ClickHouse/dbms/src/Functions/minus.cpp
2019-01-23 04:56:53 +09:00

46 lines
1.3 KiB
C++

#include <Functions/FunctionFactory.h>
#include <Functions/FunctionBinaryArithmetic.h>
#include <common/arithmeticOverflow.h>
namespace DB
{
template <typename A, typename B>
struct MinusImpl
{
using ResultType = typename NumberTraits::ResultOfSubtraction<A, B>::Type;
static const constexpr bool allow_decimal = true;
template <typename Result = ResultType>
static inline NO_SANITIZE_UNDEFINED Result apply(A a, B b)
{
return static_cast<Result>(a) - b;
}
/// Apply operation and check overflow. It's used for Deciamal operations. @returns true if overflowed, false otherwise.
template <typename Result = ResultType>
static inline bool apply(A a, B b, Result & c)
{
return common::subOverflow(static_cast<Result>(a), b, c);
}
#if USE_EMBEDDED_COMPILER
static constexpr bool compilable = true;
static inline llvm::Value * compile(llvm::IRBuilder<> & b, llvm::Value * left, llvm::Value * right, bool)
{
return left->getType()->isIntegerTy() ? b.CreateSub(left, right) : b.CreateFSub(left, right);
}
#endif
};
struct NameMinus { static constexpr auto name = "minus"; };
using FunctionMinus = FunctionBinaryArithmetic<MinusImpl, NameMinus>;
void registerFunctionMinus(FunctionFactory & factory)
{
factory.registerFunction<FunctionMinus>();
}
}