1 files changed, 61 insertions, 0 deletions
diff --git a/math/aarch64/advsimd/log1p.c b/math/aarch64/advsimd/log1p.c
new file mode 100644
index 000000000000..42a0c5793920
--- /dev/null
+++ b/math/aarch64/advsimd/log1p.c
@@ -0,0 +1,61 @@
+/*
+ * Double-precision vector log(1+x) function.
+ *
+ * Copyright (c) 2022-2024, Arm Limited.
+ * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
+ */
+
+#include "v_math.h"
+#include "test_sig.h"
+#include "test_defs.h"
+
+#define WANT_V_LOG1P_K0_SHORTCUT 0
+#include "v_log1p_inline.h"
+
+const static struct data
+{
+  struct v_log1p_data d;
+  uint64x2_t inf, minus_one;
+} data = { .d = V_LOG1P_CONSTANTS_TABLE,
+	   .inf = V2 (0x7ff0000000000000),
+	   .minus_one = V2 (0xbff0000000000000) };
+
+#define BottomMask v_u64 (0xffffffff)
+
+static float64x2_t NOINLINE VPCS_ATTR
+special_case (float64x2_t x, uint64x2_t cmp, const struct data *d)
+{
+  /* Side-step special lanes so fenv exceptions are not triggered
+     inadvertently.  */
+  float64x2_t x_nospecial = v_zerofy_f64 (x, cmp);
+  return v_call_f64 (log1p, x, log1p_inline (x_nospecial, &d->d), cmp);
+}
+
+/* Vector log1p approximation using polynomial on reduced interval. Routine is
+   a modification of the algorithm used in scalar log1p, with no shortcut for
+   k=0 and no narrowing for f and k. Maximum observed error is 2.45 ULP:
+   _ZGVnN2v_log1p(0x1.658f7035c4014p+11) got 0x1.fd61d0727429dp+2
+					want 0x1.fd61d0727429fp+2 .  */
+VPCS_ATTR float64x2_t V_NAME_D1 (log1p) (float64x2_t x)
+{
+  const struct data *d = ptr_barrier (&data);
+  uint64x2_t ix = vreinterpretq_u64_f64 (x);
+  uint64x2_t ia = vreinterpretq_u64_f64 (vabsq_f64 (x));
+
+  uint64x2_t special_cases
+      = vorrq_u64 (vcgeq_u64 (ia, d->inf), vcgeq_u64 (ix, d->minus_one));
+
+  if (unlikely (v_any_u64 (special_cases)))
+    return special_case (x, special_cases, d);
+
+  return log1p_inline (x, &d->d);
+}
+
+TEST_SIG (V, D, 1, log1p, -0.9, 10.0)
+TEST_ULP (V_NAME_D1 (log1p), 1.95)
+TEST_DISABLE_FENV_IF_NOT (V_NAME_D1 (log1p), WANT_SIMD_EXCEPT)
+TEST_SYM_INTERVAL (V_NAME_D1 (log1p), 0.0, 0x1p-23, 50000)
+TEST_SYM_INTERVAL (V_NAME_D1 (log1p), 0x1p-23, 0.001, 50000)
+TEST_SYM_INTERVAL (V_NAME_D1 (log1p), 0.001, 1.0, 50000)
+TEST_INTERVAL (V_NAME_D1 (log1p), 1, inf, 40000)
+TEST_INTERVAL (V_NAME_D1 (log1p), -1.0, -inf, 500)