Convert a llc -filetype=obj test into a llvm-mc test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193534 91177308-0d34-0410-b5e6-96231b3b80d8
Return early from getUnconditionalBranchTargetOpValue if the branch target is
an MCExpr, in order to avoid writing an encoded zero value in the immediate
field.

When getUnconditionalBranchTargetOpValue is called with an MCExpr target, we
don't know what the final immediate field value should be. We shouldn't
explicitly set the immediate field to an encoded zero value as zero is encoded
with a non-zero bit pattern. This leads to bits being set that pollute the
final immediate value. The nature of the encoding is such that the polluted
bits only affect very large immediate values, explaining why this hasn't
caused problems earlier.

Fixes <rdar://problem/15155975>.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193535 91177308-0d34-0410-b5e6-96231b3b80d8
Convert another llc -filetype=obj test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193536 91177308-0d34-0410-b5e6-96231b3b80d8