| // Copyright 2012 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 "internal/cpu" |
| |
| const ( |
| _HWCAP_VFP = 1 << 6 |
| _HWCAP_VFPv3 = 1 << 13 |
| ) |
| |
| func checkgoarm() { |
| if goarm > 5 && cpu.HWCap&_HWCAP_VFP == 0 { |
| print("runtime: this CPU has no floating point hardware, so it cannot run\n") |
| print("this GOARM=", goarm, " binary. Recompile using GOARM=5.\n") |
| exit(1) |
| } |
| if goarm > 6 && cpu.HWCap&_HWCAP_VFPv3 == 0 { |
| print("runtime: this CPU has no VFPv3 floating point hardware, so it cannot run\n") |
| print("this GOARM=", goarm, " binary. Recompile using GOARM=5 or GOARM=6.\n") |
| exit(1) |
| } |
| |
| // 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) |
| } |
| } |
| |
| func archauxv(tag, val uintptr) { |
| switch tag { |
| case _AT_HWCAP: |
| cpu.HWCap = uint(val) |
| case _AT_HWCAP2: |
| cpu.HWCap2 = uint(val) |
| } |
| } |
| |
| //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. |
| return nanotime() |
| } |