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cmovqtoday at 6:06 PM2 repliesview on HN

> For memory operands, there's an additional twist: the bit index is a signed offset that can address bits outside the nominal operand. A bit index of 35 on a dword accesses bit 3 of the next dword in memory.

I wonder what is the use case for testing a bit outside of the memory address given.


Replies

rep_lodsbtoday at 6:20 PM

So you can have bit arrays of any length in memory, rather than just 32 bits in a register.

show 1 reply
juancntoday at 6:15 PM

It was probably easier to just implement it that way, given that the barrel shifter is 64 bits wide.