SPECTRE attacks mitigations were added to SpiderMonkey's JIT output in
version 57. Turning these off is a very large speedup, around 10-20%
wall time (on my computer) depending on the map and the situation.
For the most part, from profiling on my machine, this is from memory
fences after JIT -> C++ calls. 0 A.D. does a lot of these.
The SPECTRE class of attack is a timing attack based on speculative
execution to leak sensitive information, and it seems extraordinarily
unlikely that something like this could be successfully mounted using 0
A.D.
Differential Revision: https://code.wildfiregames.com/D5014
This was SVN commit r27699.
wraitii
61e932a890