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-rw-r--r--libc/src/math/generic/atanhf16.cpp86
1 files changed, 2 insertions, 84 deletions
diff --git a/libc/src/math/generic/atanhf16.cpp b/libc/src/math/generic/atanhf16.cpp
index 57885ac..0539bac 100644
--- a/libc/src/math/generic/atanhf16.cpp
+++ b/libc/src/math/generic/atanhf16.cpp
@@ -7,92 +7,10 @@
//===----------------------------------------------------------------------===//
#include "src/math/atanhf16.h"
-#include "explogxf.h"
-#include "hdr/errno_macros.h"
-#include "hdr/fenv_macros.h"
-#include "src/__support/FPUtil/FEnvImpl.h"
-#include "src/__support/FPUtil/FPBits.h"
-#include "src/__support/FPUtil/PolyEval.h"
-#include "src/__support/FPUtil/cast.h"
-#include "src/__support/FPUtil/except_value_utils.h"
-#include "src/__support/FPUtil/multiply_add.h"
-#include "src/__support/common.h"
-#include "src/__support/macros/config.h"
-#include "src/__support/macros/optimization.h"
+#include "src/__support/math/atanhf16.h"
namespace LIBC_NAMESPACE_DECL {
-static constexpr size_t N_EXCEPTS = 1;
-static constexpr fputil::ExceptValues<float16, N_EXCEPTS> ATANHF16_EXCEPTS{{
- // (input, RZ output, RU offset, RD offset, RN offset)
- // x = 0x1.a5cp-4, atanhf16(x) = 0x1.a74p-4 (RZ)
- {0x2E97, 0x2E9D, 1, 0, 0},
-}};
-
-LLVM_LIBC_FUNCTION(float16, atanhf16, (float16 x)) {
- using FPBits = fputil::FPBits<float16>;
-
- FPBits xbits(x);
- Sign sign = xbits.sign();
- uint16_t x_abs = xbits.abs().uintval();
-
- // |x| >= 1
- if (LIBC_UNLIKELY(x_abs >= 0x3c00U)) {
- if (xbits.is_nan()) {
- if (xbits.is_signaling_nan()) {
- fputil::raise_except_if_required(FE_INVALID);
- return FPBits::quiet_nan().get_val();
- }
- return x;
- }
-
- // |x| == 1.0
- if (x_abs == 0x3c00U) {
- fputil::set_errno_if_required(ERANGE);
- fputil::raise_except_if_required(FE_DIVBYZERO);
- return FPBits::inf(sign).get_val();
- }
- // |x| > 1.0
- fputil::set_errno_if_required(EDOM);
- fputil::raise_except_if_required(FE_INVALID);
- return FPBits::quiet_nan().get_val();
- }
-
- if (auto r = ATANHF16_EXCEPTS.lookup(xbits.uintval());
- LIBC_UNLIKELY(r.has_value()))
- return r.value();
-
- // For |x| less than approximately 0.24
- if (LIBC_UNLIKELY(x_abs <= 0x33f3U)) {
- // atanh(+/-0) = +/-0
- if (LIBC_UNLIKELY(x_abs == 0U))
- return x;
- // The Taylor expansion of atanh(x) is:
- // atanh(x) = x + x^3/3 + x^5/5 + x^7/7 + x^9/9 + x^11/11
- // = x * [1 + x^2/3 + x^4/5 + x^6/7 + x^8/9 + x^10/11]
- // When |x| < 2^-5 (0x0800U), this can be approximated by:
- // atanh(x) ≈ x + (1/3)*x^3
- if (LIBC_UNLIKELY(x_abs < 0x0800U)) {
- float xf = x;
- return fputil::cast<float16>(xf + 0x1.555556p-2f * xf * xf * xf);
- }
-
- // For 2^-5 <= |x| <= 0x1.fccp-3 (~0.24):
- // Let t = x^2.
- // Define P(t) ≈ (1/3)*t + (1/5)*t^2 + (1/7)*t^3 + (1/9)*t^4 + (1/11)*t^5.
- // Coefficients (from Sollya, RN, hexadecimal):
- // 1/3 = 0x1.555556p-2, 1/5 = 0x1.99999ap-3, 1/7 = 0x1.24924ap-3,
- // 1/9 = 0x1.c71c72p-4, 1/11 = 0x1.745d18p-4
- // Thus, atanh(x) ≈ x * (1 + P(x^2)).
- float xf = x;
- float x2 = xf * xf;
- float pe = fputil::polyeval(x2, 0.0f, 0x1.555556p-2f, 0x1.99999ap-3f,
- 0x1.24924ap-3f, 0x1.c71c72p-4f, 0x1.745d18p-4f);
- return fputil::cast<float16>(fputil::multiply_add(xf, pe, xf));
- }
-
- float xf = x;
- return fputil::cast<float16>(0.5 * log_eval_f((xf + 1.0f) / (xf - 1.0f)));
-}
+LLVM_LIBC_FUNCTION(float16, atanhf16, (float16 x)) { return math::atanhf16(x); }
} // namespace LIBC_NAMESPACE_DECL