runtime: eliminate unnecessary type conversions

Automated refactoring produced using github.com/mdempsky/unconvert.

Change-Id: Iacf871a4f221ef17f48999a464ab2858b2bbaa90
Reviewed-on: https://go-review.googlesource.com/20071
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/runtime/stack.go b/src/runtime/stack.go
index f786514..b89dc59 100644
--- a/src/runtime/stack.go
+++ b/src/runtime/stack.go
@@ -563,7 +563,7 @@
 	minp := adjinfo.old.lo
 	maxp := adjinfo.old.hi
 	delta := adjinfo.delta
-	num := uintptr(bv.n)
+	num := bv.n
 	for i := uintptr(0); i < num; i++ {
 		if stackDebug >= 4 {
 			print("        ", add(scanp, i*sys.PtrSize), ":", ptrnames[ptrbit(&bv, i)], ":", hex(*(*uintptr)(add(scanp, i*sys.PtrSize))), " # ", i, " ", bv.bytedata[i/8], "\n")
@@ -665,7 +665,7 @@
 		} else {
 			stackmap := (*stackmap)(funcdata(f, _FUNCDATA_ArgsPointerMaps))
 			if stackmap == nil || stackmap.n <= 0 {
-				print("runtime: frame ", funcname(f), " untyped args ", frame.argp, "+", uintptr(frame.arglen), "\n")
+				print("runtime: frame ", funcname(f), " untyped args ", frame.argp, "+", frame.arglen, "\n")
 				throw("missing stackmap")
 			}
 			if pcdata < 0 || pcdata >= stackmap.n {