Gnu Assembler compatibility fails on ldrd r12, [...]

[kaomoneus]

Bugzilla Link	19320
Resolution	FIXED
Resolved on	Apr 14, 2014 02:32
Version	trunk
OS	All
Blocks	#19300
Attachments	Test case
CC	@compnerd,@rengolin

Extended Description

GNU Assembler compatibility fails on several commands:
ldrd r12, [r0, #​32]
strd r12, [r0, #​32]

The trouble as in ARMAsmParser, in ParseInstruction method. It assumes that ARM::R12 + 1 == ARM::SP.
It is wrong, since ARM:: codes are generated by tablegen and actually could be any random numbers.

I think its critical misbehaviour. So first fast fix patch will be sent to LLVM-Commits.
While actually I would like get rid of

// GNU Assembler extension (compatibility)
...

in further commits.

[kaomoneus]

What do you think guys about get-rid of workaround in ParseInstruction?

[rengolin]

Hi Stepan,

I think you better send a patch about the area in ParseInstruction and what do you intend to do, so we can have a better opinion. But generally, if the parser is assuming R12+1=SP, I'd say that's a bug that needs to be fixed independently of the GNU compatibility issue.

[kaomoneus]

Hi Renato,
I have sent my first diff to llvm-reviews:
http://llvm-reviews.chandlerc.com/D3273

I'm not sure whether everything I did fine with phabricator, it my very first experience.
It's also odd it published all my internal log file :-) Is it possible to disable it?

[rengolin]

What I normally do using git is to:

$ git diff -U999 master > my.patch

and upload that patch to Phab.

The history won't be there and the -U helps with the context.

[kaomoneus]

Fixed in r205524.