WIP implementing simulator

crates/fayalite/src/expr/target.rs

@@ -313,7 +313,7 @@ impl TargetChild {
     }
 }
 
-#[derive(Clone, PartialEq, Eq, Hash)]
+#[derive(Copy, Clone, PartialEq, Eq, Hash)]
 pub enum Target {
     Base(Interned<TargetBase>),
     Child(TargetChild),

crates/fayalite/src/sim.rs

@@ -1,28 +1,32 @@
 //! Fayalite Simulation
 
 use crate::{
-    bundle::{Bundle, BundleType},
+    bundle::{Bundle, BundleField, BundleType},
     enum_::Enum,
-    expr::Expr,
-    int::Bool,
-    intern::{Intern, Interned},
-    module::{
-        Block, Module, ModuleBody, NormalModuleBody, Stmt, StmtConnect, StmtFormal, StmtIf,
-        StmtMatch,
+    expr::{
+        target::{
+            Target, TargetBase, TargetPathArrayElement, TargetPathBundleField, TargetPathElement,
+        },
+        Expr,
+    },
+    int::Bool,
+    intern::{Intern, Interned, Memoize},
+    module::{
+        AnnotatedModuleIO, Block, Instance, Module, ModuleBody, NormalModuleBody, Stmt,
+        StmtConnect, StmtDeclaration, StmtFormal, StmtIf, StmtInstance, StmtMatch,
+    },
+    sim::interpreter::{
+        Insn, Insns, InsnsBuilding, InsnsBuildingDone, SlotDebugData, StatePartLayout, TypeIndex,
+        TypeIndexRange, TypeLayout,
     },
-    sim::interpreter::{Insn, Insns, InsnsBuilding},
     source_location::SourceLocation,
+    ty::CanonicalType,
 };
 use hashbrown::HashMap;
-use std::{cell::RefCell, rc::Rc};
+use std::fmt;
 
 mod interpreter;
 
-#[derive(Debug)]
-struct CompilingModule {
-    compiled_module: Option<CompiledModule>,
-}
-
 #[derive(Debug, PartialEq, Eq, Hash, Clone, Copy)]
 enum CondStack {
     Always,
@@ -44,32 +48,279 @@ enum CondStack {
     },
 }
 
+#[derive(PartialEq, Eq, Hash, Clone, Copy)]
+enum InstantiatedModule {
+    Base(Interned<Module<Bundle>>),
+    Child {
+        parent: Interned<InstantiatedModule>,
+        instance: Interned<Instance<Bundle>>,
+    },
+}
+
+impl InstantiatedModule {
+    fn leaf_module(self) -> Interned<Module<Bundle>> {
+        match self {
+            InstantiatedModule::Base(base) => base,
+            InstantiatedModule::Child { instance, .. } => instance.instantiated(),
+        }
+    }
+    fn write_path(self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            InstantiatedModule::Base(base) => fmt::Debug::fmt(&base.name_id(), f),
+            InstantiatedModule::Child { parent, instance } => {
+                parent.write_path(f)?;
+                write!(f, ".{}", instance.name_id())
+            }
+        }
+    }
+}
+
+impl fmt::Debug for InstantiatedModule {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "InstantiatedModule(")?;
+        self.write_path(f)?;
+        write!(f, ": {})", self.leaf_module().name_id())
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy)]
+struct TargetInInstantiatedModule {
+    instantiated_module: InstantiatedModule,
+    target: Target,
+}
+
+#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy)]
+struct CompiledBundleField {
+    offset: TypeIndex,
+    ty: CompiledTypeLayout,
+}
+
+#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy)]
+enum CompiledTypeLayoutBody {
+    Scalar,
+    Array {
+        /// debug names are ignored, use parent's layout instead
+        element: Interned<CompiledTypeLayout>,
+    },
+    Bundle {
+        /// debug names are ignored, use parent's layout instead
+        fields: Interned<[CompiledBundleField]>,
+    },
+}
+
+#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy)]
+struct CompiledTypeLayout {
+    ty: CanonicalType,
+    layout: TypeLayout<InsnsBuildingDone>,
+    body: CompiledTypeLayoutBody,
+}
+
+impl CompiledTypeLayout {
+    fn with_prefixed_debug_names(self, prefix: &str) -> Self {
+        let Self { ty, layout, body } = self;
+        Self {
+            ty,
+            layout: layout.with_prefixed_debug_names(prefix),
+            body,
+        }
+    }
+    fn get(ty: CanonicalType) -> Self {
+        #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
+        struct MyMemoize;
+        impl Memoize for MyMemoize {
+            type Input = CanonicalType;
+            type InputOwned = CanonicalType;
+            type Output = CompiledTypeLayout;
+
+            fn inner(self, input: &Self::Input) -> Self::Output {
+                match input {
+                    CanonicalType::UInt(_)
+                    | CanonicalType::SInt(_)
+                    | CanonicalType::Bool(_)
+                    | CanonicalType::Enum(_)
+                    | CanonicalType::AsyncReset(_)
+                    | CanonicalType::SyncReset(_)
+                    | CanonicalType::Reset(_)
+                    | CanonicalType::Clock(_) => {
+                        let mut layout = TypeLayout::empty();
+                        let debug_data = SlotDebugData { name: "".intern() };
+                        if input.bit_width() > interpreter::SmallUInt::BITS as usize {
+                            layout.big_slots = StatePartLayout::scalar(debug_data);
+                        } else {
+                            layout.small_slots = StatePartLayout::scalar(debug_data);
+                        };
+                        CompiledTypeLayout {
+                            ty: *input,
+                            layout: layout.into(),
+                            body: CompiledTypeLayoutBody::Scalar,
+                        }
+                    }
+                    CanonicalType::Array(array) => {
+                        let mut layout = TypeLayout::empty();
+                        let element = CompiledTypeLayout::get(array.element()).intern_sized();
+                        for index in 0..array.len() {
+                            layout.allocate(
+                                &element
+                                    .layout
+                                    .with_prefixed_debug_names(&format!("[{index}]")),
+                            );
+                        }
+                        CompiledTypeLayout {
+                            ty: *input,
+                            layout: layout.into(),
+                            body: CompiledTypeLayoutBody::Array { element },
+                        }
+                    }
+                    CanonicalType::Bundle(bundle) => {
+                        let mut layout = TypeLayout::empty();
+                        let fields = bundle
+                            .fields()
+                            .iter()
+                            .map(
+                                |BundleField {
+                                     name,
+                                     flipped: _,
+                                     ty,
+                                 }| {
+                                    let ty = CompiledTypeLayout::get(*ty);
+                                    let offset = layout
+                                        .allocate(
+                                            &ty.layout
+                                                .with_prefixed_debug_names(&format!(".{name}")),
+                                        )
+                                        .start();
+                                    CompiledBundleField { offset, ty }
+                                },
+                            )
+                            .collect();
+                        CompiledTypeLayout {
+                            ty: *input,
+                            layout: layout.into(),
+                            body: CompiledTypeLayoutBody::Bundle { fields },
+                        }
+                    }
+                }
+            }
+        }
+        MyMemoize.get_owned(ty)
+    }
+}
+
+#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy)]
+struct CompiledValue {
+    layout: CompiledTypeLayout,
+    range: TypeIndexRange,
+    write: Option<(CompiledTypeLayout, TypeIndexRange)>,
+}
+
+impl CompiledValue {
+    fn map(
+        self,
+        mut f: impl FnMut(CompiledTypeLayout, TypeIndexRange) -> (CompiledTypeLayout, TypeIndexRange),
+    ) -> Self {
+        let (layout, range) = f(self.layout, self.range);
+        Self {
+            layout,
+            range,
+            write: self.write.map(|(layout, range)| f(layout, range)),
+        }
+    }
+}
+
 #[derive(Debug)]
 pub struct Compiler {
     insns: Insns<InsnsBuilding>,
-    modules: HashMap<Interned<Module<Bundle>>, Rc<RefCell<CompilingModule>>>,
-    module_queue: Vec<Interned<Module<Bundle>>>,
+    base_module: Interned<Module<Bundle>>,
+    modules: HashMap<InstantiatedModule, CompiledModule>,
+    compiled_values: HashMap<TargetInInstantiatedModule, CompiledValue>,
 }
 
 impl Compiler {
-    pub fn new() -> Self {
+    pub fn new(base_module: Interned<Module<Bundle>>) -> Self {
         Self {
             insns: Insns::new(),
+            base_module,
             modules: HashMap::new(),
-            module_queue: Vec::new(),
+            compiled_values: HashMap::new(),
         }
     }
-    pub fn add_module(&mut self, module: Interned<Module<Bundle>>) {
-        self.modules.entry(module).or_insert_with(|| {
-            self.module_queue.push(module);
-            Rc::new(RefCell::new(CompilingModule {
-                compiled_module: None,
-            }))
-        });
+    fn compile_value(&mut self, target: TargetInInstantiatedModule) -> CompiledValue {
+        if let Some(&retval) = self.compiled_values.get(&target) {
+            return retval;
+        }
+        match target.target {
+            Target::Base(base) => {
+                let unprefixed_layout = CompiledTypeLayout::get(base.canonical_ty());
+                let layout = unprefixed_layout.with_prefixed_debug_names(&format!(
+                    "{:?}.{:?}",
+                    target.instantiated_module,
+                    base.target_name()
+                ));
+                let range = self.insns.allocate_variable(&layout.layout);
+                let write = match *base {
+                    TargetBase::ModuleIO(_)
+                    | TargetBase::MemPort(_)
+                    | TargetBase::Wire(_)
+                    | TargetBase::Instance(_) => None,
+                    TargetBase::Reg(_) => {
+                        let write_layout = unprefixed_layout.with_prefixed_debug_names(&format!(
+                            "{:?}.{:?}$next",
+                            target.instantiated_module,
+                            base.target_name()
+                        ));
+                        Some((
+                            write_layout,
+                            self.insns.allocate_variable(&write_layout.layout),
+                        ))
+                    }
+                };
+                CompiledValue {
+                    range,
+                    layout,
+                    write,
+                }
+            }
+            Target::Child(target_child) => {
+                let parent = self.compile_value(TargetInInstantiatedModule {
+                    instantiated_module: target.instantiated_module,
+                    target: *target_child.parent(),
+                });
+                match *target_child.path_element() {
+                    TargetPathElement::BundleField(TargetPathBundleField { name }) => {
+                        parent.map(|layout, range| {
+                            let CompiledTypeLayout {
+                                ty: CanonicalType::Bundle(bundle),
+                                layout: _,
+                                body: CompiledTypeLayoutBody::Bundle { fields },
+                            } = layout
+                            else {
+                                unreachable!();
+                            };
+                            let field_index = bundle.name_indexes()[&name];
+                            (
+                                fields[field_index].ty,
+                                range.slice(TypeIndexRange::new(
+                                    fields[field_index].offset,
+                                    fields[field_index].ty.layout.len(),
+                                )),
+                            )
+                        })
+                    }
+                    TargetPathElement::ArrayElement(TargetPathArrayElement { index }) => parent
+                        .map(|layout, range| {
+                            let CompiledTypeLayoutBody::Array { element } = layout.body else {
+                                unreachable!();
+                            };
+                            (*element, range.index_array(element.layout.len(), index))
+                        }),
+                    TargetPathElement::DynArrayElement(_) => unreachable!(),
+                }
+            }
+        }
     }
     fn compile_block(
         &mut self,
-        module: Interned<Module<Bundle>>,
+        parent_module: Interned<InstantiatedModule>,
         block: Block,
         cond_stack: Interned<CondStack>,
     ) {
@@ -98,7 +349,7 @@ impl Compiler {
                     blocks: [then_block, else_block],
                 }) => {
                     self.compile_block(
-                        module,
+                        parent_module,
                         then_block,
                         CondStack::IfTrue {
                             parent: cond_stack,
@@ -108,7 +359,7 @@ impl Compiler {
                         .intern_sized(),
                     );
                     self.compile_block(
-                        module,
+                        parent_module,
                         else_block,
                         CondStack::IfFalse {
                             parent: cond_stack,
@@ -125,7 +376,7 @@ impl Compiler {
                 }) => {
                     for (variant_index, block) in blocks.into_iter().enumerate() {
                         self.compile_block(
-                            module,
+                            parent_module,
                             block,
                             CondStack::MatchArm {
                                 parent: cond_stack,
@@ -137,67 +388,79 @@ impl Compiler {
                         );
                     }
                 }
-                Stmt::Declaration(stmt_declaration) => todo!(),
+                Stmt::Declaration(declaration) => match declaration {
+                    StmtDeclaration::Wire(wire) => todo!(),
+                    StmtDeclaration::Reg(reg) => todo!(),
+                    StmtDeclaration::Instance(StmtInstance {
+                        annotations,
+                        instance,
+                    }) => {
+                        self.compile_module(
+                            InstantiatedModule::Child {
+                                parent: parent_module,
+                                instance: instance.intern_sized(),
+                            }
+                            .intern_sized(),
+                        );
+                        todo!()
+                    }
+                },
             }
         }
     }
-    fn compile_module(&mut self, module: Interned<Module<Bundle>>) -> CompiledModule {
-        let step_entry_pc = self.insns.next_insn_pc();
-        match module.body() {
+    fn compile_module(&mut self, module: Interned<InstantiatedModule>) -> &CompiledModule {
+        let module_io = module
+            .leaf_module()
+            .module_io()
+            .iter()
+            .map(
+                |&AnnotatedModuleIO {
+                     annotations: _,
+                     module_io,
+                 }| {
+                    self.compile_value(TargetInInstantiatedModule {
+                        instantiated_module: *module,
+                        target: Target::from(module_io),
+                    })
+                },
+            )
+            .collect();
+        match module.leaf_module().body() {
             ModuleBody::Normal(NormalModuleBody { body }) => {
                 self.compile_block(module, body, CondStack::Always.intern_sized())
             }
             ModuleBody::Extern(_extern_module_body) => {
-                todo!("simulating extern module: {}", module.name_id());
+                todo!("simulating extern module: {:?}", module);
             }
         }
-        self.insns.push(Insn::Return, module.source_location());
-        CompiledModule { step_entry_pc }
+        let hashbrown::hash_map::Entry::Vacant(entry) = self.modules.entry(*module) else {
+            unreachable!("compiled same instantiated module twice");
+        };
+        entry.insert(CompiledModule { module_io })
     }
     pub fn run(mut self) -> Compiled {
-        while let Some(module) = self.module_queue.pop() {
-            let compiling_module = self.modules[&module].clone();
-            let mut compiling_module = compiling_module.borrow_mut();
-            let CompilingModule { compiled_module } = &mut *compiling_module;
-            assert!(compiled_module.is_none());
-            *compiled_module = Some(self.compile_module(module));
-        }
+        self.compile_module(InstantiatedModule::Base(self.base_module).intern_sized());
         Compiled {
             insns: Insns::from(self.insns).intern_sized(),
-            modules: self
-                .modules
-                .into_iter()
-                .map(|(module, compiling_module)| {
-                    (
-                        module,
-                        Rc::into_inner(compiling_module)
-                            .expect("only reference is Compiler::modules")
-                            .into_inner()
-                            .compiled_module
-                            .expect("module is compiled by Compiler::run"),
-                    )
-                })
-                .collect(),
+            modules: self.modules,
         }
     }
 }
 
 #[derive(Debug)]
 struct CompiledModule {
-    step_entry_pc: usize,
+    module_io: Interned<[CompiledValue]>,
 }
 
 #[derive(Debug)]
 pub struct Compiled {
-    insns: Interned<Insns>,
-    modules: HashMap<Interned<Module<Bundle>>, CompiledModule>,
+    insns: Interned<Insns<InsnsBuildingDone>>,
+    modules: HashMap<InstantiatedModule, CompiledModule>,
 }
 
 impl Compiled {
     pub fn new<T: BundleType>(module: Module<T>) -> Self {
-        let mut compiler = Compiler::new();
-        compiler.add_module(module.canonical().intern());
-        compiler.run()
+        Compiler::new(module.canonical().intern()).run()
     }
 }