[PATCH] D14296: [LV][LAA] Add a layer over SCEV to apply run-time checked knowledge on SCEV expressions

[Adam Nemet via llvm-commits]

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

LGTM.


================
Comment at: include/llvm/Transforms/Utils/LoopUtils.h:390
@@ +389,3 @@
+///   - lowers the number of expression rewrites.
+class PredicatedScalarEvolution {
+public:
----------------
Fair enough.

================
Comment at: lib/Transforms/Utils/LoopUtils.cpp:736
@@ +735,3 @@
+  const SCEV *Expr = SE.getSCEV(V);
+  auto II = RewriteMap.insert({Expr, {Generation, Expr}});
+
----------------
The inserted value is irrelevant here so we should use some invalid values.

Also, can we avoid this with DenseMap::FindAndConstruct?


http://reviews.llvm.org/D14296