FWIW $subject has a typo. While at it...
Am 03.09.2013 08:27, schrieb Aurelien Jarno:
> Known-zero bits optimization is a great idea that helps to generate more
> optimized code. However the current implementation is basically useless
> as the computed mask is not saved.
>
> Fix this to make it really working.
>
> Cc: Richard Henderson <r...@twiddle.net>
> Cc: Paolo Bonzini <pbonz...@redhat.com>
> Signed-off-by: Aurelien Jarno <aurel...@aurel32.net>
> ---
> tcg/optimize.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/tcg/optimize.c b/tcg/optimize.c
> index b29bf25..41f2906 100644
> --- a/tcg/optimize.c
> +++ b/tcg/optimize.c
> @@ -695,7 +695,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s,
> uint16_t *tcg_opc_ptr,
> break;
> }
>
> - /* Simplify using known-zero bits */
> + /* Simplify using known-zero bits. Currently only ops with a single
> + output argument is supported. */
"ops ... are"?
Cheers,
Andreas
> mask = -1;
> affected = -1;
> switch (op) {
> @@ -1144,6 +1145,11 @@ static TCGArg *tcg_constant_folding(TCGContext *s,
> uint16_t *tcg_opc_ptr,
> } else {
> for (i = 0; i < def->nb_oargs; i++) {
> reset_temp(args[i]);
> + /* Save the corresponding known-zero bits mask for the
> + first output argument (only one supported so far). */
> + if (i == 0) {
> + temps[args[i]].mask = mask;
> + }
> }
> }
> for (i = 0; i < def->nb_args; i++) {
>
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