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author | Araq <rumpf_a@web.de> | 2014-09-21 18:39:00 +0200 |
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committer | Araq <rumpf_a@web.de> | 2014-09-21 18:39:00 +0200 |
commit | 7916b1f9aa93fca368afda8b18396230ac7f338c (patch) | |
tree | 04072aeee4ae211b91c088a7267455b82daf9787 /compiler/sempass2.nim | |
parent | 4800acf6ab92799316b270c991b6e8c01454608f (diff) | |
download | Nim-7916b1f9aa93fca368afda8b18396230ac7f338c.tar.gz |
implemented 'guard' annotation
Diffstat (limited to 'compiler/sempass2.nim')
-rw-r--r-- | compiler/sempass2.nim | 134 |
1 files changed, 85 insertions, 49 deletions
diff --git a/compiler/sempass2.nim b/compiler/sempass2.nim index fee70af15..794b7ec80 100644 --- a/compiler/sempass2.nim +++ b/compiler/sempass2.nim @@ -57,9 +57,13 @@ discard """ c() --> we need a stack of scopes for this analysis -""" -const trackGlobals = false ## we don't need it for now + # XXX enhance the algorithm to care about 'dirty' expressions: + lock a[i].L: + inc i # mark 'i' dirty + lock a[j].L: + access a[i], a[j] # --> reject a[i] +""" type TEffects = object @@ -71,12 +75,69 @@ type init: seq[int] # list of initialized variables guards: TModel # nested guards locked: seq[PNode] # locked locations - gcUnsafe, isRecursive: bool + gcUnsafe, isRecursive, isToplevel: bool PEffects = var TEffects proc isLocalVar(a: PEffects, s: PSym): bool = s.kind in {skVar, skResult} and sfGlobal notin s.flags and s.owner == a.owner +proc lockLocations(a: PEffects; pragma: PNode) = + if pragma.kind != nkExprColonExpr: + internalError(pragma.info, "no colon") + return + for x in pragma[1]: + a.locked.add x + +proc guardGlobal(a: PEffects; n: PNode; guard: PSym) = + # check whether the corresponding lock is held: + for L in a.locked: + if L.kind == nkSym and L.sym == guard: return + # we allow accesses nevertheless in top level statements for + # easier initialization: + #if a.isTopLevel: + # message(n.info, warnUnguardedAccess, renderTree(n)) + #else: + if not a.isTopLevel: + localError(n.info, errGenerated, "unguarded access: " & renderTree(n)) + +# 'guard*' are checks which are concerned with 'guard' annotations +# (var x{.guard: y.}: int) +proc guardDotAccess(a: PEffects; n: PNode) = + let ri = n.sons[1] + internalAssert ri.kind == nkSym and ri.sym.kind == skField + var g = ri.sym.guard + if g.isNil or a.isTopLevel: return + # fixup guard: + if g.kind == skUnknown: + var field: PSym = nil + var ty = n.sons[0].typ.skipTypes(abstractPtrs) + if ty.kind == tyTuple: + field = lookupInRecord(ty.n, g.name) + else: + while ty != nil and ty.kind == tyObject: + field = lookupInRecord(ty.n, g.name) + if field != nil: break + ty = ty.sons[0] + if ty == nil: break + ty = ty.skipTypes(abstractPtrs) + if field == nil: + localError(n.info, errGenerated, "invalid guard field: " & g.name.s) + return + g = field + #ri.sym.guard = field + # XXX unfortunately this is not correct for generic instantiations! + if g.kind == skField: + let dot = newNodeI(nkDotExpr, n.info, 2) + dot.sons[0] = n.sons[0] + dot.sons[1] = newSymNode(g) + dot.typ = g.typ + for L in a.locked: + #if a.guards.sameSubexprs(dot, L): return + if guards.sameTree(dot, L): return + localError(n.info, errGenerated, "unguarded access: " & renderTree(n)) + else: + guardGlobal(a, n, g) + proc initVar(a: PEffects, n: PNode) = if n.kind != nkSym: return let s = n.sym @@ -93,13 +154,6 @@ proc initVarViaNew(a: PEffects, n: PNode) = # are initialized: initVar(a, n) -when trackGlobals: - proc addUse(a: PEffects, e: PNode) = - var aa = a.uses - for i in 0 .. <aa.len: - if aa[i].sym.id == e.sym.id: return - a.uses.add(e) - proc useVar(a: PEffects, n: PNode) = let s = n.sym if isLocalVar(a, s): @@ -110,9 +164,8 @@ proc useVar(a: PEffects, n: PNode) = message(n.info, warnUninit, s.name.s) # prevent superfluous warnings about the same variable: a.init.add s.id - if {sfGlobal, sfThread} * s.flags == {sfGlobal} and s.kind == skVar: - when trackGlobals: - a.addUse(copyNode(n)) + if {sfGlobal, sfThread} * s.flags == {sfGlobal} and s.kind in {skVar, skLet}: + if s.guard != nil: guardGlobal(a, n, s.guard) if (tfHasGCedMem in s.typ.flags or s.typ.isGCedMem) and tfGcSafe notin s.typ.flags: if warnGcUnsafe in gNotes: message(n.info, warnGcUnsafe, renderTree(n)) @@ -186,13 +239,6 @@ proc mergeTags(a: PEffects, b, comesFrom: PNode) = else: for effect in items(b): addTag(a, effect, useLineInfo=comesFrom != nil) -when trackGlobals: - proc mergeUses(a: PEffects, b, comesFrom: PNode) = - if b.isNil: - addUse(a, createAnyGlobal(comesFrom)) - else: - for effect in items(b): addUse(a, effect) - proc listEffects(a: PEffects) = for e in items(a.exc): message(e.info, hintUser, typeToString(e.typ)) for e in items(a.tags): message(e.info, hintUser, typeToString(e.typ)) @@ -322,7 +368,7 @@ proc documentRaises*(n: PNode) = if n.sons[namePos].kind != nkSym: return documentEffect(n, n.sons[pragmasPos], wRaises, exceptionEffects) documentEffect(n, n.sons[pragmasPos], wTags, tagEffects) - documentEffect(n, n.sons[pragmasPos], wUses, usesEffects) + #documentEffect(n, n.sons[pragmasPos], wUses, usesEffects) template notGcSafe(t): expr = {tfGcSafe, tfNoSideEffect} * t.flags == {} @@ -342,10 +388,6 @@ proc propagateEffects(tracked: PEffects, n: PNode, s: PSym) = if warnGcUnsafe in gNotes: message(n.info, warnGcUnsafe, renderTree(n)) tracked.gcUnsafe = true - when trackGlobals: - let usesSpec = effectSpec(pragma, wUses) - mergeUses(tracked, usesSpec, n) - proc notNilCheck(tracked: PEffects, n: PNode, paramType: PType) = let n = n.skipConv if paramType != nil and tfNotNil in paramType.flags and @@ -381,7 +423,6 @@ proc trackOperand(tracked: PEffects, n: PNode, paramType: PType) = # we have no explicit effects so assume the worst: addEffect(tracked, createRaise(n)) addTag(tracked, createTag(n)) - when trackGlobals: addUse(tracked, createAnyGlobal(n)) # assume GcUnsafe unless in its type; 'forward' does not matter: if notGcSafe(op): if warnGcUnsafe in gNotes: message(n.info, warnGcUnsafe, renderTree(n)) @@ -389,7 +430,6 @@ proc trackOperand(tracked: PEffects, n: PNode, paramType: PType) = else: mergeEffects(tracked, effectList.sons[exceptionEffects], n) mergeTags(tracked, effectList.sons[tagEffects], n) - when trackGlobals: mergeUses(tracked, effectList.sons[usesEffects], n) if notGcSafe(op): if warnGcUnsafe in gNotes: message(n.info, warnGcUnsafe, renderTree(n)) tracked.gcUnsafe = true @@ -529,12 +569,9 @@ proc track(tracked: PEffects, n: PNode) = elif isIndirectCall(a, tracked.owner): addEffect(tracked, createRaise(n)) addTag(tracked, createTag(n)) - when trackGlobals: addUse(tracked, createAnyGlobal(n)) - # XXX handle 'gcsafe' properly for callbacks! else: mergeEffects(tracked, effectList.sons[exceptionEffects], n) mergeTags(tracked, effectList.sons[tagEffects], n) - when trackGlobals: mergeUses(tracked, effectList.sons[usesEffects], n) if notGcSafe(op) and not importedFromC(a): # and it's not a recursive call: if not (a.kind == nkSym and a.sym == tracked.owner): @@ -546,6 +583,9 @@ proc track(tracked: PEffects, n: PNode) = initVarViaNew(tracked, n.sons[1]) for i in 0 .. <safeLen(n): track(tracked, n.sons[i]) + of nkDotExpr: + guardDotAccess(tracked, n) + for i in 0 .. <len(n): track(tracked, n.sons[i]) of nkCheckedFieldExpr: track(tracked, n.sons[0]) if warnProveField in gNotes: checkFieldAccess(tracked.guards, n) @@ -601,6 +641,14 @@ proc track(tracked: PEffects, n: PNode) = if sfDiscriminant in x.sons[0].sym.flags: addDiscriminantFact(tracked.guards, x) setLen(tracked.guards, oldFacts) + of nkPragmaBlock: + let pragmaList = n.sons[0] + let oldLocked = tracked.locked.len + for i in 0 .. <pragmaList.len: + if whichPragma(pragmaList.sons[i]) == wLocks: + lockLocations(tracked, pragmaList.sons[i]) + track(tracked, n.lastSon) + setLen(tracked.locked, oldLocked) of nkTypeSection, nkProcDef, nkConverterDef, nkMethodDef, nkIteratorDef, nkMacroDef, nkTemplateDef: discard @@ -648,10 +696,6 @@ proc checkMethodEffects*(disp, branch: PSym) = if not isNil(tagsSpec): checkRaisesSpec(tagsSpec, actual.sons[tagEffects], "can have an unlisted effect: ", hints=off, subtypeRelation) - let usesSpec = effectSpec(p, wUses) - if not isNil(usesSpec): - checkRaisesSpec(usesSpec, actual.sons[usesEffects], - "may use an unlisted global variable: ", hints=off, symbolPredicate) if sfThread in disp.flags and notGcSafe(branch.typ): localError(branch.info, "base method is GC-safe, but '$1' is not" % branch.name.s) @@ -663,29 +707,25 @@ proc setEffectsForProcType*(t: PType, n: PNode) = let raisesSpec = effectSpec(n, wRaises) tagsSpec = effectSpec(n, wTags) - usesSpec = effectSpec(n, wUses) - if not isNil(raisesSpec) or not isNil(tagsSpec) or not isNil(usesSpec): + if not isNil(raisesSpec) or not isNil(tagsSpec): internalAssert effects.len == 0 newSeq(effects.sons, effectListLen) if not isNil(raisesSpec): effects.sons[exceptionEffects] = raisesSpec if not isNil(tagsSpec): effects.sons[tagEffects] = tagsSpec - if not isNil(usesSpec): - effects.sons[usesEffects] = usesSpec proc initEffects(effects: PNode; s: PSym; t: var TEffects) = newSeq(effects.sons, effectListLen) effects.sons[exceptionEffects] = newNodeI(nkArgList, s.info) effects.sons[tagEffects] = newNodeI(nkArgList, s.info) - effects.sons[usesEffects] = newNodeI(nkArgList, s.info) t.exc = effects.sons[exceptionEffects] t.tags = effects.sons[tagEffects] - t.uses = effects.sons[usesEffects] t.owner = s t.init = @[] t.guards = @[] + t.locked = @[] proc trackProc*(s: PSym, body: PNode) = var effects = s.typ.n.sons[0] @@ -717,16 +757,12 @@ proc trackProc*(s: PSym, body: PNode) = # after the check, use the formal spec: effects.sons[tagEffects] = tagsSpec - when trackGlobals: - let usesSpec = effectSpec(p, wUses) - if not isNil(usesSpec): - checkRaisesSpec(usesSpec, t.uses, - "uses an unlisted global variable: ", hints=on, symbolPredicate) - effects.sons[usesEffects] = usesSpec if optThreadAnalysis in gGlobalOptions: if sfThread in s.flags and t.gcUnsafe: - #localError(s.info, warnGcUnsafe2, s.name.s) - localError(s.info, "'$1' is not GC-safe" % s.name.s) + if optThreads in gGlobalOptions: + localError(s.info, "'$1' is not GC-safe" % s.name.s) + else: + localError(s.info, warnGcUnsafe2, s.name.s) if not t.gcUnsafe: s.typ.flags.incl tfGcSafe proc trackTopLevelStmt*(module: PSym; n: PNode) = @@ -736,5 +772,5 @@ proc trackTopLevelStmt*(module: PSym; n: PNode) = var effects = newNode(nkEffectList, n.info) var t: TEffects initEffects(effects, module, t) - + t.isToplevel = true track(t, n) |