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Is there ever reason to think the >> (signed) and >>> (unsigned) right bit-shift operators in Java would perform differently? I can't detect any difference on my machine.
This is purely an academic question; it's never going to be the bottleneck I'm sure. I know: it's best to write what you mean foremost; use >> for division by 2, for example.
I assume it comes down to which architectures have which operations implemented as an instruction.
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Difference between >> and >>> operator. Both >> and >>> are used to shift the bits towards the right. The difference is that the >> preserve the sign bit while the operator >>> does not preserve the sign bit. To preserve the sign bit, you need to add 0 in the MSB.
The >>> operator is the unsigned right bit-shift operator in Java. It effectively divides the operand by 2 to the power of the right operand, or just 2 here.
The >> operator is a signed right shift operator and >>> is an unsigned right shift operator. The left operands value is moved right by the number of bits specified by the right operand.
Bit-shifting is still faster, but for non-power-of-two mul/div by the time you do all your shifts and add the results it's slower again.
No. Your compiler will translate these to bytecode and the JVM will interpret the bytecode for your architecture. I think it is safe to assume that your architecture has an instruction set which includes both operations be done in few clock cycles.
Anyway, there is a difference in the behavior of these operators, so it isn't like you can just interchange them.
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