push $1/pop %eax (6a 01 58) is shorter, but perhaps not the best idea. | Hacker News

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gsg on June 11, 2017 | parent | context | favorite | on: Intel fires warning shots at Microsoft, says x86 e...

push $1/pop %eax (6a 01 58) is shorter, but perhaps not the best idea.

nayuki on June 11, 2017 [–]

Actually, there is no 32-bit pop instruction in x86-64 mode. Your code won't work.

gsg on June 11, 2017 | [–]

You're right: it should be pushq $1/pop %rax (which is also three bytes, although there will be a prefix byte for registers r8 through r15).

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