ff171acf84
This change has 2 components: Target-independent: add a method getDwarfFrameBase to TargetFrameLowering. It describes how the Dwarf frame base will be encoded. That can be a register (the default), the CFA (which replaces NVPTX-specific logic in DwarfCompileUnit), or a DW_OP_WASM_location descriptr. WebAssembly: Allow WebAssemblyFunctionInfo::getFrameRegister to return the correct virtual register instead of FP32/SP32 after WebAssemblyReplacePhysRegs has run. Make WebAssemblyExplicitLocals store the local it allocates for the frame register. Use this local information to implement getDwarfFrameBase The result is that the DW_AT_frame_base attribute is correctly encoded for each subprogram, and each param and local variable has a correct DW_AT_location that uses DW_OP_fbreg to refer to the frame base. This is a reland of rG3a05c3969c18 with fixes for the expensive-checks and Windows builds Differential Revision: https://reviews.llvm.org/D71681
67 lines
2.6 KiB
C++
67 lines
2.6 KiB
C++
// WebAssemblyFrameLowering.h - TargetFrameLowering for WebAssembly -*- C++ -*-/
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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///
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/// \file
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/// This class implements WebAssembly-specific bits of
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/// TargetFrameLowering class.
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///
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYFRAMELOWERING_H
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#define LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYFRAMELOWERING_H
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#include "llvm/CodeGen/TargetFrameLowering.h"
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namespace llvm {
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class MachineFrameInfo;
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class WebAssemblyFrameLowering final : public TargetFrameLowering {
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public:
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/// Size of the red zone for the user stack (leaf functions can use this much
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/// space below the stack pointer without writing it back to __stack_pointer
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/// global).
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// TODO: (ABI) Revisit and decide how large it should be.
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static const size_t RedZoneSize = 128;
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WebAssemblyFrameLowering()
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: TargetFrameLowering(StackGrowsDown, /*StackAlignment=*/Align(16),
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/*LocalAreaOffset=*/0,
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/*TransientStackAlignment=*/Align(16),
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/*StackRealignable=*/true) {}
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MachineBasicBlock::iterator
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eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
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MachineBasicBlock::iterator I) const override;
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/// These methods insert prolog and epilog code into the function.
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void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
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void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
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bool hasFP(const MachineFunction &MF) const override;
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bool hasReservedCallFrame(const MachineFunction &MF) const override;
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DwarfFrameBase getDwarfFrameBase(const MachineFunction &MF) const override;
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bool needsPrologForEH(const MachineFunction &MF) const;
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/// Write SP back to __stack_pointer global.
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void writeSPToGlobal(unsigned SrcReg, MachineFunction &MF,
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MachineBasicBlock &MBB,
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MachineBasicBlock::iterator &InsertStore,
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const DebugLoc &DL) const;
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private:
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bool hasBP(const MachineFunction &MF) const;
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bool needsSPForLocalFrame(const MachineFunction &MF) const;
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bool needsSP(const MachineFunction &MF) const;
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bool needsSPWriteback(const MachineFunction &MF) const;
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};
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} // end namespace llvm
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#endif
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