block->addArguments({type, type}, SmallVector<Location, 2>(2, loc));
    auto add_op = builder.create<AddOp>(loc, block->getArgument(0),
                                        block->getArgument(1));
    builder.create<ReturnOp>(loc, add_op.getResult());
  }
};

class ConvertTensorScatterSubOp
    : public ConvertTensorScatterOp<ConvertTensorScatterSubOp,

<pre class="ebnf">
Expression = UnaryExpr | Expression binary_op Expression .
UnaryExpr  = PrimaryExpr | unary_op UnaryExpr .

binary_op  = "||" | "&amp;&amp;" | rel_op | add_op | mul_op .
rel_op     = "==" | "!=" | "&lt;" | "&lt;=" | ">" | ">=" .
add_op     = "+" | "-" | "|" | "^" .
mul_op     = "*" | "/" | "%" | "&lt;&lt;" | "&gt;&gt;" | "&amp;" | "&amp;^" .

unary_op   = "+" | "-" | "!" | "^" | "*" | "&amp;" | "&lt;-" .