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This commit is contained in:
Nikita Vasilev 2019-08-04 16:03:38 +03:00
parent 53cc2b4856
commit 5d47a858c5
5 changed files with 38 additions and 25 deletions
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4
dbms/src/Functions/bitBoolMaskAnd.cpp
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@ -5,6 +5,10 @@
namespace DB
{
/// Working with UInt8: last bit = can be true, previous = can be false (Like dbms/src/Storages/MergeTree/BoolMask.h).
/// This function provides "AND" operation for BoolMasks.
/// Returns: "can be true" = A."can be true" AND B."can be true"
/// "can be false" = A."can be false" OR B."can be false"
template <typename A, typename B>
struct BitBoolMaskAndImpl
{

4
dbms/src/Functions/bitBoolMaskOr.cpp
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@ -5,6 +5,10 @@
namespace DB
{
/// Working with UInt8: last bit = can be true, previous = can be false (Like dbms/src/Storages/MergeTree/BoolMask.h).
/// This function provides "OR" operation for BoolMasks.
/// Returns: "can be true" = A."can be true" OR B."can be true"
/// "can be false" = A."can be false" AND B."can be false"
template <typename A, typename B>
struct BitBoolMaskOrImpl
{

48
dbms/src/Functions/bitSwapLastTwo.cpp
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@ -5,16 +5,18 @@
namespace DB
{
template <typename A>
struct BitSwapLastTwoImpl
{
using ResultType = UInt8;
static inline ResultType NO_SANITIZE_UNDEFINED apply(A a)
/// Working with UInt8: last bit = can be true, previous = can be false (Like dbms/src/Storages/MergeTree/BoolMask.h).
/// This function provides "NOT" operation for BoolMasks by swapping last two bits ("can be true" <-> "can be false").
template <typename A>
struct BitSwapLastTwoImpl
{
return static_cast<ResultType>(
((static_cast<ResultType>(a) & 1) << 1) | ((static_cast<ResultType>(a) >> 1) & 1));
}
using ResultType = UInt8;
static inline ResultType NO_SANITIZE_UNDEFINED apply(A a)
{
return static_cast<ResultType>(
((static_cast<ResultType>(a) & 1) << 1) | ((static_cast<ResultType>(a) >> 1) & 1));
}
#if USE_EMBEDDED_COMPILER
static constexpr bool compilable = true;
@ -29,23 +31,23 @@ struct BitSwapLastTwoImpl
);
}
#endif
};
};
struct NameBitSwapLastTwo { static constexpr auto name = "__bitSwapLastTwo"; };
using FunctionBitSwapLastTwo = FunctionUnaryArithmetic<BitSwapLastTwoImpl, NameBitSwapLastTwo, true>;
struct NameBitSwapLastTwo { static constexpr auto name = "__bitSwapLastTwo"; };
using FunctionBitSwapLastTwo = FunctionUnaryArithmetic<BitSwapLastTwoImpl, NameBitSwapLastTwo, true>;
template <> struct FunctionUnaryArithmeticMonotonicity<NameBitSwapLastTwo>
{
static bool has() { return false; }
static IFunction::Monotonicity get(const Field &, const Field &)
template <> struct FunctionUnaryArithmeticMonotonicity<NameBitSwapLastTwo>
{
return {};
static bool has() { return false; }
static IFunction::Monotonicity get(const Field &, const Field &)
{
return {};
}
};
void registerFunctionBitSwapLastTwo(FunctionFactory & factory)
{
factory.registerFunction<FunctionBitSwapLastTwo>();
}
};
void registerFunctionBitSwapLastTwo(FunctionFactory & factory)
{
factory.registerFunction<FunctionBitSwapLastTwo>();
}
}

3
dbms/src/Functions/bitWrapperFunc.cpp
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@ -5,6 +5,9 @@
namespace DB
{
/// Working with UInt8: last bit = can be true, previous = can be false (Like dbms/src/Storages/MergeTree/BoolMask.h).
/// This function wraps bool atomic functions
/// and transforms their boolean return value to the BoolMask ("can be false" and "can be true" bits).
template <typename A>
struct BitWrapperFuncImpl
{

4
dbms/src/Storages/MergeTree/MergeTreeIndexSet.cpp
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@ -227,8 +227,6 @@ MergeTreeIndexConditionSet::MergeTreeIndexConditionSet(
const auto & select = query.query->as<ASTSelectQuery &>();
/// Replace logical functions with bit functions.
/// Working with UInt8: last bit = can be true, previous = can be false.
if (select.where() && select.prewhere())
expression_ast = makeASTFunction(
"and",
@ -246,6 +244,8 @@ MergeTreeIndexConditionSet::MergeTreeIndexConditionSet(
if (useless)
return;
/// Replace logical functions with bit functions.
/// Working with UInt8: last bit = can be true, previous = can be false (Like dbms/src/Storages/MergeTree/BoolMask.h).
traverseAST(expression_ast);
auto syntax_analyzer_result = SyntaxAnalyzer(context, {}).analyze(