作业1—lab1指令集结构—计算机体系结构.docx

Lab1 作业 学号 姓名：崔雪莹 Exercise 1: What will be 32-bit hex code for the above two examples. LW R2, 100(R3) 指令为读指令，读R3寄存器内容为首址，偏移地址为100的内容字，存到R2寄存器里，格式 LW rt, Imm(rs)。 编码为：100011 00011 00010 01100100 Bit313029282726252423222120191817161514131211109876543210Field6-Bit Op Coders Fieldrt Field16-bit Immediate field10001100011000100000000001100100 SW R5, 100(R6) 指令为写指令，将R5内容写入以R6寄存器内容为首址，偏移地址为100的地址，格式 SW rt, Imm(rs)。 编码为：101011 00110 00101 01100100 Bit313029282726252423222120191817161514131211109876543210Field6-Bit Op Coders Fieldrt Field16-bit Immediate field10101100110001010000000001100100 Exercise 2: Find 32-bit code for OR R7, R18, R12 and SUB R5, R4, R31 OR R7, R18, R12 位或操作，格式 OpCode rd, rs, rt 编码为：000000 10010 01100 00111 00000 100101 Bit313029282726252423222120191817161514131211109876543210Field0 0 0 0 0 0rs Fieldrt Fieldrd fieldShift AmountFunction Field00000010010011000011100000100101 SUB R5, R4, R31 减法，格式 OpCode rd, rs, rt 编码为：000000 00100 11111 00101 00000 100010 Bit313029282726252423222120191817161514131211109876543210Field0 0 0 0 0 0rs Fieldrt Fieldrd fieldShift AmountFunction Field00000000100111110010100000100010 Exercise 3: Find 32-bit code for BNEQ R7, R8, -5. 0000101 00111 01000 11111011 If the PC value for branch instruction is 124 what will be new value of PC if the branch is taken 124+4-5*4=108 . -5的补码为 1111 1111 1111 1011 Bit313029282726252423222120191817161514131211109876543210Field000100 for BEQ 000101 for BNEQrs Fieldrt FieldBranch offset in Number of Instructions00010100111010001111111111111011