cmd/compile: eliminate NumFields wrapper functions

Change-Id: I3c6035559288cfdc33857216f50241b81932c8a4
Reviewed-on: https://go-review.googlesource.com/20811
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go
index 1d3c1f6..84dc29c 100644
--- a/src/cmd/compile/internal/gc/ssa.go
+++ b/src/cmd/compile/internal/gc/ssa.go
@@ -2639,7 +2639,7 @@
 		// introduced by the compiler for variadic functions.
 		return false
 	case TSTRUCT:
-		if countfield(t) > ssa.MaxStruct {
+		if t.NumFields() > ssa.MaxStruct {
 			return false
 		}
 		for _, t1 := range t.Fields().Slice() {