1 //===-- RISCVFrameLowering.h - Define frame lowering for RISC-V -*- C++ -*-===// 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 // This class implements RISC-V specific bits of TargetFrameLowering class. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_LIB_TARGET_RISCV_RISCVFRAMELOWERING_H 14 #define LLVM_LIB_TARGET_RISCV_RISCVFRAMELOWERING_H 15 16 #include "llvm/CodeGen/TargetFrameLowering.h" 17 #include "llvm/Support/TypeSize.h" 18 19 namespace llvm { 20 class RISCVSubtarget; 21 22 class RISCVFrameLowering : public TargetFrameLowering { 23 public: 24 explicit RISCVFrameLowering(const RISCVSubtarget &STI); 25 26 void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override; 27 void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override; 28 29 uint64_t getStackSizeWithRVVPadding(const MachineFunction &MF) const; 30 31 StackOffset getFrameIndexReference(const MachineFunction &MF, int FI, 32 Register &FrameReg) const override; 33 34 void determineCalleeSaves(MachineFunction &MF, BitVector &SavedRegs, 35 RegScavenger *RS) const override; 36 37 void processFunctionBeforeFrameFinalized(MachineFunction &MF, 38 RegScavenger *RS) const override; 39 40 bool hasFP(const MachineFunction &MF) const override; 41 42 bool hasBP(const MachineFunction &MF) const; 43 44 bool hasReservedCallFrame(const MachineFunction &MF) const override; 45 MachineBasicBlock::iterator 46 eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB, 47 MachineBasicBlock::iterator MI) const override; 48 bool spillCalleeSavedRegisters(MachineBasicBlock &MBB, 49 MachineBasicBlock::iterator MI, 50 ArrayRef<CalleeSavedInfo> CSI, 51 const TargetRegisterInfo *TRI) const override; 52 bool 53 restoreCalleeSavedRegisters(MachineBasicBlock &MBB, 54 MachineBasicBlock::iterator MI, 55 MutableArrayRef<CalleeSavedInfo> CSI, 56 const TargetRegisterInfo *TRI) const override; 57 58 // Get the first stack adjustment amount for SplitSPAdjust. 59 // Return 0 if we don't want to split the SP adjustment in prologue and 60 // epilogue. 61 uint64_t getFirstSPAdjustAmount(const MachineFunction &MF) const; 62 63 bool canUseAsPrologue(const MachineBasicBlock &MBB) const override; 64 bool canUseAsEpilogue(const MachineBasicBlock &MBB) const override; 65 66 bool enableShrinkWrapping(const MachineFunction &MF) const override; 67 68 bool isSupportedStackID(TargetStackID::Value ID) const override; 69 TargetStackID::Value getStackIDForScalableVectors() const override; 70 71 bool isStackIdSafeForLocalArea(unsigned StackId) const override { 72 // We don't support putting RISC-V Vector objects into the pre-allocated 73 // local frame block at the moment. 74 return StackId != TargetStackID::ScalableVector; 75 } 76 77 protected: 78 const RISCVSubtarget &STI; 79 80 private: 81 void determineFrameLayout(MachineFunction &MF) const; 82 void adjustStackForRVV(MachineFunction &MF, MachineBasicBlock &MBB, 83 MachineBasicBlock::iterator MBBI, const DebugLoc &DL, 84 int64_t Amount, MachineInstr::MIFlag Flag) const; 85 std::pair<int64_t, Align> 86 assignRVVStackObjectOffsets(MachineFunction &MF) const; 87 }; 88 } // namespace llvm 89 #endif 90