diff options
Diffstat (limited to 'src/cmd/internal/gc/swt.go')
| -rw-r--r-- | src/cmd/internal/gc/swt.go | 212 |
1 files changed, 80 insertions, 132 deletions
diff --git a/src/cmd/internal/gc/swt.go b/src/cmd/internal/gc/swt.go index 7c25041b46..81eb56c3a6 100644 --- a/src/cmd/internal/gc/swt.go +++ b/src/cmd/internal/gc/swt.go @@ -35,9 +35,7 @@ type Case struct { var C *Case func dumpcase(c0 *Case) { - var c *Case - - for c = c0; c != nil; c = c.link { + for c := c0; c != nil; c = c.link { switch c.type_ { case Tdefault: fmt.Printf("case-default\n") @@ -104,11 +102,6 @@ func ordlcmp(c1 *Case, c2 *Case) int { } func exprcmp(c1 *Case, c2 *Case) int { - var ct int - var n int - var n1 *Node - var n2 *Node - // sort non-constants last if c1.type_ != Texprconst { return +1 @@ -117,11 +110,11 @@ func exprcmp(c1 *Case, c2 *Case) int { return -1 } - n1 = c1.node.Left - n2 = c2.node.Left + n1 := c1.node.Left + n2 := c2.node.Left // sort by type (for switches on interface) - ct = int(n1.Val.Ctype) + ct := int(n1.Val.Ctype) if ct != int(n2.Val.Ctype) { return ct - int(n2.Val.Ctype) @@ -135,7 +128,7 @@ func exprcmp(c1 *Case, c2 *Case) int { } // sort by constant value - n = 0 + n := 0 switch ct { case CTFLT: @@ -181,16 +174,12 @@ func typecmp(c1 *Case, c2 *Case) int { } func csort(l *Case, f func(*Case, *Case) int) *Case { - var l1 *Case - var l2 *Case - var le *Case - if l == nil || l.link == nil { return l } - l1 = l - l2 = l + l1 := l + l2 := l for { l2 = l2.link if l2 == nil { @@ -217,7 +206,7 @@ func csort(l *Case, f func(*Case, *Case) int) *Case { l2 = l2.link } - le = l + le := l for { if l1 == nil { @@ -270,31 +259,24 @@ func newlabel_swt() *Node { * deal with fallthrough, break, unreachable statements */ func casebody(sw *Node, typeswvar *Node) { - var n *Node - var c *Node - var last *Node - var def *Node - var cas *NodeList - var stat *NodeList - var l *NodeList - var lc *NodeList - var go_ *Node - var br *Node - var lno int32 - var needvar bool - if sw.List == nil { return } - lno = setlineno(sw) + lno := setlineno(sw) - cas = nil // cases - stat = nil // statements - def = nil // defaults - br = Nod(OBREAK, nil, nil) + cas := (*NodeList)(nil) // cases + stat := (*NodeList)(nil) // statements + def := (*Node)(nil) // defaults + br := Nod(OBREAK, nil, nil) - for l = sw.List; l != nil; l = l.Next { + var c *Node + var go_ *Node + var needvar bool + var lc *NodeList + var last *Node + var n *Node + for l := sw.List; l != nil; l = l.Next { n = l.N setlineno(n) if n.Op != OXCASE { @@ -333,9 +315,7 @@ func casebody(sw *Node, typeswvar *Node) { stat = list(stat, Nod(OLABEL, go_.Left, nil)) if typeswvar != nil && needvar && n.Nname != nil { - var l *NodeList - - l = list1(Nod(ODCL, n.Nname, nil)) + l := list1(Nod(ODCL, n.Nname, nil)) l = list(l, Nod(OAS, n.Nname, typeswvar)) typechecklist(l, Etop) stat = concat(stat, l) @@ -375,16 +355,12 @@ func casebody(sw *Node, typeswvar *Node) { func mkcaselist(sw *Node, arg int) *Case { var n *Node - var c *Case var c1 *Case - var c2 *Case - var l *NodeList - var ord int - c = nil - ord = 0 + c := (*Case)(nil) + ord := 0 - for l = sw.List; l != nil; l = l.Next { + for l := sw.List; l != nil; l = l.Next { n = l.N c1 = new(Case) c1.link = c @@ -444,7 +420,8 @@ func mkcaselist(sw *Node, arg int) *Case { switch arg { case Stype: c = csort(c, typecmp) - for c1 = c; c1 != nil; c1 = c1.link { + var c2 *Case + for c1 := c; c1 != nil; c1 = c1.link { for c2 = c1.link; c2 != nil && c2.hash == c1.hash; c2 = c2.link { if c1.type_ == Ttypenil || c1.type_ == Tdefault { break @@ -463,7 +440,7 @@ func mkcaselist(sw *Node, arg int) *Case { Strue, Sfalse: c = csort(c, exprcmp) - for c1 = c; c1.link != nil; c1 = c1.link { + for c1 := c; c1.link != nil; c1 = c1.link { if exprcmp(c1, c1.link) != 0 { continue } @@ -481,17 +458,12 @@ func mkcaselist(sw *Node, arg int) *Case { var exprname *Node func exprbsw(c0 *Case, ncase int, arg int) *Node { - var cas *NodeList - var a *Node - var n *Node - var c *Case - var i int - var half int - var lno int - - cas = nil + cas := (*NodeList)(nil) if ncase < Ncase { - for i = 0; i < ncase; i++ { + var a *Node + var n *Node + var lno int + for i := 0; i < ncase; i++ { n = c0.node lno = int(setlineno(n)) @@ -520,13 +492,13 @@ func exprbsw(c0 *Case, ncase int, arg int) *Node { } // find the middle and recur - c = c0 + c := c0 - half = ncase >> 1 - for i = 1; i < half; i++ { + half := ncase >> 1 + for i := 1; i < half; i++ { c = c.link } - a = Nod(OIF, nil, nil) + a := Nod(OIF, nil, nil) a.Ntest = Nod(OLE, exprname, c.node.Left) typecheck(&a.Ntest, Erv) a.Nbody = list1(exprbsw(c0, half, arg)) @@ -539,19 +511,9 @@ func exprbsw(c0 *Case, ncase int, arg int) *Node { * rebuild case statements into if .. goto */ func exprswitch(sw *Node) { - var def *Node - var cas *NodeList - var a *Node - var c0 *Case - var c *Case - var c1 *Case - var t *Type - var arg int - var ncase int - casebody(sw, nil) - arg = Snorm + arg := Snorm if Isconst(sw.Ntest, CTBOOL) { arg = Strue if sw.Ntest.Val.U.Bval == 0 { @@ -560,7 +522,7 @@ func exprswitch(sw *Node) { } walkexpr(&sw.Ntest, &sw.Ninit) - t = sw.Type + t := sw.Type if t == nil { return } @@ -570,7 +532,7 @@ func exprswitch(sw *Node) { */ exprname = nil - cas = nil + cas := (*NodeList)(nil) if arg == Strue || arg == Sfalse { exprname = Nodbool(arg == Strue) } else if consttype(sw.Ntest) >= 0 { @@ -582,7 +544,8 @@ func exprswitch(sw *Node) { typechecklist(cas, Etop) } - c0 = mkcaselist(sw, arg) + c0 := mkcaselist(sw, arg) + var def *Node if c0 != nil && c0.type_ == Tdefault { def = c0.node.Right c0 = c0.link @@ -590,6 +553,10 @@ func exprswitch(sw *Node) { def = Nod(OBREAK, nil, nil) } + var c *Case + var a *Node + var ncase int + var c1 *Case loop: if c0 == nil { cas = list(cas, def) @@ -639,13 +606,8 @@ var facename *Node var boolname *Node func typeone(t *Node) *Node { - var init *NodeList - var a *Node - var b *Node - var var_ *Node - - var_ = t.Nname - init = nil + var_ := t.Nname + init := (*NodeList)(nil) if var_ == nil { typecheck(&nblank, Erv|Easgn) var_ = nblank @@ -653,9 +615,9 @@ func typeone(t *Node) *Node { init = list1(Nod(ODCL, var_, nil)) } - a = Nod(OAS2, nil, nil) + a := Nod(OAS2, nil, nil) a.List = list(list1(var_), boolname) // var,bool = - b = Nod(ODOTTYPE, facename, nil) + b := Nod(ODOTTYPE, facename, nil) b.Type = t.Left.Type // interface.(type) a.Rlist = list1(b) typecheck(&a, Etop) @@ -669,17 +631,12 @@ func typeone(t *Node) *Node { } func typebsw(c0 *Case, ncase int) *Node { - var cas *NodeList - var a *Node - var n *Node - var c *Case - var i int - var half int - - cas = nil + cas := (*NodeList)(nil) if ncase < Ncase { - for i = 0; i < ncase; i++ { + var n *Node + var a *Node + for i := 0; i < ncase; i++ { n = c0.node if c0.type_ != Ttypeconst { Fatal("typebsw") @@ -696,13 +653,13 @@ func typebsw(c0 *Case, ncase int) *Node { } // find the middle and recur - c = c0 + c := c0 - half = ncase >> 1 - for i = 1; i < half; i++ { + half := ncase >> 1 + for i := 1; i < half; i++ { c = c.link } - a = Nod(OIF, nil, nil) + a := Nod(OIF, nil, nil) a.Ntest = Nod(OLE, hashname, Nodintconst(int64(c.hash))) typecheck(&a.Ntest, Erv) a.Nbody = list1(typebsw(c0, half)) @@ -716,18 +673,6 @@ func typebsw(c0 *Case, ncase int) *Node { * into if statements */ func typeswitch(sw *Node) { - var def *Node - var cas *NodeList - var hash *NodeList - var a *Node - var n *Node - var c *Case - var c0 *Case - var c1 *Case - var ncase int - var t *Type - var v Val - if sw.Ntest == nil { return } @@ -743,7 +688,7 @@ func typeswitch(sw *Node) { return } - cas = nil + cas := (*NodeList)(nil) /* * predeclare temporary variables @@ -751,7 +696,7 @@ func typeswitch(sw *Node) { */ facename = temp(sw.Ntest.Right.Type) - a = Nod(OAS, facename, sw.Ntest.Right) + a := Nod(OAS, facename, sw.Ntest.Right) typecheck(&a, Etop) cas = list(cas, a) @@ -763,7 +708,7 @@ func typeswitch(sw *Node) { hashname = temp(Types[TUINT32]) typecheck(&hashname, Erv) - t = sw.Ntest.Right.Type + t := sw.Ntest.Right.Type if isnilinter(t) { a = syslook("efacethash", 1) } else { @@ -776,7 +721,8 @@ func typeswitch(sw *Node) { typecheck(&a, Etop) cas = list(cas, a) - c0 = mkcaselist(sw, Stype) + c0 := mkcaselist(sw, Stype) + var def *Node if c0 != nil && c0.type_ == Tdefault { def = c0.node.Right c0 = c0.link @@ -787,7 +733,9 @@ func typeswitch(sw *Node) { /* * insert if statement into each case block */ - for c = c0; c != nil; c = c.link { + var v Val + var n *Node + for c := c0; c != nil; c = c.link { n = c.node switch c.type_ { case Ttypenil: @@ -807,6 +755,10 @@ func typeswitch(sw *Node) { /* * generate list of if statements, binary search for constant sequences */ + var ncase int + var c1 *Case + var hash *NodeList + var c *Case for c0 != nil { if c0.type_ != Ttypeconst { n = c0.node @@ -895,22 +847,11 @@ func walkswitch(sw *Node) { */ func typecheckswitch(n *Node) { var top int - var lno int - var ptr int - var nilonly string var t *Type - var badtype *Type - var missing *Type - var have *Type - var l *NodeList - var ll *NodeList - var ncase *Node - var nvar *Node - var def *Node - lno = int(lineno) + lno := int(lineno) typechecklist(n.Ninit, Etop) - nilonly = "" + nilonly := "" if n.Ntest != nil && n.Ntest.Op == OTYPESW { // type switch @@ -933,6 +874,7 @@ func typecheckswitch(n *Node) { t = Types[TBOOL] } if t != nil { + var badtype *Type if okforeq[t.Etype] == 0 { Yyerror("cannot switch on %v", Nconv(n.Ntest, obj.FmtLong)) } else if t.Etype == TARRAY && !Isfixedarray(t) { @@ -951,8 +893,14 @@ func typecheckswitch(n *Node) { n.Type = t - def = nil - for l = n.List; l != nil; l = l.Next { + def := (*Node)(nil) + var ptr int + var have *Type + var nvar *Node + var ll *NodeList + var missing *Type + var ncase *Node + for l := n.List; l != nil; l = l.Next { ncase = l.N setlineno(n) if ncase.List == nil { |