This converts the ARM AsmParser to use the new assembly matcher error
reporting mechanism, which allows errors to be reported for multiple
instruction encodings when it is ambiguous which one the user intended
to use.
By itself this doesn't improve many error messages, because we don't have
diagnostic text for most operand types, but as we add that then this will allow
more of those diagnostic strings to be used when they are relevant.
Differential revision: https://reviews.llvm.org/D31530
llvm-svn: 314779
Immediate branch targets aren't commonly used, but if they are we should make
sure they can actually be encoded. This means they must be divisible by 2 when
targeting Thumb mode, and by 4 when targeting ARM mode.
Also do a little naming cleanup while I was changing everything around anyway.
llvm-svn: 275116