Are there good libraries for doing runtime feature detection? Eg, include three versions of hot function X in the binary, and have it seamlessly insert the correct function pointer at startup? Or have the function contain multiple bodies and just JMP to the correct block of code?
I know you can do this yourself, but last time I looked it was a heavily manual process— you had to basically define a plugin interface and dynamically load your selected implementation from a separate shared object. What are the barriers to having compilers able to be hinted into transparently generating multiple versions of key functions?
I know you can do this yourself, but last time I looked it was a heavily manual process— you had to basically define a plugin interface and dynamically load your selected implementation from a separate shared object. What are the barriers to having compilers able to be hinted into transparently generating multiple versions of key functions?