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ab_riscv_primitives/instructions/rv32/zk/
zbkx.rs

1//! RV32 Zbkx extension
2
3#[cfg(test)]
4mod tests;
5
6use crate::instructions::Instruction;
7use crate::registers::general_purpose::Register;
8use ab_riscv_macros::instruction;
9use core::fmt;
10
11/// RISC-V RV32 Zbkx instruction (Crossbar permutations)
12#[instruction]
13#[derive(Debug, Clone, Copy)]
14#[derive_const(PartialEq, Eq)]
15pub enum Rv32ZbkxInstruction<Reg> {
16    Xperm4 { rd: Reg, rs1: Reg, rs2: Reg },
17    Xperm8 { rd: Reg, rs1: Reg, rs2: Reg },
18}
19
20#[instruction]
21const impl<Reg> Instruction for Rv32ZbkxInstruction<Reg>
22where
23    Reg: [const] Register<Type = u32>,
24{
25    type Reg = Reg;
26
27    #[inline(always)]
28    #[cfg_attr(feature = "no-panic", no_panic_const::no_panic(const))]
29    fn try_decode(instruction: u32) -> Option<Self> {
30        let opcode = (instruction & 0b111_1111) as u8;
31        let rd_bits = ((instruction >> 7) & 0x1f) as u8;
32        let funct3 = ((instruction >> 12) & 0b111) as u8;
33        let rs1_bits = ((instruction >> 15) & 0x1f) as u8;
34        let rs2_bits = ((instruction >> 20) & 0x1f) as u8;
35        let funct7 = ((instruction >> 25) & 0b111_1111) as u8;
36
37        match opcode {
38            0b011_0011 => {
39                let rd = Reg::from_bits(rd_bits)?;
40                let rs1 = Reg::from_bits(rs1_bits)?;
41                let rs2 = Reg::from_bits(rs2_bits)?;
42                match (funct3, funct7) {
43                    (0b010, 0b001_0100) => Some(Self::Xperm4 { rd, rs1, rs2 }),
44                    (0b100, 0b001_0100) => Some(Self::Xperm8 { rd, rs1, rs2 }),
45                    _ => None,
46                }
47            }
48            _ => None,
49        }
50    }
51
52    #[inline(always)]
53    fn alignment() -> u8 {
54        align_of::<u32>() as u8
55    }
56
57    #[inline(always)]
58    fn size(&self) -> u8 {
59        size_of::<u32>() as u8
60    }
61}
62
63#[instruction]
64impl<Reg> fmt::Display for Rv32ZbkxInstruction<Reg>
65where
66    Reg: fmt::Display,
67{
68    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
69        match self {
70            Self::Xperm4 { rd, rs1, rs2 } => write!(f, "xperm4 {rd}, {rs1}, {rs2}"),
71            Self::Xperm8 { rd, rs1, rs2 } => write!(f, "xperm8 {rd}, {rs1}, {rs2}"),
72        }
73    }
74}