* enable notdirty_write for snapshots when possible
Snapshots only happens when the priority of the memory region is smaller
then the snapshot_level. After a snapshot notdirty can be set.
* disable notdirty_write for self modifying code
When SMC access the memory region more then once the
tb must be rebuild multible times.
fixes#2029
* notdirty_write better hook check
Check all relevant memory hooks before enabling notdirty write.
This also checks if the memory hook is registered for the affected
region. So it is possible to use notdirty write and have some hooks
on different addresses.
* notdirty_write check for addr_write in snapshot case
* self modifying code clear recursive mem access
when self modifying code does unaligned memory accese sometimes
uc->size_recur_mem is changed but for notdirty write not changed back.
This causes mem_hooks to be missed. To fix this uc->size_recur_mem is
set to 0 before each cpu_exec() call.
Every store would always cause the tb_invalidate_phys_page_fast path to be invoked,
amounting to a 40x slowdown of stores compared to loads.
Change this code to only worry about TB invalidation for regions marked as
executable (i.e. emulated executable).
Even without uc_set_native_thunks, this change fixes most of the performance
issues seen with thunking to native calls.
Signed-off-by: Andrei Warkentin <andrei.warkentin@intel.com>
We still need this API because the virtual memory address space of
32 bits os is only 4GB and we default need 1G per instance
Credits to @ZehMatt for original idea
Co-authored-by: ζeh Matt <5415177+ZehMatt@users.noreply.github.com>
