On Mon, 17 Aug 2026 at 17:37, Peter Maydell <[email protected]> wrote: > > On Tue, 11 Aug 2026 at 20:16, Richard Henderson > <[email protected]> wrote: > > > > The trans_WHILE_ptr function incorrectly handles the case where the > > address difference divided by ESIZE results in zero. This happens when > > the address difference is less than ESIZE but greater than zero. > > > > Fix by dropping direct comparisons of op0 vs op1, and instead > > testing the scaled diff vs 0. Merge with the bounding to the > > maximum vector length via wrapping arithmetic. > > > > Reported-by: YanjunYang <[email protected]> > > Signed-off-by: Richard Henderson <[email protected]> > > --- > > target/arm/tcg/translate-sve.c | 38 +++++++++++++++++++++------------- > > 1 file changed, 24 insertions(+), 14 deletions(-) > > > > - /* Since we're bounded, pass as a 32-bit type. */ > > + /* > > + * If diff == 0, the condition is always true. Also, bound to max. > > + * Simplify > > + * diff = diff ? diff : max; > > + * diff = umin(diff, max); > > + * via > > + * diff -= 1; > > + * diff = umin(diff, max - 1); > > + * diff += 1; > > + * via 0 - 1 == UINT64_MAX. > > + */ > > + tcg_gen_addi_i64(diff, diff, -1); > > + tcg_gen_umin_i64(diff, diff, tcg_constant_i64((vsz >> a->esz) - 1)); > > + > > + /* > > + * Since we're bounded, pass as a 32-bit type. > > + * Sink the diff += 1 from above into the 32-bit type. > > Is it worth doing that? Hosts are all 64-bits now, and surely there's > not going to be a perf or codesize difference between "add 1" > on a 32-bit type vs a 64-bit type ?
Other than that Reviewed-by: Peter Maydell <[email protected]> thanks -- PMM
