[Bug target/81616] Update -mtune=generic for the current Intel and AMD processors

[andrewm.roberts at sky dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81616

--- Comment #20 from Andrew Roberts <andrewm.roberts at sky dot com> ---
Again those latest mt19937ar results above were with the current snapshot:

/usr/local/gcc/bin/gcc -v
Using built-in specs.
COLLECT_GCC=/usr/local/gcc/bin/gcc
COLLECT_LTO_WRAPPER=/usr/local/gcc-8.0.0/libexec/gcc/x86_64-unknown-linux-gnu/8.0.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-8.0.0/configure --prefix=/usr/local/gcc-8.0.0
--program-suffix= --disable-werror --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-gnu-unique-object
--enable-linker-build-id --with-linker-hash-style=gnu --enable-plugin
--enable-initfini-array --enable-gnu-indirect-function --with-isl
--enable-languages=c,c++,fortran,lto --disable-libgcj --enable-lto
--enable-multilib --with-tune=generic --with-arch_32=i686
--host=x86_64-unknown-linux-gnu --build=x86_64-unknown-linux-gnu
--disable-bootstrap
Thread model: posix
gcc version 8.0.0 20171126 (experimental) (GCC)