Fixing stale code tlb after fetch-prot hook

[bwhitn]

Fixes a stale code TLB path after a handled UC_HOOK_MEM_FETCH_PROT callback.

When a fetch-protection callback returns true, Unicorn treats the access as handled and continues translation. The read/write protected paths already reload TLB state after a handled callback, but the fetch-protection path did not. If the callback changes permissions, for example:

uc_mem_protect(uc, page, size, UC_PROT_ALL);
return true;

the translator can continue using stale fetch TLB state.

This patch re-checks that the page is still mapped and now executable after a handled fetch-protection callback, then refills the code TLB entry before instruction bytes are read.

I believe this fixes #1780 and is related to #1393.

Added regression test.

[PhilippTakacs]

nice catch. I haven't run the test yet, but in general it looks good.

Can you change the target branche to dev?

[bwhitn]

Done

[PhilippTakacs]

Can you also rebase your branch to dev and remove the 3 unrelated commits? If you have problems you can also just create a new PR and cherry-pick your commit.

[bwhitn]

Sorry about that, I think it is good now.

[PhilippTakacs]

LGTM

[wtdcode]

Looks good.