patch-2.2.18 linux/arch/arm/nwfpe/fpa11_cpdo.c

• Lines: 118
• Date: Fri Sep 15 23:28:37 2000
• Orig file: v2.2.17/arch/arm/nwfpe/fpa11_cpdo.c
• Orig date: Thu Jan 1 01:00:00 1970

diff -u --new-file --recursive --exclude-from /usr/src/exclude v2.2.17/arch/arm/nwfpe/fpa11_cpdo.c linux/arch/arm/nwfpe/fpa11_cpdo.c
@@ -0,0 +1,117 @@
+/*
+    NetWinder Floating Point Emulator
+    (c) Corel Computer Corporation, 1998
+
+    Direct questions, comments to Scott Bambrough <scottb@corelcomputer.com>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "config.h"
+#include "fpa11.h"
+#include "fpopcode.h"
+
+unsigned int SingleCPDO(const unsigned int opcode);
+unsigned int DoubleCPDO(const unsigned int opcode);
+unsigned int ExtendedCPDO(const unsigned int opcode);
+
+unsigned int EmulateCPDO(const unsigned int opcode)
+{
+   unsigned int Fd, nType, nDest, nRc = 1;
+   
+   //fp_printk("EmulateCPDO(0x%08x)\n",opcode);
+
+   /* Get the destination size.  If not valid let Linux perform
+      an invalid instruction trap. */
+   nDest = getDestinationSize(opcode);
+   if (typeNone == nDest) return 0;
+   
+   SetRoundingMode(opcode);
+     
+   /* Compare the size of the operands in Fn and Fm.
+      Choose the largest size and perform operations in that size,
+      in order to make use of all the precision of the operands. 
+      If Fm is a constant, we just grab a constant of a size 
+      matching the size of the operand in Fn. */
+   if (MONADIC_INSTRUCTION(opcode))
+     nType = nDest;
+   else
+     nType = fpa11->fpreg[getFn(opcode)].fType;
+   
+   if (!CONSTANT_FM(opcode))
+   {
+     register unsigned int Fm = getFm(opcode);
+     if (nType < fpa11->fpreg[Fm].fType)
+     {
+        nType = fpa11->fpreg[Fm].fType;
+     }
+   }
+
+   switch (nType)
+   {
+      case typeSingle   : nRc = SingleCPDO(opcode);   break;
+      case typeDouble   : nRc = DoubleCPDO(opcode);   break;
+      case typeExtended : nRc = ExtendedCPDO(opcode); break;
+      default           : nRc = 0;
+   }
+
+   /* If the operation succeeded, check to see if the result in the
+      destination register is the correct size.  If not force it
+      to be. */
+   Fd = getFd(opcode);
+   nType = fpa11->fpreg[Fd].fType;
+   if ((0 != nRc) && (nDest != nType))
+   {
+     switch (nDest)
+     {
+       case typeSingle:
+       {
+         if (typeDouble == nType)
+           fpa11->fpreg[Fd].fValue.fSingle = 
+              float64_to_float32(fpa11->fpreg[Fd].fValue.fDouble);
+         else
+           fpa11->fpreg[Fd].fValue.fSingle = 
+              floatx80_to_float32(fpa11->fpreg[Fd].fValue.fExtended);
+       }
+       break;
+          
+       case typeDouble:
+       {
+         if (typeSingle == nType)
+           fpa11->fpreg[Fd].fValue.fDouble = 
+              float32_to_float64(fpa11->fpreg[Fd].fValue.fSingle);
+         else
+           fpa11->fpreg[Fd].fValue.fDouble = 
+              floatx80_to_float64(fpa11->fpreg[Fd].fValue.fExtended);
+       }
+       break;
+          
+       case typeExtended:
+       {
+         if (typeSingle == nType)
+           fpa11->fpreg[Fd].fValue.fExtended = 
+              float32_to_floatx80(fpa11->fpreg[Fd].fValue.fSingle);
+         else
+           fpa11->fpreg[Fd].fValue.fExtended = 
+              float64_to_floatx80(fpa11->fpreg[Fd].fValue.fDouble);
+       }
+       break;
+     }
+     
+     fpa11->fpreg[Fd].fType = nDest;
+   }
+   
+   return nRc;
+}