Provide a replication operator for arrays/bits

[mikex-oss]

What's hard to do? (limit 100 words)

Create arrays and bit vectors with replicated patterns. SystemVerilog provides the replication operator which works on both, so you can do stuff like:

int n[1:2][1:6] = '{2{'{3{4, 5}}}};

which is equivalent to:

'{'{4,5,4,5,4,5},'{4,5,4,5,4,5}}

Similarly, you can do:

{4{4'b1010, 4'b1001}}

which is equivalent to

32'b10101001101010011010100110101001

Current best alternative workaround (limit 100 words)

You could write for loops to do update and bit_slice_update. Or just copy-paste manually.

Your view of the "best case XLS enhancement" (limit 100 words)

Support this in DSLX.

[cdleary]

On the "workaround" -- we can add a stdlib function to do this before adding a builtin, right?

[mikex-oss]

I think that makes sense, with the main downside being verbosity...particularly without type generics, you'd have, for example, std::array_repl and std::bits_repl.