c2047754c3
Compiler changes:
* Change map assignment to use mapassign and assign value directly.
* Change string iteration to use decoderune, faster for ASCII strings.
* Change makeslice to take int, and use makeslice64 for larger values.
* Add new noverflow field to hmap struct used for maps.
Unresolved problems, to be fixed later:
* Commented out test in go/types/sizes_test.go that doesn't compile.
* Commented out reflect.TestStructOf test for padding after zero-sized field.
Reviewed-on: https://go-review.googlesource.com/35231
gotools/:
Updates for Go 1.8rc1.
* Makefile.am (go_cmd_go_files): Add bug.go.
(s-zdefaultcc): Write defaultPkgConfig.
* Makefile.in: Rebuild.
From-SVN: r244456
48 lines
971 B
Go
48 lines
971 B
Go
// Copyright 2015 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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// -build !amd64,!s390x
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package strings
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// TODO: implements short string optimization on non amd64 platforms
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// and get rid of strings_amd64.go
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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 string) int {
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n := len(sep)
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switch {
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case n == 0:
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return 0
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case n == 1:
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return IndexByte(s, sep[0])
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case n == len(s):
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if sep == s {
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return 0
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}
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return -1
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case n > len(s):
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return -1
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}
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// Rabin-Karp search
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hashsep, pow := hashStr(sep)
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var h uint32
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for i := 0; i < n; i++ {
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h = h*primeRK + uint32(s[i])
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}
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if h == hashsep && s[:n] == sep {
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return 0
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}
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for i := n; i < len(s); {
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h *= primeRK
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h += uint32(s[i])
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h -= pow * uint32(s[i-n])
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i++
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if h == hashsep && s[i-n:i] == sep {
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return i - n
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}
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}
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return -1
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}
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