1//===-- XCoreMachineFunctionInfo.cpp - XCore machine function info --------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "XCoreMachineFunctionInfo.h"
10#include "XCoreInstrInfo.h"
11#include "llvm/CodeGen/TargetSubtargetInfo.h"
12#include "llvm/IR/Function.h"
13
14using namespace llvm;
15
16void XCoreFunctionInfo::anchor() { }
17
18bool XCoreFunctionInfo::isLargeFrame(const MachineFunction &MF) const {
19  if (CachedEStackSize == -1) {
20    CachedEStackSize = MF.getFrameInfo().estimateStackSize(MF);
21  }
22  // isLargeFrame() is used when deciding if spill slots should be added to
23  // allow eliminateFrameIndex() to scavenge registers.
24  // This is only required when there is no FP and offsets are greater than
25  // ~256KB (~64Kwords). Thus only for code run on the emulator!
26  //
27  // The arbitrary value of 0xf000 allows frames of up to ~240KB before spill
28  // slots are added for the use of eliminateFrameIndex() register scavenging.
29  // For frames less than 240KB, it is assumed that there will be less than
30  // 16KB of function arguments.
31  return CachedEStackSize > 0xf000;
32}
33
34int XCoreFunctionInfo::createLRSpillSlot(MachineFunction &MF) {
35  if (LRSpillSlotSet) {
36    return LRSpillSlot;
37  }
38  const TargetRegisterClass &RC = XCore::GRRegsRegClass;
39  const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
40  MachineFrameInfo &MFI = MF.getFrameInfo();
41  if (! MF.getFunction().isVarArg()) {
42    // A fixed offset of 0 allows us to save / restore LR using entsp / retsp.
43    LRSpillSlot = MFI.CreateFixedObject(TRI.getSpillSize(RC), 0, true);
44  } else {
45    LRSpillSlot = MFI.CreateStackObject(TRI.getSpillSize(RC),
46                                        TRI.getSpillAlign(RC), true);
47  }
48  LRSpillSlotSet = true;
49  return LRSpillSlot;
50}
51
52int XCoreFunctionInfo::createFPSpillSlot(MachineFunction &MF) {
53  if (FPSpillSlotSet) {
54    return FPSpillSlot;
55  }
56  const TargetRegisterClass &RC = XCore::GRRegsRegClass;
57  const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
58  MachineFrameInfo &MFI = MF.getFrameInfo();
59  FPSpillSlot =
60      MFI.CreateStackObject(TRI.getSpillSize(RC), TRI.getSpillAlign(RC), true);
61  FPSpillSlotSet = true;
62  return FPSpillSlot;
63}
64
65const int* XCoreFunctionInfo::createEHSpillSlot(MachineFunction &MF) {
66  if (EHSpillSlotSet) {
67    return EHSpillSlot;
68  }
69  const TargetRegisterClass &RC = XCore::GRRegsRegClass;
70  const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
71  MachineFrameInfo &MFI = MF.getFrameInfo();
72  unsigned Size = TRI.getSpillSize(RC);
73  Align Alignment = TRI.getSpillAlign(RC);
74  EHSpillSlot[0] = MFI.CreateStackObject(Size, Alignment, true);
75  EHSpillSlot[1] = MFI.CreateStackObject(Size, Alignment, true);
76  EHSpillSlotSet = true;
77  return EHSpillSlot;
78}
79
80