suckless/dwm - Unnamed repository; edit this file 'description' to name the repository.

diff options

Diffstat (limited to 'event.c')

0 files changed, 0 insertions, 0 deletions

# # # The Nim Compiler # (c) Copyright 2013 Andreas Rumpf # # See the file "copying.txt", included in this # distribution, for details about the copyright. # ## This module implements code generation for methods. import intsets, options, ast, msgs, idents, renderer, types, magicsys, sempass2, strutils, modulegraphs, lineinfos proc genConv(n: PNode, d: PType, downcast: bool; conf: ConfigRef): PNode = var dest = skipTypes(d, abstractPtrs) var source = skipTypes(n.typ, abstractPtrs) if (source.kind == tyObject) and (dest.kind == tyObject): var diff = inheritanceDiff(dest, source) if diff == high(int): # no subtype relation, nothing to do result = n elif diff < 0: result = newNodeIT(nkObjUpConv, n.info, d) result.add n if downcast: internalError(conf, n.info, "cgmeth.genConv: no upcast allowed") elif diff > 0: result = newNodeIT(nkObjDownConv, n.info, d) result.add n if not downcast: internalError(conf, n.info, "cgmeth.genConv: no downcast allowed") else: result = n else: result = n proc getDispatcher*(s: PSym): PSym = ## can return nil if is has no dispatcher. if dispatcherPos < s.ast.len: result = s.ast[dispatcherPos].sym doAssert sfDispatcher in result.flags proc methodCall*(n: PNode; conf: ConfigRef): PNode = result = n # replace ordinary method by dispatcher method: let disp = getDispatcher(result[0].sym) if disp != nil: result[0].sym = disp # change the arguments to up/downcasts to fit the dispatcher's parameters: for i in 1..<result.len: result[i] = genConv(result[i], disp.typ[i], true, conf) else: localError(conf, n.info, "'" & $result[0] & "' lacks a dispatcher") type MethodResult = enum No, Invalid, Yes proc sameMethodBucket(a, b: PSym; multiMethods: bool): MethodResult = if a.name.id != b.name.id: return if a.typ.len != b.typ.len: return for i in 1..<a.typ.len: var aa = a.typ[i] var bb = b.typ[i] while true: aa = skipTypes(aa, {tyGenericInst, tyAlias}) bb = skipTypes(bb, {tyGenericInst, tyAlias}) if aa.kind == bb.kind and aa.kind in {tyVar, tyPtr, tyRef, tyLent}: aa = aa.lastSon bb = bb.lastSon else: break if sameType(a.typ[i], b.typ[i]): if aa.kind == tyObject and result != Invalid: result = Yes elif aa.kind == tyObject and bb.kind == tyObject and (i == 1 or multiMethods): let diff = inheritanceDiff(bb, aa) if diff < 0: if result != Invalid: result = Yes else: return No elif diff != high(int) and sfFromGeneric notin (a.flags+b.flags): result = Invalid else: return No else: return No if result == Yes: # check for return type: if not sameTypeOrNil(a.typ[0], b.typ[0]): if b.typ[0] != nil and b.typ[0].kind == tyUntyped: # infer 'auto' from the base to make it consistent: b.typ[0] = a.typ[0] else: return No proc attachDispatcher(s: PSym, dispatcher: PNode) = if dispatcherPos < s.ast.len: # we've added a dispatcher already, so overwrite it s.ast[dispatcherPos] = dispatcher else: setLen(s.ast.sons, dispatcherPos+1) if s.ast[resultPos] == nil: s.ast[resultPos] = newNodeI(nkEmpty, s.info) s.ast[dispatcherPos] = dispatcher proc createDispatcher(s: PSym; idgen: IdGenerator): PSym = var disp = copySym(s, nextId(idgen)) incl(disp.flags, sfDispatcher) excl(disp.flags, sfExported) disp.typ = copyType(disp.typ, nextId(idgen), disp.typ.owner) # we can't inline the dispatcher itself (for now): if disp.typ.callConv == ccInline: disp.typ.callConv = ccNimCall disp.ast = copyTree(s.ast) disp.ast[bodyPos] = newNodeI(nkEmpty, s.info) disp.loc.r = nil if s.typ[0] != nil: if disp.ast.len > resultPos: disp.ast[resultPos].sym = copySym(s.ast[resultPos].sym, nextId(idgen)) else: # We've encountered a method prototype without a filled-in # resultPos slot. We put a placeholder in there that will # be updated in fixupDispatcher(). disp.ast.add newNodeI(nkEmpty, s.info) attachDispatcher(s, newSymNode(disp)) # attach to itself to prevent bugs: attachDispatcher(disp, newSymNode(disp)) return disp proc fixupDispatcher(meth, disp: PSym; conf: ConfigRef) = # We may have constructed the dispatcher from a method prototype # and need to augment the incomplete dispatcher with information # from later definitions, particularly the resultPos slot. Also, # the lock level of the dispatcher needs to be updated/checked # against that of the method. if disp.ast.len > resultPos and meth.ast.len > resultPos and disp.ast[resultPos].kind == nkEmpty: disp.ast[resultPos] = copyTree(meth.ast[resultPos]) # The following code works only with lock levels, so we disable # it when they're not available. when declared(TLockLevel): proc `<`(a, b: TLockLevel): bool {.borrow.} proc `==`(a, b: TLockLevel): bool {.borrow.} if disp.typ.lockLevel == UnspecifiedLockLevel: disp.typ.lockLevel = meth.typ.lockLevel elif meth.typ.lockLevel != UnspecifiedLockLevel and meth.typ.lockLevel != disp.typ.lockLevel: message(conf, meth.info, warnLockLevel, "method has lock level $1, but another method has $2" % [$meth.typ.lockLevel, $disp.typ.lockLevel]) # XXX The following code silences a duplicate warning in # checkMethodeffects() in sempass2.nim for now. if disp.typ.lockLevel < meth.typ.lockLevel: disp.typ.lockLevel = meth.typ.lockLevel proc methodDef*(g: ModuleGraph; idgen: IdGenerator; s: PSym, fromCache: bool) = var witness: PSym for i in 0..<g.methods.len: let disp = g.methods[i].dispatcher case sameMethodBucket(disp, s, multimethods = optMultiMethods in g.config.globalOptions) of Yes: g.methods[i].methods.add(s) attachDispatcher(s, disp.ast[dispatcherPos]) fixupDispatcher(s, disp, g.config) #echo "fixup ", disp.name.s, " ", disp.id when useEffectSystem: checkMethodEffects(g, disp, s) if {sfBase, sfFromGeneric} * s.flags == {sfBase} and g.methods[i].methods[0] != s: # already exists due to forwarding definition? localError(g.config, s.info, "method is not a base") return of No: discard of Invalid: if witness.isNil: witness = g.methods[i].methods[0] # create a new dispatcher: g.methods.add((methods: @[s], dispatcher: createDispatcher(s, idgen))) #echo "adding ", s.info #if fromCache: # internalError(s.info, "no method dispatcher found") if witness != nil: localError(g.config, s.info, "invalid declaration order; cannot attach '" & s.name.s & "' to method defined here: " & g.config$witness.info) elif sfBase notin s.flags: message(g.config, s.info, warnUseBase) proc relevantCol(methods: seq[PSym], col: int): bool = # returns true iff the position is relevant var t = methods[0].typ[col].skipTypes(skipPtrs) if t.kind == tyObject: for i in 1..high(methods): let t2 = skipTypes(methods[i].typ[col], skipPtrs) if not sameType(t2, t): return true proc cmpSignatures(a, b: PSym, relevantCols: IntSet): int = for col in 1..<a.typ.len: if contains(relevantCols, col): var aa = skipTypes(a.typ[col], skipPtrs) var bb = skipTypes(b.typ[col], skipPtrs) var d = inheritanceDiff(aa, bb) if (d != high(int)) and d != 0: return d proc sortBucket(a: var seq[PSym], relevantCols: IntSet) = # we use shellsort here; fast and simple var n = a.len var h = 1 while true: h = 3 * h + 1 if h > n: break while true: h = h div 3 for i in h..<n: var v = a[i] var j = i while cmpSignatures(a[j - h], v, relevantCols) >= 0: a[j] = a[j - h] j = j - h if j < h: break a[j] = v if h == 1: break proc genDispatcher(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet): PSym = var base = methods[0].ast[dispatcherPos].sym result = base var paramLen = base.typ.len var nilchecks = newNodeI(nkStmtList, base.info) var disp = newNodeI(nkIfStmt, base.info) var ands = getSysMagic(g, unknownLineInfo, "and", mAnd) var iss = getSysMagic(g, unknownLineInfo, "of", mOf) let boolType = getSysType(g, unknownLineInfo, tyBool) for col in 1..<paramLen: if contains(relevantCols, col): let param = base.typ.n[col].sym if param.typ.skipTypes(abstractInst).kind in {tyRef, tyPtr}: nilchecks.add newTree(nkCall, newSymNode(getCompilerProc(g, "chckNilDisp")), newSymNode(param)) for meth in 0..high(methods): var curr = methods[meth] # generate condition: var cond: PNode = nil for col in 1..<paramLen: if contains(relevantCols, col): var isn = newNodeIT(nkCall, base.info, boolType) isn.add newSymNode(iss) let param = base.typ.n[col].sym isn.add newSymNode(param) isn.add newNodeIT(nkType, base.info, curr.typ[col]) if cond != nil: var a = newNodeIT(nkCall, base.info, boolType) a.add newSymNode(ands) a.add cond a.add isn cond = a else: cond = isn let retTyp = base.typ[0] let call = newNodeIT(nkCall, base.info, retTyp) call.add newSymNode(curr) for col in 1..<paramLen: call.add genConv(newSymNode(base.typ.n[col].sym), curr.typ[col], false, g.config) var ret: PNode if retTyp != nil: var a = newNodeI(nkFastAsgn, base.info) a.add newSymNode(base.ast[resultPos].sym) a.add call ret = newNodeI(nkReturnStmt, base.info) ret.add a else: ret = call if cond != nil: var a = newNodeI(nkElifBranch, base.info) a.add cond a.add ret disp.add a else: disp = ret nilchecks.add disp nilchecks.flags.incl nfTransf # should not be further transformed result.ast[bodyPos] = nilchecks proc generateMethodDispatchers*(g: ModuleGraph): PNode = result = newNode(nkStmtList) for bucket in 0..<g.methods.len: var relevantCols = initIntSet() for col in 1..<g.methods[bucket].methods[0].typ.len: if relevantCol(g.methods[bucket].methods, col): incl(relevantCols, col) if optMultiMethods notin g.config.globalOptions: # if multi-methods are not enabled, we are interested only in the first field break sortBucket(g.methods[bucket].methods, relevantCols) result.add newSymNode(genDispatcher(g, g.methods[bucket].methods, relevantCols))


context:
space:
mode: