Bit-Operators¶
Bit Manipulation¶
C is a hardware language
⟶ many operators to manipulate individual bits
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bitwise AND |
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bitwise OR |
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bitwise XOR |
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shift left |
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shift right |
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bitwise invert |
Why?*
Manipulating hardware registers
Saving space (e.g. persistence, protocols)
…
Bitwise AND and OR¶
Extract/mask bits
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Gives |
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Add bits
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Gives |
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Bitwise XOR¶
Exclusive OR
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Gives |
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Shift Left¶
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Filled with zeroes from right
Bits fall off to the left
Shift Right¶
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Bits fall off to the right
unsigned: filled with zeroes from leftsigned: machine dependent
⟶ Shift operations on signed entities is nonsense anyway
Inverting (“One’s-Complement”)¶
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