X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;ds=sidebyside;f=src%2Fcode%2Fcross-float.lisp;h=f7b995eb32202e7aedb66ccd31abe2a0f8091414;hb=1c91b0bc7eb814af6a8c58a99a83a024716138e8;hp=e0b2eb009f751ef30ca55d88f348a30b310c289a;hpb=22b819c0cd0ca0ea5be52ba280b9e9e0b8e86210;p=sbcl.git

diff --git a/src/code/cross-float.lisp b/src/code/cross-float.lisp
index e0b2eb0..f7b995e 100644
--- a/src/code/cross-float.lisp
+++ b/src/code/cross-float.lisp
@@ -214,13 +214,18 @@
     ;; IEEE float special cases
     ((zerop bits) 0.0)
     ((= bits #x-80000000) -0.0)
-    (t (let ((sign (ecase (ldb (byte 1 31) bits)
-		     (0  1.0)
-		     (1 -1.0)))
-	     (expt (- (ldb (byte 8 23) bits) 127))
-	     (mant (* (logior (ldb (byte 23 0) bits)
-			      (ash 1 23))
-		      (expt 0.5 23))))
+    (t (let* ((sign (ecase (ldb (byte 1 31) bits)
+                      (0  1.0)
+                      (1 -1.0)))
+              (iexpt (ldb (byte 8 23) bits))
+              (expt (if (zerop iexpt) ; denormalized
+                        -126
+                        (- iexpt 127)))
+              (mant (* (logior (ldb (byte 23 0) bits)
+                               (if (zerop iexpt)
+                                   0
+                                   (ash 1 23)))
+                       (expt 0.5 23))))
 	 (* sign (kludge-opaque-expt 2.0 expt) mant)))))
 
 (defun make-double-float (hi lo)
@@ -232,9 +237,14 @@
 	      (sign (ecase (ldb (byte 1 63) bits)
 		      (0  1.0d0)
 		      (1 -1.0d0)))
-	      (expt (- (ldb (byte 11 52) bits) 1023))
+              (iexpt (ldb (byte 11 52) bits))
+	      (expt (if (zerop iexpt) ; denormalized
+                        -1022
+                        (- iexpt 1023)))
 	      (mant (* (logior (ldb (byte 52 0) bits)
-			       (ash 1 52))
+			       (if (zerop iexpt)
+                                   0
+                                   (ash 1 52)))
 		       (expt 0.5d0 52))))
 	 (* sign (kludge-opaque-expt 2.0d0 expt) mant)))))