cmd/{5,6,8,9}g, cmd/internal/gc: use bools for is* and okfor*

No functional changes.

This diff was generated as follows:

* Manually edit cmd/internal/gc/go.go to update types and group variables.
* Manually edit initialization in cmd/internal/gc/align.go--localized s/1/true.
* Manually fix the handling of sign in cmd/internal/gc/walk.go in func bounded (near line 4000).
* Manually update go.y and regenerate y.go.
* Run gofmt -r many times to do the rest, using https://gist.github.com/josharian/0f61dbb2dff81f938e70.

toolstash -cmp on the stdlib comes back green.

Change-Id: I19766ed551714e51b325133e7138818d117b3a9a
Reviewed-on: https://go-review.googlesource.com/6530
Reviewed-by: Russ Cox <rsc@golang.org>
diff --git a/src/cmd/5g/cgen.go b/src/cmd/5g/cgen.go
index d9d4892..fdfd185 100644
--- a/src/cmd/5g/cgen.go
+++ b/src/cmd/5g/cgen.go
@@ -107,7 +107,7 @@
 
 	// if both are addressable, move
 	if n.Addable != 0 && res.Addable != 0 {
-		if gc.Is64(n.Type) || gc.Is64(res.Type) || n.Op == gc.OREGISTER || res.Op == gc.OREGISTER || gc.Iscomplex[n.Type.Etype] != 0 || gc.Iscomplex[res.Type.Etype] != 0 {
+		if gc.Is64(n.Type) || gc.Is64(res.Type) || n.Op == gc.OREGISTER || res.Op == gc.OREGISTER || gc.Iscomplex[n.Type.Etype] || gc.Iscomplex[res.Type.Etype] {
 			gmove(n, res)
 		} else {
 			var n1 gc.Node
@@ -148,7 +148,7 @@
 	}
 
 	// if n is sudoaddable generate addr and move
-	if !gc.Is64(n.Type) && !gc.Is64(res.Type) && gc.Iscomplex[n.Type.Etype] == 0 && gc.Iscomplex[res.Type.Etype] == 0 {
+	if !gc.Is64(n.Type) && !gc.Is64(res.Type) && !gc.Iscomplex[n.Type.Etype] && !gc.Iscomplex[res.Type.Etype] {
 		a := optoas(gc.OAS, n.Type)
 		var w int
 		var addr obj.Addr
@@ -220,7 +220,7 @@
 	var f0 gc.Node
 	var n1 gc.Node
 	var n2 gc.Node
-	if nl != nil && gc.Isfloat[n.Type.Etype] != 0 && gc.Isfloat[nl.Type.Etype] != 0 {
+	if nl != nil && gc.Isfloat[n.Type.Etype] && gc.Isfloat[nl.Type.Etype] {
 		// floating-point.
 		regalloc(&f0, nl.Type, res)
 
@@ -338,7 +338,7 @@
 			regalloc(&n1, nl.Type, res)
 			gmove(nl, &n1)
 		} else {
-			if n.Type.Width > int64(gc.Widthptr) || gc.Is64(nl.Type) || gc.Isfloat[nl.Type.Etype] != 0 {
+			if n.Type.Width > int64(gc.Widthptr) || gc.Is64(nl.Type) || gc.Isfloat[nl.Type.Etype] {
 				gc.Tempname(&n1, nl.Type)
 			} else {
 				regalloc(&n1, nl.Type, res)
@@ -347,7 +347,7 @@
 		}
 
 		var n2 gc.Node
-		if n.Type.Width > int64(gc.Widthptr) || gc.Is64(n.Type) || gc.Isfloat[n.Type.Etype] != 0 {
+		if n.Type.Width > int64(gc.Widthptr) || gc.Is64(n.Type) || gc.Isfloat[n.Type.Etype] {
 			gc.Tempname(&n2, n.Type)
 		} else {
 			regalloc(&n2, n.Type, nil)
@@ -1269,7 +1269,7 @@
 		gc.OGE:
 		a := int(n.Op)
 		if !true_ {
-			if gc.Isfloat[nl.Type.Etype] != 0 {
+			if gc.Isfloat[nl.Type.Etype] {
 				// brcom is not valid on floats when NaN is involved.
 				p1 := gc.Gbranch(arm.AB, nil, 0)
 
@@ -1328,7 +1328,7 @@
 			break
 		}
 
-		if gc.Iscomplex[nl.Type.Etype] != 0 {
+		if gc.Iscomplex[nl.Type.Etype] {
 			gc.Complexbool(a, nl, nr, true_, likely, to)
 			break
 		}
@@ -1408,7 +1408,7 @@
 		gmove(&tmp, &n2)
 
 		gcmp(optoas(gc.OCMP, nr.Type), &n1, &n2)
-		if gc.Isfloat[nl.Type.Etype] != 0 {
+		if gc.Isfloat[nl.Type.Etype] {
 			if n.Op == gc.ONE {
 				p1 := gc.Gbranch(arm.ABVS, nr.Type, likely)
 				gc.Patch(gc.Gbranch(a, nr.Type, likely), to)
@@ -1441,7 +1441,7 @@
 
 	case gc.ODOT:
 		t := n.Left.Type
-		if gc.Isptr[t.Etype] != 0 {
+		if gc.Isptr[t.Etype] {
 			break
 		}
 		off := stkof(n.Left)
@@ -1468,7 +1468,7 @@
 		gc.OCALLINTER,
 		gc.OCALLFUNC:
 		t := n.Left.Type
-		if gc.Isptr[t.Etype] != 0 {
+		if gc.Isptr[t.Etype] {
 			t = t.Type
 		}
 
diff --git a/src/cmd/5g/ggen.go b/src/cmd/5g/ggen.go
index 2879805..aa0e6f4 100644
--- a/src/cmd/5g/ggen.go
+++ b/src/cmd/5g/ggen.go
@@ -383,7 +383,7 @@
  */
 func cgen_aret(n *gc.Node, res *gc.Node) {
 	t := n.Left.Type
-	if gc.Isptr[t.Etype] != 0 {
+	if gc.Isptr[t.Etype] {
 		t = t.Type
 	}
 
@@ -466,7 +466,7 @@
 	case gc.TINT32,
 		gc.TUINT32:
 		var p *obj.Prog
-		if gc.Issigned[t.Etype] != 0 {
+		if gc.Issigned[t.Etype] {
 			p = gins(arm.AMULL, &n2, nil)
 		} else {
 			p = gins(arm.AMULLU, &n2, nil)
@@ -532,13 +532,13 @@
 		if sc == 0 {
 		} else // nothing to do
 		if sc >= uint64(nl.Type.Width*8) {
-			if op == gc.ORSH && gc.Issigned[nl.Type.Etype] != 0 {
+			if op == gc.ORSH && gc.Issigned[nl.Type.Etype] {
 				gshift(arm.AMOVW, &n1, arm.SHIFT_AR, int32(w), &n1)
 			} else {
 				gins(arm.AEOR, &n1, &n1)
 			}
 		} else {
-			if op == gc.ORSH && gc.Issigned[nl.Type.Etype] != 0 {
+			if op == gc.ORSH && gc.Issigned[nl.Type.Etype] {
 				gshift(arm.AMOVW, &n1, arm.SHIFT_AR, int32(sc), &n1)
 			} else if op == gc.ORSH {
 				gshift(arm.AMOVW, &n1, arm.SHIFT_LR, int32(sc), &n1) // OLSH
@@ -617,7 +617,7 @@
 	if op == gc.ORSH {
 		var p1 *obj.Prog
 		var p2 *obj.Prog
-		if gc.Issigned[nl.Type.Etype] != 0 {
+		if gc.Issigned[nl.Type.Etype] {
 			p1 = gshift(arm.AMOVW, &n2, arm.SHIFT_AR, int32(w)-1, &n2)
 			p2 = gregshift(arm.AMOVW, &n2, arm.SHIFT_AR, &n1, &n2)
 		} else {
diff --git a/src/cmd/5g/gsubr.go b/src/cmd/5g/gsubr.go
index 424e164..1df0f49 100644
--- a/src/cmd/5g/gsubr.go
+++ b/src/cmd/5g/gsubr.go
@@ -324,7 +324,7 @@
 	tt := gc.Simsimtype(t.Type)
 	cvt := t.Type
 
-	if gc.Iscomplex[ft] != 0 || gc.Iscomplex[tt] != 0 {
+	if gc.Iscomplex[ft] || gc.Iscomplex[tt] {
 		gc.Complexmove(f, t)
 		return
 	}
diff --git a/src/cmd/6g/cgen.go b/src/cmd/6g/cgen.go
index 05bc55b..696e12c 100644
--- a/src/cmd/6g/cgen.go
+++ b/src/cmd/6g/cgen.go
@@ -127,7 +127,7 @@
 			f = 0
 		}
 
-		if gc.Iscomplex[n.Type.Etype] == 0 {
+		if !gc.Iscomplex[n.Type.Etype] {
 			a := optoas(gc.OAS, res.Type)
 			var addr obj.Addr
 			if sudoaddable(a, res, &addr) {
@@ -202,7 +202,7 @@
 		}
 	}
 
-	if gc.Iscomplex[n.Type.Etype] == 0 {
+	if !gc.Iscomplex[n.Type.Etype] {
 		a := optoas(gc.OAS, n.Type)
 		var addr obj.Addr
 		if sudoaddable(a, n, &addr) {
@@ -269,7 +269,7 @@
 		return
 
 	case gc.OMINUS:
-		if gc.Isfloat[nl.Type.Etype] != 0 {
+		if gc.Isfloat[nl.Type.Etype] {
 			nr = gc.Nodintconst(-1)
 			gc.Convlit(&nr, n.Type)
 			a = optoas(gc.OMUL, nl.Type)
@@ -489,7 +489,7 @@
 
 	case gc.OMOD,
 		gc.ODIV:
-		if gc.Isfloat[n.Type.Etype] != 0 {
+		if gc.Isfloat[n.Type.Etype] {
 			a = optoas(int(n.Op), nl.Type)
 			goto abop
 		}
@@ -777,7 +777,7 @@
 		// type of the index
 		t := gc.Types[gc.TUINT64]
 
-		if gc.Issigned[n1.Type.Etype] != 0 {
+		if gc.Issigned[n1.Type.Etype] {
 			t = gc.Types[gc.TINT64]
 		}
 
@@ -1053,10 +1053,10 @@
 	// Could do the same for slice except that we need
 	// to use the real index for the bounds checking.
 	case gc.OINDEX:
-		if gc.Isfixedarray(n.Left.Type) || (gc.Isptr[n.Left.Type.Etype] != 0 && gc.Isfixedarray(n.Left.Left.Type)) {
+		if gc.Isfixedarray(n.Left.Type) || (gc.Isptr[n.Left.Type.Etype] && gc.Isfixedarray(n.Left.Left.Type)) {
 			if gc.Isconst(n.Right, gc.CTINT) {
 				// Compute &a.
-				if gc.Isptr[n.Left.Type.Etype] == 0 {
+				if !gc.Isptr[n.Left.Type.Etype] {
 					igen(n.Left, a, res)
 				} else {
 					var n1 gc.Node
@@ -1200,7 +1200,7 @@
 		gc.OGE:
 		a := int(n.Op)
 		if !true_ {
-			if gc.Isfloat[nr.Type.Etype] != 0 {
+			if gc.Isfloat[nr.Type.Etype] {
 				// brcom is not valid on floats when NaN is involved.
 				p1 := gc.Gbranch(obj.AJMP, nil, 0)
 
@@ -1266,7 +1266,7 @@
 			break
 		}
 
-		if gc.Iscomplex[nl.Type.Etype] != 0 {
+		if gc.Iscomplex[nl.Type.Etype] {
 			gc.Complexbool(a, nl, nr, true_, likely, to)
 			break
 		}
@@ -1309,7 +1309,7 @@
 		l := &n1
 
 		r := &n2
-		if gc.Isfloat[nl.Type.Etype] != 0 && (a == gc.OGT || a == gc.OGE) {
+		if gc.Isfloat[nl.Type.Etype] && (a == gc.OGT || a == gc.OGE) {
 			l = &n2
 			r = &n1
 			a = gc.Brrev(a)
@@ -1317,7 +1317,7 @@
 
 		gins(optoas(gc.OCMP, nr.Type), l, r)
 
-		if gc.Isfloat[nr.Type.Etype] != 0 && (n.Op == gc.OEQ || n.Op == gc.ONE) {
+		if gc.Isfloat[nr.Type.Etype] && (n.Op == gc.OEQ || n.Op == gc.ONE) {
 			if n.Op == gc.OEQ {
 				// neither NE nor P
 				p1 := gc.Gbranch(x86.AJNE, nil, -likely)
@@ -1369,7 +1369,7 @@
 
 	case gc.ODOT:
 		t := n.Left.Type
-		if gc.Isptr[t.Etype] != 0 {
+		if gc.Isptr[t.Etype] {
 			break
 		}
 		off := stkof(n.Left)
@@ -1396,7 +1396,7 @@
 		gc.OCALLINTER,
 		gc.OCALLFUNC:
 		t := n.Left.Type
-		if gc.Isptr[t.Etype] != 0 {
+		if gc.Isptr[t.Etype] {
 			t = t.Type
 		}
 
diff --git a/src/cmd/6g/ggen.go b/src/cmd/6g/ggen.go
index c278f02..fa526de 100644
--- a/src/cmd/6g/ggen.go
+++ b/src/cmd/6g/ggen.go
@@ -387,7 +387,7 @@
  */
 func cgen_aret(n *gc.Node, res *gc.Node) {
 	t := n.Left.Type
-	if gc.Isptr[t.Etype] != 0 {
+	if gc.Isptr[t.Etype] {
 		t = t.Type
 	}
 
@@ -456,7 +456,7 @@
 
 	t0 := t
 	check := 0
-	if gc.Issigned[t.Etype] != 0 {
+	if gc.Issigned[t.Etype] {
 		check = 1
 		if gc.Isconst(nl, gc.CTINT) && gc.Mpgetfix(nl.Val.U.Xval) != -(1<<uint64(t.Width*8-1)) {
 			check = 0
@@ -466,7 +466,7 @@
 	}
 
 	if t.Width < 4 {
-		if gc.Issigned[t.Etype] != 0 {
+		if gc.Issigned[t.Etype] {
 			t = gc.Types[gc.TINT32]
 		} else {
 			t = gc.Types[gc.TUINT32]
@@ -543,7 +543,7 @@
 	var olddx gc.Node
 	var dx gc.Node
 	savex(x86.REG_DX, &dx, &olddx, res, t)
-	if gc.Issigned[t.Etype] == 0 {
+	if !gc.Issigned[t.Etype] {
 		gc.Nodconst(&n4, t, 0)
 		gmove(&n4, &dx)
 	} else {
@@ -873,7 +873,7 @@
 		gc.Nodconst(&n3, tcount, nl.Type.Width*8)
 		gins(optoas(gc.OCMP, tcount), &n1, &n3)
 		p1 := gc.Gbranch(optoas(gc.OLT, tcount), nil, +1)
-		if op == gc.ORSH && gc.Issigned[nl.Type.Etype] != 0 {
+		if op == gc.ORSH && gc.Issigned[nl.Type.Etype] {
 			gc.Nodconst(&n3, gc.Types[gc.TUINT32], nl.Type.Width*8-1)
 			gins(a, &n3, &n2)
 		} else {
@@ -924,7 +924,7 @@
 	// perform full-width multiplication.
 	t := gc.Types[gc.TUINT64]
 
-	if gc.Issigned[nl.Type.Etype] != 0 {
+	if gc.Issigned[nl.Type.Etype] {
 		t = gc.Types[gc.TINT64]
 	}
 	var n1 gc.Node
diff --git a/src/cmd/6g/gsubr.go b/src/cmd/6g/gsubr.go
index 807b6b2..9434dff 100644
--- a/src/cmd/6g/gsubr.go
+++ b/src/cmd/6g/gsubr.go
@@ -308,7 +308,7 @@
 	tt := gc.Simsimtype(t.Type)
 	cvt := t.Type
 
-	if gc.Iscomplex[ft] != 0 || gc.Iscomplex[tt] != 0 {
+	if gc.Iscomplex[ft] || gc.Iscomplex[tt] {
 		gc.Complexmove(f, t)
 		return
 	}
@@ -330,13 +330,13 @@
 		// some constants can't move directly to memory.
 		if gc.Ismem(t) {
 			// float constants come from memory.
-			if gc.Isfloat[tt] != 0 {
+			if gc.Isfloat[tt] {
 				goto hard
 			}
 
 			// 64-bit immediates are really 32-bit sign-extended
 			// unless moving into a register.
-			if gc.Isint[tt] != 0 {
+			if gc.Isint[tt] {
 				if gc.Mpcmpfixfix(con.Val.U.Xval, gc.Minintval[gc.TINT32]) < 0 {
 					goto hard
 				}
diff --git a/src/cmd/8g/cgen.go b/src/cmd/8g/cgen.go
index 1be0928..a2bd6ec 100644
--- a/src/cmd/8g/cgen.go
+++ b/src/cmd/8g/cgen.go
@@ -31,7 +31,7 @@
 
 	gc.Tempname(n1, n.Type)
 	cgen(n, n1)
-	if n.Type.Width <= int64(gc.Widthptr) || gc.Isfloat[n.Type.Etype] != 0 {
+	if n.Type.Width <= int64(gc.Widthptr) || gc.Isfloat[n.Type.Etype] {
 		n2 := *n1
 		regalloc(n1, n.Type, rg)
 		gmove(&n2, n1)
@@ -210,7 +210,7 @@
 		}
 	}
 
-	if nl != nil && gc.Isfloat[n.Type.Etype] != 0 && gc.Isfloat[nl.Type.Etype] != 0 {
+	if nl != nil && gc.Isfloat[n.Type.Etype] && gc.Isfloat[nl.Type.Etype] {
 		cgen_float(n, res)
 		return
 	}
@@ -712,7 +712,7 @@
 		// i is in register n1, extend to 32 bits.
 		t := gc.Types[gc.TUINT32]
 
-		if gc.Issigned[n1.Type.Etype] != 0 {
+		if gc.Issigned[n1.Type.Etype] {
 			t = gc.Types[gc.TINT32]
 		}
 
@@ -820,7 +820,7 @@
 
 	case gc.ODOTPTR:
 		t := nl.Type
-		if gc.Isptr[t.Etype] == 0 {
+		if !gc.Isptr[t.Etype] {
 			gc.Fatal("agen: not ptr %v", gc.Nconv(n, 0))
 		}
 		cgen(nl, res)
@@ -925,10 +925,10 @@
 	// Could do the same for slice except that we need
 	// to use the real index for the bounds checking.
 	case gc.OINDEX:
-		if gc.Isfixedarray(n.Left.Type) || (gc.Isptr[n.Left.Type.Etype] != 0 && gc.Isfixedarray(n.Left.Left.Type)) {
+		if gc.Isfixedarray(n.Left.Type) || (gc.Isptr[n.Left.Type.Etype] && gc.Isfixedarray(n.Left.Left.Type)) {
 			if gc.Isconst(n.Right, gc.CTINT) {
 				// Compute &a.
-				if gc.Isptr[n.Left.Type.Etype] == 0 {
+				if !gc.Isptr[n.Left.Type.Etype] {
 					igen(n.Left, a, res)
 				} else {
 					var n1 gc.Node
@@ -1007,7 +1007,7 @@
 	nl := n.Left
 	nr := (*gc.Node)(nil)
 
-	if nl != nil && gc.Isfloat[nl.Type.Etype] != 0 {
+	if nl != nil && gc.Isfloat[nl.Type.Etype] {
 		bgen_float(n, bool2int(true_), likely, to)
 		return
 	}
@@ -1138,7 +1138,7 @@
 			break
 		}
 
-		if gc.Iscomplex[nl.Type.Etype] != 0 {
+		if gc.Iscomplex[nl.Type.Etype] {
 			gc.Complexbool(a, nl, nr, true_, likely, to)
 			break
 		}
@@ -1249,7 +1249,7 @@
 
 	case gc.ODOT:
 		t := n.Left.Type
-		if gc.Isptr[t.Etype] != 0 {
+		if gc.Isptr[t.Etype] {
 			break
 		}
 		off := stkof(n.Left)
@@ -1276,7 +1276,7 @@
 		gc.OCALLINTER,
 		gc.OCALLFUNC:
 		t := n.Left.Type
-		if gc.Isptr[t.Etype] != 0 {
+		if gc.Isptr[t.Etype] {
 			t = t.Type
 		}
 
diff --git a/src/cmd/8g/ggen.go b/src/cmd/8g/ggen.go
index 7aba85e..27938c7 100644
--- a/src/cmd/8g/ggen.go
+++ b/src/cmd/8g/ggen.go
@@ -446,7 +446,7 @@
  */
 func cgen_aret(n *gc.Node, res *gc.Node) {
 	t := n.Left.Type
-	if gc.Isptr[t.Etype] != 0 {
+	if gc.Isptr[t.Etype] {
 		t = t.Type
 	}
 
@@ -518,7 +518,7 @@
 
 	t0 := t
 	check := 0
-	if gc.Issigned[t.Etype] != 0 {
+	if gc.Issigned[t.Etype] {
 		check = 1
 		if gc.Isconst(nl, gc.CTINT) && gc.Mpgetfix(nl.Val.U.Xval) != -1<<uint64(t.Width*8-1) {
 			check = 0
@@ -528,7 +528,7 @@
 	}
 
 	if t.Width < 4 {
-		if gc.Issigned[t.Etype] != 0 {
+		if gc.Issigned[t.Etype] {
 			t = gc.Types[gc.TINT32]
 		} else {
 			t = gc.Types[gc.TUINT32]
@@ -602,7 +602,7 @@
 		gc.Patch(p1, gc.Pc)
 	}
 
-	if gc.Issigned[t.Etype] == 0 {
+	if !gc.Issigned[t.Etype] {
 		var nz gc.Node
 		gc.Nodconst(&nz, t, 0)
 		gmove(&nz, dx)
@@ -658,7 +658,7 @@
 	}
 
 	var t *gc.Type
-	if gc.Issigned[nl.Type.Etype] != 0 {
+	if gc.Issigned[nl.Type.Etype] {
 		t = gc.Types[gc.TINT32]
 	} else {
 		t = gc.Types[gc.TUINT32]
@@ -776,7 +776,7 @@
 			p1 = gc.Gbranch(optoas(gc.OLT, gc.Types[gc.TUINT32]), nil, +1)
 		}
 
-		if op == gc.ORSH && gc.Issigned[nl.Type.Etype] != 0 {
+		if op == gc.ORSH && gc.Issigned[nl.Type.Etype] {
 			gins(a, ncon(uint32(w)-1), &n2)
 		} else {
 			gmove(ncon(0), &n2)
@@ -807,7 +807,7 @@
 	// copy from byte to full registers
 	t := gc.Types[gc.TUINT32]
 
-	if gc.Issigned[nl.Type.Etype] != 0 {
+	if gc.Issigned[nl.Type.Etype] {
 		t = gc.Types[gc.TINT32]
 	}
 
diff --git a/src/cmd/8g/gsubr.go b/src/cmd/8g/gsubr.go
index ec00779..0d26a41 100644
--- a/src/cmd/8g/gsubr.go
+++ b/src/cmd/8g/gsubr.go
@@ -890,12 +890,12 @@
 	tt := gc.Simsimtype(t.Type)
 	cvt := t.Type
 
-	if gc.Iscomplex[ft] != 0 || gc.Iscomplex[tt] != 0 {
+	if gc.Iscomplex[ft] || gc.Iscomplex[tt] {
 		gc.Complexmove(f, t)
 		return
 	}
 
-	if gc.Isfloat[ft] != 0 || gc.Isfloat[tt] != 0 {
+	if gc.Isfloat[ft] || gc.Isfloat[tt] {
 		floatmove(f, t)
 		return
 	}
@@ -904,7 +904,7 @@
 	// except 64-bit, which always copies via registers anyway.
 	var r1 gc.Node
 	var a int
-	if gc.Isint[ft] != 0 && gc.Isint[tt] != 0 && !gc.Is64(f.Type) && !gc.Is64(t.Type) && gc.Ismem(f) && gc.Ismem(t) {
+	if gc.Isint[ft] && gc.Isint[tt] && !gc.Is64(f.Type) && !gc.Is64(t.Type) && gc.Ismem(f) && gc.Ismem(t) {
 		goto hard
 	}
 
@@ -1173,7 +1173,7 @@
 	cvt := t.Type
 
 	// cannot have two floating point memory operands.
-	if gc.Isfloat[ft] != 0 && gc.Isfloat[tt] != 0 && gc.Ismem(f) && gc.Ismem(t) {
+	if gc.Isfloat[ft] && gc.Isfloat[tt] && gc.Ismem(f) && gc.Ismem(t) {
 		goto hard
 	}
 
@@ -1187,7 +1187,7 @@
 		// some constants can't move directly to memory.
 		if gc.Ismem(t) {
 			// float constants come from memory.
-			if gc.Isfloat[tt] != 0 {
+			if gc.Isfloat[tt] {
 				goto hard
 			}
 		}
diff --git a/src/cmd/9g/cgen.go b/src/cmd/9g/cgen.go
index 61a93da..aca5b99 100644
--- a/src/cmd/9g/cgen.go
+++ b/src/cmd/9g/cgen.go
@@ -124,7 +124,7 @@
 			f = 0
 		}
 
-		if gc.Iscomplex[n.Type.Etype] == 0 {
+		if !gc.Iscomplex[n.Type.Etype] {
 			a := optoas(gc.OAS, res.Type)
 			var addr obj.Addr
 			if sudoaddable(a, res, &addr) {
@@ -209,7 +209,7 @@
 		}
 	}
 
-	if gc.Iscomplex[n.Type.Etype] == 0 {
+	if !gc.Iscomplex[n.Type.Etype] {
 		a := optoas(gc.OAS, n.Type)
 		var addr obj.Addr
 		if sudoaddable(a, n, &addr) {
@@ -280,7 +280,7 @@
 		return
 
 	case gc.OMINUS:
-		if gc.Isfloat[nl.Type.Etype] != 0 {
+		if gc.Isfloat[nl.Type.Etype] {
 			nr = gc.Nodintconst(-1)
 			gc.Convlit(&nr, n.Type)
 			a = optoas(gc.OMUL, nl.Type)
@@ -495,7 +495,7 @@
 
 	case gc.OMOD,
 		gc.ODIV:
-		if gc.Isfloat[n.Type.Etype] != 0 {
+		if gc.Isfloat[n.Type.Etype] {
 			a = optoas(int(n.Op), nl.Type)
 			goto abop
 		}
@@ -1071,10 +1071,10 @@
 	// Could do the same for slice except that we need
 	// to use the real index for the bounds checking.
 	case gc.OINDEX:
-		if gc.Isfixedarray(n.Left.Type) || (gc.Isptr[n.Left.Type.Etype] != 0 && gc.Isfixedarray(n.Left.Left.Type)) {
+		if gc.Isfixedarray(n.Left.Type) || (gc.Isptr[n.Left.Type.Etype] && gc.Isfixedarray(n.Left.Left.Type)) {
 			if gc.Isconst(n.Right, gc.CTINT) {
 				// Compute &a.
-				if gc.Isptr[n.Left.Type.Etype] == 0 {
+				if !gc.Isptr[n.Left.Type.Etype] {
 					igen(n.Left, a, res)
 				} else {
 					var n1 gc.Node
@@ -1216,7 +1216,7 @@
 		gc.OGE:
 		a := int(n.Op)
 		if !true_ {
-			if gc.Isfloat[nr.Type.Etype] != 0 {
+			if gc.Isfloat[nr.Type.Etype] {
 				// brcom is not valid on floats when NaN is involved.
 				p1 := gc.Gbranch(ppc64.ABR, nil, 0)
 
@@ -1290,7 +1290,7 @@
 			break
 		}
 
-		if gc.Iscomplex[nl.Type.Etype] != 0 {
+		if gc.Iscomplex[nl.Type.Etype] {
 			gc.Complexbool(a, nl, nr, true_, likely, to)
 			break
 		}
@@ -1335,7 +1335,7 @@
 		l := &n1
 		r := &n2
 		gins(optoas(gc.OCMP, nr.Type), l, r)
-		if gc.Isfloat[nr.Type.Etype] != 0 && (a == gc.OLE || a == gc.OGE) {
+		if gc.Isfloat[nr.Type.Etype] && (a == gc.OLE || a == gc.OGE) {
 			// To get NaN right, must rewrite x <= y into separate x < y or x = y.
 			switch a {
 			case gc.OLE:
@@ -1370,7 +1370,7 @@
 
 	case gc.ODOT:
 		t := n.Left.Type
-		if gc.Isptr[t.Etype] != 0 {
+		if gc.Isptr[t.Etype] {
 			break
 		}
 		off := stkof(n.Left)
@@ -1397,7 +1397,7 @@
 		gc.OCALLINTER,
 		gc.OCALLFUNC:
 		t := n.Left.Type
-		if gc.Isptr[t.Etype] != 0 {
+		if gc.Isptr[t.Etype] {
 			t = t.Type
 		}
 
diff --git a/src/cmd/9g/ggen.go b/src/cmd/9g/ggen.go
index bd22771..dc98963 100644
--- a/src/cmd/9g/ggen.go
+++ b/src/cmd/9g/ggen.go
@@ -391,7 +391,7 @@
  */
 func cgen_aret(n *gc.Node, res *gc.Node) {
 	t := n.Left.Type
-	if gc.Isptr[t.Etype] != 0 {
+	if gc.Isptr[t.Etype] {
 		t = t.Type
 	}
 
@@ -459,7 +459,7 @@
 
 	t0 := t
 	check := 0
-	if gc.Issigned[t.Etype] != 0 {
+	if gc.Issigned[t.Etype] {
 		check = 1
 		if gc.Isconst(nl, gc.CTINT) && gc.Mpgetfix(nl.Val.U.Xval) != -(1<<uint64(t.Width*8-1)) {
 			check = 0
@@ -469,7 +469,7 @@
 	}
 
 	if t.Width < 8 {
-		if gc.Issigned[t.Etype] != 0 {
+		if gc.Issigned[t.Etype] {
 			t = gc.Types[gc.TINT64]
 		} else {
 			t = gc.Types[gc.TUINT64]
@@ -615,7 +615,7 @@
 
 	case gc.TINT64,
 		gc.TUINT64:
-		if gc.Issigned[t.Etype] != 0 {
+		if gc.Issigned[t.Etype] {
 			gins(ppc64.AMULHD, &n2, &n1)
 		} else {
 			gins(ppc64.AMULHDU, &n2, &n1)
@@ -706,7 +706,7 @@
 		gc.Nodconst(&n3, tcount, nl.Type.Width*8)
 		gins(optoas(gc.OCMP, tcount), &n1, &n3)
 		p1 := (*obj.Prog)(gc.Gbranch(optoas(gc.OLT, tcount), nil, +1))
-		if op == gc.ORSH && gc.Issigned[nl.Type.Etype] != 0 {
+		if op == gc.ORSH && gc.Issigned[nl.Type.Etype] {
 			gc.Nodconst(&n3, gc.Types[gc.TUINT32], nl.Type.Width*8-1)
 			gins(a, &n3, &n2)
 		} else {
diff --git a/src/cmd/9g/gsubr.go b/src/cmd/9g/gsubr.go
index 74a312a..2c51d06 100644
--- a/src/cmd/9g/gsubr.go
+++ b/src/cmd/9g/gsubr.go
@@ -325,7 +325,7 @@
 	tt := int(gc.Simsimtype(t.Type))
 	cvt := (*gc.Type)(t.Type)
 
-	if gc.Iscomplex[ft] != 0 || gc.Iscomplex[tt] != 0 {
+	if gc.Iscomplex[ft] || gc.Iscomplex[tt] {
 		gc.Complexmove(f, t)
 		return
 	}
diff --git a/src/cmd/internal/gc/align.go b/src/cmd/internal/gc/align.go
index a588ca3..1171300 100644
--- a/src/cmd/internal/gc/align.go
+++ b/src/cmd/internal/gc/align.go
@@ -450,95 +450,95 @@
 	}
 
 	for i := TINT8; i <= TUINT64; i++ {
-		Isint[i] = 1
+		Isint[i] = true
 	}
-	Isint[TINT] = 1
-	Isint[TUINT] = 1
-	Isint[TUINTPTR] = 1
+	Isint[TINT] = true
+	Isint[TUINT] = true
+	Isint[TUINTPTR] = true
 
-	Isfloat[TFLOAT32] = 1
-	Isfloat[TFLOAT64] = 1
+	Isfloat[TFLOAT32] = true
+	Isfloat[TFLOAT64] = true
 
-	Iscomplex[TCOMPLEX64] = 1
-	Iscomplex[TCOMPLEX128] = 1
+	Iscomplex[TCOMPLEX64] = true
+	Iscomplex[TCOMPLEX128] = true
 
-	Isptr[TPTR32] = 1
-	Isptr[TPTR64] = 1
+	Isptr[TPTR32] = true
+	Isptr[TPTR64] = true
 
-	isforw[TFORW] = 1
+	isforw[TFORW] = true
 
-	Issigned[TINT] = 1
-	Issigned[TINT8] = 1
-	Issigned[TINT16] = 1
-	Issigned[TINT32] = 1
-	Issigned[TINT64] = 1
+	Issigned[TINT] = true
+	Issigned[TINT8] = true
+	Issigned[TINT16] = true
+	Issigned[TINT32] = true
+	Issigned[TINT64] = true
 
 	/*
 	 * initialize okfor
 	 */
 	for i := 0; i < NTYPE; i++ {
-		if Isint[i] != 0 || i == TIDEAL {
-			okforeq[i] = 1
-			okforcmp[i] = 1
-			okforarith[i] = 1
-			okforadd[i] = 1
-			okforand[i] = 1
-			okforconst[i] = 1
-			issimple[i] = 1
+		if Isint[i] || i == TIDEAL {
+			okforeq[i] = true
+			okforcmp[i] = true
+			okforarith[i] = true
+			okforadd[i] = true
+			okforand[i] = true
+			okforconst[i] = true
+			issimple[i] = true
 			Minintval[i] = new(Mpint)
 			Maxintval[i] = new(Mpint)
 		}
 
-		if Isfloat[i] != 0 {
-			okforeq[i] = 1
-			okforcmp[i] = 1
-			okforadd[i] = 1
-			okforarith[i] = 1
-			okforconst[i] = 1
-			issimple[i] = 1
+		if Isfloat[i] {
+			okforeq[i] = true
+			okforcmp[i] = true
+			okforadd[i] = true
+			okforarith[i] = true
+			okforconst[i] = true
+			issimple[i] = true
 			minfltval[i] = new(Mpflt)
 			maxfltval[i] = new(Mpflt)
 		}
 
-		if Iscomplex[i] != 0 {
-			okforeq[i] = 1
-			okforadd[i] = 1
-			okforarith[i] = 1
-			okforconst[i] = 1
-			issimple[i] = 1
+		if Iscomplex[i] {
+			okforeq[i] = true
+			okforadd[i] = true
+			okforarith[i] = true
+			okforconst[i] = true
+			issimple[i] = true
 		}
 	}
 
-	issimple[TBOOL] = 1
+	issimple[TBOOL] = true
 
-	okforadd[TSTRING] = 1
+	okforadd[TSTRING] = true
 
-	okforbool[TBOOL] = 1
+	okforbool[TBOOL] = true
 
-	okforcap[TARRAY] = 1
-	okforcap[TCHAN] = 1
+	okforcap[TARRAY] = true
+	okforcap[TCHAN] = true
 
-	okforconst[TBOOL] = 1
-	okforconst[TSTRING] = 1
+	okforconst[TBOOL] = true
+	okforconst[TSTRING] = true
 
-	okforlen[TARRAY] = 1
-	okforlen[TCHAN] = 1
-	okforlen[TMAP] = 1
-	okforlen[TSTRING] = 1
+	okforlen[TARRAY] = true
+	okforlen[TCHAN] = true
+	okforlen[TMAP] = true
+	okforlen[TSTRING] = true
 
-	okforeq[TPTR32] = 1
-	okforeq[TPTR64] = 1
-	okforeq[TUNSAFEPTR] = 1
-	okforeq[TINTER] = 1
-	okforeq[TCHAN] = 1
-	okforeq[TSTRING] = 1
-	okforeq[TBOOL] = 1
-	okforeq[TMAP] = 1    // nil only; refined in typecheck
-	okforeq[TFUNC] = 1   // nil only; refined in typecheck
-	okforeq[TARRAY] = 1  // nil slice only; refined in typecheck
-	okforeq[TSTRUCT] = 1 // it's complicated; refined in typecheck
+	okforeq[TPTR32] = true
+	okforeq[TPTR64] = true
+	okforeq[TUNSAFEPTR] = true
+	okforeq[TINTER] = true
+	okforeq[TCHAN] = true
+	okforeq[TSTRING] = true
+	okforeq[TBOOL] = true
+	okforeq[TMAP] = true    // nil only; refined in typecheck
+	okforeq[TFUNC] = true   // nil only; refined in typecheck
+	okforeq[TARRAY] = true  // nil slice only; refined in typecheck
+	okforeq[TSTRUCT] = true // it's complicated; refined in typecheck
 
-	okforcmp[TSTRING] = 1
+	okforcmp[TSTRING] = true
 
 	var i int
 	for i = 0; i < len(okfor); i++ {
@@ -580,13 +580,13 @@
 	okfor[OLEN] = okforlen[:]
 
 	// comparison
-	iscmp[OLT] = 1
+	iscmp[OLT] = true
 
-	iscmp[OGT] = 1
-	iscmp[OGE] = 1
-	iscmp[OLE] = 1
-	iscmp[OEQ] = 1
-	iscmp[ONE] = 1
+	iscmp[OGT] = true
+	iscmp[OGE] = true
+	iscmp[OLE] = true
+	iscmp[OEQ] = true
+	iscmp[ONE] = true
 
 	mpatofix(Maxintval[TINT8], "0x7f")
 	mpatofix(Minintval[TINT8], "-0x80")
diff --git a/src/cmd/internal/gc/closure.go b/src/cmd/internal/gc/closure.go
index 20a0349..d954ad0 100644
--- a/src/cmd/internal/gc/closure.go
+++ b/src/cmd/internal/gc/closure.go
@@ -519,7 +519,7 @@
 		p = fmt.Sprintf("(%v).(%v)-fm", Tconv(rcvrtype, obj.FmtLeft|obj.FmtShort), Sconv(meth.Sym, obj.FmtLeft))
 	}
 	basetype := rcvrtype
-	if Isptr[rcvrtype.Etype] != 0 {
+	if Isptr[rcvrtype.Etype] {
 		basetype = basetype.Type
 	}
 	if basetype.Etype != TINTER && basetype.Sym == nil {
@@ -613,7 +613,7 @@
 	ptr.Used = 1
 	ptr.Curfn = xfunc
 	xfunc.Dcl = list(xfunc.Dcl, ptr)
-	if Isptr[rcvrtype.Etype] != 0 || Isinter(rcvrtype) {
+	if Isptr[rcvrtype.Etype] || Isinter(rcvrtype) {
 		ptr.Ntype = typenod(rcvrtype)
 		body = list(body, Nod(OAS, ptr, cv))
 	} else {
diff --git a/src/cmd/internal/gc/const.go b/src/cmd/internal/gc/const.go
index 4730d7d..0a182f9 100644
--- a/src/cmd/internal/gc/const.go
+++ b/src/cmd/internal/gc/const.go
@@ -87,7 +87,7 @@
 
 		// target is invalid type for a constant?  leave alone.
 	case OLITERAL:
-		if okforconst[t.Etype] == 0 && n.Type.Etype != TNIL {
+		if !okforconst[t.Etype] && n.Type.Etype != TNIL {
 			defaultlit(&n, nil)
 			*np = n
 			return
@@ -100,7 +100,7 @@
 		if t != nil && t.Etype == TIDEAL && n.Val.Ctype != CTINT {
 			n.Val = toint(n.Val)
 		}
-		if t != nil && Isint[t.Etype] == 0 {
+		if t != nil && !Isint[t.Etype] {
 			Yyerror("invalid operation: %v (shift of type %v)", Nconv(n, 0), Tconv(t, 0))
 			t = nil
 		}
@@ -207,7 +207,7 @@
 		CTFLT,
 		CTCPLX:
 		ct := int(n.Val.Ctype)
-		if Isint[et] != 0 {
+		if Isint[et] {
 			switch ct {
 			default:
 				goto bad
@@ -222,7 +222,7 @@
 			case CTINT:
 				overflow(n.Val, t)
 			}
-		} else if Isfloat[et] != 0 {
+		} else if Isfloat[et] {
 			switch ct {
 			default:
 				goto bad
@@ -237,7 +237,7 @@
 			case CTFLT:
 				n.Val.U.Fval = truncfltlit(n.Val.U.Fval, t)
 			}
-		} else if Iscomplex[et] != 0 {
+		} else if Iscomplex[et] {
 			switch ct {
 			default:
 				goto bad
@@ -374,7 +374,7 @@
 	switch v.Ctype {
 	case CTINT,
 		CTRUNE:
-		if Isint[t.Etype] == 0 {
+		if !Isint[t.Etype] {
 			Fatal("overflow: %v integer constant", Tconv(t, 0))
 		}
 		if Mpcmpfixfix(v.U.Xval, Minintval[t.Etype]) < 0 || Mpcmpfixfix(v.U.Xval, Maxintval[t.Etype]) > 0 {
@@ -382,7 +382,7 @@
 		}
 
 	case CTFLT:
-		if Isfloat[t.Etype] == 0 {
+		if !Isfloat[t.Etype] {
 			Fatal("overflow: %v floating-point constant", Tconv(t, 0))
 		}
 		if mpcmpfltflt(v.U.Fval, minfltval[t.Etype]) <= 0 || mpcmpfltflt(v.U.Fval, maxfltval[t.Etype]) >= 0 {
@@ -390,7 +390,7 @@
 		}
 
 	case CTCPLX:
-		if Iscomplex[t.Etype] == 0 {
+		if !Iscomplex[t.Etype] {
 			Fatal("overflow: %v complex constant", Tconv(t, 0))
 		}
 		if mpcmpfltflt(&v.U.Cval.Real, minfltval[t.Etype]) <= 0 || mpcmpfltflt(&v.U.Cval.Real, maxfltval[t.Etype]) >= 0 || mpcmpfltflt(&v.U.Cval.Imag, minfltval[t.Etype]) <= 0 || mpcmpfltflt(&v.U.Cval.Imag, maxfltval[t.Etype]) >= 0 {
@@ -518,7 +518,7 @@
 		if n.Type == nil {
 			return
 		}
-		if okforconst[n.Type.Etype] == 0 && n.Type.Etype != TNIL {
+		if !okforconst[n.Type.Etype] && n.Type.Etype != TNIL {
 			return
 		}
 
@@ -571,7 +571,7 @@
 		return
 	}
 	wl := int(nl.Type.Etype)
-	if Isint[wl] != 0 || Isfloat[wl] != 0 || Iscomplex[wl] != 0 {
+	if Isint[wl] || Isfloat[wl] || Iscomplex[wl] {
 		wl = TIDEAL
 	}
 
@@ -680,7 +680,7 @@
 		return
 	}
 	wr = int(nr.Type.Etype)
-	if Isint[wr] != 0 || Isfloat[wr] != 0 || Iscomplex[wr] != 0 {
+	if Isint[wr] || Isfloat[wr] || Iscomplex[wr] {
 		wr = TIDEAL
 	}
 
@@ -714,7 +714,7 @@
 		defaultlit(&nr, Types[TUINT])
 
 		n.Right = nr
-		if nr.Type != nil && (Issigned[nr.Type.Etype] != 0 || Isint[nr.Type.Etype] == 0) {
+		if nr.Type != nil && (Issigned[nr.Type.Etype] || !Isint[nr.Type.Etype]) {
 			goto illegal
 		}
 		if nl.Val.Ctype != CTRUNE {
@@ -1261,13 +1261,13 @@
 
 num:
 	if t != nil {
-		if Isint[t.Etype] != 0 {
+		if Isint[t.Etype] {
 			t1 = t
 			n.Val = toint(n.Val)
-		} else if Isfloat[t.Etype] != 0 {
+		} else if Isfloat[t.Etype] {
 			t1 = t
 			n.Val = toflt(n.Val)
-		} else if Iscomplex[t.Etype] != 0 {
+		} else if Iscomplex[t.Etype] {
 			t1 = t
 			n.Val = tocplx(n.Val)
 		}
@@ -1432,7 +1432,7 @@
 	con.Type = t
 	con.Val = *val
 
-	if Isint[tt] != 0 {
+	if Isint[tt] {
 		con.Val.Ctype = CTINT
 		con.Val.U.Xval = new(Mpint)
 		var i int64
@@ -1456,7 +1456,7 @@
 		return
 	}
 
-	if Isfloat[tt] != 0 {
+	if Isfloat[tt] {
 		con.Val = toflt(con.Val)
 		if con.Val.Ctype != CTFLT {
 			Fatal("convconst ctype=%d %v", con.Val.Ctype, Tconv(t, 0))
@@ -1467,7 +1467,7 @@
 		return
 	}
 
-	if Iscomplex[tt] != 0 {
+	if Iscomplex[tt] {
 		con.Val = tocplx(con.Val)
 		if tt == TCOMPLEX64 {
 			con.Val.U.Cval.Real = *truncfltlit(&con.Val.U.Cval.Real, Types[TFLOAT32])
@@ -1601,7 +1601,7 @@
 		}
 
 	case OCONV:
-		if okforconst[n.Type.Etype] != 0 && isgoconst(n.Left) {
+		if okforconst[n.Type.Etype] && isgoconst(n.Left) {
 			return true
 		}
 
@@ -1617,7 +1617,7 @@
 		// function calls or channel receive operations.
 		t := l.Type
 
-		if t != nil && Isptr[t.Etype] != 0 {
+		if t != nil && Isptr[t.Etype] {
 			t = t.Type
 		}
 		if Isfixedarray(t) && !hascallchan(l) {
diff --git a/src/cmd/internal/gc/cplx.go b/src/cmd/internal/gc/cplx.go
index 02b6c79..10d1ab0 100644
--- a/src/cmd/internal/gc/cplx.go
+++ b/src/cmd/internal/gc/cplx.go
@@ -233,7 +233,7 @@
 	n.Val.Ctype = CTFLT
 	n.Type = t
 
-	if Isfloat[t.Etype] == 0 {
+	if !Isfloat[t.Etype] {
 		Fatal("nodfconst: bad type %v", Tconv(t, 0))
 	}
 }
@@ -243,13 +243,13 @@
  */
 func Complexop(n *Node, res *Node) bool {
 	if n != nil && n.Type != nil {
-		if Iscomplex[n.Type.Etype] != 0 {
+		if Iscomplex[n.Type.Etype] {
 			goto maybe
 		}
 	}
 
 	if res != nil && res.Type != nil {
-		if Iscomplex[res.Type.Etype] != 0 {
+		if Iscomplex[res.Type.Etype] {
 			goto maybe
 		}
 	}
diff --git a/src/cmd/internal/gc/dcl.go b/src/cmd/internal/gc/dcl.go
index ceececd..0eef37b 100644
--- a/src/cmd/internal/gc/dcl.go
+++ b/src/cmd/internal/gc/dcl.go
@@ -778,14 +778,14 @@
 		return
 	}
 
-	if t.Sym == nil && Isptr[t.Etype] != 0 {
+	if t.Sym == nil && Isptr[t.Etype] {
 		t = t.Type
 		if t.Etype == TINTER {
 			Yyerror("embedded type cannot be a pointer to interface")
 		}
 	}
 
-	if Isptr[t.Etype] != 0 {
+	if Isptr[t.Etype] {
 		Yyerror("embedded type cannot be a pointer")
 	} else if t.Etype == TFORW && t.Embedlineno == 0 {
 		t.Embedlineno = lineno
@@ -1178,7 +1178,7 @@
 		return false
 	}
 	t := rcvr.Type
-	if Isptr[t.Etype] == 0 {
+	if !Isptr[t.Etype] {
 		return false
 	}
 	t = t.Type
@@ -1241,7 +1241,7 @@
 		goto bad
 	}
 	s = t.Sym
-	if s == nil && Isptr[t.Etype] != 0 {
+	if s == nil && Isptr[t.Etype] {
 		t = t.Type
 		if t == nil {
 			goto bad
@@ -1269,13 +1269,13 @@
 	}
 
 	if (spkg == nil || nsym.Pkg != spkg) && !exportname(nsym.Name) {
-		if t0.Sym == nil && Isptr[t0.Etype] != 0 {
+		if t0.Sym == nil && Isptr[t0.Etype] {
 			p = fmt.Sprintf("(%v).%s.%s%s", Tconv(t0, obj.FmtLeft|obj.FmtShort), nsym.Pkg.Prefix, nsym.Name, suffix)
 		} else {
 			p = fmt.Sprintf("%v.%s.%s%s", Tconv(t0, obj.FmtLeft|obj.FmtShort), nsym.Pkg.Prefix, nsym.Name, suffix)
 		}
 	} else {
-		if t0.Sym == nil && Isptr[t0.Etype] != 0 {
+		if t0.Sym == nil && Isptr[t0.Etype] {
 			p = fmt.Sprintf("(%v).%s%s", Tconv(t0, obj.FmtLeft|obj.FmtShort), nsym.Name, suffix)
 		} else {
 			p = fmt.Sprintf("%v.%s%s", Tconv(t0, obj.FmtLeft|obj.FmtShort), nsym.Name, suffix)
@@ -1358,7 +1358,7 @@
 			return
 		}
 		if t != nil {
-			if Isptr[t.Etype] != 0 {
+			if Isptr[t.Etype] {
 				if t.Sym != nil {
 					Yyerror("invalid receiver type %v (%v is a pointer type)", Tconv(pa, 0), Tconv(t, 0))
 					return
@@ -1375,7 +1375,7 @@
 				return
 			}
 
-			if Isptr[t.Etype] != 0 {
+			if Isptr[t.Etype] {
 				Yyerror("invalid receiver type %v (%v is a pointer type)", Tconv(pa, 0), Tconv(t, 0))
 				return
 			}
diff --git a/src/cmd/internal/gc/export.go b/src/cmd/internal/gc/export.go
index 2467086..17037f6 100644
--- a/src/cmd/internal/gc/export.go
+++ b/src/cmd/internal/gc/export.go
@@ -134,7 +134,7 @@
 		t := n.Left.Type
 
 		if t != Types[t.Etype] && t != idealbool && t != idealstring {
-			if Isptr[t.Etype] != 0 {
+			if Isptr[t.Etype] {
 				t = t.Type
 			}
 			if t != nil && t.Sym != nil && t.Sym.Def != nil && !exportedsym(t.Sym) {
@@ -148,7 +148,7 @@
 	case OLITERAL:
 		t := n.Type
 		if t != Types[n.Type.Etype] && t != idealbool && t != idealstring {
-			if Isptr[t.Etype] != 0 {
+			if Isptr[t.Etype] {
 				t = t.Type
 			}
 			if t != nil && t.Sym != nil && t.Sym.Def != nil && !exportedsym(t.Sym) {
diff --git a/src/cmd/internal/gc/fmt.go b/src/cmd/internal/gc/fmt.go
index 869aaa0..6fe4a33 100644
--- a/src/cmd/internal/gc/fmt.go
+++ b/src/cmd/internal/gc/fmt.go
@@ -1202,7 +1202,7 @@
 		if n.Type != nil && n.Type != Types[n.Type.Etype] && n.Type != idealbool && n.Type != idealstring {
 			// Need parens when type begins with what might
 			// be misinterpreted as a unary operator: * or <-.
-			if Isptr[n.Type.Etype] != 0 || (n.Type.Etype == TCHAN && n.Type.Chan == Crecv) {
+			if Isptr[n.Type.Etype] || (n.Type.Etype == TCHAN && n.Type.Chan == Crecv) {
 				return fmt.Sprintf("(%v)(%v)", Tconv(n.Type, 0), Vconv(&n.Val, 0))
 			} else {
 				return fmt.Sprintf("%v(%v)", Tconv(n.Type, 0), Vconv(&n.Val, 0))
@@ -1227,7 +1227,7 @@
 		// but for export, this should be rendered as (*pkg.T).meth.
 		// These nodes have the special property that they are names with a left OTYPE and a right ONAME.
 		if fmtmode == FExp && n.Left != nil && n.Left.Op == OTYPE && n.Right != nil && n.Right.Op == ONAME {
-			if Isptr[n.Left.Type.Etype] != 0 {
+			if Isptr[n.Left.Type.Etype] {
 				return fmt.Sprintf("(%v).%v", Tconv(n.Left.Type, 0), Sconv(n.Right.Sym, obj.FmtShort|obj.FmtByte))
 			} else {
 				return fmt.Sprintf("%v.%v", Tconv(n.Left.Type, 0), Sconv(n.Right.Sym, obj.FmtShort|obj.FmtByte))
@@ -1311,7 +1311,7 @@
 		return f
 
 	case OCOMPLIT:
-		ptrlit := n.Right != nil && n.Right.Implicit != 0 && n.Right.Type != nil && Isptr[n.Right.Type.Etype] != 0
+		ptrlit := n.Right != nil && n.Right.Implicit != 0 && n.Right.Type != nil && Isptr[n.Right.Type.Etype]
 		if fmtmode == FErr {
 			if n.Right != nil && n.Right.Type != nil && n.Implicit == 0 {
 				if ptrlit {
diff --git a/src/cmd/internal/gc/gen.go b/src/cmd/internal/gc/gen.go
index 079158a..e8ca4d7 100644
--- a/src/cmd/internal/gc/gen.go
+++ b/src/cmd/internal/gc/gen.go
@@ -452,7 +452,7 @@
 	}
 
 	if n.Op == OSLICEARR || n.Op == OSLICE3ARR {
-		if Isptr[n.Left.Type.Etype] == 0 {
+		if !Isptr[n.Left.Type.Etype] {
 			Fatal("slicearr is supposed to work on pointer: %v\n", Nconv(n, obj.FmtSign))
 		}
 		Thearch.Cgen(&src, base)
diff --git a/src/cmd/internal/gc/go.go b/src/cmd/internal/gc/go.go
index a1debbd..4818cac 100644
--- a/src/cmd/internal/gc/go.go
+++ b/src/cmd/internal/gc/go.go
@@ -822,43 +822,33 @@
 
 var Simtype [NTYPE]uint8
 
-var Isptr [NTYPE]uint8
+var (
+	Isptr     [NTYPE]bool
+	isforw    [NTYPE]bool
+	Isint     [NTYPE]bool
+	Isfloat   [NTYPE]bool
+	Iscomplex [NTYPE]bool
+	Issigned  [NTYPE]bool
+	issimple  [NTYPE]bool
+)
 
-var isforw [NTYPE]uint8
+var (
+	okforeq    [NTYPE]bool
+	okforadd   [NTYPE]bool
+	okforand   [NTYPE]bool
+	okfornone  [NTYPE]bool
+	okforcmp   [NTYPE]bool
+	okforbool  [NTYPE]bool
+	okforcap   [NTYPE]bool
+	okforlen   [NTYPE]bool
+	okforarith [NTYPE]bool
+	okforconst [NTYPE]bool
+)
 
-var Isint [NTYPE]uint8
-
-var Isfloat [NTYPE]uint8
-
-var Iscomplex [NTYPE]uint8
-
-var Issigned [NTYPE]uint8
-
-var issimple [NTYPE]uint8
-
-var okforeq [NTYPE]uint8
-
-var okforadd [NTYPE]uint8
-
-var okforand [NTYPE]uint8
-
-var okfornone [NTYPE]uint8
-
-var okforcmp [NTYPE]uint8
-
-var okforbool [NTYPE]uint8
-
-var okforcap [NTYPE]uint8
-
-var okforlen [NTYPE]uint8
-
-var okforarith [NTYPE]uint8
-
-var okforconst [NTYPE]uint8
-
-var okfor [OEND][]byte
-
-var iscmp [OEND]uint8
+var (
+	okfor [OEND][]bool
+	iscmp [OEND]bool
+)
 
 var Minintval [NTYPE]*Mpint
 
diff --git a/src/cmd/internal/gc/go.y b/src/cmd/internal/gc/go.y
index 53aec54..0c86d0f 100644
--- a/src/cmd/internal/gc/go.y
+++ b/src/cmd/internal/gc/go.y
@@ -2118,7 +2118,7 @@
 			$$.Val = $3;
 		} else {
 			s = $2.Sym;
-			if s == nil && Isptr[$2.Etype] != 0 {
+			if s == nil && Isptr[$2.Etype] {
 				s = $2.Type.Sym;
 			}
 			p = importpkg;
diff --git a/src/cmd/internal/gc/inl.go b/src/cmd/internal/gc/inl.go
index 57a0ab6..f77bc48 100644
--- a/src/cmd/internal/gc/inl.go
+++ b/src/cmd/internal/gc/inl.go
@@ -50,7 +50,7 @@
 		// method
 		rcvr := getthisx(fn.Type).Type.Type
 
-		if Isptr[rcvr.Etype] != 0 {
+		if Isptr[rcvr.Etype] {
 			rcvr = rcvr.Type
 		}
 		if rcvr.Sym == nil {
diff --git a/src/cmd/internal/gc/pgen.go b/src/cmd/internal/gc/pgen.go
index b3045a0..1f3fa01 100644
--- a/src/cmd/internal/gc/pgen.go
+++ b/src/cmd/internal/gc/pgen.go
@@ -337,7 +337,7 @@
 	}
 
 	// Ideally we wouldn't see any integer types here, but we do.
-	if n.Type == nil || (Isptr[n.Type.Etype] == 0 && Isint[n.Type.Etype] == 0 && n.Type.Etype != TUNSAFEPTR) {
+	if n.Type == nil || (!Isptr[n.Type.Etype] && !Isint[n.Type.Etype] && n.Type.Etype != TUNSAFEPTR) {
 		Dump("checknil", n)
 		Fatal("bad checknil")
 	}
diff --git a/src/cmd/internal/gc/range.go b/src/cmd/internal/gc/range.go
index 616c859..5cc05ea 100644
--- a/src/cmd/internal/gc/range.go
+++ b/src/cmd/internal/gc/range.go
@@ -41,7 +41,7 @@
 		}
 	}
 
-	if Isptr[t.Etype] != 0 && Isfixedarray(t.Type) {
+	if Isptr[t.Etype] && Isfixedarray(t.Type) {
 		t = t.Type
 	}
 	n.Type = t
diff --git a/src/cmd/internal/gc/reflect.go b/src/cmd/internal/gc/reflect.go
index 6059e35..732dd36 100644
--- a/src/cmd/internal/gc/reflect.go
+++ b/src/cmd/internal/gc/reflect.go
@@ -358,10 +358,10 @@
 		// method does not apply.
 		this = getthisx(f.Type).Type.Type
 
-		if Isptr[this.Etype] != 0 && this.Type == t {
+		if Isptr[this.Etype] && this.Type == t {
 			continue
 		}
-		if Isptr[this.Etype] != 0 && Isptr[t.Etype] == 0 && f.Embedded != 2 && !isifacemethod(f.Type) {
+		if Isptr[this.Etype] && !Isptr[t.Etype] && f.Embedded != 2 && !isifacemethod(f.Type) {
 			continue
 		}
 
@@ -693,7 +693,7 @@
 	}
 
 	var sptr *Sym
-	if t.Sym != nil && Isptr[t.Etype] == 0 {
+	if t.Sym != nil && !Isptr[t.Etype] {
 		sptr = dtypesym(Ptrto(t))
 	} else {
 		sptr = weaktypesym(Ptrto(t))
@@ -868,7 +868,7 @@
 }
 
 func typenamesym(t *Type) *Sym {
-	if t == nil || (Isptr[t.Etype] != 0 && t.Type == nil) || isideal(t) {
+	if t == nil || (Isptr[t.Etype] && t.Type == nil) || isideal(t) {
 		Fatal("typename %v", Tconv(t, 0))
 	}
 	s := typesym(t)
@@ -987,7 +987,7 @@
 	// emit the type structures for int, float, etc.
 	tbase := t
 
-	if Isptr[t.Etype] != 0 && t.Sym == nil && t.Type.Sym != nil {
+	if Isptr[t.Etype] && t.Sym == nil && t.Type.Sym != nil {
 		tbase = t.Type
 	}
 	dupok := 0
@@ -1003,7 +1003,7 @@
 	if tbase.Sym != nil && tbase.Local == 0 {
 		return s
 	}
-	if isforw[tbase.Etype] != 0 {
+	if isforw[tbase.Etype] {
 		return s
 	}
 
diff --git a/src/cmd/internal/gc/sinit.go b/src/cmd/internal/gc/sinit.go
index 4cb2dd6..4da2426 100644
--- a/src/cmd/internal/gc/sinit.go
+++ b/src/cmd/internal/gc/sinit.go
@@ -1070,7 +1070,7 @@
 		Fatal("anylit: not lit")
 
 	case OPTRLIT:
-		if Isptr[t.Etype] == 0 {
+		if !Isptr[t.Etype] {
 			Fatal("anylit: not ptr")
 		}
 
diff --git a/src/cmd/internal/gc/subr.go b/src/cmd/internal/gc/subr.go
index c8eb1d6..541e2a4 100644
--- a/src/cmd/internal/gc/subr.go
+++ b/src/cmd/internal/gc/subr.go
@@ -714,7 +714,7 @@
 	n.Val.Ctype = CTINT
 	n.Type = t
 
-	if Isfloat[t.Etype] != 0 {
+	if Isfloat[t.Etype] {
 		Fatal("nodconst: bad type %v", Tconv(t, 0))
 	}
 }
@@ -818,7 +818,7 @@
 	if t == nil {
 		return false
 	}
-	if Isptr[t.Etype] == 0 {
+	if !Isptr[t.Etype] {
 		return false
 	}
 	t = t.Type
@@ -894,7 +894,7 @@
 	}
 
 	// strip away pointer if it's there
-	if Isptr[t.Etype] != 0 {
+	if Isptr[t.Etype] {
 		if t.Sym != nil {
 			return nil
 		}
@@ -910,7 +910,7 @@
 	}
 
 	// check types
-	if issimple[t.Etype] == 0 {
+	if !issimple[t.Etype] {
 		switch t.Etype {
 		default:
 			return nil
@@ -1259,14 +1259,14 @@
 
 	// 3. src and dst are unnamed pointer types
 	// and their base types have identical underlying types.
-	if Isptr[src.Etype] != 0 && Isptr[dst.Etype] != 0 && src.Sym == nil && dst.Sym == nil {
+	if Isptr[src.Etype] && Isptr[dst.Etype] && src.Sym == nil && dst.Sym == nil {
 		if Eqtype(src.Type.Orig, dst.Type.Orig) {
 			return OCONVNOP
 		}
 	}
 
 	// 4. src and dst are both integer or floating point types.
-	if (Isint[src.Etype] != 0 || Isfloat[src.Etype] != 0) && (Isint[dst.Etype] != 0 || Isfloat[dst.Etype] != 0) {
+	if (Isint[src.Etype] || Isfloat[src.Etype]) && (Isint[dst.Etype] || Isfloat[dst.Etype]) {
 		if Simtype[src.Etype] == Simtype[dst.Etype] {
 			return OCONVNOP
 		}
@@ -1274,7 +1274,7 @@
 	}
 
 	// 5. src and dst are both complex types.
-	if Iscomplex[src.Etype] != 0 && Iscomplex[dst.Etype] != 0 {
+	if Iscomplex[src.Etype] && Iscomplex[dst.Etype] {
 		if Simtype[src.Etype] == Simtype[dst.Etype] {
 			return OCONVNOP
 		}
@@ -1283,7 +1283,7 @@
 
 	// 6. src is an integer or has type []byte or []rune
 	// and dst is a string type.
-	if Isint[src.Etype] != 0 && dst.Etype == TSTRING {
+	if Isint[src.Etype] && dst.Etype == TSTRING {
 		return ORUNESTR
 	}
 
@@ -1308,12 +1308,12 @@
 	}
 
 	// 8. src is a pointer or uintptr and dst is unsafe.Pointer.
-	if (Isptr[src.Etype] != 0 || src.Etype == TUINTPTR) && dst.Etype == TUNSAFEPTR {
+	if (Isptr[src.Etype] || src.Etype == TUINTPTR) && dst.Etype == TUNSAFEPTR {
 		return OCONVNOP
 	}
 
 	// 9. src is unsafe.Pointer and dst is a pointer or uintptr.
-	if src.Etype == TUNSAFEPTR && (Isptr[dst.Etype] != 0 || dst.Etype == TUINTPTR) {
+	if src.Etype == TUNSAFEPTR && (Isptr[dst.Etype] || dst.Etype == TUINTPTR) {
 		return OCONVNOP
 	}
 
@@ -1719,7 +1719,7 @@
 	}
 
 	// common mistake: *struct and *interface.
-	if tl != nil && tr != nil && Isptr[tl.Etype] != 0 && Isptr[tr.Etype] != 0 {
+	if tl != nil && tr != nil && Isptr[tl.Etype] && Isptr[tr.Etype] {
 		if tl.Type.Etype == TSTRUCT && tr.Type.Etype == TINTER {
 			fmt_ += "\n\t(*struct vs *interface)"
 		} else if tl.Type.Etype == TINTER && tr.Type.Etype == TSTRUCT {
@@ -2038,7 +2038,7 @@
 // found with a given name
 func lookdot0(s *Sym, t *Type, save **Type, ignorecase int) int {
 	u := t
-	if Isptr[u.Etype] != 0 {
+	if Isptr[u.Etype] {
 		u = u.Type
 	}
 
@@ -2090,7 +2090,7 @@
 
 	c = 0
 	u = t
-	if Isptr[u.Etype] != 0 {
+	if Isptr[u.Etype] {
 		u = u.Type
 	}
 	if u.Etype != TSTRUCT && u.Etype != TINTER {
@@ -2153,7 +2153,7 @@
 
 			// rebuild elided dots
 			for c := d - 1; c >= 0; c-- {
-				if n.Left.Type != nil && Isptr[n.Left.Type.Etype] != 0 {
+				if n.Left.Type != nil && Isptr[n.Left.Type.Etype] {
 					n.Left.Implicit = 1
 				}
 				n.Left = Nod(ODOT, n.Left, newname(dotlist[c].field.Sym))
@@ -2187,7 +2187,7 @@
 
 func expand0(t *Type, followptr int) {
 	u := t
-	if Isptr[u.Etype] != 0 {
+	if Isptr[u.Etype] {
 		followptr = 1
 		u = u.Type
 	}
@@ -2240,7 +2240,7 @@
 	}
 
 	u := t
-	if Isptr[u.Etype] != 0 {
+	if Isptr[u.Etype] {
 		followptr = 1
 		u = u.Type
 	}
@@ -2442,7 +2442,7 @@
 	methodrcvr := getthisx(method.Type).Type.Type
 
 	// generate nil pointer check for better error
-	if Isptr[rcvr.Etype] != 0 && rcvr.Type == methodrcvr {
+	if Isptr[rcvr.Etype] && rcvr.Type == methodrcvr {
 		// generating wrapper from *T to T.
 		n := Nod(OIF, nil, nil)
 
@@ -2469,10 +2469,10 @@
 	dot := adddot(Nod(OXDOT, this.Left, newname(method.Sym)))
 
 	// generate call
-	if flag_race == 0 && Isptr[rcvr.Etype] != 0 && Isptr[methodrcvr.Etype] != 0 && method.Embedded != 0 && !isifacemethod(method.Type) {
+	if flag_race == 0 && Isptr[rcvr.Etype] && Isptr[methodrcvr.Etype] && method.Embedded != 0 && !isifacemethod(method.Type) {
 		// generate tail call: adjust pointer receiver and jump to embedded method.
 		dot = dot.Left // skip final .M
-		if Isptr[dotlist[0].field.Type.Etype] == 0 {
+		if !Isptr[dotlist[0].field.Type.Etype] {
 			dot = Nod(OADDR, dot, nil)
 		}
 		as := Nod(OAS, this.Left, Nod(OCONVNOP, dot, nil))
@@ -2503,7 +2503,7 @@
 	Curfn = fn
 
 	// wrappers where T is anonymous (struct or interface) can be duplicated.
-	if rcvr.Etype == TSTRUCT || rcvr.Etype == TINTER || Isptr[rcvr.Etype] != 0 && rcvr.Type.Etype == TSTRUCT {
+	if rcvr.Etype == TSTRUCT || rcvr.Etype == TINTER || Isptr[rcvr.Etype] && rcvr.Type.Etype == TSTRUCT {
 		fn.Dupok = 1
 	}
 	typecheck(&fn, Etop)
@@ -3015,7 +3015,7 @@
 
 		if c == 1 {
 			for i = 0; i < d; i++ {
-				if Isptr[dotlist[i].field.Type.Etype] != 0 {
+				if Isptr[dotlist[i].field.Type.Etype] {
 					*followptr = 1
 					break
 				}
@@ -3093,7 +3093,7 @@
 		// the method does not exist for value types.
 		rcvr = getthisx(tm.Type).Type.Type
 
-		if Isptr[rcvr.Etype] != 0 && Isptr[t0.Etype] == 0 && followptr == 0 && !isifacemethod(tm.Type) {
+		if Isptr[rcvr.Etype] && !Isptr[t0.Etype] && followptr == 0 && !isifacemethod(tm.Type) {
 			if false && Debug['r'] != 0 {
 				Yyerror("interface pointer mismatch")
 			}
@@ -3284,7 +3284,7 @@
 	if n == nil || n.Op != OLITERAL || n.Type == nil {
 		return -1
 	}
-	if Isint[n.Type.Etype] == 0 {
+	if !Isint[n.Type.Etype] {
 		return -1
 	}
 
@@ -3297,7 +3297,7 @@
 		b = b << 1
 	}
 
-	if Issigned[n.Type.Etype] == 0 {
+	if !Issigned[n.Type.Etype] {
 		return -1
 	}
 
diff --git a/src/cmd/internal/gc/swt.go b/src/cmd/internal/gc/swt.go
index 64ab47e..cf40ffc 100644
--- a/src/cmd/internal/gc/swt.go
+++ b/src/cmd/internal/gc/swt.go
@@ -87,7 +87,7 @@
 		if t != nil {
 			var badtype *Type
 			switch {
-			case okforeq[t.Etype] == 0:
+			case !okforeq[t.Etype]:
 				Yyerror("cannot switch on %v", Nconv(n.Ntest, obj.FmtLong))
 			case t.Etype == TARRAY && !Isfixedarray(t):
 				nilonly = "slice"
@@ -255,7 +255,7 @@
 	// handle the cases in order
 	for len(cc) > 0 {
 		// deal with expressions one at a time
-		if okforcmp[t.Etype] == 0 || cc[0].typ != caseKindExprConst {
+		if !okforcmp[t.Etype] || cc[0].typ != caseKindExprConst {
 			a := s.walkCases(cc[:1])
 			cas = list(cas, a)
 			cc = cc[1:]
diff --git a/src/cmd/internal/gc/typecheck.go b/src/cmd/internal/gc/typecheck.go
index cb0111e..36909854 100644
--- a/src/cmd/internal/gc/typecheck.go
+++ b/src/cmd/internal/gc/typecheck.go
@@ -405,7 +405,7 @@
 				v = toint(l.Val)
 
 			default:
-				if l.Type != nil && Isint[l.Type.Etype] != 0 && l.Op != OLITERAL {
+				if l.Type != nil && Isint[l.Type.Etype] && l.Op != OLITERAL {
 					Yyerror("non-constant array bound %v", Nconv(l, 0))
 				} else {
 					Yyerror("invalid array bound %v", Nconv(l, 0))
@@ -510,7 +510,7 @@
 			goto ret
 		}
 
-		if Isptr[t.Etype] == 0 {
+		if !Isptr[t.Etype] {
 			if top&(Erv|Etop) != 0 {
 				Yyerror("invalid indirect of %v", Nconv(n.Left, obj.FmtLong))
 				goto error
@@ -576,7 +576,7 @@
 		if t == nil {
 			goto error
 		}
-		if okfor[n.Op][t.Etype] == 0 {
+		if !okfor[n.Op][t.Etype] {
 			Yyerror("invalid operation: %v %v", Oconv(int(n.Op), 0), Tconv(t, 0))
 			goto error
 		}
@@ -678,7 +678,7 @@
 			goto ret
 		}
 
-		if Isptr[t.Etype] != 0 && t.Type.Etype != TINTER {
+		if Isptr[t.Etype] && t.Type.Etype != TINTER {
 			t = t.Type
 			if t == nil {
 				goto error
@@ -791,7 +791,7 @@
 				}
 			}
 
-			if n.Right.Type != nil && Isint[n.Right.Type.Etype] == 0 {
+			if n.Right.Type != nil && !Isint[n.Right.Type.Etype] {
 				Yyerror("non-integer %s index %v", why, Nconv(n.Right, 0))
 				break
 			}
@@ -905,7 +905,7 @@
 		if Istype(t, TSTRING) {
 			n.Type = t
 			n.Op = OSLICESTR
-		} else if Isptr[t.Etype] != 0 && Isfixedarray(t.Type) {
+		} else if Isptr[t.Etype] && Isfixedarray(t.Type) {
 			tp = t.Type
 			n.Type = typ(TARRAY)
 			n.Type.Type = tp.Type
@@ -965,7 +965,7 @@
 			goto error
 		}
 
-		if Isptr[t.Etype] != 0 && Isfixedarray(t.Type) {
+		if Isptr[t.Etype] && Isfixedarray(t.Type) {
 			tp = t.Type
 			n.Type = typ(TARRAY)
 			n.Type.Type = tp.Type
@@ -1136,18 +1136,18 @@
 		}
 		switch n.Op {
 		case OCAP:
-			if okforcap[t.Etype] == 0 {
+			if !okforcap[t.Etype] {
 				goto badcall1
 			}
 
 		case OLEN:
-			if okforlen[t.Etype] == 0 {
+			if !okforlen[t.Etype] {
 				goto badcall1
 			}
 
 		case OREAL,
 			OIMAG:
-			if Iscomplex[t.Etype] == 0 {
+			if !Iscomplex[t.Etype] {
 				goto badcall1
 			}
 			if Isconst(l, CTCPLX) {
@@ -1808,13 +1808,13 @@
 		defaultlit(&r, Types[TUINT])
 		n.Right = r
 		t := r.Type
-		if Isint[t.Etype] == 0 || Issigned[t.Etype] != 0 {
+		if !Isint[t.Etype] || Issigned[t.Etype] {
 			Yyerror("invalid operation: %v (shift count type %v, must be unsigned integer)", Nconv(n, 0), Tconv(r.Type, 0))
 			goto error
 		}
 
 		t = l.Type
-		if t != nil && t.Etype != TIDEAL && Isint[t.Etype] == 0 {
+		if t != nil && t.Etype != TIDEAL && !Isint[t.Etype] {
 			Yyerror("invalid operation: %v (shift of type %v)", Nconv(n, 0), Tconv(t, 0))
 			goto error
 		}
@@ -1843,7 +1843,7 @@
 		et = TINT
 	}
 	aop = 0
-	if iscmp[n.Op] != 0 && t.Etype != TIDEAL && !Eqtype(l.Type, r.Type) {
+	if iscmp[n.Op] && t.Etype != TIDEAL && !Eqtype(l.Type, r.Type) {
 		// comparison is okay as long as one side is
 		// assignable to the other.  convert so they have
 		// the same type.
@@ -1909,7 +1909,7 @@
 		}
 	}
 
-	if okfor[op][et] == 0 {
+	if !okfor[op][et] {
 		Yyerror("invalid operation: %v (operator %v not defined on %s)", Nconv(n, 0), Oconv(int(op), 0), typekind(t))
 		goto error
 	}
@@ -1942,7 +1942,7 @@
 	}
 
 	t = l.Type
-	if iscmp[n.Op] != 0 {
+	if iscmp[n.Op] {
 		evconst(n)
 		t = idealbool
 		if n.Op != OLITERAL {
@@ -1965,7 +1965,7 @@
 	}
 
 	if et == TSTRING {
-		if iscmp[n.Op] != 0 {
+		if iscmp[n.Op] {
 			n.Etype = n.Op
 			n.Op = OCMPSTR
 		} else if n.Op == OADD {
@@ -2123,7 +2123,7 @@
 	if t == nil {
 		return -1
 	}
-	if Isint[t.Etype] == 0 {
+	if !Isint[t.Etype] {
 		Yyerror("invalid slice index %v (type %v)", Nconv(r, 0), Tconv(t, 0))
 		return -1
 	}
@@ -2215,7 +2215,7 @@
 	n := *nn
 
 	t := n.Type
-	if t == nil || Isptr[t.Etype] == 0 {
+	if t == nil || !Isptr[t.Etype] {
 		return
 	}
 	t = t.Type
@@ -2293,7 +2293,7 @@
 		if r != nil {
 			if errnode != nil {
 				Yyerror("ambiguous selector %v", Nconv(errnode, 0))
-			} else if Isptr[t.Etype] != 0 {
+			} else if Isptr[t.Etype] {
 				Yyerror("ambiguous selector (%v).%v", Tconv(t, 0), Sconv(s, 0))
 			} else {
 				Yyerror("ambiguous selector %v.%v", Tconv(t, 0), Sconv(s, 0))
@@ -2338,7 +2338,7 @@
 	}
 
 	// disallow T.m if m requires *T receiver
-	if Isptr[getthisx(f2.Type).Type.Type.Etype] != 0 && Isptr[t.Etype] == 0 && f2.Embedded != 2 && !isifacemethod(f2.Type) {
+	if Isptr[getthisx(f2.Type).Type.Type.Etype] && !Isptr[t.Etype] && f2.Embedded != 2 && !isifacemethod(f2.Type) {
 		Yyerror("invalid method expression %v (needs pointer receiver: (*%v).%v)", Nconv(n, 0), Tconv(t, 0), Sconv(f2.Sym, obj.FmtShort))
 		return false
 	}
@@ -2387,7 +2387,7 @@
 		n.Type = f1.Type
 		n.Paramfld = f1
 		if t.Etype == TINTER {
-			if Isptr[n.Left.Type.Etype] != 0 {
+			if Isptr[n.Left.Type.Etype] {
 				n.Left = Nod(OIND, n.Left, nil) // implicitstar
 				n.Left.Implicit = 1
 				typecheck(&n.Left, Erv)
@@ -2435,7 +2435,7 @@
 			ll = ll.Left
 		}
 		if ll.Implicit != 0 {
-			if Isptr[ll.Type.Etype] != 0 && ll.Type.Sym != nil && ll.Type.Sym.Def != nil && ll.Type.Sym.Def.Op == OTYPE {
+			if Isptr[ll.Type.Etype] && ll.Type.Sym != nil && ll.Type.Sym.Def != nil && ll.Type.Sym.Def.Op == OTYPE {
 				// It is invalid to automatically dereference a named pointer type when selecting a method.
 				// Make n->left == ll to clarify error message.
 				n.Left = ll
@@ -2876,7 +2876,7 @@
 	nerr = nerrors
 	n.Type = t
 
-	if Isptr[t.Etype] != 0 {
+	if Isptr[t.Etype] {
 		// For better or worse, we don't allow pointers as the composite literal type,
 		// except when using the &T syntax, which sets implicit on the OIND.
 		if n.Right.Implicit == 0 {
@@ -3085,7 +3085,7 @@
 	}
 
 	n.Orig = norig
-	if Isptr[n.Type.Etype] != 0 {
+	if Isptr[n.Type.Etype] {
 		n = Nod(OPTRLIT, n, nil)
 		n.Typecheck = 1
 		n.Type = n.Left.Type
@@ -3538,7 +3538,7 @@
 
 	if embedlineno != 0 {
 		lineno = int32(embedlineno)
-		if Isptr[t.Etype] != 0 {
+		if Isptr[t.Etype] {
 			Yyerror("embedded type cannot be a pointer")
 		}
 	}
@@ -3705,7 +3705,7 @@
 
 		t := n.Type
 		if t != nil {
-			if okforconst[t.Etype] == 0 {
+			if !okforconst[t.Etype] {
 				Yyerror("invalid constant type %v", Tconv(t, 0))
 				goto ret
 			}
@@ -3826,7 +3826,7 @@
 		}
 	}
 
-	if Isint[n.Type.Etype] == 0 && n.Type.Etype != TIDEAL {
+	if !Isint[n.Type.Etype] && n.Type.Etype != TIDEAL {
 		Yyerror("non-integer %s argument in make(%v) - %v", arg, Tconv(t, 0), Tconv(n.Type, 0))
 		return -1
 	}
diff --git a/src/cmd/internal/gc/walk.go b/src/cmd/internal/gc/walk.go
index 4667494..cc09b4d 100644
--- a/src/cmd/internal/gc/walk.go
+++ b/src/cmd/internal/gc/walk.go
@@ -479,7 +479,7 @@
 		// delayed until now to preserve side effects.
 		t := n.Left.Type
 
-		if Isptr[t.Etype] != 0 {
+		if Isptr[t.Etype] {
 			t = t.Type
 		}
 		if Isfixedarray(t) {
@@ -1032,7 +1032,7 @@
 	case OCONV,
 		OCONVNOP:
 		if Thearch.Thechar == '5' {
-			if Isfloat[n.Left.Type.Etype] != 0 {
+			if Isfloat[n.Left.Type.Etype] {
 				if n.Type.Etype == TINT64 {
 					n = mkcall("float64toint64", n.Type, init, conv(n.Left, Types[TFLOAT64]))
 					goto ret
@@ -1044,7 +1044,7 @@
 				}
 			}
 
-			if Isfloat[n.Type.Etype] != 0 {
+			if Isfloat[n.Type.Etype] {
 				if n.Left.Type.Etype == TINT64 {
 					n = mkcall("int64tofloat64", n.Type, init, conv(n.Left, Types[TINT64]))
 					goto ret
@@ -1084,7 +1084,7 @@
 		 */
 		et := int(n.Left.Type.Etype)
 
-		if Iscomplex[et] != 0 && n.Op == ODIV {
+		if Iscomplex[et] && n.Op == ODIV {
 			t := n.Type
 			n = mkcall("complex128div", Types[TCOMPLEX128], init, conv(n.Left, Types[TCOMPLEX128]), conv(n.Right, Types[TCOMPLEX128]))
 			n = conv(n, t)
@@ -1092,7 +1092,7 @@
 		}
 
 		// Nothing to do for float divisions.
-		if Isfloat[et] != 0 {
+		if Isfloat[et] {
 			goto ret
 		}
 
@@ -1142,7 +1142,7 @@
 			goto ret
 		}
 		t := n.Left.Type
-		if t != nil && Isptr[t.Etype] != 0 {
+		if t != nil && Isptr[t.Etype] {
 			t = t.Type
 		}
 		if Isfixedarray(t) {
@@ -2005,13 +2005,13 @@
 				on = syslook("printiface", 1)
 			}
 			argtype(on, n.Type) // any-1
-		} else if Isptr[et] != 0 || et == TCHAN || et == TMAP || et == TFUNC || et == TUNSAFEPTR {
+		} else if Isptr[et] || et == TCHAN || et == TMAP || et == TFUNC || et == TUNSAFEPTR {
 			on = syslook("printpointer", 1)
 			argtype(on, n.Type) // any-1
 		} else if Isslice(n.Type) {
 			on = syslook("printslice", 1)
 			argtype(on, n.Type) // any-1
-		} else if Isint[et] != 0 {
+		} else if Isint[et] {
 			if et == TUINT64 {
 				if (t.Sym.Pkg == Runtimepkg || compiling_runtime != 0) && t.Sym.Name == "hex" {
 					on = syslook("printhex", 0)
@@ -2021,9 +2021,9 @@
 			} else {
 				on = syslook("printint", 0)
 			}
-		} else if Isfloat[et] != 0 {
+		} else if Isfloat[et] {
 			on = syslook("printfloat", 0)
-		} else if Iscomplex[et] != 0 {
+		} else if Iscomplex[et] {
 			on = syslook("printcomplex", 0)
 		} else if et == TBOOL {
 			on = syslook("printbool", 0)
@@ -3515,7 +3515,7 @@
 		andor = OOROR
 	}
 
-	if t.Etype == TARRAY && t.Bound <= 4 && issimple[t.Type.Etype] != 0 {
+	if t.Etype == TARRAY && t.Bound <= 4 && issimple[t.Type.Etype] {
 		// Four or fewer elements of a basic type.
 		// Unroll comparisons.
 		var li *Node
@@ -3636,7 +3636,7 @@
 	l := n.Left
 
 	r := n.Right
-	if (n.Op != OOR && n.Op != OXOR) || (l.Op != OLSH && l.Op != ORSH) || (r.Op != OLSH && r.Op != ORSH) || n.Type == nil || Issigned[n.Type.Etype] != 0 || l.Op == r.Op {
+	if (n.Op != OOR && n.Op != OXOR) || (l.Op != OLSH && l.Op != ORSH) || (r.Op != OLSH && r.Op != ORSH) || n.Type == nil || Issigned[n.Type.Etype] || l.Op == r.Op {
 		return
 	}
 
@@ -3684,7 +3684,7 @@
  */
 func walkmul(np **Node, init **NodeList) {
 	n := *np
-	if Isint[n.Type.Etype] == 0 {
+	if !Isint[n.Type.Etype] {
 		return
 	}
 
@@ -3797,7 +3797,7 @@
 		var m Magic
 		m.W = w
 
-		if Issigned[nl.Type.Etype] != 0 {
+		if Issigned[nl.Type.Etype] {
 			m.Sd = Mpgetfix(nr.Val.U.Xval)
 			Smagic(&m)
 		} else {
@@ -3926,7 +3926,7 @@
 		}
 
 	default:
-		if Issigned[n.Type.Etype] != 0 {
+		if Issigned[n.Type.Etype] {
 			if n.Op == OMOD {
 				// signed modulo 2^pow is like ANDing
 				// with the last pow bits, but if nl < 0,
@@ -4023,11 +4023,11 @@
 
 // return 1 if integer n must be in range [0, max), 0 otherwise
 func bounded(n *Node, max int64) bool {
-	if n.Type == nil || Isint[n.Type.Etype] == 0 {
+	if n.Type == nil || !Isint[n.Type.Etype] {
 		return false
 	}
 
-	sign := int(Issigned[n.Type.Etype])
+	sign := Issigned[n.Type.Etype]
 	bits := int32(8 * n.Type.Width)
 
 	if Smallintconst(n) {
@@ -4049,7 +4049,7 @@
 		}
 
 	case OMOD:
-		if sign == 0 && Smallintconst(n.Right) {
+		if !sign && Smallintconst(n.Right) {
 			v := Mpgetfix(n.Right.Val.U.Xval)
 			if 0 <= v && v <= max {
 				return true
@@ -4057,7 +4057,7 @@
 		}
 
 	case ODIV:
-		if sign == 0 && Smallintconst(n.Right) {
+		if !sign && Smallintconst(n.Right) {
 			v := Mpgetfix(n.Right.Val.U.Xval)
 			for bits > 0 && v >= 2 {
 				bits--
@@ -4066,7 +4066,7 @@
 		}
 
 	case ORSH:
-		if sign == 0 && Smallintconst(n.Right) {
+		if !sign && Smallintconst(n.Right) {
 			v := Mpgetfix(n.Right.Val.U.Xval)
 			if v > int64(bits) {
 				return true
@@ -4075,7 +4075,7 @@
 		}
 	}
 
-	if sign == 0 && bits <= 62 && 1<<uint(bits) <= max {
+	if !sign && bits <= 62 && 1<<uint(bits) <= max {
 		return true
 	}
 
@@ -4110,7 +4110,7 @@
 	}
 	field.Lastfn = Curfn
 	field.Outer = n.Left.Type
-	if Isptr[field.Outer.Etype] != 0 {
+	if Isptr[field.Outer.Etype] {
 		field.Outer = field.Outer.Type
 	}
 	if field.Outer.Sym == nil {
diff --git a/src/cmd/internal/gc/y.go b/src/cmd/internal/gc/y.go
index b05fe8f..6a43c34 100644
--- a/src/cmd/internal/gc/y.go
+++ b/src/cmd/internal/gc/y.go
@@ -3394,7 +3394,7 @@
 				yyVAL.node.Val = yyDollar[3].val
 			} else {
 				s = yyDollar[2].typ.Sym
-				if s == nil && Isptr[yyDollar[2].typ.Etype] != 0 {
+				if s == nil && Isptr[yyDollar[2].typ.Etype] {
 					s = yyDollar[2].typ.Type.Sym
 				}
 				p = importpkg