Move tools to a tools/src directory

Allows bash scripts to share the same name as the directory.

Add fix-tests bash script.

Change-Id: Iaf1943d50ec1fd3f382a2c7823fb7cdd13b1d9a2
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/47766
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>

tools/src/run-parallel/main.go

@@ -0,0 +1,133 @@
+// Copyright 2021 The Tint Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// run-parallel is a tool to run an executable with the provided templated
+// arguments across all the hardware threads.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"os/exec"
+	"runtime"
+	"strings"
+	"sync"
+)
+
+func main() {
+	if err := run(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+
+func showUsage() {
+	fmt.Println(`
+run-parallel is a tool to run an executable with the provided templated
+arguments across all the hardware threads.
+
+Usage:
+  run-parallel <executable> [arguments...] -- [per-instance-value...]
+
+  executable         - the path to the executable to run.
+  arguments          - a list of arguments to pass to the executable.
+                       Any occurrance of $ will be substituted with the
+                       per-instance-value for the given invocation.
+  per-instance-value - a list of values. The executable will be invoked for each
+                       value in this list.`)
+	os.Exit(1)
+}
+
+func run() error {
+	onlyPrintFailures := flag.Bool("only-print-failures", false, "Omit output for processes that did not fail")
+	flag.Parse()
+
+	args := flag.Args()
+	if len(args) < 2 {
+		showUsage()
+	}
+	exe := args[0]
+	args = args[1:]
+
+	var perInstanceValues []string
+	for i, arg := range args {
+		if arg == "--" {
+			perInstanceValues = args[i+1:]
+			args = args[:i]
+			break
+		}
+	}
+	if perInstanceValues == nil {
+		showUsage()
+	}
+
+	taskIndices := make(chan int, 64)
+	type result struct {
+		msg    string
+		failed bool
+	}
+	results := make([]result, len(perInstanceValues))
+
+	numCPU := runtime.NumCPU()
+	wg := sync.WaitGroup{}
+	wg.Add(numCPU)
+	for i := 0; i < numCPU; i++ {
+		go func() {
+			defer wg.Done()
+			for idx := range taskIndices {
+				taskArgs := make([]string, len(args))
+				for i, arg := range args {
+					taskArgs[i] = strings.ReplaceAll(arg, "$", perInstanceValues[idx])
+				}
+				success, out := invoke(exe, taskArgs)
+				if !success || !*onlyPrintFailures {
+					results[idx] = result{out, !success}
+				}
+			}
+		}()
+	}
+
+	for i := range perInstanceValues {
+		taskIndices <- i
+	}
+	close(taskIndices)
+
+	wg.Wait()
+
+	failed := false
+	for _, result := range results {
+		if result.msg != "" {
+			fmt.Println(result.msg)
+		}
+		failed = failed || result.failed
+	}
+	if failed {
+		os.Exit(1)
+	}
+	return nil
+}
+
+func invoke(exe string, args []string) (ok bool, output string) {
+	cmd := exec.Command(exe, args...)
+	out, err := cmd.CombinedOutput()
+	str := string(out)
+	if err != nil {
+		if str != "" {
+			return false, str
+		}
+		return false, err.Error()
+	}
+	return true, str
+}