[PATCH] Quick look-up for block in loop

[Andrew Trick]

  Thanks Xiaofei. If you address my two inline comments, I think this is ready to checkin.


================
Comment at: include/llvm/Analysis/LoopInfo.h:278-281
@@ -274,1 +277,6 @@
+
+  void reverseBlock(unsigned from) {
+    std::reverse(Blocks.begin() + from, Blocks.end());
+    DenseBlockSet.clear();
+    DenseBlockSet.insert(Blocks.begin(), Blocks.end());
   }
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Why does this clear the cache?

================
Comment at: include/llvm/Analysis/LoopInfoImpl.h:421
@@ -420,3 +400,2 @@
   L->getSubLoopsVector().reserve(NumSubloops);
-  L->getBlocksVector().reserve(NumBlocks);
 }
----------------
Oh no. Why don't we reserve the block vector any more? Can you just add an API for it?


http://llvm-reviews.chandlerc.com/D2014