Yes, you are correct.
My idea is to cause a compile error if the backend can't use all instructions for which it knows the worst case latency or if it can't use purely constant-time instructions.
My idea is to cause a compile error if the backend can't use all instructions for which it knows the worst case latency or if it can't use purely constant-time instructions.
In the crypto example, the backend would have to be sophisticated enough to know when the same addresses would be accessed every time, like bitslicing in AES. [1]
The devil absolutely is in the details. This is why I say Yao's capabilities on this front are unproven.
[1]: https://www.bearssl.org/constanttime.html#constant-time-in-b...