[lib][NFC] Split the floating point util functions into multiple files.

The grouping now reflects the grouping on cppreference.com.

5 files changed, 278 insertions, 217 deletions

diff --git a/libc/utils/FPUtil/BasicOperations.h b/libc/utils/FPUtil/BasicOperations.h
new file mode 100644
index 0000000..d5c7004
--- /dev/null
+++ b/libc/utils/FPUtil/BasicOperations.h
@@ -0,0 +1,21 @@
+//===-- Basic operations on floating point numbers --------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "FloatOperations.h"
+
+namespace __llvm_libc {
+namespace fputil {
+
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline T abs(T x) {
+  return valueFromBits(absBits(x));
+}
+
+} // namespace fputil
+} // namespace __llvm_libc
diff --git a/libc/utils/FPUtil/ClassificationFunctions.h b/libc/utils/FPUtil/ClassificationFunctions.h
new file mode 100644
index 0000000..a80e349
--- /dev/null
+++ b/libc/utils/FPUtil/ClassificationFunctions.h
@@ -0,0 +1,90 @@
+//===-- Floating point classification functions -----------------*- 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_UTILS_FPUTIL_CLASSIFICATION_FUNCTIONS_H
+#define LLVM_LIBC_UTILS_FPUTIL_CLASSIFICATION_FUNCTIONS_H
+
+#include "BitPatterns.h"
+#include "FloatOperations.h"
+#include "FloatProperties.h"
+
+#include "utils/CPP/TypeTraits.h"
+
+namespace __llvm_libc {
+namespace fputil {
+
+template <typename BitsType> static inline bool bitsAreInf(BitsType bits) {
+  using FPType = typename FloatType<BitsType>::Type;
+  return ((bits & BitPatterns<FPType>::inf) == BitPatterns<FPType>::inf) &&
+         ((bits & FloatProperties<FPType>::mantissaMask) == 0);
+}
+
+// Return true if x is infinity (positive or negative.)
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline bool isInf(T x) {
+  return bitsAreInf(valueAsBits(x));
+}
+
+template <typename BitsType> static inline bool bitsAreNaN(BitsType bits) {
+  using FPType = typename FloatType<BitsType>::Type;
+  return ((bits & BitPatterns<FPType>::inf) == BitPatterns<FPType>::inf) &&
+         ((bits & FloatProperties<FPType>::mantissaMask) != 0);
+}
+
+// Return true if x is a NAN (quiet or signalling.)
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline bool isNaN(T x) {
+  return bitsAreNaN(valueAsBits(x));
+}
+
+template <typename BitsType> static inline bool bitsAreInfOrNaN(BitsType bits) {
+  using FPType = typename FloatType<BitsType>::Type;
+  return (bits & BitPatterns<FPType>::inf) == BitPatterns<FPType>::inf;
+}
+
+template <typename BitsType> static inline bool bitsAreZero(BitsType bits) {
+  using FPType = typename FloatType<BitsType>::Type;
+  return (bits == BitPatterns<FPType>::zero) ||
+         (bits == BitPatterns<FPType>::negZero);
+}
+
+// Return true if x is any kind of NaN or infinity.
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline bool isInfOrNaN(T x) {
+  return bitsAreInfOrNaN(valueAsBits(x));
+}
+
+// Return true if x is a quiet NAN.
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline bool isQuietNaN(T x) {
+  using Properties = FloatProperties<T>;
+  using BitsType = typename FloatProperties<T>::BitsType;
+  BitsType bits = valueAsBits(x);
+  return ((bits & BitPatterns<T>::inf) == BitPatterns<T>::inf) &&
+         ((bits & Properties::quietNaNMask) != 0);
+}
+
+// Return true if x is a quiet NAN with sign bit set.
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline bool isNegativeQuietNaN(T x) {
+  using Properties = FloatProperties<T>;
+  using BitsType = typename FloatProperties<T>::BitsType;
+  BitsType bits = valueAsBits(x);
+  return ((bits & BitPatterns<T>::negInf) == BitPatterns<T>::negInf) &&
+         ((bits & Properties::quietNaNMask) != 0);
+}
+
+} // namespace fputil
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_UTILS_FPUTIL_CLASSIFICATION_FUNCTIONS_H
diff --git a/libc/utils/FPUtil/FloatOperations.h b/libc/utils/FPUtil/FloatOperations.h
index b599aad..0739548f 100644
--- a/libc/utils/FPUtil/FloatOperations.h
+++ b/libc/utils/FPUtil/FloatOperations.h
@@ -57,222 +57,6 @@ static inline int getExponent(T x) {
   return getExponentFromBits(valueAsBits(x));
 }
 
-template <typename BitsType> static inline bool bitsAreInf(BitsType bits) {
-  using FPType = typename FloatType<BitsType>::Type;
-  return ((bits & BitPatterns<FPType>::inf) == BitPatterns<FPType>::inf) &&
-         ((bits & FloatProperties<FPType>::mantissaMask) == 0);
-}
-
-// Return true if x is infinity (positive or negative.)
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline bool isInf(T x) {
-  return bitsAreInf(valueAsBits(x));
-}
-
-template <typename BitsType> static inline bool bitsAreNaN(BitsType bits) {
-  using FPType = typename FloatType<BitsType>::Type;
-  return ((bits & BitPatterns<FPType>::inf) == BitPatterns<FPType>::inf) &&
-         ((bits & FloatProperties<FPType>::mantissaMask) != 0);
-}
-
-// Return true if x is a NAN (quiet or signalling.)
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline bool isNaN(T x) {
-  return bitsAreNaN(valueAsBits(x));
-}
-
-template <typename BitsType> static inline bool bitsAreInfOrNaN(BitsType bits) {
-  using FPType = typename FloatType<BitsType>::Type;
-  return (bits & BitPatterns<FPType>::inf) == BitPatterns<FPType>::inf;
-}
-
-template <typename BitsType> static inline bool bitsAreZero(BitsType bits) {
-  using FPType = typename FloatType<BitsType>::Type;
-  return (bits == BitPatterns<FPType>::zero) ||
-         (bits == BitPatterns<FPType>::negZero);
-}
-
-// Return true if x is any kind of NaN or infinity.
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline bool isInfOrNaN(T x) {
-  return bitsAreInfOrNaN(valueAsBits(x));
-}
-
-// Return true if x is a quiet NAN.
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline bool isQuietNaN(T x) {
-  using Properties = FloatProperties<T>;
-  using BitsType = typename FloatProperties<T>::BitsType;
-  BitsType bits = valueAsBits(x);
-  return ((bits & BitPatterns<T>::inf) == BitPatterns<T>::inf) &&
-         ((bits & Properties::quietNaNMask) != 0);
-}
-
-// Return true if x is a quiet NAN with sign bit set.
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline bool isNegativeQuietNaN(T x) {
-  using Properties = FloatProperties<T>;
-  using BitsType = typename FloatProperties<T>::BitsType;
-  BitsType bits = valueAsBits(x);
-  return ((bits & BitPatterns<T>::negInf) == BitPatterns<T>::negInf) &&
-         ((bits & Properties::quietNaNMask) != 0);
-}
-
-// Return the absolute value of x.
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T abs(T x) {
-  return valueFromBits(absBits(x));
-}
-
-// Return the trucated value of x. If x is non-negative, then the return value
-// is greatest integer less than or equal to x. Otherwise, return the smallest
-// integer greater than or equal to x. That is, return the integer value rounded
-// toward zero.
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T trunc(T x) {
-  using Properties = FloatProperties<T>;
-  using BitsType = typename FloatProperties<T>::BitsType;
-
-  BitsType bits = valueAsBits(x);
-
-  // If x is infinity, NaN or zero, return it.
-  if (bitsAreInfOrNaN(bits) || bitsAreZero(bits))
-    return x;
-
-  int exponent = getExponentFromBits(bits);
-
-  // If the exponent is greater than the most negative mantissa
-  // exponent, then x is already an integer.
-  if (exponent >= static_cast<int>(Properties::mantissaWidth))
-    return x;
-
-  // If the exponent is such that abs(x) is less than 1, then return 0.
-  if (exponent <= -1) {
-    if (Properties::signMask & bits)
-      return T(-0.0);
-    else
-      return T(0.0);
-  }
-
-  uint32_t trimSize = Properties::mantissaWidth - exponent;
-  return valueFromBits((bits >> trimSize) << trimSize);
-}
-
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T ceil(T x) {
-  using Properties = FloatProperties<T>;
-  using BitsType = typename FloatProperties<T>::BitsType;
-
-  BitsType bits = valueAsBits(x);
-
-  // If x is infinity NaN or zero, return it.
-  if (bitsAreInfOrNaN(bits) || bitsAreZero(bits))
-    return x;
-
-  bool isNeg = bits & Properties::signMask;
-  int exponent = getExponentFromBits(bits);
-
-  // If the exponent is greater than the most negative mantissa
-  // exponent, then x is already an integer.
-  if (exponent >= static_cast<int>(Properties::mantissaWidth))
-    return x;
-
-  if (exponent <= -1) {
-    if (isNeg)
-      return T(-0.0);
-    else
-      return T(1.0);
-  }
-
-  uint32_t trimSize = Properties::mantissaWidth - exponent;
-  // If x is already an integer, return it.
-  if ((bits << (Properties::bitWidth - trimSize)) == 0)
-    return x;
-
-  BitsType truncBits = (bits >> trimSize) << trimSize;
-  T truncValue = valueFromBits(truncBits);
-
-  // If x is negative, the ceil operation is equivalent to the trunc operation.
-  if (isNeg)
-    return truncValue;
-
-  return truncValue + T(1.0);
-}
-
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T floor(T x) {
-  auto bits = valueAsBits(x);
-  if (FloatProperties<T>::signMask & bits) {
-    return -ceil(-x);
-  } else {
-    return trunc(x);
-  }
-}
-
-template <typename T,
-          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
-static inline T round(T x) {
-  using Properties = FloatProperties<T>;
-  using BitsType = typename FloatProperties<T>::BitsType;
-
-  BitsType bits = valueAsBits(x);
-
-  // If x is infinity, NaN or zero, return it.
-  if (bitsAreInfOrNaN(bits) || bitsAreZero(bits))
-    return x;
-
-  bool isNeg = bits & Properties::signMask;
-  int exponent = getExponentFromBits(bits);
-
-  // If the exponent is greater than the most negative mantissa
-  // exponent, then x is already an integer.
-  if (exponent >= static_cast<int>(Properties::mantissaWidth))
-    return x;
-
-  if (exponent == -1) {
-    // Absolute value of x is greater than equal to 0.5 but less than 1.
-    if (isNeg)
-      return T(-1.0);
-    else
-      return T(1.0);
-  }
-
-  if (exponent <= -2) {
-    // Absolute value of x is less than 0.5.
-    if (isNeg)
-      return T(-0.0);
-    else
-      return T(0.0);
-  }
-
-  uint32_t trimSize = Properties::mantissaWidth - exponent;
-  // If x is already an integer, return it.
-  if ((bits << (Properties::bitWidth - trimSize)) == 0)
-    return x;
-
-  BitsType truncBits = (bits >> trimSize) << trimSize;
-  T truncValue = valueFromBits(truncBits);
-
-  if ((bits & (BitsType(1) << (trimSize - 1))) == 0) {
-    // Franctional part is less than 0.5 so round value is the
-    // same as the trunc value.
-    return truncValue;
-  }
-
-  if (isNeg)
-    return truncValue - T(1.0);
-  else
-    return truncValue + T(1.0);
-}
 
 } // namespace fputil
 } // namespace __llvm_libc
diff --git a/libc/utils/FPUtil/ManipulationFunctions.h b/libc/utils/FPUtil/ManipulationFunctions.h
index a59c0a7..b1e06f7 100644
--- a/libc/utils/FPUtil/ManipulationFunctions.h
+++ b/libc/utils/FPUtil/ManipulationFunctions.h
@@ -1,4 +1,4 @@
-//===-- Common operations on floating point numbers -------------*- C++ -*-===//
+//===-- Floating-point manipulation functions -------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
@@ -7,8 +7,10 @@
 //===----------------------------------------------------------------------===//
 
 #include "BitPatterns.h"
+#include "ClassificationFunctions.h"
 #include "FloatOperations.h"
 #include "FloatProperties.h"
+#include "NearestIntegerOperations.h"
 
 #include "utils/CPP/TypeTraits.h"
 
diff --git a/libc/utils/FPUtil/NearestIntegerOperations.h b/libc/utils/FPUtil/NearestIntegerOperations.h
new file mode 100644
index 0000000..7f93de6
--- /dev/null
+++ b/libc/utils/FPUtil/NearestIntegerOperations.h
@@ -0,0 +1,164 @@
+//===-- Nearest integer floating-point operations ---------------*- 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_UTILS_FPUTIL_NEAREST_INTEGER_OPERATIONS_H
+#define LLVM_LIBC_UTILS_FPUTIL_NEAREST_INTEGER_OPERATIONS_H
+
+#include "ClassificationFunctions.h"
+#include "FloatOperations.h"
+#include "FloatProperties.h"
+
+#include "utils/CPP/TypeTraits.h"
+
+namespace __llvm_libc {
+namespace fputil {
+
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline T trunc(T x) {
+  using Properties = FloatProperties<T>;
+  using BitsType = typename FloatProperties<T>::BitsType;
+
+  BitsType bits = valueAsBits(x);
+
+  // If x is infinity, NaN or zero, return it.
+  if (bitsAreInfOrNaN(bits) || bitsAreZero(bits))
+    return x;
+
+  int exponent = getExponentFromBits(bits);
+
+  // If the exponent is greater than the most negative mantissa
+  // exponent, then x is already an integer.
+  if (exponent >= static_cast<int>(Properties::mantissaWidth))
+    return x;
+
+  // If the exponent is such that abs(x) is less than 1, then return 0.
+  if (exponent <= -1) {
+    if (Properties::signMask & bits)
+      return T(-0.0);
+    else
+      return T(0.0);
+  }
+
+  uint32_t trimSize = Properties::mantissaWidth - exponent;
+  return valueFromBits((bits >> trimSize) << trimSize);
+}
+
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline T ceil(T x) {
+  using Properties = FloatProperties<T>;
+  using BitsType = typename FloatProperties<T>::BitsType;
+
+  BitsType bits = valueAsBits(x);
+
+  // If x is infinity NaN or zero, return it.
+  if (bitsAreInfOrNaN(bits) || bitsAreZero(bits))
+    return x;
+
+  bool isNeg = bits & Properties::signMask;
+  int exponent = getExponentFromBits(bits);
+
+  // If the exponent is greater than the most negative mantissa
+  // exponent, then x is already an integer.
+  if (exponent >= static_cast<int>(Properties::mantissaWidth))
+    return x;
+
+  if (exponent <= -1) {
+    if (isNeg)
+      return T(-0.0);
+    else
+      return T(1.0);
+  }
+
+  uint32_t trimSize = Properties::mantissaWidth - exponent;
+  // If x is already an integer, return it.
+  if ((bits << (Properties::bitWidth - trimSize)) == 0)
+    return x;
+
+  BitsType truncBits = (bits >> trimSize) << trimSize;
+  T truncValue = valueFromBits(truncBits);
+
+  // If x is negative, the ceil operation is equivalent to the trunc operation.
+  if (isNeg)
+    return truncValue;
+
+  return truncValue + T(1.0);
+}
+
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline T floor(T x) {
+  auto bits = valueAsBits(x);
+  if (FloatProperties<T>::signMask & bits) {
+    return -ceil(-x);
+  } else {
+    return trunc(x);
+  }
+}
+
+template <typename T,
+          cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
+static inline T round(T x) {
+  using Properties = FloatProperties<T>;
+  using BitsType = typename FloatProperties<T>::BitsType;
+
+  BitsType bits = valueAsBits(x);
+
+  // If x is infinity, NaN or zero, return it.
+  if (bitsAreInfOrNaN(bits) || bitsAreZero(bits))
+    return x;
+
+  bool isNeg = bits & Properties::signMask;
+  int exponent = getExponentFromBits(bits);
+
+  // If the exponent is greater than the most negative mantissa
+  // exponent, then x is already an integer.
+  if (exponent >= static_cast<int>(Properties::mantissaWidth))
+    return x;
+
+  if (exponent == -1) {
+    // Absolute value of x is greater than equal to 0.5 but less than 1.
+    if (isNeg)
+      return T(-1.0);
+    else
+      return T(1.0);
+  }
+
+  if (exponent <= -2) {
+    // Absolute value of x is less than 0.5.
+    if (isNeg)
+      return T(-0.0);
+    else
+      return T(0.0);
+  }
+
+  uint32_t trimSize = Properties::mantissaWidth - exponent;
+  // If x is already an integer, return it.
+  if ((bits << (Properties::bitWidth - trimSize)) == 0)
+    return x;
+
+  BitsType truncBits = (bits >> trimSize) << trimSize;
+  T truncValue = valueFromBits(truncBits);
+
+  if ((bits & (BitsType(1) << (trimSize - 1))) == 0) {
+    // Franctional part is less than 0.5 so round value is the
+    // same as the trunc value.
+    return truncValue;
+  }
+
+  if (isNeg)
+    return truncValue - T(1.0);
+  else
+    return truncValue + T(1.0);
+}
+
+} // namespace fputil
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_UTILS_FPUTIL_NEAREST_INTEGER_OPERATIONS_H