diff options
Diffstat (limited to 'vendor/github.com/ugorji/go/codec/helper_internal.go')
| -rw-r--r-- | vendor/github.com/ugorji/go/codec/helper_internal.go | 147 |
1 files changed, 0 insertions, 147 deletions
diff --git a/vendor/github.com/ugorji/go/codec/helper_internal.go b/vendor/github.com/ugorji/go/codec/helper_internal.go deleted file mode 100644 index e646249c7..000000000 --- a/vendor/github.com/ugorji/go/codec/helper_internal.go +++ /dev/null @@ -1,147 +0,0 @@ -// Copyright (c) 2012-2020 Ugorji Nwoke. All rights reserved. -// Use of this source code is governed by a MIT license found in the LICENSE file. - -package codec - -// maxArrayLen is the size of uint, which determines -// the maximum length of any array. -const maxArrayLen = 1<<((32<<(^uint(0)>>63))-1) - 1 - -// All non-std package dependencies live in this file, -// so porting to different environment is easy (just update functions). - -func pruneSignExt(v []byte, pos bool) (n int) { - if len(v) < 2 { - } else if pos && v[0] == 0 { - for ; v[n] == 0 && n+1 < len(v) && (v[n+1]&(1<<7) == 0); n++ { - } - } else if !pos && v[0] == 0xff { - for ; v[n] == 0xff && n+1 < len(v) && (v[n+1]&(1<<7) != 0); n++ { - } - } - return -} - -func halfFloatToFloatBits(h uint16) (f uint32) { - // retrofitted from: - // - OGRE (Object-Oriented Graphics Rendering Engine) - // function: halfToFloatI https://www.ogre3d.org/docs/api/1.9/_ogre_bitwise_8h_source.html - - s := uint32(h >> 15) - m := uint32(h & 0x03ff) - e := int32((h >> 10) & 0x1f) - - if e == 0 { - if m == 0 { // plus or minus 0 - return s << 31 - } - // Denormalized number -- renormalize it - for (m & 0x0400) == 0 { - m <<= 1 - e -= 1 - } - e += 1 - m &= ^uint32(0x0400) - } else if e == 31 { - if m == 0 { // Inf - return (s << 31) | 0x7f800000 - } - return (s << 31) | 0x7f800000 | (m << 13) // NaN - } - e = e + (127 - 15) - m = m << 13 - return (s << 31) | (uint32(e) << 23) | m -} - -func floatToHalfFloatBits(i uint32) (h uint16) { - // retrofitted from: - // - OGRE (Object-Oriented Graphics Rendering Engine) - // function: halfToFloatI https://www.ogre3d.org/docs/api/1.9/_ogre_bitwise_8h_source.html - // - http://www.java2s.com/example/java-utility-method/float-to/floattohalf-float-f-fae00.html - s := (i >> 16) & 0x8000 - e := int32(((i >> 23) & 0xff) - (127 - 15)) - m := i & 0x7fffff - - var h32 uint32 - - if e <= 0 { - if e < -10 { // zero - h32 = s // track -0 vs +0 - } else { - m = (m | 0x800000) >> uint32(1-e) - h32 = s | (m >> 13) - } - } else if e == 0xff-(127-15) { - if m == 0 { // Inf - h32 = s | 0x7c00 - } else { // NAN - m >>= 13 - var me uint32 - if m == 0 { - me = 1 - } - h32 = s | 0x7c00 | m | me - } - } else { - if e > 30 { // Overflow - h32 = s | 0x7c00 - } else { - h32 = s | (uint32(e) << 10) | (m >> 13) - } - } - h = uint16(h32) - return -} - -// growCap will return a new capacity for a slice, given the following: -// - oldCap: current capacity -// - unit: in-memory size of an element -// - num: number of elements to add -func growCap(oldCap, unit, num uint) (newCap uint) { - // appendslice logic (if cap < 1024, *2, else *1.25): - // leads to many copy calls, especially when copying bytes. - // bytes.Buffer model (2*cap + n): much better for bytes. - // smarter way is to take the byte-size of the appended element(type) into account - - // maintain 1 thresholds: - // t1: if cap <= t1, newcap = 2x - // else newcap = 1.5x - // - // t1 is always >= 1024. - // This means that, if unit size >= 16, then always do 2x or 1.5x (ie t1, t2, t3 are all same) - // - // With this, appending for bytes increase by: - // 100% up to 4K - // 50% beyond that - - // unit can be 0 e.g. for struct{}{}; handle that appropriately - maxCap := num + (oldCap * 3 / 2) - if unit == 0 || maxCap > maxArrayLen || maxCap < oldCap { // handle wraparound, etc - return maxArrayLen - } - - var t1 uint = 1024 // default thresholds for large values - if unit <= 4 { - t1 = 8 * 1024 - } else if unit <= 16 { - t1 = 2 * 1024 - } - - newCap = 2 + num - if oldCap > 0 { - if oldCap <= t1 { // [0,t1] - newCap = num + (oldCap * 2) - } else { // (t1,infinity] - newCap = maxCap - } - } - - // ensure newCap takes multiples of a cache line (size is a multiple of 64) - t1 = newCap * unit - if t2 := t1 % 64; t2 != 0 { - t1 += 64 - t2 - newCap = t1 / unit - } - - return -} |