pass records with only pointer without size

crates/wit/src/parsed_type/fn_arg.rs

@@ -31,13 +31,12 @@ impl FnArgGlueCodeGenerator for ParsedType {
             | ParsedType::I32
             | ParsedType::U8
             | ParsedType::U16
-            | ParsedType::U32 => vec![WasmType::I32],
+            | ParsedType::U32
+            | ParsedType::Record(_) => vec![WasmType::I32],
             ParsedType::I64 | ParsedType::U64 => vec![WasmType::I64],
             ParsedType::F32 => vec![WasmType::F32],
             ParsedType::F64 => vec![WasmType::F64],
-            ParsedType::Utf8String | ParsedType::ByteVector | ParsedType::Record(_) => {
-                vec![WasmType::I32, WasmType::I32]
-            }
+            ParsedType::Utf8String | ParsedType::ByteVector => vec![WasmType::I32, WasmType::I32],
         }
     }
 }

crates/wit/src/parsed_type/fn_prolog.rs

@@ -110,7 +110,7 @@ fn generate_type_prolog(
                         GENERATED_RECORD_DESERIALIZER_PREFIX.to_string() + record_name
                     );
                     quote! {
-                        let #generated_arg_id = #deserializer(#ptr, #size);
+                        let #generated_arg_id = #deserializer(#ptr);
                     }
                 }
                 _ => panic!(

crates/wit/src/parsed_type/foreign_mod_arg.rs

@@ -28,9 +28,18 @@ impl ForeignModArgGlueCodeGenerator for ParsedType {
         let arg = crate::new_ident!(format!("arg_{}", arg_start_id));
 
         match self {
-            ParsedType::Utf8String | ParsedType::ByteVector | ParsedType::Record(_) => {
+            ParsedType::Utf8String | ParsedType::ByteVector => {
                 quote! { #arg.as_ptr() as _, #arg.len() as _ }
             }
+            ParsedType::Record(record_name) => {
+                let serializer = crate::new_ident!(
+                    crate::token_stream_generator::GENERATED_RECORD_SERIALIZER_PREFIX.to_string()
+                        + record_name
+                );
+                quote! {
+                    #serializer(#arg)
+                }
+            }
             _ => quote! { arg },
         }
     }

crates/wit/src/parsed_type/foreign_mod_epilog.rs

@@ -64,10 +64,7 @@ impl ForeignModEpilogGlueCodeGenerator for Option<ParsedType> {
                         + record_name
                 );
                 quote! {
-                    #record_deserializer(
-                        fluence::internal::get_result_ptr() as _,
-                        fluence::internal::get_result_size() as _,
-                    );
+                    #record_deserializer(fluence::internal::get_result_ptr() as _)
                 }
             }
             _ => panic!(

crates/wit/src/token_stream_generator/record_generator.rs

@@ -99,9 +99,12 @@ fn generate_deserializer_fn(record: &fce_ast_types::AstRecordItem) -> proc_macro
         return_type,
     } = record.generate_deserializer(&record.name);
 
+    let record_size =
+        crate::utils::get_record_size(record.fields.iter().map(|ast_field| &ast_field.ty));
+
     quote::quote! {
-        unsafe fn #deserializer_fn_name(offset: i32, size: i32) -> #return_type {
-            let raw_record: Vec<u64> = Vec::from_raw_parts(offset as _, size as _, size as _);
+        unsafe fn #deserializer_fn_name(offset: i32) -> #return_type {
+            let raw_record: Vec<u64> = Vec::from_raw_parts(offset as _, #record_size, #record_size);
 
             #deserializer
 

crates/wit/src/token_stream_generator/record_generator/record_deserializer.rs

@@ -118,13 +118,11 @@ impl RecordDeserializerGlueCodeGenerator for fce_ast_types::AstRecordItem {
                 }
                 ParsedType::Record(record_name) => {
                     let ptr_id = value_id;
-                    let size_id = value_id + 1;
-                    value_id += 1;
                     let record_deserializer =
                         new_ident!(GENERATED_RECORD_DESERIALIZER_PREFIX.to_string() + record_name);
 
                     quote! {
-                        let #field = #record_deserializer(raw_record[#ptr_id] as _, raw_record[#size_id] as _);
+                        let #field = #record_deserializer(raw_record[#ptr_id] as _);
                     }
                 }
             };

crates/wit/src/utils.rs

@@ -39,3 +39,22 @@ macro_rules! prepare_global_data {
             + &$name.replace(".", "_");
     };
 }
+
+pub fn get_record_size<'a>(
+    fields: impl Iterator<Item = &'a crate::parsed_type::ParsedType>,
+) -> usize {
+    use crate::parsed_type::ParsedType;
+
+    let mut size = 0;
+
+    for field in fields {
+        let params_count = match field {
+            ParsedType::ByteVector | ParsedType::Utf8String => 2,
+            _ => 1,
+        };
+
+        size += std::mem::size_of::<u64>() * params_count;
+    }
+
+    size
+}