add assertions

Author: fabianmcg

mlir/include/mlir/Dialect/Arith/IR/Arith.h

@@ -155,7 +155,9 @@ Value getReductionOp(AtomicRMWKind op, OpBuilder &builder, Location loc,
 
 arith::CmpIPredicate invertPredicate(arith::CmpIPredicate pred);
 
-/// Creates an `arith.constant` operation with a zero value of type `type`.
+/// Creates an `arith.constant` operation with a zero value of type `type`. This
+/// method asserts if `type` is invalid for representing zero with
+/// `arith.constant`.
 Value getZeroConstant(OpBuilder &builder, Location loc, Type type);
 } // namespace arith
 } // namespace mlir

mlir/lib/Dialect/Arith/IR/ArithOps.cpp

@@ -294,7 +294,12 @@ bool arith::ConstantIndexOp::classof(Operation *op) {
 
 Value mlir::arith::getZeroConstant(OpBuilder &builder, Location loc,
                                    Type type) {
-  return builder.create<arith::ConstantOp>(loc, builder.getZeroAttr(type));
+  // TODO: Incorporate this check to `FloatAttr::get*`.
+  assert(!isa<Float8E8M0FNUType>(getElementTypeOrSelf(type)) &&
+         "type doesn't have a zero representation");
+  TypedAttr zeroAttr = builder.getZeroAttr(type);
+  assert(zeroAttr && "unsupported type for zero attribute");
+  return builder.create<arith::ConstantOp>(loc, zeroAttr);
 }
 
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