[PATCH, middle end]: Fix PR 37908, thinko with atomic NAND operation

[Jakub Jelinek]

On Fri, Oct 24, 2008 at 12:18:41PM +0200, Uros Bizjak wrote:
> Currently, we are expanding atomic NAND operation as "target =
> (~target & val)", whic is simply not NAND operation. Correct operation
> would be "target = ~(target & val)".

1) you have attached a different test.
2) I think the __sync*nand* builtins do what is documented:

...
`TYPE __sync_fetch_and_nand (TYPE *ptr, TYPE value, ...)'
     These builtins perform the operation suggested by the name, and
     returns the value that had previously been in memory.  That is,

          { tmp = *ptr; *ptr OP= value; return tmp; }
          { tmp = *ptr; *ptr = ~tmp & value; return tmp; }   // nand

...
`TYPE __sync_nand_and_fetch (TYPE *ptr, TYPE value, ...)'
     These builtins perform the operation suggested by the name, and
     return the new value.  That is,

          { *ptr OP= value; return *ptr; }
          { *ptr = ~*ptr & value; return *ptr; }   // nand

So I'd say the submitter just haven't read the documentation.

	Jakub