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wavesize-range-disordered

Status: stub. The full-length analysis is queued for a v1.0.x patch release per ADR 0018, section 5, criterion #6. The companion rule page at docs/rules/wavesize-range-disordered.md contains the canonical detection logic + GPU reasoning.

TL;DR

[WaveSize] is the contract between the shader author and the compiler about which wave widths the shader is willing to run on. The compiler uses the bounds to pick an instruction-selection strategy (RDNA 1/2/3 can run wave32 or wave64 depending on the kernel; NVIDIA Turing/Ada is fixed at wave32; Intel Xe-HPG runs wave8/16/32 depending on register pressure). When the bounds are well-ordered, the runtime picks an in-range wave size at dispatch time and the shader runs as designed.

What the rule fires on

A [WaveSize(min, preferred, max)] or [WaveSize(min, max)] attribute whose constant arguments are not in non-decreasing order. The SM 6.8 attribute requires min <= preferred <= max; the SM 6.6 two-arg form requires min <= max. Constant-fold the integer arguments and fire when the ordering is violated. Common authoring slip: a copy-paste of [WaveSize(64, 32)] from a wave64-then-wave32 RDNA snippet.

See the What it detects section of the rule page for the full pattern definition.

Why it matters

The full GPU-mechanism analysis lives in the Why it matters on a GPU section of the companion rule page.

Examples

The bad / good code snippets are kept canonical on the rule page; see wavesize-range-disordered.md -> Examples.

See also


This is a v1.0-ship stub. Full analysis pending; track issue link TBD.

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