https://github.com/arsenm created https://github.com/llvm/llvm-project/pull/188225
None >From fcdd4d2694d90325ec8b63b7153e274a33d9d57f Mon Sep 17 00:00:00 2001 From: Matt Arsenault <[email protected]> Date: Sat, 21 Mar 2026 21:51:29 +0100 Subject: [PATCH] libclc: Update atanh --- libclc/clc/lib/generic/math/clc_atanh.cl | 11 ++- libclc/clc/lib/generic/math/clc_atanh.inc | 112 ++++++---------------- 2 files changed, 36 insertions(+), 87 deletions(-) diff --git a/libclc/clc/lib/generic/math/clc_atanh.cl b/libclc/clc/lib/generic/math/clc_atanh.cl index 456a3ac2624c3..312f1e3306b17 100644 --- a/libclc/clc/lib/generic/math/clc_atanh.cl +++ b/libclc/clc/lib/generic/math/clc_atanh.cl @@ -8,12 +8,13 @@ #include "clc/clc_convert.h" #include "clc/float/definitions.h" -#include "clc/internal/clc.h" +#include "clc/math/clc_atanh.h" +#include "clc/math/clc_copysign.h" +#include "clc/math/clc_ep.h" #include "clc/math/clc_fabs.h" -#include "clc/math/clc_fma.h" -#include "clc/math/clc_log1p.h" -#include "clc/math/clc_mad.h" -#include "clc/math/math.h" +#include "clc/math/clc_log2_fast.h" +#include "clc/math/clc_recip_fast.h" +#include "clc/relational/clc_isnan.h" #define __CLC_BODY "clc_atanh.inc" #include "clc/math/gentype.inc" diff --git a/libclc/clc/lib/generic/math/clc_atanh.inc b/libclc/clc/lib/generic/math/clc_atanh.inc index e76f340d8cd94..fc2c20a2bae07 100644 --- a/libclc/clc/lib/generic/math/clc_atanh.inc +++ b/libclc/clc/lib/generic/math/clc_atanh.inc @@ -8,98 +8,46 @@ #if __CLC_FPSIZE == 32 -_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_atanh(__CLC_GENTYPE x) { - __CLC_UINTN ux = __CLC_AS_UINTN(x); - __CLC_UINTN ax = ux & EXSIGNBIT_SP32; - __CLC_UINTN xs = ux ^ ax; - - // |x| > 1 or NaN - __CLC_GENTYPE z = __CLC_GENTYPE_NAN; - - // |x| == 1 - __CLC_GENTYPE t = __CLC_AS_GENTYPE(xs | PINFBITPATT_SP32); - z = ax == 0x3f800000U ? t : z; - - // 1/2 <= |x| < 1 - t = __CLC_AS_GENTYPE(ax); - t = MATH_DIVIDE(2.0f * t, 1.0f - t); - t = 0.5f * __clc_log1p(t); - t = __CLC_AS_GENTYPE(xs | __CLC_AS_UINTN(t)); - z = ax < 0x3f800000U ? t : z; - - // |x| < 1/2 - t = x * x; - __CLC_GENTYPE a = __clc_mad( - __clc_mad(0.92834212715e-2f, t, -0.28120347286e0f), t, 0.39453629046e0f); - __CLC_GENTYPE b = __clc_mad(__clc_mad(0.45281890445e0f, t, -0.15537744551e1f), - t, 0.11836088638e1f); - __CLC_GENTYPE p = MATH_DIVIDE(a, b); - t = __clc_mad(x * t, p, x); - z = ax < 0x3f000000 ? t : z; - - // |x| < 2^-13 - z = ax < 0x39000000U ? x : z; - - return z; +_CLC_DEF _CLC_OVERLOAD _CLC_CONST __CLC_FLOATN __clc_atanh(__CLC_FLOATN x) { + __CLC_FLOATN y = __clc_fabs(x); + __CLC_EP_PAIR a = + __clc_ep_fast_div(__clc_ep_fast_add(1.0f, y), __clc_ep_fast_sub(1.0f, y)); + __CLC_FLOATN z = 0.5f * __clc_ep_ln_hi(a, 0); + z = y < 0x1.0p-12f ? y : z; + + z = y > 1.0f ? FLT_NAN : z; + z = y == 1.0f ? __CLC_GENTYPE_INF : z; + return __clc_copysign(z, x); } #elif __CLC_FPSIZE == 64 -_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_atanh(__CLC_GENTYPE x) { - __CLC_GENTYPE absx = __clc_fabs(x); - - __CLC_GENTYPE ret = absx == 1.0 - ? __CLC_AS_GENTYPE((__CLC_ULONGN)PINFBITPATT_DP64) - : __CLC_GENTYPE_NAN; +_CLC_DEF _CLC_OVERLOAD _CLC_CONST __CLC_DOUBLEN __clc_atanh(__CLC_DOUBLEN x) { + __CLC_DOUBLEN y = __clc_fabs(x); + __CLC_EP_PAIR a = + __clc_ep_fast_div(__clc_ep_fast_add(1.0, y), __clc_ep_fast_sub(1.0, y)); + __CLC_DOUBLEN z = 0.5 * __clc_ep_ln_hi(a, 0); + z = y < 0x1.0p-27 ? y : z; - // |x| >= 0.5 - // Note that atanh(x) = 0.5 * ln((1+x)/(1-x)) - // For greater accuracy we use - // ln((1+x)/(1-x)) = ln(1 + 2x/(1-x)) = log1p(2x/(1-x)). - __CLC_GENTYPE r = 0.5 * __clc_log1p(2.0 * absx / (1.0 - absx)); - ret = absx < 1.0 ? r : ret; + z = y > 1.0 ? DBL_NAN : z; + z = y == 1.0 ? __CLC_GENTYPE_INF : z; - r = -ret; - ret = x < 0.0 ? r : ret; - - // Arguments up to 0.5 in magnitude are - // approximated by a [5,5] minimax polynomial - __CLC_GENTYPE t = x * x; - - __CLC_GENTYPE pn = __clc_fma( - t, - __clc_fma(t, - __clc_fma(t, - __clc_fma(t, - __clc_fma(t, -0.10468158892753136958e-3, - 0.28728638600548514553e-1), - -0.28180210961780814148e0), - 0.88468142536501647470e0), - -0.11028356797846341457e1), - 0.47482573589747356373e0); - - __CLC_GENTYPE pd = __clc_fma( - t, - __clc_fma(t, - __clc_fma(t, - __clc_fma(t, - __clc_fma(t, -0.35861554370169537512e-1, - 0.49561196555503101989e0), - -0.22608883748988489342e1), - 0.45414700626084508355e1), - -0.41631933639693546274e1), - 0.14244772076924206909e1); - - r = __clc_fma(x * t, pn / pd, x); - ret = absx < 0.5 ? r : ret; - - return ret; + return __clc_copysign(z, x); } #elif __CLC_FPSIZE == 16 -_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_atanh(__CLC_GENTYPE x) { - return __CLC_CONVERT_GENTYPE(__clc_atanh(__CLC_CONVERT_FLOATN(x))); +_CLC_DEF _CLC_OVERLOAD _CLC_CONST __CLC_HALFN __clc_atanh(__CLC_HALFN x) { + __CLC_HALFN absx = __clc_fabs(x); + __CLC_FLOATN absxf = __CLC_CONVERT_FLOATN(absx); + __CLC_FLOATN t = (1.0f + absxf) * __clc_recip_fast(1.0f - absxf); + __CLC_HALFN ret = __CLC_CONVERT_HALFN(__clc_log2_fast(t) * 0x1.62e430p-2f); + ret = absx < 0x1.0p-7h ? absx : ret; + + ret = absx == 1.0h ? __CLC_GENTYPE_INF : ret; + ret = (absx > 1.0h) || __clc_isnan(absx) ? HALF_NAN : ret; + + return __clc_copysign(ret, x); } #endif _______________________________________________ llvm-branch-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
