gdb/i387-tdep.c

   1 /* Intel 387 floating point stuff.
   2    Copyright (C) 1988, 1989, 1991, 1998 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "defs.h"
  22 #include "frame.h"
  23 #include "inferior.h"
  24 #include "language.h"
  25 #include "value.h"
  26 #include "gdbcore.h"
  27 #include "floatformat.h"
  28
  29 void i387_to_double PARAMS ((char *, char *));
  30 void double_to_i387 PARAMS ((char *, char *));
  31
  32 static void print_387_control_bits PARAMS ((unsigned int control));
  33 static void print_387_status_bits  PARAMS ((unsigned int status));
  34
  35 /* FIXME:  Eliminate these routines when we have the time to change all
  36    the callers.  */
  37
  38 void
  39 i387_to_double (from, to)
  40      char *from;
  41      char *to;
  42 {
  43   floatformat_to_double (&floatformat_i387_ext, from, (double *) to);
  44 }
  45
  46 void
  47 double_to_i387 (from, to)
  48      char *from;
  49      char *to;
  50 {
  51   floatformat_from_double (&floatformat_i387_ext, (double *) from, to);
  52 }
  53
  54 static void
  55 print_387_control_bits (control)
  56      unsigned int control;
  57 {
  58   switch ((control >> 8) & 3)
  59     {
  60     case 0:
  61       puts_unfiltered (" 24 bit; ");
  62       break;
  63     case 1:
  64       puts_unfiltered (" (bad); ");
  65       break;
  66     case 2:
  67       puts_unfiltered (" 53 bit; ");
  68       break;
  69     case 3:
  70       puts_unfiltered (" 64 bit; ");
  71       break;
  72     }
  73   switch ((control >> 10) & 3)
  74     {
  75     case 0:
  76       puts_unfiltered ("NEAR; ");
  77       break;
  78     case 1:
  79       puts_unfiltered ("DOWN; ");
  80       break;
  81     case 2:
  82       puts_unfiltered ("UP; ");
  83       break;
  84     case 3:
  85       puts_unfiltered ("CHOP; ");
  86       break;
  87     }
  88   if (control & 0x3f)
  89     {
  90       puts_unfiltered ("mask");
  91       if (control & 0x0001)
  92         puts_unfiltered (" INVAL");
  93       if (control & 0x0002)
  94         puts_unfiltered (" DENOR");
  95       if (control & 0x0004)
  96         puts_unfiltered (" DIVZ");
  97       if (control & 0x0008)
  98         puts_unfiltered (" OVERF");
  99       if (control & 0x0010)
 100         puts_unfiltered (" UNDER");
 101       if (control & 0x0020)
 102         puts_unfiltered (" LOS");
 103       puts_unfiltered (";");
 104     }
 105
 106   if (control & 0xe080)
 107     warning ("\nreserved bits on: %s",
 108              local_hex_string (control & 0xe080));
 109 }
 110
 111 void
 112 print_387_control_word (control)
 113      unsigned int control;
 114 {
 115   printf_filtered ("control %s:", local_hex_string(control & 0xffff));
 116   print_387_control_bits (control);
 117   puts_unfiltered ("\n");
 118 }
 119
 120 static void
 121 print_387_status_bits (status)
 122      unsigned int status;
 123 {
 124   printf_unfiltered (" flags %d%d%d%d; ",
 125                      (status & 0x4000) != 0,
 126                      (status & 0x0400) != 0,
 127                      (status & 0x0200) != 0,
 128                      (status & 0x0100) != 0);
 129   printf_unfiltered ("top %d; ", (status >> 11) & 7);
 130   if (status & 0xff)
 131     {
 132       puts_unfiltered ("excep");
 133       if (status & 0x0001) puts_unfiltered (" INVAL");
 134       if (status & 0x0002) puts_unfiltered (" DENOR");
 135       if (status & 0x0004) puts_unfiltered (" DIVZ");
 136       if (status & 0x0008) puts_unfiltered (" OVERF");
 137       if (status & 0x0010) puts_unfiltered (" UNDER");
 138       if (status & 0x0020) puts_unfiltered (" LOS");
 139       if (status & 0x0040) puts_unfiltered (" STACK");
 140     }
 141 }
 142
 143 void
 144 print_387_status_word (status)
 145      unsigned int status;
 146 {
 147   printf_filtered ("status %s:", local_hex_string (status & 0xffff));
 148   print_387_status_bits (status);
 149   puts_unfiltered ("\n");
 150 }
 151
 152 #ifdef LD_I387
 153 int
 154 i387_extract_floating (PTR addr, int len, DOUBLEST *dretptr)
 155 {
 156   if (len == TARGET_LONG_DOUBLE_BIT / 8)
 157     {
 158       if (HOST_LONG_DOUBLE_FORMAT == TARGET_LONG_DOUBLE_FORMAT)
 159         {
 160           DOUBLEST retval;
 161
 162           memcpy (dretptr, addr, sizeof (retval));
 163         }
 164       else
 165         floatformat_to_doublest (TARGET_LONG_DOUBLE_FORMAT, addr, dretptr);
 166
 167       return 1;
 168     }
 169   else
 170     return 0;
 171 }
 172
 173 int
 174 i387_store_floating (PTR addr, int len, DOUBLEST val)
 175 {
 176   if (len == TARGET_LONG_DOUBLE_BIT / 8)
 177     {
 178       /* This `if' may be totally stupid.  I just put it in here to be
 179          absolutely sure I'm preserving the semantics of the code I'm
 180          frobbing, while I try to maintain portability boundaries; I
 181          don't actually know exactly what it's doing.  -JimB, May 1999 */
 182       if (HOST_LONG_DOUBLE_FORMAT == TARGET_LONG_DOUBLE_FORMAT)
 183         memcpy (addr, &val, sizeof (val));
 184       else
 185         floatformat_from_doublest (TARGET_LONG_DOUBLE_FORMAT, &val, addr);
 186
 187       return 1;
 188     }
 189   else
 190     return 0;
 191 }
 192 #endif /* LD_I387 */