Register Indirection

The C expression evaluator does not recognize brackets ([]) to indicate a memory location pointed to by a register. Instead, you use the BY, WO, and DW operators to reference the corresponding byte, word, or doubleword values.

MASM Expression CodeView Equivalent

BYTE PTR [bx] BY bx
WORD PTR [bp] WO bp
DWORD PTR [bp] DW bp