1 files changed, 85 insertions, 0 deletions
diff --git a/dom/webgpu/tests/cts/checkout/src/webgpu/shader/execution/expression/call/builtin/step.spec.ts b/dom/webgpu/tests/cts/checkout/src/webgpu/shader/execution/expression/call/builtin/step.spec.ts
new file mode 100644
index 0000000000..24226c9463
--- /dev/null
+++ b/dom/webgpu/tests/cts/checkout/src/webgpu/shader/execution/expression/call/builtin/step.spec.ts
@@ -0,0 +1,85 @@
+export const description = `
+Execution tests for the 'step' builtin function
+
+S is AbstractFloat, f32, f16
+T is S or vecN<S>
+@const fn step(edge: T ,x: T ) -> T
+Returns 1.0 if edge ≤ x, and 0.0 otherwise. Component-wise when T is a vector.
+`;
+
+import { makeTestGroup } from '../../../../../../common/framework/test_group.js';
+import { GPUTest } from '../../../../../gpu_test.js';
+import { anyOf } from '../../../../../util/compare.js';
+import { f32, TypeF32 } from '../../../../../util/conversion.js';
+import { stepInterval, toF32Interval } from '../../../../../util/f32_interval.js';
+import { fullF32Range, quantizeToF32 } from '../../../../../util/math.js';
+import { makeCaseCache } from '../../case_cache.js';
+import { allInputSources, Case, run } from '../../expression.js';
+
+import { builtin } from './builtin.js';
+
+export const g = makeTestGroup(GPUTest);
+
+export const d = makeCaseCache('step', {
+  f32: () => {
+    const zeroInterval = toF32Interval(0);
+    const oneInterval = toF32Interval(1);
+
+    // stepInterval's return value isn't always interpreted as an acceptance
+    // interval, so makeBinaryToF32IntervalCase cannot be used here.
+    // See the comment block on stepInterval for more details
+    const makeCase = (edge: number, x: number): Case => {
+      edge = quantizeToF32(edge);
+      x = quantizeToF32(x);
+      const expected = stepInterval(edge, x);
+
+      // [0, 0], [1, 1], or [-∞, +∞] cases
+      if (expected.isPoint() || !expected.isFinite()) {
+        return { input: [f32(edge), f32(x)], expected };
+      }
+
+      // [0, 1] case
+      return {
+        input: [f32(edge), f32(x)],
+        expected: anyOf(zeroInterval, oneInterval),
+      };
+    };
+
+    const range = fullF32Range();
+    const cases: Array<Case> = [];
+    range.forEach(edge => {
+      range.forEach(x => {
+        cases.push(makeCase(edge, x));
+      });
+    });
+
+    return cases;
+  },
+});
+
+g.test('abstract_float')
+  .specURL('https://www.w3.org/TR/WGSL/#float-builtin-functions')
+  .desc(`abstract float tests`)
+  .params(u =>
+    u.combine('inputSource', allInputSources).combine('vectorize', [undefined, 2, 3, 4] as const)
+  )
+  .unimplemented();
+
+g.test('f32')
+  .specURL('https://www.w3.org/TR/WGSL/#float-builtin-functions')
+  .desc(`f32 tests`)
+  .params(u =>
+    u.combine('inputSource', allInputSources).combine('vectorize', [undefined, 2, 3, 4] as const)
+  )
+  .fn(async t => {
+    const cases = await d.get('f32');
+    await run(t, builtin('step'), [TypeF32, TypeF32], TypeF32, t.params, cases);
+  });
+
+g.test('f16')
+  .specURL('https://www.w3.org/TR/WGSL/#float-builtin-functions')
+  .desc(`f16 tests`)
+  .params(u =>
+    u.combine('inputSource', allInputSources).combine('vectorize', [undefined, 2, 3, 4] as const)
+  )
+  .unimplemented();