63 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			63 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===----------------------------------------------------------------------===//
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| //
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| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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| // See https://llvm.org/LICENSE.txt for license information.
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| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| // test unsigned long long to_ullong() const;
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| 
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| #include <bitset>
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| #include <algorithm>
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| #include <type_traits>
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| #include <climits>
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| #include <cassert>
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| 
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| #include "test_macros.h"
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| 
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| template <std::size_t N>
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| void test_to_ullong()
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| {
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|     const std::size_t M = sizeof(unsigned long long) * CHAR_BIT < N ? sizeof(unsigned long long) * CHAR_BIT : N;
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|     const bool is_M_zero = std::integral_constant<bool, M == 0>::value; // avoid compiler warnings
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|     const std::size_t X = is_M_zero ? sizeof(unsigned long long) * CHAR_BIT - 1 : sizeof(unsigned long long) * CHAR_BIT - M;
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|     const unsigned long long max = is_M_zero ? 0 : (unsigned long long)(-1) >> X;
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|     unsigned long long tests[] = {0,
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|                            std::min<unsigned long long>(1, max),
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|                            std::min<unsigned long long>(2, max),
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|                            std::min<unsigned long long>(3, max),
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|                            std::min(max, max-3),
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|                            std::min(max, max-2),
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|                            std::min(max, max-1),
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|                            max};
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|     for (std::size_t i = 0; i < sizeof(tests)/sizeof(tests[0]); ++i)
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|     {
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|         unsigned long long j = tests[i];
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|         std::bitset<N> v(j);
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|         assert(j == v.to_ullong());
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|     }
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|     { // test values bigger than can fit into the bitset
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|     const unsigned long long val = 0x55AAAAFFFFAAAA55ULL;
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|     const bool canFit = N < sizeof(unsigned long long) * CHAR_BIT;
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|     const unsigned long long mask = canFit ? (1ULL << (canFit ? N : 0)) - 1 : (unsigned long long)(-1); // avoid compiler warnings
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|     std::bitset<N> v(val);
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|     assert(v.to_ullong() == (val & mask)); // we shouldn't return bit patterns from outside the limits of the bitset.
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|     }
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| }
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| 
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| int main(int, char**)
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| {
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| //     test_to_ullong<0>();
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|     test_to_ullong<1>();
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|     test_to_ullong<31>();
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|     test_to_ullong<32>();
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|     test_to_ullong<33>();
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|     test_to_ullong<63>();
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|     test_to_ullong<64>();
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|     test_to_ullong<65>();
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|     test_to_ullong<1000>();
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| 
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|   return 0;
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| }
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