[Qemu-devel] [6054] target-ppc: enable PRECISE_EMULATION by default

[Qemu-devel] [6054] target-ppc: enable PRECISE_EMULATION by default

[Aurelien Jarno]

Revision: 6054
          http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=6054
Author:   aurel32
Date:     2008-12-15 17:14:50 +0000 (Mon, 15 Dec 2008)

Log Message:
-----------
target-ppc: enable PRECISE_EMULATION by default

With this option enabled, all glibc math tests pass.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

Modified Paths:
--------------
    trunk/target-ppc/exec.h

Modified: trunk/target-ppc/exec.h
===================================================================
--- trunk/target-ppc/exec.h	2008-12-15 17:14:43 UTC (rev 6053)
+++ trunk/target-ppc/exec.h	2008-12-15 17:14:50 UTC (rev 6054)
@@ -29,7 +29,7 @@
 
 /* For normal operations, precise emulation should not be needed */
 //#define USE_PRECISE_EMULATION 1
-#define USE_PRECISE_EMULATION 0
+#define USE_PRECISE_EMULATION 1
 
 register struct CPUPPCState *env asm(AREG0);
 #define TDX "%016" PRIx64

Re: [Qemu-devel] [6054] target-ppc: enable PRECISE_EMULATION by default

[Laurent Desnogues]

On Mon, Dec 15, 2008 at 6:14 PM, Aurelien Jarno <aurelien@aurel32.net> wrote:
> Revision: 6054
>          http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=6054
> Author:   aurel32
> Date:     2008-12-15 17:14:50 +0000 (Mon, 15 Dec 2008)
>
> Log Message:
> -----------
> target-ppc: enable PRECISE_EMULATION by default
>
> With this option enabled, all glibc math tests pass.
[...]
>  /* For normal operations, precise emulation should not be needed */
>  //#define USE_PRECISE_EMULATION 1
> -#define USE_PRECISE_EMULATION 0
> +#define USE_PRECISE_EMULATION 1

Shouldn't you change the comment too so that one can track
why USE_PRECISE_EMULATION is needed?


Laurent

Re: [Qemu-devel] [6054] target-ppc: enable PRECISE_EMULATION by default

[Aurelien Jarno]

On Mon, Dec 15, 2008 at 06:57:39PM +0100, Laurent Desnogues wrote:
> On Mon, Dec 15, 2008 at 6:14 PM, Aurelien Jarno <aurelien@aurel32.net> wrote:
> > Revision: 6054
> >          http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=6054
> > Author:   aurel32
> > Date:     2008-12-15 17:14:50 +0000 (Mon, 15 Dec 2008)
> >
> > Log Message:
> > -----------
> > target-ppc: enable PRECISE_EMULATION by default
> >
> > With this option enabled, all glibc math tests pass.
> [...]
> >  /* For normal operations, precise emulation should not be needed */
> >  //#define USE_PRECISE_EMULATION 1
> > -#define USE_PRECISE_EMULATION 0
> > +#define USE_PRECISE_EMULATION 1
> 
> Shouldn't you change the comment too so that one can track
> why USE_PRECISE_EMULATION is needed?

That is fixed in revision 6058. BTW I wonder if we should really
maintain two versions of the code that in most case only differs 
by a few checks on the operand. Those checks are a and operation
followed by a comparison, so they probably take very few time compared
to the actual computation.

Any opinion?

-- 
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 : :' :  Debian developer           | Electrical Engineer
 `. `'   aurel32@debian.org         | aurelien@aurel32.net
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