go_darwin_arm64.go RawHistoryFolder
1// SPDX-License-Identifier: Apache-2.0
2// SPDX-FileCopyrightText: 2022 The Ebitengine Authors
3
4package fakecgo
5
6import "unsafe"
7
8//go:nosplit
9func _cgo_sys_thread_start(ts *ThreadStart) {
10 var attr pthread_attr_t
11 var ign, oset sigset_t
12 var p pthread_t
13 var size size_t
14 var err int
15
16 //fprintf(stderr, "runtime/cgo: _cgo_sys_thread_start: fn=%p, g=%p\n", ts->fn, ts->g); // debug
17 sigfillset(&ign)
18 pthread_sigmask(SIG_SETMASK, &ign, &oset)
19
20 pthread_attr_init(&attr)
21 pthread_attr_getstacksize(&attr, &size)
22 // Leave stacklo=0 and set stackhi=size; mstart will do the rest.
23 ts.g.stackhi = uintptr(size)
24
25 err = _cgo_try_pthread_create(&p, &attr, unsafe.Pointer(threadentry_trampolineABI0), ts)
26
27 pthread_sigmask(SIG_SETMASK, &oset, nil)
28
29 if err != 0 {
30 print("fakecgo: pthread_create failed: ")
31 println(err)
32 abort()
33 }
34}
35
36// threadentry_trampolineABI0 maps the C ABI to Go ABI then calls the Go function
37//
38//go:linkname x_threadentry_trampoline threadentry_trampoline
39var x_threadentry_trampoline byte
40var threadentry_trampolineABI0 = &x_threadentry_trampoline
41
42//go:nosplit
43func threadentry(v unsafe.Pointer) unsafe.Pointer {
44 ts := *(*ThreadStart)(v)
45 free(v)
46
47 // TODO: support ios
48 //#if TARGET_OS_IPHONE
49 // darwin_arm_init_thread_exception_port();
50 //#endif
51 setg_trampoline(setg_func, uintptr(unsafe.Pointer(ts.g)))
52
53 // faking funcs in go is a bit a... involved - but the following works :)
54 fn := uintptr(unsafe.Pointer(&ts.fn))
55 (*(*func())(unsafe.Pointer(&fn)))()
56
57 return nil
58}
59
60// here we will store a pointer to the provided setg func
61var setg_func uintptr
62
63// x_cgo_init(G *g, void (*setg)(void*)) (runtime/cgo/gcc_linux_amd64.c)
64// This get's called during startup, adjusts stacklo, and provides a pointer to setg_gcc for us
65// Additionally, if we set _cgo_init to non-null, go won't do it's own TLS setup
66// This function can't be go:systemstack since go is not in a state where the systemcheck would work.
67//
68//go:nosplit
69func x_cgo_init(g *G, setg uintptr) {
70 var size size_t
71 var attr pthread_attr_t
72
73 setg_func = setg
74 pthread_attr_init(&attr)
75 pthread_attr_getstacksize(&attr, &size)
76 g.stacklo = uintptr(unsafe.Pointer(&size)) - uintptr(size) + 4096
77 pthread_attr_destroy(&attr)
78
79 //TODO: support ios
80 //#if TARGET_OS_IPHONE
81 // darwin_arm_init_mach_exception_handler();
82 // darwin_arm_init_thread_exception_port();
83 // init_working_dir();
84 //#endif
85}