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Pointer arithmetic, that is, the ability to modify a pointer's target address with arithmetic operations (as well as magnitude comparisons), is restricted by the language standard to remain within the bounds of a single array object (or just after it), and will otherwise invoke undefined behavior.
In languages with typed pointers like C, the increment operator steps the pointer to the next item of that type -- increasing the value of the pointer by the size of that type. When a pointer (of the right type) points to any item in an array, incrementing (or decrementing) makes the pointer point to the "next" (or "previous") item of that array.
The precedence of the bitwise logical operators has been criticized. [16] Conceptually, & and | are arithmetic operators like * and +. The expression a & b == 7 is syntactically parsed as a & (b == 7) whereas the expression a + b == 7 is parsed as (a + b) == 7. This requires parentheses to be used more often than they otherwise would.
Far pointers are 32-bit pointers containing a segment and an offset. To use them the segment register ES is used by using the instruction les [reg]|[mem],dword [mem]|[reg]. [1] They may reference up to 1024 KiB of memory. Note that pointer arithmetic (addition and subtraction) does not modify the segment portion of the pointer, only its offset.
Conversely, one may use either a leaky bucket approach or pointer arithmetic to generate flags in synchronous FIFO implementations. A hardware FIFO is used for synchronization purposes. It is often implemented as a circular queue, and thus has two pointers: Read pointer / read address register; Write pointer / write address register
The program counter (PC), [1] commonly called the instruction pointer (IP) in Intel x86 and Itanium microprocessors, and sometimes called the instruction address register (IAR), [2] [1] the instruction counter, [3] or just part of the instruction sequencer, [4] is a processor register that indicates where a computer is in its program sequence.
In contrast, in the pointer machine model, read and write operations use addresses stored in pointers, and it is not allowed to perform arithmetic operations on these pointers. In both models, data values may be added, and bitwise Boolean operations and binary shift operations may typically also be performed on them, in unit time per operation.
C provides a compound assignment operator for each binary arithmetic and bitwise operation. Each operator accepts a left operand and a right operand, performs the appropriate binary operation on both and stores the result in the left operand. [6] The bitwise assignment operators are as follows.