cyb70289 commented on a change in pull request #10530:
URL: https://github.com/apache/arrow/pull/10530#discussion_r651405645
##########
File path: cpp/src/arrow/compute/kernels/scalar_arithmetic.cc
##########
@@ -397,6 +397,130 @@ struct PowerChecked {
}
};
+// Bitwise operations
+
+struct BitWiseNot {
+ template <typename T, typename Arg>
+ static T Call(KernelContext*, Arg arg, Status*) {
+ return ~arg;
+ }
+};
+
+struct BitWiseAnd {
+ template <typename T, typename Arg0, typename Arg1>
+ static T Call(KernelContext*, Arg0 lhs, Arg1 rhs, Status*) {
+ return lhs & rhs;
+ }
+};
+
+struct BitWiseOr {
+ template <typename T, typename Arg0, typename Arg1>
+ static T Call(KernelContext*, Arg0 lhs, Arg1 rhs, Status*) {
+ return lhs | rhs;
+ }
+};
+
+struct BitWiseXor {
+ template <typename T, typename Arg0, typename Arg1>
+ static T Call(KernelContext*, Arg0 lhs, Arg1 rhs, Status*) {
+ return lhs ^ rhs;
+ }
+};
+
+struct ShiftLeftLogical {
+ template <typename T, typename Arg0, typename Arg1>
+ static T Call(KernelContext*, Arg0 lhs, Arg1 rhs, Status*) {
+ static_assert(std::is_same<T, Arg0>::value, "");
+ return lhs << rhs;
+ }
+};
+
+// See SEI CERT C Coding Standard rule INT34-C
+struct ShiftLeftLogicalChecked {
+ template <typename T, typename Arg0, typename Arg1>
+ static enable_if_unsigned_integer<T> Call(KernelContext*, Arg0 lhs, Arg1 rhs,
+ Status* st) {
+ static_assert(std::is_same<T, Arg0>::value, "");
+ if (ARROW_PREDICT_FALSE(rhs < 0)) {
+ *st = Status::Invalid("Both operands must be non-negative");
+ return lhs;
+ }
+ if (ARROW_PREDICT_FALSE(rhs >= std::numeric_limits<Arg0>::digits)) {
+ *st = Status::Invalid("overflow");
+ return lhs;
+ }
+ return lhs << rhs;
+ }
+
+ template <typename T, typename Arg0, typename Arg1>
+ static enable_if_signed_integer<T> Call(KernelContext*, Arg0 lhs, Arg1 rhs,
+ Status* st) {
+ static_assert(std::is_same<T, Arg0>::value, "");
+ if (ARROW_PREDICT_FALSE(lhs < 0 || rhs < 0)) {
+ *st = Status::Invalid("Both operands must be non-negative");
+ return lhs;
+ }
+ if (ARROW_PREDICT_FALSE(rhs >= std::numeric_limits<Arg0>::digits)) {
+ *st = Status::Invalid("overflow");
+ return lhs;
+ }
+ if (ARROW_PREDICT_FALSE(lhs > (std::numeric_limits<Arg0>::max() >> rhs))) {
+ *st = Status::Invalid("overflow");
+ return lhs;
+ }
+ return lhs << rhs;
+ }
+};
+
+struct ShiftRightArithmetic {
+ template <typename T, typename Arg0, typename Arg1>
+ static T Call(KernelContext*, Arg0 lhs, Arg1 rhs, Status*) {
+ using Signed = typename std::make_signed<Arg0>::type;
+ static_assert(std::is_same<T, Arg0>::value, "");
+ // N.B. this is implementation-defined but GCC and MSVC document
+ // this as arithmetic right shift. References:
+ //
https://gcc.gnu.org/onlinedocs/gcc/Integers-implementation.html#Integers-implementation
+ //
https://docs.microsoft.com/en-us/cpp/cpp/left-shift-and-right-shift-operators-input-and-output?view=msvc-160#right-shifts
+ // Clang doesn't document their behavior.
+ return static_cast<T>(static_cast<Signed>(lhs) >> rhs);
Review comment:
For unsigned char 128, arithmetic right shift 1 bit results to 192,
looks a bit surprising.
Looks arithmetic right shift is more meaningful for signed integers, and
logical right shift for unsigned integers.
##########
File path: cpp/src/arrow/compute/kernels/scalar_arithmetic.cc
##########
@@ -397,6 +397,130 @@ struct PowerChecked {
}
};
+// Bitwise operations
+
+struct BitWiseNot {
+ template <typename T, typename Arg>
+ static T Call(KernelContext*, Arg arg, Status*) {
+ return ~arg;
+ }
+};
+
+struct BitWiseAnd {
+ template <typename T, typename Arg0, typename Arg1>
+ static T Call(KernelContext*, Arg0 lhs, Arg1 rhs, Status*) {
+ return lhs & rhs;
+ }
+};
+
+struct BitWiseOr {
+ template <typename T, typename Arg0, typename Arg1>
+ static T Call(KernelContext*, Arg0 lhs, Arg1 rhs, Status*) {
+ return lhs | rhs;
+ }
+};
+
+struct BitWiseXor {
+ template <typename T, typename Arg0, typename Arg1>
+ static T Call(KernelContext*, Arg0 lhs, Arg1 rhs, Status*) {
+ return lhs ^ rhs;
+ }
+};
+
+struct ShiftLeftLogical {
+ template <typename T, typename Arg0, typename Arg1>
+ static T Call(KernelContext*, Arg0 lhs, Arg1 rhs, Status*) {
+ static_assert(std::is_same<T, Arg0>::value, "");
+ return lhs << rhs;
Review comment:
Though it's not a checked kernel, I think it's still necessary to make
sure no UB can happen.
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