[PATCH] Emit a trap instruction for IR 'unreachable'

[Vadim Chugunov]

  I would at least write it as:


    ; CHECK-NEXT: ud2
    ; CHECK-NEXT: %bb8.i329


  to preserve the original intent of the test as well.

  Also, I would expect to see ud2 only on x64 windows, not for other x64 OS'es.   Hmm... Perhaps it would be better to change this test to use non-Windows target triple, and write another one that specifically checks 'unreachable' -> 'ud2' transform on x64 Windows?

http://reviews.llvm.org/D3417