- // RHS must be a constant, we must be undef, constant, or notconstant.
- assert(!isConstantRange() &&
- "Constant and ConstantRange cannot be merged.");
+ // RHS must be a constant, we must be constantrange,
+ // undef, constant, or notconstant.
+ if (isConstantRange()) {
+ // FIXME: This could be made more precise.
+ return markOverdefined();
+ }