7a9389330e
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
51 lines
897 B
Go
51 lines
897 B
Go
// 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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package math
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/*
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Floating-point arcsine and arccosine.
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They are implemented by computing the arctangent
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after appropriate range reduction.
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*/
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// Asin returns the arcsine of x.
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//
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// Special cases are:
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// Asin(±0) = ±0
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// Asin(x) = NaN if x < -1 or x > 1
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func Asin(x float64) float64 {
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if x == 0 {
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return x // special case
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}
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sign := false
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if x < 0 {
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x = -x
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sign = true
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}
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if x > 1 {
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return NaN() // special case
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}
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temp := Sqrt(1 - x*x)
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if x > 0.7 {
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temp = Pi/2 - satan(temp/x)
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} else {
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temp = satan(x / temp)
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}
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if sign {
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temp = -temp
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}
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return temp
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}
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// Acos returns the arccosine of x.
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//
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// Special case is:
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// Acos(x) = NaN if x < -1 or x > 1
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func Acos(x float64) float64 { return Pi/2 - Asin(x) }
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