gcc/libgo/go/math/floor.go
Ian Lance Taylor 7a9389330e 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
2010-12-03 04:34:57 +00:00

54 lines
1.3 KiB
Go

// Copyright 2009-2010 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.
package math
// Floor returns the greatest integer value less than or equal to x.
//
// Special cases are:
// Floor(+Inf) = +Inf
// Floor(-Inf) = -Inf
// Floor(NaN) = NaN
func Floor(x float64) float64 {
// TODO(rsc): Remove manual inlining of IsNaN, IsInf
// when compiler does it for us
if x == 0 || x != x || x > MaxFloat64 || x < -MaxFloat64 { // x == 0 || IsNaN(x) || IsInf(x, 0)
return x
}
if x < 0 {
d, fract := Modf(-x)
if fract != 0.0 {
d = d + 1
}
return -d
}
d, _ := Modf(x)
return d
}
// Ceil returns the least integer value greater than or equal to x.
//
// Special cases are:
// Ceil(+Inf) = +Inf
// Ceil(-Inf) = -Inf
// Ceil(NaN) = NaN
func Ceil(x float64) float64 { return -Floor(-x) }
// Trunc returns the integer value of x.
//
// Special cases are:
// Trunc(+Inf) = +Inf
// Trunc(-Inf) = -Inf
// Trunc(NaN) = NaN
func Trunc(x float64) float64 {
// TODO(rsc): Remove manual inlining of IsNaN, IsInf
// when compiler does it for us
if x == 0 || x != x || x > MaxFloat64 || x < -MaxFloat64 { // x == 0 || IsNaN(x) || IsInf(x, 0)
return x
}
d, _ := Modf(x)
return d
}