cmd/compile: refactor Linksym

Extract a helper function, linksymname.
This simplifies Linksym,
and linksymname will be useful in future work.

Change-Id: Ic5ff8b704a16d5020f6931e008e2f630f687cbd3
Reviewed-on: https://go-review.googlesource.com/40550
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

diff --git a/src/cmd/compile/internal/gc/obj.go b/src/cmd/compile/internal/gc/obj.go
index ef5ce3191e53bc9543d0f2561aec9116dd64b6a2..8062a43126352260156d163dff1ee2f628ab6918 100644 (file)
--- a/src/cmd/compile/internal/gc/obj.go
+++ b/src/cmd/compile/internal/gc/obj.go
@@ -227,25 +227,24 @@ func dumpglobls() {
        funcsyms = nil
 }
 
+func linksymname(s *types.Sym) string {
+       if isblanksym(s) {
+               return "_"
+       }
+       if s.Linkname != "" {
+               return s.Linkname
+       }
+       return s.Pkg.Prefix + "." + s.Name
+}
+
 func Linksym(s *types.Sym) *obj.LSym {
        if s == nil {
                return nil
        }
-       if s.Lsym != nil {
-               return s.Lsym
+       if s.Lsym == nil {
+               s.Lsym = Ctxt.Lookup(linksymname(s), 0)
        }
-       var name string
-       if isblanksym(s) {
-               name = "_"
-       } else if s.Linkname != "" {
-               name = s.Linkname
-       } else {
-               name = s.Pkg.Prefix + "." + s.Name
-       }
-
-       ls := Ctxt.Lookup(name, 0)
-       s.Lsym = ls
-       return ls
+       return s.Lsym
 }
 
 func duintxx(s *types.Sym, off int, v uint64, wid int) int {