Breakdown MOV instruction on Intel 64 compatibility mode

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I'm checking the assembly code for a MOV instruction on Intel 64 (long) compatibility sub-mode.

For a mov edx,408ACB77 the debugger (x32dbg for Windows) shows

BA 408ACB77

From Intel 64 SDM this MOV instruction in compatibility mode should use a one-byte opcode plus a 32bit immediate value (77CB8A40). In Intel SDM the opcode for MOV should be B8 +rd id. +rd means look at the lower three bit of one-byte opcode for the target dword register (i.e. 32 bit register).

From Table 3.1 the EDX register has index 0x2 then we get 0x8+0x2 = 0xA, hence the opcode byte is actually BA.

Is the above correct ? Thanks in advance.

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