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I’ve heard many things about performance in C; casting is slow compared to normal assignments, functional call is slow, binary operation are much faster than normal operations, et cetera…
I’m sure some of those things are specific to the architecture, and compiler optimization might make a huge difference, but I would like to see a chart to get a general idea what I should do and what I should avoid to write high-performance programs. Is there such a chart (or a website, a book, anything) ?
Basically, no. There is no such “tips and tricks” book from the syntax level, because there is no sure-fire guarantee that anything you stated is true (in fact, most of it is false).
In general, performance tuning should focus more on algorithms, followed by memory locality and cache optimizations. The best tools you will have are profilers (oprofile, valgrind, cachegrind, etc) followed by an understanding of machine architecture (instructions combinations which are suboptimal, alignment restrictions, memory hierarchy and size) and assembly language for your CPU (to catch less than optimal inner loop problems).
If you are interested in micro-optimizations on the Intel architecture (and all Intel compatible CPUs), this is a must read (PDF). There are more interesting guides on Agner’s website.