Re: e500 core lacks lswi, lswx, stswi, and stswx instructions.

Matt Thomas <[email protected]> Tue, 20 Jan 2015 10:17:19 -0800
Newsgroups gmane.os.netbsd.ports.powerpc
Message-ID <[email protected]>
> On Jan 20, 2015, at 10:15 AM, matthew green <[email protected]> wrote:
> 
> 
> BTW, the reason i care is that i use -Os on the G4.  it gives me
> a minor speedups for my kernel.  but this will remove some part
> of that speedup in both useful instructions and code size, unless
> i'm totally misunderstanding what this does to code gen.

That savings is from -mmultiple not from -mstring.  That causes the
function prologue/epilogue to shrink a lot thereby making the icache
more effective.