Arm comparison instructions most arithmeticlogic

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Unformatted text preview: - Fill bits with zeroes. - 0b1001 logical shift right by 2 - > 0b0010 - mov r0, r1, lsr r2 // r0 = r1 >> (r2 & 0xFF); // r1 declared as unsigned; - mov r0, r1, lsr #2 // r0 = r1 >> 2; // r1 declared as unsigned; - Arithmetic Shift Right - Constant shift value will be in the range 1- 32. - Fill bits with sign bits. - 0b1001 arithmetic shift right by 2 - > 0b1110 - mov r0, r1, asr r2 // r0 = r1 >> (r2 & 0xFF); // r1 declared as signed; - mov r0, r1, asr #2 // r0 = r1 >> 2; // r1 declared as signed; - Rotate Right - Constant shift value will be in the range 1- 31. - mov r0, r1, ror #4 // If r1 == 0xABCD EF01, // then r0 = 0x1ABC DEF0; 7. ARM Comparison Instructions - Most arithmetic/logic instructions with a S suffix and compare instructions can set PSR(Program Status Register). - Four flags can be set: - N set if the result is negative. - Z set if the result is zero. - C set if last addition/subtraction had a carry/borrow out of bit 31 - V set if last addition/subtracti...
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