Compiler-explorer: [BUG] ARM assembly code is directed to x86 opcode documentation

[VivekChugh]

linking opcode document with assembly code is very helpful feature.
But even ARM assembly code is also directed to x86 opcode documentation.

[FlashSheridan]

Also RISC-V; both it and ARM are particularly confusing with the default example, int square(int num), since the one significant operation is mul, which is glossed by the popup text as “unsigned multiplication” — without a warning that the documentation is only for x86, and that for the other two, mul is not necessarily unsigned. (The context menu _does_ note that it’s x86; as an interim mitigation, I’d suggest a similar note in the popup text.)

[mattgodbolt]

Thanks both. The fact that it's not clearly labeled as x86_64 is misleading I agree. Will see if we can minimally do something about that!

[mattgodbolt]

https://developer.arm.com/architectures/cpu-architecture/a-profile/exploration-tools might be handy here