reapply r148901 with a crucial fix.

"Introduce a new ConstantVector::getSplat constructor function to 
simplify a really common case."


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148924 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 59 insertions, 31 deletions

diff --git a/lib/VMCore/Constants.cpp b/lib/VMCore/Constants.cpp
index 6cb36bf..dd13ace 100644
--- a/lib/VMCore/Constants.cpp
+++ b/lib/VMCore/Constants.cpp
@@ -129,7 +129,7 @@ Constant *Constant::getIntegerValue(Type *Ty, const APInt &V) {
 
   // Broadcast a scalar to a vector, if necessary.
   if (VectorType *VTy = dyn_cast<VectorType>(Ty))
-    C = ConstantVector::get(std::vector<Constant *>(VTy->getNumElements(), C));
+    C = ConstantVector::getSplat(VTy->getNumElements(), C);
 
   return C;
 }
@@ -145,11 +145,9 @@ Constant *Constant::getAllOnesValue(Type *Ty) {
     return ConstantFP::get(Ty->getContext(), FL);
   }
 
-  SmallVector<Constant*, 16> Elts;
   VectorType *VTy = cast<VectorType>(Ty);
-  Elts.resize(VTy->getNumElements(), getAllOnesValue(VTy->getElementType()));
-  assert(Elts[0] && "Invalid AllOnes value!");
-  return cast<ConstantVector>(ConstantVector::get(Elts));
+  return ConstantVector::getSplat(VTy->getNumElements(),
+                                  getAllOnesValue(VTy->getElementType()));
 }
 
 void Constant::destroyConstantImpl() {
@@ -394,9 +392,8 @@ Constant *ConstantInt::getTrue(Type *Ty) {
   }
   assert(VTy->getElementType()->isIntegerTy(1) &&
          "True must be vector of i1 or i1.");
-  SmallVector<Constant*, 16> Splat(VTy->getNumElements(),
-                                   ConstantInt::getTrue(Ty->getContext()));
-  return ConstantVector::get(Splat);
+  return ConstantVector::getSplat(VTy->getNumElements(),
+                                  ConstantInt::getTrue(Ty->getContext()));
 }
 
 Constant *ConstantInt::getFalse(Type *Ty) {
@@ -407,9 +404,8 @@ Constant *ConstantInt::getFalse(Type *Ty) {
   }
   assert(VTy->getElementType()->isIntegerTy(1) &&
          "False must be vector of i1 or i1.");
-  SmallVector<Constant*, 16> Splat(VTy->getNumElements(),
-                                   ConstantInt::getFalse(Ty->getContext()));
-  return ConstantVector::get(Splat);
+  return ConstantVector::getSplat(VTy->getNumElements(),
+                                  ConstantInt::getFalse(Ty->getContext()));
 }
 
 
@@ -433,8 +429,7 @@ Constant *ConstantInt::get(Type *Ty, uint64_t V, bool isSigned) {
 
   // For vectors, broadcast the value.
   if (VectorType *VTy = dyn_cast<VectorType>(Ty))
-    return ConstantVector::get(SmallVector<Constant*,
-                                           16>(VTy->getNumElements(), C));
+    return ConstantVector::getSplat(VTy->getNumElements(), C);
 
   return C;
 }
@@ -459,8 +454,7 @@ Constant *ConstantInt::get(Type* Ty, const APInt& V) {
 
   // For vectors, broadcast the value.
   if (VectorType *VTy = dyn_cast<VectorType>(Ty))
-    return ConstantVector::get(
-      SmallVector<Constant *, 16>(VTy->getNumElements(), C));
+    return ConstantVector::getSplat(VTy->getNumElements(), C);
 
   return C;
 }
@@ -506,8 +500,7 @@ Constant *ConstantFP::get(Type* Ty, double V) {
 
   // For vectors, broadcast the value.
   if (VectorType *VTy = dyn_cast<VectorType>(Ty))
-    return ConstantVector::get(
-      SmallVector<Constant *, 16>(VTy->getNumElements(), C));
+    return ConstantVector::getSplat(VTy->getNumElements(), C);
 
   return C;
 }
@@ -521,31 +514,28 @@ Constant *ConstantFP::get(Type* Ty, StringRef Str) {
 
   // For vectors, broadcast the value.
   if (VectorType *VTy = dyn_cast<VectorType>(Ty))
-    return ConstantVector::get(
-      SmallVector<Constant *, 16>(VTy->getNumElements(), C));
+    return ConstantVector::getSplat(VTy->getNumElements(), C);
 
   return C; 
 }
 
 
-ConstantFP* ConstantFP::getNegativeZero(Type* Ty) {
+ConstantFP *ConstantFP::getNegativeZero(Type *Ty) {
   LLVMContext &Context = Ty->getContext();
-  APFloat apf = cast <ConstantFP>(Constant::getNullValue(Ty))->getValueAPF();
+  APFloat apf = cast<ConstantFP>(Constant::getNullValue(Ty))->getValueAPF();
   apf.changeSign();
   return get(Context, apf);
 }
 
 
-Constant *ConstantFP::getZeroValueForNegation(Type* Ty) {
-  if (VectorType *PTy = dyn_cast<VectorType>(Ty))
-    if (PTy->getElementType()->isFloatingPointTy()) {
-      SmallVector<Constant*, 16> zeros(PTy->getNumElements(),
-                           getNegativeZero(PTy->getElementType()));
-      return ConstantVector::get(zeros);
-    }
-
-  if (Ty->isFloatingPointTy()) 
-    return getNegativeZero(Ty);
+Constant *ConstantFP::getZeroValueForNegation(Type *Ty) {
+  Type *ScalarTy = Ty->getScalarType();
+  if (ScalarTy->isFloatingPointTy()) {
+    Constant *C = getNegativeZero(ScalarTy);
+    if (VectorType *VTy = dyn_cast<VectorType>(Ty))
+      return ConstantVector::getSplat(VTy->getNumElements(), C);
+    return C;
+  }
 
   return Constant::getNullValue(Ty);
 }
@@ -818,6 +808,12 @@ Constant *ConstantVector::get(ArrayRef<Constant*> V) {
   return pImpl->VectorConstants.getOrCreate(T, V);
 }
 
+Constant *ConstantVector::getSplat(unsigned NumElts, Constant *V) {
+  SmallVector<Constant*, 32> Elts(NumElts, V);
+  return get(Elts);
+}
+
+
 // Utility function for determining if a ConstantExpr is a CastOp or not. This
 // can't be inline because we don't want to #include Instruction.h into
 // Constant.h
@@ -2196,6 +2192,38 @@ Constant *ConstantDataVector::get(LLVMContext &Context, ArrayRef<double> Elts) {
   return getImpl(StringRef((char*)Elts.data(), Elts.size()*8), Ty);
 }
 
+Constant *ConstantDataVector::getSplat(unsigned NumElts, Constant *V) {
+  assert(isElementTypeCompatible(V->getType()) &&
+         "Element type not compatible with ConstantData");
+  if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
+    if (CI->getType()->isIntegerTy(8)) {
+      SmallVector<uint8_t, 16> Elts(NumElts, CI->getZExtValue());
+      return get(V->getContext(), Elts);
+    }
+    if (CI->getType()->isIntegerTy(16)) {
+      SmallVector<uint16_t, 16> Elts(NumElts, CI->getZExtValue());
+      return get(V->getContext(), Elts);
+    }
+    if (CI->getType()->isIntegerTy(32)) {
+      SmallVector<uint32_t, 16> Elts(NumElts, CI->getZExtValue());
+      return get(V->getContext(), Elts);
+    }
+    assert(CI->getType()->isIntegerTy(64) && "Unsupported ConstantData type");
+    SmallVector<uint64_t, 16> Elts(NumElts, CI->getZExtValue());
+    return get(V->getContext(), Elts);
+  }
+
+  ConstantFP *CFP = cast<ConstantFP>(V);
+  if (CFP->getType()->isFloatTy()) {
+    SmallVector<float, 16> Elts(NumElts, CFP->getValueAPF().convertToFloat());
+    return get(V->getContext(), Elts);
+  }
+  assert(CFP->getType()->isDoubleTy() && "Unsupported ConstantData type");
+  SmallVector<double, 16> Elts(NumElts, CFP->getValueAPF().convertToDouble());
+  return get(V->getContext(), Elts);
+}
+
+
 /// getElementAsInteger - If this is a sequential container of integers (of
 /// any size), return the specified element in the low bits of a uint64_t.
 uint64_t ConstantDataSequential::getElementAsInteger(unsigned Elt) const {