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Summary

  1. [MachineCopyPropagation] Remove redundant copies after TailDup via (details)
Commit 9115c477bb6e1b686f12941d150e992649646321 by lkail
[MachineCopyPropagation] Remove redundant copies after TailDup via
machine-cp
Summary: After tailduplication, we have redundant copies. We can remove
these copies in machine-cp if it's safe to, i.e.
```
$reg0 = OP ...
... <<< No read or clobber of $reg0 and $reg1
$reg1 = COPY $reg0 <<< $reg0 is killed
...
<RET>
``` will be transformed to
```
$reg1 = OP ...
...
<RET>
```
Differential Revision: https://reviews.llvm.org/D65267
llvm-svn: 371359
The file was modifiedllvm/test/CodeGen/X86/umulo-128-legalisation-lowering.ll
The file was modifiedllvm/test/CodeGen/X86/mul-i512.ll
The file was modifiedllvm/lib/CodeGen/MachineCopyPropagation.cpp
The file was modifiedllvm/test/CodeGen/PowerPC/redundant-copy-after-tail-dup.ll