Convert StringMap to using StringRef for its APIs.

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

diff --git a/lib/Transforms/Scalar/LoopUnswitch.cpp b/lib/Transforms/Scalar/LoopUnswitch.cpp
index 2bf194dbb73175966f49a44ad83f30c483ce1c74..100b8c7cfb945f22281bdab1c5fa3bb43d3219dd 100644 (file)
--- a/lib/Transforms/Scalar/LoopUnswitch.cpp
+++ b/lib/Transforms/Scalar/LoopUnswitch.cpp
@@ -32,6 +32,7 @@
 #include "llvm/DerivedTypes.h"
 #include "llvm/Function.h"
 #include "llvm/Instructions.h"
+#include "llvm/LLVMContext.h"
 #include "llvm/Analysis/ConstantFolding.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/LoopPass.h"
@@ -167,10 +168,10 @@ static Value *FindLIVLoopCondition(Value *Cond, Loop *L, bool &Changed) {
   if (isa<Constant>(Cond)) return 0;
 
   // TODO: Handle: br (VARIANT|INVARIANT).
-  // TODO: Hoist simple expressions out of loops.
-  if (Instruction *I = dyn_cast<Instruction>(Cond))
-    if (!L->contains(I->getParent()))
-      return 0;
+
+  // Hoist simple values out.
+  if (L->makeLoopInvariant(Cond, Changed))
+    return Cond;
 
   if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Cond))
     if (BO->getOpcode() == Instruction::And ||
@@ -190,8 +191,8 @@ static Value *FindLIVLoopCondition(Value *Cond, Loop *L, bool &Changed) {
 bool LoopUnswitch::runOnLoop(Loop *L, LPPassManager &LPM_Ref) {
   LI = &getAnalysis<LoopInfo>();
   LPM = &LPM_Ref;
-  DF = getAnalysisToUpdate<DominanceFrontier>();
-  DT = getAnalysisToUpdate<DominatorTree>();
+  DF = getAnalysisIfAvailable<DominanceFrontier>();
+  DT = getAnalysisIfAvailable<DominatorTree>();
   currentLoop = L;
   Function *F = currentLoop->getHeader()->getParent();
   bool Changed = false;
@@ -215,6 +216,7 @@ bool LoopUnswitch::runOnLoop(Loop *L, LPPassManager &LPM_Ref) {
 /// and profitable.
 bool LoopUnswitch::processCurrentLoop() {
   bool Changed = false;
+  LLVMContext &Context = currentLoop->getHeader()->getContext();
 
   // Loop over all of the basic blocks in the loop.  If we find an interior
   // block that is branching on a loop-invariant condition, we can unswitch this
@@ -232,7 +234,7 @@ bool LoopUnswitch::processCurrentLoop() {
         Value *LoopCond = FindLIVLoopCondition(BI->getCondition(), 
                                                currentLoop, Changed);
         if (LoopCond && UnswitchIfProfitable(LoopCond, 
-                                             ConstantInt::getTrue())) {
+                                             Context.getTrue())) {
           ++NumBranches;
           return true;
         }
@@ -262,7 +264,7 @@ bool LoopUnswitch::processCurrentLoop() {
         Value *LoopCond = FindLIVLoopCondition(SI->getCondition(), 
                                                currentLoop, Changed);
         if (LoopCond && UnswitchIfProfitable(LoopCond, 
-                                             ConstantInt::getTrue())) {
+                                             Context.getTrue())) {
           ++NumSelects;
           return true;
         }
@@ -302,7 +304,7 @@ static bool isTrivialLoopExitBlockHelper(Loop *L, BasicBlock *BB,
   // Okay, everything after this looks good, check to make sure that this block
   // doesn't include any side effects.
   for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
-    if (I->mayWriteToMemory())
+    if (I->mayHaveSideEffects())
       return false;
   
   return true;
@@ -336,6 +338,7 @@ bool LoopUnswitch::IsTrivialUnswitchCondition(Value *Cond, Constant **Val,
                                        BasicBlock **LoopExit) {
   BasicBlock *Header = currentLoop->getHeader();
   TerminatorInst *HeaderTerm = Header->getTerminator();
+  LLVMContext &Context = Header->getContext();
   
   BasicBlock *LoopExitBB = 0;
   if (BranchInst *BI = dyn_cast<BranchInst>(HeaderTerm)) {
@@ -350,10 +353,10 @@ bool LoopUnswitch::IsTrivialUnswitchCondition(Value *Cond, Constant **Val,
     // this.
     if ((LoopExitBB = isTrivialLoopExitBlock(currentLoop, 
                                              BI->getSuccessor(0)))) {
-      if (Val) *Val = ConstantInt::getTrue();
+      if (Val) *Val = Context.getTrue();
     } else if ((LoopExitBB = isTrivialLoopExitBlock(currentLoop, 
                                                     BI->getSuccessor(1)))) {
-      if (Val) *Val = ConstantInt::getFalse();
+      if (Val) *Val = Context.getFalse();
     }
   } else if (SwitchInst *SI = dyn_cast<SwitchInst>(HeaderTerm)) {
     // If this isn't a switch on Cond, we can't handle it.
@@ -385,7 +388,7 @@ bool LoopUnswitch::IsTrivialUnswitchCondition(Value *Cond, Constant **Val,
   // part of the loop that the code *would* execute.  We already checked the
   // tail, check the header now.
   for (BasicBlock::iterator I = Header->begin(), E = Header->end(); I != E; ++I)
-    if (I->mayWriteToMemory())
+    if (I->mayHaveSideEffects())
       return false;
   return true;
 }
@@ -432,9 +435,6 @@ bool LoopUnswitch::UnswitchIfProfitable(Value *LoopCond, Constant *Val){
   initLoopData();
   Function *F = loopHeader->getParent();
 
-  // Do not unswitch if the function is optimized for size.
-  if (!F->isDeclaration() && F->hasFnAttr(Attribute::OptimizeForSize))
-    return false;
 
   // Check to see if it would be profitable to unswitch current loop.
   unsigned Cost = getLoopUnswitchCost(LoopCond);
@@ -442,6 +442,8 @@ bool LoopUnswitch::UnswitchIfProfitable(Value *LoopCond, Constant *Val){
   // Do not do non-trivial unswitch while optimizing for size.
   if (Cost && OptimizeForSize)
     return false;
+  if (Cost && !F->isDeclaration() && F->hasFnAttr(Attribute::OptimizeForSize))
+    return false;
 
   if (Cost > Threshold) {
     // FIXME: this should estimate growth by the amount of code shared by the
@@ -509,8 +511,8 @@ void LoopUnswitch::EmitPreheaderBranchOnCondition(Value *LIC, Constant *Val,
   // code is the true version and the new code is the false version.
   Value *BranchVal = LIC;
   if (!isa<ConstantInt>(Val) || Val->getType() != Type::Int1Ty)
-    BranchVal = new ICmpInst(ICmpInst::ICMP_EQ, LIC, Val, "tmp", InsertPt);
-  else if (Val != ConstantInt::getTrue())
+    BranchVal = new ICmpInst(InsertPt, ICmpInst::ICMP_EQ, LIC, Val, "tmp");
+  else if (Val != Val->getContext().getTrue())
     // We want to enter the new loop when the condition is true.
     std::swap(TrueDest, FalseDest);
 
@@ -580,7 +582,7 @@ void LoopUnswitch::SplitExitEdges(Loop *L,
       BasicBlock* EndBlock;
       if (NewExitBlock->getSinglePredecessor() == ExitBlock) {
         EndBlock = NewExitBlock;
-        NewExitBlock = EndBlock->getSinglePredecessor();;
+        NewExitBlock = EndBlock->getSinglePredecessor();
       } else {
         EndBlock = ExitBlock;
       }
@@ -818,7 +820,7 @@ void LoopUnswitch::RemoveBlockIfDead(BasicBlock *BB,
     // Anything that uses the instructions in this basic block should have their
     // uses replaced with undefs.
     if (!I->use_empty())
-      I->replaceAllUsesWith(UndefValue::get(I->getType()));
+      I->replaceAllUsesWith(I->getContext().getUndef(I->getType()));
   }
   
   // If this is the edge to the header block for a loop, remove the loop and
@@ -899,6 +901,8 @@ void LoopUnswitch::RewriteLoopBodyWithConditionConstant(Loop *L, Value *LIC,
   // selects, switches.
   std::vector<User*> Users(LIC->use_begin(), LIC->use_end());
   std::vector<Instruction*> Worklist;
+  LLVMContext &Context = Val->getContext();
+
 
   // If we know that LIC == Val, or that LIC == NotVal, just replace uses of LIC
   // in the loop with the appropriate one directly.
@@ -907,7 +911,7 @@ void LoopUnswitch::RewriteLoopBodyWithConditionConstant(Loop *L, Value *LIC,
     if (IsEqual)
       Replacement = Val;
     else
-      Replacement = ConstantInt::get(Type::Int1Ty, 
+      Replacement = Context.getConstantInt(Type::Int1Ty, 
                                      !cast<ConstantInt>(Val)->getZExtValue());
     
     for (unsigned i = 0, e = Users.size(); i != e; ++i)
@@ -947,7 +951,7 @@ void LoopUnswitch::RewriteLoopBodyWithConditionConstant(Loop *L, Value *LIC,
               
               Instruction* OldTerm = Old->getTerminator();
               BranchInst::Create(Split, SISucc,
-                                 ConstantInt::getTrue(), OldTerm);
+                                 Context.getTrue(), OldTerm);
 
               LPM->deleteSimpleAnalysisValue(Old->getTerminator(), L);
               Old->getTerminator()->eraseFromParent();
@@ -988,7 +992,7 @@ void LoopUnswitch::SimplifyCode(std::vector<Instruction*> &Worklist, Loop *L) {
     Worklist.pop_back();
     
     // Simple constant folding.
-    if (Constant *C = ConstantFoldInstruction(I)) {
+    if (Constant *C = ConstantFoldInstruction(I, I->getContext())) {
       ReplaceUsesOfWith(I, C, Worklist, L, LPM);
       continue;
     }