TS8034

When it fires

workgroupBarrier() / storageBarrier() somewhere a barrier cannot stand (§25): in a vertex or fragment entry, which has no workgroup; or as a value, since a barrier is a statement (roadmap 0.2 item 5). A barrier or a workgroupUniformLoad under control flow the invocations do not share is UNIFORMITY (§54), not this.

Example

"use typeshade"

@fragment
export function main(@location(0) uv: vec2): vec4 {
  workgroupBarrier()
  return vec4(uv, 0., 1.)
}

Compiled at build time against the pinned compiler, this program gets:

How to fix it

The same program, corrected. It compiles with no diagnostic.

"use typeshade"

@fragment
export function main(@location(0) uv: vec2): vec4 {
  return vec4(uv, 0., 1.)
}

The rule this enforces

Rule 8.3 Test

A builtin WGSL confines by stage may be used in an entry of a permitted stage, and in a helper that no entry of an excluded stage can reach.

See also

TS8052 UNIFORMITY

A call that needs uniform control flow — textureSample and the other implicit-LOD forms, the derivatives, a barrier, or workgroupUniformLoad — reached under a condition that is not uniform across the invocations that run together (an if, a switch, a loop's condition, the left side of && or ||, the condition of a ?: WGSL writes as an if), or after a return, break or continue taken under one (§54).

• Control flow
• workgroupBarrier
• storageBarrier
• workgroupUniformLoad
• Error codes

Source

Where the compiler raises this code at commit 26de7be8, one line per file:

• src/compiler/ts/lower/barriers.ts:73
• src/compiler/ts/lower/expression-call.ts:431