[libc][NFC] Move Sign type to separate header (llvm#85930)

libc/src/__support/CMakeLists.txt

@@ -41,6 +41,14 @@ add_header_library(
     libc.src.__support.macros.config
 )
 
+add_header_library(
+  sign
+  HDRS
+    sign.h
+  DEPENDS
+    libc.src.__support.macros.attributes
+)
+
 add_header_library(
   error_or
   HDRS

libc/src/__support/FPUtil/CMakeLists.txt

@@ -35,6 +35,7 @@ add_header_library(
     libc.src.__support.macros.attributes
     libc.src.__support.macros.properties.types
     libc.src.__support.math_extras
+    libc.src.__support.sign
     libc.src.__support.uint128
 )
 

libc/src/__support/FPUtil/FPBits.h

@@ -17,6 +17,7 @@
 #include "src/__support/macros/attributes.h" // LIBC_INLINE, LIBC_INLINE_VAR
 #include "src/__support/macros/properties/types.h" // LIBC_TYPES_HAS_FLOAT128
 #include "src/__support/math_extras.h"             // mask_trailing_ones
+#include "src/__support/sign.h"                    // Sign
 
 #include <stdint.h>
 
@@ -32,32 +33,6 @@ enum class FPType {
   X86_Binary80,
 };
 
-// A type to interact with floating point type signs.
-// This may be moved outside of 'fputil' if useful.
-struct Sign {
-  LIBC_INLINE constexpr bool is_pos() const { return !is_negative; }
-  LIBC_INLINE constexpr bool is_neg() const { return is_negative; }
-
-  LIBC_INLINE friend constexpr bool operator==(Sign a, Sign b) {
-    return a.is_negative == b.is_negative;
-  }
-  LIBC_INLINE friend constexpr bool operator!=(Sign a, Sign b) {
-    return !(a == b);
-  }
-
-  static const Sign POS;
-  static const Sign NEG;
-
-private:
-  LIBC_INLINE constexpr explicit Sign(bool is_negative)
-      : is_negative(is_negative) {}
-
-  bool is_negative;
-};
-
-LIBC_INLINE_VAR constexpr Sign Sign::NEG = Sign(true);
-LIBC_INLINE_VAR constexpr Sign Sign::POS = Sign(false);
-
 // The classes hierarchy is as follows:
 //
 //             ┌───────────────────┐

libc/src/__support/FPUtil/fpbits_str.h

@@ -35,7 +35,6 @@ using ZeroPaddedHexFmt = IntegerToString<
 //    floating encoding.
 template <typename T> LIBC_INLINE cpp::string str(fputil::FPBits<T> x) {
   using StorageType = typename fputil::FPBits<T>::StorageType;
-  using Sign = fputil::Sign;
 
   if (x.is_nan())
     return "(NaN)";

libc/src/__support/sign.h

@@ -0,0 +1,40 @@
+//===-- A simple sign type --------------------------------------*- 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_SIGN_H
+#define LLVM_LIBC_SRC___SUPPORT_SIGN_H
+
+#include "src/__support/macros/attributes.h" // LIBC_INLINE, LIBC_INLINE_VAR
+
+// A type to interact with signed arithmetic types.
+struct Sign {
+  LIBC_INLINE constexpr bool is_pos() const { return !is_negative; }
+  LIBC_INLINE constexpr bool is_neg() const { return is_negative; }
+
+  LIBC_INLINE friend constexpr bool operator==(Sign a, Sign b) {
+    return a.is_negative == b.is_negative;
+  }
+
+  LIBC_INLINE friend constexpr bool operator!=(Sign a, Sign b) {
+    return !(a == b);
+  }
+
+  static const Sign POS;
+  static const Sign NEG;
+
+private:
+  LIBC_INLINE constexpr explicit Sign(bool is_negative)
+      : is_negative(is_negative) {}
+
+  bool is_negative;
+};
+
+LIBC_INLINE_VAR constexpr Sign Sign::NEG = Sign(true);
+LIBC_INLINE_VAR constexpr Sign Sign::POS = Sign(false);
+
+#endif // LLVM_LIBC_SRC___SUPPORT_SIGN_H

libc/src/__support/str_to_float.h

@@ -513,7 +513,6 @@ clinger_fast_path(ExpandedFloat<T> init_num,
                   RoundDirection round = RoundDirection::Nearest) {
   using FPBits = typename fputil::FPBits<T>;
   using StorageType = typename FPBits::StorageType;
-  using Sign = fputil::Sign;
 
   StorageType mantissa = init_num.mantissa;
   int32_t exp10 = init_num.exponent;
@@ -1085,7 +1084,6 @@ template <class T>
 LIBC_INLINE StrToNumResult<T> strtofloatingpoint(const char *__restrict src) {
   using FPBits = typename fputil::FPBits<T>;
   using StorageType = typename FPBits::StorageType;
-  using Sign = fputil::Sign;
 
   FPBits result = FPBits();
   bool seen_digit = false;
@@ -1223,7 +1221,7 @@ template <class T> LIBC_INLINE StrToNumResult<T> strtonan(const char *arg) {
   if (arg[index] == '\0')
     nan_mantissa = nan_mantissa_from_ncharseq<T>(cpp::string_view(arg, index));
 
-  result = FPBits::quiet_nan(fputil::Sign::POS, nan_mantissa);
+  result = FPBits::quiet_nan(Sign::POS, nan_mantissa);
   return {result.get_val(), 0, error};
 }
 

libc/src/math/generic/acosf.cpp

@@ -38,7 +38,7 @@ static constexpr fputil::ExceptValues<float, N_EXCEPTS> ACOSF_EXCEPTS = {{
 
 LLVM_LIBC_FUNCTION(float, acosf, (float x)) {
   using FPBits = typename fputil::FPBits<float>;
-  using Sign = fputil::Sign;
+
   FPBits xbits(x);
   uint32_t x_uint = xbits.uintval();
   uint32_t x_abs = xbits.uintval() & 0x7fff'ffffU;

libc/src/math/generic/asinf.cpp

@@ -44,7 +44,7 @@ static constexpr fputil::ExceptValues<float, N_EXCEPTS> ASINF_EXCEPTS_HI = {{
 
 LLVM_LIBC_FUNCTION(float, asinf, (float x)) {
   using FPBits = typename fputil::FPBits<float>;
-  using Sign = fputil::Sign;
+
   FPBits xbits(x);
   uint32_t x_uint = xbits.uintval();
   uint32_t x_abs = xbits.uintval() & 0x7fff'ffffU;

libc/src/math/generic/atanf.cpp

@@ -20,7 +20,6 @@ namespace LIBC_NAMESPACE {
 
 LLVM_LIBC_FUNCTION(float, atanf, (float x)) {
   using FPBits = typename fputil::FPBits<float>;
-  using Sign = fputil::Sign;
 
   constexpr double FINAL_SIGN[2] = {1.0, -1.0};
   constexpr double SIGNED_PI_OVER_2[2] = {0x1.921fb54442d18p0,

libc/src/math/generic/atanhf.cpp

@@ -15,7 +15,7 @@ namespace LIBC_NAMESPACE {
 
 LLVM_LIBC_FUNCTION(float, atanhf, (float x)) {
   using FPBits = typename fputil::FPBits<float>;
-  using Sign = fputil::Sign;
+
   FPBits xbits(x);
   Sign sign = xbits.sign();
   uint32_t x_abs = xbits.abs().uintval();

libc/src/math/generic/cosf.cpp

@@ -42,7 +42,7 @@ static constexpr fputil::ExceptValues<float, N_EXCEPTS> COSF_EXCEPTS{{
 
 LLVM_LIBC_FUNCTION(float, cosf, (float x)) {
   using FPBits = typename fputil::FPBits<float>;
-  using Sign = fputil::Sign;
+
   FPBits xbits(x);
   xbits.set_sign(Sign::POS);
 

libc/src/math/generic/coshf.cpp

@@ -17,7 +17,7 @@ namespace LIBC_NAMESPACE {
 
 LLVM_LIBC_FUNCTION(float, coshf, (float x)) {
   using FPBits = typename fputil::FPBits<float>;
-  using Sign = fputil::Sign;
+
   FPBits xbits(x);
   xbits.set_sign(Sign::POS);
   x = xbits.get_val();

libc/src/math/generic/exp.cpp

@@ -31,7 +31,7 @@ namespace LIBC_NAMESPACE {
 using fputil::DoubleDouble;
 using fputil::TripleDouble;
 using Float128 = typename fputil::DyadicFloat<128>;
-using Sign = fputil::Sign;
+
 using LIBC_NAMESPACE::operator""_u128;
 
 // log2(e)

libc/src/math/generic/exp10.cpp

@@ -31,7 +31,7 @@ namespace LIBC_NAMESPACE {
 using fputil::DoubleDouble;
 using fputil::TripleDouble;
 using Float128 = typename fputil::DyadicFloat<128>;
-using Sign = fputil::Sign;
+
 using LIBC_NAMESPACE::operator""_u128;
 
 // log2(10)

libc/src/math/generic/exp2.cpp

@@ -31,7 +31,7 @@ namespace LIBC_NAMESPACE {
 using fputil::DoubleDouble;
 using fputil::TripleDouble;
 using Float128 = typename fputil::DyadicFloat<128>;
-using Sign = fputil::Sign;
+
 using LIBC_NAMESPACE::operator""_u128;
 
 // Error bounds:

libc/src/math/generic/expm1.cpp

@@ -39,7 +39,7 @@ namespace LIBC_NAMESPACE {
 using fputil::DoubleDouble;
 using fputil::TripleDouble;
 using Float128 = typename fputil::DyadicFloat<128>;
-using Sign = fputil::Sign;
+
 using LIBC_NAMESPACE::operator""_u128;
 
 // log2(e)
@@ -276,7 +276,7 @@ double set_exceptional(double x) {
 
 LLVM_LIBC_FUNCTION(double, expm1, (double x)) {
   using FPBits = typename fputil::FPBits<double>;
-  using Sign = fputil::Sign;
+
   FPBits xbits(x);
 
   bool x_is_neg = xbits.is_neg();

libc/src/math/generic/log.cpp

@@ -24,7 +24,7 @@ namespace LIBC_NAMESPACE {
 
 // 128-bit precision dyadic floating point numbers.
 using Float128 = typename fputil::DyadicFloat<128>;
-using Sign = fputil::Sign;
+
 using LIBC_NAMESPACE::operator""_u128;
 
 namespace {
@@ -735,7 +735,7 @@ double log_accurate(int e_x, int index, double m_x) {
 
 LLVM_LIBC_FUNCTION(double, log, (double x)) {
   using FPBits_t = typename fputil::FPBits<double>;
-  using Sign = fputil::Sign;
+
   FPBits_t xbits(x);
   uint64_t x_u = xbits.uintval();
 

libc/src/math/generic/log10.cpp

@@ -24,7 +24,7 @@ namespace LIBC_NAMESPACE {
 
 // 128-bit precision dyadic floating point numbers.
 using Float128 = typename fputil::DyadicFloat<128>;
-using Sign = fputil::Sign;
+
 using LIBC_NAMESPACE::operator""_u128;
 
 namespace {
@@ -737,7 +737,7 @@ double log10_accurate(int e_x, int index, double m_x) {
 
 LLVM_LIBC_FUNCTION(double, log10, (double x)) {
   using FPBits_t = typename fputil::FPBits<double>;
-  using Sign = fputil::Sign;
+
   FPBits_t xbits(x);
   uint64_t x_u = xbits.uintval();
 

libc/src/math/generic/log10f.cpp

@@ -106,7 +106,7 @@ LLVM_LIBC_FUNCTION(float, log10f, (float x)) {
   constexpr double LOG10_2 = 0x1.34413509f79ffp-2;
 
   using FPBits = typename fputil::FPBits<float>;
-  using Sign = fputil::Sign;
+
   FPBits xbits(x);
   uint32_t x_u = xbits.uintval();
 

libc/src/math/generic/log1p.cpp

@@ -23,7 +23,7 @@ namespace LIBC_NAMESPACE {
 
 // 128-bit precision dyadic floating point numbers.
 using Float128 = typename fputil::DyadicFloat<128>;
-using Sign = fputil::Sign;
+
 using LIBC_NAMESPACE::operator""_u128;
 
 namespace {
@@ -877,7 +877,7 @@ LIBC_INLINE double log1p_accurate(int e_x, int index,
 
 LLVM_LIBC_FUNCTION(double, log1p, (double x)) {
   using FPBits_t = typename fputil::FPBits<double>;
-  using Sign = fputil::Sign;
+
   constexpr int EXP_BIAS = FPBits_t::EXP_BIAS;
   constexpr int FRACTION_LEN = FPBits_t::FRACTION_LEN;
   constexpr uint64_t FRACTION_MASK = FPBits_t::FRACTION_MASK;

libc/src/math/generic/log1pf.cpp

@@ -106,7 +106,7 @@ LLVM_LIBC_FUNCTION(float, log1pf, (float x)) {
     case 0xbf800000U: // x = -1.0
       fputil::set_errno_if_required(ERANGE);
       fputil::raise_except_if_required(FE_DIVBYZERO);
-      return FPBits::inf(fputil::Sign::NEG).get_val();
+      return FPBits::inf(Sign::NEG).get_val();
 #ifndef LIBC_TARGET_CPU_HAS_FMA
     case 0x4cc1c80bU: // x = 0x1.839016p+26f
       return fputil::round_result_slightly_down(0x1.26fc04p+4f);

libc/src/math/generic/log2.cpp

@@ -24,7 +24,7 @@ namespace LIBC_NAMESPACE {
 
 // 128-bit precision dyadic floating point numbers.
 using Float128 = typename fputil::DyadicFloat<128>;
-using Sign = fputil::Sign;
+
 using LIBC_NAMESPACE::operator""_u128;
 
 namespace {
@@ -857,7 +857,7 @@ double log2_accurate(int e_x, int index, double m_x) {
 
 LLVM_LIBC_FUNCTION(double, log2, (double x)) {
   using FPBits_t = typename fputil::FPBits<double>;
-  using Sign = fputil::Sign;
+
   FPBits_t xbits(x);
   uint64_t x_u = xbits.uintval();
 

libc/src/math/generic/log2f.cpp

@@ -55,7 +55,7 @@ namespace LIBC_NAMESPACE {
 
 LLVM_LIBC_FUNCTION(float, log2f, (float x)) {
   using FPBits = typename fputil::FPBits<float>;
-  using Sign = fputil::Sign;
+
   FPBits xbits(x);
   uint32_t x_u = xbits.uintval();
 

libc/src/math/generic/log_range_reduction.h

@@ -37,7 +37,6 @@ log_range_reduction(double m_x, const LogRR &log_table,
                     fputil::DyadicFloat<128> &sum) {
   using Float128 = typename fputil::DyadicFloat<128>;
   using MType = typename Float128::MantissaType;
-  using Sign = fputil::Sign;
 
   int64_t v = static_cast<int64_t>(m_x * 0x1.0p60); // ulp = 2^-60
 

libc/src/math/generic/logf.cpp

@@ -54,7 +54,7 @@ namespace LIBC_NAMESPACE {
 LLVM_LIBC_FUNCTION(float, logf, (float x)) {
   constexpr double LOG_2 = 0x1.62e42fefa39efp-1;
   using FPBits = typename fputil::FPBits<float>;
-  using Sign = fputil::Sign;
+
   FPBits xbits(x);
   uint32_t x_u = xbits.uintval();
 

libc/src/math/generic/powf.cpp

@@ -424,7 +424,7 @@ LIBC_INLINE bool larger_exponent(double a, double b) {
 double powf_double_double(int idx_x, double dx, double y6, double lo6_hi,
                           const DoubleDouble &exp2_hi_mid) {
   using DoubleBits = typename fputil::FPBits<double>;
-  using Sign = fputil::Sign;
+
   // Perform a second range reduction step:
   //   idx2 = round(2^14 * (dx  + 2^-8)) = round ( dx * 2^14 + 2^6)
   //   dx2 = (1 + dx) * r2 - 1
@@ -513,7 +513,7 @@ double powf_double_double(int idx_x, double dx, double y6, double lo6_hi,
 LLVM_LIBC_FUNCTION(float, powf, (float x, float y)) {
   using FloatBits = typename fputil::FPBits<float>;
   using DoubleBits = typename fputil::FPBits<double>;
-  using Sign = fputil::Sign;
+
   FloatBits xbits(x), ybits(y);
 
   uint32_t x_u = xbits.uintval();

libc/src/stdio/printf_core/float_dec_converter.h

@@ -48,7 +48,7 @@ constexpr uint32_t MAX_BLOCK = 999999999;
 constexpr char DECIMAL_POINT = '.';
 
 LIBC_INLINE RoundDirection get_round_direction(int last_digit, bool truncated,
-                                               fputil::Sign sign) {
+                                               Sign sign) {
   switch (fputil::quick_get_round()) {
   case FE_TONEAREST:
     // Round to nearest, if it's exactly halfway then round to even.

libc/test/UnitTest/FPMatcher.h

@@ -63,7 +63,6 @@ template <TestCond C, typename T> FPMatcher<T, C> getMatcher(T expectedValue) {
 template <typename T> struct FPTest : public Test {
   using FPBits = LIBC_NAMESPACE::fputil::FPBits<T>;
   using StorageType = typename FPBits::StorageType;
-  using Sign = LIBC_NAMESPACE::fputil::Sign;
   static constexpr StorageType STORAGE_MAX =
       LIBC_NAMESPACE::cpp::numeric_limits<StorageType>::max();
   static constexpr T zero = FPBits::zero(Sign::POS).get_val();
@@ -92,7 +91,7 @@ template <typename T> struct FPTest : public Test {
 #define DECLARE_SPECIAL_CONSTANTS(T)                                           \
   using FPBits = LIBC_NAMESPACE::fputil::FPBits<T>;                            \
   using StorageType = typename FPBits::StorageType;                            \
-  using Sign = LIBC_NAMESPACE::fputil::Sign;                                   \
+                                                                               \
   static constexpr StorageType STORAGE_MAX =                                   \
       LIBC_NAMESPACE::cpp::numeric_limits<StorageType>::max();                 \
   const T zero = FPBits::zero(Sign::POS).get_val();                            \