instcombine: Migrate ffs* optimizations

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

diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp
index 65249153bd043a82be10a9f847618741a51f9881..b608a5535edcde5d8e56353d34e157b40a547c6a 100644 (file)
--- a/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -27,6 +27,7 @@
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/Dominators.h"
+#include "llvm/Analysis/DominatorInternals.h"
 #include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/Analysis/ProfileInfo.h"
 #include "llvm/Assembly/Writer.h"
@@ -37,7 +38,7 @@
 #include "llvm/Support/PatternMatch.h"
 #include "llvm/Support/ValueHandle.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/Target/TargetData.h"
+#include "llvm/DataLayout.h"
 #include "llvm/Target/TargetLibraryInfo.h"
 #include "llvm/Target/TargetLowering.h"
 #include "llvm/Transforms/Utils/AddrModeMatcher.h"
@@ -124,7 +125,7 @@ namespace {
     bool MoveExtToFormExtLoad(Instruction *I);
     bool OptimizeExtUses(Instruction *I);
     bool OptimizeSelectInst(SelectInst *SI);
-    bool DupRetToEnableTailCallOpts(ReturnInst *RI);
+    bool DupRetToEnableTailCallOpts(BasicBlock *BB);
     bool PlaceDbgValues(Function &F);
   };
 }
@@ -147,14 +148,15 @@ bool CodeGenPrepare::runOnFunction(Function &F) {
   TLInfo = &getAnalysis<TargetLibraryInfo>();
   DT = getAnalysisIfAvailable<DominatorTree>();
   PFI = getAnalysisIfAvailable<ProfileInfo>();
-  OptSize = F.hasFnAttr(Attribute::OptimizeForSize);
+  OptSize = F.getFnAttributes().hasAttribute(Attributes::OptimizeForSize);
 
   /// This optimization identifies DIV instructions that can be
   /// profitably bypassed and carried out with a shorter, faster divide.
   if (TLI && TLI->isSlowDivBypassed()) {
-    const DenseMap<Type*, Type*> &BypassTypeMap = TLI->getBypassSlowDivTypes();
+    const DenseMap<unsigned int, unsigned int> &BypassWidths =
+       TLI->getBypassSlowDivWidths();
     for (Function::iterator I = F.begin(); I != F.end(); I++)
-      EverMadeChange |= bypassSlowDivision(F, I, BypassTypeMap);
+      EverMadeChange |= bypassSlowDivision(F, I, BypassWidths);
   }
 
   // Eliminate blocks that contain only PHI nodes and an
@@ -169,7 +171,7 @@ bool CodeGenPrepare::runOnFunction(Function &F) {
   bool MadeChange = true;
   while (MadeChange) {
     MadeChange = false;
-    for (Function::iterator I = F.begin(), E = F.end(); I != E; ) {
+    for (Function::iterator I = F.begin(); I != F.end(); ) {
       BasicBlock *BB = I++;
       MadeChange |= OptimizeBlock(*BB);
     }
@@ -224,7 +226,8 @@ bool CodeGenPrepare::EliminateFallThrough(Function &F) {
     // edge, just collapse it.
     BasicBlock *SinglePred = BB->getSinglePredecessor();
 
-    if (!SinglePred || SinglePred == BB) continue;
+    // Don't merge if BB's address is taken.
+    if (!SinglePred || SinglePred == BB || BB->hasAddressTaken()) continue;
 
     BranchInst *Term = dyn_cast<BranchInst>(SinglePred->getTerminator());
     if (Term && !Term->isConditional()) {
@@ -619,7 +622,7 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
     // happens.
     WeakVH IterHandle(CurInstIterator);
 
-    replaceAndRecursivelySimplify(CI, RetVal, TLI ? TLI->getTargetData() : 0,
+    replaceAndRecursivelySimplify(CI, RetVal, TLI ? TLI->getDataLayout() : 0,
                                   TLInfo, ModifiedDT ? 0 : DT);
 
     // If the iterator instruction was recursively deleted, start over at the
@@ -643,8 +646,8 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
   // From here on out we're working with named functions.
   if (CI->getCalledFunction() == 0) return false;
 
-  // We'll need TargetData from here on out.
-  const TargetData *TD = TLI ? TLI->getTargetData() : 0;
+  // We'll need DataLayout from here on out.
+  const DataLayout *TD = TLI ? TLI->getDataLayout() : 0;
   if (!TD) return false;
 
   // Lower all default uses of _chk calls.  This is very similar
@@ -686,10 +689,14 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
 ///   %tmp2 = tail call i32 @f2()
 ///   ret i32 %tmp2
 /// @endcode
-bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
+bool CodeGenPrepare::DupRetToEnableTailCallOpts(BasicBlock *BB) {
   if (!TLI)
     return false;
 
+  ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator());
+  if (!RI)
+    return false;
+
   PHINode *PN = 0;
   BitCastInst *BCI = 0;
   Value *V = RI->getReturnValue();
@@ -703,7 +710,6 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
       return false;
   }
 
-  BasicBlock *BB = RI->getParent();
   if (PN && PN->getParent() != BB)
     return false;
 
@@ -711,7 +717,8 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
   // See llvm::isInTailCallPosition().
   const Function *F = BB->getParent();
   Attributes CallerRetAttr = F->getAttributes().getRetAttributes();
-  if ((CallerRetAttr & Attribute::ZExt) || (CallerRetAttr & Attribute::SExt))
+  if (CallerRetAttr.hasAttribute(Attributes::ZExt) ||
+      CallerRetAttr.hasAttribute(Attributes::SExt))
     return false;
 
   // Make sure there are no instructions between the PHI and return, or that the
@@ -769,7 +776,10 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
     // Conservatively require the attributes of the call to match those of the
     // return. Ignore noalias because it doesn't affect the call sequence.
     Attributes CalleeRetAttr = CS.getAttributes().getRetAttributes();
-    if ((CalleeRetAttr ^ CallerRetAttr) & ~Attribute::NoAlias)
+    if (AttrBuilder(CalleeRetAttr).
+          removeAttribute(Attributes::NoAlias) !=
+        AttrBuilder(CallerRetAttr).
+          removeAttribute(Attributes::NoAlias))
       continue;
 
     // Make sure the call instruction is followed by an unconditional branch to
@@ -786,7 +796,7 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
   }
 
   // If we eliminated all predecessors of the block, delete the block now.
-  if (Changed && pred_begin(BB) == pred_end(BB))
+  if (Changed && !BB->hasAddressTaken() && pred_begin(BB) == pred_end(BB))
     BB->eraseFromParent();
 
   return Changed;
@@ -926,7 +936,7 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
     DEBUG(dbgs() << "CGP: SINKING nonlocal addrmode: " << AddrMode << " for "
                  << *MemoryInst);
     Type *IntPtrTy =
-          TLI->getTargetData()->getIntPtrType(AccessTy->getContext());
+          TLI->getDataLayout()->getIntPtrType(AccessTy->getContext());
 
     Value *Result = 0;
 
@@ -1312,9 +1322,6 @@ bool CodeGenPrepare::OptimizeInst(Instruction *I) {
   if (CallInst *CI = dyn_cast<CallInst>(I))
     return OptimizeCallInst(CI);
 
-  if (ReturnInst *RI = dyn_cast<ReturnInst>(I))
-    return DupRetToEnableTailCallOpts(RI);
-
   if (SelectInst *SI = dyn_cast<SelectInst>(I))
     return OptimizeSelectInst(SI);
 
@@ -1329,9 +1336,11 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
   bool MadeChange = false;
 
   CurInstIterator = BB.begin();
-  for (BasicBlock::iterator E = BB.end(); CurInstIterator != E; )
+  while (CurInstIterator != BB.end())
     MadeChange |= OptimizeInst(CurInstIterator++);
 
+  MadeChange |= DupRetToEnableTailCallOpts(&BB);
+
   return MadeChange;
 }