[llvm] [RISCV][MCP] Remove redundant move from tail duplication (PR #89865)

[Craig Topper via llvm-commits]

https://github.com/topperc commented:

Removing CopyOperands.Source->isRenamable() from isBackwardPropagatableCopy is another way to fix this without changing copyPhysReg. propagateDefs checks the renamable flag on the def it is propagating into. So the check in isBackwardPropagatableCopy might not be functionally needed.

https://github.com/llvm/llvm-project/pull/89865