Add Go frontend, libgo library, and Go testsuite.
gcc/: * gcc.c (default_compilers): Add entry for ".go". * common.opt: Add -static-libgo as a driver option. * doc/install.texi (Configuration): Mention libgo as an option for --enable-shared. Mention go as an option for --enable-languages. * doc/invoke.texi (Overall Options): Mention .go as a file name suffix. Mention go as a -x option. * doc/frontends.texi (G++ and GCC): Mention Go as a supported language. * doc/sourcebuild.texi (Top Level): Mention libgo. * doc/standards.texi (Standards): Add section on Go language. Move references for other languages into their own section. * doc/contrib.texi (Contributors): Mention that I contributed the Go frontend. gcc/testsuite/: * lib/go.exp: New file. * lib/go-dg.exp: New file. * lib/go-torture.exp: New file. * lib/target-supports.exp (check_compile): Match // Go. From-SVN: r167407
This commit is contained in:
Ian Lance Taylor
parent
1aa6700378
commit
7a9389330e
1565 changed files with 351565 additions and 12 deletions
625
libgo/go/bytes/bytes.go
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625
libgo/go/bytes/bytes.go
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@ -0,0 +1,625 @@
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// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// The bytes package implements functions for the manipulation of byte slices.
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// Analogous to the facilities of the strings package.
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package bytes
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import (
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"unicode"
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"utf8"
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)
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// Compare returns an integer comparing the two byte arrays lexicographically.
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// The result will be 0 if a==b, -1 if a < b, and +1 if a > b
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func Compare(a, b []byte) int {
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m := len(a)
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if m > len(b) {
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m = len(b)
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}
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for i, ac := range a[0:m] {
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bc := b[i]
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switch {
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case ac > bc:
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return 1
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case ac < bc:
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return -1
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}
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}
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switch {
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case len(a) < len(b):
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return -1
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case len(a) > len(b):
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return 1
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}
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return 0
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}
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// Equal returns a boolean reporting whether a == b.
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func Equal(a, b []byte) bool {
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if len(a) != len(b) {
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return false
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}
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for i, c := range a {
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if c != b[i] {
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return false
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}
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}
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return true
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}
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// explode splits s into an array of UTF-8 sequences, one per Unicode character (still arrays of bytes),
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// up to a maximum of n byte arrays. Invalid UTF-8 sequences are chopped into individual bytes.
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func explode(s []byte, n int) [][]byte {
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if n <= 0 {
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n = len(s)
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}
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a := make([][]byte, n)
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var size int
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na := 0
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for len(s) > 0 {
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if na+1 >= n {
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a[na] = s
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na++
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break
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}
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_, size = utf8.DecodeRune(s)
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a[na] = s[0:size]
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s = s[size:]
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na++
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}
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return a[0:na]
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}
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// Count counts the number of non-overlapping instances of sep in s.
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func Count(s, sep []byte) int {
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if len(sep) == 0 {
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return utf8.RuneCount(s) + 1
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}
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c := sep[0]
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n := 0
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for i := 0; i+len(sep) <= len(s); i++ {
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if s[i] == c && (len(sep) == 1 || Equal(s[i:i+len(sep)], sep)) {
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n++
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i += len(sep) - 1
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}
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}
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return n
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}
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// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
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func Index(s, sep []byte) int {
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n := len(sep)
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if n == 0 {
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return 0
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}
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c := sep[0]
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for i := 0; i+n <= len(s); i++ {
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if s[i] == c && (n == 1 || Equal(s[i:i+n], sep)) {
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return i
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}
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}
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return -1
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}
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func indexBytePortable(s []byte, c byte) int {
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for i, b := range s {
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if b == c {
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return i
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}
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}
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return -1
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}
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// LastIndex returns the index of the last instance of sep in s, or -1 if sep is not present in s.
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func LastIndex(s, sep []byte) int {
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n := len(sep)
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if n == 0 {
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return len(s)
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}
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c := sep[0]
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for i := len(s) - n; i >= 0; i-- {
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if s[i] == c && (n == 1 || Equal(s[i:i+n], sep)) {
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return i
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}
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}
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return -1
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}
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// IndexRune interprets s as a sequence of UTF-8-encoded Unicode code points.
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// It returns the byte index of the first occurrence in s of the given rune.
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// It returns -1 if rune is not present in s.
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func IndexRune(s []byte, rune int) int {
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for i := 0; i < len(s); {
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r, size := utf8.DecodeRune(s[i:])
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if r == rune {
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return i
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}
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i += size
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}
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return -1
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}
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// IndexAny interprets s as a sequence of UTF-8-encoded Unicode code points.
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// It returns the byte index of the first occurrence in s of any of the Unicode
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// code points in chars. It returns -1 if chars is empty or if there is no code
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// point in common.
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func IndexAny(s []byte, chars string) int {
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if len(chars) > 0 {
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var rune, width int
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for i := 0; i < len(s); i += width {
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rune = int(s[i])
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if rune < utf8.RuneSelf {
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width = 1
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} else {
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rune, width = utf8.DecodeRune(s[i:])
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}
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for _, r := range chars {
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if rune == r {
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return i
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}
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}
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}
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}
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return -1
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}
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// Generic split: splits after each instance of sep,
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// including sepSave bytes of sep in the subarrays.
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func genSplit(s, sep []byte, sepSave, n int) [][]byte {
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if n == 0 {
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return nil
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}
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if len(sep) == 0 {
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return explode(s, n)
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}
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if n < 0 {
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n = Count(s, sep) + 1
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}
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c := sep[0]
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start := 0
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a := make([][]byte, n)
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na := 0
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for i := 0; i+len(sep) <= len(s) && na+1 < n; i++ {
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if s[i] == c && (len(sep) == 1 || Equal(s[i:i+len(sep)], sep)) {
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a[na] = s[start : i+sepSave]
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na++
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start = i + len(sep)
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i += len(sep) - 1
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}
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}
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a[na] = s[start:]
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return a[0 : na+1]
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}
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// Split slices s into subslices separated by sep and returns a slice of
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// the subslices between those separators.
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// If sep is empty, Split splits after each UTF-8 sequence.
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// The count determines the number of subslices to return:
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// n > 0: at most n subslices; the last subslice will be the unsplit remainder.
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// n == 0: the result is nil (zero subslices)
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// n < 0: all subslices
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func Split(s, sep []byte, n int) [][]byte { return genSplit(s, sep, 0, n) }
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// SplitAfter slices s into subslices after each instance of sep and
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// returns a slice of those subslices.
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// If sep is empty, Split splits after each UTF-8 sequence.
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// The count determines the number of subslices to return:
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// n > 0: at most n subslices; the last subslice will be the unsplit remainder.
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// n == 0: the result is nil (zero subslices)
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// n < 0: all subslices
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func SplitAfter(s, sep []byte, n int) [][]byte {
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return genSplit(s, sep, len(sep), n)
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}
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// Fields splits the array s around each instance of one or more consecutive white space
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// characters, returning a slice of subarrays of s or an empty list if s contains only white space.
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func Fields(s []byte) [][]byte {
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return FieldsFunc(s, unicode.IsSpace)
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}
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// FieldsFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
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// It splits the array s at each run of code points c satisfying f(c) and
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// returns a slice of subarrays of s. If no code points in s satisfy f(c), an
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// empty slice is returned.
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func FieldsFunc(s []byte, f func(int) bool) [][]byte {
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n := 0
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inField := false
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for i := 0; i < len(s); {
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rune, size := utf8.DecodeRune(s[i:])
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wasInField := inField
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inField = !f(rune)
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if inField && !wasInField {
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n++
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}
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i += size
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}
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a := make([][]byte, n)
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na := 0
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fieldStart := -1
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for i := 0; i <= len(s) && na < n; {
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rune, size := utf8.DecodeRune(s[i:])
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if fieldStart < 0 && size > 0 && !f(rune) {
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fieldStart = i
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i += size
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continue
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}
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if fieldStart >= 0 && (size == 0 || f(rune)) {
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a[na] = s[fieldStart:i]
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na++
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fieldStart = -1
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}
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if size == 0 {
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break
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}
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i += size
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}
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return a[0:na]
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}
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// Join concatenates the elements of a to create a single byte array. The separator
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// sep is placed between elements in the resulting array.
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func Join(a [][]byte, sep []byte) []byte {
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if len(a) == 0 {
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return []byte{}
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}
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if len(a) == 1 {
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return a[0]
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}
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n := len(sep) * (len(a) - 1)
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for i := 0; i < len(a); i++ {
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n += len(a[i])
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}
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b := make([]byte, n)
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bp := 0
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for i := 0; i < len(a); i++ {
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s := a[i]
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for j := 0; j < len(s); j++ {
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b[bp] = s[j]
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bp++
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}
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if i+1 < len(a) {
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s = sep
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for j := 0; j < len(s); j++ {
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b[bp] = s[j]
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bp++
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}
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}
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}
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return b
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}
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// HasPrefix tests whether the byte array s begins with prefix.
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func HasPrefix(s, prefix []byte) bool {
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return len(s) >= len(prefix) && Equal(s[0:len(prefix)], prefix)
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}
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// HasSuffix tests whether the byte array s ends with suffix.
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func HasSuffix(s, suffix []byte) bool {
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return len(s) >= len(suffix) && Equal(s[len(s)-len(suffix):], suffix)
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}
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// Map returns a copy of the byte array s with all its characters modified
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// according to the mapping function. If mapping returns a negative value, the character is
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// dropped from the string with no replacement. The characters in s and the
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// output are interpreted as UTF-8-encoded Unicode code points.
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func Map(mapping func(rune int) int, s []byte) []byte {
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// In the worst case, the array can grow when mapped, making
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// things unpleasant. But it's so rare we barge in assuming it's
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// fine. It could also shrink but that falls out naturally.
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maxbytes := len(s) // length of b
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nbytes := 0 // number of bytes encoded in b
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b := make([]byte, maxbytes)
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for i := 0; i < len(s); {
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wid := 1
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rune := int(s[i])
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if rune >= utf8.RuneSelf {
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rune, wid = utf8.DecodeRune(s[i:])
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}
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rune = mapping(rune)
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if rune >= 0 {
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if nbytes+utf8.RuneLen(rune) > maxbytes {
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// Grow the buffer.
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maxbytes = maxbytes*2 + utf8.UTFMax
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nb := make([]byte, maxbytes)
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copy(nb, b[0:nbytes])
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b = nb
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}
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nbytes += utf8.EncodeRune(rune, b[nbytes:maxbytes])
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}
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i += wid
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}
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return b[0:nbytes]
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}
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// Repeat returns a new byte slice consisting of count copies of b.
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func Repeat(b []byte, count int) []byte {
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nb := make([]byte, len(b)*count)
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bp := 0
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for i := 0; i < count; i++ {
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for j := 0; j < len(b); j++ {
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nb[bp] = b[j]
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bp++
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}
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}
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return nb
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}
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// ToUpper returns a copy of the byte array s with all Unicode letters mapped to their upper case.
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func ToUpper(s []byte) []byte { return Map(unicode.ToUpper, s) }
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// ToUpper returns a copy of the byte array s with all Unicode letters mapped to their lower case.
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func ToLower(s []byte) []byte { return Map(unicode.ToLower, s) }
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// ToTitle returns a copy of the byte array s with all Unicode letters mapped to their title case.
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func ToTitle(s []byte) []byte { return Map(unicode.ToTitle, s) }
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// ToUpperSpecial returns a copy of the byte array s with all Unicode letters mapped to their
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// upper case, giving priority to the special casing rules.
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func ToUpperSpecial(_case unicode.SpecialCase, s []byte) []byte {
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return Map(func(r int) int { return _case.ToUpper(r) }, s)
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}
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// ToLowerSpecial returns a copy of the byte array s with all Unicode letters mapped to their
|
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// lower case, giving priority to the special casing rules.
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func ToLowerSpecial(_case unicode.SpecialCase, s []byte) []byte {
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return Map(func(r int) int { return _case.ToLower(r) }, s)
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}
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// ToTitleSpecial returns a copy of the byte array s with all Unicode letters mapped to their
|
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// title case, giving priority to the special casing rules.
|
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func ToTitleSpecial(_case unicode.SpecialCase, s []byte) []byte {
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return Map(func(r int) int { return _case.ToTitle(r) }, s)
|
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}
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|
||||
|
||||
// isSeparator reports whether the rune could mark a word boundary.
|
||||
// TODO: update when package unicode captures more of the properties.
|
||||
func isSeparator(rune int) bool {
|
||||
// ASCII alphanumerics and underscore are not separators
|
||||
if rune <= 0x7F {
|
||||
switch {
|
||||
case '0' <= rune && rune <= '9':
|
||||
return false
|
||||
case 'a' <= rune && rune <= 'z':
|
||||
return false
|
||||
case 'A' <= rune && rune <= 'Z':
|
||||
return false
|
||||
case rune == '_':
|
||||
return false
|
||||
}
|
||||
return true
|
||||
}
|
||||
// Letters and digits are not separators
|
||||
if unicode.IsLetter(rune) || unicode.IsDigit(rune) {
|
||||
return false
|
||||
}
|
||||
// Otherwise, all we can do for now is treat spaces as separators.
|
||||
return unicode.IsSpace(rune)
|
||||
}
|
||||
|
||||
// BUG(r): The rule Title uses for word boundaries does not handle Unicode punctuation properly.
|
||||
|
||||
// Title returns a copy of s with all Unicode letters that begin words
|
||||
// mapped to their title case.
|
||||
func Title(s []byte) []byte {
|
||||
// Use a closure here to remember state.
|
||||
// Hackish but effective. Depends on Map scanning in order and calling
|
||||
// the closure once per rune.
|
||||
prev := ' '
|
||||
return Map(
|
||||
func(r int) int {
|
||||
if isSeparator(prev) {
|
||||
prev = r
|
||||
return unicode.ToTitle(r)
|
||||
}
|
||||
prev = r
|
||||
return r
|
||||
},
|
||||
s)
|
||||
}
|
||||
|
||||
// TrimLeftFunc returns a subslice of s by slicing off all leading UTF-8-encoded
|
||||
// Unicode code points c that satisfy f(c).
|
||||
func TrimLeftFunc(s []byte, f func(r int) bool) []byte {
|
||||
i := indexFunc(s, f, false)
|
||||
if i == -1 {
|
||||
return nil
|
||||
}
|
||||
return s[i:]
|
||||
}
|
||||
|
||||
// TrimRightFunc returns a subslice of s by slicing off all trailing UTF-8
|
||||
// encoded Unicode code points c that satisfy f(c).
|
||||
func TrimRightFunc(s []byte, f func(r int) bool) []byte {
|
||||
i := lastIndexFunc(s, f, false)
|
||||
if i >= 0 && s[i] >= utf8.RuneSelf {
|
||||
_, wid := utf8.DecodeRune(s[i:])
|
||||
i += wid
|
||||
} else {
|
||||
i++
|
||||
}
|
||||
return s[0:i]
|
||||
}
|
||||
|
||||
// TrimFunc returns a subslice of s by slicing off all leading and trailing
|
||||
// UTF-8-encoded Unicode code points c that satisfy f(c).
|
||||
func TrimFunc(s []byte, f func(r int) bool) []byte {
|
||||
return TrimRightFunc(TrimLeftFunc(s, f), f)
|
||||
}
|
||||
|
||||
// IndexFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
|
||||
// It returns the byte index in s of the first Unicode
|
||||
// code point satisfying f(c), or -1 if none do.
|
||||
func IndexFunc(s []byte, f func(r int) bool) int {
|
||||
return indexFunc(s, f, true)
|
||||
}
|
||||
|
||||
// LastIndexFunc interprets s as a sequence of UTF-8-encoded Unicode code points.
|
||||
// It returns the byte index in s of the last Unicode
|
||||
// code point satisfying f(c), or -1 if none do.
|
||||
func LastIndexFunc(s []byte, f func(r int) bool) int {
|
||||
return lastIndexFunc(s, f, true)
|
||||
}
|
||||
|
||||
// indexFunc is the same as IndexFunc except that if
|
||||
// truth==false, the sense of the predicate function is
|
||||
// inverted.
|
||||
func indexFunc(s []byte, f func(r int) bool, truth bool) int {
|
||||
start := 0
|
||||
for start < len(s) {
|
||||
wid := 1
|
||||
rune := int(s[start])
|
||||
if rune >= utf8.RuneSelf {
|
||||
rune, wid = utf8.DecodeRune(s[start:])
|
||||
}
|
||||
if f(rune) == truth {
|
||||
return start
|
||||
}
|
||||
start += wid
|
||||
}
|
||||
return -1
|
||||
}
|
||||
|
||||
// lastIndexFunc is the same as LastIndexFunc except that if
|
||||
// truth==false, the sense of the predicate function is
|
||||
// inverted.
|
||||
func lastIndexFunc(s []byte, f func(r int) bool, truth bool) int {
|
||||
for i := len(s); i > 0; {
|
||||
rune, size := utf8.DecodeLastRune(s[0:i])
|
||||
i -= size
|
||||
if f(rune) == truth {
|
||||
return i
|
||||
}
|
||||
}
|
||||
return -1
|
||||
}
|
||||
|
||||
func makeCutsetFunc(cutset string) func(rune int) bool {
|
||||
return func(rune int) bool {
|
||||
for _, c := range cutset {
|
||||
if c == rune {
|
||||
return true
|
||||
}
|
||||
}
|
||||
return false
|
||||
}
|
||||
}
|
||||
|
||||
// Trim returns a subslice of s by slicing off all leading and
|
||||
// trailing UTF-8-encoded Unicode code points contained in cutset.
|
||||
func Trim(s []byte, cutset string) []byte {
|
||||
return TrimFunc(s, makeCutsetFunc(cutset))
|
||||
}
|
||||
|
||||
// TrimLeft returns a subslice of s by slicing off all leading
|
||||
// UTF-8-encoded Unicode code points contained in cutset.
|
||||
func TrimLeft(s []byte, cutset string) []byte {
|
||||
return TrimLeftFunc(s, makeCutsetFunc(cutset))
|
||||
}
|
||||
|
||||
// TrimRight returns a subslice of s by slicing off all trailing
|
||||
// UTF-8-encoded Unicode code points that are contained in cutset.
|
||||
func TrimRight(s []byte, cutset string) []byte {
|
||||
return TrimRightFunc(s, makeCutsetFunc(cutset))
|
||||
}
|
||||
|
||||
// TrimSpace returns a subslice of s by slicing off all leading and
|
||||
// trailing white space, as as defined by Unicode.
|
||||
func TrimSpace(s []byte) []byte {
|
||||
return TrimFunc(s, unicode.IsSpace)
|
||||
}
|
||||
|
||||
// How big to make a byte array when growing.
|
||||
// Heuristic: Scale by 50% to give n log n time.
|
||||
func resize(n int) int {
|
||||
if n < 16 {
|
||||
n = 16
|
||||
}
|
||||
return n + n/2
|
||||
}
|
||||
|
||||
// Add appends the contents of t to the end of s and returns the result.
|
||||
// If s has enough capacity, it is extended in place; otherwise a
|
||||
// new array is allocated and returned.
|
||||
func Add(s, t []byte) []byte { // TODO
|
||||
lens := len(s)
|
||||
lent := len(t)
|
||||
if lens+lent <= cap(s) {
|
||||
s = s[0 : lens+lent]
|
||||
} else {
|
||||
news := make([]byte, lens+lent, resize(lens+lent))
|
||||
copy(news, s)
|
||||
s = news
|
||||
}
|
||||
copy(s[lens:lens+lent], t)
|
||||
return s
|
||||
}
|
||||
|
||||
// AddByte appends byte t to the end of s and returns the result.
|
||||
// If s has enough capacity, it is extended in place; otherwise a
|
||||
// new array is allocated and returned.
|
||||
func AddByte(s []byte, t byte) []byte { // TODO
|
||||
lens := len(s)
|
||||
if lens+1 <= cap(s) {
|
||||
s = s[0 : lens+1]
|
||||
} else {
|
||||
news := make([]byte, lens+1, resize(lens+1))
|
||||
copy(news, s)
|
||||
s = news
|
||||
}
|
||||
s[lens] = t
|
||||
return s
|
||||
}
|
||||
|
||||
// Runes returns a slice of runes (Unicode code points) equivalent to s.
|
||||
func Runes(s []byte) []int {
|
||||
t := make([]int, utf8.RuneCount(s))
|
||||
i := 0
|
||||
for len(s) > 0 {
|
||||
r, l := utf8.DecodeRune(s)
|
||||
t[i] = r
|
||||
i++
|
||||
s = s[l:]
|
||||
}
|
||||
return t
|
||||
}
|
||||
|
||||
// Replace returns a copy of the slice s with the first n
|
||||
// non-overlapping instances of old replaced by new.
|
||||
// If n < 0, there is no limit on the number of replacements.
|
||||
func Replace(s, old, new []byte, n int) []byte {
|
||||
if n == 0 {
|
||||
return s // avoid allocation
|
||||
}
|
||||
// Compute number of replacements.
|
||||
if m := Count(s, old); m == 0 {
|
||||
return s // avoid allocation
|
||||
} else if n <= 0 || m < n {
|
||||
n = m
|
||||
}
|
||||
|
||||
// Apply replacements to buffer.
|
||||
t := make([]byte, len(s)+n*(len(new)-len(old)))
|
||||
w := 0
|
||||
start := 0
|
||||
for i := 0; i < n; i++ {
|
||||
j := start
|
||||
if len(old) == 0 {
|
||||
if i > 0 {
|
||||
_, wid := utf8.DecodeRune(s[start:])
|
||||
j += wid
|
||||
}
|
||||
} else {
|
||||
j += Index(s[start:], old)
|
||||
}
|
||||
w += copy(t[w:], s[start:j])
|
||||
w += copy(t[w:], new)
|
||||
start = j + len(old)
|
||||
}
|
||||
w += copy(t[w:], s[start:])
|
||||
return t[0:w]
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue