Re: [PATCH 3/3] arm: smh: Allow semihosting trap calls to be inlined

On Wed, Oct 05, 2022 at 05:38:49PM +0100, Andre Przywara wrote:

Currently our semihosting trap function is somewhat fragile: we rely on the current compiler behaviour to assign the second inline assembly argument to the next free register (r1/x1), which happens to be the "addr" argument to the smh_trap() function (per the calling convention). I guess this is also the reason for the noinline attribute.

Make it explicit what we want: the "addr" argument needs to go into r1, so we add another register variable. This allows to drop the "noinline" attribute, so now the compiler beautifully inlines just the trap instruction directly into the calling function.

Signed-off-by: Andre Przywara andre.przywara@arm.com

Applied to u-boot/master, thanks!