syscall: support ptrace on macOS/ARM64

Updates #38485.

Change-Id: I853966d934a8ee05cf62c7321f3e6271811d47b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/260718
Trust: Cherry Zhang <[email protected]>
Run-TryBot: Cherry Zhang <[email protected]>
TryBot-Result: Go Bot <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>

Author: cherrymui

src/syscall/syscall_darwin_arm64.go

@@ -7,11 +7,11 @@ package syscall
 import "unsafe"
 
 func setTimespec(sec, nsec int64) Timespec {
-	return Timespec{Sec: int64(sec), Nsec: int64(nsec)}
+	return Timespec{Sec: sec, Nsec: nsec}
 }
 
 func setTimeval(sec, usec int64) Timeval {
-	return Timeval{Sec: int64(sec), Usec: int32(usec)}
+	return Timeval{Sec: sec, Usec: int32(usec)}
 }
 
 //sys	Fstat(fd int, stat *Stat_t) (err error)
@@ -20,14 +20,8 @@ func setTimeval(sec, usec int64) Timeval {
 //sys	Lstat(path string, stat *Stat_t) (err error)
 //sys	Stat(path string, stat *Stat_t) (err error)
 //sys	Statfs(path string, stat *Statfs_t) (err error)
-//sys   fstatat(fd int, path string, stat *Stat_t, flags int) (err error)
-
-// Marked nosplit because it is called from forkAndExecInChild where
-// stack growth is forbidden.
-//go:nosplit
-func ptrace(request int, pid int, addr uintptr, data uintptr) error {
-	return ENOTSUP
-}
+//sys	fstatat(fd int, path string, stat *Stat_t, flags int) (err error)
+//sys	ptrace(request int, pid int, addr uintptr, data uintptr) (err error)
 
 func SetKevent(k *Kevent_t, fd, mode, flags int) {
 	k.Ident = uint64(fd)

src/syscall/zsyscall_darwin_arm64.go

@@ -249,3 +249,5 @@ TEXT ·libc_statfs_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_statfs(SB)
 TEXT ·libc_fstatat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_fstatat(SB)
+TEXT ·libc_ptrace_trampoline(SB),NOSPLIT,$0-0
+	JMP	libc_ptrace(SB)