patch-2.1.73 linux/arch/i386/math-emu/reg_convert.c

• Lines: 54
• Date: Tue Dec 9 17:57:09 1997
• Orig file: v2.1.72/linux/arch/i386/math-emu/reg_convert.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.72/linux/arch/i386/math-emu/reg_convert.c linux/arch/i386/math-emu/reg_convert.c
@@ -0,0 +1,53 @@
+/*---------------------------------------------------------------------------+
+ |  reg_convert.c                                                            |
+ |                                                                           |
+ |  Convert register representation.                                         |
+ |                                                                           |
+ | Copyright (C) 1992,1993,1994,1996,1997                                    |
+ |                  W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia |
+ |                  E-mail   billm@suburbia.net                              |
+ |                                                                           |
+ |                                                                           |
+ +---------------------------------------------------------------------------*/
+
+#include "exception.h"
+#include "fpu_emu.h"
+
+
+int FPU_to_exp16(FPU_REG const *a, FPU_REG *x)
+{
+  int sign = getsign(a);
+
+  *(long long *)&(x->sigl) = *(const long long *)&(a->sigl);
+
+  /* Set up the exponent as a 16 bit quantity. */
+  setexponent16(x, exponent(a));
+
+  if ( exponent16(x) == EXP_UNDER )
+    {
+      /* The number is a de-normal or pseudodenormal. */
+      /* We only deal with the significand and exponent. */
+
+      if (x->sigh & 0x80000000)
+	{
+	  /* Is a pseudodenormal. */
+	  /* This is non-80486 behaviour because the number
+	     loses its 'denormal' identity. */
+	  addexponent(x, 1);
+	}
+      else
+	{
+	  /* Is a denormal. */
+	  addexponent(x, 1);
+	  FPU_normalize_nuo(x);
+	}
+    }
+
+  if ( !(x->sigh & 0x80000000) )
+    {
+      EXCEPTION(EX_INTERNAL | 0x180);
+    }
+
+  return sign;
+}
+