Re: [PATCH 3/4] target/arm: Take an exception if PC is misaligned

[Richard Henderson]

On 8/19/21 6:50 AM, Richard Henderson wrote:
> On 8/19/21 3:40 AM, Peter Maydell wrote:
> > >       uint32_t insn;
> > >       bool is_16bit;
> > >
> > > -    if (arm_pre_translate_insn(dc)) {
> > > +    if (arm_check_ss_active(dc) || arm_check_kernelpage(dc)) {
> >
> >
> > Is it not possible to get a misaligned PC in the Thumb case ?
>
> No.  The thumb bit is always removed, leaving all pc aligned mod 2.
> Both BXWritePC and BranchWritePC do this, as do we in gen_bx and store_reg.

Do you think it's worth an assert here to make sure we never miss a case?  I did an audit 
of the exception code and it looks like we mask everything correctly there, but...


r~