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13pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
span.linenos { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
.highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.highlight .k { color: #008800; font-weight: bold } /* Keyword */
.highlight .ch { color: #888888 } /* Comment.Hashbang */
.highlight .cm { color: #888888 } /* Comment.Multiline */
.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1 { color: #888888 } /* Comment.Single */
.highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .ges { font-weight: bold; font-style: italic } /* Generic.EmphStrong */
.highlight .gr { color: #aa0000 } /* Generic.Error */
.highlight .gh { color: #333333 } /* Generic.Heading */
.highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.highlight .go { color: #888888 } /* Generic.Output */
.highlight .gp { color: #555555 } /* Generic.Prompt */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #666666 } /* Generic.Subheading */
.highlight .gt { color: #aa0000 } /* Generic.Traceback */
.highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.highlight .kp { color: #008800 } /* Keyword.Pseudo */
.highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.highlight .na { color: #336699 } /* Name.Attribute */
.highlight .nb { color: #003388 } /* Name.Builtin */
.highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.highlight .no { color: #003366; font-weight: bold } /* Name.Constant */
.highlight .nd { color: #555555 } /* Name.Decorator */
.highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.highlight .nl { color: #336699; font-style: italic } /* Name.Label */
.highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.highlight .py { color: #336699; font-weight: bold } /* Name.Property */
.highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.highlight .nv { color: #336699 } /* Name.Variable */
.highlight .ow { color: #008800 } /* Operator.Word */
.highlight .w { color: #bbbbbb } /* Text.Whitespace */
.highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */
.highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */
.highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */
.highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #336699 } /* Name.Variable.Class */
.highlight .vg { color: #dd7700 } /* Name.Variable.Global */
.highlight .vi { color: #3333bb } /* Name.Variable.Instance */
.highlight .vm { color: #336699 } /* Name.Variable.Magic */
.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
#!/bin/sh
# Translate given Mu files with debug information on Linux.
#
# (You _could_ do something similar on other platforms using emulation. But I
# often find that to be too slow.)

set -e

cat $* [0-9]*.mu    |apps/mu    > a.subx

./translate_subx_debug init.linux [0-9]*.subx mu-init.subx a.subx
' href='#n214'>214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412
#
#
#           The Nim Compiler
#        (c) Copyright 2015 Andreas Rumpf
#
#    See the file "copying.txt", included in this
#    distribution, for details about the copyright.
#

# This include file implements the semantic checking for magics.
# included from sem.nim

proc semAddr(c: PContext; n: PNode; isUnsafeAddr=false): PNode =
  result = newNodeI(nkAddr, n.info)
  let x = semExprWithType(c, n)
  if x.kind == nkSym:
    x.sym.flags.incl(sfAddrTaken)
  if isAssignable(c, x, isUnsafeAddr) notin {arLValue, arLocalLValue}:
    localError(c.config, n.info, errExprHasNoAddress)
  result.add x
  result.typ = makePtrType(c, x.typ)

proc semTypeOf(c: PContext; n: PNode): PNode =
  var m = BiggestInt 1 # typeOfIter
  if n.len == 3:
    let mode = semConstExpr(c, n[2])
    if mode.kind != nkIntLit:
      localError(c.config, n.info, "typeof: cannot evaluate 'mode' parameter at compile-time")
    else:
      m = mode.intVal
  result = newNodeI(nkTypeOfExpr, n.info)
  let typExpr = semExprWithType(c, n[1], if m == 1: {efInTypeof} else: {})
  result.add typExpr
  result.typ = makeTypeDesc(c, typExpr.typ)

type
  SemAsgnMode = enum asgnNormal, noOverloadedSubscript, noOverloadedAsgn

proc semAsgn(c: PContext, n: PNode; mode=asgnNormal): PNode
proc semSubscript(c: PContext, n: PNode, flags: TExprFlags): PNode

proc skipAddr(n: PNode): PNode {.inline.} =
  (if n.kind == nkHiddenAddr: n.sons[0] else: n)

proc semArrGet(c: PContext; n: PNode; flags: TExprFlags): PNode =
  result = newNodeI(nkBracketExpr, n.info)
  for i in 1..<n.len: result.add(n[i])
  result = semSubscript(c, result, flags)
  if result.isNil:
    let x = copyTree(n)
    x.sons[0] = newIdentNode(getIdent(c.cache, "[]"), n.info)
    bracketNotFoundError(c, x)
    #localError(c.config, n.info, "could not resolve: " & $n)
    result = n

proc semArrPut(c: PContext; n: PNode; flags: TExprFlags): PNode =
  # rewrite `[]=`(a, i, x)  back to ``a[i] = x``.
  let b = newNodeI(nkBracketExpr, n.info)
  b.add(n[1].skipAddr)
  for i in 2..n.len-2: b.add(n[i])
  result = newNodeI(nkAsgn, n.info, 2)
  result.sons[0] = b
  result.sons[1] = n.lastSon
  result = semAsgn(c, result, noOverloadedSubscript)

proc semAsgnOpr(c: PContext; n: PNode): PNode =
  result = newNodeI(nkAsgn, n.info, 2)
  result.sons[0] = n[1]
  result.sons[1] = n[2]
  result = semAsgn(c, result, noOverloadedAsgn)

proc semIsPartOf(c: PContext, n: PNode, flags: TExprFlags): PNode =
  var r = isPartOf(n[1], n[2])
  result = newIntNodeT(ord(r), n, c.graph)

proc expectIntLit(c: PContext, n: PNode): int =
  let x = c.semConstExpr(c, n)
  case x.kind
  of nkIntLit..nkInt64Lit: result = int(x.intVal)
  else: localError(c.config, n.info, errIntLiteralExpected)

proc semInstantiationInfo(c: PContext, n: PNode): PNode =
  result = newNodeIT(nkTupleConstr, n.info, n.typ)
  let idx = expectIntLit(c, n.sons[1])
  let useFullPaths = expectIntLit(c, n.sons[2])
  let info = getInfoContext(c.config, idx)
  var filename = newNodeIT(nkStrLit, n.info, getSysType(c.graph, n.info, tyString))
  filename.strVal = if useFullPaths != 0: toFullPath(c.config, info) else: toFilename(c.config, info)
  var line = newNodeIT(nkIntLit, n.info, getSysType(c.graph, n.info, tyInt))
  line.intVal = toLinenumber(info)
  var column = newNodeIT(nkIntLit, n.info, getSysType(c.graph, n.info, tyInt))
  column.intVal = toColumn(info)
  result.add(filename)
  result.add(line)
  result.add(column)

proc toNode(t: PType, i: TLineInfo): PNode =
  result = newNodeIT(nkType, i, t)

const
  # these are types that use the bracket syntax for instantiation
  # they can be subjected to the type traits `genericHead` and
  # `Uninstantiated`
  tyUserDefinedGenerics* = {tyGenericInst, tyGenericInvocation,
                            tyUserTypeClassInst}

  tyMagicGenerics* = {tySet, tySequence, tyArray, tyOpenArray}

  tyGenericLike* = tyUserDefinedGenerics +
                   tyMagicGenerics +
                   {tyCompositeTypeClass}

proc uninstantiate(t: PType): PType =
  result = case t.kind
    of tyMagicGenerics: t
    of tyUserDefinedGenerics: t.base
    of tyCompositeTypeClass: uninstantiate t.sons[1]
    else: t

proc evalTypeTrait(c: PContext; traitCall: PNode, operand: PType, context: PSym): PNode =
  const skippedTypes = {tyTypeDesc, tyAlias, tySink}
  let trait = traitCall[0]
  internalAssert c.config, trait.kind == nkSym
  var operand = operand.skipTypes(skippedTypes)

  template operand2: PType =
    traitCall.sons[2].typ.skipTypes({tyTypeDesc})

  template typeWithSonsResult(kind, sons): PNode =
    newTypeWithSons(context, kind, sons).toNode(traitCall.info)

  case trait.sym.name.s
  of "or", "|":
    return typeWithSonsResult(tyOr, @[operand, operand2])
  of "and":
    return typeWithSonsResult(tyAnd, @[operand, operand2])
  of "not":
    return typeWithSonsResult(tyNot, @[operand])
  of "name":
    result = newStrNode(nkStrLit, operand.typeToString(preferTypeName))
    result.typ = newType(tyString, context)
    result.info = traitCall.info
  of "arity":
    result = newIntNode(nkIntLit, operand.len - ord(operand.kind==tyProc))
    result.typ = newType(tyInt, context)
    result.info = traitCall.info
  of "genericHead":
    var res = uninstantiate(operand)
    if res == operand and res.kind notin tyMagicGenerics:
      localError(c.config, traitCall.info,
        "genericHead expects a generic type. The given type was " &
        typeToString(operand))
      return newType(tyError, context).toNode(traitCall.info)
    result = res.base.toNode(traitCall.info)
  of "stripGenericParams":
    result = uninstantiate(operand).toNode(traitCall.info)
  of "supportsCopyMem":
    let t = operand.skipTypes({tyVar, tyLent, tyGenericInst, tyAlias, tySink, tyInferred})
    let complexObj = containsGarbageCollectedRef(t) or
                     hasDestructor(t)
    result = newIntNodeT(ord(not complexObj), traitCall, c.graph)
  else:
    localError(c.config, traitCall.info, "unknown trait")
    result = newNodeI(nkEmpty, traitCall.info)

proc semTypeTraits(c: PContext, n: PNode): PNode =
  checkMinSonsLen(n, 2, c.config)
  let t = n.sons[1].typ
  internalAssert c.config, t != nil and t.kind == tyTypeDesc
  if t.sonsLen > 0:
    # This is either a type known to sem or a typedesc
    # param to a regular proc (again, known at instantiation)
    result = evalTypeTrait(c, n, t, getCurrOwner(c))
  else:
    # a typedesc variable, pass unmodified to evals
    result = n

proc semOrd(c: PContext, n: PNode): PNode =
  result = n
  let parType = n.sons[1].typ
  if isOrdinalType(parType, allowEnumWithHoles=true):
    discard
  elif parType.kind == tySet:
    result.typ = makeRangeType(c, firstOrd(c.config, parType), lastOrd(c.config, parType), n.info)
  else:
    localError(c.config, n.info, errOrdinalTypeExpected)
    result.typ = errorType(c)

proc semBindSym(c: PContext, n: PNode): PNode =
  result = copyNode(n)
  result.add(n.sons[0])

  let sl = semConstExpr(c, n.sons[1])
  if sl.kind notin {nkStrLit, nkRStrLit, nkTripleStrLit}:
    localError(c.config, n.sons[1].info, errStringLiteralExpected)
    return errorNode(c, n)

  let isMixin = semConstExpr(c, n.sons[2])
  if isMixin.kind != nkIntLit or isMixin.intVal < 0 or
      isMixin.intVal > high(TSymChoiceRule).int:
    localError(c.config, n.sons[2].info, errConstExprExpected)
    return errorNode(c, n)

  let id = newIdentNode(getIdent(c.cache, sl.strVal), n.info)
  let s = qualifiedLookUp(c, id, {checkUndeclared})
  if s != nil:
    # we need to mark all symbols:
    var sc = symChoice(c, id, s, TSymChoiceRule(isMixin.intVal))
    if not (c.inStaticContext > 0 or getCurrOwner(c).isCompileTimeProc):
      # inside regular code, bindSym resolves to the sym-choice
      # nodes (see tinspectsymbol)
      return sc
    result.add(sc)
  else:
    errorUndeclaredIdentifier(c, n.sons[1].info, sl.strVal)

proc opBindSym(c: PContext, scope: PScope, n: PNode, isMixin: int, info: PNode): PNode =
  if n.kind notin {nkStrLit, nkRStrLit, nkTripleStrLit, nkIdent}:
    localError(c.config, info.info, errStringOrIdentNodeExpected)
    return errorNode(c, n)

  if isMixin < 0 or isMixin > high(TSymChoiceRule).int:
    localError(c.config, info.info, errConstExprExpected)
    return errorNode(c, n)

  let id = if n.kind == nkIdent: n
    else: newIdentNode(getIdent(c.cache, n.strVal), info.info)

  let tmpScope = c.currentScope
  c.currentScope = scope
  let s = qualifiedLookUp(c, id, {checkUndeclared})
  if s != nil:
    # we need to mark all symbols:
    result = symChoice(c, id, s, TSymChoiceRule(isMixin))
  else:
    errorUndeclaredIdentifier(c, info.info, if n.kind == nkIdent: n.ident.s
      else: n.strVal)
  c.currentScope = tmpScope

proc semDynamicBindSym(c: PContext, n: PNode): PNode =
  # inside regular code, bindSym resolves to the sym-choice
  # nodes (see tinspectsymbol)
  if not (c.inStaticContext > 0 or getCurrOwner(c).isCompileTimeProc):
    return semBindSym(c, n)

  if c.graph.vm.isNil:
    setupGlobalCtx(c.module, c.graph)

  let
    vm = PCtx c.graph.vm
    # cache the current scope to
    # prevent it lost into oblivion
    scope = c.currentScope

  # cannot use this
  # vm.config.features.incl dynamicBindSym

  proc bindSymWrapper(a: VmArgs) =
    # capture PContext and currentScope
    # param description:
    #   0. ident, a string literal / computed string / or ident node
    #   1. bindSym rule
    #   2. info node
    a.setResult opBindSym(c, scope, a.getNode(0), a.getInt(1).int, a.getNode(2))

  let
    # altough we use VM callback here, it is not
    # executed like 'normal' VM callback
    idx = vm.registerCallback("bindSymImpl", bindSymWrapper)
    # dummy node to carry idx information to VM
    idxNode = newIntTypeNode(nkIntLit, idx, c.graph.getSysType(TLineInfo(), tyInt))

  result = copyNode(n)
  for x in n: result.add x
  result.add n # info node
  result.add idxNode

proc semShallowCopy(c: PContext, n: PNode, flags: TExprFlags): PNode

proc semOf(c: PContext, n: PNode): PNode =
  if sonsLen(n) == 3:
    n.sons[1] = semExprWithType(c, n.sons[1])
    n.sons[2] = semExprWithType(c, n.sons[2], {efDetermineType})
    #restoreOldStyleType(n.sons[1])
    #restoreOldStyleType(n.sons[2])
    let a = skipTypes(n.sons[1].typ, abstractPtrs)
    let b = skipTypes(n.sons[2].typ, abstractPtrs)
    let x = skipTypes(n.sons[1].typ, abstractPtrs-{tyTypeDesc})
    let y = skipTypes(n.sons[2].typ, abstractPtrs-{tyTypeDesc})

    if x.kind == tyTypeDesc or y.kind != tyTypeDesc:
      localError(c.config, n.info, "'of' takes object types")
    elif b.kind != tyObject or a.kind != tyObject:
      localError(c.config, n.info, "'of' takes object types")
    else:
      let diff = inheritanceDiff(a, b)
      # | returns: 0 iff `a` == `b`
      # | returns: -x iff `a` is the x'th direct superclass of `b`
      # | returns: +x iff `a` is the x'th direct subclass of `b`
      # | returns: `maxint` iff `a` and `b` are not compatible at all
      if diff <= 0:
        # optimize to true:
        message(c.config, n.info, hintConditionAlwaysTrue, renderTree(n))
        result = newIntNode(nkIntLit, 1)
        result.info = n.info
        result.typ = getSysType(c.graph, n.info, tyBool)
        return result
      elif diff == high(int):
        if commonSuperclass(a, b) == nil:
          localError(c.config, n.info, "'$1' cannot be of this subtype" % typeToString(a))
        else:
          message(c.config, n.info, hintConditionAlwaysFalse, renderTree(n))
          result = newIntNode(nkIntLit, 0)
          result.info = n.info
          result.typ = getSysType(c.graph, n.info, tyBool)
  else:
    localError(c.config, n.info, "'of' takes 2 arguments")
  n.typ = getSysType(c.graph, n.info, tyBool)
  result = n

proc magicsAfterOverloadResolution(c: PContext, n: PNode,
                                   flags: TExprFlags): PNode =
  ## This is the preferred code point to implement magics.
  ## ``c`` the current module, a symbol table to a very good approximation
  ## ``n`` the ast like it would be passed to a real macro
  ## ``flags`` Some flags for more contextual information on how the
  ## "macro" is calld.

  case n[0].sym.magic
  of mAddr:
    checkSonsLen(n, 2, c.config)
    result = semAddr(c, n.sons[1], n[0].sym.name.s == "unsafeAddr")
  of mTypeOf:
    result = semTypeOf(c, n)
  of mSizeOf:
    # TODO there is no proper way to find out if a type cannot be queried for the size.
    let size = getSize(c.config, n[1].typ)
    # We just assume here that the type might come from the c backend
    if size == szUnknownSize:
      # Forward to the c code generation to emit a `sizeof` in the C code.
      result = n
    elif size >= 0:
      result = newIntNode(nkIntLit, size)
      result.info = n.info
      result.typ = n.typ
    else:
      localError(c.config, n.info, "cannot evaluate 'sizeof' because its type is not defined completely, type: " & n[1].typ.typeToString)
      result = n
  of mAlignOf:
    result = newIntNode(nkIntLit, getAlign(c.config, n[1].typ))
    result.info = n.info
    result.typ = n.typ
  of mOffsetOf:
    var dotExpr: PNode

    block findDotExpr:
      if n[1].kind == nkDotExpr:
        dotExpr = n[1]
      elif n[1].kind == nkCheckedFieldExpr:
        dotExpr = n[1][0]
      else:
        illFormedAst(n, c.config)

    assert dotExpr != nil

    let value = dotExpr[0]
    let member = dotExpr[1]

    discard computeSize(c.config, value.typ)

    result = newIntNode(nkIntLit, member.sym.offset)
    result.info = n.info
    result.typ = n.typ
  of mArrGet:
    result = semArrGet(c, n, flags)
  of mArrPut:
    result = semArrPut(c, n, flags)
  of mAsgn:
    if n[0].sym.name.s == "=":
      result = semAsgnOpr(c, n)
    else:
      result = semShallowCopy(c, n, flags)
  of mIsPartOf: result = semIsPartOf(c, n, flags)
  of mTypeTrait: result = semTypeTraits(c, n)
  of mAstToStr:
    result = newStrNodeT(renderTree(n[1], {renderNoComments}), n, c.graph)
    result.typ = getSysType(c.graph, n.info, tyString)
  of mInstantiationInfo: result = semInstantiationInfo(c, n)
  of mOrd: result = semOrd(c, n)
  of mOf: result = semOf(c, n)
  of mHigh, mLow: result = semLowHigh(c, n, n[0].sym.magic)
  of mShallowCopy: result = semShallowCopy(c, n, flags)
  of mNBindSym:
    if dynamicBindSym notin c.features:
      result = semBindSym(c, n)
    else:
      result = semDynamicBindSym(c, n)
  of mProcCall:
    result = n
    result.typ = n[1].typ
  of mDotDot:
    result = n
  of mRoof:
    localError(c.config, n.info, "builtin roof operator is not supported anymore")
  of mPlugin:
    let plugin = getPlugin(c.cache, n[0].sym)
    if plugin.isNil:
      localError(c.config, n.info, "cannot find plugin " & n[0].sym.name.s)
      result = n
    else:
      result = plugin(c, n)
  else: result = n