llvm-project/llvm/lib/Target/ARM/MCTargetDesc/ARMUnwindOpAsm.h

92 lines
2.5 KiB
C++

//===-- ARMUnwindOpAsm.h - ARM Unwind Opcodes Assembler ---------*- 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 file declares the unwind opcode assmebler for ARM exception handling
// table.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_TARGET_ARM_MCTARGETDESC_ARMUNWINDOPASM_H
#define LLVM_LIB_TARGET_ARM_MCTARGETDESC_ARMUNWINDOPASM_H
#include "llvm/ADT/SmallVector.h"
#include <cstddef>
#include <cstdint>
namespace llvm {
class MCSymbol;
class UnwindOpcodeAssembler {
private:
SmallVector<uint8_t, 32> Ops;
SmallVector<unsigned, 8> OpBegins;
bool HasPersonality = false;
public:
UnwindOpcodeAssembler() {
OpBegins.push_back(0);
}
/// Reset the unwind opcode assembler.
void Reset() {
Ops.clear();
OpBegins.clear();
OpBegins.push_back(0);
HasPersonality = false;
}
/// Set the personality
void setPersonality(const MCSymbol *Per) {
HasPersonality = true;
}
/// Emit unwind opcodes for .save directives
void EmitRegSave(uint32_t RegSave);
/// Emit unwind opcodes for .vsave directives
void EmitVFPRegSave(uint32_t VFPRegSave);
/// Emit unwind opcodes to copy address from source register to $sp.
void EmitSetSP(uint16_t Reg);
/// Emit unwind opcodes to add $sp with an offset.
void EmitSPOffset(int64_t Offset);
/// Emit unwind raw opcodes
void EmitRaw(const SmallVectorImpl<uint8_t> &Opcodes) {
Ops.insert(Ops.end(), Opcodes.begin(), Opcodes.end());
OpBegins.push_back(OpBegins.back() + Opcodes.size());
}
/// Finalize the unwind opcode sequence for EmitBytes()
void Finalize(unsigned &PersonalityIndex,
SmallVectorImpl<uint8_t> &Result);
private:
void EmitInt8(unsigned Opcode) {
Ops.push_back(Opcode & 0xff);
OpBegins.push_back(OpBegins.back() + 1);
}
void EmitInt16(unsigned Opcode) {
Ops.push_back((Opcode >> 8) & 0xff);
Ops.push_back(Opcode & 0xff);
OpBegins.push_back(OpBegins.back() + 2);
}
void EmitBytes(const uint8_t *Opcode, size_t Size) {
Ops.insert(Ops.end(), Opcode, Opcode + Size);
OpBegins.push_back(OpBegins.back() + Size);
}
};
} // end namespace llvm
#endif // LLVM_LIB_TARGET_ARM_MCTARGETDESC_ARMUNWINDOPASM_H