mips libc updates for routerboard.  we are not in sync
with sources, except for the profiling changes, and turning
off profiling on getcallerpc().

Reference: /n/atom/patch/applied2013/libcrb
Date: Wed Jul 31 18:29:09 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/libc/mips/vlrt.c	Wed Jul 31 18:27:57 2013
+++ /sys/src/libc/mips/vlrt.c	Wed Jul 31 18:27:58 2013
@@ -30,6 +30,7 @@
 
 /* needed by profiler; can't be profiled. */
 #pragma profile off
+
 void
 _addv(Vlong *r, Vlong a, Vlong b)
 {
@@ -55,8 +56,6 @@
 	r->lo = lo;
 	r->hi = hi;
 }
-
-#pragma profile on
 
 void
 _d2v(Vlong *y, double d)
--- /sys/src/libc/mips/tas.s	Wed Jul 31 18:27:59 2013
+++ /sys/src/libc/mips/tas.s	Wed Jul 31 18:27:59 2013
@@ -1,5 +1,5 @@
 /*
- *	magnum user level lock code
+ *	mips user level lock code
  */
 
 #define	LL(base, rt)	WORD	$((060<<26)|((base)<<21)|((rt)<<16))
@@ -7,7 +7,7 @@
 #define	NOOP		WORD	$0x27
 #define COP3		WORD	$(023<<26)
 
-	TEXT	C_3ktas(SB), 1, $0
+	TEXT	C_3ktas(SB),$0
 	MOVW	R1, R21
 btas:
 	MOVW	R21, R1
@@ -17,7 +17,7 @@
 	BLTZ	R1, btas
 	RET
 
-	TEXT	C_4ktas(SB), 1, $0
+	TEXT	C_4ktas(SB), $0
 	MOVW	R1, R2		/* address of key */
 tas1:
 	MOVW	$1, R3
@@ -26,8 +26,4 @@
 	SC(2, 3)
 	NOOP
 	BEQ	R3, tas1
-	RET
-
-	TEXT	C_fcr0(SB), $0
-	MOVW	FCR0, R1
 	RET
--- /sys/src/libc/mips/mkfile	Wed Jul 31 18:28:00 2013
+++ /sys/src/libc/mips/mkfile	Wed Jul 31 18:28:00 2013
@@ -5,6 +5,7 @@
 SFILES=\
 	argv0.s\
 	atom.s\
+	c_fcr0.s\
 	getcallerpc.s\
 	getfcr.s\
 	main9.s\
--- /sys/src/libc/mips/c_fcr0.s	Thu Jan  1 00:00:00 1970
+++ /sys/src/libc/mips/c_fcr0.s	Wed Jul 31 18:28:01 2013
@@ -0,0 +1,3 @@
+	TEXT	C_fcr0(SB), $0
+	MOVW	FCR0, R1
+	RET
--- /sys/src/libc/mips/cycles.c	Wed Jul 31 18:28:02 2013
+++ /sys/src/libc/mips/cycles.c	Wed Jul 31 18:28:02 2013
@@ -1,7 +1,10 @@
 #include <u.h>
 #include <libc.h>
 
-void	cycles(uvlong*u)
+#pragma profile off
+
+void
+cycles(uvlong*u)
 {
 	*u = 0LL;
 }
--- /sys/src/libc/mips/atom.s	Wed Jul 31 18:28:03 2013
+++ /sys/src/libc/mips/atom.s	Wed Jul 31 18:28:03 2013
@@ -49,9 +49,3 @@
 fail:
 	MOVW	$0, R1
 	RET
-
-/* general-purpose abort */
-_trap:
-	MOVD	$0, R0
-	MOVD	0(R0), R0
-	RET
--- /sys/src/libc/mips/main9p.s	Wed Jul 31 18:28:04 2013
+++ /sys/src/libc/mips/main9p.s	Wed Jul 31 18:28:04 2013
@@ -3,6 +3,7 @@
 TEXT	_mainp(SB), 1, $(16 + NPRIVATES*4)
 
 	MOVW	$setR30(SB), R30
+	/* _tos = arg */
 	MOVW	R1, _tos(SB)
 
 	MOVW	$p-64(SP), R1
@@ -10,9 +11,13 @@
 	MOVW	$NPRIVATES, R1
 	MOVW	R1, _nprivates(SB)
 
+	/* _profmain(); */
 	JAL	_profmain(SB)
-	MOVW	__prof+4(SB), R1
-	MOVW	R1, __prof+0(SB)
+	/* _tos->prof.pp = _tos->prof.next; */
+	MOVW	_tos(SB), R1
+	MOVW	4(R1), R2
+	MOVW	R2, 0(R1)
+	/* main(argc, argv); */
 	MOVW	inargc-4(FP), R1
 	MOVW	$inargv+0(FP), R2
 	MOVW	R1, 4(R29)