10. (10 pts) Consider an ISA made up of only the following 12 similar-to-LEGV8 instructions. ADD...

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10. (10 pts) Consider an ISA made up of only the following 12 similar-to-LEGV8 instructions. ADD R1, R2, R3 SUB R1, R2, R3 AND R1, R2, R3 OR R1, R2, R3 ADDI R1, R2, #5 ORI R1, R2, #5 LDUR R1, [R2, #4] STUR R1, [R2, #4] MUL R1, R2, R3 CBZ R1, label CBNZ R2, label B label // add contents of R3 to R2 and put in R1 //sub contents of R3 to R2 and put in R1 // and contents of R3 to R2 and put in R1 // or contents of R3 to R2 and put in R1 // add contents of R2 and 5 and put in R1 // or the contents of R2 and 5 and put in R1 // load contents of memory addressed by R2 and put in R1 // store contents of R1 to memory addressed by R2 // multiply contents of R3 with R2 and put in R1 // if contents of R1 does not equal R2, goto label // if contents of R1 equals R2, goto label // goto label a) How many bits for opcode are needed in order to encode the above instructions? Rd b) If the ISA has only 7 general-purpose registers (R0 thru R6) and it uses 16 bits to represent each of the above instructions. It could have several encoding formats. How many bits are needed for each register? What is the largest immediate value that can appear in the instruction? How far can you branch (i.e., can jump how many instructions)? Why? c) If all registers are 16-bit, what is the approximate size of the data memory? Why? 10. (10 pts) Consider an ISA made up of only the following 12 similar-to-LEGV8 instructions. ADD R1, R2, R3 SUB R1, R2, R3 AND R1, R2, R3 OR R1, R2, R3 ADDI R1, R2, #5 ORI R1, R2, #5 LDUR R1, [R2, #4] STUR R1, [R2, #4] MUL R1, R2, R3 CBZ R1, label CBNZ R2, label B label // add contents of R3 to R2 and put in R1 //sub contents of R3 to R2 and put in R1 // and contents of R3 to R2 and put in R1 // or contents of R3 to R2 and put in R1 // add contents of R2 and 5 and put in R1 // or the contents of R2 and 5 and put in R1 // load contents of memory addressed by R2 and put in R1 // store contents of R1 to memory addressed by R2 // multiply contents of R3 with R2 and put in R1 // if contents of R1 does not equal R2, goto label // if contents of R1 equals R2, goto label // goto label a) How many bits for opcode are needed in order to encode the above instructions? Rd b) If the ISA has only 7 general-purpose registers (R0 thru R6) and it uses 16 bits to represent each of the above instructions. It could have several encoding formats. How many bits are needed for each register? What is the largest immediate value that can appear in the instruction? How far can you branch (i.e., can jump how many instructions)? Why? c) If all registers are 16-bit, what is the approximate size of the data memory? Why?