17 May
2020
17 May
'20
2:35 a.m.
Paul Winalski <paul.winalski(a)gmail.com> writes:
On 5/15/20, Warner Losh <imp(a)bsdimp.com> wrote:
My understanding is that it is a lot more efficient to use unsigned char
on arm. You can make gcc, for example, deal with this, but it costs. I
remember having to tell gcc to deal with it when I ported the Doom
engine to a StrongARM processor device under NetBSD many years ago. I
mostly remember the code running well enough, but it was larger.
--
Brad Spencer - brad(a)anduin.eldar.org - KC8VKS - http://anduin.eldar.org
arm has been the biggest outlier in terms of unsigned char. In FreeBSD,
this has been the second largest source of bugs with the platform... the
OABI weird alignment requirements being the first (thankfully behind us)...
Why did the implementers of the Unix ABI for ARM decide to have char
be unsigned? Was there an architectural reason for it?
-Paul W.