Relax the restrictions on vector of pointer types, and vector getelementptr.

Previously in a vector of pointers, the pointer couldn't be any pointer type,
it had to be a pointer to an integer or floating point type.  This is a hassle
for dragonegg because the GCC vectorizer happily produces vectors of pointers
where the pointer is a pointer to a struct or whatever.  Vector getelementptr
was restricted to just one index, but now that vectors of pointers can have
any pointer type it is more natural to allow arbitrary vector getelementptrs.
There is however the issue of struct GEPs, where if each lane chose different
struct fields then from that point on each lane will be working down into
unrelated types.  This seems like too much pain for too little gain, so when
you have a vector struct index all the elements are required to be the same.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167828 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 38 insertions, 3 deletions

diff --git a/lib/VMCore/Constants.cpp b/lib/VMCore/Constants.cpp
index a4e21e16b3..f96fb1d401 100644
--- a/lib/VMCore/Constants.cpp
+++ b/lib/VMCore/Constants.cpp
@@ -1213,6 +1213,19 @@ void ConstantVector::destroyConstant() {
   destroyConstantImpl();
 }
 
+/// getSplatValue - If this is a splat vector constant, meaning that all of
+/// the elements have the same value, return that value. Otherwise return 0.
+Constant *Constant::getSplatValue() const {
+  assert(this->getType()->isVectorTy() && "Only valid for vectors!");
+  if (isa<ConstantAggregateZero>(this))
+    return getNullValue(this->getType()->getVectorElementType());
+  if (const ConstantDataVector *CV = dyn_cast<ConstantDataVector>(this))
+    return CV->getSplatValue();
+  if (const ConstantVector *CV = dyn_cast<ConstantVector>(this))
+    return CV->getSplatValue();
+  return 0;
+}
+
 /// getSplatValue - If this is a splat constant, where all of the
 /// elements have the same value, return that value. Otherwise return null.
 Constant *ConstantVector::getSplatValue() const {
@@ -1225,6 +1238,18 @@ Constant *ConstantVector::getSplatValue() const {
   return Elt;
 }
 
+/// If C is a constant integer then return its value, otherwise C must be a
+/// vector of constant integers, all equal, and the common value is returned.
+const APInt &Constant::getUniqueInteger() const {
+  if (const ConstantInt *CI = dyn_cast<ConstantInt>(this))
+    return CI->getValue();
+  assert(this->getSplatValue() && "Doesn't contain a unique integer!");
+  const Constant *C = this->getAggregateElement(0U);
+  assert(C && isa<ConstantInt>(C) && "Not a vector of numbers!");
+  return cast<ConstantInt>(C)->getValue();
+}
+
+
 //---- ConstantPointerNull::get() implementation.
 //
 
@@ -1739,6 +1764,9 @@ Constant *ConstantExpr::getSelect(Constant *C, Constant *V1, Constant *V2) {
 
 Constant *ConstantExpr::getGetElementPtr(Constant *C, ArrayRef<Value *> Idxs,
                                          bool InBounds) {
+  assert(C->getType()->isPtrOrPtrVectorTy() &&
+         "Non-pointer type for constant GetElementPtr expression");
+
   if (Constant *FC = ConstantFoldGetElementPtr(C, InBounds, Idxs))
     return FC;          // Fold a few common cases.
 
@@ -1747,15 +1775,22 @@ Constant *ConstantExpr::getGetElementPtr(Constant *C, ArrayRef<Value *> Idxs,
   assert(Ty && "GEP indices invalid!");
   unsigned AS = C->getType()->getPointerAddressSpace();
   Type *ReqTy = Ty->getPointerTo(AS);
+  if (VectorType *VecTy = dyn_cast<VectorType>(C->getType()))
+    ReqTy = VectorType::get(ReqTy, VecTy->getNumElements());
 
-  assert(C->getType()->isPointerTy() &&
-         "Non-pointer type for constant GetElementPtr expression");
   // Look up the constant in the table first to ensure uniqueness
   std::vector<Constant*> ArgVec;
   ArgVec.reserve(1 + Idxs.size());
   ArgVec.push_back(C);
-  for (unsigned i = 0, e = Idxs.size(); i != e; ++i)
+  for (unsigned i = 0, e = Idxs.size(); i != e; ++i) {
+    assert(Idxs[i]->getType()->isVectorTy() == ReqTy->isVectorTy() &&
+           "getelementptr index type missmatch");
+    assert((!Idxs[i]->getType()->isVectorTy() ||
+            ReqTy->getVectorNumElements() ==
+            Idxs[i]->getType()->getVectorNumElements()) &&
+           "getelementptr index type missmatch");
     ArgVec.push_back(cast<Constant>(Idxs[i]));
+  }
   const ExprMapKeyType Key(Instruction::GetElementPtr, ArgVec, 0,
                            InBounds ? GEPOperator::IsInBounds : 0);