diff --git a/test/core/relaxed-simd/i16x8_relaxed_q15mulr_s.wast b/test/core/relaxed-simd/i16x8_relaxed_q15mulr_s.wast
index 265d9916..00f901cb 100644
--- a/test/core/relaxed-simd/i16x8_relaxed_q15mulr_s.wast
+++ b/test/core/relaxed-simd/i16x8_relaxed_q15mulr_s.wast
@@ -1,4 +1,6 @@
 ;; Tests for i16x8.relaxed_q15mulr_s.
+;; `either` comes from https://github.com/WebAssembly/threads.
+
 (module
     (func (export "i16x8.relaxed_q15mulr_s") (param v128 v128) (result v128) (i16x8.relaxed_q15mulr_s (local.get 0) (local.get 1)))
 
diff --git a/test/core/relaxed-simd/i32x4_relaxed_trunc.wast b/test/core/relaxed-simd/i32x4_relaxed_trunc.wast
index 889542c6..cca3ecb9 100644
--- a/test/core/relaxed-simd/i32x4_relaxed_trunc.wast
+++ b/test/core/relaxed-simd/i32x4_relaxed_trunc.wast
@@ -1,4 +1,5 @@
 ;; Tests for i32x4.relaxed_trunc_f32x4_s, i32x4.relaxed_trunc_f32x4_u, i32x4.relaxed_trunc_f64x2_s_zero, and i32x4.relaxed_trunc_f64x2_u_zero.
+;; `either` comes from https://github.com/WebAssembly/threads.
 
 (module
     (func (export "i32x4.relaxed_trunc_f32x4_s") (param v128) (result v128) (i32x4.relaxed_trunc_f32x4_s (local.get 0)))
diff --git a/test/core/relaxed-simd/i8x16_relaxed_swizzle.wast b/test/core/relaxed-simd/i8x16_relaxed_swizzle.wast
index 1b20668d..f1bcb455 100644
--- a/test/core/relaxed-simd/i8x16_relaxed_swizzle.wast
+++ b/test/core/relaxed-simd/i8x16_relaxed_swizzle.wast
@@ -1,4 +1,5 @@
 ;; Tests for relaxed i8x16 swizzle.
+;; `either` comes from https://github.com/WebAssembly/threads.
 
 (module
     (func (export "i8x16.relaxed_swizzle") (param v128 v128) (result v128) (i8x16.relaxed_swizzle (local.get 0) (local.get 1)))
diff --git a/test/core/relaxed-simd/relaxed_dot_product.wast b/test/core/relaxed-simd/relaxed_dot_product.wast
index 41dee0af..48714b87 100644
--- a/test/core/relaxed-simd/relaxed_dot_product.wast
+++ b/test/core/relaxed-simd/relaxed_dot_product.wast
@@ -1,4 +1,5 @@
 ;; Tests for relaxed dot products.
+;; `either` comes from https://github.com/WebAssembly/threads.
 
 (module
     (func (export "i16x8.relaxed_dot_i8x16_i7x16_s") (param v128 v128) (result v128) (i16x8.relaxed_dot_i8x16_i7x16_s (local.get 0) (local.get 1)))
diff --git a/test/core/relaxed-simd/relaxed_laneselect.wast b/test/core/relaxed-simd/relaxed_laneselect.wast
index 4ea6eb81..c43acb5e 100644
--- a/test/core/relaxed-simd/relaxed_laneselect.wast
+++ b/test/core/relaxed-simd/relaxed_laneselect.wast
@@ -1,4 +1,5 @@
 ;; Tests for i8x16.relaxed_laneselect, i16x8.relaxed_laneselect, i32x4.relaxed_laneselect, and i64x2.relaxed_laneselect.
+;; `either` comes from https://github.com/WebAssembly/threads.
 
 (module
     (func (export "i8x16.relaxed_laneselect") (param v128 v128 v128) (result v128) (i8x16.relaxed_laneselect (local.get 0) (local.get 1) (local.get 2)))
diff --git a/test/core/relaxed-simd/relaxed_madd_nmadd.wast b/test/core/relaxed-simd/relaxed_madd_nmadd.wast
index d3f76f81..40ce0ed3 100644
--- a/test/core/relaxed-simd/relaxed_madd_nmadd.wast
+++ b/test/core/relaxed-simd/relaxed_madd_nmadd.wast
@@ -1,4 +1,5 @@
 ;; Tests for f32x4.relaxed_madd, f32x4.relaxed_nmadd, f64x2.relaxed_madd, and f64x2.relaxed_nmadd.
+;; `either` comes from https://github.com/WebAssembly/threads.
 
 (module
     (func (export "f32x4.relaxed_madd") (param v128 v128 v128) (result v128) (f32x4.relaxed_madd (local.get 0) (local.get 1) (local.get 2)))
diff --git a/test/core/relaxed-simd/relaxed_min_max.wast b/test/core/relaxed-simd/relaxed_min_max.wast
index d8a04ba4..ac3ebb07 100644
--- a/test/core/relaxed-simd/relaxed_min_max.wast
+++ b/test/core/relaxed-simd/relaxed_min_max.wast
@@ -1,4 +1,5 @@
 ;; Tests for f32x4.min, f32x4.max, f64x2.min, and f64x2.max.
+;; `either` comes from https://github.com/WebAssembly/threads.
 
 (module
     (func (export "f32x4.relaxed_min") (param v128 v128) (result v128) (f32x4.relaxed_min (local.get 0) (local.get 1)))