Remove now-unnecessary expr_skeletont methods

These are unused now that we don't have shift_indexed_access_to_lhs or rewrite_with_to_field_symbols

Author: smowton

src/goto-symex/expr_skeleton.cpp

@@ -52,51 +52,3 @@ expr_skeletont expr_skeletont::compose(expr_skeletont other) const
 {
   return expr_skeletont(apply(other.skeleton));
 }
-
-/// In the expression corresponding to a skeleton returns a pointer to the
-/// deepest subexpression before we encounter nil.
-static exprt *deepest_not_nil(exprt &e)
-{
-  exprt *ptr = &e;
-  while(!ptr->op0().is_nil())
-    ptr = &ptr->op0();
-  return ptr;
-}
-
-optionalt<expr_skeletont>
-expr_skeletont::clear_innermost_index_expr(expr_skeletont skeleton)
-{
-  exprt *to_update = deepest_not_nil(skeleton.skeleton);
-  if(index_exprt *index_expr = expr_try_dynamic_cast<index_exprt>(*to_update))
-  {
-    index_expr->make_nil();
-    return expr_skeletont{std::move(skeleton)};
-  }
-  return {};
-}
-
-optionalt<expr_skeletont>
-expr_skeletont::clear_innermost_member_expr(expr_skeletont skeleton)
-{
-  exprt *to_update = deepest_not_nil(skeleton.skeleton);
-  if(member_exprt *member = expr_try_dynamic_cast<member_exprt>(*to_update))
-  {
-    member->make_nil();
-    return expr_skeletont{std::move(skeleton)};
-  }
-  return {};
-}
-
-optionalt<expr_skeletont>
-expr_skeletont::clear_innermost_byte_extract_expr(expr_skeletont skeleton)
-{
-  exprt *to_update = deepest_not_nil(skeleton.skeleton);
-  if(
-    to_update->id() != ID_byte_extract_big_endian &&
-    to_update->id() != ID_byte_extract_little_endian)
-  {
-    return {};
-  }
-  to_update->make_nil();
-  return expr_skeletont{std::move(skeleton.skeleton)};
-}

src/goto-symex/expr_skeleton.h

@@ -43,24 +43,6 @@ class expr_skeletont final
   /// `array2[index]`.
   static expr_skeletont remove_op0(exprt e);
 
-  /// If the deepest subexpression in the skeleton is a member expression,
-  /// replace it with a nil expression and return the obtained skeleton.
-  static optionalt<expr_skeletont>
-  clear_innermost_index_expr(expr_skeletont skeleton);
-
-  /// If the deepest subexpression in the skeleton is a member expression,
-  /// replace it with a nil expression and return the obtained skeleton.
-  static optionalt<expr_skeletont>
-  clear_innermost_member_expr(expr_skeletont skeleton);
-
-  /// If the deepest subexpression in the skeleton is a byte-extract expression,
-  /// replace it with a nil expression and return the obtained skeleton.
-  /// For instance, for `(byte_extract(☐, 2, int)).field[index]`
-  /// `☐.field[index]` is returned, while for `byte_extract(☐.field, 2, int)`
-  /// an empty optional is returned.
-  static optionalt<expr_skeletont>
-  clear_innermost_byte_extract_expr(expr_skeletont skeleton);
-
 private:
   /// In \c skeleton, nil_exprt is used to mark the sub expression to be
   /// substituted. The nil_exprt always appears recursively following the first