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Diffstat (limited to 'vendor/github.com/cespare/xxhash/v2/xxhash_unsafe.go')
-rw-r--r--vendor/github.com/cespare/xxhash/v2/xxhash_unsafe.go57
1 files changed, 0 insertions, 57 deletions
diff --git a/vendor/github.com/cespare/xxhash/v2/xxhash_unsafe.go b/vendor/github.com/cespare/xxhash/v2/xxhash_unsafe.go
deleted file mode 100644
index 376e0ca2e..000000000
--- a/vendor/github.com/cespare/xxhash/v2/xxhash_unsafe.go
+++ /dev/null
@@ -1,57 +0,0 @@
-// +build !appengine
-
-// This file encapsulates usage of unsafe.
-// xxhash_safe.go contains the safe implementations.
-
-package xxhash
-
-import (
- "unsafe"
-)
-
-// In the future it's possible that compiler optimizations will make these
-// XxxString functions unnecessary by realizing that calls such as
-// Sum64([]byte(s)) don't need to copy s. See https://golang.org/issue/2205.
-// If that happens, even if we keep these functions they can be replaced with
-// the trivial safe code.
-
-// NOTE: The usual way of doing an unsafe string-to-[]byte conversion is:
-//
-// var b []byte
-// bh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
-// bh.Data = (*reflect.StringHeader)(unsafe.Pointer(&s)).Data
-// bh.Len = len(s)
-// bh.Cap = len(s)
-//
-// Unfortunately, as of Go 1.15.3 the inliner's cost model assigns a high enough
-// weight to this sequence of expressions that any function that uses it will
-// not be inlined. Instead, the functions below use a different unsafe
-// conversion designed to minimize the inliner weight and allow both to be
-// inlined. There is also a test (TestInlining) which verifies that these are
-// inlined.
-//
-// See https://github.com/golang/go/issues/42739 for discussion.
-
-// Sum64String computes the 64-bit xxHash digest of s.
-// It may be faster than Sum64([]byte(s)) by avoiding a copy.
-func Sum64String(s string) uint64 {
- b := *(*[]byte)(unsafe.Pointer(&sliceHeader{s, len(s)}))
- return Sum64(b)
-}
-
-// WriteString adds more data to d. It always returns len(s), nil.
-// It may be faster than Write([]byte(s)) by avoiding a copy.
-func (d *Digest) WriteString(s string) (n int, err error) {
- d.Write(*(*[]byte)(unsafe.Pointer(&sliceHeader{s, len(s)})))
- // d.Write always returns len(s), nil.
- // Ignoring the return output and returning these fixed values buys a
- // savings of 6 in the inliner's cost model.
- return len(s), nil
-}
-
-// sliceHeader is similar to reflect.SliceHeader, but it assumes that the layout
-// of the first two words is the same as the layout of a string.
-type sliceHeader struct {
- s string
- cap int
-}