Vector GEP - fixed a crash on InstSimplify Pass.

Vector GEP with mixed (vector and scalar) indices failed on the InstSimplify Pass when all indices are constants.

Differential revision http://reviews.llvm.org/D20149

llvm-svn: 269590

2 files changed, 25 insertions, 7 deletions

diff --git a/llvm/lib/IR/Constants.cpp b/llvm/lib/IR/Constants.cpp
index 5c568fa5f64..81832789063 100644
--- a/llvm/lib/IR/Constants.cpp
+++ b/llvm/lib/IR/Constants.cpp
@@ -1912,8 +1912,16 @@ Constant *ConstantExpr::getGetElementPtr(Type *Ty, Constant *C,
   assert(DestTy && "GEP indices invalid!");
   unsigned AS = C->getType()->getPointerAddressSpace();
   Type *ReqTy = DestTy->getPointerTo(AS);
-  if (VectorType *VecTy = dyn_cast<VectorType>(C->getType()))
-    ReqTy = VectorType::get(ReqTy, VecTy->getNumElements());
+
+  unsigned NumVecElts = 0;
+  if (C->getType()->isVectorTy())
+    NumVecElts = C->getType()->getVectorNumElements();
+  else for (auto Idx : Idxs)
+    if (Idx->getType()->isVectorTy())
+      NumVecElts = Idx->getType()->getVectorNumElements();
+
+  if (NumVecElts)
+    ReqTy = VectorType::get(ReqTy, NumVecElts);
 
   if (OnlyIfReducedTy == ReqTy)
     return nullptr;
@@ -1923,13 +1931,14 @@ Constant *ConstantExpr::getGetElementPtr(Type *Ty, Constant *C,
   ArgVec.reserve(1 + Idxs.size());
   ArgVec.push_back(C);
   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()) &&
+            Idxs[i]->getType()->getVectorNumElements() == NumVecElts) &&
            "getelementptr index type missmatch");
-    ArgVec.push_back(cast<Constant>(Idxs[i]));
+
+    Constant *Idx = cast<Constant>(Idxs[i]);
+    if (NumVecElts && !Idxs[i]->getType()->isVectorTy())
+      Idx = ConstantVector::getSplat(NumVecElts, Idx);
+    ArgVec.push_back(Idx);
   }
   const ConstantExprKeyType Key(Instruction::GetElementPtr, ArgVec, 0,
                                 InBounds ? GEPOperator::IsInBounds : 0, None,
diff --git a/llvm/test/Transforms/InstSimplify/vector_gep.ll b/llvm/test/Transforms/InstSimplify/vector_gep.ll
index 5c3062047c3..54887e99ee3 100644
--- a/llvm/test/Transforms/InstSimplify/vector_gep.ll
+++ b/llvm/test/Transforms/InstSimplify/vector_gep.ll
@@ -53,3 +53,12 @@ define <4 x i8*> @test5() {
 ; CHECK-LABEL: @test5
 ; CHECK-NEXT: ret <4 x i8*> getelementptr (i8, <4 x i8*> <i8* inttoptr (i64 1 to i8*), i8* inttoptr (i64 2 to i8*), i8* inttoptr (i64 3 to i8*), i8* inttoptr (i64 4 to i8*)>, <4 x i32> <i32 1, i32 1, i32 1, i32 1>)
 }
+
+@v = global [24 x [42 x [3 x i32]]] zeroinitializer, align 16
+
+define <16 x i32*> @test6() {
+; CHECK-LABEL: @test6
+; CHECK-NEXT: ret <16 x i32*> getelementptr ([24 x [42 x [3 x i32]]], [24 x [42 x [3 x i32]]]* @v, <16 x i64> zeroinitializer, <16 x i64> zeroinitializer, <16 x i64> <i64 0, i64 1, i64 2, i64 3, i64 4, i64 5, i64 6, i64 7, i64 8, i64 9, i64 10, i64 11, i64 12, i64 13, i64 14, i64 15>, <16 x i64> zeroinitializer)
+  %VectorGep = getelementptr [24 x [42 x [3 x i32]]], [24 x [42 x [3 x i32]]]* @v, i64 0, i64 0, <16 x i64> <i64 0, i64 1, i64 2, i64 3, i64 4, i64 5, i64 6, i64 7, i64 8, i64 9, i64 10, i64 11, i64 12, i64 13, i64 14, i64 15>, i64 0
+  ret <16 x i32*> %VectorGep
+}
\ No newline at end of file