Added ARM::mls for armv6t2.

[oota-llvm.git] / lib / CodeGen / IfConversion.cpp

diff --git a/lib/CodeGen/IfConversion.cpp b/lib/CodeGen/IfConversion.cpp
index af496081f56dd9f12242fea25e23fab5e1657c30..d5e7ea59a74594920b957a91aac22edc67269850 100644 (file)
--- a/lib/CodeGen/IfConversion.cpp
+++ b/lib/CodeGen/IfConversion.cpp
@@ -144,9 +144,10 @@ namespace {
     const TargetLowering *TLI;
     const TargetInstrInfo *TII;
     bool MadeChange;
+    int FnNum;
   public:
     static char ID;
-    IfConverter() : MachineFunctionPass(&ID) {}
+    IfConverter() : MachineFunctionPass(&ID), FnNum(-1) {}
 
     virtual bool runOnMachineFunction(MachineFunction &MF);
     virtual const char *getPassName() const { return "If Converter"; }
@@ -225,7 +226,6 @@ bool IfConverter::runOnMachineFunction(MachineFunction &MF) {
   TII = MF.getTarget().getInstrInfo();
   if (!TII) return false;
 
-  static int FnNum = -1;
   DOUT << "\nIfcvt: function (" << ++FnNum <<  ") \'"
        << MF.getFunction()->getName() << "\'";
 
@@ -547,13 +547,16 @@ void IfConverter::ScanInstructions(BBInfo &BBI) {
     // fallthrough.
     if (!BBI.FalseBB)
       BBI.FalseBB = findFalseBlock(BBI.BB, BBI.TrueBB);  
-    assert(BBI.FalseBB && "Expected to find the fallthrough block!");
+    if (!BBI.FalseBB) {
+      // Malformed bcc? True and false blocks are the same?
+      BBI.IsUnpredicable = true;
+      return;
+    }
   }
 
   // Then scan all the instructions.
   BBI.NonPredSize = 0;
   BBI.ClobbersPred = false;
-  bool SeenCondBr = false;
   for (MachineBasicBlock::iterator I = BBI.BB->begin(), E = BBI.BB->end();
        I != E; ++I) {
     const TargetInstrDesc &TID = I->getDesc();
@@ -579,8 +582,6 @@ void IfConverter::ScanInstructions(BBInfo &BBI) {
       // Predicate modification instruction should end the block (except for
       // already predicated instructions and end of block branches).
       if (isCondBr) {
-        SeenCondBr = true;
-
         // A conditional branch is not predicable, but it may be eliminated.
         continue;
       }
@@ -666,6 +667,13 @@ IfConverter::BBInfo &IfConverter::AnalyzeBlock(MachineBasicBlock *BB,
     return BBI;
   }
 
+  // Do not ifcvt if true and false fallthrough blocks are the same.
+  if (!BBI.FalseBB) {
+    BBI.IsBeingAnalyzed = false;
+    BBI.IsAnalyzed = true;
+    return BBI;
+  }
+
   BBInfo &TrueBBI  = AnalyzeBlock(BBI.TrueBB, Tokens);
   BBInfo &FalseBBI = AnalyzeBlock(BBI.FalseBB, Tokens);
 
@@ -950,9 +958,7 @@ bool IfConverter::IfConvertTriangle(BBInfo &BBI, IfcvtKind Kind) {
     // Predicate the 'true' block after removing its branch.
     CvtBBI->NonPredSize -= TII->RemoveBranch(*CvtBBI->BB);
     PredicateBlock(*CvtBBI, CvtBBI->BB->end(), Cond);
-  }
 
-  if (!DupBB) {
     // Now merge the entry of the triangle with the true block.
     BBI.NonPredSize -= TII->RemoveBranch(*BBI.BB);
     MergeBlocks(BBI, *CvtBBI);
@@ -1217,7 +1223,7 @@ void IfConverter::MergeBlocks(BBInfo &ToBBI, BBInfo &FromBBI) {
   }
 
   // Now FromBBI always falls through to the next block!
-  if (NBB)
+  if (NBB && !FromBBI.BB->isSuccessor(NBB))
     FromBBI.BB->addSuccessor(NBB);
 
   std::copy(FromBBI.Predicate.begin(), FromBBI.Predicate.end(),