Every pass deserves a name, even codegenprep.

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

diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp
index 9cd538128b60342260ce1af7c7fefa93cfb790dd..b8900ac3d77387eb9e5af4d0a4e2b430f708a372 100644 (file)
--- a/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -15,7 +15,16 @@
 
 #define DEBUG_TYPE "codegenprepare"
 #include "llvm/Transforms/Scalar.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/DominatorInternals.h"
+#include "llvm/Analysis/Dominators.h"
+#include "llvm/Analysis/InstructionSimplify.h"
+#include "llvm/Analysis/ProfileInfo.h"
+#include "llvm/Assembly/Writer.h"
 #include "llvm/Constants.h"
+#include "llvm/DataLayout.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Function.h"
 #include "llvm/IRBuilder.h"
@@ -23,14 +32,6 @@
 #include "llvm/Instructions.h"
 #include "llvm/IntrinsicInst.h"
 #include "llvm/Pass.h"
-#include "llvm/ADT/DenseMap.h"
-#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"
 #include "llvm/Support/CallSite.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
@@ -38,7 +39,6 @@
 #include "llvm/Support/PatternMatch.h"
 #include "llvm/Support/ValueHandle.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/DataLayout.h"
 #include "llvm/Target/TargetLibraryInfo.h"
 #include "llvm/Target/TargetLowering.h"
 #include "llvm/Transforms/Utils/AddrModeMatcher.h"
@@ -106,6 +106,8 @@ namespace {
       }
     bool runOnFunction(Function &F);
 
+    const char *getPassName() const { return "CodeGen Prepare"; }
+
     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
       AU.addPreserved<DominatorTree>();
       AU.addPreserved<ProfileInfo>();
@@ -125,7 +127,7 @@ 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);
   };
 }
@@ -148,7 +150,7 @@ bool CodeGenPrepare::runOnFunction(Function &F) {
   TLInfo = &getAnalysis<TargetLibraryInfo>();
   DT = getAnalysisIfAvailable<DominatorTree>();
   PFI = getAnalysisIfAvailable<ProfileInfo>();
-  OptSize = F.getFnAttributes().hasAttribute(Attributes::OptimizeForSize);
+  OptSize = F.getFnAttributes().hasAttribute(Attribute::OptimizeForSize);
 
   /// This optimization identifies DIV instructions that can be
   /// profitably bypassed and carried out with a shorter, faster divide.
@@ -194,9 +196,20 @@ bool CodeGenPrepare::runOnFunction(Function &F) {
           WorkList.insert(*II);
     }
 
-    for (SmallPtrSet<BasicBlock*, 8>::iterator
-           I = WorkList.begin(), E = WorkList.end(); I != E; ++I)
-      DeleteDeadBlock(*I);
+    // Delete the dead blocks and any of their dead successors.
+    MadeChange |= !WorkList.empty();
+    while (!WorkList.empty()) {
+      BasicBlock *BB = *WorkList.begin();
+      WorkList.erase(BB);
+      SmallVector<BasicBlock*, 2> Successors(succ_begin(BB), succ_end(BB));
+
+      DeleteDeadBlock(BB);
+      
+      for (SmallVectorImpl<BasicBlock*>::iterator
+             II = Successors.begin(), IE = Successors.end(); II != IE; ++II)
+        if (pred_begin(*II) == pred_end(*II))
+          WorkList.insert(*II);
+    }
 
     // Merge pairs of basic blocks with unconditional branches, connected by
     // a single edge.
@@ -689,10 +702,14 @@ 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();
@@ -706,16 +723,15 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
       return false;
   }
 
-  BasicBlock *BB = RI->getParent();
   if (PN && PN->getParent() != BB)
     return false;
 
   // It's not safe to eliminate the sign / zero extension of the return value.
   // See llvm::isInTailCallPosition().
   const Function *F = BB->getParent();
-  Attributes CallerRetAttr = F->getAttributes().getRetAttributes();
-  if (CallerRetAttr.hasAttribute(Attributes::ZExt) ||
-      CallerRetAttr.hasAttribute(Attributes::SExt))
+  Attribute CallerRetAttr = F->getAttributes().getRetAttributes();
+  if (CallerRetAttr.hasAttribute(Attribute::ZExt) ||
+      CallerRetAttr.hasAttribute(Attribute::SExt))
     return false;
 
   // Make sure there are no instructions between the PHI and return, or that the
@@ -772,11 +788,11 @@ 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();
+    Attribute CalleeRetAttr = CS.getAttributes().getRetAttributes();
     if (AttrBuilder(CalleeRetAttr).
-          removeAttribute(Attributes::NoAlias) !=
+          removeAttribute(Attribute::NoAlias) !=
         AttrBuilder(CallerRetAttr).
-          removeAttribute(Attributes::NoAlias))
+          removeAttribute(Attribute::NoAlias))
       continue;
 
     // Make sure the call instruction is followed by an unconditional branch to
@@ -933,7 +949,7 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
     DEBUG(dbgs() << "CGP: SINKING nonlocal addrmode: " << AddrMode << " for "
                  << *MemoryInst);
     Type *IntPtrTy =
-          TLI->getDataLayout()->getIntPtrType(Addr->getType());
+          TLI->getDataLayout()->getIntPtrType(AccessTy->getContext());
 
     Value *Result = 0;
 
@@ -1319,9 +1335,6 @@ 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);
 
@@ -1339,6 +1352,8 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
   while (CurInstIterator != BB.end())
     MadeChange |= OptimizeInst(CurInstIterator++);
 
+  MadeChange |= DupRetToEnableTailCallOpts(&BB);
+
   return MadeChange;
 }