feat: allow extern fns

Cargo.lock

@@ -355,6 +355,7 @@ name = "edlang_ir"
 version = "0.0.1-alpha.10"
 dependencies = [
  "edlang_span",
+ "educe",
  "smallvec",
 ]
 
@@ -392,6 +393,18 @@ dependencies = [
 name = "edlang_span"
 version = "0.0.1-alpha.10"
 
+[[package]]
+name = "educe"
+version = "0.5.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e4bd92664bf78c4d3dba9b7cdafce6fa15b13ed3ed16175218196942e99168a8"
+dependencies = [
+ "enum-ordinalize",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "either"
 version = "1.10.0"
@@ -407,6 +420,26 @@ dependencies = [
  "log",
 ]
 
+[[package]]
+name = "enum-ordinalize"
+version = "4.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fea0dcfa4e54eeb516fe454635a95753ddd39acda650ce703031c6973e315dd5"
+dependencies = [
+ "enum-ordinalize-derive",
+]
+
+[[package]]
+name = "enum-ordinalize-derive"
+version = "4.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0d28318a75d4aead5c4db25382e8ef717932d0346600cacae6357eb5941bc5ff"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "equivalent"
 version = "1.0.1"

lib/edlang_ast/src/lib.rs

@@ -140,7 +140,7 @@ pub struct Function {
     pub is_public: bool,
     pub params: Vec<FnParam>,
     pub return_type: Option<Type>,
-    pub body: Block,
+    pub body: Option<Block>,
     pub span: Span,
 }
 

lib/edlang_codegen_llvm/src/codegen.rs

@@ -223,9 +223,7 @@ fn compile_fn_signature(ctx: &ModuleCompileCtx<'_, '_>, fn_id: DefId) {
     let fn_value = ctx.module.add_function(
         &body.get_mangled_name(),
         fn_type,
-        Some(if body.is_extern {
-            inkwell::module::Linkage::AvailableExternally
-        } else if body.is_pub {
+        Some(if body.is_pub || body.is_extern {
             inkwell::module::Linkage::External
         } else {
             inkwell::module::Linkage::Private
@@ -261,7 +259,7 @@ fn compile_fn_signature(ctx: &ModuleCompileCtx<'_, '_>, fn_id: DefId) {
         line as u32 + 1,
         di_type,
         body.is_pub,
-        true,
+        !body.is_extern,
         line as u32 + 1,
         0,
         false,
@@ -271,6 +269,11 @@ fn compile_fn_signature(ctx: &ModuleCompileCtx<'_, '_>, fn_id: DefId) {
 
 fn compile_fn(ctx: &ModuleCompileCtx, fn_id: DefId) -> Result<(), BuilderError> {
     let body = ctx.ctx.program.functions.get(&fn_id).unwrap();
+
+    if body.is_extern {
+        return Ok(());
+    }
+
     trace!("compiling fn body: {}", body.name);
 
     let fn_value = ctx.module.get_function(&body.get_mangled_name()).unwrap();

lib/edlang_ir/Cargo.toml

@@ -15,3 +15,4 @@ repository = "https://github.com/edg-l/edlang"
 [dependencies]
 edlang_span = { version = "0.0.1-alpha.10", path = "../edlang_span" }
 smallvec = "1.13.1"
+educe = "0.5.11"

lib/edlang_ir/src/lib.rs

@@ -6,6 +6,7 @@ use std::{
 };
 
 use edlang_span::Span;
+use educe::Educe;
 use smallvec::SmallVec;
 
 pub mod scalar_int;
@@ -91,6 +92,10 @@ impl Body {
     }
 
     pub fn get_mangled_name(&self) -> String {
+        if self.is_extern {
+            return self.name.clone();
+        }
+
         if self.name == "main" {
             "main".to_string()
         } else {
@@ -221,8 +226,10 @@ pub struct SwitchTarget {
     pub targets: Vec<usize>,
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Debug, Clone, Educe, Eq, PartialOrd, Ord)]
+#[educe(PartialEq)]
 pub struct TypeInfo {
+    #[educe(PartialEq(ignore))]
     pub span: Option<Span>,
     pub kind: TypeKind,
 }

lib/edlang_lowering/src/lib.rs

@@ -170,60 +170,61 @@ fn lower_function(
         .unwrap()
         .clone();
 
-    // store args ret
+    if func.body.is_some() && !func.is_extern {
+        // store args ret
 
-    builder.ret_local = builder.body.locals.len();
-    builder.body.locals.push(Local::new(
-        None,
-        LocalKind::ReturnPointer,
-        ret_ty.clone(),
-        None,
-        false,
-    ));
-
-    for (arg, ty) in func.params.iter().zip(args_ty) {
-        builder
-            .name_to_local
-            .insert(arg.name.name.clone(), builder.body.locals.len());
+        builder.ret_local = builder.body.locals.len();
         builder.body.locals.push(Local::new(
-            Some(arg.name.span),
-            LocalKind::Arg,
-            ty,
-            Some(arg.name.name.clone()),
+            None,
+            LocalKind::ReturnPointer,
+            ret_ty.clone(),
+            None,
             false,
         ));
-    }
 
-    // Get all user defined locals
-    for stmt in &func.body.body {
-        if let ast::Statement::Let(info) = stmt {
-            let ty = lower_type(&builder.ctx, &info.r#type, builder.local_module)?;
+        for (arg, ty) in func.params.iter().zip(args_ty) {
             builder
                 .name_to_local
-                .insert(info.name.name.clone(), builder.body.locals.len());
+                .insert(arg.name.name.clone(), builder.body.locals.len());
             builder.body.locals.push(Local::new(
-                Some(info.name.span),
-                LocalKind::Temp,
+                Some(arg.name.span),
+                LocalKind::Arg,
                 ty,
-                Some(info.name.name.clone()),
-                info.is_mut,
+                Some(arg.name.name.clone()),
+                false,
             ));
         }
-    }
 
-    for stmt in &func.body.body {
-        lower_statement(&mut builder, stmt, &ret_ty)?;
-    }
+        // Get all user defined locals
+        for stmt in &func.body.as_ref().unwrap().body {
+            if let ast::Statement::Let(info) = stmt {
+                let ty = lower_type(&builder.ctx, &info.r#type, builder.local_module)?;
+                builder
+                    .name_to_local
+                    .insert(info.name.name.clone(), builder.body.locals.len());
+                builder.body.locals.push(Local::new(
+                    Some(info.name.span),
+                    LocalKind::Temp,
+                    ty,
+                    Some(info.name.name.clone()),
+                    info.is_mut,
+                ));
+            }
+        }
 
-    if !builder.statements.is_empty() {
-        let statements = std::mem::take(&mut builder.statements);
-        builder.body.blocks.push(BasicBlock {
-            statements: statements.into(),
-            terminator: Terminator::Return,
-            terminator_span: None,
-        });
-    }
+        for stmt in &func.body.as_ref().unwrap().body {
+            lower_statement(&mut builder, stmt, &ret_ty)?;
+        }
 
+        if !builder.statements.is_empty() {
+            let statements = std::mem::take(&mut builder.statements);
+            builder.body.blocks.push(BasicBlock {
+                statements: statements.into(),
+                terminator: Terminator::Return,
+                terminator_span: None,
+            });
+        }
+    }
     let (mut ctx, body) = (builder.ctx, builder.body);
     ctx.unresolved_function_signatures.remove(&body.def_id);
     ctx.body.functions.insert(body.def_id, body);
@@ -478,6 +479,8 @@ fn lower_assign(builder: &mut BodyBuilder, info: &ast::AssignStmt) -> Result<(),
         kind: ty,
     };
 
+    dbg!("here1");
+
     for _ in 0..info.deref_times {
         match &ty.kind {
             TypeKind::Ptr(is_mut, inner) => {
@@ -497,8 +500,12 @@ fn lower_assign(builder: &mut BodyBuilder, info: &ast::AssignStmt) -> Result<(),
         place.projection.push(PlaceElem::Deref);
     }
 
+    dbg!("here2");
+
     let (rvalue, _ty, _span) = lower_expr(builder, &info.value, Some(&ty))?;
 
+    dbg!("here3");
+
     builder.statements.push(Statement {
         span: Some(info.name.first.span),
         kind: StatementKind::Assign(place, rvalue),
@@ -1062,8 +1069,6 @@ fn lower_return(
         let (value, ty, span) = lower_expr(builder, value_expr, Some(return_type))?;
 
         if return_type.kind != ty {
-            dbg!("here");
-            dbg!(value);
             return Err(LoweringError::UnexpectedType {
                 span,
                 found: ty,

lib/edlang_parser/src/grammar.lalrpop

@@ -420,14 +420,24 @@ pub(crate) FnParam: ast::FnParam = {
 }
 
 pub(crate) Function: ast::Function = {
-    <lo:@L> <is_public:"pub"?> <is_extern:"extern"?> "fn" <name:Ident> "(" <params:Comma<FnParam>> ")"
-        <return_type:("->" <Type>)?> <body:Block> <hi:@R> => ast::Function {
+    <lo:@L> <is_public:"pub"?> "extern" "fn" <name:Ident> "(" <params:Comma<FnParam>> ")"
+        <return_type:("->" <Type>)?> ";" <hi:@R> => ast::Function {
         is_public: is_public.is_some(),
-        is_extern: is_extern.is_some(),
+        is_extern: true,
         name,
         params,
         return_type,
-        body,
+        body: None,
+        span: ast::Span::new(lo, hi),
+    },
+    <lo:@L> <is_public:"pub"?> "fn" <name:Ident> "(" <params:Comma<FnParam>> ")"
+        <return_type:("->" <Type>)?> <body:Block> <hi:@R> => ast::Function {
+        is_public: is_public.is_some(),
+        is_extern: false,
+        name,
+        params,
+        return_type,
+        body: Some(body),
         span: ast::Span::new(lo, hi),
     }
 }