lkml.org 
[lkml]   [2015]   [Nov]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC/PATCH 0/3] ARM: Use udiv/sdiv for __aeabi_{u}idiv library functions
On Sun, Nov 22, 2015 at 08:25:27PM +0100, Arnd Bergmann wrote:
> The question is really about Marvell Dove, MMP and Armada 370,
> which are all based on PJ4 or PJ4B (CPU part : 0x581), so ARMv7-A
> and report idivt support but idiva.

Well, it's pretty hard to test when binutils blocks your ability to
write assembly using the instructions.

root@cubox:~# gcc -O2 -o idiv idiv.c -Wa,-mcpu='cortex-a9+idiv' -marm
/tmp/cc8WPQiB.s: Assembler messages:
/tmp/cc8WPQiB.s:32: Error: selected processor does not support ARM mode `udiv ip,r5,r4'
root@cubox:~# gcc -O2 -o idiv idiv.c -Wa,-mcpu='cortex-a9+idiv' -mthumb
/tmp/ccRzgAlM.s: Assembler messages:
/tmp/ccRzgAlM.s:36: Error: selected processor does not support Thumb mode `udiv r6,r5,r4'
root@cubox:~# gcc -O2 -o idiv idiv.c -Wa,-mcpu='marvell-pj4+idiv' -mthumb
/tmp/cc1JYyFD.s: Assembler messages:
/tmp/cc1JYyFD.s:36: Error: selected processor does not support Thumb mode `udiv r6,r5,r4'
root@cubox:~# gcc -O2 -o idiv idiv.c -Wa,-mcpu='marvell-pj4+idiv' -marm
/tmp/ccEQbQpp.s: Assembler messages:
/tmp/ccEQbQpp.s:32: Error: selected processor does not support ARM mode `udiv ip,r5,r4'

That's binutils 2.24 and gcc 4.8.4 as found on Ubuntu 14.04. I'm
sorry, but I don't have spare time to work out what the opcodes
would be.

--
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.


\
 
 \ /
  Last update: 2015-11-22 21:21    [W:1.229 / U:0.288 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site