The previous code had a few problems, motivating the choices here.
1. It could create instructions clobbering CPSR, but the incoming MachineInstr
didn't reflect this. A potential source of corruption. This is why the patch
has a new PseudoInst for before lowering.
2. Similarly, there was some code to handle the incoming instruction not being
ARMCC::AL, but this would have caused massive problems if it was actually
invoked when a complex offset needing more than one instruction was requested.
3. It wasn't designed to handle unaligned pointers (or offsets). These should
probably be minimised anyway, but the code needs to deal with them properly
regardless.
4. It had some rather dubious ad-hoc code to avoid calling
emitThumbRegPlusImmediate, a function which should be designed to do precisely
this job.
We seem to cover the common cases correctly now, and hopefully can enhance
emitThumbRegPlusImmediate to handle any extra optimisations we need to add in
future.
llvm-svn: 220236
This was done with the following sed invocation to catch label lines demarking function boundaries:
sed -i '' "s/^;\( *\)\([A-Z0-9_]*\):\( *\)test\([A-Za-z0-9_-]*\):\( *\)$/;\1\2-LABEL:\3test\4:\5/g" test/CodeGen/*/*.ll
which was written conservatively to avoid false positives rather than false negatives. I scanned through all the changes and everything looks correct.
llvm-svn: 186258
Tim Northover