Quick Makefile questions

Hi! I''ve got a generic makefile with a list of dependencies and a single inference rule to make .c files into .o files. Heres the makefile ("..." means that there is more there, but it''s not important to my question):

...
CC_ARM	=	gcc -marm -mthumb-interwork
CC_THUMB =	gcc -mthumb -mthumb-interwork

CFILES_ARM	=	Irq.c		\

CFILES_THUMB	=	Debug.c		\
			Dma.c		\
			Input.c		\
			Level.c		\
			Main.c		\
			Math.c		\
			Render.c	\
			Sprite.c	\
			Timer.c	        \
			Video.c		\

OBJS	=	$(CFILES_ARM:.c=.o)			\
		$(CFILES_THUMB:.c=.o)			\

CFLAGS	=	-c -Wall
...

##############################################################
## RULES ##############################################################
...

%.o : %.c
    @ECHO Compiling ARM file $<...
    @$(CC_THUMB) $(CFLAGS) $< -o $@

...

##############################################################
## DEPENDENCIES ##############################################################
include C:\Game\Code\Dependencies\Debug.dpn
include C:\Game\Code\Dependencies\Input.dpn
include C:\Game\Code\Dependencies\Main.dpn
include C:\Game\Code\Dependencies\Video.dpn
include C:\Game\Code\Dependencies\Timer.dpn
include C:\Game\Code\Dependencies\Dma.dpn
include C:\Game\Code\Dependencies\Level.dpn
include C:\Game\Code\Dependencies\Math.dpn
include C:\Game\Code\Dependencies\Sprite.dpn
include C:\Game\Code\Dependencies\Irq.dpn

The .dpn files contain the dependencies for the .o files. My question is this: is there a way to make 2 inference rules to have some of the .c files compiled using the CC_THUMB compiler and others to use the CC_ARM compiler? For example say I need to compile irq.c using CC_ARM, and everything else using CC_THUMB...how would I go about doing this in my makefile? This is a problem becuase all the object files need to be .o (ie, I can''t have an inference rule for .o_thumb files and one fore .o_arm files). Maybe there is a way to do an if statement in a makefile? By the way, i''m using a gnu compiler (gcc). Any help would be great. Thanks!