github.com/ebitengine/purego@v0.8.0-alpha.2.0.20240512170805-6cd12240d332/internal/fakecgo/go_darwin_arm64.go (about) 1 // Copyright 2011 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 //go:build !cgo 6 7 package fakecgo 8 9 import "unsafe" 10 11 //go:nosplit 12 //go:norace 13 func _cgo_sys_thread_start(ts *ThreadStart) { 14 var attr pthread_attr_t 15 var ign, oset sigset_t 16 var p pthread_t 17 var size size_t 18 var err int 19 20 sigfillset(&ign) 21 pthread_sigmask(SIG_SETMASK, &ign, &oset) 22 23 size = pthread_get_stacksize_np(pthread_self()) 24 pthread_attr_init(&attr) 25 pthread_attr_setstacksize(&attr, size) 26 // Leave stacklo=0 and set stackhi=size; mstart will do the rest. 27 ts.g.stackhi = uintptr(size) 28 29 err = _cgo_try_pthread_create(&p, &attr, unsafe.Pointer(threadentry_trampolineABI0), ts) 30 31 pthread_sigmask(SIG_SETMASK, &oset, nil) 32 33 if err != 0 { 34 print("fakecgo: pthread_create failed: ") 35 println(err) 36 abort() 37 } 38 } 39 40 // threadentry_trampolineABI0 maps the C ABI to Go ABI then calls the Go function 41 // 42 //go:linkname x_threadentry_trampoline threadentry_trampoline 43 var x_threadentry_trampoline byte 44 var threadentry_trampolineABI0 = &x_threadentry_trampoline 45 46 //go:nosplit 47 //go:norace 48 func threadentry(v unsafe.Pointer) unsafe.Pointer { 49 ts := *(*ThreadStart)(v) 50 free(v) 51 52 // TODO: support ios 53 //#if TARGET_OS_IPHONE 54 // darwin_arm_init_thread_exception_port(); 55 //#endif 56 setg_trampoline(setg_func, uintptr(unsafe.Pointer(ts.g))) 57 58 // faking funcs in go is a bit a... involved - but the following works :) 59 fn := uintptr(unsafe.Pointer(&ts.fn)) 60 (*(*func())(unsafe.Pointer(&fn)))() 61 62 return nil 63 } 64 65 // here we will store a pointer to the provided setg func 66 var setg_func uintptr 67 68 // x_cgo_init(G *g, void (*setg)(void*)) (runtime/cgo/gcc_linux_amd64.c) 69 // This get's called during startup, adjusts stacklo, and provides a pointer to setg_gcc for us 70 // Additionally, if we set _cgo_init to non-null, go won't do it's own TLS setup 71 // This function can't be go:systemstack since go is not in a state where the systemcheck would work. 72 // 73 //go:nosplit 74 //go:norace 75 func x_cgo_init(g *G, setg uintptr) { 76 var size size_t 77 78 setg_func = setg 79 size = pthread_get_stacksize_np(pthread_self()) 80 g.stacklo = uintptr(unsafe.Add(unsafe.Pointer(&size), -size+4096)) 81 82 //TODO: support ios 83 //#if TARGET_OS_IPHONE 84 // darwin_arm_init_mach_exception_handler(); 85 // darwin_arm_init_thread_exception_port(); 86 // init_working_dir(); 87 //#endif 88 }