clean up dumpstack

Reference: /n/atom/patch/applied2013/dumpstackclean
Date: Sun Dec 29 16:05:00 CET 2013
Signed-off-by: quanstro@quanstr.net

--- /sys/src/nix/k10/archk10.c	Sun Dec 29 16:04:46 2013
+++ /sys/src/nix/k10/archk10.c	Sun Dec 29 16:04:46 2013
@@ -162,11 +162,6 @@
 }
 
 void
-archfmtinstall(void)
-{
-}
-
-void
 microdelay(int µs)
 {
 	u64int r, t;
--- /sys/src/nix/k10/trap.c	Sun Dec 29 16:04:47 2013
+++ /sys/src/nix/k10/trap.c	Sun Dec 29 16:04:48 2013
@@ -359,8 +359,7 @@
 			if(m->machno != 0){
 				iprint("cpu%d: nmi pc %#p\n",
 					m->machno, ureg->ip);
-				for(;;)
-					hardhalt();
+				ndnr();
 			}
 		}
 		dumpregs(ureg);
@@ -470,7 +469,6 @@
 	char *s;
 	uintptr l, v, i, estack;
 	extern ulong etext;
-	int x;
 
 	if((s = getconf("*nodumpstack")) != nil && atoi(s) != 0){
 		iprint("dumpstack disabled\n");
@@ -478,9 +476,7 @@
 	}
 	iprint("dumpstack\n");
 
-	x = 0;
-	x += iprint("ktrace 9%s %#p %#p\n", strrchr(conffile, '/')+1, ureg->ip, ureg->sp);
-	i = 0;
+	iprint("ktrace 9%s %#p %#p\n", strrchr(conffile, '/')+1, ureg->ip, ureg->sp);
 	if(up != nil
 //	&& (uintptr)&l >= (uintptr)up->kstack
 	&& (uintptr)&l <= (uintptr)up->kstack+KSTACK)
@@ -494,18 +490,15 @@
 			iprint("&m %#p &l %#p\n", m, &l);
 		return;
 	}
-	x += iprint("estackx %#p\n", estack);
-
+	i = 0;
+	iprint("estackx %#p\n", estack);
 	for(l = (uintptr)&l; l < estack; l += sizeof(uintptr)){
 		v = *(uintptr*)l;
 		if((KTZERO < v && v < (uintptr)&etext)
 		|| ((uintptr)&l < v && v < estack) || estack-l < 256){
-			x += iprint("%#16.16p=%#16.16p ", l, v);
-			i++;
-		}
-		if(i == 2){
-			i = 0;
-			x += iprint("\n");
+			iprint("%#16.16p=%#16.16p ", l, v);
+			if(i++&1)
+				iprint("\n");
 		}
 	}
 	if(i)