July 2002
Intermediate to advanced
320 pages
8h 15m
English
Content preview from Hacker's Delight
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7-1. Reversing Bits and Bytes
By “reversing bits” we mean to reflect the contents of a register about the middle so that, for example,
By “reversing bytes” we mean a similar reflection of the four bytes of a register. Byte reversal is a necessary operation to convert data between the “little-endian” format used by DEC and Intel and the “big-endian” format used by most other manufacturers.
Bit reversal can be done quite efficiently by interchanging adjacent single bits, then interchanging adjacent 2-bit fields, and so on, as shown below [Aus1]. These five assignment statements can be executed in any order.
x = (x & 0x55555555) << 1 | (x & 0xAAAAAAAA) ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.