Saw a blog post titled "How many registers does an x86-64 CPU have?" and my immediate thought was "it's impossible to know and a sin to ask".
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@bitchboss @dascandy @ryanc yup, you even get them for the extended GPRs in x64
@bitchboss @ryanc @gsuberland we even got low ones for di, si, bp and sp... which means you cannot mov ah, bpl...
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@nspace
Ooh, links?
@gsuberland @ryanc -
Saw a blog post titled "How many registers does an x86-64 CPU have?" and my immediate thought was "it's impossible to know and a sin to ask".
If you think the answer is 16, by the way, no it is not.
@ryanc Is that how many can be addressed by each instruction or how many exist in the hardware?
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@ryanc Is that how many can be addressed by each instruction or how many exist in the hardware?
@GerardThornley how many exist in the hardware
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@ryanc yeah uhhh off the top of my head
rax, rbx, rcx, rdx, r8-r15, rdi, rsi, rsp, rbp, rip and all the components thereof, and rflags
zmm0-zmm??? (can't remember how many we have now) plus the ymm/xmm components.
6 ye olde segment registers.
gdtr, ldtr, idtr, and another I forgot the name of.
maybe 5 control registers? they're numbered to 15 but most are reserved
8 debug registers
x87 FPU and MMX weirdness
hundreds of MSRs, hundreds more if you count CPUID leaves
plus internal regs
@gsuberland @ryanc
Also known as a "bakers 16" -
@GerardThornley how many exist in the hardware
@ryanc tbh, I wouldn't be able to guess either way, as I've rarely done low-level stuff on intel chips. But I'll be interested to know the answer. Good thread.
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Saw a blog post titled "How many registers does an x86-64 CPU have?" and my immediate thought was "it's impossible to know and a sin to ask".
If you think the answer is 16, by the way, no it is not.
@ryanc I heard there are five bonus registers that only get unlocked when you're using all the normal registers
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Saw a blog post titled "How many registers does an x86-64 CPU have?" and my immediate thought was "it's impossible to know and a sin to ask".
If you think the answer is 16, by the way, no it is not.
African or European Registers?
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