D139 - The shader target is RDNA2, keyed by name

Status: decided Date: 2026-09-26

The shader subsystem targets the RDNA2-derived GPU of the current hardware generation. Supported, blocked and dispatched instructions are keyed by name, resolved once per instruction; an opcode with no recorded name is refused. Names come from the generators, merged with a conflict check.

Why: opcode numbers move between generations, and a list of numbers aimed at another generation binds silently to whatever occupies them. Names mostly survive a retarget, and those that do not arrive as an exact list of what needs attention.

Rejected:

• Family and opcode pairs: silent misbinding on retarget.
• Deriving widths from opcode arithmetic: an ordering that holds by coincidence.