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 
14 using namespace llvm;
15 
16 void XCoreFunctionInfo::anchor() { }
17 
18 MachineFunctionInfo *XCoreFunctionInfo::clone(
19     BumpPtrAllocator &Allocator, MachineFunction &DestMF,
20     const DenseMap<MachineBasicBlock *, MachineBasicBlock *> &Src2DstMBB)
21     const {
22   return DestMF.cloneInfo<XCoreFunctionInfo>(*this);
23 }
24 
25 bool XCoreFunctionInfo::isLargeFrame(const MachineFunction &MF) const {
26   if (CachedEStackSize == -1) {
27     CachedEStackSize = MF.getFrameInfo().estimateStackSize(MF);
28   }
29   // isLargeFrame() is used when deciding if spill slots should be added to
30   // allow eliminateFrameIndex() to scavenge registers.
31   // This is only required when there is no FP and offsets are greater than
32   // ~256KB (~64Kwords). Thus only for code run on the emulator!
33   //
34   // The arbitrary value of 0xf000 allows frames of up to ~240KB before spill
35   // slots are added for the use of eliminateFrameIndex() register scavenging.
36   // For frames less than 240KB, it is assumed that there will be less than
37   // 16KB of function arguments.
38   return CachedEStackSize > 0xf000;
39 }
40 
41 int XCoreFunctionInfo::createLRSpillSlot(MachineFunction &MF) {
42   if (LRSpillSlotSet) {
43     return LRSpillSlot;
44   }
45   const TargetRegisterClass &RC = XCore::GRRegsRegClass;
46   const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
47   MachineFrameInfo &MFI = MF.getFrameInfo();
48   if (! MF.getFunction().isVarArg()) {
49     // A fixed offset of 0 allows us to save / restore LR using entsp / retsp.
50     LRSpillSlot = MFI.CreateFixedObject(TRI.getSpillSize(RC), 0, true);
51   } else {
52     LRSpillSlot = MFI.CreateStackObject(TRI.getSpillSize(RC),
53                                         TRI.getSpillAlign(RC), true);
54   }
55   LRSpillSlotSet = true;
56   return LRSpillSlot;
57 }
58 
59 int XCoreFunctionInfo::createFPSpillSlot(MachineFunction &MF) {
60   if (FPSpillSlotSet) {
61     return FPSpillSlot;
62   }
63   const TargetRegisterClass &RC = XCore::GRRegsRegClass;
64   const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
65   MachineFrameInfo &MFI = MF.getFrameInfo();
66   FPSpillSlot =
67       MFI.CreateStackObject(TRI.getSpillSize(RC), TRI.getSpillAlign(RC), true);
68   FPSpillSlotSet = true;
69   return FPSpillSlot;
70 }
71 
72 const int* XCoreFunctionInfo::createEHSpillSlot(MachineFunction &MF) {
73   if (EHSpillSlotSet) {
74     return EHSpillSlot;
75   }
76   const TargetRegisterClass &RC = XCore::GRRegsRegClass;
77   const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
78   MachineFrameInfo &MFI = MF.getFrameInfo();
79   unsigned Size = TRI.getSpillSize(RC);
80   Align Alignment = TRI.getSpillAlign(RC);
81   EHSpillSlot[0] = MFI.CreateStackObject(Size, Alignment, true);
82   EHSpillSlot[1] = MFI.CreateStackObject(Size, Alignment, true);
83   EHSpillSlotSet = true;
84   return EHSpillSlot;
85 }
86 
87