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[RegisterCoalescer] Improve handling of COPY instructions with identical value numbers
AbandonedPublic

Authored by tpr on Jun 22 2018, 4:57 AM.

Details

Reviewers
kparzysz
MatzeB
Summary

This subsumes Krzysztof's D48102, which itself was an alternative to D48032.

It does not include Krzysztof's 'Fix the "cannot join subranges" issue
caused by redefining an undef value' part of D48102, on the basis that
there is a different fix for that on D35073 that we need to refine and
upstream.

Change-Id: I73363db649916046eff58854c957d41a06157b3b

Diff Detail

Event Timeline

tpr created this revision.Jun 22 2018, 4:57 AM

I don't want to be spending time reviewing more alternatives at this point. I'm familiar with what I've started and I fixed all known problems. I still need to analyze the problems in detail either way and reviewing additional patches is just more work for me.

lib/CodeGen/RegisterCoalescer.cpp
1647

I have fixed this differently in the previous review.

2830

This is an overkill.

tpr abandoned this revision.Jun 22 2018, 4:39 PM

OK, I'll kill this one.