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// Copyright 2009 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 big
import (
"fmt"
"internal/testenv"
"math/bits"
"math/rand"
"strings"
"testing"
)
var isRaceBuilder = strings.HasSuffix(testenv.Builder(), "-race")
type funVV func(z, x, y []Word) (c Word)
type argVV struct {
z, x, y nat
c Word
}
var sumVV = []argVV{
{},
{nat{0}, nat{0}, nat{0}, 0},
{nat{1}, nat{1}, nat{0}, 0},
{nat{0}, nat{_M}, nat{1}, 1},
{nat{80235}, nat{12345}, nat{67890}, 0},
{nat{_M - 1}, nat{_M}, nat{_M}, 1},
{nat{0, 0, 0, 0}, nat{_M, _M, _M, _M}, nat{1, 0, 0, 0}, 1},
{nat{0, 0, 0, _M}, nat{_M, _M, _M, _M - 1}, nat{1, 0, 0, 0}, 0},
{nat{0, 0, 0, 0}, nat{_M, 0, _M, 0}, nat{1, _M, 0, _M}, 1},
}
func testFunVV(t *testing.T, msg string, f funVV, a argVV) {
z := make(nat, len(a.z))
c := f(z, a.x, a.y)
for i, zi := range z {
if zi != a.z[i] {
t.Errorf("%s%+v\n\tgot z[%d] = %#x; want %#x", msg, a, i, zi, a.z[i])
break
}
}
if c != a.c {
t.Errorf("%s%+v\n\tgot c = %#x; want %#x", msg, a, c, a.c)
}
}
func TestFunVV(t *testing.T) {
for _, a := range sumVV {
arg := a
testFunVV(t, "addVV_g", addVV_g, arg)
testFunVV(t, "addVV", addVV, arg)
arg = argVV{a.z, a.y, a.x, a.c}
testFunVV(t, "addVV_g symmetric", addVV_g, arg)
testFunVV(t, "addVV symmetric", addVV, arg)
arg = argVV{a.x, a.z, a.y, a.c}
testFunVV(t, "subVV_g", subVV_g, arg)
testFunVV(t, "subVV", subVV, arg)
arg = argVV{a.y, a.z, a.x, a.c}
testFunVV(t, "subVV_g symmetric", subVV_g, arg)
testFunVV(t, "subVV symmetric", subVV, arg)
}
}
// Always the same seed for reproducible results.
var rnd = rand.New(rand.NewSource(0))
func rndW() Word {
return Word(rnd.Int63()<<1 | rnd.Int63n(2))
}
func rndV(n int) []Word {
v := make([]Word, n)
for i := range v {
v[i] = rndW()
}
return v
}
var benchSizes = []int{1, 2, 3, 4, 5, 1e1, 1e2, 1e3, 1e4, 1e5}
func BenchmarkAddVV(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
x := rndV(n)
y := rndV(n)
z := make([]Word, n)
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _W))
for i := 0; i < b.N; i++ {
addVV(z, x, y)
}
})
}
}
func BenchmarkSubVV(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
x := rndV(n)
y := rndV(n)
z := make([]Word, n)
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _W))
for i := 0; i < b.N; i++ {
subVV(z, x, y)
}
})
}
}
type funVW func(z, x []Word, y Word) (c Word)
type argVW struct {
z, x nat
y Word
c Word
}
var sumVW = []argVW{
{},
{nil, nil, 2, 2},
{nat{0}, nat{0}, 0, 0},
{nat{1}, nat{0}, 1, 0},
{nat{1}, nat{1}, 0, 0},
{nat{0}, nat{_M}, 1, 1},
{nat{0, 0, 0, 0}, nat{_M, _M, _M, _M}, 1, 1},
{nat{585}, nat{314}, 271, 0},
}
var lshVW = []argVW{
{},
{nat{0}, nat{0}, 0, 0},
{nat{0}, nat{0}, 1, 0},
{nat{0}, nat{0}, 20, 0},
{nat{_M}, nat{_M}, 0, 0},
{nat{_M << 1 & _M}, nat{_M}, 1, 1},
{nat{_M << 20 & _M}, nat{_M}, 20, _M >> (_W - 20)},
{nat{_M, _M, _M}, nat{_M, _M, _M}, 0, 0},
{nat{_M << 1 & _M, _M, _M}, nat{_M, _M, _M}, 1, 1},
{nat{_M << 20 & _M, _M, _M}, nat{_M, _M, _M}, 20, _M >> (_W - 20)},
}
var rshVW = []argVW{
{},
{nat{0}, nat{0}, 0, 0},
{nat{0}, nat{0}, 1, 0},
{nat{0}, nat{0}, 20, 0},
{nat{_M}, nat{_M}, 0, 0},
{nat{_M >> 1}, nat{_M}, 1, _M << (_W - 1) & _M},
{nat{_M >> 20}, nat{_M}, 20, _M << (_W - 20) & _M},
{nat{_M, _M, _M}, nat{_M, _M, _M}, 0, 0},
{nat{_M, _M, _M >> 1}, nat{_M, _M, _M}, 1, _M << (_W - 1) & _M},
{nat{_M, _M, _M >> 20}, nat{_M, _M, _M}, 20, _M << (_W - 20) & _M},
}
func testFunVW(t *testing.T, msg string, f funVW, a argVW) {
z := make(nat, len(a.z))
c := f(z, a.x, a.y)
for i, zi := range z {
if zi != a.z[i] {
t.Errorf("%s%+v\n\tgot z[%d] = %#x; want %#x", msg, a, i, zi, a.z[i])
break
}
}
if c != a.c {
t.Errorf("%s%+v\n\tgot c = %#x; want %#x", msg, a, c, a.c)
}
}
func testFunVWext(t *testing.T, msg string, f funVW, f_g funVW, a argVW) {
// using the result of addVW_g/subVW_g as golden
z_g := make(nat, len(a.z))
c_g := f_g(z_g, a.x, a.y)
c := f(a.z, a.x, a.y)
for i, zi := range a.z {
if zi != z_g[i] {
t.Errorf("%s\n\tgot z[%d] = %#x; want %#x", msg, i, zi, z_g[i])
break
}
}
if c != c_g {
t.Errorf("%s\n\tgot c = %#x; want %#x", msg, c, c_g)
}
}
func makeFunVW(f func(z, x []Word, s uint) (c Word)) funVW {
return func(z, x []Word, s Word) (c Word) {
return f(z, x, uint(s))
}
}
func TestFunVW(t *testing.T) {
for _, a := range sumVW {
arg := a
testFunVW(t, "addVW_g", addVW_g, arg)
testFunVW(t, "addVW", addVW, arg)
arg = argVW{a.x, a.z, a.y, a.c}
testFunVW(t, "subVW_g", subVW_g, arg)
testFunVW(t, "subVW", subVW, arg)
}
shlVW_g := makeFunVW(shlVU_g)
shlVW := makeFunVW(shlVU)
for _, a := range lshVW {
arg := a
testFunVW(t, "shlVU_g", shlVW_g, arg)
testFunVW(t, "shlVU", shlVW, arg)
}
shrVW_g := makeFunVW(shrVU_g)
shrVW := makeFunVW(shrVU)
for _, a := range rshVW {
arg := a
testFunVW(t, "shrVU_g", shrVW_g, arg)
testFunVW(t, "shrVU", shrVW, arg)
}
}
// Construct a vector comprising the same word, usually '0' or 'maximum uint'
func makeWordVec(e Word, n int) []Word {
v := make([]Word, n)
for i := range v {
v[i] = e
}
return v
}
// Extended testing to addVW and subVW using various kinds of input data.
// We utilize the results of addVW_g and subVW_g as golden reference to check
// correctness.
func TestFunVWExt(t *testing.T) {
// 32 is the current threshold that triggers an optimized version of
// calculation for large-sized vector, ensure we have sizes around it tested.
var vwSizes = []int{0, 1, 3, 4, 5, 8, 9, 23, 31, 32, 33, 34, 35, 36, 50, 120}
for _, n := range vwSizes {
// vector of random numbers, using the result of addVW_g/subVW_g as golden
x := rndV(n)
y := rndW()
z := make(nat, n)
arg := argVW{z, x, y, 0}
testFunVWext(t, "addVW, random inputs", addVW, addVW_g, arg)
testFunVWext(t, "subVW, random inputs", subVW, subVW_g, arg)
// vector of random numbers, but make 'x' and 'z' share storage
arg = argVW{x, x, y, 0}
testFunVWext(t, "addVW, random inputs, sharing storage", addVW, addVW_g, arg)
testFunVWext(t, "subVW, random inputs, sharing storage", subVW, subVW_g, arg)
// vector of maximum uint, to force carry flag set in each 'add'
y = ^Word(0)
x = makeWordVec(y, n)
arg = argVW{z, x, y, 0}
testFunVWext(t, "addVW, vector of max uint", addVW, addVW_g, arg)
// vector of '0', to force carry flag set in each 'sub'
x = makeWordVec(0, n)
arg = argVW{z, x, 1, 0}
testFunVWext(t, "subVW, vector of zero", subVW, subVW_g, arg)
}
}
type argVU struct {
d []Word // d is a Word slice, the input parameters x and z come from this array.
l uint // l is the length of the input parameters x and z.
xp uint // xp is the starting position of the input parameter x, x := d[xp:xp+l].
zp uint // zp is the starting position of the input parameter z, z := d[zp:zp+l].
s uint // s is the shift number.
r []Word // r is the expected output result z.
c Word // c is the expected return value.
m string // message.
}
var argshlVUIn = []Word{1, 2, 4, 8, 16, 32, 64, 0, 0, 0}
var argshlVUr0 = []Word{1, 2, 4, 8, 16, 32, 64}
var argshlVUr1 = []Word{2, 4, 8, 16, 32, 64, 128}
var argshlVUrWm1 = []Word{1 << (_W - 1), 0, 1, 2, 4, 8, 16}
var argshlVU = []argVU{
// test cases for shlVU
{[]Word{1, _M, _M, _M, _M, _M, 3 << (_W - 2), 0}, 7, 0, 0, 1, []Word{2, _M - 1, _M, _M, _M, _M, 1<<(_W-1) + 1}, 1, "complete overlap of shlVU"},
{[]Word{1, _M, _M, _M, _M, _M, 3 << (_W - 2), 0, 0, 0, 0}, 7, 0, 3, 1, []Word{2, _M - 1, _M, _M, _M, _M, 1<<(_W-1) + 1}, 1, "partial overlap by half of shlVU"},
{[]Word{1, _M, _M, _M, _M, _M, 3 << (_W - 2), 0, 0, 0, 0, 0, 0, 0}, 7, 0, 6, 1, []Word{2, _M - 1, _M, _M, _M, _M, 1<<(_W-1) + 1}, 1, "partial overlap by 1 Word of shlVU"},
{[]Word{1, _M, _M, _M, _M, _M, 3 << (_W - 2), 0, 0, 0, 0, 0, 0, 0, 0}, 7, 0, 7, 1, []Word{2, _M - 1, _M, _M, _M, _M, 1<<(_W-1) + 1}, 1, "no overlap of shlVU"},
// additional test cases with shift values of 0, 1 and (_W-1)
{argshlVUIn, 7, 0, 0, 0, argshlVUr0, 0, "complete overlap of shlVU and shift of 0"},
{argshlVUIn, 7, 0, 0, 1, argshlVUr1, 0, "complete overlap of shlVU and shift of 1"},
{argshlVUIn, 7, 0, 0, _W - 1, argshlVUrWm1, 32, "complete overlap of shlVU and shift of _W - 1"},
{argshlVUIn, 7, 0, 1, 0, argshlVUr0, 0, "partial overlap by 6 Words of shlVU and shift of 0"},
{argshlVUIn, 7, 0, 1, 1, argshlVUr1, 0, "partial overlap by 6 Words of shlVU and shift of 1"},
{argshlVUIn, 7, 0, 1, _W - 1, argshlVUrWm1, 32, "partial overlap by 6 Words of shlVU and shift of _W - 1"},
{argshlVUIn, 7, 0, 2, 0, argshlVUr0, 0, "partial overlap by 5 Words of shlVU and shift of 0"},
{argshlVUIn, 7, 0, 2, 1, argshlVUr1, 0, "partial overlap by 5 Words of shlVU and shift of 1"},
{argshlVUIn, 7, 0, 2, _W - 1, argshlVUrWm1, 32, "partial overlap by 5 Words of shlVU abd shift of _W - 1"},
{argshlVUIn, 7, 0, 3, 0, argshlVUr0, 0, "partial overlap by 4 Words of shlVU and shift of 0"},
{argshlVUIn, 7, 0, 3, 1, argshlVUr1, 0, "partial overlap by 4 Words of shlVU and shift of 1"},
{argshlVUIn, 7, 0, 3, _W - 1, argshlVUrWm1, 32, "partial overlap by 4 Words of shlVU and shift of _W - 1"},
}
var argshrVUIn = []Word{0, 0, 0, 1, 2, 4, 8, 16, 32, 64}
var argshrVUr0 = []Word{1, 2, 4, 8, 16, 32, 64}
var argshrVUr1 = []Word{0, 1, 2, 4, 8, 16, 32}
var argshrVUrWm1 = []Word{4, 8, 16, 32, 64, 128, 0}
var argshrVU = []argVU{
// test cases for shrVU
{[]Word{0, 3, _M, _M, _M, _M, _M, 1 << (_W - 1)}, 7, 1, 1, 1, []Word{1<<(_W-1) + 1, _M, _M, _M, _M, _M >> 1, 1 << (_W - 2)}, 1 << (_W - 1), "complete overlap of shrVU"},
{[]Word{0, 0, 0, 0, 3, _M, _M, _M, _M, _M, 1 << (_W - 1)}, 7, 4, 1, 1, []Word{1<<(_W-1) + 1, _M, _M, _M, _M, _M >> 1, 1 << (_W - 2)}, 1 << (_W - 1), "partial overlap by half of shrVU"},
{[]Word{0, 0, 0, 0, 0, 0, 0, 3, _M, _M, _M, _M, _M, 1 << (_W - 1)}, 7, 7, 1, 1, []Word{1<<(_W-1) + 1, _M, _M, _M, _M, _M >> 1, 1 << (_W - 2)}, 1 << (_W - 1), "partial overlap by 1 Word of shrVU"},
{[]Word{0, 0, 0, 0, 0, 0, 0, 0, 3, _M, _M, _M, _M, _M, 1 << (_W - 1)}, 7, 8, 1, 1, []Word{1<<(_W-1) + 1, _M, _M, _M, _M, _M >> 1, 1 << (_W - 2)}, 1 << (_W - 1), "no overlap of shrVU"},
// additional test cases with shift values of 0, 1 and (_W-1)
{argshrVUIn, 7, 3, 3, 0, argshrVUr0, 0, "complete overlap of shrVU and shift of 0"},
{argshrVUIn, 7, 3, 3, 1, argshrVUr1, 1 << (_W - 1), "complete overlap of shrVU and shift of 1"},
{argshrVUIn, 7, 3, 3, _W - 1, argshrVUrWm1, 2, "complete overlap of shrVU and shift of _W - 1"},
{argshrVUIn, 7, 3, 2, 0, argshrVUr0, 0, "partial overlap by 6 Words of shrVU and shift of 0"},
{argshrVUIn, 7, 3, 2, 1, argshrVUr1, 1 << (_W - 1), "partial overlap by 6 Words of shrVU and shift of 1"},
{argshrVUIn, 7, 3, 2, _W - 1, argshrVUrWm1, 2, "partial overlap by 6 Words of shrVU and shift of _W - 1"},
{argshrVUIn, 7, 3, 1, 0, argshrVUr0, 0, "partial overlap by 5 Words of shrVU and shift of 0"},
{argshrVUIn, 7, 3, 1, 1, argshrVUr1, 1 << (_W - 1), "partial overlap by 5 Words of shrVU and shift of 1"},
{argshrVUIn, 7, 3, 1, _W - 1, argshrVUrWm1, 2, "partial overlap by 5 Words of shrVU and shift of _W - 1"},
{argshrVUIn, 7, 3, 0, 0, argshrVUr0, 0, "partial overlap by 4 Words of shrVU and shift of 0"},
{argshrVUIn, 7, 3, 0, 1, argshrVUr1, 1 << (_W - 1), "partial overlap by 4 Words of shrVU and shift of 1"},
{argshrVUIn, 7, 3, 0, _W - 1, argshrVUrWm1, 2, "partial overlap by 4 Words of shrVU and shift of _W - 1"},
}
func testShiftFunc(t *testing.T, f func(z, x []Word, s uint) Word, a argVU) {
// work on copy of a.d to preserve the original data.
b := make([]Word, len(a.d))
copy(b, a.d)
z := b[a.zp : a.zp+a.l]
x := b[a.xp : a.xp+a.l]
c := f(z, x, a.s)
for i, zi := range z {
if zi != a.r[i] {
t.Errorf("d := %v, %s(d[%d:%d], d[%d:%d], %d)\n\tgot z[%d] = %#x; want %#x", a.d, a.m, a.zp, a.zp+a.l, a.xp, a.xp+a.l, a.s, i, zi, a.r[i])
break
}
}
if c != a.c {
t.Errorf("d := %v, %s(d[%d:%d], d[%d:%d], %d)\n\tgot c = %#x; want %#x", a.d, a.m, a.zp, a.zp+a.l, a.xp, a.xp+a.l, a.s, c, a.c)
}
}
func TestShiftOverlap(t *testing.T) {
for _, a := range argshlVU {
arg := a
testShiftFunc(t, shlVU, arg)
}
for _, a := range argshrVU {
arg := a
testShiftFunc(t, shrVU, arg)
}
}
func TestIssue31084(t *testing.T) {
// compute 10^n via 5^n << n.
const n = 165
p := nat(nil).expNN(nat{5}, nat{n}, nil, false)
p = p.shl(p, n)
got := string(p.utoa(10))
want := "1" + strings.Repeat("0", n)
if got != want {
t.Errorf("shl(%v, %v)\n\tgot %s\n\twant %s", p, n, got, want)
}
}
const issue42838Value = "159309191113245227702888039776771180559110455519261878607388585338616290151305816094308987472018268594098344692611135542392730712890625"
func TestIssue42838(t *testing.T) {
const s = 192
z, _, _, _ := nat(nil).scan(strings.NewReader(issue42838Value), 0, false)
z = z.shl(z, s)
got := string(z.utoa(10))
want := "1" + strings.Repeat("0", s)
if got != want {
t.Errorf("shl(%v, %v)\n\tgot %s\n\twant %s", z, s, got, want)
}
}
func BenchmarkAddVW(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
x := rndV(n)
y := rndW()
z := make([]Word, n)
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _S))
for i := 0; i < b.N; i++ {
addVW(z, x, y)
}
})
}
}
// Benchmarking addVW using vector of maximum uint to force carry flag set
func BenchmarkAddVWext(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
y := ^Word(0)
x := makeWordVec(y, n)
z := make([]Word, n)
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _S))
for i := 0; i < b.N; i++ {
addVW(z, x, y)
}
})
}
}
func BenchmarkSubVW(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
x := rndV(n)
y := rndW()
z := make([]Word, n)
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _S))
for i := 0; i < b.N; i++ {
subVW(z, x, y)
}
})
}
}
// Benchmarking subVW using vector of zero to force carry flag set
func BenchmarkSubVWext(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
x := makeWordVec(0, n)
y := Word(1)
z := make([]Word, n)
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _S))
for i := 0; i < b.N; i++ {
subVW(z, x, y)
}
})
}
}
type funVWW func(z, x []Word, y, r Word) (c Word)
type argVWW struct {
z, x nat
y, r Word
c Word
}
var prodVWW = []argVWW{
{},
{nat{0}, nat{0}, 0, 0, 0},
{nat{991}, nat{0}, 0, 991, 0},
{nat{0}, nat{_M}, 0, 0, 0},
{nat{991}, nat{_M}, 0, 991, 0},
{nat{0}, nat{0}, _M, 0, 0},
{nat{991}, nat{0}, _M, 991, 0},
{nat{1}, nat{1}, 1, 0, 0},
{nat{992}, nat{1}, 1, 991, 0},
{nat{22793}, nat{991}, 23, 0, 0},
{nat{22800}, nat{991}, 23, 7, 0},
{nat{0, 0, 0, 22793}, nat{0, 0, 0, 991}, 23, 0, 0},
{nat{7, 0, 0, 22793}, nat{0, 0, 0, 991}, 23, 7, 0},
{nat{0, 0, 0, 0}, nat{7893475, 7395495, 798547395, 68943}, 0, 0, 0},
{nat{991, 0, 0, 0}, nat{7893475, 7395495, 798547395, 68943}, 0, 991, 0},
{nat{0, 0, 0, 0}, nat{0, 0, 0, 0}, 894375984, 0, 0},
{nat{991, 0, 0, 0}, nat{0, 0, 0, 0}, 894375984, 991, 0},
{nat{_M << 1 & _M}, nat{_M}, 1 << 1, 0, _M >> (_W - 1)},
{nat{_M<<1&_M + 1}, nat{_M}, 1 << 1, 1, _M >> (_W - 1)},
{nat{_M << 7 & _M}, nat{_M}, 1 << 7, 0, _M >> (_W - 7)},
{nat{_M<<7&_M + 1<<6}, nat{_M}, 1 << 7, 1 << 6, _M >> (_W - 7)},
{nat{_M << 7 & _M, _M, _M, _M}, nat{_M, _M, _M, _M}, 1 << 7, 0, _M >> (_W - 7)},
{nat{_M<<7&_M + 1<<6, _M, _M, _M}, nat{_M, _M, _M, _M}, 1 << 7, 1 << 6, _M >> (_W - 7)},
}
func testFunVWW(t *testing.T, msg string, f funVWW, a argVWW) {
z := make(nat, len(a.z))
c := f(z, a.x, a.y, a.r)
for i, zi := range z {
if zi != a.z[i] {
t.Errorf("%s%+v\n\tgot z[%d] = %#x; want %#x", msg, a, i, zi, a.z[i])
break
}
}
if c != a.c {
t.Errorf("%s%+v\n\tgot c = %#x; want %#x", msg, a, c, a.c)
}
}
// TODO(gri) mulAddVWW and divWVW are symmetric operations but
// their signature is not symmetric. Try to unify.
type funWVW func(z []Word, xn Word, x []Word, y Word) (r Word)
type argWVW struct {
z nat
xn Word
x nat
y Word
r Word
}
func testFunWVW(t *testing.T, msg string, f funWVW, a argWVW) {
z := make(nat, len(a.z))
r := f(z, a.xn, a.x, a.y)
for i, zi := range z {
if zi != a.z[i] {
t.Errorf("%s%+v\n\tgot z[%d] = %#x; want %#x", msg, a, i, zi, a.z[i])
break
}
}
if r != a.r {
t.Errorf("%s%+v\n\tgot r = %#x; want %#x", msg, a, r, a.r)
}
}
func TestFunVWW(t *testing.T) {
for _, a := range prodVWW {
arg := a
testFunVWW(t, "mulAddVWW_g", mulAddVWW_g, arg)
testFunVWW(t, "mulAddVWW", mulAddVWW, arg)
if a.y != 0 && a.r < a.y {
arg := argWVW{a.x, a.c, a.z, a.y, a.r}
testFunWVW(t, "divWVW", divWVW, arg)
}
}
}
var mulWWTests = []struct {
x, y Word
q, r Word
}{
{_M, _M, _M - 1, 1},
// 32 bit only: {0xc47dfa8c, 50911, 0x98a4, 0x998587f4},
}
func TestMulWW(t *testing.T) {
for i, test := range mulWWTests {
q, r := mulWW(test.x, test.y)
if q != test.q || r != test.r {
t.Errorf("#%d got (%x, %x) want (%x, %x)", i, q, r, test.q, test.r)
}
}
}
var mulAddWWWTests = []struct {
x, y, c Word
q, r Word
}{
// TODO(agl): These will only work on 64-bit platforms.
// {15064310297182388543, 0xe7df04d2d35d5d80, 13537600649892366549, 13644450054494335067, 10832252001440893781},
// {15064310297182388543, 0xdab2f18048baa68d, 13644450054494335067, 12869334219691522700, 14233854684711418382},
{_M, _M, 0, _M - 1, 1},
{_M, _M, _M, _M, 0},
}
func TestMulAddWWW(t *testing.T) {
for i, test := range mulAddWWWTests {
q, r := mulAddWWW_g(test.x, test.y, test.c)
if q != test.q || r != test.r {
t.Errorf("#%d got (%x, %x) want (%x, %x)", i, q, r, test.q, test.r)
}
}
}
var divWWTests = []struct {
x1, x0, y Word
q, r Word
}{
{_M >> 1, 0, _M, _M >> 1, _M >> 1},
{_M - (1 << (_W - 2)), _M, 3 << (_W - 2), _M, _M - (1 << (_W - 2))},
}
const testsNumber = 1 << 16
func TestDivWW(t *testing.T) {
i := 0
for i, test := range divWWTests {
rec := reciprocalWord(test.y)
q, r := divWW(test.x1, test.x0, test.y, rec)
if q != test.q || r != test.r {
t.Errorf("#%d got (%x, %x) want (%x, %x)", i, q, r, test.q, test.r)
}
}
//random tests
for ; i < testsNumber; i++ {
x1 := rndW()
x0 := rndW()
y := rndW()
if x1 >= y {
continue
}
rec := reciprocalWord(y)
qGot, rGot := divWW(x1, x0, y, rec)
qWant, rWant := bits.Div(uint(x1), uint(x0), uint(y))
if uint(qGot) != qWant || uint(rGot) != rWant {
t.Errorf("#%d got (%x, %x) want (%x, %x)", i, qGot, rGot, qWant, rWant)
}
}
}
func BenchmarkMulAddVWW(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
z := make([]Word, n+1)
x := rndV(n)
y := rndW()
r := rndW()
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _W))
for i := 0; i < b.N; i++ {
mulAddVWW(z, x, y, r)
}
})
}
}
func BenchmarkAddMulVVW(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
x := rndV(n)
y := rndW()
z := make([]Word, n)
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _W))
for i := 0; i < b.N; i++ {
addMulVVW(z, x, y)
}
})
}
}
func BenchmarkDivWVW(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
x := rndV(n)
y := rndW()
z := make([]Word, n)
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _W))
for i := 0; i < b.N; i++ {
divWVW(z, 0, x, y)
}
})
}
}
func BenchmarkNonZeroShifts(b *testing.B) {
for _, n := range benchSizes {
if isRaceBuilder && n > 1e3 {
continue
}
x := rndV(n)
s := uint(rand.Int63n(_W-2)) + 1 // avoid 0 and over-large shifts
z := make([]Word, n)
b.Run(fmt.Sprint(n), func(b *testing.B) {
b.SetBytes(int64(n * _W))
b.Run("shrVU", func(b *testing.B) {
for i := 0; i < b.N; i++ {
_ = shrVU(z, x, s)
}
})
b.Run("shlVU", func(b *testing.B) {
for i := 0; i < b.N; i++ {
_ = shlVU(z, x, s)
}
})
})
}
}