[PATCH] D110182: [LiveIntervals] Find better anchoring end points when repairing ranges

[Matthias Braun via Phabricator via llvm-commits]

MatzeB added a comment.

Change looks good to me, but I would apreciate a better test.



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Comment at: llvm/lib/CodeGen/LiveIntervals.cpp:1665-1670
   // Find anchor points, which are at the beginning/end of blocks or at
   // instructions that already have indexes.
-  while (Begin != MBB->begin() && !Indexes->hasIndex(*Begin))
+  while (Begin != MBB->begin() && !Indexes->hasIndex(*std::prev(Begin)))
     --Begin;
   while (End != MBB->end() && !Indexes->hasIndex(*End))
     ++End;
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Would it be realistic to replace these two loops with an `assert()` and have the callers perform the adjustments only when necessary?

(just as a suggestions, we don't necessarily need to do this as part of this diff)


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Comment at: llvm/test/CodeGen/Hexagon/mulhs.ll:2
 ; RUN: llc -march=hexagon < %s | FileCheck %s
+; RUN: llc -march=hexagon -early-live-intervals -verify-machineinstrs < %s | FileCheck %s
 
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Could you create a test in `unittests/MI/LiveIntervalTest.cpp` that just does a single call to `repairIntervalsInRange` instead of having this very indirect form of testing?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D110182/new/

https://reviews.llvm.org/D110182