[dev.cc] cmd/5g etc: code cleanup: delay var decls and eliminate dead code

Ran rsc.io/grind rev 6f0e601 on the source files.

The cleanups move var declarations as close to the use
as possible, splitting disjoint uses of the var into separate
variables. They also remove dead code (especially in
func sudoaddable), which helps with the var moving.

There's more cleanup to come, but this alone cuts the
time spent compiling html/template on my 2013 MacBook Pro
from 3.1 seconds to 2.3 seconds.

Change-Id: I4de499f47b1dd47a560c310bbcde6b08d425cfd6
Reviewed-on: https://go-review.googlesource.com/5637
Reviewed-by: Rob Pike <r@golang.org>

1 files changed, 4 insertions, 8 deletions

diff --git a/src/cmd/internal/obj/pass.go b/src/cmd/internal/obj/pass.go
index 812e00b557..b03cd431a9 100644
--- a/src/cmd/internal/obj/pass.go
+++ b/src/cmd/internal/obj/pass.go
@@ -33,9 +33,7 @@ package obj
 // Code and data passes.
 
 func Brchain(ctxt *Link, p *Prog) *Prog {
-	var i int
-
-	for i = 0; i < 20; i++ {
+	for i := 0; i < 20; i++ {
 		if p == nil || p.As != AJMP || p.Pcond == nil {
 			return p
 		}
@@ -46,10 +44,9 @@ func Brchain(ctxt *Link, p *Prog) *Prog {
 }
 
 func brloop(ctxt *Link, p *Prog) *Prog {
-	var c int
 	var q *Prog
 
-	c = 0
+	c := 0
 	for q = p; q != nil; q = q.Pcond {
 		if q.As != AJMP || q.Pcond == nil {
 			break
@@ -152,12 +149,11 @@ func checkaddr(ctxt *Link, p *Prog, a *Addr) {
 func linkpatch(ctxt *Link, sym *LSym) {
 	var c int32
 	var name string
-	var p *Prog
 	var q *Prog
 
 	ctxt.Cursym = sym
 
-	for p = sym.Text; p != nil; p = p.Link {
+	for p := sym.Text; p != nil; p = p.Link {
 		checkaddr(ctxt, p, &p.From)
 		checkaddr(ctxt, p, &p.From3)
 		checkaddr(ctxt, p, &p.To)
@@ -203,7 +199,7 @@ func linkpatch(ctxt *Link, sym *LSym) {
 		p.Pcond = q
 	}
 
-	for p = sym.Text; p != nil; p = p.Link {
+	for p := sym.Text; p != nil; p = p.Link {
 		p.Mark = 0 /* initialization for follow */
 		if p.Pcond != nil {
 			p.Pcond = brloop(ctxt, p.Pcond)