[kmeisthax]

x86 and ARM both have options for executing certain instructions with data-independent timing. The problem here is that languages and compilers need to expose and honor data types that compile down to only those instructions.

This would be something like a 'secret' keyword that would qualify integer types; i.e. in C you could have a variable of type 'secret unsigned int' and the compiler would reject optimizations that would reveal timing information about the variable's contents, while optimizing the rest of the program's non-secret variables. Values can be promoted to secret but not demoted. Code that intends to reveal secrets (e.g. to write them out to secure storage) must explicitly cast away the secretness.

AFAIK Golang has crypto/subtle, but that's more special functions to do certain things in a data-independent way and not pervasive language support for it (and, presumably, they have to keep updating the compiler to not optimize that specific module).