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-rw-r--r--src/dma/vendor/golang.org/x/text/unicode/norm/triegen.go117
1 files changed, 117 insertions, 0 deletions
diff --git a/src/dma/vendor/golang.org/x/text/unicode/norm/triegen.go b/src/dma/vendor/golang.org/x/text/unicode/norm/triegen.go
new file mode 100644
index 00000000..45d71190
--- /dev/null
+++ b/src/dma/vendor/golang.org/x/text/unicode/norm/triegen.go
@@ -0,0 +1,117 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+// Trie table generator.
+// Used by make*tables tools to generate a go file with trie data structures
+// for mapping UTF-8 to a 16-bit value. All but the last byte in a UTF-8 byte
+// sequence are used to lookup offsets in the index table to be used for the
+// next byte. The last byte is used to index into a table with 16-bit values.
+
+package main
+
+import (
+ "fmt"
+ "io"
+)
+
+const maxSparseEntries = 16
+
+type normCompacter struct {
+ sparseBlocks [][]uint64
+ sparseOffset []uint16
+ sparseCount int
+ name string
+}
+
+func mostFrequentStride(a []uint64) int {
+ counts := make(map[int]int)
+ var v int
+ for _, x := range a {
+ if stride := int(x) - v; v != 0 && stride >= 0 {
+ counts[stride]++
+ }
+ v = int(x)
+ }
+ var maxs, maxc int
+ for stride, cnt := range counts {
+ if cnt > maxc || (cnt == maxc && stride < maxs) {
+ maxs, maxc = stride, cnt
+ }
+ }
+ return maxs
+}
+
+func countSparseEntries(a []uint64) int {
+ stride := mostFrequentStride(a)
+ var v, count int
+ for _, tv := range a {
+ if int(tv)-v != stride {
+ if tv != 0 {
+ count++
+ }
+ }
+ v = int(tv)
+ }
+ return count
+}
+
+func (c *normCompacter) Size(v []uint64) (sz int, ok bool) {
+ if n := countSparseEntries(v); n <= maxSparseEntries {
+ return (n+1)*4 + 2, true
+ }
+ return 0, false
+}
+
+func (c *normCompacter) Store(v []uint64) uint32 {
+ h := uint32(len(c.sparseOffset))
+ c.sparseBlocks = append(c.sparseBlocks, v)
+ c.sparseOffset = append(c.sparseOffset, uint16(c.sparseCount))
+ c.sparseCount += countSparseEntries(v) + 1
+ return h
+}
+
+func (c *normCompacter) Handler() string {
+ return c.name + "Sparse.lookup"
+}
+
+func (c *normCompacter) Print(w io.Writer) (retErr error) {
+ p := func(f string, x ...interface{}) {
+ if _, err := fmt.Fprintf(w, f, x...); retErr == nil && err != nil {
+ retErr = err
+ }
+ }
+
+ ls := len(c.sparseBlocks)
+ p("// %sSparseOffset: %d entries, %d bytes\n", c.name, ls, ls*2)
+ p("var %sSparseOffset = %#v\n\n", c.name, c.sparseOffset)
+
+ ns := c.sparseCount
+ p("// %sSparseValues: %d entries, %d bytes\n", c.name, ns, ns*4)
+ p("var %sSparseValues = [%d]valueRange {", c.name, ns)
+ for i, b := range c.sparseBlocks {
+ p("\n// Block %#x, offset %#x", i, c.sparseOffset[i])
+ var v int
+ stride := mostFrequentStride(b)
+ n := countSparseEntries(b)
+ p("\n{value:%#04x,lo:%#02x},", stride, uint8(n))
+ for i, nv := range b {
+ if int(nv)-v != stride {
+ if v != 0 {
+ p(",hi:%#02x},", 0x80+i-1)
+ }
+ if nv != 0 {
+ p("\n{value:%#04x,lo:%#02x", nv, 0x80+i)
+ }
+ }
+ v = int(nv)
+ }
+ if v != 0 {
+ p(",hi:%#02x},", 0x80+len(b)-1)
+ }
+ }
+ p("\n}\n\n")
+ return
+}