WIP.

src/backend/binaryen.rs

@@ -115,6 +115,30 @@ impl Function {
         let s = unsafe { CStr::from_ptr(BinaryenFunctionGetName(self.1)) };
         s.to_str().unwrap()
     }
+
+    pub fn create(
+        module: &mut Module,
+        params: impl Iterator<Item = wasmparser::Type>,
+        results: impl Iterator<Item = wasmparser::Type>,
+        locals: impl Iterator<Item = wasmparser::Type>,
+        body: Expression,
+    ) -> Function {
+        let params = tys_to_binaryen(params);
+        let results = tys_to_binaryen(results);
+        let locals: Vec<BinaryenType> = locals.map(|&ty| Type::from(ty).to_kind()).collect();
+        let ptr = unsafe {
+            BinaryenAddFunc(
+                module.0,
+                /* name = */ std::ptr::null(),
+                params,
+                results,
+                locals.as_ptr(),
+                locals.len() as BinaryenIndex,
+                body.1,
+            )
+        };
+        Function(module.0, ptr)
+    }
 }
 
 impl Export {
@@ -205,6 +229,7 @@ struct TypeIds {
     i64_t: u32,
     f32_t: u32,
     f64_t: u32,
+    v128_t: u32,
 }
 
 impl TypeIds {
@@ -215,6 +240,7 @@ impl TypeIds {
             i64_t: unsafe { BinaryenTypeInt64() },
             f32_t: unsafe { BinaryenTypeFloat32() },
             f64_t: unsafe { BinaryenTypeFloat64() },
+            v128_t: unsafe { BinaryenTypeVec128() },
         }
     }
 }
@@ -230,6 +256,7 @@ pub enum Type {
     I64,
     F32,
     F64,
+    V128,
 }
 
 impl Type {
@@ -250,7 +277,7 @@ impl Type {
         }
     }
 
-    fn to_kind(&self) -> u32 {
+    pub(crate) fn to_kind(&self) -> BinaryenType {
         let tys = &*TYPE_IDS;
         match self {
             &Type::None => tys.none_t,
@@ -258,10 +285,29 @@ impl Type {
             &Type::I64 => tys.i64_t,
             &Type::F32 => tys.f32_t,
             &Type::F64 => tys.f64_t,
+            &Type::V128 => tys.v128_t,
         }
     }
 }
 
+impl From<wasmparser::Type> for Type {
+    fn from(ty: wasmparser::Type) -> Self {
+        match ty {
+            wasmparser::Type::I32 => Type::I32,
+            wasmparser::Type::I64 => Type::I64,
+            wasmparser::Type::F32 => Type::F32,
+            wasmparser::Type::F64 => Type::F64,
+            wasmparser::Type::V128 => Type::V128,
+            _ => unimplemented!(),
+        }
+    }
+}
+
+pub fn tys_to_binaryen(tys: impl Iterator<Item = wasmparser::Type>) -> BinaryenType {
+    let tys: Vec<BinaryenType> = tys.map(|&ty| Type::from(ty).to_kind()).collect();
+    unsafe { BinaryenTypeCreate(tys.as_ptr(), tys.len() as BinaryenIndex) }
+}
+
 fn name_to_string(name: *const c_char) -> Option<String> {
     if name.is_null() {
         None
@@ -517,11 +563,14 @@ extern "C" {
     fn BinaryenUnreachableId() -> u32;
     fn BinaryenPopId() -> u32;
 
-    fn BinaryenTypeNone() -> u32;
+    fn BinaryenTypeNone() -> BinaryenType;
-    fn BinaryenTypeInt32() -> u32;
+    fn BinaryenTypeInt32() -> BinaryenType;
-    fn BinaryenTypeInt64() -> u32;
+    fn BinaryenTypeInt64() -> BinaryenType;
-    fn BinaryenTypeFloat32() -> u32;
+    fn BinaryenTypeFloat32() -> BinaryenType;
-    fn BinaryenTypeFloat64() -> u32;
+    fn BinaryenTypeFloat64() -> BinaryenType;
+    fn BinaryenTypeVec128() -> BinaryenType;
+
+    fn BinaryenTypeCreate(tys: *const BinaryenType, n_tys: BinaryenIndex) -> BinaryenType;
 
     fn BinaryenAddInt32() -> u32;
     fn BinaryenSubInt32() -> u32;
@@ -543,6 +592,16 @@ extern "C" {
         ty: BinaryenType,
     ) -> BinaryenExpression;
 
+    fn BinaryenAddFunc(
+        module: BinaryenModule,
+        name: *const c_char,
+        params: BinaryenType,
+        results: BinaryenType,
+        vars: *const BinaryenType,
+        n_vars: BinaryenIndex,
+        body: BinaryenExpression,
+    ) -> BinaryenFunction;
+
     fn BinaryenUndefined() -> BinaryenType;
 
     fn BinaryenLiteralInt32(x: i32) -> BinaryenLiteral;

src/backend/lower.rs

@@ -0,0 +1,86 @@
+use crate::backend::binaryen;
+use crate::ir::*;
+use fxhash::FxHashMap;
+
+pub(crate) fn generate_body(
+    body: &FunctionBody,
+    into_mod: &mut binaryen::Module,
+) -> binaryen::Expression {
+    // For each block, generate an expr.
+    let mut block_exprs: FxHashMap<BlockId, binaryen::Expression> = FxHashMap::default();
+    let mut ctx = ElabCtx::default();
+    for block in body.blocks() {
+        let exprs = body[block]
+            .insts
+            .iter()
+            .map(|&inst| {
+                let inst = body.resolve_alias(inst);
+                elaborate_value(body, into_mod, &mut ctx, inst)
+            })
+            .collect::<Vec<_>>();
+        block_exprs.insert(block, binaryen::Expression::block(into_mod, &exprs[..]));
+    }
+
+    todo!()
+}
+
+#[derive(Clone, Debug, Default)]
+struct ElabCtx {
+    value_to_expr: FxHashMap<Value, binaryen::Expression>,
+    block_params: FxHashMap<Value, LocalId>,
+    args: FxHashMap<Value, LocalId>,
+}
+
+impl ElabCtx {
+    fn for_func(module: &Module, func: FuncId) -> ElabCtx {
+        let sig = module.func(func).sig();
+        let sig = module.signature(sig);
+        let body = module.func(func).body().unwrap();
+
+        let mut ctx = ElabCtx::default();
+
+        // TODO
+    }
+}
+
+fn elaborate_value(
+    body: &FunctionBody,
+    into_mod: &binaryen::Module,
+    ctx: &mut ElabCtx,
+    value: Value,
+) -> binaryen::Expression {
+    let value = body.resolve_alias(value);
+    if let Some(expr) = ctx.value_to_expr.get(&value) {
+        return *expr;
+    }
+
+    match &body[value] {
+        &ValueDef::BlockParam(block, idx) => {}
+        &ValueDef::Arg(idx) => {}
+        &ValueDef::PickOutput(value, idx) => {}
+        &ValueDef::Operator(op, ref args) => {}
+
+        &ValueDef::Alias(_) => unreachable!(),
+        &ValueDef::Placeholder => unreachable!(),
+    }
+
+    todo!()
+}
+
+pub(crate) fn create_new_func(
+    module: &Module,
+    sig: SignatureId,
+    body: &FunctionBody,
+    into_mod: &mut binaryen::Module,
+    body_expr: binaryen::Expression,
+) {
+    // Create param types.
+    let sig = module.signature(sig);
+    let _func = binaryen::Function::create(
+        into_mod,
+        sig.params.iter().copied(),
+        sig.returns.iter().copied(),
+        body.locals.iter().copied(),
+        body_expr,
+    );
+}

src/ir.rs

@@ -521,6 +521,12 @@ impl<'a> Module<'a> {
 
     pub fn to_wasm_bytes(&self) -> Result<Vec<u8>> {
         let mut binaryen_module = binaryen::Module::read(self.orig_bytes)?;
+        for new_func_idx in self.funcs.len()..binaryen_module.num_funcs() {
+            let sig = self.func(new_func_idx).sig();
+            let body = self.func(new_func_idx).body().unwrap();
+            let binaryen_expr = backend::lower::generate_body(body, &mut binaryen_module);
+            backend::lower::create_new_func(self, sig, body, &mut binaryen_module, binaryen_expr);
+        }
         for &func in &self.dirty_funcs {
             if let Some(body) = self.func(func).body() {
                 let mut binaryen_func = binaryen_module.func(func);