mips

问题 As you all might know that the MIPS instruction set supports clz (count leading zero) as follows: clz $t0,$t1 count leading zeros t0 = # of leading zeros in t1 I am writing a single cycle datapath in verilog and was just wondering what the ALU needs to support in order for me to do this... any ideas?? 回答1: Here's a possible approach (I'm ignoring the case of an input of 0, which is probably best treated as a special case): The number of leading zeros in a 32-bit number is either: the number

问题 I'm trying to create a simple assembly code that takes an input N and returns the Nth fibonacci number (eg if you input 2, it should output 1 and if you input 3 it should output 2). My code doesn't throw any errors, but after you input a number it returns something weird. If you input 1, it returns 2685009921. If you input 2, it returns 0.01. If you input 3, it returns 0.02. If you input 4, it'll output the text at the beginning asking for a positive integer, then type 3 (the correct answer).

问题 I'm trying to create a simple assembly code that takes an input N and returns the Nth fibonacci number (eg if you input 2, it should output 1 and if you input 3 it should output 2). My code doesn't throw any errors, but after you input a number it returns something weird. If you input 1, it returns 2685009921. If you input 2, it returns 0.01. If you input 3, it returns 0.02. If you input 4, it'll output the text at the beginning asking for a positive integer, then type 3 (the correct answer).

问题 Currently in $t0, there is an asciiz string however this string consists of only numeric characters, and I would like this to be stored as an integer so I can add a number to it. However the method I am trying does not seem to work. I load the users input into $a0, then move that address to $t0, and then chop off a character, then I try using andi to mask the first four bits, but this gives a memory address out of bounds error, any suggestions? EDIT: now the code only prints out the first

问题 In my method one, I have the number that I want to shift by stored inside $a0 (e.g. 5 bits), and I want to shift $t9 by 5 bits, but I'm running into a bit of trouble. Does anyone know why? MethodOne: sw $a0, ($t8) sll $t9, $t9, $t8 回答1: To shift left by a variable amount, use sllv : sllv $t9, $t9, $a0 sll only takes an immediate shift amount. There is no need for sw or $t8 . 来源： https://stackoverflow.com/questions/26051933/shifting-left-in-mips

问题 Im writing some MIPS code to take a string of ASCII digits and convert the string into an integer. The string is entered by the user and can be at most 10 digits in length. My code works fine and uses the obvious method of performing looped addition after multiplying the Least Significant number in the string by a power of ten determined by the index of the array, starting from the last digit entered (10^0) to the first digit entered (10^n, n=number of digits in the array). I was wondering if

问题 Im writing some MIPS code to take a string of ASCII digits and convert the string into an integer. The string is entered by the user and can be at most 10 digits in length. My code works fine and uses the obvious method of performing looped addition after multiplying the Least Significant number in the string by a power of ten determined by the index of the array, starting from the last digit entered (10^0) to the first digit entered (10^n, n=number of digits in the array). I was wondering if

问题 The reference says the pseudo code for la (load address) is translated to: Pseudo : la $1, Label lui $1, Label[31:16] ori $1,$1, label[15:0] but when I try to assemble the code in MARS I get the error: "Invalid language element: 16] and if I remove the [31:16] part I get "Label": operand is of incorrect type Any idea? 回答1: That means that the 16 most significant bits of label are set in $1. Then, 16 less significant bits are or'ed with the 16 most significant bits. Here you can find the

问题 li $s5, 2 add $a0, $s5, $0 li $v0, 4 syscall Why system out is (null) in spim ? 回答1: Looks like you are trying to print an int, but the system call code you are providing stands for "print string". As you have no label called 2 (hence no string starting at address of label 2 ), the console prints out (null) . Try this li $a0, 2 #integer to be printed li $v0, 1 #system call code 1: print_int syscall Now it should print 2 Check out this table for syscall op codes. 来源： https://stackoverflow.com

问题 Is there any way to run a MIPS binary on a Linux x86/x86-x64 machine? I got some applications for Enigma2 set-top-boxes (which is also based on Linux) that I want to run on a x86/x86-64 machine. These plugins are only available for MIPS processors. 回答1: The keyword is "emulator". The most famous emulator is qemu which can pretty much emulate any architectures out there, but there are also lots of MIPS emulators on Linux that you can find in the Linux-MIPS wiki: Open Virtual Platforms (OVP)