[ptx] More test tweaks

[Nathan Sidwell]

This adjusts a few more tests:
* I'd missed the optimization glob on a ptx skip-if, so it wasn't being skipped.
* An asm test relied on the register allocator being run to assign an input to 
the same register  as an output.
* An atomic test operated on automatic storage, which doesn't work on ptx -- 
atomic operations are only valid for global or shared memory.  Allocating it to 
static storage allows it to pass.
* PTX doesn't stick to the IEEE rules for one or more of denorms, zero or nan 
signedness.

nathan
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ptx-tests.patch
Type: text/x-patch
Size: 2239 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20160517/71ee5a54/attachment.bin>