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GeoffTidey/shrd.rb

Created July 31, 2012 17:19
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A ruby interpretation of the shrd (Double Precision Shift Right) Assembly instruction
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shrd.rb
#see https://en.wikibooks.org/wiki/X86_Assembly/Shift_and_Rotate#Extended_Shift_Instructions for more info on shrd
def shrd(rm16, r16, cl)
rm16 >>= cl
r16 <<= (16 - cl)
rm16 | (r16 & 0xFFFF)
end
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More here: http://blog.tidey.net/blog/2012/07/31/shrd-a-ruby-interpretation-of-the-double-precision-shift-right-assembly-instruction/

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