Initial commit

2022-02-18 21:02:17 -06:00
commit 699477c651
11 changed files with 871 additions and 0 deletions
@@ -0,0 +1,120 @@
+use std::convert::TryFrom;
+use std::fmt::{Display, Formatter};
+
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+pub enum Opcode {
+    Nop,
+    Add,
+    Sub,
+    Mul,
+    Div,
+    Mod,
+    Rand,
+    And,
+    Or,
+    Xor,
+    Not,
+    Gt,
+    Lt,
+    Agt,
+    Alt,
+    Lshift,
+    Rshift,
+    Arshift,
+    Pop,
+    Dup,
+    Swap,
+    Pick,
+    Rot,
+    Jmp,
+    Jmpr,
+    Call,
+    Ret,
+    Brz,
+    Brnz,
+    Hlt,
+    Load,
+    Loadw,
+    Store,
+    Storew,
+    Inton,
+    Intoff,
+    Setiv,
+    Sdp,
+    Setsdp,
+    Pushr,
+    Popr,
+    Peekr,
+    Debug,
+}
+
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+pub struct InvalidOpcode(pub u8);
+
+impl Display for InvalidOpcode {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        write!(f, "Invalid opcode {:#02x}", self.0)
+    }
+}
+
+impl std::error::Error for InvalidOpcode {}
+
+impl TryFrom<u8> for Opcode {
+    type Error = InvalidOpcode;
+
+    fn try_from(value: u8) -> Result<Self, Self::Error> {
+        use Opcode::*;
+        Ok(match value {
+            0 => Nop,
+            1 => Add,
+            2 => Sub,
+            3 => Mul,
+            4 => Div,
+            5 => Mod,
+            6 => Rand,
+            7 => And,
+            8 => Or,
+            9 => Xor,
+            10 => Not,
+            11 => Gt,
+            12 => Lt,
+            13 => Agt,
+            14 => Alt,
+            15 => Lshift,
+            16 => Rshift,
+            17 => Arshift,
+            18 => Pop,
+            19 => Dup,
+            20 => Swap,
+            21 => Pick,
+            22 => Rot,
+            23 => Jmp,
+            24 => Jmpr,
+            25 => Call,
+            26 => Ret,
+            27 => Brz,
+            28 => Brnz,
+            29 => Hlt,
+            30 => Load,
+            31 => Loadw,
+            32 => Store,
+            33 => Storew,
+            34 => Inton,
+            35 => Intoff,
+            36 => Setiv,
+            37 => Sdp,
+            38 => Setsdp,
+            39 => Pushr,
+            40 => Popr,
+            41 => Peekr,
+            42 => Debug,
+            other => return Err(InvalidOpcode(other))
+        })
+    }
+}
+
+#[test]
+fn test_decode() {
+    assert_eq!(Opcode::try_from(18), Ok(Opcode::Pop));
+    //assert_eq!(str::fmt("{}", Opcode::try_from(136).unwrap_err()), Err(InvalidOpcode(136)));
+}