Re: [RFA] Fix pending register stores in mips simulator

[Andrew Cagney <ac131313@cygnus.com>]

Jim Blandy wrote:
> 
> Without this patch, the CFC1 and CTC1 instructions queue pending
> register stores off the end of the register array.  In my test
> program, this ended up up zeroing elements in the CPU's register_width
> array.  The sim refuse to provide the values of the registers whose
> widths are zero, which confuses GDB.
> 
> 2001-04-04  Jim Blandy  <jimb@redhat.com>
> 
>         * mips.igen (CFC1, CTC1): Pass the correct register numbers to
>         PENDING_FILL.  Use PENDING_SCHED directly to handle the pending
>         set of the FCSR.
>         * sim-main.h (COCIDX): Remove definition; this isn't supported by
>         PENDING_FILL, and you can get the intended effect gracefully by
>         calling PENDING_SCHED directly.

Yes, thansk.
	Andrew

> Index: sim/mips/mips.igen
> ===================================================================
> RCS file: /cvs/cvsfiles/devo/sim/mips/mips.igen,v
> retrieving revision 1.86.72.1
> diff -c -r1.86.72.1 mips.igen
> *** sim/mips/mips.igen  2001/01/25 08:33:38     1.86.72.1
> --- sim/mips/mips.igen  2001/04/05 03:05:08
> ***************
> *** 2967,2977 ****
>     if (X)
>       {
>         if (FS == 0)
> !       PENDING_FILL((FS + FCR0IDX),VL4_8(GPR[RT]));
>         else if (FS == 31)
> !       PENDING_FILL((FS + FCR31IDX),VL4_8(GPR[RT]));
>         /* else NOP */
> !       PENDING_FILL(COCIDX,0); /* special case */
>       }
>     else
>       { /* control from */
> --- 2967,2977 ----
>     if (X)
>       {
>         if (FS == 0)
> !       PENDING_FILL(FCR0IDX,VL4_8(GPR[RT]));
>         else if (FS == 31)
> !       PENDING_FILL(FCR31IDX,VL4_8(GPR[RT]));
>         /* else NOP */
> !       PENDING_SCHED(FCSR, FCR31 & (1<<23), 1, 23);
>       }
>     else
>       { /* control from */
> Index: sim/mips/sim-main.h
> ===================================================================
> RCS file: /cvs/cvsfiles/devo/sim/mips/sim-main.h,v
> retrieving revision 1.88.40.1
> diff -c -r1.88.40.1 sim-main.h
> *** sim/mips/sim-main.h 2001/01/25 08:33:39     1.88.40.1
> --- sim/mips/sim-main.h 2001/04/05 03:05:09
> ***************
> *** 404,410 ****
>   #define Debug (REGISTERS[86])
>   #define DEPC  (REGISTERS[87])
>   #define EPC   (REGISTERS[88])
> - #define COCIDX  (LAST_EMBED_REGNUM + 2) /* special case : outside the normal range */
> 
>     /* All internal state modified by signal_exception() that may need to be
>        rolled back for passing moment-of-exception image back to gdb. */
> --- 404,409 ----