From: Andrew MacLeod <amacleod@redhat.com>
Date: Tue, 10 Jun 2025 16:11:18 +0000 (-0400)
Subject: Check if constant is a member before returning it.
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6a4da727020b24b02b062f4bff718c9a5699629c;p=thirdparty%2Fgcc.git

Check if constant is a member before returning it.

set_range_from_bitmask checks the new bitmask, and if it is a constant,
simply returns the constant.  It never checks if that constant is
actually within the range.  If it is not, the result should be UNDEFINED.

	* value-range.cc (irange::set_range_from_bitmask): When the bitmask
	result is a singleton, check if it is contained in the range.
---

diff --git a/gcc/value-range.cc b/gcc/value-range.cc
index ed3760fa6ff..e2d75f59c2e 100644
--- a/gcc/value-range.cc
+++ b/gcc/value-range.cc
@@ -2268,7 +2268,11 @@ irange::set_range_from_bitmask ()
   // If all the bits are known, this is a singleton.
   if (m_bitmask.mask () == 0)
     {
-      set (m_type, m_bitmask.value (), m_bitmask.value ());
+      // Make sure the singleton is within the range.
+      if (contains_p (m_bitmask.value ()))
+	set (m_type, m_bitmask.value (), m_bitmask.value ());
+      else
+	set_undefined ();
       return true;
     }