[llvm] [LAA] Add stencil group merging to reduce runtime pointer checks (PR #187252)

[David Sherwood via llvm-commits]

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@@ -562,7 +562,8 @@ class RuntimePointerChecking {
 
   /// Generate the checks and store it.  This also performs the grouping
   /// of pointers to reduce the number of memchecks necessary.
-  LLVM_ABI void generateChecks(MemoryDepChecker::DepCandidates &DepCands);
+  LLVM_ABI void generateChecks(MemoryDepChecker::DepCandidates &DepCands,
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david-arm wrote:

Oh I see. Yes, you're right! That's a shame. If the only way we can sensibly use `RuntimePointerChecking` is with a PredicatedScalarEvolution then it probably does make sense to store that in the RuntimePointerChecking class rather than ScalarEvolution. I would hope that having two different instances of ScalarEvolution would give the same answer to each question, but it would certainly be inefficient if we end up recalculating expressions that have already been cached.

https://github.com/llvm/llvm-project/pull/187252