libgo: update to Go 1.8 release candidate 1

    
    Compiler changes:
      * Change map assignment to use mapassign and assign value directly.
      * Change string iteration to use decoderune, faster for ASCII strings.
      * Change makeslice to take int, and use makeslice64 for larger values.
      * Add new noverflow field to hmap struct used for maps.
    
    Unresolved problems, to be fixed later:
      * Commented out test in go/types/sizes_test.go that doesn't compile.
      * Commented out reflect.TestStructOf test for padding after zero-sized field.
    
    Reviewed-on: https://go-review.googlesource.com/35231

gotools/:
	Updates for Go 1.8rc1.
	* Makefile.am (go_cmd_go_files): Add bug.go.
	(s-zdefaultcc): Write defaultPkgConfig.
	* Makefile.in: Rebuild.

From-SVN: r244456

1 files changed, 13 insertions, 9 deletions

diff --git a/libgo/go/testing/benchmark.go b/libgo/go/testing/benchmark.go
index 5d58b85..c033ce5 100644
--- a/libgo/go/testing/benchmark.go
+++ b/libgo/go/testing/benchmark.go
@@ -7,6 +7,7 @@ package testing
 import (
 	"flag"
 	"fmt"
+	"internal/race"
 	"os"
 	"runtime"
 	"sync"
@@ -14,8 +15,8 @@ import (
 	"time"
 )
 
-var matchBenchmarks = flag.String("test.bench", "", "regular expression per path component to select benchmarks to run")
-var benchTime = flag.Duration("test.benchtime", 1*time.Second, "approximate run time for each benchmark")
+var matchBenchmarks = flag.String("test.bench", "", "run only benchmarks matching `regexp`")
+var benchTime = flag.Duration("test.benchtime", 1*time.Second, "run each benchmark for duration `d`")
 var benchmarkMemory = flag.Bool("test.benchmem", false, "print memory allocations for benchmarks")
 
 // Global lock to ensure only one benchmark runs at a time.
@@ -56,7 +57,6 @@ type B struct {
 	missingBytes     bool // one of the subbenchmarks does not have bytes set.
 	timerOn          bool
 	showAllocResult  bool
-	hasSub           bool
 	result           BenchmarkResult
 	parallelism      int // RunParallel creates parallelism*GOMAXPROCS goroutines
 	// The initial states of memStats.Mallocs and memStats.TotalAlloc.
@@ -132,6 +132,7 @@ func (b *B) runN(n int) {
 	// Try to get a comparable environment for each run
 	// by clearing garbage from previous runs.
 	runtime.GC()
+	b.raceErrors = -race.Errors()
 	b.N = n
 	b.parallelism = 1
 	b.ResetTimer()
@@ -140,6 +141,10 @@ func (b *B) runN(n int) {
 	b.StopTimer()
 	b.previousN = n
 	b.previousDuration = b.duration
+	b.raceErrors += race.Errors()
+	if b.raceErrors > 0 {
+		b.Errorf("race detected during execution of benchmark")
+	}
 }
 
 func min(x, y int) int {
@@ -263,10 +268,9 @@ func (b *B) launch() {
 	for n := 1; !b.failed && b.duration < d && n < 1e9; {
 		last := n
 		// Predict required iterations.
-		if b.nsPerOp() == 0 {
-			n = 1e9
-		} else {
-			n = int(d.Nanoseconds() / b.nsPerOp())
+		n = int(d.Nanoseconds())
+		if nsop := b.nsPerOp(); nsop != 0 {
+			n /= int(nsop)
 		}
 		// Run more iterations than we think we'll need (1.2x).
 		// Don't grow too fast in case we had timing errors previously.
@@ -359,10 +363,10 @@ type benchContext struct {
 // An internal function but exported because it is cross-package; part of the implementation
 // of the "go test" command.
 func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark) {
-	runBenchmarksInternal(matchString, benchmarks)
+	runBenchmarks(matchString, benchmarks)
 }
 
-func runBenchmarksInternal(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark) bool {
+func runBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark) bool {
 	// If no flag was specified, don't run benchmarks.
 	if len(*matchBenchmarks) == 0 {
 		return true