cmd/compile: use printer in vconv

Change-Id: Ib30ed686448c4c0a5777cdf1d505ea06eb8b2a47
Reviewed-on: https://go-review.googlesource.com/27917
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

diff --git a/src/cmd/compile/internal/gc/fmt.go b/src/cmd/compile/internal/gc/fmt.go
index 423e2fc081763b4ebf80d0bb7ed6091743129af2..9352dbea7dbe75ff456b9d0c8381c9b43746620b 100644 (file)
--- a/src/cmd/compile/internal/gc/fmt.go
+++ b/src/cmd/compile/internal/gc/fmt.go
@@ -338,6 +338,8 @@ func jconv(n *Node, flag FmtFlag) string {
 
 // Fmt "%V": Values
 func vconv(v Val, flag FmtFlag) string {
+       var p printer
+
        switch u := v.U.(type) {
        case *Mpint:
                if !u.Rune {
@@ -347,17 +349,19 @@ func vconv(v Val, flag FmtFlag) string {
                        return bconv(u, 0)
                }
 
-               x := u.Int64()
-               if ' ' <= x && x < utf8.RuneSelf && x != '\\' && x != '\'' {
-                       return fmt.Sprintf("'%c'", int(x))
-               }
-               if 0 <= x && x < 1<<16 {
-                       return fmt.Sprintf("'\\u%04x'", uint(int(x)))
-               }
-               if 0 <= x && x <= utf8.MaxRune {
-                       return fmt.Sprintf("'\\U%08x'", uint64(x))
+               switch x := u.Int64(); {
+               case ' ' <= x && x < utf8.RuneSelf && x != '\\' && x != '\'':
+                       p.f("'%c'", int(x))
+
+               case 0 <= x && x < 1<<16:
+                       p.f("'\\u%04x'", uint(int(x)))
+
+               case 0 <= x && x <= utf8.MaxRune:
+                       p.f("'\\U%08x'", uint64(x))
+
+               default:
+                       p.f("('\\x00' + %v)", u)
                }
-               return fmt.Sprintf("('\\x00' + %v)", u)
 
        case *Mpflt:
                if flag&FmtSharp != 0 {
@@ -366,19 +370,22 @@ func vconv(v Val, flag FmtFlag) string {
                return fconv(u, FmtSharp)
 
        case *Mpcplx:
-               if flag&FmtSharp != 0 {
-                       return fmt.Sprintf("(%v+%vi)", &u.Real, &u.Imag)
-               }
-               if v.U.(*Mpcplx).Real.CmpFloat64(0) == 0 {
-                       return fmt.Sprintf("%vi", fconv(&u.Imag, FmtSharp))
-               }
-               if v.U.(*Mpcplx).Imag.CmpFloat64(0) == 0 {
+               switch {
+               case flag&FmtSharp != 0:
+                       p.f("(%v+%vi)", &u.Real, &u.Imag)
+
+               case v.U.(*Mpcplx).Real.CmpFloat64(0) == 0:
+                       p.f("%vi", fconv(&u.Imag, FmtSharp))
+
+               case v.U.(*Mpcplx).Imag.CmpFloat64(0) == 0:
                        return fconv(&u.Real, FmtSharp)
+
+               case v.U.(*Mpcplx).Imag.CmpFloat64(0) < 0:
+                       p.f("(%v%vi)", fconv(&u.Real, FmtSharp), fconv(&u.Imag, FmtSharp))
+
+               default:
+                       p.f("(%v+%vi)", fconv(&u.Real, FmtSharp), fconv(&u.Imag, FmtSharp))
                }
-               if v.U.(*Mpcplx).Imag.CmpFloat64(0) < 0 {
-                       return fmt.Sprintf("(%v%vi)", fconv(&u.Real, FmtSharp), fconv(&u.Imag, FmtSharp))
-               }
-               return fmt.Sprintf("(%v+%vi)", fconv(&u.Real, FmtSharp), fconv(&u.Imag, FmtSharp))
 
        case string:
                return strconv.Quote(u)
@@ -391,9 +398,12 @@ func vconv(v Val, flag FmtFlag) string {
 
        case *NilVal:
                return "nil"
+
+       default:
+               p.f("<ctype=%d>", v.Ctype())
        }
 
-       return fmt.Sprintf("<ctype=%d>", v.Ctype())
+       return p.String()
 }
 
 /*