Thumb one requires that many arithmetic instruction forms have an 'S'
suffix. For Thumb2, the whether the suffix is required or precluded depends
on whether the instruction is in an IT block. Use target parser predicates
to check for these sorts of context-sensitive constraints.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137746 91177308-0d34-0410-b5e6-96231b3b80d8
and MCSubtargetInfo.
- Added methods to update subtarget features (used when targets automatically
detect subtarget features or switch modes).
- Teach X86Subtarget to update MCSubtargetInfo features bits since the
MCSubtargetInfo layer can be shared with other modules.
- These fixes .code 16 / .code 32 support since mode switch is updated in
MCSubtargetInfo so MC code emitter can do the right thing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134884 91177308-0d34-0410-b5e6-96231b3b80d8
