Re: [RFC PATCH 27/34] accel/tcg: Make translate-all.c target independent

[Richard Henderson]

On 6/13/24 02:50, Anton Johansson wrote:
> On 24/01/24, Richard Henderson wrote:
> > On 1/20/24 00:40, Anton Johansson wrote:
> > > Makes translate-all.c independent of softmmu target by switching
> > >
> > >       TARGET_LONG_BITS        -> target_long_bits()
> > >
> > >       TARGET_INSN_START_WORDS -> tcg_ctx->insn_start_words,
> > >                                  target_insn_start_words(),
> > >
> > >       TCG_GUEST_DEFAULT_MO    -> target_default_memory_order()
> > >
> > >       MO_TE                   -> target_endian_memory_order()
> > >
> > > Signed-off-by: Anton Johansson <anjo@rev.ng>
> > > ---
> > >    accel/tcg/translate-all.c | 38 ++++++++++++++++++--------------------
> > >    1 file changed, 18 insertions(+), 20 deletions(-)
> > >
> > > diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
> > > index 9c981d1750..a3ae0c6910 100644
> > > --- a/accel/tcg/translate-all.c
> > > +++ b/accel/tcg/translate-all.c
> > > @@ -65,7 +65,6 @@
> > >    #include "internal-common.h"
> > >    #include "internal-target.h"
> > >    #include "perf.h"
> > > -#include "tcg/insn-start-words.h"
> > >    TBContext tb_ctx;
> > > @@ -106,7 +105,7 @@ static int64_t decode_sleb128(const uint8_t **pp)
> > >            val |= (int64_t)(byte & 0x7f) << shift;
> > >            shift += 7;
> > >        } while (byte & 0x80);
> > > -    if (shift < TARGET_LONG_BITS && (byte & 0x40)) {
> > > +    if (shift < target_long_bits() && (byte & 0x40)) {
> >
> > You just make TARGET_PAGE_SIZE etc target independent, right?
> > So you don't need this?  Or is this because of user-only still.
>
> Hi, Richard!
>
> I missed this piece of feedback previously.  I don't see how
> TARGET_PAGE_[SIZE|BITS] would be used here.  Are the values we're
> encoding always TARGET_PAGE_BITS in size?

I was obviously tired here, since they're obviously unrelated.

However in this case I think TARGET_LONG_BITS is a red herring, and we should be using 
int64_t not target_long at all, and thus the shift count must be less than 64.


r~