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

diff --git a/lib/Transforms/Scalar/JumpThreading.cpp b/lib/Transforms/Scalar/JumpThreading.cpp
index dd42c59059abf4155ed9f474bafd78e9a630cc1d..4a4cd705e213cff4587276b0e3ffce2aec49f808 100644 (file)
--- a/lib/Transforms/Scalar/JumpThreading.cpp
+++ b/lib/Transforms/Scalar/JumpThreading.cpp
@@ -13,28 +13,28 @@
 
 #define DEBUG_TYPE "jump-threading"
 #include "llvm/Transforms/Scalar.h"
-#include "llvm/IntrinsicInst.h"
-#include "llvm/LLVMContext.h"
-#include "llvm/Pass.h"
-#include "llvm/Analysis/ConstantFolding.h"
-#include "llvm/Analysis/InstructionSimplify.h"
-#include "llvm/Analysis/LazyValueInfo.h"
-#include "llvm/Analysis/Loads.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/Transforms/Utils/SSAUpdater.h"
-#include "llvm/Target/TargetData.h"
-#include "llvm/Target/TargetLibraryInfo.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/DenseSet.h"
-#include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/InstructionSimplify.h"
+#include "llvm/Analysis/LazyValueInfo.h"
+#include "llvm/Analysis/Loads.h"
+#include "llvm/DataLayout.h"
+#include "llvm/IntrinsicInst.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/Pass.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ValueHandle.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetLibraryInfo.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Transforms/Utils/Local.h"
+#include "llvm/Transforms/Utils/SSAUpdater.h"
 using namespace llvm;
 
 STATISTIC(NumThreads, "Number of jumps threaded");
@@ -75,7 +75,7 @@ namespace {
   /// revectored to the false side of the second if.
   ///
   class JumpThreading : public FunctionPass {
-    TargetData *TD;
+    DataLayout *TD;
     TargetLibraryInfo *TLI;
     LazyValueInfo *LVI;
 #ifdef NDEBUG
@@ -147,7 +147,7 @@ FunctionPass *llvm::createJumpThreadingPass() { return new JumpThreading(); }
 ///
 bool JumpThreading::runOnFunction(Function &F) {
   DEBUG(dbgs() << "Jump threading on function '" << F.getName() << "'\n");
-  TD = getAnalysisIfAvailable<TargetData>();
+  TD = getAnalysisIfAvailable<DataLayout>();
   TLI = &getAnalysis<TargetLibraryInfo>();
   LVI = &getAnalysis<LazyValueInfo>();
 
@@ -216,19 +216,24 @@ bool JumpThreading::runOnFunction(Function &F) {
 }
 
 /// getJumpThreadDuplicationCost - Return the cost of duplicating this block to
-/// thread across it.
-static unsigned getJumpThreadDuplicationCost(const BasicBlock *BB) {
+/// thread across it. Stop scanning the block when passing the threshold.
+static unsigned getJumpThreadDuplicationCost(const BasicBlock *BB,
+                                             unsigned Threshold) {
   /// Ignore PHI nodes, these will be flattened when duplication happens.
   BasicBlock::const_iterator I = BB->getFirstNonPHI();
 
   // FIXME: THREADING will delete values that are just used to compute the
   // branch, so they shouldn't count against the duplication cost.
 
-
   // Sum up the cost of each instruction until we get to the terminator.  Don't
   // include the terminator because the copy won't include it.
   unsigned Size = 0;
   for (; !isa<TerminatorInst>(I); ++I) {
+
+    // Stop scanning the block if we've reached the threshold.
+    if (Size > Threshold)
+      return Size;
+
     // Debugger intrinsics don't incur code size.
     if (isa<DbgInfoIntrinsic>(I)) continue;
 
@@ -1337,7 +1342,7 @@ bool JumpThreading::ThreadEdge(BasicBlock *BB,
     return false;
   }
 
-  unsigned JumpThreadCost = getJumpThreadDuplicationCost(BB);
+  unsigned JumpThreadCost = getJumpThreadDuplicationCost(BB, Threshold);
   if (JumpThreadCost > Threshold) {
     DEBUG(dbgs() << "  Not threading BB '" << BB->getName()
           << "' - Cost is too high: " << JumpThreadCost << "\n");
@@ -1455,7 +1460,7 @@ bool JumpThreading::ThreadEdge(BasicBlock *BB,
   // At this point, the IR is fully up to date and consistent.  Do a quick scan
   // over the new instructions and zap any that are constants or dead.  This
   // frequently happens because of phi translation.
-  SimplifyInstructionsInBlock(NewBB, TD);
+  SimplifyInstructionsInBlock(NewBB, TD, TLI);
 
   // Threaded an edge!
   ++NumThreads;
@@ -1481,7 +1486,7 @@ bool JumpThreading::DuplicateCondBranchOnPHIIntoPred(BasicBlock *BB,
     return false;
   }
 
-  unsigned DuplicationCost = getJumpThreadDuplicationCost(BB);
+  unsigned DuplicationCost = getJumpThreadDuplicationCost(BB, Threshold);
   if (DuplicationCost > Threshold) {
     DEBUG(dbgs() << "  Not duplicating BB '" << BB->getName()
           << "' - Cost is too high: " << DuplicationCost << "\n");