Adding upstream version 1.18.10.upstream/1.18.10upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 198 insertions, 0 deletions

diff --git a/src/runtime/softfloat64_test.go b/src/runtime/softfloat64_test.go
new file mode 100644
index 0000000..3f53e8b
--- /dev/null
+++ b/src/runtime/softfloat64_test.go
@@ -0,0 +1,198 @@
+// Copyright 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 runtime_test
+
+import (
+	"math"
+	"math/rand"
+	. "runtime"
+	"testing"
+)
+
+// turn uint64 op into float64 op
+func fop(f func(x, y uint64) uint64) func(x, y float64) float64 {
+	return func(x, y float64) float64 {
+		bx := math.Float64bits(x)
+		by := math.Float64bits(y)
+		return math.Float64frombits(f(bx, by))
+	}
+}
+
+func add(x, y float64) float64 { return x + y }
+func sub(x, y float64) float64 { return x - y }
+func mul(x, y float64) float64 { return x * y }
+func div(x, y float64) float64 { return x / y }
+
+func TestFloat64(t *testing.T) {
+	base := []float64{
+		0,
+		math.Copysign(0, -1),
+		-1,
+		1,
+		math.NaN(),
+		math.Inf(+1),
+		math.Inf(-1),
+		0.1,
+		1.5,
+		1.9999999999999998,     // all 1s mantissa
+		1.3333333333333333,     // 1.010101010101...
+		1.1428571428571428,     // 1.001001001001...
+		1.112536929253601e-308, // first normal
+		2,
+		4,
+		8,
+		16,
+		32,
+		64,
+		128,
+		256,
+		3,
+		12,
+		1234,
+		123456,
+		-0.1,
+		-1.5,
+		-1.9999999999999998,
+		-1.3333333333333333,
+		-1.1428571428571428,
+		-2,
+		-3,
+		1e-200,
+		1e-300,
+		1e-310,
+		5e-324,
+		1e-105,
+		1e-305,
+		1e+200,
+		1e+306,
+		1e+307,
+		1e+308,
+	}
+	all := make([]float64, 200)
+	copy(all, base)
+	for i := len(base); i < len(all); i++ {
+		all[i] = rand.NormFloat64()
+	}
+
+	test(t, "+", add, fop(Fadd64), all)
+	test(t, "-", sub, fop(Fsub64), all)
+	if GOARCH != "386" { // 386 is not precise!
+		test(t, "*", mul, fop(Fmul64), all)
+		test(t, "/", div, fop(Fdiv64), all)
+	}
+}
+
+// 64 -hw-> 32 -hw-> 64
+func trunc32(f float64) float64 {
+	return float64(float32(f))
+}
+
+// 64 -sw->32 -hw-> 64
+func to32sw(f float64) float64 {
+	return float64(math.Float32frombits(F64to32(math.Float64bits(f))))
+}
+
+// 64 -hw->32 -sw-> 64
+func to64sw(f float64) float64 {
+	return math.Float64frombits(F32to64(math.Float32bits(float32(f))))
+}
+
+// float64 -hw-> int64 -hw-> float64
+func hwint64(f float64) float64 {
+	return float64(int64(f))
+}
+
+// float64 -hw-> int32 -hw-> float64
+func hwint32(f float64) float64 {
+	return float64(int32(f))
+}
+
+// float64 -sw-> int64 -hw-> float64
+func toint64sw(f float64) float64 {
+	i, ok := F64toint(math.Float64bits(f))
+	if !ok {
+		// There's no right answer for out of range.
+		// Match the hardware to pass the test.
+		i = int64(f)
+	}
+	return float64(i)
+}
+
+// float64 -hw-> int64 -sw-> float64
+func fromint64sw(f float64) float64 {
+	return math.Float64frombits(Fintto64(int64(f)))
+}
+
+var nerr int
+
+func err(t *testing.T, format string, args ...any) {
+	t.Errorf(format, args...)
+
+	// cut errors off after a while.
+	// otherwise we spend all our time
+	// allocating memory to hold the
+	// formatted output.
+	if nerr++; nerr >= 10 {
+		t.Fatal("too many errors")
+	}
+}
+
+func test(t *testing.T, op string, hw, sw func(float64, float64) float64, all []float64) {
+	for _, f := range all {
+		for _, g := range all {
+			h := hw(f, g)
+			s := sw(f, g)
+			if !same(h, s) {
+				err(t, "%g %s %g = sw %g, hw %g\n", f, op, g, s, h)
+			}
+			testu(t, "to32", trunc32, to32sw, h)
+			testu(t, "to64", trunc32, to64sw, h)
+			testu(t, "toint64", hwint64, toint64sw, h)
+			testu(t, "fromint64", hwint64, fromint64sw, h)
+			testcmp(t, f, h)
+			testcmp(t, h, f)
+			testcmp(t, g, h)
+			testcmp(t, h, g)
+		}
+	}
+}
+
+func testu(t *testing.T, op string, hw, sw func(float64) float64, v float64) {
+	h := hw(v)
+	s := sw(v)
+	if !same(h, s) {
+		err(t, "%s %g = sw %g, hw %g\n", op, v, s, h)
+	}
+}
+
+func hwcmp(f, g float64) (cmp int, isnan bool) {
+	switch {
+	case f < g:
+		return -1, false
+	case f > g:
+		return +1, false
+	case f == g:
+		return 0, false
+	}
+	return 0, true // must be NaN
+}
+
+func testcmp(t *testing.T, f, g float64) {
+	hcmp, hisnan := hwcmp(f, g)
+	scmp, sisnan := Fcmp64(math.Float64bits(f), math.Float64bits(g))
+	if int32(hcmp) != scmp || hisnan != sisnan {
+		err(t, "cmp(%g, %g) = sw %v, %v, hw %v, %v\n", f, g, scmp, sisnan, hcmp, hisnan)
+	}
+}
+
+func same(f, g float64) bool {
+	if math.IsNaN(f) && math.IsNaN(g) {
+		return true
+	}
+	if math.Copysign(1, f) != math.Copysign(1, g) {
+		return false
+	}
+	return f == g
+}