1 files changed, 83 insertions, 0 deletions
diff --git a/dom/webgpu/tests/cts/checkout/src/webgpu/api/validation/render_pipeline/multisample_state.spec.ts b/dom/webgpu/tests/cts/checkout/src/webgpu/api/validation/render_pipeline/multisample_state.spec.ts
new file mode 100644
index 0000000000..053b00e6a3
--- /dev/null
+++ b/dom/webgpu/tests/cts/checkout/src/webgpu/api/validation/render_pipeline/multisample_state.spec.ts
@@ -0,0 +1,83 @@
+export const description = `
+This test dedicatedly tests validation of GPUMultisampleState of createRenderPipeline.
+`;
+
+import { makeTestGroup } from '../../../../common/framework/test_group.js';
+import { kDefaultFragmentShaderCode } from '../../../util/shader.js';
+
+import { CreateRenderPipelineValidationTest } from './common.js';
+
+export const g = makeTestGroup(CreateRenderPipelineValidationTest);
+
+g.test('count')
+  .desc(`If multisample.count must either be 1 or 4.`)
+  .params(u =>
+    u
+      .combine('isAsync', [false, true])
+      .beginSubcases()
+      .combine('count', [0, 1, 2, 3, 4, 8, 16, 1024])
+  )
+  .fn(async t => {
+    const { isAsync, count } = t.params;
+
+    const descriptor = t.getDescriptor({ multisample: { count, alphaToCoverageEnabled: false } });
+
+    const _success = count === 1 || count === 4;
+    t.doCreateRenderPipelineTest(isAsync, _success, descriptor);
+  });
+
+g.test('alpha_to_coverage,count')
+  .desc(
+    `If multisample.alphaToCoverageEnabled is true, multisample.count must be greater than 1, e.g. it can only be 4.`
+  )
+  .params(u =>
+    u
+      .combine('isAsync', [false, true])
+      .combine('alphaToCoverageEnabled', [false, true])
+      .beginSubcases()
+      .combine('count', [1, 4])
+  )
+  .fn(async t => {
+    const { isAsync, alphaToCoverageEnabled, count } = t.params;
+
+    const descriptor = t.getDescriptor({ multisample: { count, alphaToCoverageEnabled } });
+
+    const _success = alphaToCoverageEnabled ? count === 4 : count === 1 || count === 4;
+    t.doCreateRenderPipelineTest(isAsync, _success, descriptor);
+  });
+
+g.test('alpha_to_coverage,sample_mask')
+  .desc(
+    `If sample_mask builtin is a pipeline output of fragment, multisample.alphaToCoverageEnabled should be false.`
+  )
+  .params(u =>
+    u
+      .combine('isAsync', [false, true])
+      .combine('alphaToCoverageEnabled', [false, true])
+      .beginSubcases()
+      .combine('hasSampleMaskOutput', [false, true])
+  )
+  .fn(async t => {
+    const { isAsync, alphaToCoverageEnabled, hasSampleMaskOutput } = t.params;
+
+    const descriptor = t.getDescriptor({
+      multisample: { alphaToCoverageEnabled, count: 4 },
+      fragmentShaderCode: hasSampleMaskOutput
+        ? `
+      struct Output {
+        @builtin(sample_mask) mask_out: u32,
+        @location(0) color : vec4<f32>,
+      }
+      @fragment fn main() -> Output {
+        var o: Output;
+        // We need to make sure this sample_mask isn't optimized out even its value equals "no op".
+        o.mask_out = 0xFFFFFFFFu;
+        o.color = vec4<f32>(1.0, 1.0, 1.0, 1.0);
+        return o;
+      }`
+        : kDefaultFragmentShaderCode,
+    });
+
+    const _success = !hasSampleMaskOutput || !alphaToCoverageEnabled;
+    t.doCreateRenderPipelineTest(isAsync, _success, descriptor);
+  });