[llvm] r279462 - MSSA: Factor out phi node placement

[Daniel Berlin via llvm-commits]

Author: dannyb
Date: Mon Aug 22 14:14:30 2016
New Revision: 279462

URL: http://llvm.org/viewvc/llvm-project?rev=279462&view=rev
Log:
MSSA: Factor out phi node placement

Modified:
    llvm/trunk/include/llvm/Transforms/Utils/MemorySSA.h
    llvm/trunk/lib/Transforms/Utils/MemorySSA.cpp

Modified: llvm/trunk/include/llvm/Transforms/Utils/MemorySSA.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Utils/MemorySSA.h?rev=279462&r1=279461&r2=279462&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Utils/MemorySSA.h (original)
+++ llvm/trunk/include/llvm/Transforms/Utils/MemorySSA.h Mon Aug 22 14:14:30 2016
@@ -616,6 +616,8 @@ private:
   MemoryAccess *findDominatingDef(BasicBlock *, enum InsertionPlace);
   void removeFromLookups(MemoryAccess *);
 
+  void placePHINodes(const SmallPtrSetImpl<BasicBlock *> &,
+                     const SmallPtrSetImpl<BasicBlock *> &);
   MemoryAccess *renameBlock(BasicBlock *, MemoryAccess *);
   void renamePass(DomTreeNode *, MemoryAccess *IncomingVal,
                   SmallPtrSet<BasicBlock *, 16> &Visited);

Modified: llvm/trunk/lib/Transforms/Utils/MemorySSA.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/MemorySSA.cpp?rev=279462&r1=279461&r2=279462&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/MemorySSA.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/MemorySSA.cpp Mon Aug 22 14:14:30 2016
@@ -1459,6 +1459,27 @@ void MemorySSA::OptimizeUses::optimizeUs
                         LocStackInfo);
 }
 
+void MemorySSA::placePHINodes(
+    const SmallPtrSetImpl<BasicBlock *> &DefiningBlocks,
+    const SmallPtrSetImpl<BasicBlock *> &LiveInBlocks) {
+  // Determine where our MemoryPhi's should go
+  ForwardIDFCalculator IDFs(*DT);
+  IDFs.setDefiningBlocks(DefiningBlocks);
+  IDFs.setLiveInBlocks(LiveInBlocks);
+  SmallVector<BasicBlock *, 32> IDFBlocks;
+  IDFs.calculate(IDFBlocks);
+
+  // Now place MemoryPhi nodes.
+  for (auto &BB : IDFBlocks) {
+    // Insert phi node
+    AccessList *Accesses = getOrCreateAccessList(BB);
+    MemoryPhi *Phi = new MemoryPhi(BB->getContext(), BB, NextID++);
+    ValueToMemoryAccess[BB] = Phi;
+    // Phi's always are placed at the front of the block.
+    Accesses->push_front(Phi);
+  }
+}
+
 void MemorySSA::buildMemorySSA() {
   // We create an access to represent "live on entry", for things like
   // arguments or users of globals, where the memory they use is defined before
@@ -1528,23 +1549,7 @@ void MemorySSA::buildMemorySSA() {
     // live into it to.
     LiveInBlockWorklist.append(pred_begin(BB), pred_end(BB));
   }
-
-  // Determine where our MemoryPhi's should go
-  ForwardIDFCalculator IDFs(*DT);
-  IDFs.setDefiningBlocks(DefiningBlocks);
-  IDFs.setLiveInBlocks(LiveInBlocks);
-  SmallVector<BasicBlock *, 32> IDFBlocks;
-  IDFs.calculate(IDFBlocks);
-
-  // Now place MemoryPhi nodes.
-  for (auto &BB : IDFBlocks) {
-    // Insert phi node
-    AccessList *Accesses = getOrCreateAccessList(BB);
-    MemoryPhi *Phi = new MemoryPhi(BB->getContext(), BB, NextID++);
-    ValueToMemoryAccess[BB] = Phi;
-    // Phi's always are placed at the front of the block.
-    Accesses->push_front(Phi);
-  }
+  placePHINodes(DefiningBlocks, LiveInBlocks);
 
   // Now do regular SSA renaming on the MemoryDef/MemoryUse. Visited will get
   // filled in with all blocks.