10b57cec5SDimitry Andric // WebAssemblyFrameLowering.h - TargetFrameLowering for WebAssembly -*- C++ -*-/ 20b57cec5SDimitry Andric // 30b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 40b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 50b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 60b57cec5SDimitry Andric // 70b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 80b57cec5SDimitry Andric /// 90b57cec5SDimitry Andric /// \file 100b57cec5SDimitry Andric /// This class implements WebAssembly-specific bits of 110b57cec5SDimitry Andric /// TargetFrameLowering class. 120b57cec5SDimitry Andric /// 130b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 140b57cec5SDimitry Andric 150b57cec5SDimitry Andric #ifndef LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYFRAMELOWERING_H 160b57cec5SDimitry Andric #define LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYFRAMELOWERING_H 170b57cec5SDimitry Andric 180b57cec5SDimitry Andric #include "llvm/CodeGen/TargetFrameLowering.h" 190b57cec5SDimitry Andric 200b57cec5SDimitry Andric namespace llvm { 210b57cec5SDimitry Andric 220b57cec5SDimitry Andric class WebAssemblyFrameLowering final : public TargetFrameLowering { 230b57cec5SDimitry Andric public: 240b57cec5SDimitry Andric /// Size of the red zone for the user stack (leaf functions can use this much 250b57cec5SDimitry Andric /// space below the stack pointer without writing it back to __stack_pointer 260b57cec5SDimitry Andric /// global). 270b57cec5SDimitry Andric // TODO: (ABI) Revisit and decide how large it should be. 280b57cec5SDimitry Andric static const size_t RedZoneSize = 128; 290b57cec5SDimitry Andric WebAssemblyFrameLowering()300b57cec5SDimitry Andric WebAssemblyFrameLowering() 318bcb0991SDimitry Andric : TargetFrameLowering(StackGrowsDown, /*StackAlignment=*/Align(16), 320b57cec5SDimitry Andric /*LocalAreaOffset=*/0, 338bcb0991SDimitry Andric /*TransientStackAlignment=*/Align(16), 340b57cec5SDimitry Andric /*StackRealignable=*/true) {} 350b57cec5SDimitry Andric 360b57cec5SDimitry Andric MachineBasicBlock::iterator 370b57cec5SDimitry Andric eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB, 380b57cec5SDimitry Andric MachineBasicBlock::iterator I) const override; 390b57cec5SDimitry Andric 400b57cec5SDimitry Andric /// These methods insert prolog and epilog code into the function. 410b57cec5SDimitry Andric void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override; 420b57cec5SDimitry Andric void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override; 430b57cec5SDimitry Andric 440b57cec5SDimitry Andric bool hasFP(const MachineFunction &MF) const override; 450b57cec5SDimitry Andric bool hasReservedCallFrame(const MachineFunction &MF) const override; 46fe6060f1SDimitry Andric bool isSupportedStackID(TargetStackID::Value ID) const override; 475ffd83dbSDimitry Andric DwarfFrameBase getDwarfFrameBase(const MachineFunction &MF) const override; 480b57cec5SDimitry Andric 490b57cec5SDimitry Andric bool needsPrologForEH(const MachineFunction &MF) const; 500b57cec5SDimitry Andric 510b57cec5SDimitry Andric /// Write SP back to __stack_pointer global. 520b57cec5SDimitry Andric void writeSPToGlobal(unsigned SrcReg, MachineFunction &MF, 530b57cec5SDimitry Andric MachineBasicBlock &MBB, 540b57cec5SDimitry Andric MachineBasicBlock::iterator &InsertStore, 550b57cec5SDimitry Andric const DebugLoc &DL) const; 560b57cec5SDimitry Andric 57fe6060f1SDimitry Andric // Returns the index of the WebAssembly local to which the stack object 58*bdd1243dSDimitry Andric // FrameIndex in MF should be allocated, or std::nullopt. 59*bdd1243dSDimitry Andric static std::optional<unsigned> getLocalForStackObject(MachineFunction &MF, 60fe6060f1SDimitry Andric int FrameIndex); 61fe6060f1SDimitry Andric 625ffd83dbSDimitry Andric static unsigned getSPReg(const MachineFunction &MF); 635ffd83dbSDimitry Andric static unsigned getFPReg(const MachineFunction &MF); 645ffd83dbSDimitry Andric static unsigned getOpcConst(const MachineFunction &MF); 655ffd83dbSDimitry Andric static unsigned getOpcAdd(const MachineFunction &MF); 665ffd83dbSDimitry Andric static unsigned getOpcSub(const MachineFunction &MF); 675ffd83dbSDimitry Andric static unsigned getOpcAnd(const MachineFunction &MF); 685ffd83dbSDimitry Andric static unsigned getOpcGlobGet(const MachineFunction &MF); 695ffd83dbSDimitry Andric static unsigned getOpcGlobSet(const MachineFunction &MF); 705ffd83dbSDimitry Andric 710b57cec5SDimitry Andric private: 720b57cec5SDimitry Andric bool hasBP(const MachineFunction &MF) const; 730b57cec5SDimitry Andric bool needsSPForLocalFrame(const MachineFunction &MF) const; 740b57cec5SDimitry Andric bool needsSP(const MachineFunction &MF) const; 750b57cec5SDimitry Andric bool needsSPWriteback(const MachineFunction &MF) const; 760b57cec5SDimitry Andric }; 770b57cec5SDimitry Andric 780b57cec5SDimitry Andric } // end namespace llvm 790b57cec5SDimitry Andric 800b57cec5SDimitry Andric #endif 81