1// Copyright 2023 The Go Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style 3// license that can be found in the LICENSE file. 4 5package test 6 7import ( 8 "encoding/binary" 9 "testing" 10) 11 12var gv = [16]byte{0, 1, 2, 3, 4, 5, 6, 7, 8} 13 14//go:noinline 15func readGlobalUnaligned() uint64 { 16 return binary.LittleEndian.Uint64(gv[1:]) 17} 18 19func TestUnalignedGlobal(t *testing.T) { 20 // Note: this is a test not so much of the result of the read, but of 21 // the correct compilation of that read. On s390x unaligned global 22 // accesses fail to compile. 23 if got, want := readGlobalUnaligned(), uint64(0x0807060504030201); got != want { 24 t.Errorf("read global %x, want %x", got, want) 25 } 26} 27 28func TestSpillOfExtendedEndianLoads(t *testing.T) { 29 b := []byte{0xaa, 0xbb, 0xcc, 0xdd} 30 31 var testCases = []struct { 32 fn func([]byte) uint64 33 want uint64 34 }{ 35 {readUint16le, 0xbbaa}, 36 {readUint16be, 0xaabb}, 37 {readUint32le, 0xddccbbaa}, 38 {readUint32be, 0xaabbccdd}, 39 } 40 for _, test := range testCases { 41 if got := test.fn(b); got != test.want { 42 t.Errorf("got %x, want %x", got, test.want) 43 } 44 } 45} 46 47func readUint16le(b []byte) uint64 { 48 y := uint64(binary.LittleEndian.Uint16(b)) 49 nop() // force spill 50 return y 51} 52 53func readUint16be(b []byte) uint64 { 54 y := uint64(binary.BigEndian.Uint16(b)) 55 nop() // force spill 56 return y 57} 58 59func readUint32le(b []byte) uint64 { 60 y := uint64(binary.LittleEndian.Uint32(b)) 61 nop() // force spill 62 return y 63} 64 65func readUint32be(b []byte) uint64 { 66 y := uint64(binary.BigEndian.Uint32(b)) 67 nop() // force spill 68 return y 69} 70 71//go:noinline 72func nop() { 73} 74 75type T32 struct { 76 a, b uint32 77} 78 79//go:noinline 80func (t *T32) bigEndianLoad() uint64 { 81 return uint64(t.a)<<32 | uint64(t.b) 82} 83 84//go:noinline 85func (t *T32) littleEndianLoad() uint64 { 86 return uint64(t.a) | (uint64(t.b) << 32) 87} 88 89//go:noinline 90func (t *T32) bigEndianStore(x uint64) { 91 t.a = uint32(x >> 32) 92 t.b = uint32(x) 93} 94 95//go:noinline 96func (t *T32) littleEndianStore(x uint64) { 97 t.a = uint32(x) 98 t.b = uint32(x >> 32) 99} 100 101type T16 struct { 102 a, b uint16 103} 104 105//go:noinline 106func (t *T16) bigEndianLoad() uint32 { 107 return uint32(t.a)<<16 | uint32(t.b) 108} 109 110//go:noinline 111func (t *T16) littleEndianLoad() uint32 { 112 return uint32(t.a) | (uint32(t.b) << 16) 113} 114 115//go:noinline 116func (t *T16) bigEndianStore(x uint32) { 117 t.a = uint16(x >> 16) 118 t.b = uint16(x) 119} 120 121//go:noinline 122func (t *T16) littleEndianStore(x uint32) { 123 t.a = uint16(x) 124 t.b = uint16(x >> 16) 125} 126 127type T8 struct { 128 a, b uint8 129} 130 131//go:noinline 132func (t *T8) bigEndianLoad() uint16 { 133 return uint16(t.a)<<8 | uint16(t.b) 134} 135 136//go:noinline 137func (t *T8) littleEndianLoad() uint16 { 138 return uint16(t.a) | (uint16(t.b) << 8) 139} 140 141//go:noinline 142func (t *T8) bigEndianStore(x uint16) { 143 t.a = uint8(x >> 8) 144 t.b = uint8(x) 145} 146 147//go:noinline 148func (t *T8) littleEndianStore(x uint16) { 149 t.a = uint8(x) 150 t.b = uint8(x >> 8) 151} 152 153func TestIssue64468(t *testing.T) { 154 t32 := T32{1, 2} 155 if got, want := t32.bigEndianLoad(), uint64(1<<32+2); got != want { 156 t.Errorf("T32.bigEndianLoad got %x want %x\n", got, want) 157 } 158 if got, want := t32.littleEndianLoad(), uint64(1+2<<32); got != want { 159 t.Errorf("T32.littleEndianLoad got %x want %x\n", got, want) 160 } 161 t16 := T16{1, 2} 162 if got, want := t16.bigEndianLoad(), uint32(1<<16+2); got != want { 163 t.Errorf("T16.bigEndianLoad got %x want %x\n", got, want) 164 } 165 if got, want := t16.littleEndianLoad(), uint32(1+2<<16); got != want { 166 t.Errorf("T16.littleEndianLoad got %x want %x\n", got, want) 167 } 168 t8 := T8{1, 2} 169 if got, want := t8.bigEndianLoad(), uint16(1<<8+2); got != want { 170 t.Errorf("T8.bigEndianLoad got %x want %x\n", got, want) 171 } 172 if got, want := t8.littleEndianLoad(), uint16(1+2<<8); got != want { 173 t.Errorf("T8.littleEndianLoad got %x want %x\n", got, want) 174 } 175 t32.bigEndianStore(1<<32 + 2) 176 if got, want := t32, (T32{1, 2}); got != want { 177 t.Errorf("T32.bigEndianStore got %x want %x\n", got, want) 178 } 179 t32.littleEndianStore(1<<32 + 2) 180 if got, want := t32, (T32{2, 1}); got != want { 181 t.Errorf("T32.littleEndianStore got %x want %x\n", got, want) 182 } 183 t16.bigEndianStore(1<<16 + 2) 184 if got, want := t16, (T16{1, 2}); got != want { 185 t.Errorf("T16.bigEndianStore got %x want %x\n", got, want) 186 } 187 t16.littleEndianStore(1<<16 + 2) 188 if got, want := t16, (T16{2, 1}); got != want { 189 t.Errorf("T16.littleEndianStore got %x want %x\n", got, want) 190 } 191 t8.bigEndianStore(1<<8 + 2) 192 if got, want := t8, (T8{1, 2}); got != want { 193 t.Errorf("T8.bigEndianStore got %x want %x\n", got, want) 194 } 195 t8.littleEndianStore(1<<8 + 2) 196 if got, want := t8, (T8{2, 1}); got != want { 197 t.Errorf("T8.littleEndianStore got %x want %x\n", got, want) 198 } 199} 200