[pieterbreed]

Is this for the runtime of the compiled code or for the compiling machine? Do they generate slow code if the compiler is running on non-intel?

[Uvix]

Runtime of the compiled code. The ostensible intent is so that new processors can use new features like SIMD, while offering a fallback for older ones. In practice, they’re detecting an Intel processor, not just the specific feature.

[kstrauser]

For the compiled code. Its output deliberately runs slower on non-Intel CPUs.

[SSLy]

the runtime. patching cpuid makes the code go faster