use Constant::getAggregateElement to simplify a bunch of code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148934 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 58 insertions, 179 deletions

diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index 43b3af2..6a49e6d 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -311,30 +311,20 @@ static bool ReadDataFromGlobal(Constant *C, uint64_t ByteOffset,
     // not reached.
   }
 
-  if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) {
-    uint64_t EltSize = TD.getTypeAllocSize(CA->getType()->getElementType());
+  if (isa<ConstantArray>(C) || isa<ConstantVector>(C) ||
+      isa<ConstantDataSequential>(C)) {
+    Type *EltTy = cast<SequentialType>(C->getType())->getElementType();
+    uint64_t EltSize = TD.getTypeAllocSize(EltTy);
     uint64_t Index = ByteOffset / EltSize;
     uint64_t Offset = ByteOffset - Index * EltSize;
-    for (; Index != CA->getType()->getNumElements(); ++Index) {
-      if (!ReadDataFromGlobal(CA->getOperand(Index), Offset, CurPtr,
-                              BytesLeft, TD))
-        return false;
-      if (EltSize >= BytesLeft)
-        return true;
-      
-      Offset = 0;
-      BytesLeft -= EltSize;
-      CurPtr += EltSize;
-    }
-    return true;
-  }
-  
-  if (ConstantVector *CV = dyn_cast<ConstantVector>(C)) {
-    uint64_t EltSize = TD.getTypeAllocSize(CV->getType()->getElementType());
-    uint64_t Index = ByteOffset / EltSize;
-    uint64_t Offset = ByteOffset - Index * EltSize;
-    for (; Index != CV->getType()->getNumElements(); ++Index) {
-      if (!ReadDataFromGlobal(CV->getOperand(Index), Offset, CurPtr,
+    uint64_t NumElts;
+    if (ArrayType *AT = dyn_cast<ArrayType>(C->getType()))
+      NumElts = AT->getNumElements();
+    else
+      NumElts = cast<VectorType>(C->getType())->getNumElements();
+    
+    for (; Index != NumElts; ++Index) {
+      if (!ReadDataFromGlobal(C->getAggregateElement(Index), Offset, CurPtr,
                               BytesLeft, TD))
         return false;
       if (EltSize >= BytesLeft)
@@ -346,30 +336,12 @@ static bool ReadDataFromGlobal(Constant *C, uint64_t ByteOffset,
     }
     return true;
   }
-  
-  if (ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(C)) {
-    uint64_t EltSize = CDS->getElementByteSize();
-    uint64_t Index = ByteOffset / EltSize;    
-    uint64_t Offset = ByteOffset - Index * EltSize;
-    for (unsigned e = CDS->getNumElements(); Index != e; ++Index) {
-      if (!ReadDataFromGlobal(CDS->getElementAsConstant(Index), Offset, CurPtr,
-                              BytesLeft, TD))
-        return false;
-      if (EltSize >= BytesLeft)
-        return true;
       
-      Offset = 0;
-      BytesLeft -= EltSize;
-      CurPtr += EltSize;
-    }
-    return true;
-  }
-    
   if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
     if (CE->getOpcode() == Instruction::IntToPtr &&
         CE->getOperand(0)->getType() == TD.getIntPtrType(CE->getContext())) 
-        return ReadDataFromGlobal(CE->getOperand(0), ByteOffset, CurPtr, 
-                                  BytesLeft, TD);
+      return ReadDataFromGlobal(CE->getOperand(0), ByteOffset, CurPtr, 
+                                BytesLeft, TD);
   }
 
   // Otherwise, unknown initializer type.
@@ -1010,11 +982,14 @@ Constant *llvm::ConstantFoldLoadThroughGEPConstantExpr(Constant *C,
                                                        ConstantExpr *CE) {
   if (!CE->getOperand(1)->isNullValue())
     return 0;  // Do not allow stepping over the value!
-  
-  SmallVector<Constant*, 8> Indices(CE->getNumOperands()-2);
-  for (unsigned i = 2, e = CE->getNumOperands(); i != e; ++i)
-    Indices[i-2] = CE->getOperand(i);
-  return ConstantFoldLoadThroughGEPIndices(C, Indices);
+
+  // Loop over all of the operands, tracking down which value we are
+  // addressing.
+  for (unsigned i = 2, e = CE->getNumOperands(); i != e; ++i) {
+    C = C->getAggregateElement(CE->getOperand(i));
+    if (C == 0) return 0;
+  }
+  return C;
 }
 
 /// ConstantFoldLoadThroughGEPIndices - Given a constant and getelementptr
@@ -1026,32 +1001,8 @@ Constant *llvm::ConstantFoldLoadThroughGEPIndices(Constant *C,
   // Loop over all of the operands, tracking down which value we are
   // addressing.
   for (unsigned i = 0, e = Indices.size(); i != e; ++i) {
-    ConstantInt *Idx = dyn_cast<ConstantInt>(Indices[i]);
-    if (Idx == 0) return 0;
-    
-    uint64_t IdxVal = Idx->getZExtValue();
-    
-    if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) {
-      C = CS->getOperand(IdxVal);
-    } else if (ConstantAggregateZero *CAZ = dyn_cast<ConstantAggregateZero>(C)){
-      C = CAZ->getElementValue(Idx);
-    } else if (UndefValue *UV = dyn_cast<UndefValue>(C)) {
-      C = UV->getElementValue(Idx);
-    } else if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) {
-      if (IdxVal >= CA->getType()->getNumElements())
-        return 0;
-      C = CA->getOperand(IdxVal);
-    } else if (ConstantDataSequential *CDS=dyn_cast<ConstantDataSequential>(C)){
-      if (IdxVal >= CDS->getNumElements())
-        return 0;
-      C = CDS->getElementAsConstant(IdxVal);
-    } else if (ConstantVector *CV = dyn_cast<ConstantVector>(C)) {
-      if (IdxVal >= CV->getType()->getNumElements())
-        return 0;
-      C = CV->getOperand(IdxVal);
-    } else {
-      return 0;
-    }
+    C = C->getAggregateElement(Indices[i]);
+    if (C == 0) return 0;
   }
   return C;
 }
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index ca55fcb..21008a1 100644
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -1493,19 +1493,12 @@ Value *llvm::FindInsertedValue(Value *V, ArrayRef<unsigned> idx_range,
          "Not looking at a struct or array?");
   assert(ExtractValueInst::getIndexedType(V->getType(), idx_range) &&
          "Invalid indices for type?");
-  CompositeType *PTy = cast<CompositeType>(V->getType());
-
-  if (isa<UndefValue>(V))
-    return UndefValue::get(ExtractValueInst::getIndexedType(PTy, idx_range));
-  if (isa<ConstantAggregateZero>(V))
-    return Constant::getNullValue(ExtractValueInst::getIndexedType(PTy, 
-                                                                  idx_range));
-  if (isa<ConstantArray>(V) || isa<ConstantStruct>(V))
-    // Recursively process this constant
-    return FindInsertedValue(cast<Constant>(V)->getOperand(idx_range[0]),
-                             idx_range.slice(1), InsertBefore);
-  if (ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
-    return CDS->getElementAsConstant(idx_range[0]);
+
+  if (Constant *C = dyn_cast<Constant>(V)) {
+    C = C->getAggregateElement(idx_range[0]);
+    if (C == 0) return 0;
+    return FindInsertedValue(C, idx_range.slice(1), InsertBefore);
+  }
     
   if (InsertValueInst *I = dyn_cast<InsertValueInst>(V)) {
     // Loop the indices for the insertvalue instruction in parallel with the
diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp
index 563aed5..60fa9a7 100644
--- a/lib/Linker/LinkModules.cpp
+++ b/lib/Linker/LinkModules.cpp
@@ -844,21 +844,10 @@ bool ModuleLinker::linkAliasProto(GlobalAlias *SGA) {
 }
 
 static void getArrayElements(Constant *C, SmallVectorImpl<Constant*> &Dest) {
-  if (ConstantArray *I = dyn_cast<ConstantArray>(C)) {
-    for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
-      Dest.push_back(I->getOperand(i));
-    return;
-  }
-  
-  if (ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(C)) {
-    for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i)
-      Dest.push_back(CDS->getElementAsConstant(i));
-    return;
-  }
-  
-  ConstantAggregateZero *CAZ = cast<ConstantAggregateZero>(C);
-  Dest.append(cast<ArrayType>(C->getType())->getNumElements(),
-              CAZ->getSequentialElement());
+  unsigned NumElements = cast<ArrayType>(C->getType())->getNumElements();
+
+  for (unsigned i = 0; i != NumElements; ++i)
+    Dest.push_back(C->getAggregateElement(i));
 }
                              
 void ModuleLinker::linkAppendingVarInit(const AppendingVarInfo &AVI) {
diff --git a/lib/Transforms/IPO/GlobalOpt.cpp b/lib/Transforms/IPO/GlobalOpt.cpp
index 2926508..6e8b434 100644
--- a/lib/Transforms/IPO/GlobalOpt.cpp
+++ b/lib/Transforms/IPO/GlobalOpt.cpp
@@ -276,38 +276,6 @@ static bool AnalyzeGlobal(const Value *V, GlobalStatus &GS,
   return false;
 }
 
-static Constant *getAggregateConstantElement(Constant *Agg, Constant *Idx) {
-  ConstantInt *CI = dyn_cast<ConstantInt>(Idx);
-  if (!CI) return 0;
-  unsigned IdxV = CI->getZExtValue();
-
-  if (ConstantStruct *CS = dyn_cast<ConstantStruct>(Agg)) {
-    if (IdxV < CS->getNumOperands()) return CS->getOperand(IdxV);
-  } else if (ConstantArray *CA = dyn_cast<ConstantArray>(Agg)) {
-    if (IdxV < CA->getNumOperands()) return CA->getOperand(IdxV);
-  } else if (ConstantVector *CP = dyn_cast<ConstantVector>(Agg)) {
-    if (IdxV < CP->getNumOperands()) return CP->getOperand(IdxV);
-  } else if (isa<ConstantAggregateZero>(Agg)) {
-    if (StructType *STy = dyn_cast<StructType>(Agg->getType())) {
-      if (IdxV < STy->getNumElements())
-        return Constant::getNullValue(STy->getElementType(IdxV));
-    } else if (SequentialType *STy =
-               dyn_cast<SequentialType>(Agg->getType())) {
-      return Constant::getNullValue(STy->getElementType());
-    }
-  } else if (isa<UndefValue>(Agg)) {
-    if (StructType *STy = dyn_cast<StructType>(Agg->getType())) {
-      if (IdxV < STy->getNumElements())
-        return UndefValue::get(STy->getElementType(IdxV));
-    } else if (SequentialType *STy =
-               dyn_cast<SequentialType>(Agg->getType())) {
-      return UndefValue::get(STy->getElementType());
-    }
-  }
-  return 0;
-}
-
-
 /// CleanupConstantGlobalUsers - We just marked GV constant.  Loop over all
 /// users of the global, cleaning up the obvious ones.  This is largely just a
 /// quick scan over the use list to clean up the easy and obvious cruft.  This
@@ -520,8 +488,7 @@ static GlobalVariable *SRAGlobal(GlobalVariable *GV, const TargetData &TD) {
     NewGlobals.reserve(STy->getNumElements());
     const StructLayout &Layout = *TD.getStructLayout(STy);
     for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
-      Constant *In = getAggregateConstantElement(Init,
-                    ConstantInt::get(Type::getInt32Ty(STy->getContext()), i));
+      Constant *In = Init->getAggregateElement(i);
       assert(In && "Couldn't get element of initializer?");
       GlobalVariable *NGV = new GlobalVariable(STy->getElementType(i), false,
                                                GlobalVariable::InternalLinkage,
@@ -553,8 +520,7 @@ static GlobalVariable *SRAGlobal(GlobalVariable *GV, const TargetData &TD) {
     uint64_t EltSize = TD.getTypeAllocSize(STy->getElementType());
     unsigned EltAlign = TD.getABITypeAlignment(STy->getElementType());
     for (unsigned i = 0, e = NumElements; i != e; ++i) {
-      Constant *In = getAggregateConstantElement(Init,
-                    ConstantInt::get(Type::getInt32Ty(Init->getContext()), i));
+      Constant *In = Init->getAggregateElement(i);
       assert(In && "Couldn't get element of initializer?");
 
       GlobalVariable *NGV = new GlobalVariable(STy->getElementType(), false,
diff --git a/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp b/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
index 7b1617d..6873d15 100644
--- a/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
+++ b/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
@@ -834,59 +834,39 @@ Value *InstCombiner::SimplifyDemandedVectorElts(Value *V, APInt DemandedElts,
   }
 
   UndefElts = 0;
-  if (ConstantVector *CV = dyn_cast<ConstantVector>(V)) {
+  
+  // Handle ConstantAggregateZero, ConstantVector, ConstantDataSequential.
+  if (Constant *C = dyn_cast<Constant>(V)) {
+    // Check if this is identity. If so, return 0 since we are not simplifying
+    // anything.
+    if (DemandedElts.isAllOnesValue())
+      return 0;
+
     Type *EltTy = cast<VectorType>(V->getType())->getElementType();
     Constant *Undef = UndefValue::get(EltTy);
-
-    std::vector<Constant*> Elts;
-    for (unsigned i = 0; i != VWidth; ++i)
+    
+    SmallVector<Constant*, 16> Elts;
+    for (unsigned i = 0; i != VWidth; ++i) {
       if (!DemandedElts[i]) {   // If not demanded, set to undef.
         Elts.push_back(Undef);
         UndefElts.setBit(i);
-      } else if (isa<UndefValue>(CV->getOperand(i))) {   // Already undef.
+        continue;
+      }
+      
+      Constant *Elt = C->getAggregateElement(i);
+      if (Elt == 0) return 0;
+      
+      if (isa<UndefValue>(Elt)) {   // Already undef.
         Elts.push_back(Undef);
         UndefElts.setBit(i);
       } else {                               // Otherwise, defined.
-        Elts.push_back(CV->getOperand(i));
+        Elts.push_back(Elt);
       }
-
+    }
+    
     // If we changed the constant, return it.
     Constant *NewCV = ConstantVector::get(Elts);
-    return NewCV != CV ? NewCV : 0;
-  }
-  
-  if (ConstantDataVector *CDV = dyn_cast<ConstantDataVector>(V)) {
-    // Check if this is identity. If so, return 0 since we are not simplifying
-    // anything.
-    if (DemandedElts.isAllOnesValue())
-      return 0;
-
-    // Simplify to a ConstantVector where the non-demanded elements are undef.
-    Constant *Undef = UndefValue::get(CDV->getElementType());
-    
-    SmallVector<Constant*, 16> Elts;
-    for (unsigned i = 0; i != VWidth; ++i)
-      Elts.push_back(DemandedElts[i] ? CDV->getElementAsConstant(i) : Undef);
-    UndefElts = DemandedElts ^ EltMask;
-    return ConstantVector::get(Elts);
-
-  }
-  
-  if (ConstantAggregateZero *CAZ = dyn_cast<ConstantAggregateZero>(V)) {
-    // Check if this is identity. If so, return 0 since we are not simplifying
-    // anything.
-    if (DemandedElts.isAllOnesValue())
-      return 0;
-    
-    // Simplify the CAZ to a ConstantVector where the non-demanded elements are
-    // set to undef.
-    Constant *Zero = CAZ->getSequentialElement();
-    Constant *Undef = UndefValue::get(Zero->getType());
-    SmallVector<Constant*, 16> Elts;
-    for (unsigned i = 0; i != VWidth; ++i)
-      Elts.push_back(DemandedElts[i] ? Zero : Undef);
-    UndefElts = DemandedElts ^ EltMask;
-    return ConstantVector::get(Elts);
+    return NewCV != C ? NewCV : 0;
   }
   
   // Limit search depth.