[Thumbv8] Fix the value of BLXOperandIndex of isV8EligibleForIT

Originally, BLX was passed as operand #0 in MachineInstr and as operand
#2 in MCInst. But now, it's operand #2 in both cases.

This patch also removes unnecessary FileCheck in the test case added by r199127.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199928 91177308-0d34-0410-b5e6-96231b3b80d8
Replace the interim lli build fix with something cleaner

Eliminates the LLI_BUILDING_CHILD build hack from r199885.

Also add a FIXME to remove code that tricks the tests into passing when the
feature fails to work. Please don't do stuff like this, the tests exist for a
reason!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199929 91177308-0d34-0410-b5e6-96231b3b80d8
Remove unused include following r199929

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199930 91177308-0d34-0410-b5e6-96231b3b80d8
Note the PR number.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199932 91177308-0d34-0410-b5e6-96231b3b80d8
Replace vfmaddxx213 instructions with their 231-type equivalents in accumulator
loops. Writing back to the accumulator (231-type) allows the coalescer to
eliminate an extra copy.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199933 91177308-0d34-0410-b5e6-96231b3b80d8
Updating the getting started guide for Visual Studio a smidge.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199934 91177308-0d34-0410-b5e6-96231b3b80d8