libgo: update to Go1.18beta2

gotools/
	* Makefile.am (go_cmd_cgo_files): Add ast_go118.go
	(check-go-tool): Copy golang.org/x/tools directories.
	* Makefile.in: Regenerate.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/384695

4 files changed, 15 insertions, 14 deletions

diff --git a/libgo/go/strconv/fp_test.go b/libgo/go/strconv/fp_test.go
index 39dd9c4..fd73958 100644
--- a/libgo/go/strconv/fp_test.go
+++ b/libgo/go/strconv/fp_test.go
@@ -28,15 +28,14 @@ func pow2(i int) float64 {
 // Wrapper around strconv.ParseFloat(x, 64).  Handles dddddp+ddd (binary exponent)
 // itself, passes the rest on to strconv.ParseFloat.
 func myatof64(s string) (f float64, ok bool) {
-	a := strings.SplitN(s, "p", 2)
-	if len(a) == 2 {
-		n, err := strconv.ParseInt(a[0], 10, 64)
+	if mant, exp, ok := strings.Cut(s, "p"); ok {
+		n, err := strconv.ParseInt(mant, 10, 64)
 		if err != nil {
 			return 0, false
 		}
-		e, err1 := strconv.Atoi(a[1])
+		e, err1 := strconv.Atoi(exp)
 		if err1 != nil {
-			println("bad e", a[1])
+			println("bad e", exp)
 			return 0, false
 		}
 		v := float64(n)
@@ -72,16 +71,15 @@ func myatof64(s string) (f float64, ok bool) {
 // Wrapper around strconv.ParseFloat(x, 32).  Handles dddddp+ddd (binary exponent)
 // itself, passes the rest on to strconv.ParseFloat.
 func myatof32(s string) (f float32, ok bool) {
-	a := strings.SplitN(s, "p", 2)
-	if len(a) == 2 {
-		n, err := strconv.Atoi(a[0])
+	if mant, exp, ok := strings.Cut(s, "p"); ok {
+		n, err := strconv.Atoi(mant)
 		if err != nil {
-			println("bad n", a[0])
+			println("bad n", mant)
 			return 0, false
 		}
-		e, err1 := strconv.Atoi(a[1])
+		e, err1 := strconv.Atoi(exp)
 		if err1 != nil {
-			println("bad p", a[1])
+			println("bad p", exp)
 			return 0, false
 		}
 		return float32(float64(n) * pow2(e)), true
diff --git a/libgo/go/strconv/ftoaryu.go b/libgo/go/strconv/ftoaryu.go
index 1c61288..f2e74be 100644
--- a/libgo/go/strconv/ftoaryu.go
+++ b/libgo/go/strconv/ftoaryu.go
@@ -291,7 +291,7 @@ func ryuFtoaShortest(d *decimalSlice, mant uint64, exp int, flt *floatInfo) {
 	// Is it allowed to use 'du' as a result?
 	// It is always allowed when it is truncated, but also
 	// if it is exact and the original binary mantissa is even
-	// When disallowed, we can substract 1.
+	// When disallowed, we can subtract 1.
 	uok := !du0 || fracu > 0
 	if du0 && fracu == 0 {
 		uok = mant&1 == 0
diff --git a/libgo/go/strconv/quote.go b/libgo/go/strconv/quote.go
index b3bbb16..d2814b9 100644
--- a/libgo/go/strconv/quote.go
+++ b/libgo/go/strconv/quote.go
@@ -103,7 +103,7 @@ func appendEscapedRune(buf []byte, r rune, quote byte, ASCIIonly, graphicOnly bo
 			buf = append(buf, `\x`...)
 			buf = append(buf, lowerhex[byte(r)>>4])
 			buf = append(buf, lowerhex[byte(r)&0xF])
-		case r > utf8.MaxRune:
+		case !utf8.ValidRune(r):
 			r = 0xFFFD
 			fallthrough
 		case r < 0x10000:
@@ -322,7 +322,7 @@ func UnquoteChar(s string, quote byte) (value rune, multibyte bool, tail string,
 			value = v
 			break
 		}
-		if v > utf8.MaxRune {
+		if !utf8.ValidRune(v) {
 			err = ErrSyntax
 			return
 		}
diff --git a/libgo/go/strconv/quote_test.go b/libgo/go/strconv/quote_test.go
index 4750be2..81fc8f7 100644
--- a/libgo/go/strconv/quote_test.go
+++ b/libgo/go/strconv/quote_test.go
@@ -131,6 +131,7 @@ var quoterunetests = []quoteRuneTest{
 	{'\\', `'\\'`, `'\\'`, `'\\'`},
 	{0xFF, `'ÿ'`, `'\u00ff'`, `'ÿ'`},
 	{0x263a, `'☺'`, `'\u263a'`, `'☺'`},
+	{0xdead, `'�'`, `'\ufffd'`, `'�'`},
 	{0xfffd, `'�'`, `'\ufffd'`, `'�'`},
 	{0x0010ffff, `'\U0010ffff'`, `'\U0010ffff'`, `'\U0010ffff'`},
 	{0x0010ffff + 1, `'�'`, `'\ufffd'`, `'�'`},
@@ -305,6 +306,8 @@ var misquoted = []string{
 	"\"\n\"",
 	"\"\\n\n\"",
 	"'\n'",
+	`"\udead"`,
+	`"\ud83d\ude4f"`,
 }
 
 func TestUnquote(t *testing.T) {