[dev.regabi] cmd/compile: introduce cmd/compile/internal/base [generated]

Move Flag, Debug, Ctxt, Exit, and error messages to
new package cmd/compile/internal/base.

These are the core functionality that everything in gc uses
and which otherwise prevent splitting any other code
out of gc into different packages.

A minor milestone: the compiler source code
no longer contains the string "yy".

[git-generate]
cd src/cmd/compile/internal/gc
rf '
        mv atExit AtExit
        mv Ctxt atExitFuncs AtExit Exit base.go

        mv lineno Pos
        mv linestr FmtPos
        mv flusherrors FlushErrors
        mv yyerror Errorf
        mv yyerrorl ErrorfAt
        mv yyerrorv ErrorfVers
        mv noder.yyerrorpos noder.errorAt
        mv Warnl WarnfAt
        mv errorexit ErrorExit

        mv base.go debug.go flag.go print.go cmd/compile/internal/base
'

: # update comments
sed -i '' 's/yyerrorl/ErrorfAt/g; s/yyerror/Errorf/g' *.go

: # bootstrap.go is not built by default so invisible to rf
sed -i '' 's/Fatalf/base.Fatalf/' bootstrap.go
goimports -w bootstrap.go

: # update cmd/dist to add internal/base
cd ../../../dist
sed -i '' '/internal.amd64/a\
	"cmd/compile/internal/base",
' buildtool.go
gofmt -w buildtool.go

Change-Id: I59903c7084222d6eaee38823fd222159ba24a31a
Reviewed-on: https://go-review.googlesource.com/c/go/+/272250
Trust: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

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

@@ -5,6 +5,7 @@
 package gc
 
 import (
+	"cmd/compile/internal/base"
 	"cmd/compile/internal/types"
 	"cmd/internal/sys"
 	"unicode/utf8"
@@ -61,7 +62,7 @@ func typecheckrangeExpr(n *Node) {
 	toomany := false
 	switch t.Etype {
 	default:
-		yyerrorl(n.Pos, "cannot range over %L", n.Right)
+		base.ErrorfAt(n.Pos, "cannot range over %L", n.Right)
 		return
 
 	case TARRAY, TSLICE:
@@ -74,7 +75,7 @@ func typecheckrangeExpr(n *Node) {
 
 	case TCHAN:
 		if !t.ChanDir().CanRecv() {
-			yyerrorl(n.Pos, "invalid operation: range %v (receive from send-only type %v)", n.Right, n.Right.Type)
+			base.ErrorfAt(n.Pos, "invalid operation: range %v (receive from send-only type %v)", n.Right, n.Right.Type)
 			return
 		}
 
@@ -90,7 +91,7 @@ func typecheckrangeExpr(n *Node) {
 	}
 
 	if n.List.Len() > 2 || toomany {
-		yyerrorl(n.Pos, "too many variables in range")
+		base.ErrorfAt(n.Pos, "too many variables in range")
 	}
 
 	var v1, v2 *Node
@@ -117,7 +118,7 @@ func typecheckrangeExpr(n *Node) {
 			v1.Type = t1
 		} else if v1.Type != nil {
 			if op, why := assignop(t1, v1.Type); op == OXXX {
-				yyerrorl(n.Pos, "cannot assign type %v to %L in range%s", t1, v1, why)
+				base.ErrorfAt(n.Pos, "cannot assign type %v to %L in range%s", t1, v1, why)
 			}
 		}
 		checkassign(n, v1)
@@ -128,7 +129,7 @@ func typecheckrangeExpr(n *Node) {
 			v2.Type = t2
 		} else if v2.Type != nil {
 			if op, why := assignop(t2, v2.Type); op == OXXX {
-				yyerrorl(n.Pos, "cannot assign type %v to %L in range%s", t2, v2, why)
+				base.ErrorfAt(n.Pos, "cannot assign type %v to %L in range%s", t2, v2, why)
 			}
 		}
 		checkassign(n, v2)
@@ -160,7 +161,7 @@ func walkrange(n *Node) *Node {
 		m := n.Right
 		lno := setlineno(m)
 		n = mapClear(m)
-		lineno = lno
+		base.Pos = lno
 		return n
 	}
 
@@ -196,7 +197,7 @@ func walkrange(n *Node) *Node {
 	}
 
 	if v1 == nil && v2 != nil {
-		Fatalf("walkrange: v2 != nil while v1 == nil")
+		base.Fatalf("walkrange: v2 != nil while v1 == nil")
 	}
 
 	// n.List has no meaning anymore, clear it
@@ -211,11 +212,11 @@ func walkrange(n *Node) *Node {
 	var init []*Node
 	switch t.Etype {
 	default:
-		Fatalf("walkrange")
+		base.Fatalf("walkrange")
 
 	case TARRAY, TSLICE:
 		if arrayClear(n, v1, v2, a) {
-			lineno = lno
+			base.Pos = lno
 			return n
 		}
 
@@ -454,7 +455,7 @@ func walkrange(n *Node) *Node {
 
 	n = walkstmt(n)
 
-	lineno = lno
+	base.Pos = lno
 	return n
 }
 
@@ -466,7 +467,7 @@ func walkrange(n *Node) *Node {
 //
 // where == for keys of map m is reflexive.
 func isMapClear(n *Node) bool {
-	if Flag.N != 0 || instrumenting {
+	if base.Flag.N != 0 || instrumenting {
 		return false
 	}
 
@@ -533,7 +534,7 @@ func mapClear(m *Node) *Node {
 //
 // Parameters are as in walkrange: "for v1, v2 = range a".
 func arrayClear(n, v1, v2, a *Node) bool {
-	if Flag.N != 0 || instrumenting {
+	if base.Flag.N != 0 || instrumenting {
 		return false
 	}