What do you mean? Without using defines? Defines are just a text pre-preprocessing thing. An example from optiboot.c:
__asm__ __volatile__ (
" com %[ch]\n" // ones complement, carry set
" sec\n"
"1: brcc 2f\n"
" cbi %[uartPort],%[uartBit]\n"
" rjmp 3f\n"
"2: sbi %[uartPort],%[uartBit]\n"
" nop\n"
"3: rcall uartDelay\n"
" rcall uartDelay\n"
" lsr %[ch]\n"
" dec %[bitcnt]\n"
" brne 1b\n"
:
:
[bitcnt] "d" (10),
[ch] "r" (ch),
[uartPort] "I" (_SFR_IO_ADDR(UART_PORT)),
[uartBit] "I" (UART_TX_BIT)
:
"r25"
);
No define there. No backslashes (apart from the \n inside the assembler string).