1 files changed, 10 insertions, 0 deletions
diff --git a/gdbsupport/common-utils.h b/gdbsupport/common-utils.h
index a168458..10bf9f4 100644
--- a/gdbsupport/common-utils.h
+++ b/gdbsupport/common-utils.h
@@ -196,6 +196,16 @@ in_inclusive_range (T value, T low, T high)
 extern ULONGEST align_up (ULONGEST v, int n);
 extern ULONGEST align_down (ULONGEST v, int n);
 
+/* Sign-extend the value V, using N as the number of valid bits.  That
+   is, bit N-1 is the sign bit.  The higher-order bits (those outside
+   0..N-1) must be zero.  */
+static inline ULONGEST
+sign_extend (ULONGEST v, int n)
+{
+  ULONGEST mask = (ULONGEST) 1 << (n - 1);
+  return (v ^ mask) - mask;
+}
+
 /* Convert hex digit A to a number, or throw an exception.  */
 extern int fromhex (int a);