.intel_syntax noprefix
.extern main
.section .text

.global _start
_start:
    # On entry, the stack contains:
    # [rsp]     = argc (argument count)
    # [rsp+8]   = argv[0] (program name)
    # [rsp+16]  = argv[1] (first argument)
    # ...
    
    # Get argc from stack
    mov rdi, [rsp]          # rdi = argc
    
    # Calculate space needed for our array structure
    # We need: 8 bytes (length) + argc * 8 bytes (pointers)
    mov rax, rdi            # rax = argc
    shl rax, 3              # rax = argc * 8 (each pointer is 8 bytes)
    add rax, 8              # rax = 8 + argc * 8 (add space for length)
    
    # Allocate space on stack (align to 16 bytes)
    add rax, 15             # Round up to nearest 16
    and rax, -16            # Align to 16 bytes
    sub rsp, rax            # Allocate space
    
    # Store array length at beginning
    mov [rsp], rdi          # Store argc as array length
    
    # Copy argv pointers to our array
    lea rsi, [rsp + 8]      # rsi points to start of argv in stack
    lea rdi, [rsp + 8]      # rdi points to our array data (after length)
    mov rcx, [rsp]          # rcx = argc (loop counter)
    
copy_loop:
    test rcx, rcx           # Check if we're done
    jz done_copying
    
    mov rax, [rsi]          # Load argv[i] pointer
    mov [rdi], rax          # Store in our array
    add rsi, 8              # Move to next argv entry
    add rdi, 8              # Move to next array slot
    dec rcx                 # Decrement counter
    jmp copy_loop
    
done_copying:
    # Now rsp points to our array: [length][ptr0][ptr1]...[ptrN-1]
    mov rdi, rsp            # Pass array pointer to main
    call main
    
    # Clean up stack (restore original rsp)
    # Calculate how much we allocated
    mov rdi, [rsp]          # Get argc back
    shl rdi, 3              # argc * 8
    add rdi, 8              # + 8 for length
    add rdi, 15             # Round up
    and rdi, -16            # Align
    add rsp, rdi            # Restore stack
    
    # Exit with main's return value
    mov rdi, rax            # rax contains main's return value
    mov rax, 60             # sys_exit
    syscall