Microsoft Word - iOSAppReverseEngineering.docx

Figure 6-4 LSL

LSR Logical Shift Right, as shown in figure 6 - 5

Figure 6-5 LSR

ASR Arithmetic Shift Right, as shown in figure 6- 6

Figure 6-6 ASR

ROR ROtate Right, as shown in figure 6- 7

Figure 6-7 ROR

-^ Compare instructions

CMP R1, R2 ; Set flag according to the result of R1 - R2

CMN R1, R2 ; Set flag according to the result of R1 + R2

TST R1, R2 ; Set flag according to the result of R1 & R2

TEQ R1, R2 ; Set flag according to the result of R1 ^ R2

Compare instructions are just arithmetic or logical operation instructions that change flags,

but they don’t save the results in registers.

• Multiply instructions

MUL R4, R3, R2 ; R4 = R3 * R2

MLA R4, R3, R2, R1 ; R4 = R3 * R2 + R1

The operands of multiply instructions must come from registers.