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-rw-r--r--vendor/github.com/golang/geo/s2/bits_go18.go53
1 files changed, 0 insertions, 53 deletions
diff --git a/vendor/github.com/golang/geo/s2/bits_go18.go b/vendor/github.com/golang/geo/s2/bits_go18.go
deleted file mode 100644
index 10a674da5..000000000
--- a/vendor/github.com/golang/geo/s2/bits_go18.go
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright 2018 Google Inc. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build !go1.9
-
-package s2
-
-// This file is for the bit manipulation code pre-Go 1.9.
-
-// findMSBSetNonZero64 returns the index (between 0 and 63) of the most
-// significant set bit. Passing zero to this function returns zero.
-func findMSBSetNonZero64(x uint64) int {
- val := []uint64{0x2, 0xC, 0xF0, 0xFF00, 0xFFFF0000, 0xFFFFFFFF00000000}
- shift := []uint64{1, 2, 4, 8, 16, 32}
- var msbPos uint64
- for i := 5; i >= 0; i-- {
- if x&val[i] != 0 {
- x >>= shift[i]
- msbPos |= shift[i]
- }
- }
- return int(msbPos)
-}
-
-const deBruijn64 = 0x03f79d71b4ca8b09
-const digitMask = uint64(1<<64 - 1)
-
-var deBruijn64Lookup = []byte{
- 0, 1, 56, 2, 57, 49, 28, 3, 61, 58, 42, 50, 38, 29, 17, 4,
- 62, 47, 59, 36, 45, 43, 51, 22, 53, 39, 33, 30, 24, 18, 12, 5,
- 63, 55, 48, 27, 60, 41, 37, 16, 46, 35, 44, 21, 52, 32, 23, 11,
- 54, 26, 40, 15, 34, 20, 31, 10, 25, 14, 19, 9, 13, 8, 7, 6,
-}
-
-// findLSBSetNonZero64 returns the index (between 0 and 63) of the least
-// significant set bit. Passing zero to this function returns zero.
-//
-// This code comes from trailingZeroBits in https://golang.org/src/math/big/nat.go
-// which references (Knuth, volume 4, section 7.3.1).
-func findLSBSetNonZero64(x uint64) int {
- return int(deBruijn64Lookup[((x&-x)*(deBruijn64&digitMask))>>58])
-}