liftoff

.gitignore

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+/target

Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "riscv_interpreter"
+version = "0.1.0"

Cargo.toml

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+[package]
+name = "riscv_interpreter"
+version = "0.1.0"
+edition = "2021"

src/env.rs

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+
+
+pub enum Env {}

src/err.rs

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+use std::fmt::{self, Display, Formatter};
+
+pub enum SyntaxErr {
+    TraillingComma,
+    UnmatchedParen,
+}
+
+impl Display for SyntaxErr {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            SyntaxErr::TraillingComma => write!(f, "trailling comma"),
+            SyntaxErr::UnmatchedParen => write!(f, "unmatched parenthesis"),
+        }
+    }
+}
+
+pub enum RuntimeErr {
+    InvalidRegister(String),
+    UnexpectedImmediate,
+    UnexpectedRegister,
+    InvalidOp(String),
+    InvalidOpArity(String, usize, usize),
+}
+
+impl Display for RuntimeErr {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            RuntimeErr::InvalidRegister(reg) => write!(f, "invalid register {}", reg),
+            RuntimeErr::UnexpectedImmediate => write!(f, "unexpected immediate"),
+            RuntimeErr::UnexpectedRegister => write!(f, "unexpected register"),
+            RuntimeErr::InvalidOp(op) => write!(f, "invalid operation {}", op),
+            RuntimeErr::InvalidOpArity(op, expected, actual) => write!(
+                f,
+                "invalid operation arity {} expected {} got {}",
+                op, expected, actual
+            ),
+        }
+    }
+}

src/lib.rs

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+pub mod env;
+pub mod err;
+pub mod parser;

src/main.rs

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+fn main() {
+    println!("Hello, world!");
+}

src/parser.rs

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+pub enum Expr {
+    /// 1, 2, -1
+    Immediate(i64),
+    /// zero, r1, pc
+    Register(String),
+    /// add, xor, j
+    Op(Vec<Expr>),
+    /// <label>:
+    LabelDef(String),
+    /// j <label>
+    LabelRef(String),
+}
+
+pub struct Location {
+    pub line: usize,
+    pub col: usize,
+    pub start: usize,
+    pub end: usize,
+}
+
+pub fn parse(input: &str) -> Result<Expr, ()> {
+    todo!()
+}

test.s

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+    add r1 r2 r1