* i387-nat.h, i387-nat.c: New files.

3 files changed, 166 insertions, 0 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index b6e9a24..51fc8a6 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2000-05-24  Mark Kettenis  <kettenis@gnu.org>
+
+	* i387-nat.h, i387-nat.c: New files.
+
 Tue May 23 17:21:24 2000  Alexandre Oliva  <aoliva@cygnus.com>
 
 	* config/sparc/nm-linux.h: Include config/nm-linux.h.
diff --git a/gdb/i387-nat.c b/gdb/i387-nat.c
new file mode 100644
index 0000000..17e67b4
--- /dev/null
+++ b/gdb/i387-nat.c
@@ -0,0 +1,125 @@
+/* Native-dependent code for the i387.
+   Copyright (C) 2000 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   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., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include "defs.h"
+#include "inferior.h"
+#include "value.h"
+
+/* FIXME: kettenis/2000-05-21: Right now more than a few i386 targets
+   define their own routines to manage the floating-point registers in
+   GDB's register array.  Most (if not all) of these targets use the
+   format used by the "fsave" instruction in their communication with
+   the OS.  They should all be converted to use the routines below.  */
+
+/* At fsave_offset[REGNO] you'll find the offset to the location in
+   the data structure used by the "fsave" instruction where GDB
+   register REGNO is stored.  */
+
+static int fsave_offset[] =
+{
+  28 + 0 * FPU_REG_RAW_SIZE,	/* FP0_REGNUM through ...  */
+  28 + 1 * FPU_REG_RAW_SIZE,  
+  28 + 2 * FPU_REG_RAW_SIZE,  
+  28 + 3 * FPU_REG_RAW_SIZE,  
+  28 + 4 * FPU_REG_RAW_SIZE,  
+  28 + 5 * FPU_REG_RAW_SIZE,  
+  28 + 6 * FPU_REG_RAW_SIZE,  
+  28 + 7 * FPU_REG_RAW_SIZE,	/* ... FP7_REGNUM.  */
+  0,				/* FCTRL_REGNUM (16 bits).  */
+  4,				/* FSTAT_REGNUM (16 bits).  */
+  8,				/* FTAG_REGNUM (16 bits).  */
+  16,				/* FCS_REGNUM (16 bits).  */
+  12,				/* FCOFF_REGNUM.  */
+  24,				/* FDS_REGNUM.  */
+  20,				/* FDOFF_REGNUM.  */
+  18				/* FOP_REGNUM (bottom 11 bits).  */
+};
+
+#define FSAVE_ADDR(fsave, regnum) (fsave + fsave_offset[regnum - FP0_REGNUM])
+
+
+/* Fill GDB's register array with the floating-point register values
+   in *FSAVE.  This function masks off any of the reserved
+   bits in *FSAVE.  */
+
+void
+i387_supply_fsave (char *fsave)
+{
+  int i;
+
+  for (i = FP0_REGNUM; i <= LAST_FPU_CTRL_REGNUM; i++)
+    {
+      /* Most of the FPU control registers occupy only 16 bits in
+	 the fsave area.  Give those a special treatment.  */
+      if (i >= FIRST_FPU_CTRL_REGNUM
+	  && i != FCOFF_REGNUM && i != FDOFF_REGNUM)
+	{
+	  unsigned val = *(unsigned short *) (FSAVE_ADDR (fsave, i));
+
+	  if (i == FOP_REGNUM)
+	    {
+	      val &= ((1 << 11) - 1);
+	      supply_register (i, (char *) &val);
+	    }
+	  else
+	    supply_register (i, (char *) &val);
+	}
+      else
+	supply_register (i, FSAVE_ADDR (fsave, i));
+    }
+}
+
+/* Fill register REGNO (if it is a floating-point register) in *FSAVE
+   with the value in GDB's register array.  If REGNO is -1, do this
+   for all registers.  This function doesn't touch any of the reserved
+   bits in *FSAVE.  */
+
+void
+i387_fill_fsave (char *fsave, int regno)
+{
+  int i;
+
+  for (i = FP0_REGNUM; i <= LAST_FPU_CTRL_REGNUM; i++)
+    if (regno == -1 || regno == i)
+      {
+	/* Most of the FPU control registers occupy only 16 bits in
+           the fsave area.  Give those a special treatment.  */
+	if (i >= FIRST_FPU_CTRL_REGNUM
+	    && i != FCOFF_REGNUM && i != FDOFF_REGNUM)
+	  {
+	    if (i == FOP_REGNUM)
+	      {
+		unsigned short oldval, newval;
+
+		/* The opcode occupies only 11 bits.  */
+		oldval = (*(unsigned short *) (FSAVE_ADDR (fsave, i)));
+		newval = *(unsigned short *) &registers[REGISTER_BYTE (i)];
+		newval &= ((1 << 11) - 1);
+		newval |= oldval & ~((1 << 11) - 1);
+		memcpy (FSAVE_ADDR (fsave, i), &newval, 2);
+	      }
+	    else
+	      memcpy (FSAVE_ADDR (fsave, i), &registers[REGISTER_BYTE (i)], 2);
+	  }
+	else
+	  memcpy (FSAVE_ADDR (fsave, i), &registers[REGISTER_BYTE (i)],
+		  REGISTER_RAW_SIZE (i));
+      }
+}
diff --git a/gdb/i387-nat.h b/gdb/i387-nat.h
new file mode 100644
index 0000000..c23c267
--- /dev/null
+++ b/gdb/i387-nat.h
@@ -0,0 +1,37 @@
+/* Native-dependent code for the i387.
+   Copyright (C) 2000 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   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., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#ifndef I387_NAT_H
+#define I387_NAT_H
+
+/* Fill GDB's register array with the floating-point register values
+   in *FSAVE.  This function masks off any of the reserved
+   bits in *FSAVE.  */
+
+void i387_supply_fsave (char *fsave);
+
+/* Fill register REGNO (if it is a floating-point register) in *FSAVE
+   with the value in GDB's register array.  If REGNO is -1, do this
+   for all registers.  This function doesn't touch any of the reserved
+   bits in *FSAVE.  */
+
+void i387_fill_fsave (char *fsave, int regno);
+
+#endif /* i387-nat.h */