| // Copyright 2013 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" | |
| var hardDiv bool // TODO: set if a hardware divider is available | |
| func lwp_mcontext_init(mc *mcontextt, stk unsafe.Pointer, mp *m, gp *g, fn uintptr) { | |
| // Machine dependent mcontext initialisation for LWP. | |
| mc.__gregs[_REG_R15] = uint32(funcPC(lwp_tramp)) | |
| mc.__gregs[_REG_R13] = uint32(uintptr(stk)) | |
| mc.__gregs[_REG_R0] = uint32(uintptr(unsafe.Pointer(mp))) | |
| mc.__gregs[_REG_R1] = uint32(uintptr(unsafe.Pointer(gp))) | |
| mc.__gregs[_REG_R2] = uint32(fn) | |
| } | |
| func checkgoarm() { | |
| // TODO(minux): FP checks like in os_linux_arm.go. | |
| // osinit not called yet, so ncpu not set: must use getncpu directly. | |
| if getncpu() > 1 && goarm < 7 { | |
| print("runtime: this system has multiple CPUs and must use\n") | |
| print("atomic synchronization instructions. Recompile using GOARM=7.\n") | |
| exit(1) | |
| } | |
| } | |
| //go:nosplit | |
| func cputicks() int64 { | |
| // Currently cputicks() is used in blocking profiler and to seed runtime·fastrand(). | |
| // runtime·nanotime() is a poor approximation of CPU ticks that is enough for the profiler. | |
| // TODO: need more entropy to better seed fastrand. | |
| return nanotime() | |
| } |