feat(runtime): add marshalling of value structs

crates/mun/src/main.rs

@@ -1,6 +1,8 @@
 #[macro_use]
 extern crate failure;
 
+use std::cell::RefCell;
+use std::rc::Rc;
 use std::time::Duration;
 
 use clap::{App, AppSettings, Arg, ArgMatches, SubCommand};
@@ -84,10 +86,11 @@ fn build(matches: &ArgMatches) -> Result<(), failure::Error> {
 
 /// Starts the runtime with the specified library and invokes function `entry`.
 fn start(matches: &ArgMatches) -> Result<(), failure::Error> {
-    let mut runtime = runtime(matches)?;
+    let runtime = Rc::new(RefCell::new(runtime(matches)?));
 
+    let borrowed = runtime.borrow();
     let entry_point = matches.value_of("entry").unwrap_or("main");
-    let fn_info = runtime.get_function_info(entry_point).ok_or_else(|| {
+    let fn_info = borrowed.get_function_info(entry_point).ok_or_else(|| {
         std::io::Error::new(
             std::io::ErrorKind::InvalidInput,
             format!("Failed to obtain entry point '{}'", entry_point),

crates/mun_abi/src/autogen.rs

@@ -3,7 +3,7 @@
 /* automatically generated by rust-bindgen */
 
 #![allow(non_snake_case, non_camel_case_types, non_upper_case_globals)]
-use crate::{Privacy, TypeGroup};
+use crate::{Privacy, StructMemoryKind, TypeGroup};
 
 #[doc = " Represents a globally unique identifier (GUID)."]
 #[doc = ""]
@@ -236,6 +236,8 @@ pub struct StructInfo {
     pub field_sizes: *const u16,
     #[doc = " Number of fields"]
     pub num_fields: u16,
+    #[doc = " Struct memory kind"]
+    pub memory_kind: StructMemoryKind,
 }
 #[test]
 fn bindgen_test_layout_StructInfo() {
@@ -309,6 +311,16 @@ fn bindgen_test_layout_StructInfo() {
             stringify!(num_fields)
         )
     );
+    assert_eq!(
+        unsafe { &(*(::std::ptr::null::<StructInfo>())).memory_kind as *const _ as usize },
+        42usize,
+        concat!(
+            "Offset of field: ",
+            stringify!(StructInfo),
+            "::",
+            stringify!(memory_kind)
+        )
+    );
 }
 #[doc = " Represents a module declaration."]
 #[doc = ""]

crates/mun_abi/src/autogen_impl.rs

@@ -468,6 +468,7 @@ mod tests {
         field_types: &[&TypeInfo],
         field_offsets: &[u16],
         field_sizes: &[u16],
+        memory_kind: StructMemoryKind,
     ) -> StructInfo {
         assert!(field_names.len() == field_types.len());
         assert!(field_types.len() == field_offsets.len());
@@ -480,6 +481,7 @@ mod tests {
             field_offsets: field_offsets.as_ptr(),
             field_sizes: field_sizes.as_ptr(),
             num_fields: field_names.len() as u16,
+            memory_kind,
         }
     }
 
@@ -488,7 +490,7 @@ mod tests {
     #[test]
     fn test_struct_info_name() {
         let struct_name = CString::new(FAKE_STRUCT_NAME).expect("Invalid fake struct name.");
-        let struct_info = fake_struct_info(&struct_name, &[], &[], &[], &[]);
+        let struct_info = fake_struct_info(&struct_name, &[], &[], &[], &[], Default::default());
 
         assert_eq!(struct_info.name(), FAKE_STRUCT_NAME);
     }
@@ -506,6 +508,7 @@ mod tests {
             field_types,
             field_offsets,
             field_sizes,
+            Default::default(),
         );
 
         assert_eq!(struct_info.field_names().count(), 0);
@@ -531,6 +534,7 @@ mod tests {
             field_types,
             field_offsets,
             field_sizes,
+            Default::default(),
         );
 
         for (lhs, rhs) in struct_info.field_names().zip([FAKE_FIELD_NAME].iter()) {
@@ -555,6 +559,26 @@ mod tests {
         }
     }
 
+    #[test]
+    fn test_struct_info_memory_kind_gc() {
+        let struct_name = CString::new(FAKE_STRUCT_NAME).expect("Invalid fake struct name.");
+        let struct_memory_kind = StructMemoryKind::GC;
+        let struct_info =
+            fake_struct_info(&struct_name, &[], &[], &[], &[], struct_memory_kind.clone());
+
+        assert_eq!(struct_info.memory_kind, struct_memory_kind);
+    }
+
+    #[test]
+    fn test_struct_info_memory_kind_value() {
+        let struct_name = CString::new(FAKE_STRUCT_NAME).expect("Invalid fake struct name.");
+        let struct_memory_kind = StructMemoryKind::Value;
+        let struct_info =
+            fake_struct_info(&struct_name, &[], &[], &[], &[], struct_memory_kind.clone());
+
+        assert_eq!(struct_info.memory_kind, struct_memory_kind);
+    }
+
     const FAKE_MODULE_PATH: &str = "path::to::module";
 
     #[test]
@@ -592,7 +616,7 @@ mod tests {
         let functions = &[fn_info];
 
         let struct_name = CString::new(FAKE_STRUCT_NAME).expect("Invalid fake struct name");
-        let struct_info = fake_struct_info(&struct_name, &[], &[], &[], &[]);
+        let struct_info = fake_struct_info(&struct_name, &[], &[], &[], &[], Default::default());
         let struct_type_info = fake_struct_type_info(&struct_name, struct_info);
         let types = &[unsafe { mem::transmute(&struct_type_info) }];
 

crates/mun_abi/src/lib.rs

@@ -15,7 +15,37 @@ pub use autogen::*;
 /// The *prelude* contains imports that are used almost every time.
 pub mod prelude {
     pub use crate::autogen::*;
-    pub use crate::{Privacy, TypeGroup};
+    pub use crate::{Privacy, StructMemoryKind, TypeGroup};
+}
+
+/// Represents the kind of memory management a struct uses.
+#[repr(u8)]
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum StructMemoryKind {
+    /// A garbage collected struct is allocated on the heap and uses reference semantics when passed
+    /// around.
+    GC,
+
+    /// A value struct is allocated on the stack and uses value semantics when passed around.
+    ///
+    /// NOTE: When a value struct is used in an external API, a wrapper is created that _pins_ the
+    /// value on the heap. The heap-allocated value needs to be *manually deallocated*!
+    Value,
+}
+
+impl Default for StructMemoryKind {
+    fn default() -> Self {
+        StructMemoryKind::GC
+    }
+}
+
+impl From<StructMemoryKind> for u64 {
+    fn from(kind: StructMemoryKind) -> Self {
+        match kind {
+            StructMemoryKind::GC => 0,
+            StructMemoryKind::Value => 1,
+        }
+    }
 }
 
 /// Represents the privacy level of modules, functions, or variables.

crates/mun_codegen/src/code_gen/abi_types.rs

@@ -78,6 +78,7 @@ pub(super) fn gen_abi_types(context: ContextRef) -> AbiTypes {
             context.i16_type().ptr_type(AddressSpace::Const).into(), // field_offsets
             context.i16_type().ptr_type(AddressSpace::Const).into(), // field_sizes
             context.i16_type().into(),                               // num_fields
+            context.i8_type().into(),                                // memory_kind
         ],
         false,
     );

crates/mun_codegen/src/code_gen/symbols.rs

@@ -5,7 +5,7 @@ use crate::ir::{
 };
 use crate::type_info::{TypeGroup, TypeInfo};
 use crate::values::{BasicValue, GlobalValue};
-use crate::IrDatabase;
+use crate::{CodeGenParams, IrDatabase};
 use hir::Ty;
 use inkwell::{
     attributes::Attribute,
@@ -262,7 +262,6 @@ fn gen_function_info_array<'a, D: IrDatabase>(
     functions: impl Iterator<Item = (&'a hir::Function, &'a FunctionValue)>,
 ) -> GlobalArrayValue {
     let function_infos: Vec<StructValue> = functions
-        .filter(|(f, _)| f.visibility(db) == hir::Visibility::Public)
         .map(|(f, value)| {
             // Get the function from the cloned module and modify the linkage of the function.
             let value = module
@@ -321,9 +320,9 @@ fn gen_struct_info<D: IrDatabase>(
         (0..fields.len()).map(|idx| target_data.offset_of_element(&t, idx as u32).unwrap());
     let (field_offsets, _) = gen_u16_array(module, field_offsets);
 
-    let field_sizes = fields
-        .iter()
-        .map(|field| target_data.get_store_size(&db.type_ir(field.ty(db))));
+    let field_sizes = fields.iter().map(|field| {
+        target_data.get_store_size(&db.type_ir(field.ty(db), CodeGenParams { is_extern: false }))
+    });
     let (field_sizes, _) = gen_u16_array(module, field_sizes);
 
     types.struct_info_type.const_named_struct(&[
@@ -337,6 +336,11 @@ fn gen_struct_info<D: IrDatabase>(
             .i16_type()
             .const_int(num_fields as u64, false)
             .into(),
+        module
+            .get_context()
+            .i8_type()
+            .const_int(s.data(db).memory_kind.clone().into(), false)
+            .into(),
     ])
 }
 

crates/mun_codegen/src/db.rs

@@ -1,6 +1,6 @@
 #![allow(clippy::type_repetition_in_bounds)]
 
-use crate::{ir::module::ModuleIR, type_info::TypeInfo, Context};
+use crate::{ir::module::ModuleIR, type_info::TypeInfo, CodeGenParams, Context};
 use inkwell::types::StructType;
 use inkwell::{types::AnyTypeEnum, OptimizationLevel};
 use mun_target::spec::Target;
@@ -22,9 +22,9 @@ pub trait IrDatabase: hir::HirDatabase {
     #[salsa::input]
     fn target(&self) -> Target;
 
-    /// Given a type, return the corresponding IR type.
+    /// Given a type and code generation parameters, return the corresponding IR type.
     #[salsa::invoke(crate::ir::ty::ir_query)]
-    fn type_ir(&self, ty: hir::Ty) -> AnyTypeEnum;
+    fn type_ir(&self, ty: hir::Ty, params: CodeGenParams) -> AnyTypeEnum;
 
     /// Given a struct, return the corresponding IR type.
     #[salsa::invoke(crate::ir::ty::struct_ty_query)]

crates/mun_codegen/src/intrinsics.rs

@@ -1,4 +1,5 @@
 use crate::ir::dispatch_table::FunctionPrototype;
+use crate::type_info::TypeInfo;
 use inkwell::context::Context;
 use inkwell::types::FunctionType;
 
@@ -18,4 +19,6 @@ pub trait Intrinsic: Sync {
 intrinsics! {
     /// Allocates memory from the runtime to use in code.
     pub fn malloc(size: u64, alignment: u64) -> *mut u8;
+    /// Allocates memory for and clones the specified type located at `src` into it.
+    pub fn clone(src: *const u8, ty: *const TypeInfo) -> *mut u8;
 }

crates/mun_codegen/src/intrinsics/macros.rs

@@ -1,5 +1,5 @@
 macro_rules! intrinsics{
-    ($($(#[$attr:meta])* pub fn $name:ident($($arg_name:ident:$arg:ty),*) -> $ret:ty;);*) => {
+    ($($(#[$attr:meta])* pub fn $name:ident($($arg_name:ident:$arg:ty),+) -> $ret:ty;)+) => {
         $(
             paste::item! {
                 pub struct [<Intrinsic $name>];

crates/mun_codegen/src/ir.rs

@@ -1,3 +1,4 @@
+use crate::type_info::TypeInfo;
 use inkwell::context::Context;
 use inkwell::types::{
     AnyType, AnyTypeEnum, BasicType, BasicTypeEnum, FunctionType, IntType, PointerType,
@@ -183,6 +184,13 @@ impl<S: BasicType, T: IsIrType<Type = S>> IsPointerType for *const T {
     }
 }
 
+// HACK: Manually add `*const TypeInfo`
+impl IsPointerType for *const TypeInfo {
+    fn ir_type(context: &Context) -> PointerType {
+        context.i8_type().ptr_type(AddressSpace::Const)
+    }
+}
+
 impl<S: BasicType, T: IsIrType<Type = S>> IsPointerType for *mut T {
     fn ir_type(context: &Context) -> PointerType {
         T::ir_type(context).ptr_type(AddressSpace::Generic)

crates/mun_codegen/src/ir/adt.rs

@@ -1,6 +1,6 @@
 //use crate::ir::module::Types;
 use crate::ir::try_convert_any_to_basic;
-use crate::IrDatabase;
+use crate::{CodeGenParams, IrDatabase};
 use inkwell::types::{BasicTypeEnum, StructType};
 
 pub(super) fn gen_struct_decl(db: &impl IrDatabase, s: hir::Struct) -> StructType {
@@ -11,7 +11,7 @@ pub(super) fn gen_struct_decl(db: &impl IrDatabase, s: hir::Struct) -> StructTyp
             .iter()
             .map(|field| {
                 let field_type = field.ty(db);
-                try_convert_any_to_basic(db.type_ir(field_type))
+                try_convert_any_to_basic(db.type_ir(field_type, CodeGenParams { is_extern: false }))
                     .expect("could not convert field type")
             })
             .collect();