Merge pull request #4 from slothlang/vm-basics

Basic VM

1 files changed, 54 insertions, 41 deletions

diff --git a/crates/sloth_bytecode/src/lib.rs b/crates/sloth_bytecode/src/lib.rs
index 3593f3c..2319330 100644
--- a/crates/sloth_bytecode/src/lib.rs
+++ b/crates/sloth_bytecode/src/lib.rs
@@ -7,56 +7,69 @@
     unused_lifetimes
 )]
 
-use sloth_bytecode_macros::instructions;
-
 pub enum Error {
     UnknownOpcode(u8),
     InvalidArguments,
     Eof,
 }
 
-instructions! {
-    Instructions;
+macro_rules! opcodes {
+    ( $( $code:literal $name:ident $docs:literal ),* ) => {
+        #[repr(u8)]
+        #[derive(Debug, Clone, Copy, Eq, PartialEq)]
+        pub enum Opcode {
+            $(
+                #[doc = $docs]
+                $name = $code
+            ),*
+        }
 
-    0x00 Constant   [u64]   "Push a constant value onto the stack",
-    0x01 Load       [u64]   "Load a value from a variable",
-    0x02 Push       [u64]   "Push a value to a variable",
+        impl Opcode {
+            pub fn into_u8(self) -> u8 {
+                self as u8
+            }
 
-    0x10 Dup        []      "Duplicate a value on the stack",
-    0x11 Pop        []      "Pop a value from the stack",
+            pub fn from_u8(value: u8) -> Opcode {
+                match value {
+                    $( $code => Self:: $name , )*
+                    _ => panic!("Invalid opcode"),
+                }
+            }
+        }
+    };
+}
 
-    0x20 Add        []      "Add the last 2 values on the stack",
-    0x21 Sub        []      "Subtract the last 2 values on the stack",
-    0x22 Mul        []      "Multiply the last 2 values on the stack",
-    0x23 Div        []      "Divide the last 2 values on the stack",
-    0x24 Mod        []      "Modulo the last 2 values on the stack",
+opcodes! {
+    0x00 Constant   "Push a constant value onto the stack",
+    0x01 Load       "Load a value from a variable",
+    0x02 Push       "Push a value to a variable",
 
-    0xF0 Print      []      "[DEBUG] Pop value from stack and print it"
-}
+    0x10 Dup        "Duplicate a value on the stack",
+    0x11 Pop        "Pop a value from the stack",
+
+    0x12 GetGlobal  "Get a global value",
+    0x13 SetGlobal  "Set a global value",
+    0x14 GetLocal   "Get a local value",
+    0x15 SetLocal   "Set a local value",
+
+    0x20 Add        "Add the last 2 values on the stack",
+    0x21 Sub        "Subtract the last 2 values on the stack",
+    0x22 Mul        "Multiply the last 2 values on the stack",
+    0x23 Div        "Divide the last 2 values on the stack",
+    0x24 Mod        "Modulo the last 2 values on the stack",
+
+    0x30 Eq         "Check if the last 2 values on the stack are equal",
+    0x31 Ne         "Check if the last 2 values on the stack are not equal",
+
+    0x40 Jump       "Jump to a specific point in the program",
+    0x41 JumpIf     "Jump to a specific point in the program if true is on the stack",
+
+    0x50 Call       "Call function on stack",
+    0x51 CallNative "Call native function",
+    0x52 Return     "Return from function on stack",
+
+    0xE0 Halt       "Halt the program",
 
-#[cfg(test)]
-mod tests {
-    use crate::Instructions;
-
-    #[test]
-    #[rustfmt::skip]
-    fn decompile_basic_instructions() {
-        let code = [
-            // Load constant 0
-            0x00, 0, 0, 0, 0, 0, 0, 0, 0, 
-            // Pop, Dup, Add, Sub, Mul, Div, Mod
-            0x10, 0x11, 0x20, 0x21, 0x22, 0x23, 0x24,
-        ];
-
-        let mut offset = 0;
-
-        assert_eq!(Instructions::disassemble(&code, &mut offset), Instructions::Constant(0));
-        assert_eq!(Instructions::disassemble(&code, &mut offset), Instructions::Dup);
-        assert_eq!(Instructions::disassemble(&code, &mut offset), Instructions::Pop);
-        assert_eq!(Instructions::disassemble(&code, &mut offset), Instructions::Add);
-        assert_eq!(Instructions::disassemble(&code, &mut offset), Instructions::Sub);
-        assert_eq!(Instructions::disassemble(&code, &mut offset), Instructions::Mul);
-        assert_eq!(Instructions::disassemble(&code, &mut offset), Instructions::Div);
-        assert_eq!(Instructions::disassemble(&code, &mut offset), Instructions::Mod);
-    }
+    0xF0 VMReturn   "[DEBUG] Pop value from stack and return it fromthe program",
+    0xF1 VMPrint    "[DEBUG] Print value to console"
 }