Move generate_phi.hpp code phi_vector.cpp (#74)

CMakeLists.txt

@@ -121,6 +121,7 @@ set(LIB_SRC src/api.cpp
             src/generate.cpp
             src/nth_prime.cpp
             src/phi.cpp
+            src/phi_vector.cpp
             src/pi_legendre.cpp
             src/pi_lehmer.cpp
             src/pi_meissel.cpp

ChangeLog

@@ -1,6 +1,7 @@
-Changes in primecount-7.14, 2024-06-22
+Changes in primecount-7.14, 2024-07-01
 
 * Move x86 cpuid code from cpuid.hpp to src/x86/cpuid.cpp.
+* Move generate_phi.hpp code to src/phi_vector.cpp.
 * int128_t.hpp: Rename namespace port to pstd (portable std namespace).
 * Sieve.hpp: Tune AVX512 code.
 * cpu_supports_popcnt.hpp: Simplify, move preprocessor checks to new multiarch_x86_popcnt.cmake.

include/phi_vector.hpp

@@ -0,0 +1,41 @@
+///
+/// @file  phi_vector.hpp
+///
+/// Copyright (C) 2024 Kim Walisch, <[email protected]>
+///
+/// This file is distributed under the BSD License. See the COPYING
+/// file in the top level directory.
+///
+
+#ifndef PHI_VECTOR_HPP
+#define PHI_VECTOR_HPP
+
+#include <PiTable.hpp>
+#include <Vector.hpp>
+#include <stdint.h>
+
+namespace primecount {
+
+/// Returns a vector with phi(x, i - 1) values such that
+/// phi[i] = phi(x, i - 1) for 1 <= i <= a.
+/// phi(x, a) counts the numbers <= x that are not
+/// divisible by any of the first a primes.
+///
+Vector<int64_t> phi_vector(int64_t x,
+                           int64_t a,
+                           const Vector<uint32_t>& primes,
+                           const PiTable& pi);
+
+/// Returns a vector with phi(x, i - 1) values such that
+/// phi[i] = phi(x, i - 1) for 1 <= i <= a.
+/// phi(x, a) counts the numbers <= x that are not
+/// divisible by any of the first a primes.
+///
+Vector<int64_t> phi_vector(int64_t x,
+                           int64_t a,
+                           const Vector<int64_t>& primes,
+                           const PiTable& pi);
+
+} // namespace
+
+#endif

src/deleglise-rivat/S2_hard.cpp

@@ -30,7 +30,7 @@
 #include <Sieve.hpp>
 #include <fast_div.hpp>
 #include <generate.hpp>
-#include <generate_phi.hpp>
+#include <phi_vector.hpp>
 #include <imath.hpp>
 #include <int128_t.hpp>
 #include <LoadBalancerS2.hpp>
@@ -83,7 +83,7 @@ T S2_hard_thread(T x,
   if (min_b > max_b)
     return 0;
 
-  auto phi = generate_phi(low, max_b, primes, pi);
+  Vector<int64_t> phi = phi_vector(low, max_b, primes, pi);
   Sieve sieve(low, segment_size, max_b);
   thread.init_finished();
 
@@ -254,7 +254,7 @@ int64_t S2_hard(int64_t x,
 
   FactorTable<uint16_t> factor(y, threads);
   int64_t max_prime = min(y, z / isqrt(y));
-  auto primes = generate_primes<int32_t>(max_prime);
+  auto primes = generate_primes<uint32_t>(max_prime);
   int64_t sum = S2_hard_OpenMP(x, y, z, c, s2_hard_approx, primes, factor, threads, is_print);
 
   if (is_print)

src/gourdon/D.cpp

@@ -28,7 +28,7 @@
 #include <LoadBalancerS2.hpp>
 #include <fast_div.hpp>
 #include <generate.hpp>
-#include <generate_phi.hpp>
+#include <phi_vector.hpp>
 #include <gourdon.hpp>
 #include <imath.hpp>
 #include <int128_t.hpp>
@@ -72,7 +72,7 @@ T D_thread(T x,
   if (min_b > max_b)
     return 0;
 
-  auto phi = generate_phi(low, max_b, primes, pi);
+  Vector<int64_t> phi = phi_vector(low, max_b, primes, pi);
   Sieve sieve(low, segment_size, max_b);
   thread.init_finished();
 
@@ -247,7 +247,7 @@ int64_t D(int64_t x,
   }
 
   FactorTableD<uint16_t> factor(y, z, threads);
-  auto primes = generate_primes<int32_t>(y);
+  auto primes = generate_primes<uint32_t>(y);
   int64_t sum = D_OpenMP(x, y, z, k, d_approx, primes, factor, threads, is_print);
 
   if (is_print)

src/lmo/pi_lmo_parallel.cpp

@@ -27,7 +27,7 @@
 #include <primecount-internal.hpp>
 #include <Sieve.hpp>
 #include <generate.hpp>
-#include <generate_phi.hpp>
+#include <phi_vector.hpp>
 #include <LoadBalancerS2.hpp>
 #include <min.hpp>
 #include <imath.hpp>
@@ -51,7 +51,7 @@ int64_t S2_thread(int64_t x,
                   int64_t z,
                   int64_t c,
                   const PiTable& pi,
-                  const Vector<int32_t>& primes,
+                  const Vector<uint32_t>& primes,
                   const Vector<int32_t>& lpf,
                   const Vector<int32_t>& mu,
                   ThreadData& thread)
@@ -70,7 +70,7 @@ int64_t S2_thread(int64_t x,
   if (min_b > max_b)
     return 0;
 
-  auto phi = generate_phi(low, max_b, primes, pi);
+  Vector<int64_t> phi = phi_vector(low, max_b, primes, pi);
   Sieve sieve(low, segment_size, max_b);
   thread.init_finished();
 
@@ -168,7 +168,7 @@ int64_t S2(int64_t x,
            int64_t z,
            int64_t c,
            int64_t s2_approx,
-           const Vector<int32_t>& primes,
+           const Vector<uint32_t>& primes,
            const Vector<int32_t>& lpf,
            const Vector<int32_t>& mu,
            int threads,
@@ -242,7 +242,7 @@ int64_t pi_lmo_parallel(int64_t x,
     print(x, y, z, c, threads);
   }
 
-  auto primes = generate_primes<int32_t>(y);
+  auto primes = generate_primes<uint32_t>(y);
   auto lpf = generate_lpf(y);
   auto mu = generate_moebius(y);
 

include/generate_phi.hpp → src/phi_vector.cpp

@@ -1,5 +1,5 @@
 ///
-/// @file  generate_phi.hpp
+/// @file  phi_vector.cpp
 /// @brief The PhiCache class calculates the partial sieve function
 ///        (a.k.a. Legendre-sum) using the recursive formula:
 ///        phi(x, a) = phi(x, a - 1) - phi(x / primes[a], a - 1).
@@ -22,9 +22,7 @@
 /// file in the top level directory.
 ///
 
-#ifndef GENERATE_PHI_HPP
-#define GENERATE_PHI_HPP
-
+#include <phi_vector.hpp>
 #include <primecount-internal.hpp>
 #include <BitSieve240.hpp>
 #include <fast_div.hpp>
@@ -40,7 +38,9 @@
 #include <algorithm>
 #include <utility>
 
-namespace primecount {
+namespace {
+
+using namespace primecount;
 
 template <typename Primes>
 class PhiCache : public BitSieve240
@@ -300,10 +300,10 @@ class PhiCache : public BitSieve240
 /// divisible by any of the first a primes.
 ///
 template <typename Primes>
-NOINLINE Vector<int64_t> generate_phi(int64_t x,
-                                      int64_t a,
-                                      const Primes& primes,
-                                      const PiTable& pi)
+Vector<int64_t> phi_vector(int64_t x,
+                           int64_t a,
+                           const Primes& primes,
+                           const PiTable& pi)
 {
   int64_t size = a + 1;
   Vector<int64_t> phi(size);
@@ -337,4 +337,32 @@ NOINLINE Vector<int64_t> generate_phi(int64_t x,
 
 } // namespace
 
-#endif
+namespace primecount {
+
+/// Returns a vector with phi(x, i - 1) values such that
+/// phi[i] = phi(x, i - 1) for 1 <= i <= a.
+/// phi(x, a) counts the numbers <= x that are not
+/// divisible by any of the first a primes.
+///
+Vector<int64_t> phi_vector(int64_t x,
+                           int64_t a,
+                           const Vector<uint32_t>& primes,
+                           const PiTable& pi)
+{
+  return ::phi_vector(x, a, primes, pi);
+}
+
+/// Returns a vector with phi(x, i - 1) values such that
+/// phi[i] = phi(x, i - 1) for 1 <= i <= a.
+/// phi(x, a) counts the numbers <= x that are not
+/// divisible by any of the first a primes.
+///
+Vector<int64_t> phi_vector(int64_t x,
+                           int64_t a,
+                           const Vector<int64_t>& primes,
+                           const PiTable& pi)
+{
+  return ::phi_vector(x, a, primes, pi);
+}
+
+} // namespace

test/generate_phi.cpp → test/phi_vector.cpp

@@ -1,17 +1,18 @@
 ///
-/// @file  generate_phi.cpp
-/// @brief Test that generate_phi(x, a) and phi(x, a)
+/// @file  phi_vector.cpp
+/// @brief Test that phi_vector(x, a) and phi(x, a)
 ///        results are identical
 ///
-/// Copyright (C) 2017 Kim Walisch, <[email protected]>
+/// Copyright (C) 2024 Kim Walisch, <[email protected]>
 ///
 /// This file is distributed under the BSD License. See the COPYING
 /// file in the top level directory.
 ///
 
 #include <primecount.hpp>
 #include <generate.hpp>
-#include <generate_phi.hpp>
+#include <imath.hpp>
+#include <phi_vector.hpp>
 #include <PiTable.hpp>
 
 #include <stdint.h>
@@ -38,7 +39,7 @@ int main()
     int64_t a = pi[y];
 
     auto primes = generate_primes<int64_t>(y);
-    auto phi_vect = generate_phi(x, a, primes, pi);
+    auto phi_vect = phi_vector(x, a, primes, pi);
 
     for (size_t i = 1; i < phi_vect.size(); i++)
     {
@@ -47,7 +48,7 @@ int main()
 
       if (phi1 != phi2)
       {
-        std::cerr << "Error: generate_phi(x, i - 1) = " << phi1 << std::endl;
+        std::cerr << "Error: phi_vector(x, i - 1) = " << phi1 << std::endl;
         std::cerr << "Correct: phi(x, i - 1) = " << phi2 << std::endl;
         std::cerr << "x = " << x << std::endl;
         std::cerr << "i - 1 = " << i - 1 << std::endl;