github.com/mh-cbon/go@v0.0.0-20160603070303-9e112a3fe4c0/src/cmd/compile/internal/ssa/gen/genericOps.go (about) 1 // Copyright 2015 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 // +build ignore 6 7 package main 8 9 // Generic opcodes typically specify a width. The inputs and outputs 10 // of that op are the given number of bits wide. There is no notion of 11 // "sign", so Add32 can be used both for signed and unsigned 32-bit 12 // addition. 13 14 // Signed/unsigned is explicit with the extension ops 15 // (SignExt*/ZeroExt*) and implicit as the arg to some opcodes 16 // (e.g. the second argument to shifts is unsigned). If not mentioned, 17 // all args take signed inputs, or don't care whether their inputs 18 // are signed or unsigned. 19 20 // Unused portions of AuxInt are filled by sign-extending the used portion. 21 // Users of AuxInt which interpret AuxInt as unsigned (e.g. shifts) must be careful. 22 var genericOps = []opData{ 23 // 2-input arithmetic 24 // Types must be consistent with Go typing. Add, for example, must take two values 25 // of the same type and produces that same type. 26 {name: "Add8", argLength: 2, commutative: true}, // arg0 + arg1 27 {name: "Add16", argLength: 2, commutative: true}, 28 {name: "Add32", argLength: 2, commutative: true}, 29 {name: "Add64", argLength: 2, commutative: true}, 30 {name: "AddPtr", argLength: 2}, // For address calculations. arg0 is a pointer and arg1 is an int. 31 {name: "Add32F", argLength: 2}, 32 {name: "Add64F", argLength: 2}, 33 34 {name: "Sub8", argLength: 2}, // arg0 - arg1 35 {name: "Sub16", argLength: 2}, 36 {name: "Sub32", argLength: 2}, 37 {name: "Sub64", argLength: 2}, 38 {name: "SubPtr", argLength: 2}, 39 {name: "Sub32F", argLength: 2}, 40 {name: "Sub64F", argLength: 2}, 41 42 {name: "Mul8", argLength: 2, commutative: true}, // arg0 * arg1 43 {name: "Mul16", argLength: 2, commutative: true}, 44 {name: "Mul32", argLength: 2, commutative: true}, 45 {name: "Mul64", argLength: 2, commutative: true}, 46 {name: "Mul32F", argLength: 2}, 47 {name: "Mul64F", argLength: 2}, 48 49 {name: "Div32F", argLength: 2}, // arg0 / arg1 50 {name: "Div64F", argLength: 2}, 51 52 {name: "Hmul8", argLength: 2}, // (arg0 * arg1) >> width, signed 53 {name: "Hmul8u", argLength: 2}, // (arg0 * arg1) >> width, unsigned 54 {name: "Hmul16", argLength: 2}, 55 {name: "Hmul16u", argLength: 2}, 56 {name: "Hmul32", argLength: 2}, 57 {name: "Hmul32u", argLength: 2}, 58 {name: "Hmul64", argLength: 2}, 59 {name: "Hmul64u", argLength: 2}, 60 61 // Weird special instruction for strength reduction of divides. 62 {name: "Avg64u", argLength: 2}, // (uint64(arg0) + uint64(arg1)) / 2, correct to all 64 bits. 63 64 {name: "Div8", argLength: 2}, // arg0 / arg1, signed 65 {name: "Div8u", argLength: 2}, // arg0 / arg1, unsigned 66 {name: "Div16", argLength: 2}, 67 {name: "Div16u", argLength: 2}, 68 {name: "Div32", argLength: 2}, 69 {name: "Div32u", argLength: 2}, 70 {name: "Div64", argLength: 2}, 71 {name: "Div64u", argLength: 2}, 72 73 {name: "Mod8", argLength: 2}, // arg0 % arg1, signed 74 {name: "Mod8u", argLength: 2}, // arg0 % arg1, unsigned 75 {name: "Mod16", argLength: 2}, 76 {name: "Mod16u", argLength: 2}, 77 {name: "Mod32", argLength: 2}, 78 {name: "Mod32u", argLength: 2}, 79 {name: "Mod64", argLength: 2}, 80 {name: "Mod64u", argLength: 2}, 81 82 {name: "And8", argLength: 2, commutative: true}, // arg0 & arg1 83 {name: "And16", argLength: 2, commutative: true}, 84 {name: "And32", argLength: 2, commutative: true}, 85 {name: "And64", argLength: 2, commutative: true}, 86 87 {name: "Or8", argLength: 2, commutative: true}, // arg0 | arg1 88 {name: "Or16", argLength: 2, commutative: true}, 89 {name: "Or32", argLength: 2, commutative: true}, 90 {name: "Or64", argLength: 2, commutative: true}, 91 92 {name: "Xor8", argLength: 2, commutative: true}, // arg0 ^ arg1 93 {name: "Xor16", argLength: 2, commutative: true}, 94 {name: "Xor32", argLength: 2, commutative: true}, 95 {name: "Xor64", argLength: 2, commutative: true}, 96 97 // For shifts, AxB means the shifted value has A bits and the shift amount has B bits. 98 // Shift amounts are considered unsigned. 99 {name: "Lsh8x8", argLength: 2}, // arg0 << arg1 100 {name: "Lsh8x16", argLength: 2}, 101 {name: "Lsh8x32", argLength: 2}, 102 {name: "Lsh8x64", argLength: 2}, 103 {name: "Lsh16x8", argLength: 2}, 104 {name: "Lsh16x16", argLength: 2}, 105 {name: "Lsh16x32", argLength: 2}, 106 {name: "Lsh16x64", argLength: 2}, 107 {name: "Lsh32x8", argLength: 2}, 108 {name: "Lsh32x16", argLength: 2}, 109 {name: "Lsh32x32", argLength: 2}, 110 {name: "Lsh32x64", argLength: 2}, 111 {name: "Lsh64x8", argLength: 2}, 112 {name: "Lsh64x16", argLength: 2}, 113 {name: "Lsh64x32", argLength: 2}, 114 {name: "Lsh64x64", argLength: 2}, 115 116 {name: "Rsh8x8", argLength: 2}, // arg0 >> arg1, signed 117 {name: "Rsh8x16", argLength: 2}, 118 {name: "Rsh8x32", argLength: 2}, 119 {name: "Rsh8x64", argLength: 2}, 120 {name: "Rsh16x8", argLength: 2}, 121 {name: "Rsh16x16", argLength: 2}, 122 {name: "Rsh16x32", argLength: 2}, 123 {name: "Rsh16x64", argLength: 2}, 124 {name: "Rsh32x8", argLength: 2}, 125 {name: "Rsh32x16", argLength: 2}, 126 {name: "Rsh32x32", argLength: 2}, 127 {name: "Rsh32x64", argLength: 2}, 128 {name: "Rsh64x8", argLength: 2}, 129 {name: "Rsh64x16", argLength: 2}, 130 {name: "Rsh64x32", argLength: 2}, 131 {name: "Rsh64x64", argLength: 2}, 132 133 {name: "Rsh8Ux8", argLength: 2}, // arg0 >> arg1, unsigned 134 {name: "Rsh8Ux16", argLength: 2}, 135 {name: "Rsh8Ux32", argLength: 2}, 136 {name: "Rsh8Ux64", argLength: 2}, 137 {name: "Rsh16Ux8", argLength: 2}, 138 {name: "Rsh16Ux16", argLength: 2}, 139 {name: "Rsh16Ux32", argLength: 2}, 140 {name: "Rsh16Ux64", argLength: 2}, 141 {name: "Rsh32Ux8", argLength: 2}, 142 {name: "Rsh32Ux16", argLength: 2}, 143 {name: "Rsh32Ux32", argLength: 2}, 144 {name: "Rsh32Ux64", argLength: 2}, 145 {name: "Rsh64Ux8", argLength: 2}, 146 {name: "Rsh64Ux16", argLength: 2}, 147 {name: "Rsh64Ux32", argLength: 2}, 148 {name: "Rsh64Ux64", argLength: 2}, 149 150 // (Left) rotates replace pattern matches in the front end 151 // of (arg0 << arg1) ^ (arg0 >> (A-arg1)) 152 // where A is the bit width of arg0 and result. 153 // Note that because rotates are pattern-matched from 154 // shifts, that a rotate of arg1=A+k (k > 0) bits originated from 155 // (arg0 << A+k) ^ (arg0 >> -k) = 156 // 0 ^ arg0>>huge_unsigned = 157 // 0 ^ 0 = 0 158 // which is not the same as a rotation by A+k 159 // 160 // However, in the specific case of k = 0, the result of 161 // the shift idiom is the same as the result for the 162 // rotate idiom, i.e., result=arg0. 163 // This is different from shifts, where 164 // arg0 << A is defined to be zero. 165 // 166 // Because of this, and also because the primary use case 167 // for rotates is hashing and crypto code with constant 168 // distance, rotate instructions are only substituted 169 // when arg1 is a constant between 1 and A-1, inclusive. 170 {name: "Lrot8", argLength: 1, aux: "Int64"}, 171 {name: "Lrot16", argLength: 1, aux: "Int64"}, 172 {name: "Lrot32", argLength: 1, aux: "Int64"}, 173 {name: "Lrot64", argLength: 1, aux: "Int64"}, 174 175 // 2-input comparisons 176 {name: "Eq8", argLength: 2, commutative: true}, // arg0 == arg1 177 {name: "Eq16", argLength: 2, commutative: true}, 178 {name: "Eq32", argLength: 2, commutative: true}, 179 {name: "Eq64", argLength: 2, commutative: true}, 180 {name: "EqPtr", argLength: 2, commutative: true}, 181 {name: "EqInter", argLength: 2}, // arg0 or arg1 is nil; other cases handled by frontend 182 {name: "EqSlice", argLength: 2}, // arg0 or arg1 is nil; other cases handled by frontend 183 {name: "Eq32F", argLength: 2}, 184 {name: "Eq64F", argLength: 2}, 185 186 {name: "Neq8", argLength: 2, commutative: true}, // arg0 != arg1 187 {name: "Neq16", argLength: 2, commutative: true}, 188 {name: "Neq32", argLength: 2, commutative: true}, 189 {name: "Neq64", argLength: 2, commutative: true}, 190 {name: "NeqPtr", argLength: 2, commutative: true}, 191 {name: "NeqInter", argLength: 2}, // arg0 or arg1 is nil; other cases handled by frontend 192 {name: "NeqSlice", argLength: 2}, // arg0 or arg1 is nil; other cases handled by frontend 193 {name: "Neq32F", argLength: 2}, 194 {name: "Neq64F", argLength: 2}, 195 196 {name: "Less8", argLength: 2}, // arg0 < arg1, signed 197 {name: "Less8U", argLength: 2}, // arg0 < arg1, unsigned 198 {name: "Less16", argLength: 2}, 199 {name: "Less16U", argLength: 2}, 200 {name: "Less32", argLength: 2}, 201 {name: "Less32U", argLength: 2}, 202 {name: "Less64", argLength: 2}, 203 {name: "Less64U", argLength: 2}, 204 {name: "Less32F", argLength: 2}, 205 {name: "Less64F", argLength: 2}, 206 207 {name: "Leq8", argLength: 2}, // arg0 <= arg1, signed 208 {name: "Leq8U", argLength: 2}, // arg0 <= arg1, unsigned 209 {name: "Leq16", argLength: 2}, 210 {name: "Leq16U", argLength: 2}, 211 {name: "Leq32", argLength: 2}, 212 {name: "Leq32U", argLength: 2}, 213 {name: "Leq64", argLength: 2}, 214 {name: "Leq64U", argLength: 2}, 215 {name: "Leq32F", argLength: 2}, 216 {name: "Leq64F", argLength: 2}, 217 218 {name: "Greater8", argLength: 2}, // arg0 > arg1, signed 219 {name: "Greater8U", argLength: 2}, // arg0 > arg1, unsigned 220 {name: "Greater16", argLength: 2}, 221 {name: "Greater16U", argLength: 2}, 222 {name: "Greater32", argLength: 2}, 223 {name: "Greater32U", argLength: 2}, 224 {name: "Greater64", argLength: 2}, 225 {name: "Greater64U", argLength: 2}, 226 {name: "Greater32F", argLength: 2}, 227 {name: "Greater64F", argLength: 2}, 228 229 {name: "Geq8", argLength: 2}, // arg0 <= arg1, signed 230 {name: "Geq8U", argLength: 2}, // arg0 <= arg1, unsigned 231 {name: "Geq16", argLength: 2}, 232 {name: "Geq16U", argLength: 2}, 233 {name: "Geq32", argLength: 2}, 234 {name: "Geq32U", argLength: 2}, 235 {name: "Geq64", argLength: 2}, 236 {name: "Geq64U", argLength: 2}, 237 {name: "Geq32F", argLength: 2}, 238 {name: "Geq64F", argLength: 2}, 239 240 // boolean ops 241 {name: "AndB", argLength: 2}, // arg0 && arg1 (not shortcircuited) 242 {name: "OrB", argLength: 2}, // arg0 || arg1 (not shortcircuited) 243 {name: "EqB", argLength: 2}, // arg0 == arg1 244 {name: "NeqB", argLength: 2}, // arg0 != arg1 245 {name: "Not", argLength: 1}, // !arg0, boolean 246 247 // 1-input ops 248 {name: "Neg8", argLength: 1}, // -arg0 249 {name: "Neg16", argLength: 1}, 250 {name: "Neg32", argLength: 1}, 251 {name: "Neg64", argLength: 1}, 252 {name: "Neg32F", argLength: 1}, 253 {name: "Neg64F", argLength: 1}, 254 255 {name: "Com8", argLength: 1}, // ^arg0 256 {name: "Com16", argLength: 1}, 257 {name: "Com32", argLength: 1}, 258 {name: "Com64", argLength: 1}, 259 260 {name: "Ctz16", argLength: 1}, // Count trailing (low order) zeroes (returns 0-16) 261 {name: "Ctz32", argLength: 1}, // Count trailing zeroes (returns 0-32) 262 {name: "Ctz64", argLength: 1}, // Count trailing zeroes (returns 0-64) 263 264 {name: "Clz16", argLength: 1}, // Count leading (high order) zeroes (returns 0-16) 265 {name: "Clz32", argLength: 1}, // Count leading zeroes (returns 0-32) 266 {name: "Clz64", argLength: 1}, // Count leading zeroes (returns 0-64) 267 268 {name: "Bswap32", argLength: 1}, // Swap bytes 269 {name: "Bswap64", argLength: 1}, // Swap bytes 270 271 {name: "Sqrt", argLength: 1}, // sqrt(arg0), float64 only 272 273 // Data movement, max argument length for Phi is indefinite so just pick 274 // a really large number 275 {name: "Phi", argLength: -1}, // select an argument based on which predecessor block we came from 276 {name: "Copy", argLength: 1}, // output = arg0 277 // Convert converts between pointers and integers. 278 // We have a special op for this so as to not confuse GC 279 // (particularly stack maps). It takes a memory arg so it 280 // gets correctly ordered with respect to GC safepoints. 281 // arg0=ptr/int arg1=mem, output=int/ptr 282 {name: "Convert", argLength: 2}, 283 284 // constants. Constant values are stored in the aux or 285 // auxint fields. 286 {name: "ConstBool", aux: "Bool"}, // auxint is 0 for false and 1 for true 287 {name: "ConstString", aux: "String"}, // value is aux.(string) 288 {name: "ConstNil", typ: "BytePtr"}, // nil pointer 289 {name: "Const8", aux: "Int8"}, // auxint is sign-extended 8 bits 290 {name: "Const16", aux: "Int16"}, // auxint is sign-extended 16 bits 291 {name: "Const32", aux: "Int32"}, // auxint is sign-extended 32 bits 292 {name: "Const64", aux: "Int64"}, // value is auxint 293 {name: "Const32F", aux: "Float32"}, // value is math.Float64frombits(uint64(auxint)) and is exactly prepresentable as float 32 294 {name: "Const64F", aux: "Float64"}, // value is math.Float64frombits(uint64(auxint)) 295 {name: "ConstInterface"}, // nil interface 296 {name: "ConstSlice"}, // nil slice 297 298 // Constant-like things 299 {name: "InitMem"}, // memory input to the function. 300 {name: "Arg", aux: "SymOff"}, // argument to the function. aux=GCNode of arg, off = offset in that arg. 301 302 // The address of a variable. arg0 is the base pointer (SB or SP, depending 303 // on whether it is a global or stack variable). The Aux field identifies the 304 // variable. It will be either an *ExternSymbol (with arg0=SB), *ArgSymbol (arg0=SP), 305 // or *AutoSymbol (arg0=SP). 306 {name: "Addr", argLength: 1, aux: "Sym"}, // Address of a variable. Arg0=SP or SB. Aux identifies the variable. 307 308 {name: "SP"}, // stack pointer 309 {name: "SB", typ: "Uintptr"}, // static base pointer (a.k.a. globals pointer) 310 {name: "Func", aux: "Sym"}, // entry address of a function 311 312 // Memory operations 313 {name: "Load", argLength: 2}, // Load from arg0. arg1=memory 314 {name: "Store", argLength: 3, typ: "Mem", aux: "Int64"}, // Store arg1 to arg0. arg2=memory, auxint=size. Returns memory. 315 {name: "Move", argLength: 3, aux: "Int64"}, // arg0=destptr, arg1=srcptr, arg2=mem, auxint=size. Returns memory. 316 {name: "Zero", argLength: 2, aux: "Int64"}, // arg0=destptr, arg1=mem, auxint=size. Returns memory. 317 318 // Function calls. Arguments to the call have already been written to the stack. 319 // Return values appear on the stack. The method receiver, if any, is treated 320 // as a phantom first argument. 321 {name: "ClosureCall", argLength: 3, aux: "Int64"}, // arg0=code pointer, arg1=context ptr, arg2=memory. auxint=arg size. Returns memory. 322 {name: "StaticCall", argLength: 1, aux: "SymOff"}, // call function aux.(*gc.Sym), arg0=memory. auxint=arg size. Returns memory. 323 {name: "DeferCall", argLength: 1, aux: "Int64"}, // defer call. arg0=memory, auxint=arg size. Returns memory. 324 {name: "GoCall", argLength: 1, aux: "Int64"}, // go call. arg0=memory, auxint=arg size. Returns memory. 325 {name: "InterCall", argLength: 2, aux: "Int64"}, // interface call. arg0=code pointer, arg1=memory, auxint=arg size. Returns memory. 326 327 // Conversions: signed extensions, zero (unsigned) extensions, truncations 328 {name: "SignExt8to16", argLength: 1, typ: "Int16"}, 329 {name: "SignExt8to32", argLength: 1}, 330 {name: "SignExt8to64", argLength: 1}, 331 {name: "SignExt16to32", argLength: 1}, 332 {name: "SignExt16to64", argLength: 1}, 333 {name: "SignExt32to64", argLength: 1}, 334 {name: "ZeroExt8to16", argLength: 1, typ: "UInt16"}, 335 {name: "ZeroExt8to32", argLength: 1}, 336 {name: "ZeroExt8to64", argLength: 1}, 337 {name: "ZeroExt16to32", argLength: 1}, 338 {name: "ZeroExt16to64", argLength: 1}, 339 {name: "ZeroExt32to64", argLength: 1}, 340 {name: "Trunc16to8", argLength: 1}, 341 {name: "Trunc32to8", argLength: 1}, 342 {name: "Trunc32to16", argLength: 1}, 343 {name: "Trunc64to8", argLength: 1}, 344 {name: "Trunc64to16", argLength: 1}, 345 {name: "Trunc64to32", argLength: 1}, 346 347 {name: "Cvt32to32F", argLength: 1}, 348 {name: "Cvt32to64F", argLength: 1}, 349 {name: "Cvt64to32F", argLength: 1}, 350 {name: "Cvt64to64F", argLength: 1}, 351 {name: "Cvt32Fto32", argLength: 1}, 352 {name: "Cvt32Fto64", argLength: 1}, 353 {name: "Cvt64Fto32", argLength: 1}, 354 {name: "Cvt64Fto64", argLength: 1}, 355 {name: "Cvt32Fto64F", argLength: 1}, 356 {name: "Cvt64Fto32F", argLength: 1}, 357 358 // Automatically inserted safety checks 359 {name: "IsNonNil", argLength: 1, typ: "Bool"}, // arg0 != nil 360 {name: "IsInBounds", argLength: 2, typ: "Bool"}, // 0 <= arg0 < arg1. arg1 is guaranteed >= 0. 361 {name: "IsSliceInBounds", argLength: 2, typ: "Bool"}, // 0 <= arg0 <= arg1. arg1 is guaranteed >= 0. 362 {name: "NilCheck", argLength: 2, typ: "Void"}, // arg0=ptr, arg1=mem. Panics if arg0 is nil, returns void. 363 364 // Pseudo-ops 365 {name: "GetG", argLength: 1}, // runtime.getg() (read g pointer). arg0=mem 366 {name: "GetClosurePtr"}, // get closure pointer from dedicated register 367 368 // Indexing operations 369 {name: "ArrayIndex", aux: "Int64", argLength: 1}, // arg0=array, auxint=index. Returns a[i] 370 {name: "PtrIndex", argLength: 2}, // arg0=ptr, arg1=index. Computes ptr+sizeof(*v.type)*index, where index is extended to ptrwidth type 371 {name: "OffPtr", argLength: 1, aux: "Int64"}, // arg0 + auxint (arg0 and result are pointers) 372 373 // Slices 374 {name: "SliceMake", argLength: 3}, // arg0=ptr, arg1=len, arg2=cap 375 {name: "SlicePtr", argLength: 1, typ: "BytePtr"}, // ptr(arg0) 376 {name: "SliceLen", argLength: 1}, // len(arg0) 377 {name: "SliceCap", argLength: 1}, // cap(arg0) 378 379 // Complex (part/whole) 380 {name: "ComplexMake", argLength: 2}, // arg0=real, arg1=imag 381 {name: "ComplexReal", argLength: 1}, // real(arg0) 382 {name: "ComplexImag", argLength: 1}, // imag(arg0) 383 384 // Strings 385 {name: "StringMake", argLength: 2}, // arg0=ptr, arg1=len 386 {name: "StringPtr", argLength: 1, typ: "BytePtr"}, // ptr(arg0) 387 {name: "StringLen", argLength: 1, typ: "Int"}, // len(arg0) 388 389 // Interfaces 390 {name: "IMake", argLength: 2}, // arg0=itab, arg1=data 391 {name: "ITab", argLength: 1, typ: "BytePtr"}, // arg0=interface, returns itable field 392 {name: "IData", argLength: 1}, // arg0=interface, returns data field 393 394 // Structs 395 {name: "StructMake0"}, // Returns struct with 0 fields. 396 {name: "StructMake1", argLength: 1}, // arg0=field0. Returns struct. 397 {name: "StructMake2", argLength: 2}, // arg0,arg1=field0,field1. Returns struct. 398 {name: "StructMake3", argLength: 3}, // arg0..2=field0..2. Returns struct. 399 {name: "StructMake4", argLength: 4}, // arg0..3=field0..3. Returns struct. 400 {name: "StructSelect", argLength: 1, aux: "Int64"}, // arg0=struct, auxint=field index. Returns the auxint'th field. 401 402 // Spill&restore ops for the register allocator. These are 403 // semantically identical to OpCopy; they do not take/return 404 // stores like regular memory ops do. We can get away without memory 405 // args because we know there is no aliasing of spill slots on the stack. 406 {name: "StoreReg", argLength: 1}, 407 {name: "LoadReg", argLength: 1}, 408 409 // Used during ssa construction. Like Copy, but the arg has not been specified yet. 410 {name: "FwdRef", aux: "Sym"}, 411 412 // Unknown value. Used for Values whose values don't matter because they are dead code. 413 {name: "Unknown"}, 414 415 {name: "VarDef", argLength: 1, aux: "Sym", typ: "Mem"}, // aux is a *gc.Node of a variable that is about to be initialized. arg0=mem, returns mem 416 {name: "VarKill", argLength: 1, aux: "Sym"}, // aux is a *gc.Node of a variable that is known to be dead. arg0=mem, returns mem 417 {name: "VarLive", argLength: 1, aux: "Sym"}, // aux is a *gc.Node of a variable that must be kept live. arg0=mem, returns mem 418 {name: "KeepAlive", argLength: 2, typ: "Mem"}, // arg[0] is a value that must be kept alive until this mark. arg[1]=mem, returns mem 419 } 420 421 // kind control successors implicit exit 422 // ---------------------------------------------------------- 423 // Exit return mem [] yes 424 // Ret return mem [] yes 425 // RetJmp return mem [] yes 426 // Plain nil [next] 427 // If a boolean Value [then, else] 428 // Call mem [next] yes (control opcode should be OpCall or OpStaticCall) 429 // Check void [next] yes (control opcode should be Op{Lowered}NilCheck) 430 // First nil [always,never] 431 432 var genericBlocks = []blockData{ 433 {name: "Plain"}, // a single successor 434 {name: "If"}, // 2 successors, if control goto Succs[0] else goto Succs[1] 435 {name: "Call"}, // 1 successor, control is call op (of memory type) 436 {name: "Defer"}, // 2 successors, Succs[0]=defer queued, Succs[1]=defer recovered. control is call op (of memory type) 437 {name: "Check"}, // 1 successor, control is nilcheck op (of void type) 438 {name: "Ret"}, // no successors, control value is memory result 439 {name: "RetJmp"}, // no successors, jumps to b.Aux.(*gc.Sym) 440 {name: "Exit"}, // no successors, control value generates a panic 441 442 // transient block state used for dead code removal 443 {name: "First"}, // 2 successors, always takes the first one (second is dead) 444 } 445 446 func init() { 447 archs = append(archs, arch{ 448 name: "generic", 449 ops: genericOps, 450 blocks: genericBlocks, 451 generic: true, 452 }) 453 }