On 3/13/25 2:04 PM, Richard Biener wrote:
I think this is done by convert_vector_to_array_for_subscript in c-common/, note that this handles lvalue conversion as well which means it will not work in lvalue context where you'd possibly want sth like a TARGET_EXPR <D.1234, .VEC_CONVERT (vector)> but then the caller needs to assign D.1234 to 'vector' with a conversion back. This is going to be a bit difficult to deal with given the parser structure.
This is precisely the issue I ran into.
Indexing bit-precision mask vectors really breaks the assumption of convert_vector_to_array_for_subscript that there is an array type that is layout-compatible to the vector. So we'd need to handle this situation upthread somehow. The "cheap" way out would be to use .VEC_SET and .VEC_EXTRACT temporarily (expansion relies on the optabs to be presnet) and gimplify those away.
Thanks for the reviews - I'll try .VEC_SET and .VEC_EXTRACT. Thanks, Tejas.
