[PATCH] New Loop Distribution pass

[Adam Nemet]

Thanks, Arnold!


================
Comment at: lib/Transforms/Scalar/LoopDistribute.cpp:147
@@ +146,3 @@
+
+  /// \brief Moves \p Other into this partition.  Other becomes empty after
+  /// this.
----------------
aschwaighofer wrote:
> Comment: It is the other way round. The code moves 'this' to the 'Other' partition.
Yeah, totally, the comment is backwards.

================
Comment at: lib/Transforms/Scalar/LoopDistribute.cpp:575
@@ +574,3 @@
+  void mergeAdjacentPartitionsIf(UnaryPredicate Predicate) {
+    for (auto I = PartitionContainer.begin(); I != PartitionContainer.end();) {
+      auto &FirstPartition = *I;
----------------
aschwaighofer wrote:
> Can we rewrite this nested loop to something like:
> 
>   InstPartion *PrevMatch = nullptr;
>   for (auto It = PC.begin(); It != PC.end(); ) {
>     auto DoesMatch = Predicate(*It);
>     if (PreMatch == nullptr && DoesMatch) {
>        PrevMatch = *It
>        ++It;
>     } else if (PreMatch != nullptr && DoesMatch) {
>       *It->move_to(PrevMatch);
>        It = PC.erase(It);
>     } else {
>       PrevMatch = nullptr;
>       ++It;
>     }
>   }
> 
Sure, if you prefer.

http://reviews.llvm.org/D8831

EMAIL PREFERENCES
  http://reviews.llvm.org/settings/panel/emailpreferences/