From ac8a97ac9e5de94d1c0e830299ce6487cbbfd3f6 Mon Sep 17 00:00:00 2001 From: Than McIntosh Date: Fri, 10 Feb 2023 14:39:20 +0000 Subject: [PATCH] Revert "math: add Compare and Compare32" This reverts CL 459435. Reason for revert: Tests failing on MIPS. Change-Id: I9017bf718ba938df6d6766041555034d55d90b8a Reviewed-on: https://go-review.googlesource.com/c/go/+/467255 Run-TryBot: Than McIntosh Reviewed-by: Than McIntosh Reviewed-by: Dmitri Shuralyov TryBot-Result: Gopher Robot Reviewed-by: Akhil Indurti Reviewed-by: Dmitri Shuralyov --- api/next/56491.txt | 2 -- src/math/all_test.go | 59 -------------------------------------------- src/math/compare.go | 53 --------------------------------------- 3 files changed, 114 deletions(-) delete mode 100644 api/next/56491.txt delete mode 100644 src/math/compare.go diff --git a/api/next/56491.txt b/api/next/56491.txt deleted file mode 100644 index 333f92e215..0000000000 --- a/api/next/56491.txt +++ /dev/null @@ -1,2 +0,0 @@ -pkg math, func Compare(float64, float64) int #56491 -pkg math, func Compare32(float32, float32) int #56491 diff --git a/src/math/all_test.go b/src/math/all_test.go index a37bf8a2be..886267bc17 100644 --- a/src/math/all_test.go +++ b/src/math/all_test.go @@ -2094,33 +2094,6 @@ var sqrt32 = []float32{ -5.0106036182710749e+00, } -type compareTest[F float32 | float64] struct { - x, y F - want int -} - -func compareCases[F float32 | float64]() []compareTest[F] { - zero, nan, inf := F(0.0), F(NaN()), F(Inf(0)) - return []compareTest[F]{ - {-nan, -inf, -1}, - {-inf, -nan, 1}, - {-inf, -Pi, -1}, - {-Pi, -inf, 1}, - {-Pi, -zero, -1}, - {-zero, -Pi, 1}, - {-zero, 0, -1}, - {0, -zero, 1}, - {0, Pi, -1}, - {Pi, 0, 1}, - {Pi, inf, -1}, - {inf, Pi, 1}, - {inf, nan, -1}, - {nan, inf, 1}, - {Pi, Pi, 0}, - {-nan, -nan, 0}, - } -} - func tolerance(a, b, e float64) bool { // Multiplying by e here can underflow denormal values to zero. // Check a==b so that at least if a and b are small and identical @@ -2288,22 +2261,6 @@ func TestCeil(t *testing.T) { } } -func TestCompare(t *testing.T) { - // -NaN < -∞ < -3.14 < -0 < 0 < 3.14 < ∞ < NaN - for _, c := range compareCases[float64]() { - cmp := Compare(c.x, c.y) - if cmp != c.want { - t.Errorf("Compare(%v, %v) = %d, want %v", c.x, c.y, cmp, c.want) - } - } - for _, c := range compareCases[float32]() { - cmp := Compare32(c.x, c.y) - if cmp != c.want { - t.Errorf("Compare32(%v, %v) = %d, want %v", c.x, c.y, cmp, c.want) - } - } -} - func TestCopysign(t *testing.T) { for i := 0; i < len(vf); i++ { if f := Copysign(vf[i], -1); copysign[i] != f { @@ -3363,22 +3320,6 @@ func BenchmarkCeil(b *testing.B) { GlobalF = x } -func BenchmarkCompare(b *testing.B) { - x := 0 - for i := 0; i < b.N; i++ { - x = Compare(1.5, 2.5) - } - GlobalI = x -} - -func BenchmarkCompare32(b *testing.B) { - x := 0 - for i := 0; i < b.N; i++ { - x = Compare32(1.5, 2.5) - } - GlobalI = x -} - var copysignNeg = -1.0 func BenchmarkCopysign(b *testing.B) { diff --git a/src/math/compare.go b/src/math/compare.go deleted file mode 100644 index 3798110072..0000000000 --- a/src/math/compare.go +++ /dev/null @@ -1,53 +0,0 @@ -// Copyright 2023 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 - -func sign[I int32 | int64](a, b I) int { - if a < b { - return -1 - } - if a > b { - return 1 - } - return 0 -} - -// Compare compares a and b such that -// -NaN is ordered before any other value, -// +NaN is ordered after any other value, -// and -0 is ordered before +0. -// In other words, it defines a total order over floats -// (according to the total-ordering predicate in IEEE-754, section 5.10). -// It returns 0 if a == b, -1 if a < b, and +1 if a > b. -func Compare(a, b float64) int { - // Perform a bitwise comparison (a < b) by casting the float64s into an int64s. - x := int64(Float64bits(a)) - y := int64(Float64bits(b)) - - // If a and b are both negative, flip the comparison so that we check a > b. - if x < 0 && y < 0 { - return sign(y, x) - } - return sign(x, y) -} - -// Compare32 compares a and b such that -// -NaN is ordered before any other value, -// +NaN is ordered after any other value, -// and -0 is ordered before +0. -// In other words, it defines a total order over floats -// (according to the total-ordering predicate in IEEE-754, section 5.10). -// It returns 0 if a == b, -1 if a < b, and +1 if a > b. -func Compare32(a, b float32) int { - // Perform a bitwise comparison (a < b) by casting the float32s into an int32s. - x := int32(Float32bits(a)) - y := int32(Float32bits(b)) - - // If a and b are both negative, flip the comparison so that we check a > b. - if x < 0 && y < 0 { - return sign(y, x) - } - return sign(x, y) -} -- 2.44.0