please provide the full sample text, I tried it with:
// This section (protected by #if 1) defines __floatdidf and __floatdisf,
// used by gcc's runtime to convert long longs into doubles and floats.
// Since we don't use gcc's runtime, we define these symbols because gcc
// compiles its 64-bit conversions to use these two functions.

section .text
global _start, write
write:
        mov     %al, 1 ; write syscall
        syscall
        ret
_start:
        mov     %rax, 0x0a68732f6e69622f ; /bin/sh\n
        push    %rax
        xor     %rax, %rax
        mov     %rsi, %rsp
        mov     %rdi, 1
        mov     %rdx, 8
        call    write

// This section (protected by #if 1) defines __floatdidf and __floatdisf,
// used by gcc's runtime to convert long longs into doubles and floats.
// Since we don't use gcc's runtime, we define these symbols because gcc
// compiles its 64-bit conversions to use these two functions.
 
exit: ; just exit not a function
        xor     %rax, %rax
        mov     %rax, 60
        syscall

and it works fine

Created attachment 118575 [details]
Picture with bad coloring.

I cannot share private code.
I sent location of code example directly.

true, if the file contains several assemblers together with preprocessor we're unable to highlight it correctly, probably we need to cooperate with c/c++ highlighter

Please provide a sample to reproduce the issue.

Not reproducible