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[2] [3] Right-shifting a negative value is implementation-defined and not recommended by good coding practice; [4] the result of left-shifting a signed value is undefined if the result cannot be represented in the result type. [2] In C#, the right-shift is an arithmetic shift when the first operand is an int or long.
In computer science, a logical shift is a bitwise operation that shifts all the bits of its operand. The two base variants are the logical left shift and the logical right shift . This is further modulated by the number of bit positions a given value shall be shifted, such as shift left by 1 or shift right by n .
Bitwise operations are contrasted by byte-level operations which characterize the bitwise operators' logical counterparts, the AND, OR, NOT operators. Instead of performing on individual bits, byte-level operators perform on strings of eight bits (known as bytes) at a time.
The two basic types are the arithmetic left shift and the arithmetic right shift. For binary numbers it is a bitwise operation that shifts all of the bits of its operand; every bit in the operand is simply moved a given number of bit positions, and the vacant bit-positions are filled in.
A bitwise operation operates on one or more bit patterns or binary numerals at the level of their individual bits. It is a fast, primitive action directly supported by the central processing unit (CPU), and is used to manipulate values for comparisons and calculations.
In many programming languages, the vertical bar is used to designate the logic operation or, either bitwise or or logical or. Specifically, in C and other languages following C syntax conventions, such as C++, Perl, Java and C#, a | b denotes a bitwise or; whereas a double vertical bar a || b denotes a (short-circuited) logical or.
Shift an integer left (shifting in zeros), return an integer. Base instruction 0x63 shr: Shift an integer right (shift in sign), return an integer. Base instruction 0x64 shr.un: Shift an integer right (shift in zero), return an integer. Base instruction 0xFE 0x1C sizeof <typeTok> Push the size, in bytes, of a type as an unsigned int32.
In C/C++ bitwise shifting a value by a number of bits which is either a negative number or is greater than or equal to the total number of bits in this value results in undefined behavior. The safest way (regardless of compiler vendor) is to always keep the number of bits to shift (the right operand of the << and >> bitwise operators ) within ...