githaven/vendor/github.com/minio/md5-simd/md5-util_amd64.go
2021-02-28 18:08:33 -05:00

86 lines
2.0 KiB
Go
Vendored

//+build !noasm,!appengine,gc
// Copyright (c) 2020 MinIO Inc. All rights reserved.
// Use of this source code is governed by a license that can be
// found in the LICENSE file.
package md5simd
// Helper struct for sorting blocks based on length
type lane struct {
len uint
pos uint
}
type digest struct {
s [4]uint32
}
// Helper struct for generating number of rounds in combination with mask for valid lanes
type maskRounds struct {
mask uint64
rounds uint64
}
func generateMaskAndRounds8(input [8][]byte, mr *[8]maskRounds) (rounds int) {
// Sort on blocks length small to large
var sorted [8]lane
for c, inpt := range input[:] {
sorted[c] = lane{uint(len(inpt)), uint(c)}
for i := c - 1; i >= 0; i-- {
// swap so largest is at the end...
if sorted[i].len > sorted[i+1].len {
sorted[i], sorted[i+1] = sorted[i+1], sorted[i]
continue
}
break
}
}
// Create mask array including 'rounds' (of processing blocks of 64 bytes) between masks
m, round := uint64(0xff), uint64(0)
for _, s := range sorted[:] {
if s.len > 0 {
if uint64(s.len)>>6 > round {
mr[rounds] = maskRounds{m, (uint64(s.len) >> 6) - round}
rounds++
}
round = uint64(s.len) >> 6
}
m = m & ^(1 << uint(s.pos))
}
return
}
func generateMaskAndRounds16(input [16][]byte, mr *[16]maskRounds) (rounds int) {
// Sort on blocks length small to large
var sorted [16]lane
for c, inpt := range input[:] {
sorted[c] = lane{uint(len(inpt)), uint(c)}
for i := c - 1; i >= 0; i-- {
// swap so largest is at the end...
if sorted[i].len > sorted[i+1].len {
sorted[i], sorted[i+1] = sorted[i+1], sorted[i]
continue
}
break
}
}
// Create mask array including 'rounds' (of processing blocks of 64 bytes) between masks
m, round := uint64(0xffff), uint64(0)
for _, s := range sorted[:] {
if s.len > 0 {
if uint64(s.len)>>6 > round {
mr[rounds] = maskRounds{m, (uint64(s.len) >> 6) - round}
rounds++
}
round = uint64(s.len) >> 6
}
m = m & ^(1 << uint(s.pos))
}
return
}