[llvm] r214963 - Add a new option -run-slp-after-loop-vectorization.

[James Molloy]

Author: jamesm
Date: Wed Aug  6 07:56:19 2014
New Revision: 214963

URL: http://llvm.org/viewvc/llvm-project?rev=214963&view=rev
Log:
Add a new option -run-slp-after-loop-vectorization.

This swaps the order of the loop vectorizer and the SLP/BB vectorizers. It is disabled by default so we can do performance testing - ideally we want to change to having the loop vectorizer running first, and the SLP vectorizer using its leftovers instead of the other way around.


Modified:
    llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp

Modified: llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp?rev=214963&r1=214962&r2=214963&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp Wed Aug  6 07:56:19 2014
@@ -57,6 +57,13 @@ static cl::opt<bool> RunLoadCombine("com
                                     cl::Hidden,
                                     cl::desc("Run the load combining pass"));
 
+static cl::opt<bool>
+RunSLPAfterLoopVectorization("run-slp-after-loop-vectorization",
+  cl::init(false), cl::Hidden,
+  cl::desc("Run the SLP vectorizer (and BB vectorizer) after the Loop "
+           "vectorizer instead of before"));
+
+
 PassManagerBuilder::PassManagerBuilder() {
     OptLevel = 2;
     SizeLevel = 0;
@@ -227,21 +234,23 @@ void PassManagerBuilder::populateModuleP
 
   if (RerollLoops)
     MPM.add(createLoopRerollPass());
-  if (SLPVectorize)
-    MPM.add(createSLPVectorizerPass());   // Vectorize parallel scalar chains.
-
-  if (BBVectorize) {
-    MPM.add(createBBVectorizePass());
-    MPM.add(createInstructionCombiningPass());
-    addExtensionsToPM(EP_Peephole, MPM);
-    if (OptLevel > 1 && UseGVNAfterVectorization)
-      MPM.add(createGVNPass());           // Remove redundancies
-    else
-      MPM.add(createEarlyCSEPass());      // Catch trivial redundancies
-
-    // BBVectorize may have significantly shortened a loop body; unroll again.
-    if (!DisableUnrollLoops)
-      MPM.add(createLoopUnrollPass());
+  if (!RunSLPAfterLoopVectorization) {
+    if (SLPVectorize)
+      MPM.add(createSLPVectorizerPass());   // Vectorize parallel scalar chains.
+
+    if (BBVectorize) {
+      MPM.add(createBBVectorizePass());
+      MPM.add(createInstructionCombiningPass());
+      addExtensionsToPM(EP_Peephole, MPM);
+      if (OptLevel > 1 && UseGVNAfterVectorization)
+        MPM.add(createGVNPass());           // Remove redundancies
+      else
+        MPM.add(createEarlyCSEPass());      // Catch trivial redundancies
+
+      // BBVectorize may have significantly shortened a loop body; unroll again.
+      if (!DisableUnrollLoops)
+        MPM.add(createLoopUnrollPass());
+    }
   }
 
   if (LoadCombine)
@@ -263,6 +272,26 @@ void PassManagerBuilder::populateModuleP
   // as function calls, so that we can only pass them when the vectorizer
   // changed the code.
   MPM.add(createInstructionCombiningPass());
+
+  if (RunSLPAfterLoopVectorization) {
+    if (SLPVectorize)
+      MPM.add(createSLPVectorizerPass());   // Vectorize parallel scalar chains.
+
+    if (BBVectorize) {
+      MPM.add(createBBVectorizePass());
+      MPM.add(createInstructionCombiningPass());
+      addExtensionsToPM(EP_Peephole, MPM);
+      if (OptLevel > 1 && UseGVNAfterVectorization)
+        MPM.add(createGVNPass());           // Remove redundancies
+      else
+        MPM.add(createEarlyCSEPass());      // Catch trivial redundancies
+
+      // BBVectorize may have significantly shortened a loop body; unroll again.
+      if (!DisableUnrollLoops)
+        MPM.add(createLoopUnrollPass());
+    }
+  }
+
   addExtensionsToPM(EP_Peephole, MPM);
   MPM.add(createCFGSimplificationPass());