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Improve SIMD test diversity

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
45/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
wasm
Domain
testing-qa

Research direction

Start by locating the existing SIMD test files and reviewing their current assertions. Add representative lane-distinguishing cases like the narrow and truncation examples in the issue, along with other under-tested SIMD operations. Done means the suite covers lane ordering and produces distinct expected vectors for these operations.

Written by the indexing model from the issue text.

Description

SIMD tests do not have enough diversity to catch e.g. swapped lanes. It would be useful to have tests like:

(assert_return (invoke "i8x16.narrow_i16x8_s" (v128.const i16x8 0 1 2 3 4 5 6 7)
                                              (v128.const i16x8 8 9 10 11 12 13 14 15))
                                              (v128.const i8x16 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15))
(assert_return (invoke "i8x16.narrow_i16x8_u" (v128.const i16x8 0 1 2 3 4 5 6 7)
                                              (v128.const i16x8 8 9 10 11 12 13 14 15))
                                              (v128.const i8x16 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15))
(assert_return (invoke "i16x8.narrow_i32x4_s" (v128.const i32x4 1 2 3 4)
                                              (v128.const i32x4 5 6 7 8))
                                              (v128.const i16x8 1 2 3 4 5 6 7 8))
(assert_return (invoke "i16x8.narrow_i32x4_u" (v128.const i32x4 1 2 3 4)
                                              (v128.const i32x4 5 6 7 8))
                                              (v128.const i16x8 1 2 3 4 5 6 7 8))
(assert_return (invoke "i32x4.trunc_sat_f64x2_s_zero" (v128.const f64x2 1.0 2.0))
                                                      (v128.const i32x4 1 2 0 0))
(assert_return (invoke "i32x4.trunc_sat_f64x2_u_zero" (v128.const f64x2 1.0 2.0))
                                                      (v128.const i32x4 1 2 0 0))

among others.

Dominant language
WebAssembly
Stars
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Forks
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Avg merge
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Merged PRs (30d)
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Getting set up

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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