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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
commit73df946d56c74384511a194dd01dbe099584fd1a (patch)
treefd0bcea490dd81327ddfbb31e215439672c9a068 /src/runtime/float.go
parentInitial commit. (diff)
downloadgolang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.tar.xz
golang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.zip
Adding upstream version 1.16.10.upstream/1.16.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/runtime/float.go')
-rw-r--r--src/runtime/float.go53
1 files changed, 53 insertions, 0 deletions
diff --git a/src/runtime/float.go b/src/runtime/float.go
new file mode 100644
index 0000000..459e58d
--- /dev/null
+++ b/src/runtime/float.go
@@ -0,0 +1,53 @@
+// Copyright 2017 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 runtime
+
+import "unsafe"
+
+var inf = float64frombits(0x7FF0000000000000)
+
+// isNaN reports whether f is an IEEE 754 ``not-a-number'' value.
+func isNaN(f float64) (is bool) {
+ // IEEE 754 says that only NaNs satisfy f != f.
+ return f != f
+}
+
+// isFinite reports whether f is neither NaN nor an infinity.
+func isFinite(f float64) bool {
+ return !isNaN(f - f)
+}
+
+// isInf reports whether f is an infinity.
+func isInf(f float64) bool {
+ return !isNaN(f) && !isFinite(f)
+}
+
+// Abs returns the absolute value of x.
+//
+// Special cases are:
+// Abs(±Inf) = +Inf
+// Abs(NaN) = NaN
+func abs(x float64) float64 {
+ const sign = 1 << 63
+ return float64frombits(float64bits(x) &^ sign)
+}
+
+// copysign returns a value with the magnitude
+// of x and the sign of y.
+func copysign(x, y float64) float64 {
+ const sign = 1 << 63
+ return float64frombits(float64bits(x)&^sign | float64bits(y)&sign)
+}
+
+// Float64bits returns the IEEE 754 binary representation of f.
+func float64bits(f float64) uint64 {
+ return *(*uint64)(unsafe.Pointer(&f))
+}
+
+// Float64frombits returns the floating point number corresponding
+// the IEEE 754 binary representation b.
+func float64frombits(b uint64) float64 {
+ return *(*float64)(unsafe.Pointer(&b))
+}