ab_riscv_interpreter/
zicond.rs

1//! Zicond extension
2
3#[cfg(test)]
4mod tests;
5
6use crate::{
7    ExecutableInstruction, ExecutableInstructionCsr, ExecutableInstructionOperands, ExecutionError,
8    ExecutionResult, FetchInstructionResult, InstructionFetcher, OpaqueThreadedExecutionResult,
9    RegisterFile, Rs1Rs2OperandValues, Rs1Rs2Operands, ThreadedExecutableInstruction,
10    ThreadedExecutionResult,
11};
12use ab_riscv_macros::instruction_execution;
13use ab_riscv_primitives::prelude::*;
14
15#[instruction_execution]
16const impl<Reg, Hart> ExecutableInstructionOperands for ZicondInstruction<Hart>
17where
18    Reg: Register,
19    Hart: HartConfig<Reg = Reg>,
20{
21}
22
23#[instruction_execution]
24const impl<Reg, Hart, Env> ExecutableInstructionCsr<Env> for ZicondInstruction<Hart>
25where
26    Reg: Register,
27    Hart: HartConfig<Reg = Reg>,
28{
29}
30
31#[instruction_execution]
32const impl<Reg, Hart, Regs, Env, Memory, PC> ExecutableInstruction<Regs, Env, Memory, PC>
33    for ZicondInstruction<Hart>
34where
35    Reg: [const] Register,
36    Hart: HartConfig<Reg = Reg>,
37    Regs: [const] RegisterFile<Reg>,
38{
39    #[inline(always)]
40    #[cfg_attr(feature = "no-panic", no_panic_const::no_panic(const))]
41    fn execute(
42        self,
43        Rs1Rs2OperandValues {
44            rs1_value,
45            rs2_value,
46        }: Rs1Rs2OperandValues<Reg::Type>,
47        _regs: &mut Regs,
48        _env: &mut Env,
49        _memory: &mut Memory,
50        _program_counter: &PC,
51    ) -> ExecutionResult<Reg> {
52        match self {
53            // Conditional zero, equal to zero.
54            //
55            // rd = (rs2 == 0) ? 0 : rs1
56            Self::CzeroEqz { rd, rs1: _, rs2: _ } => {
57                let condition = rs2_value;
58                let src = rs1_value;
59                let result = if condition == Reg::Type::from(0u8) {
60                    Reg::Type::from(0u8)
61                } else {
62                    src
63                };
64                ExecutionResult::Continue { rd, value: result }
65            }
66
67            // Conditional zero, nonzero.
68            //
69            // rd = (rs2 != 0) ? 0 : rs1
70            Self::CzeroNez { rd, rs1: _, rs2: _ } => {
71                let condition = rs2_value;
72                let src = rs1_value;
73                let result = if condition == Reg::Type::from(0u8) {
74                    src
75                } else {
76                    Reg::Type::from(0u8)
77                };
78                ExecutionResult::Continue { rd, value: result }
79            }
80        }
81    }
82}
ab_riscv_interpreter/zicond.rs

ab_riscv_interpreter/
zicond.rs
