1 //=======- NVPTXFrameLowering.cpp - NVPTX Frame Information ---*- C++ -*-=====//
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 NVPTX implementation of TargetFrameLowering class.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "NVPTXFrameLowering.h"
15 #include "NVPTX.h"
16 #include "NVPTXRegisterInfo.h"
17 #include "NVPTXSubtarget.h"
18 #include "NVPTXTargetMachine.h"
19 #include "llvm/ADT/BitVector.h"
20 #include "llvm/CodeGen/MachineFrameInfo.h"
21 #include "llvm/CodeGen/MachineFunction.h"
22 #include "llvm/CodeGen/MachineInstrBuilder.h"
23 #include "llvm/CodeGen/MachineRegisterInfo.h"
24 #include "llvm/MC/MachineLocation.h"
25 #include "llvm/Target/TargetInstrInfo.h"
26
27 using namespace llvm;
28
NVPTXFrameLowering()29 NVPTXFrameLowering::NVPTXFrameLowering()
30 : TargetFrameLowering(TargetFrameLowering::StackGrowsUp, 8, 0) {}
31
hasFP(const MachineFunction & MF) const32 bool NVPTXFrameLowering::hasFP(const MachineFunction &MF) const { return true; }
33
emitPrologue(MachineFunction & MF,MachineBasicBlock & MBB) const34 void NVPTXFrameLowering::emitPrologue(MachineFunction &MF,
35 MachineBasicBlock &MBB) const {
36 if (MF.getFrameInfo()->hasStackObjects()) {
37 assert(&MF.front() == &MBB && "Shrink-wrapping not yet supported");
38 MachineInstr *MI = MBB.begin();
39 MachineRegisterInfo &MR = MF.getRegInfo();
40
41 // This instruction really occurs before first instruction
42 // in the BB, so giving it no debug location.
43 DebugLoc dl = DebugLoc();
44
45 // Emits
46 // mov %SPL, %depot;
47 // cvta.local %SP, %SPL;
48 // for local address accesses in MF.
49 bool Is64Bit =
50 static_cast<const NVPTXTargetMachine &>(MF.getTarget()).is64Bit();
51 unsigned CvtaLocalOpcode =
52 (Is64Bit ? NVPTX::cvta_local_yes_64 : NVPTX::cvta_local_yes);
53 unsigned MovDepotOpcode =
54 (Is64Bit ? NVPTX::MOV_DEPOT_ADDR_64 : NVPTX::MOV_DEPOT_ADDR);
55 if (!MR.use_empty(NVPTX::VRFrame)) {
56 // If %SP is not used, do not bother emitting "cvta.local %SP, %SPL".
57 MI = BuildMI(MBB, MI, dl,
58 MF.getSubtarget().getInstrInfo()->get(CvtaLocalOpcode),
59 NVPTX::VRFrame)
60 .addReg(NVPTX::VRFrameLocal);
61 }
62 BuildMI(MBB, MI, dl, MF.getSubtarget().getInstrInfo()->get(MovDepotOpcode),
63 NVPTX::VRFrameLocal)
64 .addImm(MF.getFunctionNumber());
65 }
66 }
67
emitEpilogue(MachineFunction & MF,MachineBasicBlock & MBB) const68 void NVPTXFrameLowering::emitEpilogue(MachineFunction &MF,
69 MachineBasicBlock &MBB) const {}
70
71 // This function eliminates ADJCALLSTACKDOWN,
72 // ADJCALLSTACKUP pseudo instructions
eliminateCallFramePseudoInstr(MachineFunction & MF,MachineBasicBlock & MBB,MachineBasicBlock::iterator I) const73 void NVPTXFrameLowering::eliminateCallFramePseudoInstr(
74 MachineFunction &MF, MachineBasicBlock &MBB,
75 MachineBasicBlock::iterator I) const {
76 // Simply discard ADJCALLSTACKDOWN,
77 // ADJCALLSTACKUP instructions.
78 MBB.erase(I);
79 }
80