Re: powerpc/Makefile: set -mcpu=860 flag for the 8xx

From: Michael Ellerman
Date: Mon Jun 04 2018 - 10:11:21 EST


On Mon, 2018-05-28 at 06:08:34 UTC, Christophe Leroy wrote:
> When compiled with GCC 8.1, vmlinux is significantly bigger than
> with GCC 4.8.
>
> When looking at the generated code with objdump, we notice that
> all functions and loops when a 16 bytes alignment. This significantly
> increases the size of the kernel. It is pointless and even
> counterproductive as on the 8xx 'nop' also consumes one clock cycle.
>
> Size of vmlinux with GCC 4.8:
> text data bss dec hex filename
> 5801948 1626076 457796 7885820 7853fc vmlinux
>
> Size of vmlinux with GCC 8.1:
> text data bss dec hex filename
> 6764592 1630652 456476 8851720 871108 vmlinux
>
> Size of vmlinux with GCC 8.1 and this patch:
> text data bss dec hex filename
> 6331544 1631756 456476 8419776 8079c0 vmlinux
>
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/1c38976334c0efce1b285369a6037f

cheers