all: add flag for setting the goroutine stack size

This is helpful in some cases where the default stack size isn't big
enough.

builder/build.go

@@ -178,7 +178,7 @@ func Build(pkgName, outpath string, config *compileopts.Config, action func(Buil
 
 		Scheduler:          config.Scheduler(),
 		AutomaticStackSize: config.AutomaticStackSize(),
-		DefaultStackSize:   config.Target.DefaultStackSize,
+		DefaultStackSize:   config.StackSize(),
 		NeedsStackObjects:  config.NeedsStackObjects(),
 		Debug:              true,
 	}

compileopts/config.go

@@ -175,6 +175,15 @@ func (c *Config) AutomaticStackSize() bool {
 	return false
 }
 
+// StackSize returns the default stack size to be used for goroutines, if the
+// stack size could not be determined automatically at compile time.
+func (c *Config) StackSize() uint64 {
+	if c.Options.StackSize != 0 {
+		return c.Options.StackSize
+	}
+	return c.Target.DefaultStackSize
+}
+
 // UseThinLTO returns whether ThinLTO should be used for the given target. Some
 // targets (such as wasm) are not yet supported.
 // We should try and remove as many exceptions as possible in the future, so

compileopts/options.go

@@ -28,6 +28,7 @@ type Options struct {
 	GC              string
 	PanicStrategy   string
 	Scheduler       string
+	StackSize       uint64 // goroutine stack size (if none could be automatically determined)
 	Serial          string
 	Work            bool // -work flag to print temporary build directory
 	InterpTimeout   time.Duration

compiler/compiler_test.go

@@ -79,7 +79,7 @@ func TestCompiler(t *testing.T) {
 				RelocationModel:    config.RelocationModel(),
 				Scheduler:          config.Scheduler(),
 				AutomaticStackSize: config.AutomaticStackSize(),
-				DefaultStackSize:   config.Target.DefaultStackSize,
+				DefaultStackSize:   config.StackSize(),
 				NeedsStackObjects:  config.NeedsStackObjects(),
 			}
 			machine, err := NewTargetMachine(compilerConfig)

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/chromedp/chromedp v0.7.6
 	github.com/gofrs/flock v0.8.1
 	github.com/google/shlex v0.0.0-20181106134648-c34317bd91bf
+	github.com/inhies/go-bytesize v0.0.0-20220417184213-4913239db9cf
 	github.com/marcinbor85/gohex v0.0.0-20200531091804-343a4b548892
 	github.com/mattn/go-colorable v0.1.8
 	go.bug.st/serial v1.3.5

go.sum

@@ -22,6 +22,8 @@ github.com/gofrs/flock v0.8.1 h1:+gYjHKf32LDeiEEFhQaotPbLuUXjY5ZqxKgXy7n59aw=
 github.com/gofrs/flock v0.8.1/go.mod h1:F1TvTiK9OcQqauNUHlbJvyl9Qa1QvF/gOUDKA14jxHU=
 github.com/google/shlex v0.0.0-20181106134648-c34317bd91bf h1:7+FW5aGwISbqUtkfmIpZJGRgNFg2ioYPvFaUxdqpDsg=
 github.com/google/shlex v0.0.0-20181106134648-c34317bd91bf/go.mod h1:RpwtwJQFrIEPstU94h88MWPXP2ektJZ8cZ0YntAmXiE=
+github.com/inhies/go-bytesize v0.0.0-20220417184213-4913239db9cf h1:FtEj8sfIcaaBfAKrE1Cwb61YDtYq9JxChK1c7AKce7s=
+github.com/inhies/go-bytesize v0.0.0-20220417184213-4913239db9cf/go.mod h1:yrqSXGoD/4EKfF26AOGzscPOgTTJcyAwM2rpixWT+t4=
 github.com/josharian/intern v1.0.0 h1:vlS4z54oSdjm0bgjRigI+G1HpF+tI+9rE5LLzOg8HmY=
 github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=
 github.com/mailru/easyjson v0.7.7 h1:UGYAvKxe3sBsEDzO8ZeWOSlIQfWFlxbzLZe7hwFURr0=

main.go

@@ -26,6 +26,7 @@ import (
 	"time"
 
 	"github.com/google/shlex"
+	"github.com/inhies/go-bytesize"
 	"github.com/mattn/go-colorable"
 	"github.com/tinygo-org/tinygo/builder"
 	"github.com/tinygo-org/tinygo/compileopts"
@@ -1318,6 +1319,12 @@ func main() {
 	var tags buildutil.TagsFlag
 	flag.Var(&tags, "tags", "a space-separated list of extra build tags")
 	target := flag.String("target", "", "chip/board name or JSON target specification file")
+	var stackSize uint64
+	flag.Func("stack-size", "goroutine stack size (if unknown at compile time)", func(s string) error {
+		size, err := bytesize.Parse(s)
+		stackSize = uint64(size)
+		return err
+	})
 	printSize := flag.String("size", "", "print sizes (none, short, full)")
 	printStacks := flag.Bool("print-stacks", false, "print stack sizes of goroutines")
 	printAllocsString := flag.String("print-allocs", "", "regular expression of functions for which heap allocations should be printed")
@@ -1398,6 +1405,7 @@ func main() {
 		GOARCH:          goenv.Get("GOARCH"),
 		GOARM:           goenv.Get("GOARM"),
 		Target:          *target,
+		StackSize:       stackSize,
 		Opt:             *opt,
 		GC:              *gc,
 		PanicStrategy:   *panicStrategy,

transform/stacksize.go

@@ -40,7 +40,7 @@ func CreateStackSizeLoads(mod llvm.Module, config *compileopts.Config) []string
 	stackSizesGlobal := llvm.AddGlobal(mod, stackSizesGlobalType, "internal/task.stackSizes")
 	stackSizesGlobal.SetSection(".tinygo_stacksizes")
 	defaultStackSizes := make([]llvm.Value, len(functions))
-	defaultStackSize := llvm.ConstInt(functions[0].Type(), config.Target.DefaultStackSize, false)
+	defaultStackSize := llvm.ConstInt(functions[0].Type(), config.StackSize(), false)
 	for i := range defaultStackSizes {
 		defaultStackSizes[i] = defaultStackSize
 	}

transform/stacksize_test.go

@@ -13,6 +13,7 @@ func TestCreateStackSizeLoads(t *testing.T) {
 	testTransform(t, "testdata/stacksize", func(mod llvm.Module) {
 		// Run optimization pass.
 		transform.CreateStackSizeLoads(mod, &compileopts.Config{
+			Options: &compileopts.Options{},
 			Target: &compileopts.TargetSpec{
 				DefaultStackSize: 1024,
 			},