all: add GOOS=ios

Introduce GOOS=ios for iOS systems. GOOS=ios matches "darwin"
build tag, like GOOS=android matches "linux" and GOOS=illumos
matches "solaris". Only ios/arm64 is supported (ios/amd64 is
not).

GOOS=ios and GOOS=darwin remain essentially the same at this
point. They will diverge at later time, to differentiate macOS
and iOS.

Uses of GOOS=="darwin" are changed to (GOOS=="darwin" || GOOS=="ios"),
except if it clearly means macOS (e.g. GOOS=="darwin" && GOARCH=="amd64"),
it remains GOOS=="darwin".

Updates #38485.

Change-Id: I4faacdc1008f42434599efb3c3ad90763a83b67c
Reviewed-on: https://go-review.googlesource.com/c/go/+/254740
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

31 files changed, 82 insertions, 20 deletions

diff --git a/src/runtime/debug/panic_test.go b/src/runtime/debug/panic_test.go
index 4b7830e100..93be216985 100644
--- a/src/runtime/debug/panic_test.go
+++ b/src/runtime/debug/panic_test.go
@@ -20,7 +20,7 @@ func TestPanicOnFault(t *testing.T) {
 	if runtime.GOARCH == "s390x" {
 		t.Skip("s390x fault addresses are missing the low order bits")
 	}
-	if runtime.GOOS == "darwin" && runtime.GOARCH == "arm64" {
+	if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && runtime.GOARCH == "arm64" {
 		t.Skip("darwin/arm64 doesn't provide fault addresses")
 	}
 	m, err := syscall.Mmap(-1, 0, 0x1000, syscall.PROT_READ /* Note: no PROT_WRITE */, syscall.MAP_SHARED|syscall.MAP_ANON)
diff --git a/src/runtime/internal/sys/gengoos.go b/src/runtime/internal/sys/gengoos.go
index 952b13649d..2a4bf0c3b4 100644
--- a/src/runtime/internal/sys/gengoos.go
+++ b/src/runtime/internal/sys/gengoos.go
@@ -44,6 +44,9 @@ func main() {
 	}
 
 	for _, target := range gooses {
+		if target == "nacl" {
+			continue
+		}
 		var buf bytes.Buffer
 		fmt.Fprintf(&buf, "// Code generated by gengoos.go using 'go generate'. DO NOT EDIT.\n\n")
 		if target == "linux" {
@@ -52,6 +55,9 @@ func main() {
 		if target == "solaris" {
 			fmt.Fprintf(&buf, "// +build !illumos\n") // must explicitly exclude illumos for solaris
 		}
+		if target == "darwin" {
+			fmt.Fprintf(&buf, "// +build !ios\n") // must explicitly exclude ios for darwin
+		}
 		fmt.Fprintf(&buf, "// +build %s\n\n", target) // must explicitly include target for bootstrapping purposes
 		fmt.Fprintf(&buf, "package sys\n\n")
 		fmt.Fprintf(&buf, "const GOOS = `%s`\n\n", target)
@@ -69,6 +75,9 @@ func main() {
 	}
 
 	for _, target := range goarches {
+		if target == "amd64p32" {
+			continue
+		}
 		var buf bytes.Buffer
 		fmt.Fprintf(&buf, "// Code generated by gengoos.go using 'go generate'. DO NOT EDIT.\n\n")
 		fmt.Fprintf(&buf, "// +build %s\n\n", target) // must explicitly include target for bootstrapping purposes
diff --git a/src/runtime/internal/sys/zgoos_aix.go b/src/runtime/internal/sys/zgoos_aix.go
index d97485c43c..0631d02aa5 100644
--- a/src/runtime/internal/sys/zgoos_aix.go
+++ b/src/runtime/internal/sys/zgoos_aix.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_android.go b/src/runtime/internal/sys/zgoos_android.go
index eec970b064..d356a40bec 100644
--- a/src/runtime/internal/sys/zgoos_android.go
+++ b/src/runtime/internal/sys/zgoos_android.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_darwin.go b/src/runtime/internal/sys/zgoos_darwin.go
index c40819ee55..6aa2db7e3a 100644
--- a/src/runtime/internal/sys/zgoos_darwin.go
+++ b/src/runtime/internal/sys/zgoos_darwin.go
@@ -1,5 +1,6 @@
 // Code generated by gengoos.go using 'go generate'. DO NOT EDIT.
 
+// +build !ios
 // +build darwin
 
 package sys
@@ -13,6 +14,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_dragonfly.go b/src/runtime/internal/sys/zgoos_dragonfly.go
index 3dc4edcc31..88ee1174f1 100644
--- a/src/runtime/internal/sys/zgoos_dragonfly.go
+++ b/src/runtime/internal/sys/zgoos_dragonfly.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 1
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_freebsd.go b/src/runtime/internal/sys/zgoos_freebsd.go
index 6c98b342f9..8de2ec0559 100644
--- a/src/runtime/internal/sys/zgoos_freebsd.go
+++ b/src/runtime/internal/sys/zgoos_freebsd.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 1
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_hurd.go b/src/runtime/internal/sys/zgoos_hurd.go
index d6dcc7bad4..183ccb02a1 100644
--- a/src/runtime/internal/sys/zgoos_hurd.go
+++ b/src/runtime/internal/sys/zgoos_hurd.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 1
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_illumos.go b/src/runtime/internal/sys/zgoos_illumos.go
index 17f4ecc34e..d04134e1df 100644
--- a/src/runtime/internal/sys/zgoos_illumos.go
+++ b/src/runtime/internal/sys/zgoos_illumos.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 1
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_ios.go b/src/runtime/internal/sys/zgoos_ios.go
new file mode 100644
index 0000000000..cf6e9d61f0
--- /dev/null
+++ b/src/runtime/internal/sys/zgoos_ios.go
@@ -0,0 +1,25 @@
+// Code generated by gengoos.go using 'go generate'. DO NOT EDIT.
+
+// +build ios
+
+package sys
+
+const GOOS = `ios`
+
+const GoosAix = 0
+const GoosAndroid = 0
+const GoosDarwin = 0
+const GoosDragonfly = 0
+const GoosFreebsd = 0
+const GoosHurd = 0
+const GoosIllumos = 0
+const GoosIos = 1
+const GoosJs = 0
+const GoosLinux = 0
+const GoosNacl = 0
+const GoosNetbsd = 0
+const GoosOpenbsd = 0
+const GoosPlan9 = 0
+const GoosSolaris = 0
+const GoosWindows = 0
+const GoosZos = 0
diff --git a/src/runtime/internal/sys/zgoos_js.go b/src/runtime/internal/sys/zgoos_js.go
index 74c9943d9b..1d9279ab38 100644
--- a/src/runtime/internal/sys/zgoos_js.go
+++ b/src/runtime/internal/sys/zgoos_js.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 1
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_linux.go b/src/runtime/internal/sys/zgoos_linux.go
index 1d5fcb0685..0f718d704f 100644
--- a/src/runtime/internal/sys/zgoos_linux.go
+++ b/src/runtime/internal/sys/zgoos_linux.go
@@ -14,6 +14,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 1
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_netbsd.go b/src/runtime/internal/sys/zgoos_netbsd.go
index 194fa6e432..2ae149ff13 100644
--- a/src/runtime/internal/sys/zgoos_netbsd.go
+++ b/src/runtime/internal/sys/zgoos_netbsd.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_openbsd.go b/src/runtime/internal/sys/zgoos_openbsd.go
index 2108691679..7d4d61e4ca 100644
--- a/src/runtime/internal/sys/zgoos_openbsd.go
+++ b/src/runtime/internal/sys/zgoos_openbsd.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_plan9.go b/src/runtime/internal/sys/zgoos_plan9.go
index e632a90b2e..30aec46df3 100644
--- a/src/runtime/internal/sys/zgoos_plan9.go
+++ b/src/runtime/internal/sys/zgoos_plan9.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_solaris.go b/src/runtime/internal/sys/zgoos_solaris.go
index 67b2ffbfcd..4bb8c99bce 100644
--- a/src/runtime/internal/sys/zgoos_solaris.go
+++ b/src/runtime/internal/sys/zgoos_solaris.go
@@ -14,6 +14,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_windows.go b/src/runtime/internal/sys/zgoos_windows.go
index cf2d6f4fb0..d1f4290204 100644
--- a/src/runtime/internal/sys/zgoos_windows.go
+++ b/src/runtime/internal/sys/zgoos_windows.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/internal/sys/zgoos_zos.go b/src/runtime/internal/sys/zgoos_zos.go
index e5d79accb4..d22be46fc0 100644
--- a/src/runtime/internal/sys/zgoos_zos.go
+++ b/src/runtime/internal/sys/zgoos_zos.go
@@ -13,6 +13,7 @@ const GoosDragonfly = 0
 const GoosFreebsd = 0
 const GoosHurd = 0
 const GoosIllumos = 0
+const GoosIos = 0
 const GoosJs = 0
 const GoosLinux = 0
 const GoosNacl = 0
diff --git a/src/runtime/malloc.go b/src/runtime/malloc.go
index e46327f9ce..4fa14996c2 100644
--- a/src/runtime/malloc.go
+++ b/src/runtime/malloc.go
@@ -207,7 +207,7 @@ const (
 	// arenaBaseOffset to offset into the top 4 GiB.
 	//
 	// WebAssembly currently has a limit of 4GB linear memory.
-	heapAddrBits = (_64bit*(1-sys.GoarchWasm)*(1-sys.GoosDarwin*sys.GoarchArm64))*48 + (1-_64bit+sys.GoarchWasm)*(32-(sys.GoarchMips+sys.GoarchMipsle)) + 33*sys.GoosDarwin*sys.GoarchArm64
+	heapAddrBits = (_64bit*(1-sys.GoarchWasm)*(1-(sys.GoosDarwin+sys.GoosIos)*sys.GoarchArm64))*48 + (1-_64bit+sys.GoarchWasm)*(32-(sys.GoarchMips+sys.GoarchMipsle)) + 33*(sys.GoosDarwin+sys.GoosIos)*sys.GoarchArm64
 
 	// maxAlloc is the maximum size of an allocation. On 64-bit,
 	// it's theoretically possible to allocate 1<<heapAddrBits bytes. On
@@ -521,7 +521,7 @@ func mallocinit() {
 		for i := 0x7f; i >= 0; i-- {
 			var p uintptr
 			switch {
-			case GOARCH == "arm64" && GOOS == "darwin":
+			case GOARCH == "arm64" && (GOOS == "darwin" || GOOS == "ios"):
 				p = uintptr(i)<<40 | uintptrMask&(0x0013<<28)
 			case GOARCH == "arm64":
 				p = uintptr(i)<<40 | uintptrMask&(0x0040<<32)
diff --git a/src/runtime/mgcscavenge.go b/src/runtime/mgcscavenge.go
index b74da1057a..9d6f551768 100644
--- a/src/runtime/mgcscavenge.go
+++ b/src/runtime/mgcscavenge.go
@@ -90,7 +90,7 @@ const (
 	//
 	// This ratio is used as part of multiplicative factor to help the scavenger account
 	// for the additional costs of using scavenged memory in its pacing.
-	scavengeCostRatio = 0.7 * sys.GoosDarwin
+	scavengeCostRatio = 0.7 * (sys.GoosDarwin + sys.GoosIos)
 
 	// scavengeReservationShards determines the amount of memory the scavenger
 	// should reserve for scavenging at a time. Specifically, the amount of
diff --git a/src/runtime/mkpreempt.go b/src/runtime/mkpreempt.go
index 44dea22ef3..c2e14cdcd6 100644
--- a/src/runtime/mkpreempt.go
+++ b/src/runtime/mkpreempt.go
@@ -361,6 +361,9 @@ func genARM64() {
 	p("#ifdef GOOS_darwin")
 	p("MOVD R30, (RSP)")
 	p("#endif")
+	p("#ifdef GOOS_ios")
+	p("MOVD R30, (RSP)")
+	p("#endif")
 
 	l.save()
 	p("CALL ·asyncPreempt2(SB)")
diff --git a/src/runtime/pprof/pprof_rusage.go b/src/runtime/pprof/pprof_rusage.go
index d42e6ed473..7954673811 100644
--- a/src/runtime/pprof/pprof_rusage.go
+++ b/src/runtime/pprof/pprof_rusage.go
@@ -19,7 +19,7 @@ func addMaxRSS(w io.Writer) {
 	switch runtime.GOOS {
 	case "linux", "android":
 		rssToBytes = 1024
-	case "darwin":
+	case "darwin", "ios":
 		rssToBytes = 1
 	default:
 		panic("unsupported OS")
diff --git a/src/runtime/pprof/pprof_test.go b/src/runtime/pprof/pprof_test.go
index 7149bfb31f..43307aeab9 100644
--- a/src/runtime/pprof/pprof_test.go
+++ b/src/runtime/pprof/pprof_test.go
@@ -262,7 +262,7 @@ func parseProfile(t *testing.T, valBytes []byte, f func(uintptr, []*profile.Loca
 // as interpreted by matches, and returns the parsed profile.
 func testCPUProfile(t *testing.T, matches matchFunc, need []string, avoid []string, f func(dur time.Duration)) *profile.Profile {
 	switch runtime.GOOS {
-	case "darwin":
+	case "darwin", "ios":
 		switch runtime.GOARCH {
 		case "arm64":
 			// nothing
@@ -280,7 +280,7 @@ func testCPUProfile(t *testing.T, matches matchFunc, need []string, avoid []stri
 
 	broken := false
 	switch runtime.GOOS {
-	case "darwin", "dragonfly", "netbsd", "illumos", "solaris":
+	case "darwin", "ios", "dragonfly", "netbsd", "illumos", "solaris":
 		broken = true
 	case "openbsd":
 		if runtime.GOARCH == "arm" || runtime.GOARCH == "arm64" {
diff --git a/src/runtime/preempt_arm64.s b/src/runtime/preempt_arm64.s
index 3c27b52de1..d0e77659c3 100644
--- a/src/runtime/preempt_arm64.s
+++ b/src/runtime/preempt_arm64.s
@@ -13,6 +13,9 @@ TEXT ·asyncPreempt(SB),NOSPLIT|NOFRAME,$0-0
 	#ifdef GOOS_darwin
 	MOVD R30, (RSP)
 	#endif
+	#ifdef GOOS_ios
+	MOVD R30, (RSP)
+	#endif
 	MOVD R0, 8(RSP)
 	MOVD R1, 16(RSP)
 	MOVD R2, 24(RSP)
diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index 5b6a30d40b..a1e2ed0680 100644
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -503,7 +503,7 @@ func cpuinit() {
 	var env string
 
 	switch GOOS {
-	case "aix", "darwin", "dragonfly", "freebsd", "netbsd", "openbsd", "illumos", "solaris", "linux":
+	case "aix", "darwin", "ios", "dragonfly", "freebsd", "netbsd", "openbsd", "illumos", "solaris", "linux":
 		cpu.DebugOptions = true
 
 		// Similar to goenv_unix but extracts the environment value for
@@ -1158,7 +1158,7 @@ func mstart() {
 
 	// Exit this thread.
 	switch GOOS {
-	case "windows", "solaris", "illumos", "plan9", "darwin", "aix":
+	case "windows", "solaris", "illumos", "plan9", "darwin", "ios", "aix":
 		// Windows, Solaris, illumos, Darwin, AIX and Plan 9 always system-allocate
 		// the stack, but put it in _g_.stack before mstart,
 		// so the logic above hasn't set osStack yet.
@@ -1487,7 +1487,7 @@ func allocm(_p_ *p, fn func(), id int64) *m {
 
 	// In case of cgo or Solaris or illumos or Darwin, pthread_create will make us a stack.
 	// Windows and Plan 9 will layout sched stack on OS stack.
-	if iscgo || GOOS == "solaris" || GOOS == "illumos" || GOOS == "windows" || GOOS == "plan9" || GOOS == "darwin" {
+	if iscgo || GOOS == "solaris" || GOOS == "illumos" || GOOS == "windows" || GOOS == "plan9" || GOOS == "darwin" || GOOS == "ios" {
 		mp.g0 = malg(-1)
 	} else {
 		mp.g0 = malg(8192 * sys.StackGuardMultiplier)
@@ -4077,7 +4077,7 @@ func sigprof(pc, sp, lr uintptr, gp *g, mp *m) {
 		// Normal traceback is impossible or has failed.
 		// See if it falls into several common cases.
 		n = 0
-		if (GOOS == "windows" || GOOS == "solaris" || GOOS == "illumos" || GOOS == "darwin" || GOOS == "aix") && mp.libcallg != 0 && mp.libcallpc != 0 && mp.libcallsp != 0 {
+		if (GOOS == "windows" || GOOS == "solaris" || GOOS == "illumos" || GOOS == "darwin" || GOOS == "ios" || GOOS == "aix") && mp.libcallg != 0 && mp.libcallpc != 0 && mp.libcallsp != 0 {
 			// Libcall, i.e. runtime syscall on windows.
 			// Collect Go stack that leads to the call.
 			n = gentraceback(mp.libcallpc, mp.libcallsp, 0, mp.libcallg.ptr(), 0, &stk[0], len(stk), nil, nil, 0)
diff --git a/src/runtime/runtime2.go b/src/runtime/runtime2.go
index 9652b6a5a4..48e07f789b 100644
--- a/src/runtime/runtime2.go
+++ b/src/runtime/runtime2.go
@@ -1060,4 +1060,4 @@ var (
 )
 
 // Must agree with cmd/internal/objabi.Framepointer_enabled.
-const framepointer_enabled = GOARCH == "amd64" || GOARCH == "arm64" && (GOOS == "linux" || GOOS == "darwin")
+const framepointer_enabled = GOARCH == "amd64" || GOARCH == "arm64" && (GOOS == "linux" || GOOS == "darwin" || GOOS == "ios")
diff --git a/src/runtime/signal_unix.go b/src/runtime/signal_unix.go
index bbfc18e37b..a3d6f34c88 100644
--- a/src/runtime/signal_unix.go
+++ b/src/runtime/signal_unix.go
@@ -346,7 +346,7 @@ const preemptMSupported = true
 // safe-point, it will preempt the goroutine. It always atomically
 // increments mp.preemptGen after handling a preemption request.
 func preemptM(mp *m) {
-	if GOOS == "darwin" && GOARCH == "arm64" && !iscgo {
+	if (GOOS == "darwin" || GOOS == "ios") && GOARCH == "arm64" && !iscgo {
 		// On darwin, we use libc calls, and cgo is required on ARM64
 		// so we have TLS set up to save/restore G during C calls. If cgo is
 		// absent, we cannot save/restore G in TLS, and if a signal is
@@ -975,7 +975,7 @@ func sigfwdgo(sig uint32, info *siginfo, ctx unsafe.Pointer) bool {
 	// This function and its caller sigtrampgo assumes SIGPIPE is delivered on the
 	// originating thread. This property does not hold on macOS (golang.org/issue/33384),
 	// so we have no choice but to ignore SIGPIPE.
-	if GOOS == "darwin" && sig == _SIGPIPE {
+	if (GOOS == "darwin" || GOOS == "ios") && sig == _SIGPIPE {
 		return true
 	}
 
diff --git a/src/runtime/sigqueue.go b/src/runtime/sigqueue.go
index 3bf07cb5a6..0605f5da80 100644
--- a/src/runtime/sigqueue.go
+++ b/src/runtime/sigqueue.go
@@ -105,7 +105,7 @@ Send:
 			break Send
 		case sigReceiving:
 			if atomic.Cas(&sig.state, sigReceiving, sigIdle) {
-				if GOOS == "darwin" {
+				if GOOS == "darwin" || GOOS == "ios" {
 					sigNoteWakeup(&sig.note)
 					break Send
 				}
@@ -140,7 +140,7 @@ func signal_recv() uint32 {
 				throw("signal_recv: inconsistent state")
 			case sigIdle:
 				if atomic.Cas(&sig.state, sigIdle, sigReceiving) {
-					if GOOS == "darwin" {
+					if GOOS == "darwin" || GOOS == "ios" {
 						sigNoteSleep(&sig.note)
 						break Receive
 					}
@@ -194,7 +194,7 @@ func signal_enable(s uint32) {
 	if !sig.inuse {
 		// This is the first call to signal_enable. Initialize.
 		sig.inuse = true // enable reception of signals; cannot disable
-		if GOOS == "darwin" {
+		if GOOS == "darwin" || GOOS == "ios" {
 			sigNoteSetup(&sig.note)
 		} else {
 			noteclear(&sig.note)
diff --git a/src/runtime/stack.go b/src/runtime/stack.go
index adcef071da..3802cd049e 100644
--- a/src/runtime/stack.go
+++ b/src/runtime/stack.go
@@ -66,7 +66,7 @@ const (
 	// to each stack below the usual guard area for OS-specific
 	// purposes like signal handling. Used on Windows, Plan 9,
 	// and iOS because they do not use a separate stack.
-	_StackSystem = sys.GoosWindows*512*sys.PtrSize + sys.GoosPlan9*512 + sys.GoosDarwin*sys.GoarchArm64*1024
+	_StackSystem = sys.GoosWindows*512*sys.PtrSize + sys.GoosPlan9*512 + (sys.GoosDarwin+sys.GoosIos)*sys.GoarchArm64*1024
 
 	// The minimum size of stack used by Go code
 	_StackMin = 2048
diff --git a/src/runtime/tls_arm64.h b/src/runtime/tls_arm64.h
index f60f4f6d5b..0804fa3502 100644
--- a/src/runtime/tls_arm64.h
+++ b/src/runtime/tls_arm64.h
@@ -15,6 +15,12 @@
 #endif
 
 #ifdef GOOS_darwin
+#define TLS_darwin
+#endif
+#ifdef GOOS_ios
+#define TLS_darwin
+#endif
+#ifdef TLS_darwin
 #define TPIDR TPIDRRO_EL0
 #define TLSG_IS_VARIABLE
 #define MRS_TPIDR_R0 WORD $0xd53bd060 // MRS TPIDRRO_EL0, R0
diff --git a/src/runtime/tls_arm64.s b/src/runtime/tls_arm64.s
index 999914d655..7846fac6c5 100644
--- a/src/runtime/tls_arm64.s
+++ b/src/runtime/tls_arm64.s
@@ -13,7 +13,7 @@ TEXT runtime·load_g(SB),NOSPLIT,$0
 	CBZ	R0, nocgo
 
 	MRS_TPIDR_R0
-#ifdef GOOS_darwin
+#ifdef TLS_darwin
 	// Darwin sometimes returns unaligned pointers
 	AND	$0xfffffffffffffff8, R0
 #endif
@@ -29,7 +29,7 @@ TEXT runtime·save_g(SB),NOSPLIT,$0
 	CBZ	R0, nocgo
 
 	MRS_TPIDR_R0
-#ifdef GOOS_darwin
+#ifdef TLS_darwin
 	// Darwin sometimes returns unaligned pointers
 	AND	$0xfffffffffffffff8, R0
 #endif