The bitwise operators shall perform bitwise manipulations on the operands; that is, the operator shall
combine a bit in one operand with its corresponding bit in the other operand to calculate 1 bit for the result.
Below are the results for each possible combinations
1 Bitwise binary AND operator:
2. Bitwise binary OR operator:
3. Bitwise binary exclusive or operator
The operators logical and (&&) and logical or (||) are logical connectives. The result of the evaluation of a logical comparison shall be 1 (defined as true), 0 (defined as false), or, if the result is ambiguous, the unknown value (x). The precedence of && is greater than that of ||, and both are lower than relational and equality operators.
A third logical operator is the unary logical negation operator (!). The negation operator converts a nonzero or true operand into 0 and a zero or false operand into 1. An ambiguous truth value remains as x.
Example 1—If reg alpha holds the integer value 237 and beta holds the value zero, then the following
examples perform as described:
regA = alpha && beta; // regA is set to 0
regB = alpha || beta; // regB is set to 1
All four equality operators shall have the same precedence.
For the logical equality and logical inequality operators (== and !=), if, due to unknown or high-impedance bits in the operands, the relation is ambiguous, then the result shall be a 1-bit unknown value (x).
For the case equality and case inequality operators (=== and !==), the comparison shall be done just as it is in the procedural case statement (see 9.5). Bits that are x or z shall be included in the comparison and shall match for the result to be considered equal. The result of these operators shall always be a known value, either 1 or 0.
Relational operators are used for comparing values. They return a Boolean result indicating the relationship between the operands.
Definitions of rational operator shown in below table-
An expression using these relational operators shall yield the scalar value 0 if the specified relation is false or the value 1 if it is true. If either operand of a relational operator contains an unknown (x) or highimpedance (z) value, then the result shall be a 1-bit unknown value (x).
When one or both operands of a relational expression are unsigned, the expression shall be interpreted as a comparison between unsigned values. If the operands are of unequal bit lengths, the smaller operand shall be zero-extended to the size of the larger operand.
When both operands are signed, the expression shall be interpreted as a comparison between signed values. If the operands are of unequal bit lengths, the smaller operand shall be sign-extended to the size of the larger operand.
If either operand is a real operand, then the other operand shall be converted to an equivalent real value and the expression shall be interpreted as a comparison between real values.