llvm-project/llvm/lib/Target/XCore/XCoreMachineFunctionInfo.cpp

81 lines
2.9 KiB
C++

//===-- XCoreMachineFunctionInfo.cpp - XCore machine function info --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "XCoreMachineFunctionInfo.h"
#include "XCoreInstrInfo.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/IR/Function.h"
using namespace llvm;
void XCoreFunctionInfo::anchor() { }
bool XCoreFunctionInfo::isLargeFrame(const MachineFunction &MF) const {
if (CachedEStackSize == -1) {
CachedEStackSize = MF.getFrameInfo().estimateStackSize(MF);
}
// isLargeFrame() is used when deciding if spill slots should be added to
// allow eliminateFrameIndex() to scavenge registers.
// This is only required when there is no FP and offsets are greater than
// ~256KB (~64Kwords). Thus only for code run on the emulator!
//
// The arbitrary value of 0xf000 allows frames of up to ~240KB before spill
// slots are added for the use of eliminateFrameIndex() register scavenging.
// For frames less than 240KB, it is assumed that there will be less than
// 16KB of function arguments.
return CachedEStackSize > 0xf000;
}
int XCoreFunctionInfo::createLRSpillSlot(MachineFunction &MF) {
if (LRSpillSlotSet) {
return LRSpillSlot;
}
const TargetRegisterClass &RC = XCore::GRRegsRegClass;
const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
MachineFrameInfo &MFI = MF.getFrameInfo();
if (! MF.getFunction().isVarArg()) {
// A fixed offset of 0 allows us to save / restore LR using entsp / retsp.
LRSpillSlot = MFI.CreateFixedObject(TRI.getSpillSize(RC), 0, true);
} else {
LRSpillSlot = MFI.CreateStackObject(TRI.getSpillSize(RC),
TRI.getSpillAlignment(RC), true);
}
LRSpillSlotSet = true;
return LRSpillSlot;
}
int XCoreFunctionInfo::createFPSpillSlot(MachineFunction &MF) {
if (FPSpillSlotSet) {
return FPSpillSlot;
}
const TargetRegisterClass &RC = XCore::GRRegsRegClass;
const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
MachineFrameInfo &MFI = MF.getFrameInfo();
FPSpillSlot = MFI.CreateStackObject(TRI.getSpillSize(RC),
TRI.getSpillAlignment(RC), true);
FPSpillSlotSet = true;
return FPSpillSlot;
}
const int* XCoreFunctionInfo::createEHSpillSlot(MachineFunction &MF) {
if (EHSpillSlotSet) {
return EHSpillSlot;
}
const TargetRegisterClass &RC = XCore::GRRegsRegClass;
const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
MachineFrameInfo &MFI = MF.getFrameInfo();
unsigned Size = TRI.getSpillSize(RC);
unsigned Align = TRI.getSpillAlignment(RC);
EHSpillSlot[0] = MFI.CreateStackObject(Size, Align, true);
EHSpillSlot[1] = MFI.CreateStackObject(Size, Align, true);
EHSpillSlotSet = true;
return EHSpillSlot;
}