[libclc] libclc: Update acosh (PR #188224)

Matt Arsenault via cfe-commits cfe-commits at lists.llvm.org
Tue Mar 24 04:22:29 PDT 2026


https://github.com/arsenm created https://github.com/llvm/llvm-project/pull/188224

libclc: Update acosh

This was originally ported from rocm device libs
in ca4d382e119e1389c83dbb07d9ca0085e88b2944. Merge in
more recent changes.

Remove unused ep_log

>From 217a3ef1c76d32892bce746895564995d1ae9674 Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault at amd.com>
Date: Sat, 21 Mar 2026 21:44:11 +0100
Subject: [PATCH 1/2] libclc: Update acosh

This was originally ported from rocm device libs
in ca4d382e119e1389c83dbb07d9ca0085e88b2944. Merge in
more recent changes.
---
 libclc/clc/lib/generic/math/clc_acosh.cl  |  15 +--
 libclc/clc/lib/generic/math/clc_acosh.inc | 114 +++++-----------------
 2 files changed, 29 insertions(+), 100 deletions(-)

diff --git a/libclc/clc/lib/generic/math/clc_acosh.cl b/libclc/clc/lib/generic/math/clc_acosh.cl
index cc73b76dd32f4..7eb505e4eca45 100644
--- a/libclc/clc/lib/generic/math/clc_acosh.cl
+++ b/libclc/clc/lib/generic/math/clc_acosh.cl
@@ -5,20 +5,13 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-
 #include "clc/clc_convert.h"
 #include "clc/float/definitions.h"
-#include "clc/internal/clc.h"
-#include "clc/math/clc_ep_log.h"
-#include "clc/math/clc_fabs.h"
-#include "clc/math/clc_fma.h"
-#include "clc/math/clc_log1p.h"
+#include "clc/math/clc_acosh.h"
+#include "clc/math/clc_ep.h"
+#include "clc/math/clc_log2_fast.h"
 #include "clc/math/clc_mad.h"
-#include "clc/math/clc_sqrt.h"
-#include "clc/math/math.h"
-#include "clc/relational/clc_isinf.h"
-#include "clc/relational/clc_isnan.h"
-#include "clc/relational/clc_select.h"
+#include "clc/math/clc_sqrt_fast.h"
 
 #define __CLC_BODY "clc_acosh.inc"
 #include "clc/math/gentype.inc"
diff --git a/libclc/clc/lib/generic/math/clc_acosh.inc b/libclc/clc/lib/generic/math/clc_acosh.inc
index 2f4a58742b8e3..02e623a650fc6 100644
--- a/libclc/clc/lib/generic/math/clc_acosh.inc
+++ b/libclc/clc/lib/generic/math/clc_acosh.inc
@@ -8,104 +8,40 @@
 
 #if __CLC_FPSIZE == 32
 
-_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_acosh(__CLC_GENTYPE x) {
-  __CLC_UINTN ux = __CLC_AS_UINTN(x);
-
-  // Arguments greater than 1/sqrt(epsilon) in magnitude are approximated by
-  // acosh(x) = ln(2) + ln(x)
-  // For 2.0 <= x <= 1/sqrt(epsilon) the approximation is:
-  //   acosh(x) = ln(x + sqrt(x * x - 1))
-  __CLC_INTN high = ux > 0x46000000U;
-  __CLC_INTN med = ux > 0x40000000U;
-
-  __CLC_GENTYPE w = x - 1.0f;
-  __CLC_GENTYPE s = w * w + 2.0f * w;
-  __CLC_GENTYPE t = x * x - 1.0f;
-  __CLC_GENTYPE r = __clc_sqrt(med ? t : s) + (med ? x : w);
-  __CLC_GENTYPE v = (high ? x : r) - (med ? 1.0f : 0.0f);
-  __CLC_GENTYPE z = __clc_log1p(v) + (high ? 0x1.62e430p-1f : 0.0f);
-
-  z = __clc_select(z, x, __clc_isnan(x) || __clc_isinf(x));
-  z = x < 1.0f ? __CLC_GENTYPE_NAN : z;
-
-  return z;
+_CLC_DEF _CLC_OVERLOAD _CLC_CONST __CLC_FLOATN __clc_acosh(__CLC_FLOATN x) {
+  __CLC_INTN b = x >= 0x1.0p+64f;
+  __CLC_FLOATN s = b ? 0x1.0p-64f : 1.0f;
+  __CLC_FLOATN sx = x * s;
+  __CLC_EP_PAIR a =
+      __clc_ep_add(sx, __clc_ep_sqrt(__clc_ep_sub(__clc_ep_sqr(sx), s * s)));
+  __CLC_FLOATN z = __clc_ep_ln_hi(a, b ? 64 : 0);
+
+  z = x == __CLC_GENTYPE_INF ? x : z;
+  return x < 1.0f ? FLT_NAN : z;
 }
 
 #elif __CLC_FPSIZE == 64
 
-_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_acosh(__CLC_GENTYPE x) {
-  // 1/sqrt(eps) = 9.49062656242515593767e+07
-  const __CLC_GENTYPE recrteps = 0x1.6a09e667f3bcdp+26;
-  // log2_lead and log2_tail sum to an extra-precise version of log(2)
-  const __CLC_GENTYPE log2_lead = 0x1.62e42ep-1;
-  const __CLC_GENTYPE log2_tail = 0x1.efa39ef35793cp-25;
-
-  // Handle x >= 128 here
-  __CLC_LONGN xlarge = x > recrteps;
-  __CLC_GENTYPE r = x + __clc_sqrt(__clc_fma(x, x, -1.0));
-  r = xlarge ? x : r;
-
-  __CLC_INTN xexp;
-  __CLC_GENTYPE r1, r2;
-  __clc_ep_log(r, &xexp, &r1, &r2);
-
-  __CLC_GENTYPE dxexp = __CLC_CONVERT_GENTYPE(
-      __CLC_CONVERT_LONGN(xexp) + (xlarge ? (__CLC_LONGN)1 : (__CLC_LONGN)0));
-  r1 = __clc_fma(dxexp, log2_lead, r1);
-  r2 = __clc_fma(dxexp, log2_tail, r2);
-
-  __CLC_GENTYPE ret1 = r1 + r2;
-
-  // Handle 1 < x < 128 here
-  // We compute the value
-  // t = x - 1.0 + sqrt(2.0*(x - 1.0) + (x - 1.0)*(x - 1.0))
-  // using simulated quad precision.
-  __CLC_GENTYPE t = x - 1.0;
-  __CLC_GENTYPE u1 = t * 2.0;
+_CLC_DEF _CLC_OVERLOAD _CLC_CONST __CLC_DOUBLEN __clc_acosh(__CLC_DOUBLEN x) {
+  __CLC_LONGN b = x >= 0x1.0p+512;
+  __CLC_DOUBLEN s = b ? 0x1.0p-512 : 1.0;
+  __CLC_DOUBLEN sx = x * s;
+  __CLC_EP_PAIR a =
+      __clc_ep_add(sx, __clc_ep_sqrt(__clc_ep_sub(__clc_ep_sqr(sx), s * s)));
+  __CLC_DOUBLEN z = __clc_ep_ln_hi(a, __CLC_CONVERT_INTN(b) ? 512 : 0);
 
-  // (t,0) * (t,0) -> (v1, v2)
-  __CLC_GENTYPE v1 = t * t;
-  __CLC_GENTYPE v2 = __clc_fma(t, t, -v1);
-
-  // (u1,0) + (v1,v2) -> (w1,w2)
-  r = u1 + v1;
-  __CLC_GENTYPE s = (((u1 - r) + v1) + v2);
-  __CLC_GENTYPE w1 = r + s;
-  __CLC_GENTYPE w2 = (r - w1) + s;
-
-  // sqrt(w1,w2) -> (u1,u2)
-  __CLC_GENTYPE p1 = __clc_sqrt(w1);
-  __CLC_GENTYPE a1 = p1 * p1;
-  __CLC_GENTYPE a2 = __clc_fma(p1, p1, -a1);
-  __CLC_GENTYPE temp = (((w1 - a1) - a2) + w2);
-  __CLC_GENTYPE p2 = MATH_DIVIDE(temp * 0.5, p1);
-  u1 = p1 + p2;
-  __CLC_GENTYPE u2 = (p1 - u1) + p2;
-
-  // (u1,u2) + (t,0) -> (r1,r2)
-  r = u1 + t;
-  s = ((u1 - r) + t) + u2;
-  // r1 = r + s;
-  // r2 = (r - r1) + s;
-  // t = r1 + r2;
-  t = r + s;
-
-  // For arguments 1.13 <= x <= 1.5 the log1p function is good enough
-  __CLC_GENTYPE ret2 = __clc_log1p(t);
-
-  __CLC_GENTYPE ret = x >= 128.0 ? ret1 : ret2;
-
-  ret = (__clc_isinf(x) || __clc_isnan(x)) ? x : ret;
-  ret = x == 1.0 ? 0.0 : ret;
-  ret = x < 1.0 ? __CLC_GENTYPE_NAN : ret;
-
-  return ret;
+  z = x == __CLC_GENTYPE_INF ? x : z;
+  return x < 1.0 ? DBL_NAN : z;
 }
 
 #elif __CLC_FPSIZE == 16
 
-_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_acosh(__CLC_GENTYPE x) {
-  return __CLC_CONVERT_GENTYPE(__clc_acosh(__CLC_CONVERT_FLOATN(x)));
+_CLC_DEF _CLC_OVERLOAD _CLC_CONST __CLC_HALFN __clc_acosh(__CLC_HALFN hx) {
+  __CLC_FLOATN x = __CLC_CONVERT_FLOATN(hx);
+  __CLC_FLOATN t = x + __clc_sqrt_fast(__clc_mad(x, x, -1.0f));
+  __CLC_HALFN ret = __CLC_CONVERT_HALFN(__clc_log2_fast(t) * 0x1.62e430p-1f);
+
+  return hx < 1.0h ? HALF_NAN : ret;
 }
 
 #endif

>From c7b8f25ea7c7f5a85ee64aca227aa490d77f4826 Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault at amd.com>
Date: Mon, 23 Mar 2026 19:25:01 +0100
Subject: [PATCH 2/2] Remove unused ep_log

---
 libclc/clc/include/clc/math/clc_ep_log.h      | 15 ----
 .../clc/include/clc/math/clc_ep_log_decl.inc  | 16 ----
 libclc/clc/lib/generic/CMakeLists.txt         |  1 -
 libclc/clc/lib/generic/math/clc_ep_log.cl     | 23 ------
 libclc/clc/lib/generic/math/clc_ep_log.inc    | 81 -------------------
 5 files changed, 136 deletions(-)
 delete mode 100644 libclc/clc/include/clc/math/clc_ep_log.h
 delete mode 100644 libclc/clc/include/clc/math/clc_ep_log_decl.inc
 delete mode 100644 libclc/clc/lib/generic/math/clc_ep_log.cl
 delete mode 100644 libclc/clc/lib/generic/math/clc_ep_log.inc

diff --git a/libclc/clc/include/clc/math/clc_ep_log.h b/libclc/clc/include/clc/math/clc_ep_log.h
deleted file mode 100644
index 8ac9546a844ed..0000000000000
--- a/libclc/clc/include/clc/math/clc_ep_log.h
+++ /dev/null
@@ -1,15 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef __CLC_MATH_CLC_EP_LOG_H__
-#define __CLC_MATH_CLC_EP_LOG_H__
-
-#define __CLC_BODY "clc/math/clc_ep_log_decl.inc"
-#include "clc/math/gentype.inc"
-
-#endif // __CLC_MATH_CLC_EP_LOG_H__
diff --git a/libclc/clc/include/clc/math/clc_ep_log_decl.inc b/libclc/clc/include/clc/math/clc_ep_log_decl.inc
deleted file mode 100644
index a255a6a453074..0000000000000
--- a/libclc/clc/include/clc/math/clc_ep_log_decl.inc
+++ /dev/null
@@ -1,16 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#if __CLC_FPSIZE == 64
-
-_CLC_DECL _CLC_OVERLOAD void __clc_ep_log(__CLC_GENTYPE x,
-                                          private __CLC_INTN *xexp,
-                                          private __CLC_GENTYPE *r1,
-                                          private __CLC_GENTYPE *r2);
-
-#endif
diff --git a/libclc/clc/lib/generic/CMakeLists.txt b/libclc/clc/lib/generic/CMakeLists.txt
index 8ad008a20bce3..03f4aa3e55a0a 100644
--- a/libclc/clc/lib/generic/CMakeLists.txt
+++ b/libclc/clc/lib/generic/CMakeLists.txt
@@ -77,7 +77,6 @@ libclc_configure_source_list(CLC_GENERIC_SOURCES
   math/clc_div_cr.cl
   math/clc_div_fast.cl
   math/clc_ep.cl
-  math/clc_ep_log.cl
   math/clc_erf.cl
   math/clc_erfc.cl
   math/clc_exp.cl
diff --git a/libclc/clc/lib/generic/math/clc_ep_log.cl b/libclc/clc/lib/generic/math/clc_ep_log.cl
deleted file mode 100644
index 2d228a0dbf193..0000000000000
--- a/libclc/clc/lib/generic/math/clc_ep_log.cl
+++ /dev/null
@@ -1,23 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifdef cl_khr_fp64
-
-#include "clc/clc_convert.h"
-#include "clc/internal/clc.h"
-#include "clc/math/clc_ep_log.h"
-#include "clc/math/clc_fma.h"
-#include "clc/math/math.h"
-#include "clc/math/tables.h"
-
-#pragma OPENCL EXTENSION cl_khr_fp64 : enable
-
-#define __CLC_BODY "clc_ep_log.inc"
-#include "clc/math/gentype.inc"
-
-#endif
diff --git a/libclc/clc/lib/generic/math/clc_ep_log.inc b/libclc/clc/lib/generic/math/clc_ep_log.inc
deleted file mode 100644
index d8cc886ffc745..0000000000000
--- a/libclc/clc/lib/generic/math/clc_ep_log.inc
+++ /dev/null
@@ -1,81 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-//
-// Computes natural log(x). Algorithm based on:
-// Ping-Tak Peter Tang
-// "Table-driven implementation of the logarithm function in IEEE floating-point
-// arithmetic"
-// ACM Transactions on Mathematical Software (TOMS) Volume 16, Issue 4 (December
-// 1990)
-//
-//===----------------------------------------------------------------------===//
-
-#if __CLC_FPSIZE == 64
-
-#define LN0 8.33333333333317923934e-02
-#define LN1 1.25000000037717509602e-02
-#define LN2 2.23213998791944806202e-03
-#define LN3 4.34887777707614552256e-04
-
-#define LF0 8.33333333333333593622e-02
-#define LF1 1.24999999978138668903e-02
-#define LF2 2.23219810758559851206e-03
-
-_CLC_DEF _CLC_OVERLOAD void __clc_ep_log(__CLC_GENTYPE x,
-                                         private __CLC_INTN *xexp,
-                                         private __CLC_GENTYPE *r1,
-                                         private __CLC_GENTYPE *r2) {
-  __CLC_LONGN near_one = x >= 0x1.e0faap-1 && x <= 0x1.1082cp+0;
-
-  __CLC_ULONGN ux = __CLC_AS_ULONGN(x);
-  __CLC_ULONGN uxs =
-      __CLC_AS_ULONGN(__CLC_AS_GENTYPE(0x03d0000000000000UL | ux) - 0x1.0p-962);
-  __CLC_LONGN c = ux < IMPBIT_DP64;
-  ux = c ? uxs : ux;
-  __CLC_INTN expadjust =
-      __CLC_CONVERT_INTN(c ? (__CLC_LONGN)60 : (__CLC_LONGN)0);
-
-  // Store the exponent of x in xexp and put f into the range [0.5,1)
-  __CLC_INTN xexp1 = __CLC_CONVERT_INTN((ux >> EXPSHIFTBITS_DP64) & 0x7ff) -
-                     EXPBIAS_DP64 - expadjust;
-  __CLC_GENTYPE f = __CLC_AS_GENTYPE(HALFEXPBITS_DP64 | (ux & MANTBITS_DP64));
-  *xexp = __CLC_CONVERT_INTN(near_one) ? 0 : xexp1;
-
-  __CLC_GENTYPE r = x - 1.0;
-  __CLC_GENTYPE u1 = MATH_DIVIDE(r, 2.0 + r);
-  __CLC_GENTYPE ru1 = -r * u1;
-  u1 = u1 + u1;
-
-  __CLC_INTN index = __CLC_CONVERT_INTN(ux >> 45);
-  index = ((0x80 | (index & 0x7e)) >> 1) + (index & 0x1);
-
-  __CLC_GENTYPE f1 = __CLC_CONVERT_GENTYPE(index) * 0x1.0p-7;
-  __CLC_GENTYPE f2 = f - f1;
-  __CLC_GENTYPE u2 = MATH_DIVIDE(f2, __clc_fma(0.5, f2, f1));
-
-  __CLC_GENTYPE z1 = __CLC_USE_TABLE(ln_tbl_lo, (index - 64));
-  __CLC_GENTYPE q = __CLC_USE_TABLE(ln_tbl_hi, (index - 64));
-
-  z1 = near_one ? r : z1;
-  q = near_one ? 0.0 : q;
-  __CLC_GENTYPE u = near_one ? u1 : u2;
-  __CLC_GENTYPE v = u * u;
-
-  __CLC_GENTYPE cc = near_one ? ru1 : u2;
-
-  __CLC_GENTYPE z21 =
-      __clc_fma(v, __clc_fma(v, __clc_fma(v, LN3, LN2), LN1), LN0);
-  __CLC_GENTYPE z22 = __clc_fma(v, __clc_fma(v, LF2, LF1), LF0);
-  __CLC_GENTYPE z2 = near_one ? z21 : z22;
-  z2 = __clc_fma(u * v, z2, cc) + q;
-
-  *r1 = z1;
-  *r2 = z2;
-}
-
-#endif



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