This differs from a macro to do this at assembly time, its a tool for runtime evaluation of words and if they are registers the size in bytes is returned in RAX.
This is the calling code but I have not published the macros yet as they are subject to serious testing.
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include \masm32\include64\masm64rt.inc
.code
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entry_point proc
.stackspace 8
print str$(rv(allregs,"r9b")),lf, \
str$(rv(allregs,"r11w")),lf, \
str$(rv(allregs,"eax")),lf, \
str$(rv(allregs,"rdx")),lf, \
str$(rv(allregs,"st(0)")),lf, \
str$(rv(allregs,"xmm7")),lf, \
str$(rv(allregs,"ymm3")),lf
waitkey
fn ExitProcess,0
ret
entry_point endp
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include allregs.asm
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end
The file allregs.asm is attached in a zip file.