RO Finding Position of Most Significant Bit The positions of bits in a 32-bit register are...

 

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RO Finding Position of Most Significant Bit The positions of bits in a 32-bit register are counted from the least significant (rightmost) bit. Thus the first bit is 0, the next is 1, and the last is 31. A bit positions are: 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00 Complete the following ARM assembly routine, bit_pos that returns the position of the most significant bit that is 1. The can be done by expressing the value as a binary number, and counting from the right starting at 0, until the most significant bit is found. Some examples are: . 100100 first bit is at position 5 . 11 first bit is at position 1 • 1 first bit is at position 0 . O first bit is at position-1, no 1 in the value . 111100100 first bit is at position 8 Exercise 4 [5.0] Editor .arch armv4 syntax unified .text bit_pos: align 2 type -global bit pos mov pc, 1r. test, function Test Bench Simulation Output LOCK Run RO Finding Position of Most Significant Bit The positions of bits in a 32-bit register are counted from the least significant (rightmost) bit. Thus the first bit is 0, the next is 1, and the last is 31. A bit positions are: 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00 Complete the following ARM assembly routine, bit_pos that returns the position of the most significant bit that is 1. The can be done by expressing the value as a binary number, and counting from the right starting at 0, until the most significant bit is found. Some examples are: . 100100 first bit is at position 5 . 11 first bit is at position 1 • 1 first bit is at position 0 . O first bit is at position-1, no 1 in the value . 111100100 first bit is at position 8 Exercise 4 [5.0] Editor .arch armv4 syntax unified .text bit_pos: align 2 type -global bit pos mov pc, 1r. test, function Test Bench Simulation Output LOCK Run

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Heres the complete ARM assembly routine for finding the position of the most significant bit that is 1 Explanation The bitpos routine takes a single input value in r0 and returns the position of the m... View the full answer