[llvm] r184527 - SLP Vectorizer: do not search for store-chains that are wider than the vector-register size.

[Nadav Rotem]

Author: nadav
Date: Thu Jun 20 23:18:13 2013
New Revision: 184527

URL: http://llvm.org/viewvc/llvm-project?rev=184527&view=rev
Log:
SLP Vectorizer: do not search for store-chains that are wider than the vector-register size.


Modified:
    llvm/trunk/lib/Transforms/Vectorize/VecUtils.cpp

Modified: llvm/trunk/lib/Transforms/Vectorize/VecUtils.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Vectorize/VecUtils.cpp?rev=184527&r1=184526&r2=184527&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Vectorize/VecUtils.cpp (original)
+++ llvm/trunk/lib/Transforms/Vectorize/VecUtils.cpp Thu Jun 20 23:18:13 2013
@@ -141,9 +141,11 @@ bool BoUpSLP::vectorizeStoreChain(ArrayR
     }
   }
 
-  if (Changed)
-    return true;
+  if (Changed || ChainLen > VF)
+    return Changed;
 
+  // Handle short chains. This helps us catch types such as <3 x float> that
+  // are smaller than vector size.
   int Cost = getTreeCost(Chain);
   if (Cost < CostThreshold) {
     DEBUG(dbgs() << "SLP: Found store chain cost = " << Cost