Segmentation Fault in x86 binarySearch implementation

Question

Given a binarySearch test that passes 4 arguments to my .s file:

1. a pointer to an int array
2. an int representing the beginning of the array
3. an int representing the end of the array
4. the target element

I'm trying to code a binarySearch method in x86-64, but am running into a segmentation fault, for what I assume has to do with trying to access memory that is random or something similar, but I have no idea what specifically is causing it. Are there any online compilers that allow me to compile a .cpp file with a .s file? That would help me to debug this.

But anyway, a look at the code is:

    global binarySearch

    section .text



binarySearch:

    push rsi
    push rbx    ; beginning of the array
    push rdx    ; end of the array
    push rcx    ; target
    push rdi

    ; mov rdx, rbx
    dec rdx
    ; mov rbx, 0

startBinarySearch:
    xor rax, rax
    cmp rbx, rdx
    jg notFound
    mov rax, rbx
    add rax, rdx
    shr rax, 1

    mov rdi, rsi
    add rdi, rax
    add rdi, rax
    cmp rcx, [rdi]

    je found
    jg largePivot
    jmp smallPivot

largePivot:
    inc rax
    mov rbx, rax
    jmp startBinarySearch

smallPivot:
    dec rax
    mov rdx, rax
    jmp startBinarySearch

notFound:
    mov rax, -1
    jmp end

found:
    jmp end

end:
    pop rdi
    pop rcx
    pop rdx
    pop rbx
    pop rsi
ret

which is paraphrased from a .asm version I have written, but the translation apparently didn't rollover correctly.

Are there any glaringly obvious reasons as to what's causing this segmentation fault? I've seen in a couple places that it could have to do with xor'ing the variables after I push them, but that previously hasn't worked.