[ExecutionEngine] Fix GEP type

Fix bug introduced in 2c68ecc, the GEP type was off-by-ptr. Apparently I didn't run the MLIR tests.

Author: nikic

mlir/lib/ExecutionEngine/ExecutionEngine.cpp

@@ -180,7 +180,7 @@ static void packFunctionArguments(Module *module) {
  llvm::Value *argIndex = llvm::Constant::getIntegerValue(
  builder.getInt64Ty(), APInt(64, indexedArg.index()));
  llvm::Value *argPtrPtr = builder.CreateGEP(
- builder.getInt8Ty(), argList, argIndex);
+ builder.getInt8PtrTy(), argList, argIndex);
  llvm::Value *argPtr = builder.CreateLoad(builder.getInt8PtrTy(),
  argPtrPtr);
  llvm::Type *argTy = indexedArg.value().getType();
@@ -197,7 +197,7 @@ static void packFunctionArguments(Module *module) {
  llvm::Value *retIndex = llvm::Constant::getIntegerValue(
  builder.getInt64Ty(), APInt(64, llvm::size(func.args())));
  llvm::Value *retPtrPtr =
- builder.CreateGEP(builder.getInt8Ty(), argList, retIndex);
+ builder.CreateGEP(builder.getInt8PtrTy(), argList, retIndex);
  llvm::Value *retPtr = builder.CreateLoad(builder.getInt8PtrTy(),
  retPtrPtr);
  retPtr = builder.CreateBitCast(retPtr, result->getType()->getPointerTo());