code review 101740045: armasm: gnu syntax and objdump comparison test

armasm: gnu syntax and objdump comparison test

The test harnesses are adapted from the x86asm package.

[rsc, 2014-05-28 00:03:12]

Hello crawshaw,

I'd like you to review this change to
https://code.google.com/p/rsc.arm/

[rsc, 2014-05-28 18:35:01]

Hello minux.ma@gmail.com (cc: crawshaw@golang.org),

Please take another look.

[minux1, 2014-05-29 08:58:58]

I'm wondering why you don't just generate a binary
file containing the instructions and use this:
objdump -b binary -m arm -D --adjust-vma=0x8000 file
to get the disassembly (by changing -m option, this
also applies to 386 and amd64).

It's unfortunate that objdump refuses to take input
from stdin when it's a pipe. Though I understand
that we might want to retain the input file anyway.

PS: Using llvm-mc for this test is even easier it can
take input from a pipe. e.g.:
echo '0xD1 0x4C 0x55 0x2E' | \
  llvm-mc-3.4 -disassemble -triple=arm

I think it's even worthy to also check with llvm-mc
as I tried a few exceptions cases in the test and
objdump and llvm-mc disagree with each other.

[rsc, 2014-05-29 15:23:54]

On Thu, May 29, 2014 at 4:58 AM, <minux.ma@gmail.com> wrote:

> I'm wondering why you don't just generate a binary
> file containing the instructions and use this:
> objdump -b binary -m arm -D --adjust-vma=0x8000 file
> to get the disassembly (by changing -m option, this
> also applies to 386 and amd64).
>

I didn't know about all that magic when I wrote this code. For now I'd like
to leave it as is, although I might change it later.

PS: Using llvm-mc for this test is even easier it can
> take input from a pipe. e.g.:
> echo '0xD1 0x4C 0x55 0x2E' | \
>   llvm-mc-3.4 -disassemble -triple=arm
>

Nice. I'll add that in a future round. For now compatibility with objdump
is close enough. For the x86 I do compare objdump against Intel's xed.

Thanks.
Russ

[minux1, 2014-05-29 20:43:49]

LGTM.

[rsc, 2014-05-31 13:34:48]

*** Submitted as
https://code.google.com/p/rsc/source/detail?r=5daace81f8ee&repo=arm ***

armasm: gnu syntax and objdump comparison test

The test harnesses are adapted from the x86asm package.

LGTM=minux.ma
R=minux.ma
CC=crawshaw
https://codereview.appspot.com/101740045