Reverse Engineering for Beginners

CHAPTER 17. FLOATING-POINT UNIT CHAPTER 17. FLOATING-POINT UNIT

TESTis executed:

Figure 17.9:OllyDbg:TESTis executed

ThePFflag is set to 1. Indeed: the number of bits set in 0 is 0 and 0 is an even number. OllyDbg disassemblesJPas
JPE^16 —they are synonyms. And it is about to trigger now.

(^16) Jump Parity Even (x86 instruction)