STYLE: add constexpr to PackedList methods

2025-11-28 03:28:01 +00:00 · 2018-01-04 19:16:15 +01:00
parent f868b11a31
commit 85eb441bea
6 changed files with 151 additions and 16 deletions
--- a/applications/test/bitops/Test-bitops.C
+++ b/applications/test/bitops/Test-bitops.C
@ -0,0 +1,124 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+Description
+    Test some bit-operations.
+
+\*---------------------------------------------------------------------------*/
+
+#include "bool.H"
+#include "IOstreams.H"
+
+#include <algorithm>
+#include <type_traits>
+#include <limits>
+
+template<typename UIntType, UIntType v, unsigned int n>
+struct set_lower_bits
+:
+    public std::integral_constant
+    <
+        UIntType,
+        v | (v >> n) | set_lower_bits<UIntType, v | (v >> n), (n >> 1)>::value
+    >
+{};
+
+
+template<typename UIntType, UIntType v>
+struct set_lower_bits<UIntType, v, 1>
+:
+    public std::integral_constant<UIntType, v | (v >> 1)>
+{};
+
+
+template<typename UIntType, UIntType v>
+struct pow2ceil
+:
+    public std::integral_constant
+    <
+        UIntType,
+        set_lower_bits
+        <
+            UIntType,
+            v - 1,
+            (std::numeric_limits<UIntType>::digits >> 1)
+        >::value + 1
+    >
+{};
+
+
+// No quite
+template<size_t N>
+struct topbit : std::integral_constant<size_t, topbit<(N >> 1)>{} + 1> {};
+
+template<> struct topbit<1> : std::integral_constant<size_t,1> {};
+template<> struct topbit<0> : std::integral_constant<size_t,0> {};
+
+using namespace Foam;
+
+
+template<size_t N>
+void printTopbit()
+{
+    std::cout
+        <<"topbit<" << N << "> : " << topbit<N>::value << '\n';
+}
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+int main(int argc, char *argv[])
+{
+    Info<<"pow2ceil<10>: "
+        << pow2ceil<unsigned, 10>::value << nl;
+
+    Info<<"pow2ceil<16>: "
+        << pow2ceil<unsigned, 16>::value << nl;
+
+    Info<<"pow2ceil<369>: "
+        << pow2ceil<unsigned, 369>::value << nl;
+
+    printTopbit<0>();
+    printTopbit<1>();
+    printTopbit<2>();
+    printTopbit<3>();
+    printTopbit<4>();
+    printTopbit<5>();
+    printTopbit<6>();
+    printTopbit<7>();
+    printTopbit<8>();
+    printTopbit<9>();
+    printTopbit<10>();
+    printTopbit<11>();
+    printTopbit<15>();
+    printTopbit<16>();
+    printTopbit<17>();
+    printTopbit<18>();
+
+    Info << "---\nEnd\n" << endl;
+
+    return 0;
+}
+
+
+// ************************************************************************* //