Not a direct answer, but the following snippet from the linked page gives the key (emphasis mine):
Not all operations are supported by all target processors. If a specific operation cannot be implemented on the target processor, a warning will be generated and an external function will be called . The external function will have the same name as the built-in function, with the additional suffix `_n ', where n is the size of the data type.
Basically, this suggests that it is safe to use these built-in functions. They will generate either a direct sequence of commands, if supported, or a call to the emulation function by a given name.
The compiler will warn you if a specific built-in function is not supported, so it is easy to experiment.
And since they were originally taken from Intel specifications, we can safely assume that they are on x86 and x86_64.
Nikolai Fetissov
source share