why Adds is error but add is correct?

In keil arm 2.11

while(1)
{
__asm
{
START: MOV R0,#0 MOV R1,#10
LOOP: BL ADD_SUB B LOOP
ADD_SUB:
ADD r0,r0,r1
//ADDS r0,r0,r1 <---error??
MOV PC,LR
}
}


FIBO.C(76): error C197: inline-asm: undefined identifier