0.9.12.11:

[sbcl.git] / src / compiler / generic / genesis.lisp

diff --git a/src/compiler/generic/genesis.lisp b/src/compiler/generic/genesis.lisp
index 33a504b..f703646 100644 (file)
--- a/src/compiler/generic/genesis.lisp
+++ b/src/compiler/generic/genesis.lisp
@@ -1747,8 +1747,7 @@ core and return a descriptor to it."
           (setf (bvref-32 gspace-bytes gspace-byte-offset)
                 (logior (mask-field (byte 16 16)
                                     (bvref-32 gspace-bytes gspace-byte-offset))
-                        (+ (ash value -16)
-                           (if (logbitp 15 value) 1 0)))))
+                        (ash (1+ (ldb (byte 17 15) value)) -1))))
          (:addi
           (setf (bvref-32 gspace-bytes gspace-byte-offset)
                 (logior (mask-field (byte 16 16)