[PATCH] [COMPILER-RT] Implement long double comparison functions

[GuanHong Liu]

  We assume sizeof(long double)=16 (IEEE-754 128-bit format)
  __SIZEOF_LONG_DOUBLE__=8 in SPARC and __SIZEOF_LONG_DOUBLE__=16 in SPARC64
  __SIZEOF_INT128__ =16 is also defined in SPARC64, so these funcitons can be compiled in SPARC64

  Could you specify the situation about when the problem occurs? Thanks

http://llvm-reviews.chandlerc.com/D2797