[] = { 0 };
return CalleeSaveRegs;
}
const TargetRegisterClass* const*
SparcRegisterInfo::getCalleeSaveRegClasses() const {
static const TargetRegisterClass * const CalleeSaveRegClasses[] = { 0 };
return CalleeSaveRegClasses;
}
void SparcRegisterInfo::
eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
MachineInstr &MI = *I;
int Size = MI.getOperand(0).getImmedValue();
if (MI.getOpcode() == SP::ADJCALLSTACKDOWN)
Size = -Size;
if (Size)
BuildMI(MBB, I, SP::ADDri, 2, SP::O6).addReg(SP::O6).addImm(Size);
MBB.erase(I);
}
void
SparcRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const {
unsigned i = 0;
MachineInstr &MI = *II;
while (!MI.getOperand(i).isFrameIndex()) {
++i;
assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
}
int FrameIndex = MI.getOperand(i).getFrameIndex();
// Addressable stack objects are accessed using neg. offsets from %fp
MachineFunction &MF = *MI.getParent()->getParent();
int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex) +
MI.getOperand(i+1).getImmedValue();
// Replace frame index with a frame pointer reference.
if (Offset >= -4096 && Offset <= 4095) {
// If the offset is small enough to fit in the immediate field, directly
// encode it.
MI.getOperand(i).ChangeToRegister(SP::I6);
MI.getOperand(i+1).ChangeToImmediate(Offset);
} else {
// Otherwise, emit a G1 = SETHI %hi(offset). FIXME: it would be better to
// scavenge a register here instead of reserving G1 all of the time.
unsigned OffHi = (unsigned)Offset >> 10U;
BuildMI(*MI.getParent(), II, SP::SETHIi, 1, SP::G1).addImm(OffHi);
// Emit G1 = G1 + I6
BuildMI(*MI.getParent(), II, SP::ADDrr, 2,
SP::G1).addReg(SP::G1).addReg(SP::I6);
// Insert: G1+%lo(offset) into the user.
MI.getOperand(i).ChangeToRegister(SP::G1);
MI.getOperand(i+1).ChangeToImmediate(Offset & ((1 << 10)-1));
}
}
void SparcRegisterInfo::
processFunctionBeforeFrameFinalized(MachineFunction &MF) const {}
void SparcRegisterInfo::emitPrologue(MachineFunction &MF) const {
MachineBasicBlock &MBB = MF.front();
MachineFrameInfo *MFI = MF.getFrameInfo();
// Get the number of bytes to allocate from the FrameInfo
int NumBytes = (int) MFI->getStackSize();
// Emit the correct save instruction based on the number of bytes in
// the frame. Minimum stack frame size according to V8 ABI is:
// 16 words for register window spill
// 1 word for address of returned aggregate-value
// + 6 words for passing parameters on the stack
// ----------
// 23 words * 4 bytes per word = 92 bytes
NumBytes += 92;
// Round up to next doubleword boundary -- a double-word boundary
// is required by the ABI.
NumBytes = (NumBytes + 7) & ~7;
NumBytes = -NumBytes;
if (NumBytes >= -4096) {
BuildMI(MBB, MBB.begin(), SP::SAVEri, 2,
SP::O6).addImm(NumBytes).addReg(SP::O6);
} else {
MachineBasicBlock::iterator InsertPt = MBB.begin();
// Emit this the hard way. This clobbers G1 which we always know is
// available here.
unsigned OffHi = (unsigned)NumBytes >> 10U;
BuildMI(MBB, InsertPt, SP::SETHIi, 1, SP::G1).addImm(OffHi);
// Emit G1 = G1 + I6
BuildMI(MBB, InsertPt, SP::ORri, 2, SP::G1)
.addReg(SP::G1).addImm(NumBytes & ((1 << 10)-1));
BuildMI(MBB, InsertPt, SP::SAVErr, 2,
SP::O6).addReg(SP::O6).addReg(SP::G1);
}
}
void SparcRegisterInfo::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
MachineBasicBlock::iterator MBBI = prior(MBB.end());
assert(MBBI->getOpcode() == SP::RETL &&
"Can only put epilog before 'retl' instruction!");
BuildMI(MBB, MBBI, SP::RESTORErr, 2, SP::G0).addReg(SP::G0).addReg(SP::G0);
}
unsigned SparcRegisterInfo::getRARegister() const {
assert(0 && "What is the return address register");
return 0;
}
unsigned SparcRegisterInfo::getFrameRegister(MachineFunction &MF) const {
assert(0 && "What is the frame register");
return SP::G1;
}
#include "SparcGenRegisterInfo.inc"