//===-- AVRFixupKinds.h - AVR Specific Fixup Entries ------------*- 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
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_AVR_FIXUP_KINDS_H
#define LLVM_AVR_FIXUP_KINDS_H
#include "llvm/MC/MCFixup.h"
namespace llvm {
namespace AVR {
/// The set of supported fixups.
///
/// Although most of the current fixup types reflect a unique relocation
/// one can have multiple fixup types for a given relocation and thus need
/// to be uniquely named.
///
/// \note This table *must* be in the same order of
/// MCFixupKindInfo Infos[AVR::NumTargetFixupKinds]
/// in `AVRAsmBackend.cpp`.
enum Fixups {
/// A 32-bit AVR fixup.
fixup_32 = FirstTargetFixupKind,
/// A 7-bit PC-relative fixup for the family of conditional
/// branches which take 7-bit targets (BRNE,BRGT,etc).
fixup_7_pcrel,
/// A 12-bit PC-relative fixup for the family of branches
/// which take 12-bit targets (RJMP,RCALL,etc).
/// \note Although the fixup is labelled as 13 bits, it
/// is actually only encoded in 12. The reason for
/// The nonmenclature is that AVR branch targets are
/// rightshifted by 1, because instructions are always
/// aligned to 2 bytes, so the 0'th bit is always 0.
/// This way there is 13-bits of precision.
fixup_13_pcrel,
/// A 16-bit address.
fixup_16,
/// A 16-bit program memory address.
fixup_16_pm,
/// Replaces the 8-bit immediate with another value.
fixup_ldi,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the lower 8 bits of a 16-bit value (bits 0-7).
fixup_lo8_ldi,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a 16-bit value (bits 8-15).
fixup_hi8_ldi,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a 24-bit value (bits 16-23).
fixup_hh8_ldi,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a 32-bit value (bits 24-31).
fixup_ms8_ldi,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the lower 8 bits of a negated 16-bit value (bits 0-7).
fixup_lo8_ldi_neg,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a negated 16-bit value (bits 8-15).
fixup_hi8_ldi_neg,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a negated negated 24-bit value (bits 16-23).
fixup_hh8_ldi_neg,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a negated negated 32-bit value (bits 24-31).
fixup_ms8_ldi_neg,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the lower 8 bits of a 16-bit program memory address value (bits 0-7).
fixup_lo8_ldi_pm,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a 16-bit program memory address value (bits
/// 8-15).
fixup_hi8_ldi_pm,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a 24-bit program memory address value (bits
/// 16-23).
fixup_hh8_ldi_pm,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the lower 8 bits of a negated 16-bit program memory address value
/// (bits 0-7).
fixup_lo8_ldi_pm_neg,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a negated 16-bit program memory address value
/// (bits 8-15).
fixup_hi8_ldi_pm_neg,
/// Replaces the immediate operand of a 16-bit `Rd, K` instruction
/// with the upper 8 bits of a negated 24-bit program memory address value
/// (bits 16-23).
fixup_hh8_ldi_pm_neg,
/// A 22-bit fixup for the target of a `CALL k` or `JMP k` instruction.
fixup_call,
fixup_6,
/// A symbol+addr fixup for the `LDD <x>+<n>, <r>" family of instructions.
fixup_6_adiw,
fixup_lo8_ldi_gs,
fixup_hi8_ldi_gs,
fixup_8,
fixup_8_lo8,
fixup_8_hi8,
fixup_8_hlo8,
fixup_diff8,
fixup_diff16,
fixup_diff32,
fixup_lds_sts_16,
/// A 6-bit port address.
fixup_port6,
/// A 5-bit port address.
fixup_port5,
// Marker
LastTargetFixupKind,
NumTargetFixupKinds = LastTargetFixupKind - FirstTargetFixupKind
};
namespace fixups {
/// Adjusts the value of a branch target.
/// All branch targets in AVR are rightshifted by 1 to take advantage
/// of the fact that all instructions are aligned to addresses of size
/// 2, so bit 0 of an address is always 0. This gives us another bit
/// of precision.
/// \param [in,out] val The target to adjust.
template <typename T> inline void adjustBranchTarget(T &val) { val >>= 1; }
} // end of namespace fixups
}
} // end of namespace llvm::AVR
#endif // LLVM_AVR_FIXUP_KINDS_H