Re: [PATCH 17/28] tcg: Add flags argument to tcg_gen_bswap16_*, tcg_gen_bswap32_i64

[Richard Henderson]

On 6/14/21 2:41 AM, Philippe Mathieu-Daudé wrote:
> On 6/14/21 10:37 AM, Richard Henderson wrote:
> > Implement the new semantics in the fallback expansion.
> > Change all callers to supply the flags that keep the
> > semantics unchanged locally.
> >
> > Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> > ---
> >   include/tcg/tcg-op.h            |   8 +--
> >   target/arm/translate-a64.c      |  12 ++--
> >   target/arm/translate.c          |   2 +-
> >   target/i386/tcg/translate.c     |   2 +-
> >   target/mips/tcg/mxu_translate.c |   2 +-
> >   target/s390x/translate.c        |   4 +-
> >   target/sh4/translate.c          |   2 +-
>
> Various REV 16/32, would it be useful to have it as a TCG opcode?

Which operation are you proposing as tcg opcode?  The per-halfword swap akin to mips wsbh? 
 Yes, that operation also appears in arm (rev16) and ppc (brh).  So it's a reasonable 
thing to do.


r~