>type optest.dpr

program optest;

{$APPTYPE CONSOLE}

uses
  SysUtils;

type
  TMyType = packed record a, b, c, d: Byte; end;

var
  a, b, c: Cardinal;
  d: Word;

function InitializeMyType(const Input: Cardinal): TMyType; inline;
begin
  result.a := Input;
  result.b := Input shr 8;
  result.c := Input shr 16;
  result.d := Input shr 24;
end;

begin
  a := 0;
  b := 0;
  c := 0;
  d := 0;
  d := a;

  InitializeMyType($AABBCCDD);
end.

>c:objdump -d optest.o

optest.o:     file format elf32-littlearm


Disassembly of section .text.n_p$optest_initializemytype$longword$$tmytype:

00000000 <P$OPTEST_INITIALIZEMYTYPE$LONGWORD$$TMYTYPE>:
   0:   e24dd008        sub     sp, sp, #8
   4:   e20010ff        and     r1, r0, #255    ; 0xff
   8:   e5cd1000        strb    r1, [sp]
   c:   e1a01420        lsr     r1, r0, #8
  10:   e20110ff        and     r1, r1, #255    ; 0xff
  14:   e5cd1001        strb    r1, [sp, #1]
  18:   e1a01820        lsr     r1, r0, #16
  1c:   e20110ff        and     r1, r1, #255    ; 0xff
  20:   e5cd1002        strb    r1, [sp, #2]
  24:   e1a00c20        lsr     r0, r0, #24
  28:   e20000ff        and     r0, r0, #255    ; 0xff
  2c:   e5cd0003        strb    r0, [sp, #3]
  30:   e59d0000        ldr     r0, [sp]
  34:   e28dd008        add     sp, sp, #8
  38:   e1a0f00e        mov     pc, lr

Disassembly of section .text.n_main:

00000000 <PASCALMAIN>:
   0:   e92d4000        push    {lr}
   4:   e24dd004        sub     sp, sp, #4
   8:   ebfffffe        bl      0 <FPC_INITIALIZEUNITS>
   c:   e3a00000        mov     r0, #0
  10:   e3a00000        mov     r0, #0
  14:   e3a00000        mov     r0, #0
  18:   e3a00000        mov     r0, #0
  1c:   e3a01000        mov     r1, #0
  20:   e3a00000        mov     r0, #0
  24:   e3a00000        mov     r0, #0
  28:   e3a00000        mov     r0, #0
  2c:   e1a00801        lsl     r0, r1, #16
  30:   e1a00820        lsr     r0, r0, #16
  34:   e59f3070        ldr     r3, [pc, #112]  ; ac <PASCALMAIN+0xac>
  38:   e20300ff        and     r0, r3, #255    ; 0xff
  3c:   e20010ff        and     r1, r0, #255    ; 0xff
  40:   e3e000ff        mvn     r0, #255        ; 0xff
  44:   e0022000        and     r2, r2, r0
  48:   e1822001        orr     r2, r2, r1
  4c:   e1a00423        lsr     r0, r3, #8
  50:   e20000ff        and     r0, r0, #255    ; 0xff
  54:   e1a00400        lsl     r0, r0, #8
  58:   e2000cff        and     r0, r0, #65280  ; 0xff00
  5c:   e3e01cff        mvn     r1, #65280      ; 0xff00
  60:   e0022001        and     r2, r2, r1
  64:   e1822000        orr     r2, r2, r0
  68:   e1a00823        lsr     r0, r3, #16
  6c:   e20000ff        and     r0, r0, #255    ; 0xff
  70:   e1a00800        lsl     r0, r0, #16
  74:   e20008ff        and     r0, r0, #16711680       ; 0xff0000
  78:   e3e018ff        mvn     r1, #16711680   ; 0xff0000
  7c:   e0022001        and     r2, r2, r1
  80:   e1822000        orr     r2, r2, r0
  84:   e1a00c23        lsr     r0, r3, #24
  88:   e20000ff        and     r0, r0, #255    ; 0xff
  8c:   e1a00c00        lsl     r0, r0, #24
  90:   e20004ff        and     r0, r0, #-16777216      ; 0xff000000
  94:   e3e014ff        mvn     r1, #-16777216  ; 0xff000000
  98:   e0022001        and     r2, r2, r1
  9c:   e1822000        orr     r2, r2, r0
  a0:   ebfffffe        bl      0 <FPC_DO_EXIT>
  a4:   e28dd004        add     sp, sp, #4
  a8:   e8bd8000        pop     {pc}
  ac:   aabbccdd        .word   0xaabbccdd