libgo: update to Go1.10beta1

    
    Update the Go library to the 1.10beta1 release.
    
    Requires a few changes to the compiler for modifications to the map
    runtime code, and to handle some nowritebarrier cases in the runtime.
    
    Reviewed-on: https://go-review.googlesource.com/86455

gotools/:
	* Makefile.am (go_cmd_vet_files): New variable.
	(go_cmd_buildid_files, go_cmd_test2json_files): New variables.
	(s-zdefaultcc): Change from constants to functions.
	(noinst_PROGRAMS): Add vet, buildid, and test2json.
	(cgo$(EXEEXT)): Link against $(LIBGOTOOL).
	(vet$(EXEEXT)): New target.
	(buildid$(EXEEXT)): New target.
	(test2json$(EXEEXT)): New target.
	(install-exec-local): Install all $(noinst_PROGRAMS).
	(uninstall-local): Uninstasll all $(noinst_PROGRAMS).
	(check-go-tool): Depend on $(noinst_PROGRAMS).  Copy down
	objabi.go.
	(check-runtime): Depend on $(noinst_PROGRAMS).
	(check-cgo-test, check-carchive-test): Likewise.
	(check-vet): New target.
	(check): Depend on check-vet.  Look at cmd_vet-testlog.
	(.PHONY): Add check-vet.
	* Makefile.in: Rebuild.

From-SVN: r256365

1 files changed, 7 insertions, 8 deletions

diff --git a/libgo/go/regexp/exec.go b/libgo/go/regexp/exec.go
index f8fe7b5..84cb3e6 100644
--- a/libgo/go/regexp/exec.go
+++ b/libgo/go/regexp/exec.go
@@ -16,7 +16,7 @@ type queue struct {
 	dense  []entry
 }
 
-// A entry is an entry on a queue.
+// An entry is an entry on a queue.
 // It holds both the instruction pc and the actual thread.
 // Some queue entries are just place holders so that the machine
 // knows it has considered that pc. Such entries have t == nil.
@@ -338,15 +338,14 @@ func (m *machine) onepass(i input, pos, ncap int) bool {
 	if pos == 0 && syntax.EmptyOp(inst.Arg)&^flag == 0 &&
 		len(m.re.prefix) > 0 && i.canCheckPrefix() {
 		// Match requires literal prefix; fast search for it.
-		if i.hasPrefix(m.re) {
-			pos += len(m.re.prefix)
-			r, width = i.step(pos)
-			r1, width1 = i.step(pos + width)
-			flag = i.context(pos)
-			pc = int(m.re.prefixEnd)
-		} else {
+		if !i.hasPrefix(m.re) {
 			return m.matched
 		}
+		pos += len(m.re.prefix)
+		r, width = i.step(pos)
+		r1, width1 = i.step(pos + width)
+		flag = i.context(pos)
+		pc = int(m.re.prefixEnd)
 	}
 	for {
 		inst = m.op.Inst[pc]