2012-12-14 Yufeng Zhang <yufeng.zhang@arm.com>

[deliverable/binutils-gdb.git] / gdb / doublest.c

diff --git a/gdb/doublest.c b/gdb/doublest.c
index 0739fdb91a03500647fa5837553bb45e508c0597..0308dac619009d5eab81f2f0b0a5772970045e79 100644 (file)
--- a/gdb/doublest.c
+++ b/gdb/doublest.c
@@ -1,8 +1,7 @@
 /* Floating point routines for GDB, the GNU debugger.
 
-   Copyright (C) 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
-   1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2007, 2008, 2009, 2010,
-   2011 Free Software Foundation, Inc.
+   Copyright (C) 1986, 1988-2001, 2003-2005, 2007-2012 Free Software
+   Foundation, Inc.
 
    This file is part of GDB.
 
@@ -473,6 +472,28 @@ convert_doublest_to_floatformat (CONST struct floatformat *fmt,
   mant = frexp (dfrom, &exponent);
 #endif
 
+  if (exponent + fmt->exp_bias <= 0)
+    {
+      /* The value is too small to be expressed in the destination
+        type (not enough bits in the exponent.  Treat as 0.  */
+      put_field (uto, order, fmt->totalsize, fmt->exp_start,
+                fmt->exp_len, 0);
+      put_field (uto, order, fmt->totalsize, fmt->man_start,
+                fmt->man_len, 0);
+      goto finalize_byteorder;
+    }
+
+  if (exponent + fmt->exp_bias >= (1 << fmt->exp_len))
+    {
+      /* The value is too large to fit into the destination.
+        Treat as infinity.  */
+      put_field (uto, order, fmt->totalsize, fmt->exp_start,
+                fmt->exp_len, fmt->exp_nan);
+      put_field (uto, order, fmt->totalsize, fmt->man_start,
+                fmt->man_len, 0);
+      goto finalize_byteorder;
+    }
+
   put_field (uto, order, fmt->totalsize, fmt->exp_start, fmt->exp_len,
             exponent + fmt->exp_bias - 1);