aarch64: -mcpu= passes -mcpu= instead of -march= to as with -no-integrated-as unlike GCC

[pinskia]

GCC was changed this behavior almost 10 years ago: https://gcc.gnu.org/pipermail/gcc-patches/2015-August/426507.html .

The reason is because GNU binutils and GCC are seperate projects so an older binutils can be used with a newer GCC without any issues. Plus it allows for GCC to use a different assembler besides GNU binutils which might not have that specific -mcpu option.

clang should do the same.

Right now -no-integrated-as -mcpu=oryon-1 is broken when using with clang and GNU binutils' as because of this . oryon-1 was not added to GNU binutils because it was not needed for when use with GCC; in fact there are other most other -mcpu= options have not been added to GNU binutils for this same reason.

[llvmbot]

@llvm/issue-subscribers-clang-driver

Author: Andrew Pinski (pinskia)

GCC was changed this behavior almost 10 years ago: https://gcc.gnu.org/pipermail/gcc-patches/2015-August/426507.html .

The reason is because GNU binutils and GCC are seperate projects so an older binutils can be used with a newer GCC without any issues. Plus it allows for GCC to use a different assembler besides GNU binutils which might not have that specific -mcpu option.

clang should do the same.

Right now -no-integrated-as -mcpu=oryon-1 is broken when using with clang and GNU binutils' as because of this . oryon-1 was not added to GNU binutils because it was not needed for when use with GCC; in fact there are other most other -mcpu= options have not been added to GNU binutils for this same reason.