// WebAssemblyFrameLowering.h - TargetFrameLowering for WebAssembly -*- 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 // //===----------------------------------------------------------------------===// /// /// \file /// This class implements WebAssembly-specific bits of /// TargetFrameLowering class. /// //===----------------------------------------------------------------------===// #ifndef LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYFRAMELOWERING_H #define LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYFRAMELOWERING_H #include "llvm/CodeGen/TargetFrameLowering.h" namespace llvm { class WebAssemblyFrameLowering final : public TargetFrameLowering { public: /// Size of the red zone for the user stack (leaf functions can use this much /// space below the stack pointer without writing it back to __stack_pointer /// global). // TODO: (ABI) Revisit and decide how large it should be. static const size_t RedZoneSize = 128; WebAssemblyFrameLowering() : TargetFrameLowering(StackGrowsDown, /*StackAlignment=*/Align(16), /*LocalAreaOffset=*/0, /*TransientStackAlignment=*/Align(16), /*StackRealignable=*/true) {} MachineBasicBlock::iterator eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB, MachineBasicBlock::iterator I) const override; /// These methods insert prolog and epilog code into the function. void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override; void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override; bool hasFP(const MachineFunction &MF) const override; bool hasReservedCallFrame(const MachineFunction &MF) const override; DwarfFrameBase getDwarfFrameBase(const MachineFunction &MF) const override; bool needsPrologForEH(const MachineFunction &MF) const; /// Write SP back to __stack_pointer global. void writeSPToGlobal(unsigned SrcReg, MachineFunction &MF, MachineBasicBlock &MBB, MachineBasicBlock::iterator &InsertStore, const DebugLoc &DL) const; static unsigned getSPReg(const MachineFunction &MF); static unsigned getFPReg(const MachineFunction &MF); static unsigned getOpcConst(const MachineFunction &MF); static unsigned getOpcAdd(const MachineFunction &MF); static unsigned getOpcSub(const MachineFunction &MF); static unsigned getOpcAnd(const MachineFunction &MF); static unsigned getOpcGlobGet(const MachineFunction &MF); static unsigned getOpcGlobSet(const MachineFunction &MF); private: bool hasBP(const MachineFunction &MF) const; bool needsSPForLocalFrame(const MachineFunction &MF) const; bool needsSP(const MachineFunction &MF) const; bool needsSPWriteback(const MachineFunction &MF) const; }; } // end namespace llvm #endif |