Low & High Suspicious Operand Limits

If IDA suspects that an operand can be represented as something different from a plain number, it will mark the operand as "suspicious" and display it in red/orange.

Two values control the definition of suspiciousness. An operand is 'suspicious' if it has an immediate value between low and high 'suspicious' limits. The comparison is always unsigned, i.e. in the instruction

        mov ax,[bp-2]

  the immediate operand is 0xFFFE, not -2.

IDA uses a simple heuristic to determine initial suspiciousness limits. You may change these limits any time you want.