Seperate MSP430 cio syscalls into individual function sections.

START_FUNC: New macro.
    END_FUNC: New macro.
    exit, isatty, getpid, sc2: Use the new macros.

libgloss/msp430/ciosyscalls.S

@@ -22,26 +22,58 @@
 	sc2 \a,\a
 .endm
 
-.macro	sc2,name,num
-	.weak	\name
-	.global	\name
-\name:
-        call_   #__errno                 
-        movx_   #ENOSYS, @R12                
-	MOV.W	#-1,R12
-	ret_
+.macro START_FUNC name1, name2=foo
+	.pushsection .text.\name1,"ax",@progbits
+	.p2align 1
+	.weak	\name1
+	.global	\name1
+\name1:
+  .ifnc \name2,foo
+	.weak	\name2
+	.global	\name2
+\name2:
+  .endif
 .endm
 
-	.weak	exit
-	.weak	_exit
-	.global	exit
-	.global	_exit
-exit:
-_exit:
+.macro END_FUNC name1, name2=foo
+	.type \name1 , @function
+	.size \name1 , . - \name1
+  .ifnc \name2,foo
+	.type \name2 , @function
+	.size \name2 , . - \name2
+  .endif
+	.popsection
+.endm
+
+
+START_FUNC exit, _exit
 	/* For some reason, the board fails to stop at a breakpoint
 	   placed on top of a software breakpoint instruction.  */
 /*	MOV.B	#0,R3		; this is a software breakpoint instruction */
 1:	br_	#1b
+END_FUNC exit, _exit
+	
+
+START_FUNC isatty,_isatty
+	MOV	#1,R12
+	ret_
+END_FUNC isatty,_isatty
+
+
+START_FUNC getpid
+	MOV	#42,R12
+	ret_
+END_FUNC getpid
+
+
+.macro	sc2,name,num
+	START_FUNC \name
+        call_   #__errno                 
+        movx_   #ENOSYS, @R12                
+	MOV.W	#-1,R12
+	ret_
+	END_FUNC \name
+.endm
 
 #define SC(n) sc2 n,SYS_##n
 
@@ -52,18 +84,3 @@ _exit:
 	SC (fstat)
 	SC (lseek)
 	SC (kill)
-
-	.weak	isatty
-	.global	isatty
-isatty:
-	.weak	_isatty
-	.global	_isatty
-_isatty:
-	MOV	#1,R12
-	ret_
-	
-	.weak	getpid
-	.global	getpid
-getpid:
-	MOV	#42,R12
-	ret_