func runImage(bs []byte, dasm bool, n int) {
if dasm {
err := dasm8.DumpImage(bytes.NewReader(bs), os.Stdout)
if err != nil {
fmt.Println(err)
}
}
if len(bs) == 0 {
fmt.Println("(the image is empty)")
return
}
m := arch8.NewMachine(new(arch8.Config))
if err := m.LoadImageBytes(bs); err != nil {
fmt.Println(err)
return
}
ncycle, exp := m.Run(n)
fmt.Printf("(%d cycles)\n", ncycle)
if exp != nil {
if !arch8.IsHalt(exp) {
fmt.Println(exp)
err := arch8.FprintStack(os.Stdout, m, exp)
if err != nil {
fmt.Println(err)
}
}
} else {
fmt.Println("(end of time)")
}
}
func main() {
flag.Parse()
args := flag.Args()
if len(args) != 1 {
log.Fatal("need exactly one input file\n")
}
fname := args[0]
if *doDasm {
f, err := os.Open(fname)
defer f.Close()
err = dasm8.DumpImage(f, os.Stdout)
if err != nil {
log.Fatal(err)
}
} else if *printDebug {
f, err := os.Open(fname)
defer f.Close()
secs, err := e8.Read(f)
if err != nil {
log.Fatal(err)
}
for _, sec := range secs {
if sec.Type != e8.Debug {
continue
}
tab, err := debug8.UnmarshalTable(sec.Bytes)
if err != nil {
log.Fatal(err)
}
tab.PrintTo(os.Stdout)
}
} else {
bs, err := ioutil.ReadFile(fname)
if err != nil {
log.Fatal(err)
}
n, e := run(bs)
fmt.Printf("(%d cycles)\n", n)
if e != nil {
if !arch8.IsHalt(e) {
fmt.Println(e)
}
} else {
fmt.Println("(end of time)")
}
}
}
func main() {
flag.Parse()
args := flag.Args()
if len(args) != 1 {
log.Fatal("need exactly one input file\n")
}
fname := args[0]
var bs []byte
f, e := os.Open(fname)
if e != nil {
log.Fatalf("open: %s", e)
}
var es []*lex8.Error
if strings.HasSuffix(fname, "_bare.s") {
bs, es = asm8.BuildBareFunc(fname, f)
} else {
bs, es = asm8.BuildSingleFile(fname, f)
}
if len(es) > 0 {
for _, e := range es {
fmt.Println(e)
}
os.Exit(-1)
return
}
if *doDasm {
lines := dasm8.Dasm(bs, arch8.InitPC)
for _, line := range lines {
fmt.Println(line)
}
} else {
n, e := run(bs)
fmt.Printf("(%d cycles)\n", n)
if e != nil {
if !arch8.IsHalt(e) {
fmt.Println(e)
}
} else {
fmt.Println("(end of time)")
}
}
}
func run(bs []byte) (int, error) {
// create a single core machine
m := arch8.NewMachine(uint32(*memSize), 1)
secs, err := e8.Read(bytes.NewReader(bs))
if err != nil {
return 0, err
}
if err := m.LoadSections(secs); err != nil {
return 0, err
}
if *bootArg > math.MaxUint32 {
log.Fatalf("boot arg(%d) is too large", *bootArg)
}
if err := m.WriteWord(arch8.AddrBootArg, uint32(*bootArg)); err != nil {
return 0, err
}
if *romRoot != "" {
m.MountROM(*romRoot)
}
if *randSeed != 0 {
m.RandSeed(*randSeed)
}
ret, exp := m.Run(*ncycle)
if *printStatus {
m.PrintCoreStatus()
}
if !arch8.IsHalt(exp) {
fmt.Println(exp)
err := arch8.FprintStack(os.Stdout, m, exp)
if err != nil {
log.Fatal(err)
}
}
if exp == nil {
return ret, nil
}
return ret, exp
}
func run(bs []byte) (int, error) {
if *bootArg > math.MaxUint32 {
log.Fatalf("boot arg(%d) is too large", *bootArg)
}
// create a single core machine
m := arch8.NewMachine(&arch8.Config{
MemSize: uint32(*memSize),
ROM: *romRoot,
RandSeed: *randSeed,
BootArg: uint32(*bootArg),
})
secs, err := e8.Read(bytes.NewReader(bs))
if err != nil {
return 0, err
}
if err := m.LoadSections(secs); err != nil {
return 0, err
}
ret, exp := m.Run(*ncycle)
if *printStatus {
m.PrintCoreStatus()
}
if !arch8.IsHalt(exp) {
fmt.Println(exp)
err := arch8.FprintStack(os.Stdout, m, exp)
if err != nil {
log.Fatal(err)
}
}
if exp == nil {
return ret, nil
}
return ret, exp
}
func runImage(bs []byte, dasm bool, n int) {
if dasm {
err := dasm8.DumpImage(bytes.NewReader(bs), os.Stdout)
if err != nil {
fmt.Println(err)
}
}
if len(bs) == 0 {
fmt.Println("(the image is empty)")
return
}
ncycle, e := arch8.RunImage(bs, n)
fmt.Printf("(%d cycles)\n", ncycle)
if e != nil {
if !arch8.IsHalt(e) {
fmt.Println(e)
}
} else {
fmt.Println("(end of time)")
}
}
func runTests(
log lex8.Logger, tests map[string]uint32, img []byte, verbose bool,
) {
report := func(name string, pass bool, err error) {
if !pass {
lex8.LogError(log, fmt.Errorf("%s failed: got %s", name, err))
if verbose {
fmt.Println("FAILED")
}
return
}
if verbose {
fmt.Println("pass")
}
}
var testNames []string
for name := range tests {
testNames = append(testNames, name)
}
sort.Strings(testNames)
for _, test := range testNames {
if verbose {
fmt.Printf(" - %s: ", test)
}
arg := tests[test]
_, err := arch8.RunImageArg(img, arg)
if strings.HasPrefix(test, "TestBad") {
report(test, arch8.IsPanic(err), err)
} else {
report(test, arch8.IsHalt(err), err)
}
}
}
func TestMultiFile(t *testing.T) {
const N = 100000
o := func(fs map[string]string, output string) {
out, err := multiTestRun(t, fs, N)
if err == errRunFailed {
t.Error(err)
return
}
if !arch8.IsHalt(err) {
t.Log(fs)
t.Log(err)
t.Error("did not halt gracefully")
return
}
got := strings.TrimSpace(out)
expect := strings.TrimSpace(output)
if got != expect {
t.Log(fs)
t.Logf("expect: %s", expect)
t.Errorf("got: %s", got)
}
}
type files map[string]string
o(files{
"main/m.g": "func main() { }",
}, "")
o(files{
"a/a.g": "func P() { printInt(33) }",
"main/m.g": `
import ( "a" )
func main() { a.P() }`,
}, "33")
o(files{
"a/a.g": "struct A { func P() { printInt(33) } }",
"b/b.g": `import ("a"); var A a.A`,
"main/m.g": `import ("b"); func main() { b.A.P() }`,
}, "33")
o(files{
"a/a.g": "func init() { printInt(33) }",
"b/b.g": `import (_ "a"); func init() { printInt(44) }`,
"main/m.g": `import (_ "b"); func main() { printInt(55) }`,
}, "33\n44\n55")
o(files{
"a/a.g": "const A=33",
"main/m.g": `
import ("a")
var array [a.A]int
func main() { printInt(len(array)) }`,
}, "33")
o(files{
"a/a.g": "const A=33+5-2",
"main/m.g": `
import ("a")
var array [a.A-3]int
func main() { printInt(len(array)) }`,
}, "33")
o(files{
"asm/a/a.g": `
func F {
mov pc ret
}`,
"main/m.g": `
import ("asm/a")
func main() { a.F(); printInt(33) }`,
}, "33")
o(files{
"asm/a/a.g": `
func F {
addi r1 r0 33
mov pc ret
}`,
"main/m.g": `
import ("asm/a")
func f() int = a.F
func main() { printInt(f()) }`,
}, "33")
}
func TestBareFunc_good(t *testing.T) {
const N = 100000
o := func(input, output string) {
out, e := bareTestRun(t, input, N)
if e == errRunFailed {
t.Error(e)
return
}
if !arch8.IsHalt(e) {
t.Log(input)
t.Log(e)
t.Error("did not halt gracefully")
return
}
out = strings.TrimSpace(out)
output = strings.TrimSpace(output)
if out != output {
t.Log(input)
t.Logf("expect: %s", output)
t.Errorf("got: %s", out)
}
}
o(";;;;", "")
o("printInt(0)", "0")
o("printInt(3)", "3")
o("printInt(-444)", "-444")
o("printInt(2147483647)", "2147483647")
o("printInt(-2147483647-1)", "-2147483648")
o("printInt(-2147483648)", "-2147483648")
o("printInt(300000000)", "300000000")
o("printInt(4*5+3)", "23")
o("printInt(3+4*5)", "23")
o("printInt((3+4)*5)", "35")
o("printInt((5*(3+4)))", "35")
o("printInt(3^1)", "2")
o("printInt(0xf)", "15")
o("printInt(0xA)", "10")
o("a:=3; if a==3 { printInt(5) }", "5")
o("a:=5; if a==3 { printInt(5) }", "")
o("a:=5; if a==3 { printInt(5) } else { printInt(10) }", "10")
o("a:=3; for a>0 { printInt(a); a-- }", "3\n2\n1")
o("a:=0; for a<4 { printInt(a); a++ }", "0\n1\n2\n3")
o("for i:=0;i<3;i++ { printInt(i); }", "0\n1\n2")
o("for i:=0;i<10;i+=3 { printInt(i); }", "0\n3\n6\n9")
o("i:=3; for i:=0;i<3;i++ { printInt(i); }", "0\n1\n2")
o("i:=0; for ;i<3;i++ { printInt(i); }", "0\n1\n2")
o("a:=1; { a:=3; printInt(a) }", "3")
o("true:=3; printInt(true)", "3")
o("a,b:=3,4; printInt(a); printInt(b)", "3\n4")
o("a,b:=3,4; { a,b:=b,a; printInt(a); printInt(b) }", "4\n3")
o("a,b:=3,4; a,b=b,a; printInt(a); printInt(b)", "4\n3")
o("var a int; printInt(a)", "0")
o("var a (int); printInt(a)", "0")
o("var a,b = 3,4; printInt(a); printInt(b)", "3\n4")
o("var a,b = 3,4; printInt(a); printInt(b)", "3\n4")
o("var a,b int = 3,4; printInt(a); printInt(b)", "3\n4")
o("var a,b uint = 3,4; printUint(a); printUint(b)", "3\n4")
o(` a,b:=3,4; { var a,b=b,a; printInt(a); printInt(b) }
printInt(a); printInt(b)
`, "4\n3\n3\n4")
o("var i int; for i < 3 { printInt(i); i=i+1 }", "0\n1\n2")
o("for true { break }; printInt(3)", "3")
o("for true { if true break }; printInt(3)", "3")
o("for { break }; printInt(33)", "33")
o("i:=0; for i<3 { printInt(i); i=i+1; continue; break }", "0\n1\n2")
o("printChar('x')", "x")
o("var a=32; var b=*&a; printInt(b)", "32")
o("var a=32; var b=&a; var c=*b; printInt(c)", "32")
o("var a=32; var b int = *&*&a; printInt(b)", "32")
o("var a='x'; var b = *&*&a; printChar(b)", "x")
o("if nil==nil { printInt(3) }", "3")
o("if nil!=nil { printInt(3) }", "")
o("var a*int; if a==nil { printInt(3) }", "3")
o("var a*int; if nil==a { printInt(3) }", "3")
o("b:=3; a:=&b; if *a==3 { printInt(*a) }", "3")
o("b:=3; a:=&b; a=nil; if a==nil { printInt(b) }", "3")
o("b:=3; a:=&b; *a=4; printInt(b)", "4")
o("if true==true { printChar('y') }", "y")
o("if true!=true { printChar('y') }", "")
o("if true==false { printChar('y') }", "")
o("if true!=false { printChar('y') }", "y")
o("if false==false { printChar('y') }", "y")
o("if false!=false { printChar('y') }", "")
o("var a [4]int; a[3] = 3; printInt(a[3]); printInt(a[2])", "3\n0")
o("var a [7]int; a[3]=33; pt:=&a[3]; printInt(*pt)", "33")
o("var a [7]int; printInt(len(a))", "7")
o("var a [7]int; s:=a[:]; printInt(len(s))", "7")
o("var a [7]int; s:=a[:3]; printInt(len(s))", "3")
o("var a [7]int; s:=a[1:]; printInt(len(s))", "6")
o("var a [7]int; s:=a[1:3]; printInt(len(s))", "2")
o("var a [7]int; s:=a[0:0]; printInt(len(s))", "0")
o("var a [7]int; s:=a[:]; a[3]=33; printInt(s[3])", "33")
o("var a [7]int; s:=a[1:]; a[3]=33; printInt(s[2])", "33")
o("var a [7]int; s:=a[1:4]; a[3]=33; printInt(s[2])", "33")
o("var a [7]int; s:=a[:]; a[3]=33; pt:=&s[3]; printInt(*pt)", "33")
o("a:=3; a++; printInt(a)", "4")
o("a:=3; pt := &a; *pt++; printInt(a)", "4")
o("printInt(int(byte(int(-1))))", "255")
o("printInt(int(byte(3)))", "3")
o("printInt(int(byte(int(256))))", "0")
o("printInt(int(char(int(-1))))", "-1")
o("printInt(int(char(int(255))))", "-1")
o("printInt(int(char(int(256))))", "0")
o("printInt(int(byte(char(int(255)))))", "255")
o("printInt(int(byte(char(int(-1)))))", "255")
o("printInt(33 << uint(1))", "66")
o("printInt(33 << 1)", "66")
o("printInt(33 >> uint(1))", "16")
o("printInt(33 >> 1)", "16")
o("printInt(-33 >> uint(1))", "-17")
o("printInt(-1 >> uint(1))", "-1")
o("printInt(int(byte(255) << uint(1)))", "254")
o("printInt(int(byte(255) << 1))", "254")
o("printInt(int(uint(33) >> uint(1)))", "16")
o("printInt(int(uint(33) >> 1))", "16")
o("a:=3; a+=4; printInt(a)", "7")
o("a:=3; a-=4; printInt(a)", "-1")
o("a:=3; a*=4; printInt(a)", "12")
o("a:=3; a/=2; printInt(a)", "1")
o("a:=uint(3); a/=2; printUint(a)", "1")
o("a:=33; a<<=uint(1); printInt(a)", "66")
o("a:=33; a<<=1; printInt(a)", "66")
o("a:=33; a>>=uint(1); printInt(a)", "16")
o("a:=33; a>>=1; printInt(a)", "16")
o("a:=33; b:=(*uint)(&a); printUint(*b)", "33")
o("if 0x33 == 51 { printInt(33) }", "33")
o("const a = 33; printInt(a)", "33")
o("const a = 33; printUint(a)", "33")
o("const ( a,b=3,4; c=a+b ); printInt(a+b+c)", "14")
o("const a,b=3,4; var v [a+b]int; printInt(len(v))", "7")
}
func runTests(
log lex8.Logger, tests map[string]uint32, img []byte, opt *Options,
) {
logln := func(s string) {
if opt.LogLine == nil {
fmt.Println(s)
} else {
opt.LogLine(s)
}
}
// TODO(h8liu): this reporting should go with JSON for better formatting.
report := func(
name string, ncycle int, pass bool,
m *arch8.Machine, err error,
) {
if pass {
if opt.Verbose {
logln(fmt.Sprintf(
" - %s: passed (%s)", name, cycleStr(ncycle),
))
}
return
}
if err == nil {
err = errTimeOut
}
lex8.LogError(log, fmt.Errorf("%s failed: got %s", name, err))
if opt.Verbose {
logln(fmt.Sprintf(
" - %s: FAILED (%s, got %s)",
name, cycleStr(ncycle), err,
))
// TODO(h8liu): this is too ugly here...
excep, ok := err.(*arch8.CoreExcep)
if !arch8.IsHalt(err) && ok {
stackTrace := new(bytes.Buffer)
arch8.FprintStack(stackTrace, m, excep)
logln(stackTrace.String())
}
}
}
var testNames []string
for name := range tests {
testNames = append(testNames, name)
}
sort.Strings(testNames)
for _, test := range testNames {
arg := tests[test]
m := arch8.NewMachine(&arch8.Config{
BootArg: arg,
})
if err := m.LoadImageBytes(img); err != nil {
report(test, 0, false, m, err)
continue
}
var err error
n, excep := m.Run(opt.TestCycles)
if excep == nil {
err = errTimeOut
} else {
err = excep
}
if strings.HasPrefix(test, "TestBad") {
report(test, n, arch8.IsPanic(err), m, err)
} else {
report(test, n, arch8.IsHalt(err), m, err)
}
}
}
func TestSingleFile(t *testing.T) {
const N = 100000
o := func(input, output string) {
out, err := singleTestRun(t, input, N)
if err == errRunFailed {
t.Error(err)
return
}
if !arch8.IsHalt(err) {
t.Log(input)
t.Log(err)
t.Error("did not halt gracefully")
return
}
got := strings.TrimSpace(out)
expect := strings.TrimSpace(output)
if got != expect {
t.Log(input)
t.Logf("expect: %s", expect)
t.Errorf("got: %s", got)
}
}
o("func main() { }", "")
o("func main() { return }", "")
o("func main() { printInt(3) }", "3")
o(` func r() int { return 7 }
func main() { printInt(r()) }`,
"7")
o(` func p(i int) { printInt(i) }
func main() { p(33); p(44) }`,
"33\n44")
o(` func r() (int, int) { return 3, 4 }
func main() { a, b := r(); printInt(a); printInt(b) }`,
"3\n4")
o(` func r() (int, int) { return 3, 4 }
func p(a, b int) { printInt(a); printInt(b) }
func main() { p(r()) }`,
"3\n4")
o(` func r() (int) { return 3 }
func p(a, b int) { printInt(a); printInt(b) }
func main() { p(r(), 4) }`,
"3\n4")
o(` func fabo(n int) int {
if n == 0 return 0
if n == 1 return 1
return fabo(n-1) + fabo(n-2)
}
func main() { printInt(fabo(10)) }`,
"55")
o(` func b() bool { printInt(4); return true }
func main() { if false || b() { printInt(3) } }`,
"4\n3")
o(` func b() bool { printInt(4); return true }
func main() { if true || b() { printInt(3) } }`,
"3")
o(` func b() bool { printInt(4); return false }
func main() { if true && b() { printInt(3) } }`,
"4")
o(` func b() bool { printInt(4); return true }
func main() { if false && b() { printInt(3) } }`,
"")
o(` func b() bool { printInt(4); return true }
func main() { if true && b() { printInt(3) } }`,
"4\n3")
o(`func f(i int) { i=33; printInt(i) }; func main() { f(44) }`, "33")
o(` func f(a []int) { printInt(a[3]) }
func main() { var a [8]int; a[4]=33; f(a[1:5]) }`,
"33")
o(`func main() { for true { printInt(33); break } }`, "33")
o(`func main() { for 0==0 { printInt(33); break } }`, "33")
o(`func main() { for true && true { printInt(33); break } }`, "33")
o(`func main() { for true && false { printInt(33); break } }`, "")
o(`func main() { for 0==0 && 0==1 { printInt(33); break } }`, "")
o(`func main() { for true || false { printInt(33); break } }`, "33")
o(`func main() { for false || true { printInt(33); break } }`, "33")
o(`func main() { for false { printInt(33); break } }`, "")
o(` func printStr(s string) {
n:=len(s); for i:=0;i<n;i++ { printChar(s[i]) }
}
func main() { printStr("hello") }`, "hello")
o(` func printStr(s string) {
n:=len(s); for i:=0;i<n;i++ { printChar(s[i]) }
}
func main() { var a []int8; b:="hello"; a=b; printStr(a) }`, "hello")
o(` func printStr(s string) {
n:=len(s); for i:=0;i<n;i++ { printChar(s[i]) }
}
func main() { b:="hello"; var a []int8; a=b; printStr(b); _ := a }`,
"hello")
o(` struct A {}; func main() { var a A; pa := &a; _ := pa }`, "")
o(` struct A { a int }
func main() { var a A; printInt(a.a) }`, "0")
o(` struct A { a int }
func main() { var a A; a.a = 33; printInt(a.a) }`, "33")
o(` struct A { a int }
func main() { var a A; pi:=&a.a; *pi=33; printInt(a.a) }`, "33")
o(` struct A { a int }
func main() { var a A; (&a).a = 33; printInt(a.a) }`, "33")
o(` struct A { a int }
func main() { var a A; var pa=&a; pa.a = 33; printInt(pa.a) }`, "33")
o(` struct A { b byte; a int }
func main() { var a A; var pa=&a;
pa.a = 33; pa.b = byte(7);
printInt(pa.a); printInt(int(pa.b))
}`, "33\n7")
o(` func p(i int) { printInt(i) }
func main() { f:=p; f(33) }`, "33")
o(` func p(i int) { printInt(i+2) }
func c(x func(i int)) { x(33) }
func main() { c(p) }`, "35")
o("struct A { a *A }; func main() {}", "")
o(`struct A { b B }; struct B { a *A }; func main() {}`, "")
o(` struct A {}; func (p *A) p(a int) { printInt(a) }
func main() { var a A; a.p(33) }`, "33")
o(` struct A { a int }
func (p *A) s(a int) { p.a = a }
func (a *A) p() { printInt(a.a) }
func main() { var a A; a.s(33); a.p() }`, "33")
o(` struct A { a int }
func (p *A) s(a int) { (*p).a = a }
func (a *A) p() { printInt(a.a) }
func main() { var a A; a.s(33); a.p() }`, "33")
o(` struct A { a int }
func (a *A) p() { printInt(a.a) }
func (p *A) q(a int) { printInt(a) }
func main() { var a A; a.p(); a.a=33; a.p(); a.q(78) }`, "0\n33\n78")
o(` struct A { }
func (a *A) p() { printInt(33) }
func (a *A) q() { a.p() }
func main() { var a A; a.q() }`, "33")
o("var a int; func main() { a := 33; printInt(a) }", "33")
o(` struct A { }
func (a *A) p() { printInt(33) }
var a A
func main() { a.p() }`, "33")
o(` struct A { a int }
func (a *A) p() { printInt(a.a) }
var a A
func main() { a.a=33; a.p() }`, "33")
o(` struct A { a, b int }
func (a *A) p() { printInt(a.a+a.b) }
var a A
func main() { a.a=30; a.b=3; a.p() }`, "33")
o(` var ( a []int; s [2]int )
func main() { a=s[:]; s[1]=33; printInt(a[1]) }`, "33")
o(` var ( a []int )
func main() { if a == nil { printInt(33) } }`, "33")
o(` var ( a []int; v [0]int )
func main() { a=v[:]; if a != nil { printInt(33) } }`, "33")
o(` var ( a, b []int; v [3]int )
func main() { a=v[:2]; b = v[:3]; if a != b { printInt(33) } }`, "33")
o(` var ( a, b []int; v [3]int )
func main() { a=v[:]; b = v[:]; if a == b { printInt(33) } }`, "33")
o("func init() { printInt(33) }; func main() { printInt(44) }", "33\n44")
o(` struct a { a int; b byte }
func main() {
var x,y a; x.a=33; y.a=44;
printInt(x.a); printInt(y.a)
}`, "33\n44")
o(` struct a { a int; b,c byte }
func main() {
var as [4]a
printUint(uint(&as[1])-uint(&as[0]))
printUint(uint(&as[0].c)-uint(&as[0].a))
}`, "8\n5")
o(` struct a { a [4]byte; b byte }
func main() {
var as [4]a
printUint(uint(&as[1])-uint(&as[0]))
}`, "5")
o("import(); func main() {}", "")
o("import(); func main() { printInt(33) }", "33")
o("const a=33; func main() { printInt(a) }", "33")
o("const a=33; func main() { const a=34; printInt(a) }", "34")
o(` const a, b = 1, a; const c, d = d, 3
func main() { printInt(a); printInt(b); printInt(c); printInt(d) }`,
"1\n1\n3\n3\n")
o(`const a, b = b + 3, 30; func main() { printInt(a) }`, "33")
o(` var a [4]int
func main() {
s := make([]int, 2, &a[1])
s[0] = 33; s[1] = 47
printInt(a[1]); printInt(a[2])
}`, "33\n47")
o(`func f() int { for {} }; func main() { }`, "")
o(` func f() int { if true { return 1 } else { return 0 } }
func main() { }`, "")
o(`func f() int { for { if true { return 0 } } }; func main() { }`, "")
// Bugs found by the fuzzer in the past
o("func main() { a := 0==0; if a { printInt(33) } }", "33")
o(` func n()[(4-3)*1]string { var a [1]string; return a }
func main() { printInt(len(n())) }`, "1")
o(` func n()[1<<1]string { var a [2]string; return a }
func main() { printInt(len(n())) }`, "2")
o(` func n()[1>>1]string { var a [0]string; return a }
func main() { printInt(len(n())) }`, "0")
o("func main() { r:=+'0'; printChar(r) }", "0")
o("func n(b**bool) { **b=**b }; func main() {}", "")
o("func n(b****bool) { ****b=****b }; func main() {}", "")
o(` struct A { }
func (p *A) n() (a int) { return 33 }
func main() { var a A; printInt(a.n()) }`, "33")
o(` func main() {printInt(33)}
func _(){}
func _(){}
var _, _ int`, "33")
// Bugs found when writing OS8
o(` func main() { a, b := f(); printInt(a); printInt(len(b)) }
var dat [5]int
func f() (int, []int) { return 33, dat[:] }`, "33\n5")
o(` func p(a []uint) {}
func main() {
var t [10]uint; t2:=t[:];
before := uint(&t2[0]); p(t2[2:5]); after := uint(&t2[0])
if before != after { panic() }
}`, "")
}