llvm-project/llvm/lib/Target/NVPTX/NVPTXFrameLowering.cpp

92 lines
3.4 KiB
C++

//=======- NVPTXFrameLowering.cpp - NVPTX Frame Information ---*- C++ -*-=====//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains the NVPTX implementation of TargetFrameLowering class.
//
//===----------------------------------------------------------------------===//
#include "NVPTXFrameLowering.h"
#include "NVPTX.h"
#include "NVPTXRegisterInfo.h"
#include "NVPTXSubtarget.h"
#include "NVPTXTargetMachine.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetInstrInfo.h"
#include "llvm/MC/MachineLocation.h"
using namespace llvm;
NVPTXFrameLowering::NVPTXFrameLowering()
: TargetFrameLowering(TargetFrameLowering::StackGrowsUp, Align(8), 0) {}
bool NVPTXFrameLowering::hasFP(const MachineFunction &MF) const { return true; }
void NVPTXFrameLowering::emitPrologue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
if (MF.getFrameInfo().hasStackObjects()) {
assert(&MF.front() == &MBB && "Shrink-wrapping not yet supported");
MachineInstr *MI = &MBB.front();
MachineRegisterInfo &MR = MF.getRegInfo();
// This instruction really occurs before first instruction
// in the BB, so giving it no debug location.
DebugLoc dl = DebugLoc();
// Emits
// mov %SPL, %depot;
// cvta.local %SP, %SPL;
// for local address accesses in MF.
bool Is64Bit =
static_cast<const NVPTXTargetMachine &>(MF.getTarget()).is64Bit();
unsigned CvtaLocalOpcode =
(Is64Bit ? NVPTX::cvta_local_yes_64 : NVPTX::cvta_local_yes);
unsigned MovDepotOpcode =
(Is64Bit ? NVPTX::MOV_DEPOT_ADDR_64 : NVPTX::MOV_DEPOT_ADDR);
if (!MR.use_empty(NVPTX::VRFrame)) {
// If %SP is not used, do not bother emitting "cvta.local %SP, %SPL".
MI = BuildMI(MBB, MI, dl,
MF.getSubtarget().getInstrInfo()->get(CvtaLocalOpcode),
NVPTX::VRFrame)
.addReg(NVPTX::VRFrameLocal);
}
BuildMI(MBB, MI, dl, MF.getSubtarget().getInstrInfo()->get(MovDepotOpcode),
NVPTX::VRFrameLocal)
.addImm(MF.getFunctionNumber());
}
}
StackOffset
NVPTXFrameLowering::getFrameIndexReference(const MachineFunction &MF, int FI,
Register &FrameReg) const {
const MachineFrameInfo &MFI = MF.getFrameInfo();
FrameReg = NVPTX::VRDepot;
return StackOffset::getFixed(MFI.getObjectOffset(FI) -
getOffsetOfLocalArea());
}
void NVPTXFrameLowering::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {}
// This function eliminates ADJCALLSTACKDOWN,
// ADJCALLSTACKUP pseudo instructions
MachineBasicBlock::iterator NVPTXFrameLowering::eliminateCallFramePseudoInstr(
MachineFunction &MF, MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
// Simply discard ADJCALLSTACKDOWN,
// ADJCALLSTACKUP instructions.
return MBB.erase(I);
}
TargetFrameLowering::DwarfFrameBase
NVPTXFrameLowering::getDwarfFrameBase(const MachineFunction &MF) const {
return {DwarfFrameBase::CFA, {0}};
}