Change the name of array_at_struct_end_p to array_ref_flexible_size_p

The name of the utility routine "array_at_struct_end_p" is misleading
and should be changed to a new name that more accurately reflects its
real meaning.

The routine "array_at_struct_end_p" is used to check whether an array
reference is to an array whose actual size might be larger than its
upper bound implies, which includes 3 different cases:

   A. a ref to a flexible array member at the end of a structure;
   B. a ref to an array with a different type against the original decl;
   C. a ref to an array that was passed as a parameter;

The old name only reflects the above case A, therefore very confusing
when reading the corresponding gcc source code.

In this patch, A new name "array_ref_flexible_size_p" is used to replace
the old name.

All the references to the routine "array_at_struct_end_p" was replaced
with this new name, and the corresponding comments were updated to make
them clean and consistent.

gcc/ChangeLog:

	* gimple-array-bounds.cc (trailing_array): Replace
	array_at_struct_end_p with new name and update comments.
	* gimple-fold.cc (get_range_strlen_tree): Likewise.
	* gimple-ssa-warn-restrict.cc (builtin_memref::builtin_memref):
	Likewise.
	* graphite-sese-to-poly.cc (bounds_are_valid): Likewise.
	* tree-if-conv.cc (idx_within_array_bound): Likewise.
	* tree-object-size.cc (addr_object_size): Likewise.
	* tree-ssa-alias.cc (component_ref_to_zero_sized_trailing_array_p):
	Likewise.
	(stmt_kills_ref_p): Likewise.
	* tree-ssa-loop-niter.cc (idx_infer_loop_bounds): Likewise.
	* tree-ssa-strlen.cc (maybe_set_strlen_range): Likewise.
	* tree.cc (array_at_struct_end_p): Rename to ...
	(array_ref_flexible_size_p): ... this.
	(component_ref_size): Replace array_at_struct_end_p with new name.
	* tree.h (array_at_struct_end_p): Rename to ...
	(array_ref_flexible_size_p): ... this.

1 files changed, 2 insertions, 2 deletions

diff --git a/gcc/gimple-array-bounds.cc b/gcc/gimple-array-bounds.cc
index e190b93..fbf448e 100644
--- a/gcc/gimple-array-bounds.cc
+++ b/gcc/gimple-array-bounds.cc
@@ -129,7 +129,7 @@ get_ref_size (tree arg, tree *pref)
 }
 
 /* Return true if REF is (likely) an ARRAY_REF to a trailing array member
-   of a struct.  It refines array_at_struct_end_p by detecting a pointer
+   of a struct.  It refines array_ref_flexible_size_p by detecting a pointer
    to an array and an array parameter declared using the [N] syntax (as
    opposed to a pointer) and returning false.  Set *PREF to the decl or
    expression REF refers to.  */
@@ -167,7 +167,7 @@ trailing_array (tree arg, tree *pref)
 	return false;
     }
 
-  return array_at_struct_end_p (arg);
+  return array_ref_flexible_size_p (arg);
 }
 
 /* Checks one ARRAY_REF in REF, located at LOCUS. Ignores flexible