Restored my fixes for printing the FP registers. Their

history was lost with FreeBSD-1.x and they were blown away
by the gdb-4.16 merge.  I needed this to debug e_exp.S ...

Restored even older code (from 386BSD-0.0) for converting the
FP registers to doubles.  floatformat_to_double() and/or
valprint() still don't understand NaNs.

Removed unnecessary #include of obsolete <sys/dir.h> again.
This commit is contained in:
Bruce Evans 1997-02-15 17:09:00 +00:00
parent 6e0a4251e7
commit 4f69a041d5
1 changed files with 41 additions and 6 deletions

View File

@ -150,7 +150,6 @@ i386_register_u_addr (blockend, regnum)
#include "floatformat.h"
#include <sys/param.h>
#include <sys/dir.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <fcntl.h>
@ -173,6 +172,37 @@ extern void print_387_status_word ();
#define fpstate save87
#define U_FPSTATE(u) u.u_pcb.pcb_savefpu
static void
i387_to_double (from, to)
char *from;
char *to;
{
long *lp;
/* push extended mode on 387 stack, then pop in double mode
*
* first, set exception masks so no error is generated -
* number will be rounded to inf or 0, if necessary
*/
asm ("pushl %eax"); /* grab a stack slot */
asm ("fstcw (%esp)"); /* get 387 control word */
asm ("movl (%esp),%eax"); /* save old value */
asm ("orl $0x3f,%eax"); /* mask all exceptions */
asm ("pushl %eax");
asm ("fldcw (%esp)"); /* load new value into 387 */
asm ("movl 8(%ebp),%eax");
asm ("fldt (%eax)"); /* push extended number on 387 stack */
asm ("fwait");
asm ("movl 12(%ebp),%eax");
asm ("fstpl (%eax)"); /* pop double */
asm ("fwait");
asm ("popl %eax"); /* flush modified control word */
asm ("fnclex"); /* clear exceptions */
asm ("fldcw (%esp)"); /* restore original control word */
asm ("popl %eax"); /* flush saved copy */
}
struct env387
{
unsigned short control;
@ -225,12 +255,18 @@ print_387_status (status, ep)
top = (ep->status >> 11) & 7;
printf_unfiltered ("regno tag msb lsb value\n");
printf_unfiltered (" regno tag msb lsb value\n");
for (fpreg = 7; fpreg >= 0; fpreg--)
{
int st_regno;
double val;
printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : " ", fpreg);
/* The physical regno `fpreg' is only relevant as an index into the
* tag word. Logical `%st' numbers are required for indexing ep->regs.
*/
st_regno = (fpreg + 8 - top) & 7;
printf_unfiltered ("%%st(%d) %s ", st_regno, fpreg == top ? "=>" : " ");
switch ((ep->tag >> (fpreg * 2)) & 3)
{
@ -240,10 +276,9 @@ print_387_status (status, ep)
case 3: printf_unfiltered ("empty "); break;
}
for (i = 9; i >= 0; i--)
printf_unfiltered ("%02x", ep->regs[fpreg][i]);
printf_unfiltered ("%02x", ep->regs[st_regno][i]);
floatformat_to_double(&floatformat_i387_ext, (char *) ep->regs[fpreg],
&val);
i387_to_double((char *) ep->regs[st_regno], (char *) &val);
printf_unfiltered (" %g\n", val);
}
}