ClickHouse/dbms/src/Functions/intDiv.h
alexey-milovidov e00ce0bb57
Every function in its own file, part 7 (#3666)
* Every function in its own file, part 7 [#CLICKHOUSE-2]

* Every function in its own file, part 7 [#CLICKHOUSE-2]

* Every function in its own file, part 7 [#CLICKHOUSE-2]

* Every function in its own file, part 7 [#CLICKHOUSE-2]

* Every function in its own file, part 7 [#CLICKHOUSE-2]

* Fixed build #3666
2018-11-26 19:20:40 +03:00

67 lines
1.5 KiB
C++

#pragma once
#include <type_traits>
#include <common/likely.h>
#include <Common/Exception.h>
#include <Common/config.h>
#include <DataTypes/NumberTraits.h>
namespace DB
{
namespace ErrorCodes
{
extern const int ILLEGAL_DIVISION;
}
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wsign-compare"
template <typename A, typename B>
inline void throwIfDivisionLeadsToFPE(A a, B b)
{
/// Is it better to use siglongjmp instead of checks?
if (unlikely(b == 0))
throw Exception("Division by zero", ErrorCodes::ILLEGAL_DIVISION);
/// http://avva.livejournal.com/2548306.html
if (unlikely(std::is_signed_v<A> && std::is_signed_v<B> && a == std::numeric_limits<A>::min() && b == -1))
throw Exception("Division of minimal signed number by minus one", ErrorCodes::ILLEGAL_DIVISION);
}
template <typename A, typename B>
inline bool divisionLeadsToFPE(A a, B b)
{
if (unlikely(b == 0))
return true;
if (unlikely(std::is_signed_v<A> && std::is_signed_v<B> && a == std::numeric_limits<A>::min() && b == -1))
return true;
return false;
}
#pragma GCC diagnostic pop
template <typename A, typename B>
struct DivideIntegralImpl
{
using ResultType = typename NumberTraits::ResultOfIntegerDivision<A, B>::Type;
template <typename Result = ResultType>
static inline Result apply(A a, B b)
{
throwIfDivisionLeadsToFPE(a, b);
return a / b;
}
#if USE_EMBEDDED_COMPILER
static constexpr bool compilable = false; /// don't know how to throw from LLVM IR
#endif
};
}