/* ARM assembly AARCH64 Raspberry PI 3B */
/*  program binarydigit.s   */

/*******************************************/
/* Constantes file                         */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM64.inc"


/*******************************************/
/* Initialized data                        */
/*******************************************/
.data
sMessAffBindeb:  .asciz "The decimal value  "
sMessAffBin:     .asciz " should produce an output of "
szRetourLigne:   .asciz "\n"

/*******************************************/
/* Uninitialized data                       */
/*******************************************/
.bss
sZoneConv:                   .skip 100
sZoneBin:                    .skip 100
/*******************************************/
/*  code section                           */
/*******************************************/
.text
.global main
main:                /* entry of program  */
    mov x5,5
    mov x0,x5
    ldr x1,qAdrsZoneConv
    bl conversion10S
    mov x0,x5
    ldr x1,qAdrsZoneBin
    bl conversion2      // binary conversion and display résult
    ldr x0,qAdrsZoneBin
    ldr x0,qAdrsMessAffBindeb
    bl affichageMess
    ldr x0,qAdrsZoneConv
    bl affichageMess
    ldr x0,qAdrsMessAffBin
    bl affichageMess
    ldr x0,qAdrsZoneBin
    bl affichageMess
    ldr x0,qAdrszRetourLigne
    bl affichageMess
    /* other number */
    mov x5,50
    mov x0,x5
    ldr x1,qAdrsZoneConv
    bl conversion10S
    mov x0,x5
    ldr x1,qAdrsZoneBin
    bl conversion2      // binary conversion and display résult
    ldr x0,qAdrsZoneBin
    ldr x0,qAdrsMessAffBindeb
    bl affichageMess
    ldr x0,qAdrsZoneConv
    bl affichageMess
    ldr x0,qAdrsMessAffBin
    bl affichageMess
    ldr x0,qAdrsZoneBin
    bl affichageMess
    ldr x0,qAdrszRetourLigne
    bl affichageMess
    /* other number */
    mov x5,-1
    mov x0,x5
    ldr x1,qAdrsZoneConv
    bl conversion10S
    mov x0,x5
    ldr x1,qAdrsZoneBin
    bl conversion2      // binary conversion and display résult
    ldr x0,qAdrsZoneBin
    ldr x0,qAdrsMessAffBindeb
    bl affichageMess
    ldr x0,qAdrsZoneConv
    bl affichageMess
    ldr x0,qAdrsMessAffBin
    bl affichageMess
    ldr x0,qAdrsZoneBin
    bl affichageMess
    ldr x0,qAdrszRetourLigne
    bl affichageMess
    /* other number */
    mov x5,1
    mov x0,x5
    ldr x1,qAdrsZoneConv
    bl conversion10S
    mov x0,x5
    ldr x1,qAdrsZoneBin
    bl conversion2      // binary conversion and display résult
    ldr x0,qAdrsZoneBin
    ldr x0,qAdrsMessAffBindeb
    bl affichageMess
    ldr x0,qAdrsZoneConv
    bl affichageMess
    ldr x0,qAdrsMessAffBin
    bl affichageMess
    ldr x0,qAdrsZoneBin
    bl affichageMess
    ldr x0,qAdrszRetourLigne
    bl affichageMess


100:                            // standard end of the program */
    mov x0, #0                  // return code
    mov x8, #EXIT               // request to exit program
    svc 0                       // perform the system call
qAdrsZoneConv:         .quad sZoneConv
qAdrsZoneBin:           .quad sZoneBin
qAdrsMessAffBin:       .quad sMessAffBin
qAdrsMessAffBindeb:    .quad sMessAffBindeb
qAdrszRetourLigne:     .quad szRetourLigne
/******************************************************************/
/*     register conversion in binary                              */
/******************************************************************/
/* x0 contains the register */
/* x1 contains the address of receipt area */
conversion2:
    stp x2,lr,[sp,-16]!        // save  registers
    stp x3,x4,[sp,-16]!        // save  registers
    clz x2,x0                  // number of left zeros bits
    mov x3,64
    sub x2,x3,x2               // number of significant bits
    strb wzr,[x1,x2]           // store 0 final
    sub x3,x2,1                // position counter of the written character
2:                             // loop
    tst x0,1                   // test first bit
    lsr x0,x0,#1               // shift right one bit
    bne 3f
    mov x4,#48                 // bit = 0 => character '0'
    b 4f
3:
    mov x4,#49                 //   bit = 1   => character '1'
4:
    strb w4,[x1,x3]            // character in reception area at position counter
    sub x3,x3,#1
    subs x2,x2,#1              //  0 bits ?
    bgt 2b                     // no!  loop

100:
    ldp x3,x4,[sp],16          // restaur  2 registres
    ldp x2,lr,[sp],16          // restaur  2 registres
    ret                        // retour adresse lr x30
/********************************************************/
/*        File Include fonctions                        */
/********************************************************/
/* for this file see task include a file in language AArch64 assembly */
.include "../includeARM64.inc"