improve function parsing

crates/macro/Cargo.toml

@@ -23,5 +23,6 @@ quote = "1.0.7"
 proc-macro2 = "1.0.18"
 serde = { version = "1.0.110", features = ["derive"] }
 serde_json = "1.0.56"
+uuid = { version = "0.8.1", features = ["v4"] }
 
 fluence-sdk-main = { path = "../main", version = "=0.1.11" }

crates/macro/src/parsed_type.rs

@@ -164,23 +164,24 @@ impl ParsedType {
     }
 }
 
-pub(crate) trait ArgumentsGenerator {
+// TODO: replace String with Ident
+pub(crate) trait MacroPartsGenerator {
     fn generate_arguments(&self) -> Vec<WasmType>;
-}
 
-pub(crate) trait PrologGenerator {
+    fn generate_return_expression(&self) -> proc_macro2::TokenStream;
+
+    fn generate_return_type(&self) -> String;
+
     fn generate_fn_prolog(
         &self,
         generated_arg_id: usize,
         supplied_arg_start_id: usize,
     ) -> proc_macro2::TokenStream;
-}
 
-pub(crate) trait EpilogGenerator {
     fn generate_fn_epilog(&self) -> proc_macro2::TokenStream;
 }
 
-impl ArgumentsGenerator for ParsedType {
+impl MacroPartsGenerator for ParsedType {
     fn generate_arguments(&self) -> Vec<WasmType> {
         // TODO: investigate possible issues in conversion between signed and unsigned types
         match self {
@@ -201,9 +202,37 @@ impl ArgumentsGenerator for ParsedType {
             ParsedType::Record(_) => vec![WasmType::I32, WasmType::I32],
         }
     }
-}
 
-impl PrologGenerator for ParsedType {
+    fn generate_return_expression(&self) -> proc_macro2::TokenStream {
+        match self {
+            ParsedType::Empty => quote! {},
+            ParsedType::Utf8String => quote! {},
+            ParsedType::ByteVector => quote! {},
+            ParsedType::Record(_) => quote! {},
+            _ => quote! {
+                let result =
+            },
+        }
+    }
+
+    fn generate_return_type(&self) -> String {
+        match self {
+            ParsedType::I8 => "-> i32",
+            ParsedType::I16 => "-> i32",
+            ParsedType::I32 => "-> i32",
+            ParsedType::I64 => "-> i64",
+            ParsedType::U8 => "-> i32",
+            ParsedType::U16 => "-> i32",
+            ParsedType::U32 => "-> i32",
+            ParsedType::U64 => "-> i64",
+            ParsedType::F32 => "-> f32",
+            ParsedType::F64 => "-> f64",
+            ParsedType::Boolean => "-> i32",
+            _ => "",
+        }
+        .to_string()
+    }
+
     fn generate_fn_prolog(
         &self,
         generated_ard_id: usize,
@@ -266,44 +295,42 @@ impl PrologGenerator for ParsedType {
             },
         }
     }
-}
 
-impl EpilogGenerator for ParsedType {
     fn generate_fn_epilog(&self) -> proc_macro2::TokenStream {
         match self {
             ParsedType::Empty => quote! {},
             ParsedType::I8 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::I16 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::I32 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::I64 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::U8 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::U16 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::U32 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::U64 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::F32 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::F64 => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::Boolean => quote! {
-                return result;
+                return result as _;
             },
             ParsedType::Utf8String => quote! {
                 fluence::set_result_ptr(result.as_ptr() as _);

crates/macro/src/token_stream_generator.rs

@@ -23,6 +23,8 @@ use crate::fce_ast_types::FCEAst;
 use proc_macro2::TokenStream;
 
 const GENERATED_FUNCS_PREFIX: &str = "__fce_generated_func_";
+const GENERATED_SECTION_NAME: &str = "fce_generated_section";
+const GENERATED_SECTION_PREFIX: &str = "__fce_generated_section";
 
 pub(crate) trait TokenStreamGenerator {
     fn generate_token_stream(self) -> syn::Result<TokenStream>;

crates/macro/src/token_stream_generator/fn_generator.rs

@@ -15,19 +15,50 @@
  */
 
 use crate::fce_ast_types;
-use crate::parsed_type::ArgumentsGenerator;
+use crate::parsed_type::MacroPartsGenerator;
-use crate::parsed_type::EpilogGenerator;
-use crate::parsed_type::PrologGenerator;
 use super::GENERATED_FUNCS_PREFIX;
+use super::GENERATED_SECTION_NAME;
+use super::GENERATED_SECTION_PREFIX;
 use super::TokenStreamGenerator;
 
 use proc_macro2::TokenStream;
 use quote::quote;
+use crate::wasm_type::WasmType;
 
 impl TokenStreamGenerator for fce_ast_types::AstFunctionItem {
     fn generate_token_stream(self) -> syn::Result<TokenStream> {
+        let data = serde_json::to_string(&self).unwrap();
+        let data_size = data.len();
         let func_name = self.name;
-        let prefix = "__fce_generated_func_";
+
+        let prefix = GENERATED_FUNCS_PREFIX;
+        let section_name = GENERATED_SECTION_NAME;
+        let section_prefix = GENERATED_SECTION_PREFIX;
+        let generated_global_name = uuid::Uuid::new_v4().to_string();
+
+        let return_type = self.output_type.generate_return_type();
+        let return_expression = self.output_type.generate_return_expression();
+        let epilog = self.output_type.generate_fn_epilog();
+
+        let mut prolog = TokenStream::new();
+        let mut args: Vec<String> = Vec::with_capacity(self.input_types.len());
+        let mut raw_args: Vec<WasmType> = Vec::with_capacity(self.input_types.len());
+        let mut input_type_id = 0;
+        for input_type in self.input_types {
+            let type_prolog = input_type.generate_fn_prolog(input_type_id, input_type_id);
+            let type_raw_args = input_type.generate_arguments();
+
+            args.extend(
+                type_raw_args
+                    .iter()
+                    .enumerate()
+                    .map(|(id, _)| format!("converted_arg_{}", input_type_id + id)),
+            );
+
+            input_type_id += type_raw_args.len();
+            raw_args.extend(type_raw_args);
+            prolog.extend(type_prolog);
+        }
 
         let embedded_tokens = quote! {
             #[cfg_attr(
@@ -36,10 +67,10 @@ impl TokenStreamGenerator for fce_ast_types::AstFunctionItem {
             )]
             #[doc(hidden)]
             #[allow(clippy::all)]
-            pub extern "C" fn #prefix_#func_name(#(#raw_args)*) #ret_type {
+            pub extern "C" fn #prefix#func_name(#(#raw_args)*) #return_type {
                 #prolog
 
-                #ret_expression #func_name(#(#args)*);
+                #return_expression #func_name(#(#args)*);
 
                 #epilog
             }
@@ -48,7 +79,7 @@ impl TokenStreamGenerator for fce_ast_types::AstFunctionItem {
             #[allow(clippy::all)]
             #[doc(hidden)]
             #[link_section = #section_name]
-            pub static #generated_global_name: [u8; #size] = { #data };
+            pub static #func_name#section_prefix#generated_global_name: [u8; #data_size] = { #data };
         };
 
         Ok(embedded_tokens)

crates/macro/src/wasm_type.rs

@@ -1,5 +1,4 @@
 use proc_macro2::TokenStream;
-use quote::TokenStreamExt;
 
 pub(crate) enum WasmType {
     I32,
@@ -10,6 +9,11 @@ pub(crate) enum WasmType {
 
 impl quote::ToTokens for WasmType {
     fn to_tokens(&self, tokens: &mut TokenStream) {
-        tokens.append(self.clone());
+        match self {
+            WasmType::I32 => "i32".to_tokens(tokens),
+            WasmType::I64 => "i64".to_tokens(tokens),
+            WasmType::F32 => "f32".to_tokens(tokens),
+            WasmType::F64 => "f64".to_tokens(tokens),
+        }
     }
 }