1 //===-- Mips16FrameLowering.cpp - Mips16 Frame Information ----------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains the Mips16 implementation of TargetFrameLowering class.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "Mips16FrameLowering.h"
15 #include "MipsInstrInfo.h"
16 #include "MCTargetDesc/MipsBaseInfo.h"
17 #include "llvm/Function.h"
18 #include "llvm/CodeGen/MachineFrameInfo.h"
19 #include "llvm/CodeGen/MachineFunction.h"
20 #include "llvm/CodeGen/MachineInstrBuilder.h"
21 #include "llvm/CodeGen/MachineModuleInfo.h"
22 #include "llvm/CodeGen/MachineRegisterInfo.h"
23 #include "llvm/Target/TargetData.h"
24 #include "llvm/Target/TargetOptions.h"
25 #include "llvm/Support/CommandLine.h"
26
27 using namespace llvm;
28
emitPrologue(MachineFunction & MF) const29 void Mips16FrameLowering::emitPrologue(MachineFunction &MF) const {
30 MachineBasicBlock &MBB = MF.front();
31 MachineFrameInfo *MFI = MF.getFrameInfo();
32 const MipsInstrInfo &TII =
33 *static_cast<const MipsInstrInfo*>(MF.getTarget().getInstrInfo());
34 MachineBasicBlock::iterator MBBI = MBB.begin();
35 DebugLoc dl = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
36 uint64_t StackSize = MFI->getStackSize();
37
38 // No need to allocate space on the stack.
39 if (StackSize == 0 && !MFI->adjustsStack()) return;
40
41 // Adjust stack.
42 if (isInt<16>(-StackSize))
43 BuildMI(MBB, MBBI, dl, TII.get(Mips::SaveRaF16)).addImm(StackSize);
44 }
45
emitEpilogue(MachineFunction & MF,MachineBasicBlock & MBB) const46 void Mips16FrameLowering::emitEpilogue(MachineFunction &MF,
47 MachineBasicBlock &MBB) const {
48 MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
49 MachineFrameInfo *MFI = MF.getFrameInfo();
50 const MipsInstrInfo &TII =
51 *static_cast<const MipsInstrInfo*>(MF.getTarget().getInstrInfo());
52 DebugLoc dl = MBBI->getDebugLoc();
53 uint64_t StackSize = MFI->getStackSize();
54
55 if (!StackSize)
56 return;
57
58 // Adjust stack.
59 if (isInt<16>(StackSize))
60 // assumes stacksize multiple of 8
61 BuildMI(MBB, MBBI, dl, TII.get(Mips::RestoreRaF16)).addImm(StackSize);
62 }
63
64 bool Mips16FrameLowering::
spillCalleeSavedRegisters(MachineBasicBlock & MBB,MachineBasicBlock::iterator MI,const std::vector<CalleeSavedInfo> & CSI,const TargetRegisterInfo * TRI) const65 spillCalleeSavedRegisters(MachineBasicBlock &MBB,
66 MachineBasicBlock::iterator MI,
67 const std::vector<CalleeSavedInfo> &CSI,
68 const TargetRegisterInfo *TRI) const {
69 // FIXME: implement.
70 return true;
71 }
72
73 bool
hasReservedCallFrame(const MachineFunction & MF) const74 Mips16FrameLowering::hasReservedCallFrame(const MachineFunction &MF) const {
75 // FIXME: implement.
76 return true;
77 }
78
79 void Mips16FrameLowering::
processFunctionBeforeCalleeSavedScan(MachineFunction & MF,RegScavenger * RS) const80 processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
81 RegScavenger *RS) const {
82 }
83
84 const MipsFrameLowering *
createMips16FrameLowering(const MipsSubtarget & ST)85 llvm::createMips16FrameLowering(const MipsSubtarget &ST) {
86 return new Mips16FrameLowering(ST);
87 }
88