[PATCH] D17350: [AArch64][ShrinkWrap] Fix bug in prolog clobbering live reg when shrink wrapping.

[Tim Northover via llvm-commits]

t.p.northover added a comment.

Hi Geoff,

I'm not sure this is going to work. I think this sequence of events might break:

1. During shrink-wrapping, canUseAsPrologue finds a callee-saved register and decides the block can be used.
2. PrologueEpilogueInserter adds all callee-saved registers as live-ins to the candidate shrink-wrapped prologue and calls emitPrologue.
3. emitPrologue asks for a callee-saved register again and is told there aren't any.

Tim.


http://reviews.llvm.org/D17350