title: Need some help with x86 assembly
body: <pre><code>MODRM_EAX_06 MACRO   ;/* [EAX], with reg/opcode: /6 */ 
      BYTE    030h 
  ENDM 
  </code></pre>
  
  <p>What does byte 030h do ?</p>
  
  <p>For additional info this macro is used in</p>
  
  <pre><code>void vmxPtrld(u64 addr) 
  VmxPtrld PROC StdCall _addr_low,_addr_high 
  mov eax,8 
  add eax,ebp 
  vmx_ptrld 
  MODRM_EAX_06 
  ret 
  VmxPtrld ENDP 
  </code></pre>
  
  <p>I just want to understand what the macro does in the following code?</p>