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Error in Table "32/64-bit ModR/M Byte" #17

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mazegen opened this issue Jun 5, 2024 · 0 comments
Open

Error in Table "32/64-bit ModR/M Byte" #17

mazegen opened this issue Jun 5, 2024 · 0 comments
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@mazegen
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mazegen commented Jun 5, 2024

In the Table "32/64-bit ModR/M Byte", for Mod=00, R/M=001 the effective address is listed as "[RCX/EDX]+disp8". This is incorrect, it should be "[RCX/ECX]+disp8". (I.e. with 32-bit operands the base register remains ECX.)

This is verified both by the correct listing in the table below, "32-bit ModR/M Byte", as well as Intel's official manual.

It's a typo. Relevant link: http://ref.x86asm.net/coder64.html#modrm_byte_32_64

Reported by d0sboots.

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