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-rw-r--r--gcc/range-op.cc16
-rw-r--r--gcc/testsuite/g++.dg/pr96707.C10
2 files changed, 26 insertions, 0 deletions
diff --git a/gcc/range-op.cc b/gcc/range-op.cc
index a4f6e9e..19bdf30 100644
--- a/gcc/range-op.cc
+++ b/gcc/range-op.cc
@@ -1941,9 +1941,25 @@ public:
const irange &lhs,
const irange &op2,
relation_kind rel = VREL_NONE) const;
+ virtual enum tree_code lhs_op1_relation (const irange &lhs,
+ const irange &op1,
+ const irange &op2) const;
} op_rshift;
+enum tree_code
+operator_rshift::lhs_op1_relation (const irange &lhs ATTRIBUTE_UNUSED,
+ const irange &op1,
+ const irange &op2) const
+{
+ // If both operands range are >= 0, then the LHS <= op1.
+ if (!op1.undefined_p () && !op2.undefined_p ()
+ && wi::ge_p (op1.lower_bound (), 0, TYPE_SIGN (op1.type ()))
+ && wi::ge_p (op2.lower_bound (), 0, TYPE_SIGN (op2.type ())))
+ return LE_EXPR;
+ return VREL_NONE;
+}
+
bool
operator_lshift::fold_range (irange &r, tree type,
const irange &op1,
diff --git a/gcc/testsuite/g++.dg/pr96707.C b/gcc/testsuite/g++.dg/pr96707.C
new file mode 100644
index 0000000..2653fe3
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr96707.C
@@ -0,0 +1,10 @@
+/* { dg-do compile} */
+/* { dg-options "-O2 -fdump-tree-evrp" } */
+
+bool f(unsigned x, unsigned y)
+{
+ return (x >> y) <= x;
+}
+
+/* { dg-final { scan-tree-dump "return 1" "evrp" } } */
+