llvm-project/llvm/lib/Target/RISCV/RISCVFrameLowering.h
Alex Rønne Petersen ad4a582fd9
[llvm] Consistently respect naked fn attribute in TargetFrameLowering::hasFP() (#106014)
Some targets (e.g. PPC and Hexagon) already did this. I think it's best
to do this consistently so that frontend authors don't run into
inconsistent results when they emit `naked` functions. For example, in
Zig, we had to change our emit code to also set `frame-pointer=none` to
get reliable results across targets.

Note: I don't have commit access.
2024-10-18 09:35:42 +04:00

103 lines
4.3 KiB
C++

//===-- RISCVFrameLowering.h - Define frame lowering for RISC-V -*- 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 class implements RISC-V specific bits of TargetFrameLowering class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_TARGET_RISCV_RISCVFRAMELOWERING_H
#define LLVM_LIB_TARGET_RISCV_RISCVFRAMELOWERING_H
#include "llvm/CodeGen/TargetFrameLowering.h"
#include "llvm/Support/TypeSize.h"
namespace llvm {
class RISCVSubtarget;
class RISCVFrameLowering : public TargetFrameLowering {
public:
explicit RISCVFrameLowering(const RISCVSubtarget &STI);
void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
uint64_t getStackSizeWithRVVPadding(const MachineFunction &MF) const;
StackOffset getFrameIndexReference(const MachineFunction &MF, int FI,
Register &FrameReg) const override;
void determineCalleeSaves(MachineFunction &MF, BitVector &SavedRegs,
RegScavenger *RS) const override;
void processFunctionBeforeFrameFinalized(MachineFunction &MF,
RegScavenger *RS) const override;
bool hasBP(const MachineFunction &MF) const;
bool hasReservedCallFrame(const MachineFunction &MF) const override;
MachineBasicBlock::iterator
eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI) const override;
bool assignCalleeSavedSpillSlots(MachineFunction &MF,
const TargetRegisterInfo *TRI,
std::vector<CalleeSavedInfo> &CSI,
unsigned &MinCSFrameIndex,
unsigned &MaxCSFrameIndex) const override;
bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
ArrayRef<CalleeSavedInfo> CSI,
const TargetRegisterInfo *TRI) const override;
bool
restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
MutableArrayRef<CalleeSavedInfo> CSI,
const TargetRegisterInfo *TRI) const override;
// Get the first stack adjustment amount for SplitSPAdjust.
// Return 0 if we don't want to split the SP adjustment in prologue and
// epilogue.
uint64_t getFirstSPAdjustAmount(const MachineFunction &MF) const;
bool canUseAsPrologue(const MachineBasicBlock &MBB) const override;
bool canUseAsEpilogue(const MachineBasicBlock &MBB) const override;
bool enableShrinkWrapping(const MachineFunction &MF) const override;
bool isSupportedStackID(TargetStackID::Value ID) const override;
TargetStackID::Value getStackIDForScalableVectors() const override;
bool isStackIdSafeForLocalArea(unsigned StackId) const override {
// We don't support putting RISC-V Vector objects into the pre-allocated
// local frame block at the moment.
return StackId != TargetStackID::ScalableVector;
}
protected:
const RISCVSubtarget &STI;
bool hasFPImpl(const MachineFunction &MF) const override;
private:
void determineFrameLayout(MachineFunction &MF) const;
void adjustStackForRVV(MachineFunction &MF, MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI, const DebugLoc &DL,
int64_t Amount, MachineInstr::MIFlag Flag) const;
void emitCalleeSavedRVVPrologCFI(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
bool HasFP) const;
void deallocateStack(MachineFunction &MF, MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI, const DebugLoc &DL,
uint64_t StackSize, int64_t CFAOffset) const;
std::pair<int64_t, Align>
assignRVVStackObjectOffsets(MachineFunction &MF) const;
};
} // namespace llvm
#endif