Re: [lto] remove rebuild_ssa_for_lto

[Diego Novillo <dnovillo at google dot com>]

Nathan Froyd wrote:

> @@ -735,6 +735,7 @@ input_expr_operand (struct input_block *
>  
>      case SSA_NAME:
>        result = VEC_index (tree, SSANAMES (fn), input_uleb128 (ib));
> +      add_referenced_var (SSA_NAME_VAR (result));

Since you're adding referenced vars as you read-in the body, it would be 
beneficial to gate pass_referenced_vars so that it doesn't re-scan the 
IL.  You'll save yourself a few cycles on the way in.


> +      /* Ensure that all our variables have annotations attached to them
> +	 so building SSA doesn't choke.  */
> +      {
> +	int i;
> +
> +	for (i = 0; i < header->num_var_decls; i++)
> +	  add_referenced_var (data_in.var_decls[i]);
> +	for (i =0; i < header->num_local_decls; i++)
> +	  add_referenced_var (data_in.local_decls[i]);

Haven't these been added while reading the IL?  In referenced_vars we 
should only have things that are explicitly mentioned in the body of the 
function.  If this loop is adding all the global/static vars, then it's 
adding too much.


Diego.