On Wed, 12 Nov 2025 20:11:06 GMT, Paul Sandoz <[email protected]> wrote:

> The basic type codes are declared and shared across Java and HotSpot - it's 
> used in `LaneType`. Can we pass a single argument that is the basic type 
> instead of two arguments. HotSpot should know from the basic type what the 
> carrier class and also what the operation type without it being explicitly 
> told, since presumably it knew the inverse - the basic type from the element 
> class.

Hi @PaulSandoz, T_HALFFLOAT used in LaneType is mainly used for differentiation 
of various cache keys used by conversion operation lookups. In principle, we 
can extend VM to acknowledge this new custom basic type on the lines of 
T_METADATA / T_ADDRESS; its scope for now will be restricted to VectorSupport. 
We can gradually expose this to C2 type, such that TypeVect for all Float16 
VectorIR uses T_HALFFLOAT as its basic type; currently, we use T_SHORT as the 
lane type. Let me know if this looks reasonable

-------------

PR Comment: https://git.openjdk.org/jdk/pull/28002#issuecomment-3526715585

Reply via email to