[dev.regabi] cmd/compile: simplify fmtmap

The format map is going to keep growing as we add more use of
concrete node types. Stop that by reporting all Node implementations
as Node.

Also, there's little point to reporting uses of %v, %p, %T, nor to reporting
formatting of basic types like int and []byte. Remove those too.
(Vet takes care of mistakes involving basic types now.)

Passes buildall w/ toolstash -cmp.

Change-Id: Ia9fb39b401c29bf0c76ffebaa24836c70acd773f
Reviewed-on: https://go-review.googlesource.com/c/go/+/275781
Trust: Russ Cox <rsc@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

src/cmd/compile/fmt_test.go

@@ -125,6 +125,12 @@ func TestFormats(t *testing.T) {
 			typ := p.types[index]
 			format := typ + " " + in // e.g., "*Node %n"
 
+			// Do not bother reporting basic types, nor %v, %T, %p.
+			// Vet handles basic types, and those three formats apply to all types.
+			if !strings.Contains(typ, ".") || (in == "%v" || in == "%T" || in == "%p") {
+				return in
+			}
+
 			// check if format is known
 			out, known := knownFormats[format]
 
@@ -413,7 +419,17 @@ func nodeString(n ast.Node) string {
 
 // typeString returns a string representation of n.
 func typeString(typ types.Type) string {
-	return filepath.ToSlash(typ.String())
+	s := filepath.ToSlash(typ.String())
+
+	// Report all the concrete IR types as Node, to shorten fmtmap.
+	const ir = "cmd/compile/internal/ir."
+	if s == "*"+ir+"Name" || s == "*"+ir+"Func" || s == "*"+ir+"Decl" ||
+		s == ir+"Ntype" || s == ir+"Expr" || s == ir+"Stmt" ||
+		strings.HasPrefix(s, "*"+ir) && (strings.HasSuffix(s, "Expr") || strings.HasSuffix(s, "Stmt")) {
+		return "cmd/compile/internal/ir.Node"
+	}
+
+	return s
 }
 
 // stringLit returns the unquoted string value and true if

src/cmd/compile/fmtmap_test.go

@@ -21,31 +21,12 @@ package main_test
 // An empty new format means that the format should remain unchanged.
 var knownFormats = map[string]string{
 	"*bytes.Buffer %s":                             "",
-	"*cmd/compile/internal/gc.EscLocation %v":         "",
-	"*cmd/compile/internal/ir.Func %+v":               "",
-	"*cmd/compile/internal/ir.Func %L":                "",
-	"*cmd/compile/internal/ir.Func %v":                "",
-	"*cmd/compile/internal/ir.Name %#v":               "",
-	"*cmd/compile/internal/ir.Name %+v":               "",
-	"*cmd/compile/internal/ir.Name %L":                "",
-	"*cmd/compile/internal/ir.Name %v":                "",
-	"*cmd/compile/internal/ir.SliceExpr %v":           "",
 	"*cmd/compile/internal/ssa.Block %s":           "",
-	"*cmd/compile/internal/ssa.Block %v":              "",
 	"*cmd/compile/internal/ssa.Func %s":            "",
-	"*cmd/compile/internal/ssa.Func %v":               "",
 	"*cmd/compile/internal/ssa.Register %s":        "",
-	"*cmd/compile/internal/ssa.Register %v":           "",
-	"*cmd/compile/internal/ssa.SparseTreeNode %v":     "",
 	"*cmd/compile/internal/ssa.Value %s":           "",
-	"*cmd/compile/internal/ssa.Value %v":              "",
-	"*cmd/compile/internal/ssa.sparseTreeMapEntry %v": "",
-	"*cmd/compile/internal/types.Field %p":            "",
-	"*cmd/compile/internal/types.Field %v":            "",
 	"*cmd/compile/internal/types.Sym %+v":          "",
 	"*cmd/compile/internal/types.Sym %S":           "",
-	"*cmd/compile/internal/types.Sym %p":              "",
-	"*cmd/compile/internal/types.Sym %v":              "",
 	"*cmd/compile/internal/types.Type %#L":         "",
 	"*cmd/compile/internal/types.Type %#v":         "",
 	"*cmd/compile/internal/types.Type %+v":         "",
@@ -53,65 +34,29 @@ var knownFormats = map[string]string{
 	"*cmd/compile/internal/types.Type %0S":         "",
 	"*cmd/compile/internal/types.Type %L":          "",
 	"*cmd/compile/internal/types.Type %S":          "",
-	"*cmd/compile/internal/types.Type %p":             "",
 	"*cmd/compile/internal/types.Type %s":          "",
-	"*cmd/compile/internal/types.Type %v":             "",
-	"*cmd/internal/obj.Addr %v":                       "",
-	"*cmd/internal/obj.LSym %v":                       "",
 	"*math/big.Float %f":                           "",
 	"*math/big.Int %s":                             "",
-	"[16]byte %x":                                     "",
-	"[]*cmd/compile/internal/ir.Name %v":              "",
-	"[]*cmd/compile/internal/ssa.Block %v":            "",
-	"[]*cmd/compile/internal/ssa.Value %v":            "",
-	"[][]string %q":                                   "",
-	"[]byte %s":                                       "",
-	"[]byte %x":                                       "",
-	"[]cmd/compile/internal/ssa.Edge %v":              "",
-	"[]cmd/compile/internal/ssa.ID %v":                "",
-	"[]cmd/compile/internal/ssa.posetNode %v":         "",
-	"[]cmd/compile/internal/ssa.posetUndo %v":         "",
 	"[]cmd/compile/internal/syntax.token %s":       "",
-	"[]string %v":                                     "",
-	"[]uint32 %v":                                     "",
-	"bool %v":                                         "",
-	"byte %08b":                                       "",
-	"byte %c":                                         "",
-	"byte %q":                                         "",
-	"byte %v":                                         "",
 	"cmd/compile/internal/arm.shift %d":            "",
 	"cmd/compile/internal/gc.initKind %d":          "",
-	"cmd/compile/internal/gc.itag %v":                 "",
 	"cmd/compile/internal/ir.Class %d":             "",
-	"cmd/compile/internal/ir.Class %v":                "",
+	"cmd/compile/internal/ir.Node %#v":             "",
 	"cmd/compile/internal/ir.Node %+v":             "",
 	"cmd/compile/internal/ir.Node %L":              "",
 	"cmd/compile/internal/ir.Node %S":              "",
-	"cmd/compile/internal/ir.Node %p":                 "",
-	"cmd/compile/internal/ir.Node %v":                 "",
 	"cmd/compile/internal/ir.Nodes %#v":            "",
 	"cmd/compile/internal/ir.Nodes %+v":            "",
 	"cmd/compile/internal/ir.Nodes %.v":            "",
-	"cmd/compile/internal/ir.Nodes %v":                "",
-	"cmd/compile/internal/ir.Ntype %v":                "",
 	"cmd/compile/internal/ir.Op %#v":               "",
 	"cmd/compile/internal/ir.Op %+v":               "",
-	"cmd/compile/internal/ir.Op %v":                   "",
 	"cmd/compile/internal/ssa.BranchPrediction %d": "",
-	"cmd/compile/internal/ssa.Edge %v":                "",
 	"cmd/compile/internal/ssa.ID %d":               "",
-	"cmd/compile/internal/ssa.ID %v":                  "",
 	"cmd/compile/internal/ssa.LocalSlot %s":        "",
-	"cmd/compile/internal/ssa.LocalSlot %v":           "",
 	"cmd/compile/internal/ssa.Location %s":         "",
 	"cmd/compile/internal/ssa.Op %s":               "",
-	"cmd/compile/internal/ssa.Op %v":                  "",
-	"cmd/compile/internal/ssa.Sym %v":                 "",
 	"cmd/compile/internal/ssa.ValAndOff %s":        "",
-	"cmd/compile/internal/ssa.domain %v":              "",
 	"cmd/compile/internal/ssa.flagConstant %s":     "",
-	"cmd/compile/internal/ssa.posetNode %v":           "",
-	"cmd/compile/internal/ssa.posetTestOp %v":         "",
 	"cmd/compile/internal/ssa.rbrank %d":           "",
 	"cmd/compile/internal/ssa.regMask %d":          "",
 	"cmd/compile/internal/ssa.register %d":         "",
@@ -119,92 +64,15 @@ var knownFormats = map[string]string{
 	"cmd/compile/internal/syntax.Error %q":         "",
 	"cmd/compile/internal/syntax.Expr %#v":         "",
 	"cmd/compile/internal/syntax.LitKind %d":       "",
-	"cmd/compile/internal/syntax.Node %T":             "",
 	"cmd/compile/internal/syntax.Operator %s":      "",
 	"cmd/compile/internal/syntax.Pos %s":           "",
-	"cmd/compile/internal/syntax.Pos %v":              "",
 	"cmd/compile/internal/syntax.position %s":      "",
 	"cmd/compile/internal/syntax.token %q":         "",
 	"cmd/compile/internal/syntax.token %s":         "",
 	"cmd/compile/internal/types.Kind %d":           "",
 	"cmd/compile/internal/types.Kind %s":           "",
-	"cmd/compile/internal/types.Kind %v":              "",
-	"cmd/compile/internal/types.Object %v":            "",
-	"cmd/internal/obj.ABI %v":                         "",
-	"error %v":                                        "",
-	"float64 %.2f":                                    "",
-	"float64 %.3f":                                    "",
-	"float64 %g":                                      "",
-	"go/constant.Kind %v":                             "",
 	"go/constant.Value %#v":                        "",
-	"go/constant.Value %v":                            "",
-	"int %#x":                                         "",
-	"int %-12d":                                       "",
-	"int %-6d":                                        "",
-	"int %-8o":                                        "",
-	"int %02d":                                        "",
-	"int %6d":                                         "",
-	"int %c":                                          "",
-	"int %d":                                          "",
-	"int %v":                                          "",
-	"int %x":                                          "",
-	"int16 %d":                                        "",
-	"int16 %x":                                        "",
-	"int32 %#x":                                       "",
-	"int32 %d":                                        "",
-	"int32 %v":                                        "",
-	"int32 %x":                                        "",
-	"int64 %#x":                                       "",
-	"int64 %-10d":                                     "",
-	"int64 %.5d":                                      "",
-	"int64 %d":                                        "",
-	"int64 %v":                                        "",
-	"int64 %x":                                        "",
-	"int8 %d":                                         "",
-	"int8 %v":                                         "",
-	"int8 %x":                                         "",
-	"interface{} %#v":                                 "",
-	"interface{} %T":                                  "",
-	"interface{} %p":                                  "",
-	"interface{} %q":                                  "",
-	"interface{} %s":                                  "",
-	"interface{} %v":                                  "",
-	"map[cmd/compile/internal/ir.Node]*cmd/compile/internal/ssa.Value %v": "",
-	"map[cmd/compile/internal/ir.Node][]cmd/compile/internal/ir.Node %v":  "",
-	"map[cmd/compile/internal/ssa.ID]uint32 %v":                           "",
-	"map[int64]uint32 %v":  "",
 	"math/big.Accuracy %s":                         "",
 	"reflect.Type %s":                              "",
-	"reflect.Type %v":      "",
-	"rune %#U":             "",
-	"rune %c":              "",
-	"rune %q":              "",
-	"string %-*s":          "",
-	"string %-16s":         "",
-	"string %-6s":          "",
-	"string %q":            "",
-	"string %s":            "",
-	"string %v":            "",
 	"time.Duration %d":                             "",
-	"time.Duration %v":     "",
-	"uint %04x":            "",
-	"uint %5d":             "",
-	"uint %d":              "",
-	"uint %x":              "",
-	"uint16 %d":            "",
-	"uint16 %x":            "",
-	"uint32 %#U":           "",
-	"uint32 %#x":           "",
-	"uint32 %d":            "",
-	"uint32 %v":            "",
-	"uint32 %x":            "",
-	"uint64 %08x":          "",
-	"uint64 %b":            "",
-	"uint64 %d":            "",
-	"uint64 %x":            "",
-	"uint8 %#x":            "",
-	"uint8 %d":             "",
-	"uint8 %v":             "",
-	"uint8 %x":             "",
-	"uintptr %d":           "",
 }