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Re: [tuples] dereference POINTER_PLUS_EXPR check
On Nov 21, 2007 10:52 PM, Aldy Hernandez <aldyh@redhat.com> wrote:
> > Maybe we could make this a helper in tree.c. Something like
> > pointed_to_type(). I don't think one exists already, but I may be wrong.
>
> Things are a bit cleaner now too, bonus!
>
> Is this OK?
No, sorry. It doesn't make sense to check the pointed-to types. Or do you
say the modify expr embeds a de-reference?
Richard.
> * tree.c (pointed_to_type): New.
> * tree.h (pointed_to_type): Protoize.
> * tree-cfg.c (verify_types_in_gimple_assign): Use the dereferenced
> type when checking the validity of a POINTER_PLUS_EXPR.
>
> Index: tree.c
> ===================================================================
> --- tree.c (revision 130313)
> +++ tree.c (working copy)
> @@ -8833,4 +8833,14 @@ block_nonartificial_location (tree block
> return ret;
> }
>
> +/* Given a tree type T, drill down to the type it points to and return
> + it. */
> +tree
> +pointed_to_type (tree t)
> +{
> + while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
> + t = TREE_TYPE (t);
> + return t;
> +}
> +
> #include "gt-tree.h"
> Index: tree.h
> ===================================================================
> --- tree.h (revision 130313)
> +++ tree.h (working copy)
> @@ -4918,6 +4918,7 @@ extern tree *tree_block (tree);
> extern tree *generic_tree_operand (tree, int);
> extern tree *generic_tree_type (tree);
> extern location_t *block_nonartificial_location (tree);
> +extern tree pointed_to_type (tree);
>
> /* In function.c */
> extern void expand_main_function (void);
> Index: tree-cfg.c
> ===================================================================
> --- tree-cfg.c (revision 130313)
> +++ tree-cfg.c (working copy)
> @@ -3558,8 +3558,16 @@ verify_types_in_gimple_assign (gimple st
> error ("invalid operands in pointer plus expression");
> return true;
> }
> - if (!POINTER_TYPE_P (rhs1_type)
> - || !useless_type_conversion_p (lhs_type, rhs1_type)
> +
> + if (!POINTER_TYPE_P (lhs_type)
> + || !POINTER_TYPE_P (rhs1_type))
> + {
> + error ("type mismatch in pointer plus expression");
> + return true;
> + }
> +
> + if (!useless_type_conversion_p (pointed_to_type (lhs_type),
> + pointed_to_type (rhs1_type))
> || !useless_type_conversion_p (sizetype, rhs2_type))
>
> {
> error ("type mismatch in pointer plus expression");
>