News: 0000838488

  ARM Give a man a fire and he's warm for a day, but set fire to him and he's warm for the rest of his life (Terry Pratchett, Jingo)

[$] Challenges in protecting virtual machines from untrusted entities

([Security] Dec 1, 2020 20:01 UTC (Tue) (kashyap))


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#define BITCOUNT(x) (((BX_(x)+(BX_(x)>>4)) & 0x0F0F0F0F) % 255)
#define BX_(x) ((x) - (((x)>>1)&0x77777777) \
- (((x)>>2)&0x33333333) \
- (((x)>>3)&0x11111111))

-- really weird C code to count the number of bits in a word