feat: error handling

evaluator/nixjit_jit/src/helpers.rs

@@ -12,6 +12,7 @@ use std::ptr::NonNull;
 use hashbrown::HashMap;
 
 use nixjit_eval::{AttrSet, EvalContext, List, Value};
+use nixjit_ir::ArgIdx;
 
 use super::JITContext;
 
@@ -34,7 +35,7 @@ pub extern "C" fn helper_call<Ctx: JITContext>(
 /// Helper function to look up a value in the evaluation stack.
 ///
 /// This function is called from JIT-compiled code to access values in the evaluation stack.
-pub extern "C" fn helper_lookup_stack<Ctx: JITContext>(
+pub extern "C" fn helper_lookup_stack<Ctx: JITContext + EvalContext>(
     ctx: &Ctx,
     offset: usize,
     ret: &mut MaybeUninit<Value>,
@@ -45,12 +46,12 @@ pub extern "C" fn helper_lookup_stack<Ctx: JITContext>(
 /// Helper function to look up a function argument.
 ///
 /// This function is called from JIT-compiled code to access function arguments.
-pub extern "C" fn helper_lookup_arg<Ctx: JITContext>(
+pub extern "C" fn helper_lookup_arg<Ctx: EvalContext>(
     ctx: &Ctx,
-    offset: usize,
+    idx: ArgIdx,
     ret: &mut MaybeUninit<Value>,
 ) {
-    ret.write(JITContext::lookup_arg(ctx, offset).clone());
+    ret.write(ctx.lookup_arg(idx).clone());
 }
 
 /// Helper function to look up a variable by name.
@@ -87,7 +88,7 @@ pub extern "C" fn helper_select<Ctx: JITContext>(
     let path = core::ptr::slice_from_raw_parts_mut(path_ptr, path_len);
     let path = unsafe { Box::from_raw(path) };
     val.select(path.into_iter().map(|mut val| {
-        val.coerce_to_string();
+        val.coerce_to_string().unwrap();
         Ok(val.unwrap_string())
     }))
     .unwrap();
@@ -107,7 +108,7 @@ pub extern "C" fn helper_select_with_default<Ctx: JITContext>(
     let path = unsafe { Box::from_raw(path) };
     val.select_with_default(
         path.into_iter().map(|mut val| {
-            val.coerce_to_string();
+            val.coerce_to_string().unwrap();
             Ok(val.unwrap_string())
         }),
         unsafe { default.read() },
@@ -119,7 +120,7 @@ pub extern "C" fn helper_select_with_default<Ctx: JITContext>(
 ///
 /// This function is called from JIT-compiled code to perform equality comparisons.
 pub extern "C" fn helper_eq<Ctx: JITContext>(lhs: &mut Value, rhs: &Value) {
-    lhs.eq(rhs);
+    lhs.eq(unsafe { core::ptr::read(rhs) });
 }
 
 /// Helper function to create a string value.

evaluator/nixjit_jit/src/lib.rs

@@ -32,13 +32,8 @@ use helpers::*;
 /// A trait that provides the execution context for JIT-compiled code.
 ///
 /// This trait extends `EvalContext` with additional methods needed
-/// for JIT compilation, such as stack and argument lookups, and
-/// managing `with` expression scopes.
+/// for JIT compilation, such as managing `with` expression scopes directly.
 pub trait JITContext: EvalContext {
-    /// Looks up a value in the evaluation stack by offset.
-    fn lookup_stack(&self, offset: usize) -> &Value;
-    /// Looks up a function argument by offset.
-    fn lookup_arg(&self, offset: usize) -> &Value;
     /// Enters a `with` expression scope with the given namespace.
     fn enter_with(&mut self, namespace: Rc<HashMap<String, Value>>);
     /// Exits the current `with` expression scope.