From 6d31a9ea6f4373d91af0cc86394b5ee7d3bd779e Mon Sep 17 00:00:00 2001
From: Edgar Luque <git@edgarluque.com>
Date: Sat, 17 Feb 2024 12:37:28 +0100
Subject: [PATCH] refs

---
 lib/edlang_ast/src/lib.rs              |  7 +++++++
 lib/edlang_codegen_llvm/src/codegen.rs | 14 +++++++++++++-
 lib/edlang_ir/src/lib.rs               |  2 ++
 lib/edlang_lowering/src/lib.rs         | 16 +++++++++++++++-
 lib/edlang_parser/src/grammar.lalrpop  | 11 +++++++++--
 5 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/lib/edlang_ast/src/lib.rs b/lib/edlang_ast/src/lib.rs
index ca1b512c6a..ba9a6fd23c 100644
--- a/lib/edlang_ast/src/lib.rs
+++ b/lib/edlang_ast/src/lib.rs
@@ -62,6 +62,7 @@ pub struct Ident {
 pub struct Type {
     pub name: Ident,
     pub generics: Vec<Type>,
+    pub is_ref: Option<RefType>,
     pub span: Span,
 }
 
@@ -72,6 +73,12 @@ pub struct FnParam {
     pub span: Span,
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum RefType {
+    Not,
+    Mut,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Block {
     pub body: Vec<Statement>,
diff --git a/lib/edlang_codegen_llvm/src/codegen.rs b/lib/edlang_codegen_llvm/src/codegen.rs
index c01dedf888..9f24a7ed73 100644
--- a/lib/edlang_codegen_llvm/src/codegen.rs
+++ b/lib/edlang_codegen_llvm/src/codegen.rs
@@ -18,7 +18,7 @@ use inkwell::{
     AddressSpace,
 };
 use ir::{LocalKind, ModuleBody, ProgramBody, TypeInfo, ValueTree};
-use llvm_sys::debuginfo::LLVMDIFlagPublic;
+use llvm_sys::debuginfo::{LLVMDIFlagLValueReference, LLVMDIFlagPublic};
 use tracing::{info, trace};
 
 #[derive(Debug, Clone, Copy)]
@@ -1083,6 +1083,12 @@ fn compile_basic_type<'ctx>(
             .ptr_sized_int_type(&ctx.target_data, None)
             .ptr_type(AddressSpace::default())
             .as_basic_type_enum(),
+        ir::TypeKind::Ref(_, _) => ctx
+            .ctx
+            .context
+            .ptr_sized_int_type(&ctx.target_data, None)
+            .ptr_type(AddressSpace::default())
+            .as_basic_type_enum(),
     }
 }
 
@@ -1093,6 +1099,8 @@ fn compile_debug_type<'ctx>(ctx: &ModuleCompileCtx<'ctx, '_>, ty: &ir::TypeInfo)
     // 5 = signed
     // 11 = numeric string
     // https://dwarfstd.org/doc/DWARF5.pdf#section.7.8
+
+    // https://github.com/GaloisInc/dwarf-tools/blob/master/src/DWARF/DW/TAG.hs
     match &ty.kind {
         ir::TypeKind::Unit => todo!(),
         ir::TypeKind::Bool => ctx
@@ -1194,5 +1202,9 @@ fn compile_debug_type<'ctx>(ctx: &ModuleCompileCtx<'ctx, '_>, ty: &ir::TypeInfo)
                 AddressSpace::default(),
             )
             .as_type(),
+        ir::TypeKind::Ref(_, inner) => ctx
+            .di_builder
+            .create_reference_type(compile_debug_type(ctx, inner), 0x10)
+            .as_type(),
     }
 }
diff --git a/lib/edlang_ir/src/lib.rs b/lib/edlang_ir/src/lib.rs
index 91fe5af2de..1bc3cfb060 100644
--- a/lib/edlang_ir/src/lib.rs
+++ b/lib/edlang_ir/src/lib.rs
@@ -204,6 +204,7 @@ pub enum TypeKind {
     Float(FloatTy),
     FnDef(DefId, Vec<TypeInfo>), // The vec are generic types, not arg types
     Ptr(Box<TypeInfo>),
+    Ref(bool, Box<TypeInfo>),
 }
 
 impl TypeKind {
@@ -235,6 +236,7 @@ impl TypeKind {
             TypeKind::Unit => unreachable!(),
             TypeKind::FnDef(_, _) => unreachable!(),
             TypeKind::Ptr(_pointee) => todo!(),
+            TypeKind::Ref(_, inner) => inner.kind.get_falsy_value(),
         }
     }
 }
diff --git a/lib/edlang_lowering/src/lib.rs b/lib/edlang_lowering/src/lib.rs
index 1d3be6ba36..cbf91f6a37 100644
--- a/lib/edlang_lowering/src/lib.rs
+++ b/lib/edlang_lowering/src/lib.rs
@@ -802,7 +802,7 @@ fn lower_path(builder: &mut BodyBuilder, info: &ast::PathExpr) -> (ir::Place, Ty
 
 #[allow(clippy::only_used_in_recursion)]
 pub fn lower_type(ctx: &BuildCtx, t: &ast::Type) -> ir::TypeInfo {
-    match t.name.name.as_str() {
+    let inner_ty = match t.name.name.as_str() {
         "()" => ir::TypeInfo {
             span: Some(t.span),
             kind: ir::TypeKind::Unit,
@@ -860,5 +860,19 @@ pub fn lower_type(ctx: &BuildCtx, t: &ast::Type) -> ir::TypeInfo {
             kind: ir::TypeKind::Ptr(Box::new(lower_type(ctx, t.generics.first().unwrap()))),
         },
         x => todo!("{:?}", x),
+    };
+
+    match t.is_ref {
+        Some(x) => ir::TypeInfo {
+            span: Some(t.span),
+            kind: TypeKind::Ref(
+                match x {
+                    ast::RefType::Not => false,
+                    ast::RefType::Mut => true,
+                },
+                Box::new(inner_ty),
+            ),
+        },
+        None => inner_ty,
     }
 }
diff --git a/lib/edlang_parser/src/grammar.lalrpop b/lib/edlang_parser/src/grammar.lalrpop
index dcc75feed5..429a84764b 100644
--- a/lib/edlang_parser/src/grammar.lalrpop
+++ b/lib/edlang_parser/src/grammar.lalrpop
@@ -141,14 +141,16 @@ pub(crate) Ident: ast::Ident = {
 }
 
 pub(crate) Type: ast::Type = {
-    <lo:@L> <name:Ident> <hi:@R> => ast::Type {
+    <lo:@L> <is_ref:RefType?> <name:Ident> <hi:@R> => ast::Type {
         name,
         generics: vec![],
+        is_ref,
         span: ast::Span::new(lo, hi),
     },
-    <lo:@L> <name:Ident> "<" <generics:Comma<Type>> ">" <hi:@R> => ast::Type {
+    <lo:@L> <is_ref:RefType?> <name:Ident> "<" <generics:Comma<Type>> ">" <hi:@R> => ast::Type {
         name,
         generics,
+        is_ref,
         span: ast::Span::new(lo, hi),
     },
 }
@@ -346,6 +348,11 @@ pub(crate) ValueExpr: ast::ValueExpr = {
   <PathExpr> => ast::ValueExpr::Path(<>),
 }
 
+pub(crate) RefType: ast::RefType = {
+    "&" => ast::RefType::Not,
+    "&" "mut" => ast::RefType::Mut,
+}
+
 pub(crate) FnParam: ast::FnParam = {
     <lo:@L> <name:Ident> ":" <arg_type:Type> <hi:@R> => ast::FnParam {
         name,