llvm-6502/lib/Target/Sparc/SparcRegisterInfo.cpp
Jakob Stoklund Olesen 2b9355f2d9 SPARC v9 stack pointer bias.
64-bit SPARC v9 processes use biased stack and frame pointers, so the
current function's stack frame is located at %sp+BIAS .. %fp+BIAS where
BIAS = 2047.

This makes more local variables directly accessible via [%fp+simm13]
addressing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178965 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-06 21:38:57 +00:00

112 lines
4.0 KiB
C++

//===-- SparcRegisterInfo.cpp - SPARC 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 SPARC implementation of the TargetRegisterInfo class.
//
//===----------------------------------------------------------------------===//
#include "SparcRegisterInfo.h"
#include "Sparc.h"
#include "SparcSubtarget.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/IR/Type.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Target/TargetInstrInfo.h"
#define GET_REGINFO_TARGET_DESC
#include "SparcGenRegisterInfo.inc"
using namespace llvm;
SparcRegisterInfo::SparcRegisterInfo(SparcSubtarget &st,
const TargetInstrInfo &tii)
: SparcGenRegisterInfo(SP::I7), Subtarget(st), TII(tii) {
}
const uint16_t* SparcRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF)
const {
static const uint16_t CalleeSavedRegs[] = { 0 };
return CalleeSavedRegs;
}
BitVector SparcRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
BitVector Reserved(getNumRegs());
// FIXME: G1 reserved for now for large imm generation by frame code.
Reserved.set(SP::G1);
Reserved.set(SP::G2);
Reserved.set(SP::G3);
Reserved.set(SP::G4);
Reserved.set(SP::O6);
Reserved.set(SP::I6);
Reserved.set(SP::I7);
Reserved.set(SP::G0);
Reserved.set(SP::G5);
Reserved.set(SP::G6);
Reserved.set(SP::G7);
return Reserved;
}
const TargetRegisterClass*
SparcRegisterInfo::getPointerRegClass(const MachineFunction &MF,
unsigned Kind) const {
return Subtarget.is64Bit() ? &SP::I64RegsRegClass : &SP::IntRegsRegClass;
}
void
SparcRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
int SPAdj, unsigned FIOperandNum,
RegScavenger *RS) const {
assert(SPAdj == 0 && "Unexpected");
MachineInstr &MI = *II;
DebugLoc dl = MI.getDebugLoc();
int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
// Addressable stack objects are accessed using neg. offsets from %fp
MachineFunction &MF = *MI.getParent()->getParent();
int64_t Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex) +
MI.getOperand(FIOperandNum + 1).getImm() +
Subtarget.getStackPointerBias();
// 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(FIOperandNum).ChangeToRegister(SP::I6, false);
MI.getOperand(FIOperandNum + 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, dl, TII.get(SP::SETHIi), SP::G1).addImm(OffHi);
// Emit G1 = G1 + I6
BuildMI(*MI.getParent(), II, dl, TII.get(SP::ADDrr), SP::G1).addReg(SP::G1)
.addReg(SP::I6);
// Insert: G1+%lo(offset) into the user.
MI.getOperand(FIOperandNum).ChangeToRegister(SP::G1, false);
MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset & ((1 << 10)-1));
}
}
unsigned SparcRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
return SP::I6;
}
unsigned SparcRegisterInfo::getEHExceptionRegister() const {
llvm_unreachable("What is the exception register");
}
unsigned SparcRegisterInfo::getEHHandlerRegister() const {
llvm_unreachable("What is the exception handler register");
}