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[oota-llvm.git] / lib / Transforms / Scalar / LoopUnswitch.cpp

diff --git a/lib/Transforms/Scalar/LoopUnswitch.cpp b/lib/Transforms/Scalar/LoopUnswitch.cpp
index 00ecc749af05b4809feb3218f065539812be5dbc..d41da4a9a9873f442508d40034f1e1979bd6390c 100644 (file)
--- a/lib/Transforms/Scalar/LoopUnswitch.cpp
+++ b/lib/Transforms/Scalar/LoopUnswitch.cpp
@@ -28,25 +28,25 @@
 
 #define DEBUG_TYPE "loop-unswitch"
 #include "llvm/Transforms/Scalar.h"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Function.h"
-#include "llvm/Instructions.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/CodeMetrics.h"
+#include "llvm/Analysis/Dominators.h"
 #include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/LoopPass.h"
-#include "llvm/Analysis/Dominators.h"
 #include "llvm/Analysis/ScalarEvolution.h"
-#include "llvm/Transforms/Utils/Cloning.h"
-#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/STLExtras.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/Instructions.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Transforms/Utils/Cloning.h"
+#include "llvm/Transforms/Utils/Local.h"
 #include <algorithm>
 #include <map>
 #include <set>
@@ -409,15 +409,6 @@ bool LoopUnswitch::processCurrentLoop() {
   if (!currentLoop->isSafeToClone())
     return false;
 
-  // Loops with invokes, whose unwind edge escapes the loop, cannot be
-  // unswitched because splitting their edges are non-trivial and don't preserve
-  // loop simplify information.
-  for (Loop::block_iterator I = currentLoop->block_begin(),
-         E = currentLoop->block_end(); I != E; ++I)
-    if (const InvokeInst *II = dyn_cast<InvokeInst>((*I)->getTerminator()))
-      if (!currentLoop->contains(II->getUnwindDest()))
-        return false;
-
   // Without dedicated exits, splitting the exit edge may fail.
   if (!currentLoop->hasDedicatedExits())
     return false;
@@ -633,11 +624,10 @@ bool LoopUnswitch::IsTrivialUnswitchCondition(Value *Cond, Constant **Val,
 /// LoopCond == Val to simplify the loop.  If we decide that this is profitable,
 /// unswitch the loop, reprocess the pieces, then return true.
 bool LoopUnswitch::UnswitchIfProfitable(Value *LoopCond, Constant *Val) {
-
   Function *F = loopHeader->getParent();
-
   Constant *CondVal = 0;
   BasicBlock *ExitBlock = 0;
+
   if (IsTrivialUnswitchCondition(LoopCond, &CondVal, &ExitBlock)) {
     // If the condition is trivial, always unswitch. There is no code growth
     // for this case.
@@ -648,7 +638,8 @@ bool LoopUnswitch::UnswitchIfProfitable(Value *LoopCond, Constant *Val) {
   // Check to see if it would be profitable to unswitch current loop.
 
   // Do not do non-trivial unswitch while optimizing for size.
-  if (OptimizeForSize || F->hasFnAttr(Attribute::OptimizeForSize))
+  if (OptimizeForSize ||
+      F->getFnAttributes().hasAttribute(Attributes::OptimizeForSize))
     return false;
 
   UnswitchNontrivialCondition(LoopCond, Val, currentLoop);
@@ -697,8 +688,8 @@ void LoopUnswitch::EmitPreheaderBranchOnCondition(Value *LIC, Constant *Val,
 
   // If either edge is critical, split it. This helps preserve LoopSimplify
   // form for enclosing loops.
-  SplitCriticalEdge(BI, 0, this);
-  SplitCriticalEdge(BI, 1, this);
+  SplitCriticalEdge(BI, 0, this, false, false, true);
+  SplitCriticalEdge(BI, 1, this, false, false, true);
 }
 
 /// UnswitchTrivialCondition - Given a loop that has a trivial unswitchable
@@ -916,13 +907,9 @@ void LoopUnswitch::UnswitchNontrivialCondition(Value *LIC, Constant *Val,
 /// specified.
 static void RemoveFromWorklist(Instruction *I,
                                std::vector<Instruction*> &Worklist) {
-  std::vector<Instruction*>::iterator WI = std::find(Worklist.begin(),
-                                                     Worklist.end(), I);
-  while (WI != Worklist.end()) {
-    unsigned Offset = WI-Worklist.begin();
-    Worklist.erase(WI);
-    WI = std::find(Worklist.begin()+Offset, Worklist.end(), I);
-  }
+
+  Worklist.erase(std::remove(Worklist.begin(), Worklist.end(), I),
+                 Worklist.end());
 }
 
 /// ReplaceUsesOfWith - When we find that I really equals V, remove I from the
@@ -1224,8 +1211,8 @@ void LoopUnswitch::SimplifyCode(std::vector<Instruction*> &Worklist, Loop *L) {
 
     // See if instruction simplification can hack this up.  This is common for
     // things like "select false, X, Y" after unswitching made the condition be
-    // 'false'.
-    if (Value *V = SimplifyInstruction(I, 0, 0, DT))
+    // 'false'.  TODO: update the domtree properly so we can pass it here.
+    if (Value *V = SimplifyInstruction(I))
       if (LI->replacementPreservesLCSSAForm(I, V)) {
         ReplaceUsesOfWith(I, V, Worklist, L, LPM);
         continue;