Question

Translate following C# code into MIPS assembly language

int recursive(int x) {
return (x >= 0xFF) ? (recursive(x - 3) + recursive(x - 2))

                : ((x >= 0xF) ? recursive(x - 1) + 1 : 1);

Answer 1

Given C# code as follows:

int recursive(int x) {

return (x >= 0xFF) ? (recursive(x - 3) + recursive(x - 2)): ((x >= 0xF) ? recursive(x - 1) + 1 : 1);

}

Converted MIPS assembly language code:

CODE                                                                                COMMENT

recursive:                                                                        //function started

addiu $sp,$sp,-40                                                                    //intializing stack pointer

sw $31,36($sp)                                                                    //save word from stack pointer at $31

sw $fp,32($sp)           //save word from stack pointer at file pointer    sw $16,28($sp)                                                               //save word from stack pointer at $16

move $fp,$sp                                                               //move content of stack pointer to file pointer

sw $4,40($fp)                                                            //store word at $4 from file pointer

lw $2,40($fp)                                                           //load word from $2 to file pointer

nop                                                                          //do nothing

slt $2,$2,255                                                          //set $2 if $2<0xF

bne $2,$0,$L2                                                     //branch to L2 if $2 not equal to $0

nop                                                                   //do nothing

lw $2,40($fp)                                                // load $2 with file pointer value

nop                                                               //do nothing

addiu $2,$2,-3                                              //x=x-3 implemented and result stored at $2

move $4,$2                                                 //move the content of $2 to $4

jal recursive                                               //call recurisve function as recurisve(x-3)

nop                                                          //do nothing

move $16,$2                                       //move the content of $2 to $16

lw $2,40($fp)                                       //load the content of file pointer to $2

nop                                                    //do nothing

addiu $2,$2,-2                                   //set x=x-2 store result at $2

move $4,$2                                      //move content of $2 to $4

jal recursive                                      //call recursive function recursive(x-2)

nop                                                     //do nothing

addu $2,$16,$2                              //Add content of $16 and $2 and store the result in $2

b $L6                                              //goto branch L6

nop                                               //do nothing

$L2:

lw $2,40($fp)                         //load the content of $2 with file pointer

nop                                       //do nothing

slt $2,$2,15                          //set $2 if $2<0xF

bne $2,$0,$L4                  //if $2 not equal to 0 then goto branch L4

nop                                   //do nothing

lw $2,40($fp)                        //load the content of $2 with file pointer

nop                                       //do nothing

addiu $2,$2,-1                   //set $2 as x-1

move $4,$2                       //move content of $2 to $4

jal recursive                        //call recursive function as recursive(x-1)

nop                                    //do nothing

addiu $2,$2,1                 //Add 1 to $2 content

b $L6                             //branch to L6

nop                              // do nothing

$L4:

li $2,1 # 0x1                  //set $2 as 1

$L6:

move $sp,$fp           //move file pointer content to stack pointer

lw $31,36($sp)       //load stack pointer to $31

lw $fp,32($sp)        //load file pointer with stack pointer

lw $16,28($sp)        //load $16 with stack pointer

addiu $sp,$sp,40       //Add 40 to stack pointer

j $31                         //jump with $31

nop                           //do nothing