Re: [PATCH olang 4/5] codegen: calculate the variable offset based on symbol type

[Johnny Richard <johnny@johnnyrichard.com>]

On Sat, Sep 21, 2024 at 08:25:00AM GMT, Carlos Maniero wrote:
> This is just an initial structure although it still only supporting u32.
> 
> Signed-off-by: Carlos Maniero <carlos@maniero.me>
> ---
>  src/codegen_linux_x86_64.c | 26 ++++++++++++++++++++++----
>  1 file changed, 22 insertions(+), 4 deletions(-)
> 
> diff --git a/src/codegen_linux_x86_64.c b/src/codegen_linux_x86_64.c
> index 1fa6c58..415c81b 100644
> --- a/src/codegen_linux_x86_64.c
> +++ b/src/codegen_linux_x86_64.c
> @@ -35,6 +35,9 @@ codegen_linux_x86_64_emit_start_entrypoint(codegen_x86_64_t *codegen);
>  static void
>  codegen_linux_x86_64_emit_function(codegen_x86_64_t *codegen, ast_fn_definition_t *fn);
>  
> +static size_t
> +type_to_bytes(type_t *type);
> +

If we calculate the size during the symbol creation we don't have to
create this logic all over the places.  Other backends would reuse the
already preprocessed size in bytes.

>  void
>  codegen_linux_x86_64_init(codegen_x86_64_t *codegen, arena_t *arena, FILE *out)
>  {
> @@ -366,7 +369,7 @@ codegen_linux_x86_64_emit_block(codegen_x86_64_t *codegen, ast_block_t *block)
>                      codegen_linux_x86_64_emit_expression(codegen, var_def.value);
>                  }
>  
> -                codegen->base_offset += 8;
> +                codegen->base_offset += type_to_bytes(&symbol->type);
>                  size_t *offset = arena_alloc(codegen->arena, sizeof(size_t));
>                  *offset = codegen->base_offset;
>