[llvm] [MachineCopyPropagation] Recognise and delete no-op moves produced after forwarded uses (PR #129889)

[Craig Topper via llvm-commits]

topperc wrote:

@steven-michaud I wonder if adding `MI.getNumImplicitOperands() == 0` to the checks before deleting the instruction would fix the issue. Hopefully, if the upper bits are used there will be an implicit definition operand of the 64-bit register. There was similar fix in e4b4a939f8852b2d5aab0d5b999890c7ef85be18.

https://github.com/llvm/llvm-project/pull/129889