cmd/compile: use range construct

so the code is more readable.

Also use n[i] = val instead of n = append(n, val),
because this avoids a function call to append.

NOTE: compiles, but I had trouble running toolstash -cmp and need sleep
now.

@Ian this might save you some grunt work :-)

Change-Id: I2a4c70396c58905f7d5aabf83f3020f11dea0e89
Reviewed-on: https://go-review.googlesource.com/20430Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/cmd/compile/internal/gc/bimport.go

@@ -347,9 +347,9 @@ func (p *importer) fieldList() []*Node {
 	if i == 0 {
 		return nil
 	}
-	n := make([]*Node, 0, i)
-	for ; i > 0; i-- {
-		n = append(n, p.field())
+	n := make([]*Node, i)
+	for i := range n {
+		n[i] = p.field()
 	}
 	return n
 }
@@ -394,9 +394,9 @@ func (p *importer) methodList() []*Node {
 	if i == 0 {
 		return nil
 	}
-	n := make([]*Node, 0, i)
-	for ; i > 0; i-- {
-		n = append(n, p.method())
+	n := make([]*Node, i)
+	for i := range n {
+		n[i] = p.method()
 	}
 	return n
 }
@@ -440,9 +440,9 @@ func (p *importer) paramList() []*Node {
 		named = false
 	}
 	// i > 0
-	n := make([]*Node, 0, i)
-	for ; i > 0; i-- {
-		n = append(n, p.param(named))
+	n := make([]*Node, i)
+	for i := range n {
+		n[i] = p.param(named)
 	}
 	return n
 }
@@ -551,9 +551,9 @@ func (p *importer) float(x *Mpflt) {
 // parser.go:stmt_list
 func (p *importer) nodeList() []*Node {
 	c := p.int()
-	s := make([]*Node, 0, c)
-	for i := 0; i < c; i++ {
-		s = append(s, p.node())
+	s := make([]*Node, c)
+	for i := range s {
+		s[i] = p.node()
 	}
 	return s
 }
@@ -817,7 +817,7 @@ func (p *importer) string() string {
 		} else {
 			p.buf = p.buf[:n]
 		}
-		for i := 0; i < n; i++ {
+		for i := range p.buf {
 			p.buf[i] = p.byte()
 		}
 		return string(p.buf)