assembly - Instruction ANDN in MASM throws EXCEPTION_ILLEGAL_INSTRUCTION -


i learning x86-64 assembly. now, trying use andn (and not) instruction in masm 64-bit (ml64.exe) see in debugger how works.

my code is:

extrn exitprocess : proc .data .code     main proc         mov ebx, 01h         mov ecx, 01h         andn eax, ebx, ecx ;exception_illegal_instruction here :(          xor rcx, rcx         call exitprocess     main endp end

i using debugger x64dbg. on andn instruction throws exception_illegal_instruction.

how use instruction correctly?

my build.bat file:

@echo off ml64.exe prog1.asm /link /entry:main /subsystem:windows /defaultlib:"kernel32.lib" pause

regards, david


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