/usr/include/asm-x86_64 magic

Dear anybody!

The asm-x86_64/ includes at older systems located at linux-kerenel-source package.
Later moved to linux-glibc-devel package.
And later the asm-x86_64/ removed from linux-glibc-devel package. This mean yet missing.

:\ In the old systems the asm-i386/ contained 32 bit headers the asm-x86_64/ contained 64 bit headers. This changes mean the asm-x86/ now contain64 bit headers in case of 64 bit distribution?

Thanks for any information.