github.com/q45/go@v0.0.0-20151101211701-a4fb8c13db3f/src/go/types/testdata/shifts.src (about) 1 // Copyright 2013 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 5 package shifts 6 7 func shifts0() { 8 // basic constant shifts 9 const ( 10 s = 10 11 _ = 0<<0 12 _ = 1<<s 13 _ = 1<<- /* ERROR "stupid shift" */ 1 14 _ = 1<<1075 /* ERROR "stupid shift" */ 15 _ = 2.0<<1 16 17 _ int = 2<<s 18 _ float32 = 2<<s 19 _ complex64 = 2<<s 20 21 _ int = 2.0<<s 22 _ float32 = 2.0<<s 23 _ complex64 = 2.0<<s 24 25 _ int = 'a'<<s 26 _ float32 = 'a'<<s 27 _ complex64 = 'a'<<s 28 ) 29 } 30 31 func shifts1() { 32 // basic non-constant shifts 33 var ( 34 i int 35 u uint 36 37 _ = 1<<0 38 _ = 1<<i /* ERROR "must be unsigned" */ 39 _ = 1<<u 40 _ = 1<<"foo" /* ERROR "cannot convert" */ 41 _ = i<<0 42 _ = i<<- /* ERROR "must not be negative" */ 1 43 _ = 1 /* ERROR "overflows" */ <<100 44 45 _ uint = 1 << 0 46 _ uint = 1 << u 47 _ float32 = 1 /* ERROR "must be integer" */ << u 48 ) 49 } 50 51 func shifts2() { 52 // from the spec 53 var ( 54 s uint = 33 55 i = 1<<s // 1 has type int 56 j int32 = 1<<s // 1 has type int32; j == 0 57 k = uint64(1<<s) // 1 has type uint64; k == 1<<33 58 m int = 1.0<<s // 1.0 has type int 59 n = 1.0<<s != i // 1.0 has type int; n == false if ints are 32bits in size 60 o = 1<<s == 2<<s // 1 and 2 have type int; o == true if ints are 32bits in size 61 p = 1<<s == 1<<33 // illegal if ints are 32bits in size: 1 has type int, but 1<<33 overflows int 62 u = 1.0 /* ERROR "must be integer" */ <<s // illegal: 1.0 has type float64, cannot shift 63 u1 = 1.0 /* ERROR "must be integer" */ <<s != 0 // illegal: 1.0 has type float64, cannot shift 64 u2 = 1 /* ERROR "must be integer" */ <<s != 1.0 // illegal: 1 has type float64, cannot shift 65 v float32 = 1 /* ERROR "must be integer" */ <<s // illegal: 1 has type float32, cannot shift 66 w int64 = 1.0<<33 // 1.0<<33 is a constant shift expression 67 ) 68 _, _, _, _, _, _, _, _, _, _, _, _ = i, j, k, m, n, o, p, u, u1, u2, v, w 69 } 70 71 func shifts3(a int16, b float32) { 72 // random tests 73 var ( 74 s uint = 11 75 u = 1 /* ERROR "must be integer" */ <<s + 1.0 76 v complex128 = 1 /* ERROR "must be integer" */ << s + 1.0 /* ERROR "must be integer" */ << s + 1 77 ) 78 x := 1.0 /* ERROR "must be integer" */ <<s + 1 79 shifts3(1.0 << s, 1 /* ERROR "must be integer" */ >> s) 80 _, _, _ = u, v, x 81 } 82 83 func shifts4() { 84 // shifts in comparisons w/ untyped operands 85 var s uint 86 87 _ = 1<<s == 1 88 _ = 1 /* ERROR "integer" */ <<s == 1. 89 _ = 1. /* ERROR "integer" */ <<s == 1 90 _ = 1. /* ERROR "integer" */ <<s == 1. 91 92 _ = 1<<s + 1 == 1 93 _ = 1 /* ERROR "integer" */ <<s + 1 == 1. 94 _ = 1 /* ERROR "integer" */ <<s + 1. == 1 95 _ = 1 /* ERROR "integer" */ <<s + 1. == 1. 96 _ = 1. /* ERROR "integer" */ <<s + 1 == 1 97 _ = 1. /* ERROR "integer" */ <<s + 1 == 1. 98 _ = 1. /* ERROR "integer" */ <<s + 1. == 1 99 _ = 1. /* ERROR "integer" */ <<s + 1. == 1. 100 101 _ = 1<<s == 1<<s 102 _ = 1 /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s 103 _ = 1. /* ERROR "integer" */ <<s == 1 /* ERROR "integer" */ <<s 104 _ = 1. /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s 105 106 _ = 1<<s + 1<<s == 1 107 _ = 1 /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1. 108 _ = 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1 109 _ = 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1. 110 _ = 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1 111 _ = 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1. 112 _ = 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1 113 _ = 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1. 114 115 _ = 1<<s + 1<<s == 1<<s + 1<<s 116 _ = 1 /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s 117 _ = 1 /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s 118 _ = 1 /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s 119 _ = 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1 /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s 120 _ = 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s 121 _ = 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s 122 _ = 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s 123 _ = 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1 /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s 124 _ = 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s 125 _ = 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s 126 _ = 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s 127 _ = 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1 /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s 128 _ = 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1 /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s 129 _ = 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s + 1 /* ERROR "integer" */ <<s 130 _ = 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s == 1. /* ERROR "integer" */ <<s + 1. /* ERROR "integer" */ <<s 131 } 132 133 func shifts5() { 134 // shifts in comparisons w/ typed operands 135 var s uint 136 var x int 137 138 _ = 1<<s == x 139 _ = 1.<<s == x 140 _ = 1.1 /* ERROR "int" */ <<s == x 141 142 _ = 1<<s + x == 1 143 _ = 1<<s + x == 1. 144 _ = 1<<s + x == 1.1 /* ERROR "int" */ 145 _ = 1.<<s + x == 1 146 _ = 1.<<s + x == 1. 147 _ = 1.<<s + x == 1.1 /* ERROR "int" */ 148 _ = 1.1 /* ERROR "int" */ <<s + x == 1 149 _ = 1.1 /* ERROR "int" */ <<s + x == 1. 150 _ = 1.1 /* ERROR "int" */ <<s + x == 1.1 151 152 _ = 1<<s == x<<s 153 _ = 1.<<s == x<<s 154 _ = 1.1 /* ERROR "int" */ <<s == x<<s 155 } 156 157 func shifts6() { 158 // shifts as operands in non-arithmetic operations and as arguments 159 var a [10]int 160 var s uint 161 162 _ = a[1<<s] 163 _ = a[1.0] 164 _ = a[1.0<<s] 165 166 _ = make([]int, 1.0) 167 _ = make([]int, 1.0<<s) 168 _ = make([]int, 1.1 /* ERROR "must be integer" */ <<s) 169 170 _ = float32(1) 171 _ = float32(1 /* ERROR "must be integer" */ <<s) 172 _ = float32(1.0) 173 _ = float32(1.0 /* ERROR "must be integer" */ <<s) 174 _ = float32(1.1 /* ERROR "must be integer" */ <<s) 175 176 var b []int 177 _ = append(b, 1<<s) 178 _ = append(b, 1.0<<s) 179 _ = append(b, 1.1 /* ERROR "must be integer" */ <<s) 180 181 _ = append(b, 1<<s) 182 _ = append(b, 1.0<<s) // should fail - see TODO in append code 183 _ = append(b, 1.1 /* ERROR "must be integer" */ <<s) 184 185 _ = complex(1.0 /* ERROR "must be integer" */ <<s, 0) 186 _ = complex(1.1 /* ERROR "must be integer" */ <<s, 0) 187 _ = complex(0, 1.0 /* ERROR "must be integer" */ <<s) 188 _ = complex(0, 1.1 /* ERROR "must be integer" */ <<s) 189 190 // TODO(gri) The delete below is not type-checked correctly yet. 191 // var m1 map[int]string 192 // delete(m1, 1<<s) 193 } 194 195 func shifts7() { 196 // shifts of shifts 197 var s uint 198 var x int 199 _ = x 200 201 _ = 1<<(1<<s) 202 _ = 1<<(1.<<s) 203 _ = 1. /* ERROR "integer" */ <<(1<<s) 204 _ = 1. /* ERROR "integer" */ <<(1.<<s) 205 206 x = 1<<(1<<s) 207 x = 1<<(1.<<s) 208 x = 1.<<(1<<s) 209 x = 1.<<(1.<<s) 210 211 _ = (1<<s)<<(1<<s) 212 _ = (1<<s)<<(1.<<s) 213 _ = ( /* ERROR "integer" */ 1.<<s)<<(1<<s) 214 _ = ( /* ERROR "integer" */ 1.<<s)<<(1.<<s) 215 216 x = (1<<s)<<(1<<s) 217 x = (1<<s)<<(1.<<s) 218 x = ( /* ERROR "integer" */ 1.<<s)<<(1<<s) 219 x = ( /* ERROR "integer" */ 1.<<s)<<(1.<<s) 220 } 221 222 func shifts8() { 223 // shift examples from shift discussion: better error messages 224 var s uint 225 _ = 1.0 /* ERROR "shifted operand 1.0 \(type float64\) must be integer" */ <<s == 1 226 _ = 1.0 /* ERROR "shifted operand 1.0 \(type float64\) must be integer" */ <<s == 1.0 227 _ = 1 /* ERROR "shifted operand 1 \(type float64\) must be integer" */ <<s == 1.0 228 _ = 1 /* ERROR "shifted operand 1 \(type float64\) must be integer" */ <<s + 1.0 == 1 229 _ = 1 /* ERROR "shifted operand 1 \(type float64\) must be integer" */ <<s + 1.1 == 1 230 _ = 1 /* ERROR "shifted operand 1 \(type float64\) must be integer" */ <<s + 1 == 1.0 231 232 // additional cases 233 _ = complex(1.0 /* ERROR "shifted operand 1.0 \(type float64\) must be integer" */ <<s, 1) 234 _ = complex(1.0, 1 /* ERROR "shifted operand 1 \(type float64\) must be integer" */ <<s) 235 236 _ = int(1.<<s) 237 _ = int(1.1 /* ERROR "shifted operand .* must be integer" */ <<s) 238 _ = float32(1 /* ERROR "shifted operand .* must be integer" */ <<s) 239 _ = float32(1. /* ERROR "shifted operand .* must be integer" */ <<s) 240 _ = float32(1.1 /* ERROR "shifted operand .* must be integer" */ <<s) 241 // TODO(gri) the error messages for these two are incorrect - disabled for now 242 // _ = complex64(1<<s) 243 // _ = complex64(1.<<s) 244 _ = complex64(1.1 /* ERROR "shifted operand .* must be integer" */ <<s) 245 } 246 247 func shifts9() { 248 // various originally failing snippets of code from the std library 249 // from src/compress/lzw/reader.go:90 250 { 251 var d struct { 252 bits uint32 253 width uint 254 } 255 _ = uint16(d.bits & (1<<d.width - 1)) 256 } 257 258 // from src/debug/dwarf/buf.go:116 259 { 260 var ux uint64 261 var bits uint 262 x := int64(ux) 263 if x&(1<<(bits-1)) != 0 {} 264 } 265 266 // from src/encoding/asn1/asn1.go:160 267 { 268 var bytes []byte 269 if bytes[len(bytes)-1]&((1<<bytes[0])-1) != 0 {} 270 } 271 272 // from src/math/big/rat.go:140 273 { 274 var exp int 275 var mantissa uint64 276 shift := uint64(-1022 - (exp - 1)) // [1..53) 277 _ = mantissa & (1<<shift - 1) 278 } 279 280 // from src/net/interface.go:51 281 { 282 type Flags uint 283 var f Flags 284 var i int 285 if f&(1<<uint(i)) != 0 {} 286 } 287 288 // from src/runtime/softfloat64.go:234 289 { 290 var gm uint64 291 var shift uint 292 _ = gm & (1<<shift - 1) 293 } 294 295 // from src/strconv/atof.go:326 296 { 297 var mant uint64 298 var mantbits uint 299 if mant == 2<<mantbits {} 300 } 301 302 // from src/route_bsd.go:82 303 { 304 var Addrs int32 305 const rtaRtMask = 1 306 var i uint 307 if Addrs&rtaRtMask&(1<<i) == 0 {} 308 } 309 310 // from src/text/scanner/scanner.go:540 311 { 312 var s struct { Whitespace uint64 } 313 var ch rune 314 for s.Whitespace&(1<<uint(ch)) != 0 {} 315 } 316 } 317 318 func issue5895() { 319 var x = 'a' << 1 // type of x must be rune 320 var _ rune = x 321 } 322 323 func issue11325() { 324 var _ = 0 >> 1.1 /* ERROR "must be unsigned integer" */ // example from issue 11325 325 _ = 0 >> 1.1 /* ERROR "must be unsigned integer" */ 326 _ = 0 << 1.1 /* ERROR "must be unsigned integer" */ 327 _ = 0 >> 1. 328 _ = 1 >> 1.1 /* ERROR "must be unsigned integer" */ 329 _ = 1 >> 1. 330 _ = 1. >> 1 331 _ = 1. >> 1. 332 _ = 1.1 /* ERROR "must be integer" */ >> 1 333 } 334 335 func issue11594() { 336 var _ = complex64 /* ERROR "must be integer" */ (1) << 2 // example from issue 11594 337 _ = float32 /* ERROR "must be integer" */ (0) << 1 338 _ = float64 /* ERROR "must be integer" */ (0) >> 2 339 _ = complex64 /* ERROR "must be integer" */ (0) << 3 340 _ = complex64 /* ERROR "must be integer" */ (0) >> 4 341 }