Re: [PATCH v6 00/20] target/arm: Reduce overhead of cpu_get_tb_cpu_state

[Peter Maydell]

On Fri, 11 Oct 2019 at 16:55, Richard Henderson
<address@hidden> wrote:
> Richard Henderson (20):
>   target/arm: Split out rebuild_hflags_common
>   target/arm: Split out rebuild_hflags_a64
>   target/arm: Split out rebuild_hflags_common_32
>   target/arm: Split arm_cpu_data_is_big_endian
>   target/arm: Split out rebuild_hflags_m32
>   target/arm: Reduce tests vs M-profile in cpu_get_tb_cpu_state
>   target/arm: Split out rebuild_hflags_a32
>   target/arm: Split out rebuild_hflags_aprofile
>   target/arm: Hoist XSCALE_CPAR, VECLEN, VECSTRIDE in
>     cpu_get_tb_cpu_state
>   target/arm: Simplify set of PSTATE_SS in cpu_get_tb_cpu_state
>   target/arm: Hoist computation of TBFLAG_A32.VFPEN
>   target/arm: Add arm_rebuild_hflags
>   target/arm: Split out arm_mmu_idx_el
>   target/arm: Hoist store to cs_base in cpu_get_tb_cpu_state
>   target/arm: Add HELPER(rebuild_hflags_{a32,a64,m32})
>   target/arm: Rebuild hflags at EL changes
>   target/arm: Rebuild hflags at MSR writes
>   target/arm: Rebuild hflags at CPSR writes
>   target/arm: Rebuild hflags for M-profile.
>   target/arm: Rely on hflags correct in cpu_get_tb_cpu_state

Don't we also need to do something to rebuild the hflags
for M-profile writes to the memory mapped system registers?
For instance rebuild_hflags_m32() bakes in state which
cares about env->v7m.ccr, which is set via nvic_writel(),
but I don't see anything whereby the write to the NVIC
register triggers a rebuild of the hflags value. Maybe I
missed it?

thanks
-- PMM