asm { DIV_U64_BY_U64:: ENTER 0 XOR RDX,RDX MOV RCX,64 MOV RAX,SF_ARG1[RBP] MOV RBX,SF_ARG2[RBP] @@1: SHL1 RAX RCL1 RDX CMP RBX,RDX JA @@2 INC RAX SUB RDX,RBX @@2: LOOP @@1 LEAVE RET1 16 } _extern DIV_U64_BY_U64 I64 DivU64ByU64(I64 dividend,I64 divisor); "123456/10=%d\n",DivU64ByU64(123456,10);