From c750e675cb77f283ff991682db7740bc5f6d4cf4 Mon Sep 17 00:00:00 2001
From: Andrew MacLeod <amacleod@redhat.com>
Date: Tue, 20 Sep 2022 19:05:03 -0400
Subject: [PATCH 15/17] Convert CFN_BUILT_IN_STRLEN to range-ops.
* gimple-range-fold.cc (range_of_builtin_int_call): Remove case
for CFN_BUILT_IN_STRLEN.
* gimple-range-op.cc (class cfn_strlen): New.
(gimple_range_op_handler::maybe_builtin_call): Set arguments.
---
gcc/gimple-range-fold.cc | 21 ---------------------
gcc/gimple-range-op.cc | 37 +++++++++++++++++++++++++++++++++++++
2 files changed, 37 insertions(+), 21 deletions(-)
@@ -908,27 +908,6 @@ fold_using_range::range_of_builtin_int_call (irange &r, gcall *call,
return true;
}
- case CFN_BUILT_IN_STRLEN:
- if (tree lhs = gimple_call_lhs (call))
- if (ptrdiff_type_node
- && (TYPE_PRECISION (ptrdiff_type_node)
- == TYPE_PRECISION (TREE_TYPE (lhs))))
- {
- tree type = TREE_TYPE (lhs);
- tree max = vrp_val_max (ptrdiff_type_node);
- wide_int wmax
- = wi::to_wide (max, TYPE_PRECISION (TREE_TYPE (max)));
- tree range_min = build_zero_cst (type);
- // To account for the terminating NULL, the maximum length
- // is one less than the maximum array size, which in turn
- // is one less than PTRDIFF_MAX (or SIZE_MAX where it's
- // smaller than the former type).
- // FIXME: Use max_object_size() - 1 here.
- tree range_max = wide_int_to_tree (type, wmax - 2);
- r.set (range_min, range_max);
- return true;
- }
- break;
default:
break;
}
@@ -611,6 +611,30 @@ cfn_ubsan op_cfn_ubsan_add (PLUS_EXPR);
cfn_ubsan op_cfn_ubsan_sub (MINUS_EXPR);
cfn_ubsan op_cfn_ubsan_mul (MULT_EXPR);
+
+// Implement range operator for CFN_BUILT_IN_STRLEN
+class cfn_strlen : public range_operator
+{
+public:
+ using range_operator::fold_range;
+ virtual bool fold_range (irange &r, tree type, const irange &,
+ const irange &, relation_kind) const
+ {
+ tree max = vrp_val_max (ptrdiff_type_node);
+ wide_int wmax
+ = wi::to_wide (max, TYPE_PRECISION (TREE_TYPE (max)));
+ tree range_min = build_zero_cst (type);
+ // To account for the terminating NULL, the maximum length
+ // is one less than the maximum array size, which in turn
+ // is one less than PTRDIFF_MAX (or SIZE_MAX where it's
+ // smaller than the former type).
+ // FIXME: Use max_object_size() - 1 here.
+ tree range_max = wide_int_to_tree (type, wmax - 2);
+ r.set (range_min, range_max);
+ return true;
+ }
+} op_cfn_strlen;
+
// Set up a gimple_range_op_handler for any built in function which can be
// supported via range-ops.
@@ -711,6 +735,19 @@ gimple_range_op_handler::maybe_builtin_call ()
m_int = &op_cfn_ubsan_mul;
break;
+ case CFN_BUILT_IN_STRLEN:
+ {
+ tree lhs = gimple_call_lhs (call);
+ if (lhs && ptrdiff_type_node && (TYPE_PRECISION (ptrdiff_type_node)
+ == TYPE_PRECISION (TREE_TYPE (lhs))))
+ {
+ m_op1 = gimple_call_arg (call, 0);
+ m_valid = true;
+ m_int = &op_cfn_strlen;
+ }
+ break;
+ }
+
default:
break;
}
--
2.37.3