// Copyright 2018 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package runtime import "unsafe" // Call fn with arg as its argument. Return what fn returns. // fn is the raw pc value of the entry point of the desired function. // Switches to the system stack, if not already there. // Preserves the calling point as the location where a profiler traceback will begin. //go:nosplit func libcCall(fn, arg unsafe.Pointer) int32 { // Leave caller's PC/SP/G around for traceback. gp := getg() var mp *m if gp != nil { mp = gp.m } if mp != nil { mp.libcallg.set(gp) mp.libcallpc = getcallerpc() // sp must be the last, because once async cpu profiler finds // all three values to be non-zero, it will use them mp.libcallsp = getcallersp() } res := asmcgocall(fn, arg) if mp != nil { mp.libcallsp = 0 } return res } // The *_trampoline functions convert from the Go calling convention to the C calling convention // and then call the underlying libc function. They are defined in sys_darwin_$ARCH.s. //go:nosplit //go:cgo_unsafe_args func pthread_attr_init(attr *pthreadattr) int32 { return libcCall(unsafe.Pointer(funcPC(pthread_attr_init_trampoline)), unsafe.Pointer(&attr)) } func pthread_attr_init_trampoline() //go:nosplit //go:cgo_unsafe_args func pthread_attr_setstacksize(attr *pthreadattr, size uintptr) int32 { return libcCall(unsafe.Pointer(funcPC(pthread_attr_setstacksize_trampoline)), unsafe.Pointer(&attr)) } func pthread_attr_setstacksize_trampoline() //go:nosplit //go:cgo_unsafe_args func pthread_attr_setdetachstate(attr *pthreadattr, state int) int32 { return libcCall(unsafe.Pointer(funcPC(pthread_attr_setdetachstate_trampoline)), unsafe.Pointer(&attr)) } func pthread_attr_setdetachstate_trampoline() //go:nosplit //go:cgo_unsafe_args func pthread_create(attr *pthreadattr, start uintptr, arg unsafe.Pointer) int32 { return libcCall(unsafe.Pointer(funcPC(pthread_create_trampoline)), unsafe.Pointer(&attr)) } func pthread_create_trampoline() //go:nosplit //go:cgo_unsafe_args func raise(sig uint32) { libcCall(unsafe.Pointer(funcPC(raise_trampoline)), unsafe.Pointer(&sig)) } func raise_trampoline() //go:nosplit //go:cgo_unsafe_args func pthread_self() (t pthread) { libcCall(unsafe.Pointer(funcPC(pthread_self_trampoline)), unsafe.Pointer(&t)) return } func pthread_self_trampoline() func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (unsafe.Pointer, int) { args := struct { addr unsafe.Pointer n uintptr prot, flags, fd int32 off uint32 ret1 unsafe.Pointer ret2 int }{addr, n, prot, flags, fd, off, nil, 0} libcCall(unsafe.Pointer(funcPC(mmap_trampoline)), unsafe.Pointer(&args)) return args.ret1, args.ret2 } func mmap_trampoline() //go:nosplit //go:cgo_unsafe_args func munmap(addr unsafe.Pointer, n uintptr) { libcCall(unsafe.Pointer(funcPC(munmap_trampoline)), unsafe.Pointer(&addr)) } func munmap_trampoline() //go:nosplit //go:cgo_unsafe_args func madvise(addr unsafe.Pointer, n uintptr, flags int32) { libcCall(unsafe.Pointer(funcPC(madvise_trampoline)), unsafe.Pointer(&addr)) } func madvise_trampoline() //go:nosplit //go:cgo_unsafe_args func read(fd int32, p unsafe.Pointer, n int32) int32 { return libcCall(unsafe.Pointer(funcPC(read_trampoline)), unsafe.Pointer(&fd)) } func read_trampoline() //go:nosplit //go:cgo_unsafe_args func closefd(fd int32) int32 { return libcCall(unsafe.Pointer(funcPC(close_trampoline)), unsafe.Pointer(&fd)) } func close_trampoline() //go:nosplit //go:cgo_unsafe_args func exit(code int32) { libcCall(unsafe.Pointer(funcPC(exit_trampoline)), unsafe.Pointer(&code)) } func exit_trampoline() //go:nosplit //go:cgo_unsafe_args func usleep(usec uint32) { libcCall(unsafe.Pointer(funcPC(usleep_trampoline)), unsafe.Pointer(&usec)) } func usleep_trampoline() //go:nosplit //go:cgo_unsafe_args func write(fd uintptr, p unsafe.Pointer, n int32) int32 { return libcCall(unsafe.Pointer(funcPC(write_trampoline)), unsafe.Pointer(&fd)) } func write_trampoline() //go:nosplit //go:cgo_unsafe_args func open(name *byte, mode, perm int32) (ret int32) { return libcCall(unsafe.Pointer(funcPC(open_trampoline)), unsafe.Pointer(&name)) } func open_trampoline() //go:nosplit //go:cgo_unsafe_args func nanotime() int64 { var r struct { t int64 // raw timer numer, denom uint32 // conversion factors. nanoseconds = t * numer / denom. } libcCall(unsafe.Pointer(funcPC(nanotime_trampoline)), unsafe.Pointer(&r)) // Note: Apple seems unconcerned about overflow here. See // https://developer.apple.com/library/content/qa/qa1398/_index.html // Note also, numer == denom == 1 is common. t := r.t if r.numer != 1 { t *= int64(r.numer) } if r.denom != 1 { t /= int64(r.denom) } return t } func nanotime_trampoline() //go:nosplit //go:cgo_unsafe_args func walltime() (int64, int32) { var t timeval libcCall(unsafe.Pointer(funcPC(walltime_trampoline)), unsafe.Pointer(&t)) return int64(t.tv_sec), 1000 * t.tv_usec } func walltime_trampoline() // Not used on Darwin, but must be defined. func exitThread(wait *uint32) { } // Tell the linker that the libc_* functions are to be found // in a system library, with the libc_ prefix missing. //go:cgo_import_dynamic libc_pthread_attr_init pthread_attr_init "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_pthread_attr_setstacksize pthread_attr_setstacksize "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_pthread_attr_setdetachstate pthread_attr_setdetachstate "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_pthread_create pthread_create "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_exit exit "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_raise raise "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_open open "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_close close "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_read read "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_write write "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_mmap mmap "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_munmap munmap "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_madvise madvise "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_error __error "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_usleep usleep "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_mach_timebase_info mach_timebase_info "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_mach_absolute_time mach_absolute_time "/usr/lib/libSystem.B.dylib" //go:cgo_import_dynamic libc_gettimeofday gettimeofday "/usr/lib/libSystem.B.dylib" // Magic incantation to get libSystem actually dynamically linked. // TODO: Why does the code require this? See cmd/compile/internal/ld/go.go:210 //go:cgo_import_dynamic _ _ "/usr/lib/libSystem.B.dylib"