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// Copyright ©2015 The Gonum Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
//go:build safe
// +build safe
package mat
import "reflect"
var sizeOfFloat64 = int(reflect.TypeOf(float64(0)).Size())
// offset returns the number of float64 values b[0] is after a[0].
func offset(a, b []float64) int {
va0 := reflect.ValueOf(a).Index(0)
vb0 := reflect.ValueOf(b).Index(0)
if va0.Addr() == vb0.Addr() {
return 0
}
// This expression must be atomic with respect to GC moves.
// At this stage this is true, because the GC does not
// move. See https://golang.org/issue/12445.
return int(vb0.UnsafeAddr()-va0.UnsafeAddr()) / sizeOfFloat64
}
var sizeOfComplex128 = int(reflect.TypeOf(complex128(0)).Size())
// offsetComplex returns the number of complex128 values b[0] is after a[0].
func offsetComplex(a, b []complex128) int {
va0 := reflect.ValueOf(a).Index(0)
vb0 := reflect.ValueOf(b).Index(0)
if va0.Addr() == vb0.Addr() {
return 0
}
// This expression must be atomic with respect to GC moves.
// At this stage this is true, because the GC does not
// move. See https://golang.org/issue/12445.
return int(vb0.UnsafeAddr()-va0.UnsafeAddr()) / sizeOfComplex128
}
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