[libc][math] Refactor coshf implementation to header-only in src/__support/math folder.

libc/shared/math.h

@@ -35,6 +35,7 @@
 #include "math/cos.h"
 #include "math/cosf.h"
 #include "math/cosf16.h"
+#include "math/coshf.h"
 #include "math/erff.h"
 #include "math/exp.h"
 #include "math/exp10.h"

libc/shared/math/coshf.h

@@ -0,0 +1,23 @@
+//===-- Shared coshf function -----------------------------------*- C++ -*-===//
+//
+// 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 LLVM_LIBC_SHARED_MATH_COSHF_H
+#define LLVM_LIBC_SHARED_MATH_COSHF_H
+
+#include "shared/libc_common.h"
+#include "src/__support/math/coshf.h"
+
+namespace LIBC_NAMESPACE_DECL {
+namespace shared {
+
+using math::coshf;
+
+} // namespace shared
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SHARED_MATH_COSHF_H

libc/src/__support/math/CMakeLists.txt

@@ -407,6 +407,18 @@ add_header_library(
     libc.src.__support.macros.properties.types
 )
 
+add_header_library(
+  coshf
+  HDRS
+    coshf.h
+  DEPENDS
+    .sinhfcoshf_utils
+    libc.src.__support.FPUtil.fp_bits
+    libc.src.__support.FPUtil.multiply_add
+    libc.src.__support.FPUtil.rounding_mode
+    libc.src.__support.macros.optimization
+)
+
 add_header_library(
   erff
   HDRS
@@ -726,3 +738,12 @@ add_header_library(
     libc.src.__support.FPUtil.nearest_integer
     libc.src.__support.common
 )
+
+add_header_library(
+  sinhfcoshf_utils
+  HDRS
+    sinhfcoshf_utils.h
+  DEPENDS
+    .exp10f_utils
+    libc.src.__support.FPUtil.multiply_add
+)

libc/src/__support/math/coshf.h

@@ -0,0 +1,65 @@
+//===-- Implementation header for coshf -------------------------*- C++ -*-===//
+//
+// 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 LLVM_LIBC_SRC___SUPPORT_MATH_COSHF_H
+#define LLVM_LIBC_SRC___SUPPORT_MATH_COSHF_H
+
+#include "sinhfcoshf_utils.h"
+#include "src/__support/FPUtil/FEnvImpl.h"
+#include "src/__support/FPUtil/FPBits.h"
+#include "src/__support/FPUtil/rounding_mode.h"
+#include "src/__support/macros/config.h"
+#include "src/__support/macros/optimization.h" // LIBC_UNLIKELY
+
+namespace LIBC_NAMESPACE_DECL {
+
+namespace math {
+
+LIBC_INLINE static constexpr float coshf(float x) {
+  using namespace sinhfcoshf_internal;
+  using FPBits = typename fputil::FPBits<float>;
+
+  FPBits xbits(x);
+  xbits.set_sign(Sign::POS);
+  x = xbits.get_val();
+
+  uint32_t x_u = xbits.uintval();
+
+  // When |x| >= 90, or x is inf or nan
+  if (LIBC_UNLIKELY(x_u >= 0x42b4'0000U || x_u <= 0x3280'0000U)) {
+    // |x| <= 2^-26
+    if (x_u <= 0x3280'0000U) {
+      return 1.0f + x;
+    }
+
+    if (xbits.is_inf_or_nan())
+      return x + FPBits::inf().get_val();
+
+    int rounding = fputil::quick_get_round();
+    if (LIBC_UNLIKELY(rounding == FE_DOWNWARD || rounding == FE_TOWARDZERO))
+      return FPBits::max_normal().get_val();
+
+    fputil::set_errno_if_required(ERANGE);
+    fputil::raise_except_if_required(FE_OVERFLOW);
+
+    return x + FPBits::inf().get_val();
+  }
+
+  // TODO: We should be able to reduce the latency and reciprocal throughput
+  // further by using a low degree (maybe 3-7 ?) minimax polynomial for small
+  // but not too small inputs, such as |x| < 2^-2, or |x| < 2^-3.
+
+  // cosh(x) = (e^x + e^(-x)) / 2.
+  return static_cast<float>(exp_pm_eval</*is_sinh*/ false>(x));
+}
+
+} // namespace math
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_MATH_COSHF_H

libc/src/math/generic/explogxf.h → libc/src/__support/math/sinhfcoshf_utils.h

@@ -1,26 +1,22 @@
-//===-- Single-precision general exp/log functions ------------------------===//
+//===-- Single-precision general sinhf/coshf functions --------------------===//
 //
 // 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 LLVM_LIBC_SRC_MATH_GENERIC_EXPLOGXF_H
-#define LLVM_LIBC_SRC_MATH_GENERIC_EXPLOGXF_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_MATH_SINHFCOSHF_UTILS_H
+#define LLVM_LIBC_SRC___SUPPORT_MATH_SINHFCOSHF_UTILS_H
 
-#include "common_constants.h"
-
-#include "src/__support/common.h"
-#include "src/__support/macros/properties/cpu_features.h"
-#include "src/__support/math/acoshf_utils.h"
-#include "src/__support/math/exp10f_utils.h"
-#include "src/__support/math/exp_utils.h"
+#include "exp10f_utils.h"
+#include "src/__support/FPUtil/multiply_add.h"
 
 namespace LIBC_NAMESPACE_DECL {
 
-constexpr int LOG_P1_BITS = 6;
-constexpr int LOG_P1_SIZE = 1 << LOG_P1_BITS;
+namespace math {
+
+namespace sinhfcoshf_internal {
 
 // The function correctly calculates sinh(x) and cosh(x) by calculating exp(x)
 // and exp(-x) simultaneously.
@@ -121,6 +117,10 @@ template <bool is_sinh> LIBC_INLINE double exp_pm_eval(float x) {
   return r;
 }
 
+} // namespace sinhfcoshf_internal
+
+} // namespace math
+
 } // namespace LIBC_NAMESPACE_DECL
 
-#endif // LLVM_LIBC_SRC_MATH_GENERIC_EXPLOGXF_H
+#endif // LLVM_LIBC_SRC___SUPPORT_MATH_SINHFCOSHF_UTILS_H

libc/src/math/generic/CMakeLists.txt

@@ -1344,7 +1344,6 @@ add_entrypoint_object(
     ../exp2.h
   DEPENDS
     .common_constants
-    .explogxf
     libc.src.__support.CPP.bit
     libc.src.__support.CPP.optional
     libc.src.__support.FPUtil.dyadic_float
@@ -1357,6 +1356,7 @@ add_entrypoint_object(
     libc.src.__support.FPUtil.triple_double
     libc.src.__support.integer_literals
     libc.src.__support.macros.optimization
+    libc.src.__support.math.exp_utils
     libc.src.errno.errno
 )
 
@@ -1365,7 +1365,6 @@ add_header_library(
   HDRS
     exp2f_impl.h
   DEPENDS
-    .explogxf
     libc.src.__support.FPUtil.except_value_utils
     libc.src.__support.FPUtil.fenv_impl
     libc.src.__support.FPUtil.fp_bits
@@ -1374,6 +1373,7 @@ add_header_library(
     libc.src.__support.FPUtil.polyeval
     libc.src.__support.FPUtil.rounding_mode
     libc.src.__support.macros.optimization
+    libc.src.__support.math.exp10f_utils
     libc.src.__support.common
     libc.src.errno.errno
 )
@@ -1413,7 +1413,6 @@ add_entrypoint_object(
   HDRS
     ../exp2m1f.h
   DEPENDS
-    .explogxf
     libc.src.errno.errno
     libc.src.__support.common
     libc.src.__support.FPUtil.except_value_utils
@@ -1424,6 +1423,7 @@ add_entrypoint_object(
     libc.src.__support.FPUtil.rounding_mode
     libc.src.__support.macros.optimization
     libc.src.__support.macros.properties.cpu_features
+    libc.src.__support.math.exp10f_utils
 )
 
 add_entrypoint_object(
@@ -1488,7 +1488,6 @@ add_entrypoint_object(
   HDRS
     ../exp10m1f.h
   DEPENDS
-    .explogxf
     libc.src.errno.errno
     libc.src.__support.common
     libc.src.__support.FPUtil.except_value_utils
@@ -1498,6 +1497,7 @@ add_entrypoint_object(
     libc.src.__support.FPUtil.polyeval
     libc.src.__support.FPUtil.rounding_mode
     libc.src.__support.macros.optimization
+    libc.src.__support.math.exp10f_utils
 )
 
 add_entrypoint_object(
@@ -1529,14 +1529,11 @@ add_entrypoint_object(
     ../expm1.h
   DEPENDS
     .common_constants
-    .explogxf
     libc.src.__support.CPP.bit
-    libc.src.__support.CPP.optional
     libc.src.__support.FPUtil.dyadic_float
     libc.src.__support.FPUtil.fenv_impl
     libc.src.__support.FPUtil.fp_bits
     libc.src.__support.FPUtil.multiply_add
-    libc.src.__support.FPUtil.nearest_integer
     libc.src.__support.FPUtil.polyeval
     libc.src.__support.FPUtil.rounding_mode
     libc.src.__support.FPUtil.triple_double
@@ -1593,7 +1590,6 @@ add_entrypoint_object(
   DEPENDS
     .common_constants
     .exp2f_impl
-    .explogxf
     libc.src.__support.math.exp10f
     libc.src.__support.CPP.bit
     libc.src.__support.FPUtil.fenv_impl
@@ -3905,31 +3901,14 @@ add_entrypoint_object(
     libc.src.__support.FPUtil.nearest_integer_operations
 )
 
-#TODO: Add errno include to the hyperbolic functions.
-add_header_library(
-  explogxf
-  HDRS
-    explogxf.h
-  DEPENDS
-    .common_constants
-    libc.src.__support.math.exp_utils
-    libc.src.__support.math.acoshf_utils
-    libc.src.__support.macros.properties.cpu_features
-    libc.src.errno.errno
-)
-
 add_entrypoint_object(
   coshf
   SRCS
     coshf.cpp
   HDRS
     ../coshf.h
   DEPENDS
-    .explogxf
-    libc.src.__support.FPUtil.fp_bits
-    libc.src.__support.FPUtil.multiply_add
-    libc.src.__support.FPUtil.rounding_mode
-    libc.src.__support.macros.optimization
+    libc.src.__support.math.coshf
 )
 
 add_entrypoint_object(
@@ -3956,10 +3935,10 @@ add_entrypoint_object(
   HDRS
     ../sinhf.h
   DEPENDS
-    .explogxf
     libc.src.__support.FPUtil.fp_bits
     libc.src.__support.FPUtil.rounding_mode
     libc.src.__support.macros.optimization
+    libc.src.__support.math.sinhfcoshf_utils
 )
 
 add_entrypoint_object(
@@ -3973,7 +3952,7 @@ add_entrypoint_object(
     libc.hdr.errno_macros
     libc.hdr.fenv_macros
     libc.src.__support.FPUtil.except_value_utils
-    libc.src.__support.FPUtil.fenv_impl
+    libc.src.__support.FPUtil.fenv_impl 
     libc.src.__support.FPUtil.fp_bits
     libc.src.__support.FPUtil.rounding_mode
     libc.src.__support.macros.optimization
@@ -3986,12 +3965,12 @@ add_entrypoint_object(
   HDRS
     ../tanhf.h
   DEPENDS
-    .explogxf
     libc.src.__support.FPUtil.fp_bits
     libc.src.__support.FPUtil.rounding_mode
     libc.src.__support.FPUtil.multiply_add
     libc.src.__support.FPUtil.polyeval
     libc.src.__support.macros.optimization
+    libc.src.__support.math.exp10f_utils
 )
 
 add_entrypoint_object(
@@ -4022,7 +4001,6 @@ add_entrypoint_object(
   HDRS
     ../acoshf.h
   DEPENDS
-    .explogxf
     libc.src.__support.math.acoshf
 )
 

libc/src/math/generic/acoshf.cpp

@@ -7,7 +7,6 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/math/acoshf.h"
-
 #include "src/__support/math/acoshf.h"
 
 namespace LIBC_NAMESPACE_DECL {