Fix crash from r158529 on Bullet.

Dynamic GEPs created by SROA needed to insert extra "i32 0"
operands to index through structs and arrays to get to the
vector being indexed.

llvm-svn: 158590

1 files changed, 10 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp b/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp
index 9fc4164cc0e..bc428802e89 100644
--- a/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp
+++ b/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp
@@ -2011,8 +2011,17 @@ void SROA::RewriteGEP(GetElementPtrInst *GEPI, AllocaInst *AI, uint64_t Offset,
     uint64_t EltIdx = FindElementAndOffset(T, EltOffset, IdxTy);
     NewArgs.push_back(ConstantInt::get(IdxTy, EltIdx));
   }
-  if (NonConstantIdx)
+  if (NonConstantIdx) {
+    Type* GepTy = T;
+    // This GEP has a dynamic index.  We need to add "i32 0" to index through
+    // any structs or arrays in the original type until we get to the vector
+    // to index.
+    while (!isa<VectorType>(GepTy)) {
+      NewArgs.push_back(Constant::getNullValue(i32Ty));
+      GepTy = cast<CompositeType>(GepTy)->getTypeAtIndex(0U);
+    }
     NewArgs.push_back(NonConstantIdx);
+  }
   Instruction *Val = NewElts[Idx];
   if (NewArgs.size() > 1) {
     Val = GetElementPtrInst::CreateInBounds(Val, NewArgs, "", GEPI);