charm 0.0.1

ARM assembler & disassembler generated from the ARM exploration tools.
Documentation
//! # TBNZ
//!
//! This instruction compares the value of a bit in a general-purpose register with zero, and conditionally branches to a label at a PC-relative offset if the comparison is not equal. This instruction provides a hint that this is not a subroutine call or return. This instruction does not affect condition flags.

#![allow(non_snake_case)]
#![allow(unused)]
use crate::error::Result;
use crate::utils::*;
use super::super::formatter::*;
use super::super::instruction::*;
use super::super::operand::*;
use super::super::consts::*;
use super::super::config::*;
use super::super::decoder::*;

// ---------------------------------------------------------------------------
// Iclass IclassTbnzOnlyTestbranch
// ---------------------------------------------------------------------------

/// Type that represents the IclassTbnzOnlyTestbranch instruction class.
pub(crate) struct IclassTbnzOnlyTestbranch;

impl IclassTbnzOnlyTestbranch {
    /// Tries to decode the instruction in `data`.
    pub(crate) fn decode(data: u32, decoder: &mut Decoder) -> Result<Instruction> {
        let b40 = (data >> 19) & 31;
        let b40_post = b40;
        let imm14 = (data >> 5) & 16383;
        let imm14_post = imm14;
        let Rt = (data >> 0) & 31;
        let Rt_post = Rt;
        let field_28 = (data >> 26) & 7;
        let field_28_post = field_28;
        let op = (data >> 24) & 1;
        let op_post = op;
        let b5 = (data >> 31) & 1;
        let b5_post = b5;
        let field_25 = (data >> 25) & 1;
        let field_25_post = field_25;
        let field_30 = (data >> 29) & 3;
        let field_30_post = field_30;


        return TbnzOnlyTestbranch::decode(data as u32, decoder);

        unreachable!()
    }
}

/// None-bit encoding.
///
/// # Encoding
///
/// <table style="font-family: courier, monospace">
///     <tr>
///         <td style="border: none">31</td>
///         <td style="border: none">30</td>
///         <td style="border: none">29</td>
///         <td style="border: none">28</td>
///         <td style="border: none">27</td>
///         <td style="border: none">26</td>
///         <td style="border: none">25</td>
///         <td style="border: none">24</td>
///         <td style="border: none">23</td>
///         <td style="border: none">22</td>
///         <td style="border: none">21</td>
///         <td style="border: none">20</td>
///         <td style="border: none">19</td>
///         <td style="border: none">18</td>
///         <td style="border: none">17</td>
///         <td style="border: none">16</td>
///         <td style="border: none">15</td>
///         <td style="border: none">14</td>
///         <td style="border: none">13</td>
///         <td style="border: none">12</td>
///         <td style="border: none">11</td>
///         <td style="border: none">10</td>
///         <td style="border: none">9</td>
///         <td style="border: none">8</td>
///         <td style="border: none">7</td>
///         <td style="border: none">6</td>
///         <td style="border: none">5</td>
///         <td style="border: none">4</td>
///         <td style="border: none">3</td>
///         <td style="border: none">2</td>
///         <td style="border: none">1</td>
///         <td style="border: none">0</td>
///     </tr>
///     <tr>
/// <td style="text-align: center" colspan="1">b5</td>
///          <td style="text-align: center; border-right: none" colspan="1">0</td>
///          <td style="text-align: center; border-left: none" colspan="1">1</td>
///          <td style="text-align: center; border-right: none" colspan="1">1</td>
///          <td style="text-align: center; border-left: none; border-right: none" colspan="1">0</td>
///          <td style="text-align: center; border-left: none" colspan="1">1</td>
///          <td style="text-align: center; border-right: none" colspan="1">1</td>
///          <td style="text-align: center; border-right: none" colspan="1">1</td>
/// <td style="text-align: center" colspan="5">b40</td>
/// <td style="text-align: center" colspan="14">imm14</td>
/// <td style="text-align: center" colspan="5">Rt</td>
///     </tr>
///     <tr>
/// <td style="text-align: center; border: none" colspan="1"></td>
/// <td style="text-align: center; border: none" colspan="2"></td>
/// <td style="text-align: center; border: none" colspan="3"></td>
/// <td style="text-align: center; border: none" colspan="1"></td>
/// <td style="text-align: center; border: none" colspan="1">op</td>
/// <td style="text-align: center; border: none" colspan="5"></td>
/// <td style="text-align: center; border: none" colspan="14"></td>
/// <td style="text-align: center; border: none" colspan="5"></td>
///     </tr>
/// </table>
pub struct TbnzOnlyTestbranch;

impl TbnzOnlyTestbranch {
    /// Returns the instruction mnemonic.
    pub fn mnemonic(_instr: &Instruction) -> Mnemonic {
        Mnemonic::TBNZ
    }

    /// Returns the instruction size.
    pub fn size(_instr: &Instruction) -> usize {
        4
    }

    /// Decodes the instruction in `data`.
    pub fn decode(data: u32, decoder: &mut Decoder) -> Result<Instruction> {
        // Fields are extracted from the input value.
        let b5 = (data >> 31) & 1;
        let b5_post = b5;
        let b40 = (data >> 19) & 31;
        let b40_post = b40;
        let imm14 = (data >> 5) & 16383;
        let imm14_post = imm14;
        let Rt = (data >> 0) & 31;
        let Rt_post = Rt;
        

        // Operand values are computed from the base fields.
        let Rt_post = Rt;
        let op_0 = match b5 {0 => Register::aarch32(Rt_post, false)?,1 => Register::aarch64(Rt_post, false)?,
            _ => todo!(),
        };
        let b40_b5_post = (b5 << 5) | b40;
        let op_1 = b40_b5_post as u32;
        let imm14_post = ((((imm14) as i64) * 4) << 48) >> 48;
        let op_2 = Label::decode(imm14_post.into());

        // Instruction creation from the operands.
        let mut instr = Instruction::builder(Code::TBNZ_only_testbranch)
            .operand(0, op_0)?
            .operand(1, op_1)?
            .operand(2, op_2)?
            .build();
        
        // For encodings using labels, we check if we are decoding instruction blocks,
        // which requires labels to be tracked.
        if decoder.block_decoding {
            // TODO: handle addition
            // The label target is computed from the value stored in the corresponding operand.
            let pc = match instr.op2().as_label()? {
                Label::Label(imm) => (decoder.pc as i128 + imm as i128) as u64,
                _ => unreachable!(),
            };
            // The label target is added to the decoder hashset and will be used
            // to see if labels should be added in the resulting decoded instructions block.
            decoder.labels.insert(pc);
            // The operand is also replaced by a named label that references the label
            // that was added to the hashset.
            instr.set_op(2, Label::LabelName(pc as u64))?;
        }
        
        Ok(instr)
    }

    /// Encodes the instruction into `buf`.
    pub fn encode(instr: &Instruction, buf: &mut Vec<u8>) -> Result<usize> {
        // Retrieve all operand values.
        let Rt_pre = instr.op0().as_register()?.encode();
        let b40_b5_pre = instr.op1().as_unsigned_immediate()? as u32;
        let imm14_pre = instr.op2().as_label()?.encode()?;

        // Compute all instruction fields from the operand values.
        let Rt = (Rt_pre & 31);
        let b40_b5_pre = b40_b5_pre;
        let b40 = (b40_b5_pre & 31);
        let b5 = (b40_b5_pre >> 5) & 1;
        let imm14_pre = ((imm14_pre) / 4) as u32;
        let imm14 = (imm14_pre & 16383);

        // Add all fields to the base instruction encoding.
        let mut instr: u32 = 0b00110111000000000000000000000000;
        instr |= (Rt & 31) << 0;
        instr |= (b40 & 31) << 19;
        instr |= (b5 & 1) << 31;
        instr |= (imm14 & 16383) << 5;

        let bytes = instr.to_le_bytes();
        let len = bytes.len();
        buf.extend(bytes);
        Ok(len)
    }

    /// Encode an instruction part of an instruction block into `buf`.
    pub fn encode_block(instr: &mut Instruction, buf: &mut Vec<u8>, labels: &std::collections::HashMap<u64, u64>) -> Result<usize> {
        if let Label::LabelName(label_name) = instr.op2().as_label()? {
            if let Some(label_pc) = labels.get(&label_name) {
                // TODO: handle addition
                let pc = *label_pc as i128 - instr.pc as i128;
                instr.set_op(2, Label::decode(pc as i64))?;
            } else {
                // TODO: handle addition
                let pc = label_name as i128 - instr.pc as i128;
                instr.set_op(2, Label::decode(pc as i64))?;
            }
        }
        Self::encode(instr, buf)
    }
    
    /// Verifies that operand #0 is valid.
    pub fn check_op0(instr: &Instruction, op: &Operand) -> Result<()> {
        if let Operand::Register(r) = op {
            if *r == Register::SP || *r == Register::WSP {
                todo!()
            }
            return Ok(())
        }
        todo!()
    }
    
    /// Verifies that operand #1 is valid.
    pub fn check_op1(instr: &Instruction, op: &Operand) -> Result<()> {
        if let Operand::UnsignedImmediate(i) = op {
            if !(0..=63).contains(i) {
                todo!()
            }
            return Ok(())
        }
        todo!()
    }
    
    /// Verifies that operand #2 is valid.
    pub fn check_op2(instr: &Instruction, op: &Operand) -> Result<()> {
        if let Operand::Label(Label::LabelName(_)) = op {
            return Ok(())
        }
        if let Operand::Label(Label::Label(i)) = op {
            if !(-32768..=32768).contains(i) {
                todo!()
            }
            return Ok(())
        }
        todo!()
    }
    
    /// Verifies that operand #3 is valid.
    pub fn check_op3(instr: &Instruction, op: &Operand) -> Result<()> {
        todo!()
    }
    
    /// Verifies that operand #4 is valid.
    pub fn check_op4(instr: &Instruction, op: &Operand) -> Result<()> {
        todo!()
    }
    
    /// Verifies that operand #5 is valid.
    pub fn check_op5(instr: &Instruction, op: &Operand) -> Result<()> {
        todo!()
    }
    
    /// Verifies that operand #6 is valid.
    pub fn check_op6(instr: &Instruction, op: &Operand) -> Result<()> {
        todo!()
    }

    /// Formats the instruction.
    pub fn format(instr: &Instruction, fmt: &mut impl Formatter, output: &mut impl FormatterOutput, config: &Config) -> Result<()> {
        fmt.format_mnemonic(output, &config.global, &config.instructions.tbnz_only_testbranch, instr)?;
        fmt.format_punctuation(output, &config.global, &config.instructions.tbnz_only_testbranch, instr, FormatterTextKind::Space)?;
        fmt.format_operand(output, &config.global, &config.instructions.tbnz_only_testbranch, instr, 0)?;
        fmt.format_punctuation(output, &config.global, &config.instructions.tbnz_only_testbranch, instr, FormatterTextKind::Comma)?;
        fmt.format_punctuation(output, &config.global, &config.instructions.tbnz_only_testbranch, instr, FormatterTextKind::NumSign)?;
        fmt.format_operand(output, &config.global, &config.instructions.tbnz_only_testbranch, instr, 1)?;
        fmt.format_punctuation(output, &config.global, &config.instructions.tbnz_only_testbranch, instr, FormatterTextKind::Comma)?;
        fmt.format_operand(output, &config.global, &config.instructions.tbnz_only_testbranch, instr, 2)?;
        Ok(())
    }
}

/// Type that represents alias identifiers for [`TbnzOnlyTestbranch`].
#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Debug, Hash)]
pub enum TbnzOnlyTestbranchAliases {
    None,
}