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authordavy <davy.wybiral@gmail.com>2019-07-03 16:55:03 -0500
committerdavy <davy.wybiral@gmail.com>2019-07-03 16:55:03 -0500
commit442e3c6dcf35cc1ca508e617f94198637e761bc8 (patch)
tree8d6b6210ce98385180766fa14984e2c47f779050 /vendor/golang.org/x/sys/cpu/cpu_linux.go
parent53bc0c19fadcfb7ae9a608ed1f9f6268d1670368 (diff)
dep ensurev0.1.0
Diffstat (limited to 'vendor/golang.org/x/sys/cpu/cpu_linux.go')
-rw-r--r--vendor/golang.org/x/sys/cpu/cpu_linux.go59
1 files changed, 59 insertions, 0 deletions
diff --git a/vendor/golang.org/x/sys/cpu/cpu_linux.go b/vendor/golang.org/x/sys/cpu/cpu_linux.go
new file mode 100644
index 0000000..76b5f50
--- /dev/null
+++ b/vendor/golang.org/x/sys/cpu/cpu_linux.go
@@ -0,0 +1,59 @@
+// 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.
+
+//+build !amd64,!amd64p32,!386
+
+package cpu
+
+import (
+ "io/ioutil"
+)
+
+const (
+ _AT_HWCAP = 16
+ _AT_HWCAP2 = 26
+
+ procAuxv = "/proc/self/auxv"
+
+ uintSize = int(32 << (^uint(0) >> 63))
+)
+
+// For those platforms don't have a 'cpuid' equivalent we use HWCAP/HWCAP2
+// These are initialized in cpu_$GOARCH.go
+// and should not be changed after they are initialized.
+var hwCap uint
+var hwCap2 uint
+
+func init() {
+ buf, err := ioutil.ReadFile(procAuxv)
+ if err != nil {
+ // e.g. on android /proc/self/auxv is not accessible, so silently
+ // ignore the error and leave Initialized = false
+ return
+ }
+
+ bo := hostByteOrder()
+ for len(buf) >= 2*(uintSize/8) {
+ var tag, val uint
+ switch uintSize {
+ case 32:
+ tag = uint(bo.Uint32(buf[0:]))
+ val = uint(bo.Uint32(buf[4:]))
+ buf = buf[8:]
+ case 64:
+ tag = uint(bo.Uint64(buf[0:]))
+ val = uint(bo.Uint64(buf[8:]))
+ buf = buf[16:]
+ }
+ switch tag {
+ case _AT_HWCAP:
+ hwCap = val
+ case _AT_HWCAP2:
+ hwCap2 = val
+ }
+ }
+ doinit()
+
+ Initialized = true
+}