ab_riscv_primitives/instructions/
zawrs.rs

1//! Zawrs extension
2
3#[cfg(test)]
4mod tests;
5
6use crate::hart::HartConfig;
7use crate::instructions::{ImplementedExtension, Instruction, IsaExtension};
8use crate::registers::general_purpose::Register;
9use ab_riscv_macros::instruction;
10use core::fmt;
11
12/// RISC-V Zawrs instruction (Wait-on-Reservation-Set)
13#[instruction]
14#[derive(Debug, Clone, Copy)]
15#[derive_const(PartialEq, Eq)]
16pub enum ZawrsInstruction<Hart>
17where
18    Hart: HartConfig,
19{
20    /// Wait-on-Reservation-Set, no timeout
21    WrsNto,
22    /// Wait-on-Reservation-Set, short timeout
23    WrsSto,
24}
25
26#[instruction]
27const impl<Reg, Hart> Instruction for ZawrsInstruction<Hart>
28where
29    Reg: [const] Register,
30    Hart: [const] HartConfig<Reg = Reg>,
31{
32    const OWN_ISA_EXTENSIONS: &'static [IsaExtension] = &[IsaExtension::new("zawrs", 1, 0)];
33
34    const ALIGNMENT: u8 = align_of::<u32>() as u8;
35
36    type Hart = Hart;
37
38    #[inline(always)]
39    #[cfg_attr(feature = "no-panic", no_panic_const::no_panic(const))]
40    fn try_decode(instruction: u32) -> Option<Self> {
41        let opcode = (instruction & 0b111_1111) as u8;
42        let rd_bits = ((instruction >> 7) & 0x1f) as u8;
43        let funct3 = ((instruction >> 12) & 0b111) as u8;
44        let rs1_bits = ((instruction >> 15) & 0x1f) as u8;
45        let imm = (instruction >> 20) & 0xfff;
46
47        match (opcode, funct3, rd_bits, rs1_bits, imm) {
48            (0b111_0011, 0b000, 0, 0, 0x00d) => Some(Self::WrsNto),
49            (0b111_0011, 0b000, 0, 0, 0x01d) => Some(Self::WrsSto),
50            _ => None,
51        }
52    }
53
54    #[inline(always)]
55    fn size(&self) -> u8 {
56        size_of::<u32>() as u8
57    }
58}
59
60#[instruction]
61impl<Reg, Hart> fmt::Display for ZawrsInstruction<Hart>
62where
63    Reg: fmt::Display,
64    Hart: HartConfig<Reg = Reg>,
65{
66    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
67        match self {
68            Self::WrsNto => write!(f, "wrs.nto"),
69            Self::WrsSto => write!(f, "wrs.sto"),
70        }
71    }
72}
ab_riscv_primitives/instructions/zawrs.rs

ab_riscv_primitives/instructions/
zawrs.rs
