vrs-without-perprimitive-or-screenspace-source

Status: shipped (Phase 8) — see CHANGELOG.

What it detects

A pixel-shader entry point that emits SV_ShadingRate but the source contains no upstream VRS source ([earlydepthstencil], per-primitive coarse-rate hint, or screen-space VRS image).

Why it matters on a GPU

PS-emitted VRS rates without an upstream source are silently ignored on most IHVs (Turing+, RDNA 2+, Battlemage). The shading-rate signal needs a combiner pair: per-pixel + per-primitive (or per-pixel + screen-space). A PS that emits a rate without a peer signal is dead code from the rasterizer's perspective.

Examples

Bad

struct PSOut { float4 c : SV_Target; uint r : SV_ShadingRate; };
PSOut ps_main() { PSOut o; o.r = 0; return o; }

Good

[earlydepthstencil]
struct PSOut { float4 c : SV_Target; uint r : SV_ShadingRate; };
PSOut ps_main() { PSOut o; o.r = 0; return o; }

Options

none

Fix availability

suggestion