Hi Richard,
Thanks for the comment.
> -----Original Message-----
> From: Richard Henderson <richard.hender...@linaro.org>
> Sent: 11 December 2024 22:50
> To: Konrad, Frederic <frederic.kon...@amd.com>; qemu-ri...@nongnu.org
> Cc: pal...@dabbelt.com; alistair.fran...@wdc.com; bmeng...@gmail.com;
> liwei1...@gmail.com;
> dbarb...@ventanamicro.com; zhiwei_...@linux.alibaba.com;
> qemu-devel@nongnu.org; Iglesias, Francisco
> <francisco.igles...@amd.com>; Michel, Luc <luc.mic...@amd.com>
> Subject: Re: [PATCH 2/3] target/riscv: generate misaligned access trap for
> rvi insn
>
> On 12/11/24 15:19, Frederic Konrad wrote:
> > Now there is an option to enable misaligned accesses traps, check the
> > alignment
> > during load and store for the RVI instructions. Do not generate them if the
> > zama16b extension is there.
> >
> > Signed-off-by: Frederic Konrad <fkon...@amd.com>
> > ---
> > target/riscv/insn_trans/trans_rvi.c.inc | 7 +++++++
> > 1 file changed, 7 insertions(+)
> >
> > diff --git a/target/riscv/insn_trans/trans_rvi.c.inc
> > b/target/riscv/insn_trans/trans_rvi.c.inc
> > index 96c218a9d7..1283207fc7 100644
> > --- a/target/riscv/insn_trans/trans_rvi.c.inc
> > +++ b/target/riscv/insn_trans/trans_rvi.c.inc
> > @@ -323,6 +323,10 @@ static bool gen_load(DisasContext *ctx, arg_lb *a,
> > MemOp memop)
> > {
> > bool out;
> >
> > + if (ctx->cfg_ptr->trap_misaligned_access &&
> > !ctx->cfg_ptr->ext_zama16b) {
> > + memop |= MO_ALIGN;
> > + }
> > +
> > if (ctx->cfg_ptr->ext_zama16b) {
> > memop |= MO_ATOM_WITHIN16;
> > }
> > @@ -424,6 +428,9 @@ static bool gen_store_i128(DisasContext *ctx, arg_sb
> > *a, MemOp memop)
> >
> > static bool gen_store(DisasContext *ctx, arg_sb *a, MemOp memop)
> > {
> > + if (ctx->cfg_ptr->trap_misaligned_access &&
> > !ctx->cfg_ptr->ext_zama16b) {
> > + memop |= MO_ALIGN;
> > + }
> > if (ctx->cfg_ptr->ext_zama16b) {
> > memop |= MO_ATOM_WITHIN16;
> > }
>
> I would imagine that ext_zama16b would disable or conflict with
> trap_misaligned_access at
> startup.
Ok I can fix that condition to:
if (ctx->cfg_ptr->trap_misaligned_access) {
And throw an error in the first patch if both are activated at the same time.
Best Regards,
Fred
>
>
> r~
