1 files changed, 87 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..752e2676e6
--- /dev/null
+++ b/dom/webgpu/tests/cts/checkout/src/webgpu/shader/execution/expression/call/builtin/step.spec.ts
@@ -0,0 +1,87 @@
+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 { TypeF32, TypeF16 } from '../../../../../util/conversion.js';
+import { FP } from '../../../../../util/floating_point.js';
+import { fullF32Range, fullF16Range } 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);
+
+// stepInterval's return value can't always be interpreted as a single acceptance
+// interval, valid result may be 0.0 or 1.0 or both of them, but will never be a
+// value in interval (0.0, 1.0).
+// See the comment block on stepInterval for more details
+const makeCase = (trait: 'f32' | 'f16', edge: number, x: number): Case => {
+  const FPTrait = FP[trait];
+  edge = FPTrait.quantize(edge);
+  x = FPTrait.quantize(x);
+  const expected = FPTrait.stepInterval(edge, x);
+
+  // [0, 0], [1, 1], or [-∞, +∞] cases
+  if (expected.isPoint() || !expected.isFinite()) {
+    return { input: [FPTrait.scalarBuilder(edge), FPTrait.scalarBuilder(x)], expected };
+  }
+
+  // [0, 1] case, valid result is either 0.0 or 1.0.
+  const zeroInterval = FPTrait.toInterval(0);
+  const oneInterval = FPTrait.toInterval(1);
+  return {
+    input: [FPTrait.scalarBuilder(edge), FPTrait.scalarBuilder(x)],
+    expected: anyOf(zeroInterval, oneInterval),
+  };
+};
+
+export const d = makeCaseCache('step', {
+  f32: () => {
+    return fullF32Range().flatMap(edge => fullF32Range().map(x => makeCase('f32', edge, x)));
+  },
+  f16: () => {
+    return fullF16Range().flatMap(edge => fullF16Range().map(x => makeCase('f16', edge, x)));
+  },
+});
+
+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)
+  )
+  .beforeAllSubcases(t => {
+    t.selectDeviceOrSkipTestCase('shader-f16');
+  })
+  .fn(async t => {
+    const cases = await d.get('f16');
+    await run(t, builtin('step'), [TypeF16, TypeF16], TypeF16, t.params, cases);
+  });