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Date:   Mon, 28 Sep 2020 17:43:20 -0400 (EDT)
From:   Nicolas Pitre <nico@fluxnic.net>
To:     Rong Chen <rong.a.chen@intel.com>
cc:     kernel test robot <lkp@intel.com>, kbuild-all@lists.01.org,
        linux-kernel@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
        gcc@gcc.gnu.org
Subject: Re: {standard input}:1174: Error: inappropriate arguments for opcode
 'mpydu'
In-Reply-To: <783f6c8f-1ef4-f5f6-9ac2-b2372c7f340d@intel.com>
Message-ID: <nycvar.YSQ.7.78.906.2009281705410.1581@knanqh.ubzr>
References: <202008300726.ynqzYKmk%lkp@intel.com> <nycvar.YSQ.7.78.906.2008292257360.1479@knanqh.ubzr> <783f6c8f-1ef4-f5f6-9ac2-b2372c7f340d@intel.com>
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On Sun, 27 Sep 2020, Rong Chen wrote:

> Hi Nicolas,
> 
> Thanks for the feedback, the error still remains with gcc 10.2.0:

I've created the simplest test case that can be. You won't believe it.

Test case:

$ cat test.c
unsigned int test(unsigned int x, unsigned long long y)
{
	y /= 0x20000000;
	if (x > 1)
		y *= x;
	return y;
}
$ export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:~/0day/gcc-9.3.0-nolibc/arc-elf/libexec/gcc/arc-elf/9.3.0
$ ~/0day/gcc-9.3.0-nolibc/arc-elf/bin/arc-elf-gcc -mcpu=hs38 -mbig-endian -O2 -c test.c
/tmp/cc0GAomh.s: Assembler messages:
/tmp/cc0GAomh.s:21: Error: inappropriate arguments for opcode 'mpydu'

I know nothing about ARC. Please anyone take it over from here.


Nicolas