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diff --git a/math/aarch64/experimental/asinf_2u5.c b/math/aarch64/experimental/asinf_2u5.c
new file mode 100644
index 000000000000..1136da01550e
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+++ b/math/aarch64/experimental/asinf_2u5.c
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+/*
+ * Single-precision asin(x) function.
+ *
+ * Copyright (c) 2023-2024, Arm Limited.
+ * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
+ */
+
+#include "poly_scalar_f32.h"
+#include "math_config.h"
+#include "test_sig.h"
+#include "test_defs.h"
+
+#define AbsMask 0x7fffffff
+#define Half 0x3f000000
+#define One 0x3f800000
+#define PiOver2f 0x1.921fb6p+0f
+#define Small 0x39800000 /* 2^-12.  */
+#define Small12 0x398
+#define QNaN 0x7fc
+
+/* Fast implementation of single-precision asin(x) based on polynomial
+   approximation.
+
+   For x < Small, approximate asin(x) by x. Small = 2^-12 for correct rounding.
+
+   For x in [Small, 0.5], use order 4 polynomial P such that the final
+   approximation is an odd polynomial: asin(x) ~ x + x^3 P(x^2).
+
+   The largest observed error in this region is 0.83 ulps,
+     asinf(0x1.ea00f4p-2) got 0x1.fef15ep-2 want 0x1.fef15cp-2.
+
+   No cheap approximation can be obtained near x = 1, since the function is not
+   continuously differentiable on 1.
+
+   For x in [0.5, 1.0], we use a method based on a trigonometric identity
+
+     asin(x) = pi/2 - acos(x)
+
+   and a generalized power series expansion of acos(y) near y=1, that reads as
+
+     acos(y)/sqrt(2y) ~ 1 + 1/12 * y + 3/160 * y^2 + ... (1)
+
+   The Taylor series of asin(z) near z = 0, reads as
+
+     asin(z) ~ z + z^3 P(z^2) = z + z^3 * (1/6 + 3/40 z^2 + ...).
+
+   Therefore, (1) can be written in terms of P(y/2) or even asin(y/2)
+
+     acos(y) ~ sqrt(2y) (1 + y/2 * P(y/2)) = 2 * sqrt(y/2) (1 + y/2 * P(y/2)
+
+   Hence, if we write z = (1-x)/2, z is near 0 when x approaches 1 and
+
+     asin(x) ~ pi/2 - acos(x) ~ pi/2 - 2 * sqrt(z) (1 + z * P(z)).
+
+   The largest observed error in this region is 2.41 ulps,
+     asinf(0x1.00203ep-1) got 0x1.0c3a64p-1 want 0x1.0c3a6p-1.  */
+float
+asinf (float x)
+{
+  uint32_t ix = asuint (x);
+  uint32_t ia = ix & AbsMask;
+  uint32_t ia12 = ia >> 20;
+  float ax = asfloat (ia);
+  uint32_t sign = ix & ~AbsMask;
+
+  /* Special values and invalid range.  */
+  if (unlikely (ia12 == QNaN))
+    return x;
+  if (ia > One)
+    return __math_invalidf (x);
+  if (ia12 < Small12)
+    return x;
+
+  /* Evaluate polynomial Q(x) = y + y * z * P(z) with
+     z2 = x ^ 2         and z = |x|     , if |x| < 0.5
+     z2 = (1 - |x|) / 2 and z = sqrt(z2), if |x| >= 0.5.  */
+  float z2 = ax < 0.5 ? x * x : fmaf (-0.5f, ax, 0.5f);
+  float z = ax < 0.5 ? ax : sqrtf (z2);
+
+  /* Use a single polynomial approximation P for both intervals.  */
+  float p = horner_4_f32 (z2, __asinf_poly);
+  /* Finalize polynomial: z + z * z2 * P(z2).  */
+  p = fmaf (z * z2, p, z);
+
+  /* asin(|x|) = Q(|x|)         , for |x| < 0.5
+	       = pi/2 - 2 Q(|x|), for |x| >= 0.5.  */
+  float y = ax < 0.5 ? p : fmaf (-2.0f, p, PiOver2f);
+
+  /* Copy sign.  */
+  return asfloat (asuint (y) | sign);
+}
+
+TEST_SIG (S, F, 1, asin, -1.0, 1.0)
+TEST_ULP (asinf, 1.91)
+TEST_INTERVAL (asinf, 0, Small, 5000)
+TEST_INTERVAL (asinf, Small, 0.5, 50000)
+TEST_INTERVAL (asinf, 0.5, 1.0, 50000)
+TEST_INTERVAL (asinf, 1.0, 0x1p11, 50000)
+TEST_INTERVAL (asinf, 0x1p11, inf, 20000)
+TEST_INTERVAL (asinf, -0, -inf, 20000)