[PATCH] D28759: [ExecutionDepsFix] Improve clearance calculation for loops

[Marina Yatsina via Phabricator via llvm-commits]

myatsina accepted this revision.
myatsina added a comment.
This revision is now accepted and ready to land.

Added a few minor comments.

LGTM once they are addressed.



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Comment at: lib/CodeGen/ExecutionDepsFix.cpp:415
+    LiveReg *Incoming = fi->second.OutRegs;
+    if (Incoming == nullptr) {
       continue;
----------------
loladiro wrote:
> myatsina wrote:
> > Is OutRegs null when it's a back edge from a BB we haven't seen yet? Are there other cases where it can be null?
> > Please add a comment explaining the cases.
> Yes, that's correct. If it's null it's a back edge. Will add a comment to this extent.
Don't forget to add the comment :)


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Comment at: test/CodeGen/X86/break-false-dep.ll:313
+  %nextj = add i64 %phi_j, 1
+  ; Register use, plus us clobbering 7-15 above, basically forces xmm7 here as
+  ; the only reasonable choice. The primary thing we care about is that it's
----------------
xmm7 --> xmm6 ?


https://reviews.llvm.org/D28759