Make better use of the PHINode API.

Change various bits of code to make better use of the existing PHINode
API, to insulate them from forthcoming changes in how PHINodes store
their operands.

llvm-svn: 133434

7 files changed, 34 insertions, 21 deletions

diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index ed006f0fc87..24b5e2d52a8 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -1079,12 +1079,16 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
     AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
     break;
 
-  case Instruction::PHI:
+  case Instruction::PHI: {
+    const PHINode &PN = cast<PHINode>(I);
     Code = bitc::FUNC_CODE_INST_PHI;
-    Vals.push_back(VE.getTypeID(I.getType()));
-    for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
-      Vals.push_back(VE.getValueID(I.getOperand(i)));
+    Vals.push_back(VE.getTypeID(PN.getType()));
+    for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
+      Vals.push_back(VE.getValueID(PN.getIncomingValue(i)));
+      Vals.push_back(VE.getValueID(PN.getIncomingBlock(i)));
+    }
     break;
+  }
 
   case Instruction::Alloca:
     Code = bitc::FUNC_CODE_INST_ALLOCA;
diff --git a/llvm/lib/Target/CppBackend/CPPBackend.cpp b/llvm/lib/Target/CppBackend/CPPBackend.cpp
index d7d40c840b4..2ba773bd5e5 100644
--- a/llvm/lib/Target/CppBackend/CPPBackend.cpp
+++ b/llvm/lib/Target/CppBackend/CPPBackend.cpp
@@ -1353,9 +1353,10 @@ void CppWriter::printInstruction(const Instruction *I,
     printEscapedString(phi->getName());
     Out << "\", " << bbname << ");";
     nl(Out);
-    for (unsigned i = 0; i < phi->getNumOperands(); i+=2) {
+    for (unsigned i = 0; i < phi->getNumIncomingValues(); ++i) {
       Out << iName << "->addIncoming("
-          << opNames[i] << ", " << opNames[i+1] << ");";
+          << opNames[PHINode::getOperandNumForIncomingValue(i)] << ", "
+          << opNames[PHINode::getOperandNumForIncomingBlock(i)] << ");";
       nl(Out);
     }
     break;
diff --git a/llvm/lib/Transforms/Scalar/GVN.cpp b/llvm/lib/Transforms/Scalar/GVN.cpp
index 0e1e6f32e4c..759e681f5e8 100644
--- a/llvm/lib/Transforms/Scalar/GVN.cpp
+++ b/llvm/lib/Transforms/Scalar/GVN.cpp
@@ -1190,8 +1190,10 @@ static Value *ConstructSSAForLoadSet(LoadInst *LI,
     // escaping uses to any values that are operands to these PHIs.
     for (unsigned i = 0, e = NewPHIs.size(); i != e; ++i) {
       PHINode *P = NewPHIs[i];
-      for (unsigned ii = 0, ee = P->getNumIncomingValues(); ii != ee; ++ii)
-        AA->addEscapingUse(P->getOperandUse(2*ii));
+      for (unsigned ii = 0, ee = P->getNumIncomingValues(); ii != ee; ++ii) {
+        unsigned jj = PHINode::getOperandNumForIncomingValue(ii);
+        AA->addEscapingUse(P->getOperandUse(jj));
+      }
     }
   }
 
@@ -2149,8 +2151,11 @@ bool GVN::performPRE(Function &F) {
         // Because we have added a PHI-use of the pointer value, it has now
         // "escaped" from alias analysis' perspective.  We need to inform
         // AA of this.
-        for (unsigned ii = 0, ee = Phi->getNumIncomingValues(); ii != ee; ++ii)
-          VN.getAliasAnalysis()->addEscapingUse(Phi->getOperandUse(2*ii));
+        for (unsigned ii = 0, ee = Phi->getNumIncomingValues(); ii != ee;
+             ++ii) {
+          unsigned jj = PHINode::getOperandNumForIncomingValue(ii);
+          VN.getAliasAnalysis()->addEscapingUse(Phi->getOperandUse(jj));
+        }
         
         if (MD)
           MD->invalidateCachedPointerInfo(Phi);
diff --git a/llvm/lib/Transforms/Scalar/LoopRotation.cpp b/llvm/lib/Transforms/Scalar/LoopRotation.cpp
index 47dced37c3a..9fd0958fd4c 100644
--- a/llvm/lib/Transforms/Scalar/LoopRotation.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopRotation.cpp
@@ -220,7 +220,7 @@ bool LoopRotate::rotateLoop(Loop *L) {
   // For PHI nodes, the value available in OldPreHeader is just the
   // incoming value from OldPreHeader.
   for (; PHINode *PN = dyn_cast<PHINode>(I); ++I)
-    ValueMap[PN] = PN->getIncomingValue(PN->getBasicBlockIndex(OrigPreheader));
+    ValueMap[PN] = PN->getIncomingValueForBlock(OrigPreheader);
 
   // For the rest of the instructions, either hoist to the OrigPreheader if
   // possible or create a clone in the OldPreHeader if not.
diff --git a/llvm/lib/VMCore/AsmWriter.cpp b/llvm/lib/VMCore/AsmWriter.cpp
index e190beaa277..fff48674c61 100644
--- a/llvm/lib/VMCore/AsmWriter.cpp
+++ b/llvm/lib/VMCore/AsmWriter.cpp
@@ -1905,16 +1905,16 @@ void AssemblyWriter::printInstruction(const Instruction &I) {
       writeOperand(I.getOperand(i), true);
     }
     Out << ']';
-  } else if (isa<PHINode>(I)) {
+  } else if (const PHINode *PN = dyn_cast<PHINode>(&I)) {
     Out << ' ';
     TypePrinter.print(I.getType(), Out);
     Out << ' ';
 
-    for (unsigned op = 0, Eop = I.getNumOperands(); op < Eop; op += 2) {
+    for (unsigned op = 0, Eop = PN->getNumIncomingValues(); op < Eop; ++op) {
       if (op) Out << ", ";
       Out << "[ ";
-      writeOperand(I.getOperand(op  ), false); Out << ", ";
-      writeOperand(I.getOperand(op+1), false); Out << " ]";
+      writeOperand(PN->getIncomingValue(op), false); Out << ", ";
+      writeOperand(PN->getIncomingBlock(op), false); Out << " ]";
     }
   } else if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(&I)) {
     Out << ' ';
diff --git a/llvm/lib/VMCore/BasicBlock.cpp b/llvm/lib/VMCore/BasicBlock.cpp
index 955a0285b26..3f1a6a99b64 100644
--- a/llvm/lib/VMCore/BasicBlock.cpp
+++ b/llvm/lib/VMCore/BasicBlock.cpp
@@ -227,8 +227,8 @@ void BasicBlock::removePredecessor(BasicBlock *Pred,
 
       // If the PHI _HAD_ two uses, replace PHI node with its now *single* value
       if (max_idx == 2) {
-        if (PN->getOperand(0) != PN)
-          PN->replaceAllUsesWith(PN->getOperand(0));
+        if (PN->getIncomingValue(0) != PN)
+          PN->replaceAllUsesWith(PN->getIncomingValue(0));
         else
           // We are left with an infinite loop with no entries: kill the PHI.
           PN->replaceAllUsesWith(UndefValue::get(PN->getType()));
diff --git a/llvm/lib/VMCore/Verifier.cpp b/llvm/lib/VMCore/Verifier.cpp
index 139e0352301..e504016169c 100644
--- a/llvm/lib/VMCore/Verifier.cpp
+++ b/llvm/lib/VMCore/Verifier.cpp
@@ -1482,8 +1482,10 @@ void Verifier::visitInstruction(Instruction &I) {
         // PHI nodes differ from other nodes because they actually "use" the
         // value in the predecessor basic blocks they correspond to.
         BasicBlock *UseBlock = BB;
-        if (isa<PHINode>(I))
-          UseBlock = dyn_cast<BasicBlock>(I.getOperand(i+1));
+        if (PHINode *PN = dyn_cast<PHINode>(&I)) {
+          unsigned j = PHINode::getIncomingValueNumForOperand(i);
+          UseBlock = PN->getIncomingBlock(j);
+        }
         Assert2(UseBlock, "Invoke operand is PHI node with bad incoming-BB",
                 Op, &I);
 
@@ -1515,10 +1517,11 @@ void Verifier::visitInstruction(Instruction &I) {
                 return;
               }
         }
-      } else if (isa<PHINode>(I)) {
+      } else if (PHINode *PN = dyn_cast<PHINode>(&I)) {
         // PHI nodes are more difficult than other nodes because they actually
         // "use" the value in the predecessor basic blocks they correspond to.
-        BasicBlock *PredBB = dyn_cast<BasicBlock>(I.getOperand(i+1));
+        unsigned j = PHINode::getIncomingValueNumForOperand(i);
+        BasicBlock *PredBB = PN->getIncomingBlock(j);
         Assert2(PredBB && (DT->dominates(OpBlock, PredBB) ||
                            !DT->isReachableFromEntry(PredBB)),
                 "Instruction does not dominate all uses!", Op, &I);