[cfe-commits] NEON vector alignment
bob.wilson at apple.com
Mon Apr 4 14:18:04 PDT 2011
On Apr 4, 2011, at 2:12 PM, Sandeep Patel wrote:
> On Mon, Apr 4, 2011 at 4:58 PM, Bob Wilson <bob.wilson at apple.com> wrote:
>> On Mar 31, 2011, at 2:06 PM, Sandeep Patel wrote:
>>> Clang aligns NEON vectors differently than llvm-gcc does.
>>> llvm-gcc actually calls into ARMTargetMachine to get the layout, but
>>> Clang provides it's own definitions.
>>> llvm-gcc's definition appears to be correct, so this changes Clang to that.
>> Thanks, Sandeep. While reviewing your patch, I noticed that further changes were needed for the APCS ABI, so I went ahead and made those changes as well. Committed as svn r128825.
> Now that you made me look at the parts beyond v128 :-), I'm doubting
> the AACPS values for i1,i8, and i16.
> The layouts in ARMTargetMachine.cpp for ARM don't have these smaller
> integer types listed at all. Should they be explicit?
I think it's OK. The ThumbTargetMachine versions have the small integer types listed explicitly because they increase the preferred alignment. I assume there's a good reason for that, but I don't know what it is.
For ARM mode, Clang is just setting the default values for those types.
More information about the cfe-commits