How to get the C-compiler to use RLC and ACC.x

Hello,

I would like to know if there's any way I can write C code that will use the assembly instructions RLC and ACC.x efficiently. I would like to some C code that will result in:

MOV A,byBuffer
MOV c,bInput
RLC A
MOV byBuffer,A

The closest I could get was this:

byBuffer=(byBuffer<<1)&bInput;

Which results in:

MOV A,byBuffer
ADD A,ACC
MOV R7,A
MOV C,bInput
CLR A
RLC A
ANL A,R7
MOV byBuffer,A

The same thing happens when I want to use a specific bit from a byte. I have never seen the C-compiler use the ACC.x instruction. It uses solutions like this:

MOV A,R6
MOV R0,AR5
INC R0
SJMP ?C0078
?C0077:
CLR C
RLC A
?C0078:
DJNZ R0,?C0077

Any ideas ????