diff options
Diffstat (limited to 'compiler/lambdalifting.nim')
| -rw-r--r-- | compiler/lambdalifting.nim | 217 |
1 files changed, 124 insertions, 93 deletions
diff --git a/compiler/lambdalifting.nim b/compiler/lambdalifting.nim index 6f43649a1..54cdfc5bc 100644 --- a/compiler/lambdalifting.nim +++ b/compiler/lambdalifting.nim @@ -10,9 +10,14 @@ # This file implements lambda lifting for the transformator. import - intsets, strutils, options, ast, astalgo, msgs, - idents, renderer, types, magicsys, lowerings, tables, modulegraphs, lineinfos, - transf, liftdestructors + options, ast, astalgo, msgs, + idents, renderer, types, magicsys, lowerings, modulegraphs, lineinfos, + transf, liftdestructors, typeallowed + +import std/[strutils, tables, intsets] + +when defined(nimPreviewSlimSystem): + import std/assertions discard """ The basic approach is that captured vars need to be put on the heap and @@ -130,29 +135,31 @@ proc createClosureIterStateType*(g: ModuleGraph; iter: PSym; idgen: IdGenerator) var n = newNodeI(nkRange, iter.info) n.add newIntNode(nkIntLit, -1) n.add newIntNode(nkIntLit, 0) - result = newType(tyRange, nextTypeId(idgen), iter) + result = newType(tyRange, idgen, iter) result.n = n var intType = nilOrSysInt(g) - if intType.isNil: intType = newType(tyInt, nextTypeId(idgen), iter) + if intType.isNil: intType = newType(tyInt, idgen, iter) rawAddSon(result, intType) proc createStateField(g: ModuleGraph; iter: PSym; idgen: IdGenerator): PSym = - result = newSym(skField, getIdent(g.cache, ":state"), nextSymId(idgen), iter, iter.info) + result = newSym(skField, getIdent(g.cache, ":state"), idgen, iter, iter.info) result.typ = createClosureIterStateType(g, iter, idgen) +template isIterator*(owner: PSym): bool = + owner.kind == skIterator and owner.typ.callConv == ccClosure + proc createEnvObj(g: ModuleGraph; idgen: IdGenerator; owner: PSym; info: TLineInfo): PType = - # YYY meh, just add the state field for every closure for now, it's too - # hard to figure out if it comes from a closure iterator: result = createObj(g, idgen, owner, info, final=false) - rawAddField(result, createStateField(g, owner, idgen)) + if owner.isIterator or not isDefined(g.config, "nimOptIters"): + rawAddField(result, createStateField(g, owner, idgen)) proc getClosureIterResult*(g: ModuleGraph; iter: PSym; idgen: IdGenerator): PSym = if resultPos < iter.ast.len: result = iter.ast[resultPos].sym else: # XXX a bit hacky: - result = newSym(skResult, getIdent(g.cache, ":result"), nextSymId(idgen), iter, iter.info, {}) - result.typ = iter.typ[0] + result = newSym(skResult, getIdent(g.cache, ":result"), idgen, iter, iter.info, {}) + result.typ = iter.typ.returnType incl(result.flags, sfUsed) iter.ast.add newSymNode(result) @@ -167,37 +174,35 @@ proc addHiddenParam(routine: PSym, param: PSym) = assert sfFromGeneric in param.flags #echo "produced environment: ", param.id, " for ", routine.id -proc getHiddenParam(g: ModuleGraph; routine: PSym): PSym = +proc getEnvParam*(routine: PSym): PSym = let params = routine.ast[paramsPos] let hidden = lastSon(params) if hidden.kind == nkSym and hidden.sym.kind == skParam and hidden.sym.name.s == paramName: result = hidden.sym assert sfFromGeneric in result.flags else: + result = nil + +proc getHiddenParam(g: ModuleGraph; routine: PSym): PSym = + result = getEnvParam(routine) + if result.isNil: # writeStackTrace() localError(g.config, routine.info, "internal error: could not find env param for " & routine.name.s) result = routine -proc getEnvParam*(routine: PSym): PSym = - let params = routine.ast[paramsPos] - let hidden = lastSon(params) - if hidden.kind == nkSym and hidden.sym.name.s == paramName: - result = hidden.sym - assert sfFromGeneric in result.flags - proc interestingVar(s: PSym): bool {.inline.} = result = s.kind in {skVar, skLet, skTemp, skForVar, skParam, skResult} and sfGlobal notin s.flags and s.typ.kind notin {tyStatic, tyTypeDesc} proc illegalCapture(s: PSym): bool {.inline.} = - result = skipTypes(s.typ, abstractInst).kind in - {tyVar, tyOpenArray, tyVarargs, tyLent} or - s.kind == skResult + result = classifyViewType(s.typ) != noView or s.kind == skResult proc isInnerProc(s: PSym): bool = if s.kind in {skProc, skFunc, skMethod, skConverter, skIterator} and s.magic == mNone: result = s.skipGenericOwner.kind in routineKinds + else: + result = false proc newAsgnStmt(le, ri: PNode, info: TLineInfo): PNode = # Bugfix: unfortunately we cannot use 'nkFastAsgn' here as that would @@ -224,34 +229,38 @@ proc makeClosure*(g: ModuleGraph; idgen: IdGenerator; prc: PSym; env: PNode; inf prc.flags.incl sfInjectDestructors proc interestingIterVar(s: PSym): bool {.inline.} = + # unused with -d:nimOptIters # XXX optimization: Only lift the variable if it lives across # yield/return boundaries! This can potentially speed up # closure iterators quite a bit. result = s.kind in {skResult, skVar, skLet, skTemp, skForVar} and sfGlobal notin s.flags -template isIterator*(owner: PSym): bool = - owner.kind == skIterator and owner.typ.callConv == ccClosure - -proc liftingHarmful(conf: ConfigRef; owner: PSym): bool {.inline.} = +template liftingHarmful(conf: ConfigRef; owner: PSym): bool = ## lambda lifting can be harmful for JS-like code generators. let isCompileTime = sfCompileTime in owner.flags or owner.kind == skMacro - result = conf.backend == backendJs and not isCompileTime + jsNoLambdaLifting in conf.legacyFeatures and conf.backend == backendJs and not isCompileTime proc createTypeBoundOpsLL(g: ModuleGraph; refType: PType; info: TLineInfo; idgen: IdGenerator; owner: PSym) = if owner.kind != skMacro: - createTypeBoundOps(g, nil, refType.lastSon, info, idgen) + createTypeBoundOps(g, nil, refType.elementType, info, idgen) createTypeBoundOps(g, nil, refType, info, idgen) if tfHasAsgn in refType.flags or optSeqDestructors in g.config.globalOptions: owner.flags.incl sfInjectDestructors +proc genCreateEnv(env: PNode): PNode = + var c = newNodeIT(nkObjConstr, env.info, env.typ) + c.add newNodeIT(nkType, env.info, env.typ) + let e = copyTree(env) + e.flags.incl nfFirstWrite + result = newAsgnStmt(e, c) + proc liftIterSym*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: PSym): PNode = # transforms (iter) to (let env = newClosure[iter](); (iter, env)) if liftingHarmful(g.config, owner): return n let iter = n.sym assert iter.isIterator - result = newNodeIT(nkStmtListExpr, n.info, n.typ) - + result = newNodeIT(nkStmtListExpr, n.info, iter.typ) let hp = getHiddenParam(g, iter) var env: PNode if owner.isIterator: @@ -259,7 +268,7 @@ proc liftIterSym*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: PSym): PN addUniqueField(it.typ.skipTypes({tyOwned})[0], hp, g.cache, idgen) env = indirectAccess(newSymNode(it), hp, hp.info) else: - let e = newSym(skLet, iter.name, nextSymId(idgen), owner, n.info) + let e = newSym(skLet, iter.name, idgen, owner, n.info) e.typ = hp.typ e.flags = hp.flags env = newSymNode(e) @@ -267,54 +276,53 @@ proc liftIterSym*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: PSym): PN addVar(v, env) result.add(v) # add 'new' statement: - result.add newCall(getSysSym(g, n.info, "internalNew"), env) + #result.add newCall(getSysSym(g, n.info, "internalNew"), env) + result.add genCreateEnv(env) createTypeBoundOpsLL(g, env.typ, n.info, idgen, owner) result.add makeClosure(g, idgen, iter, env, n.info) proc freshVarForClosureIter*(g: ModuleGraph; s: PSym; idgen: IdGenerator; owner: PSym): PNode = + # unused with -d:nimOptIters let envParam = getHiddenParam(g, owner) let obj = envParam.typ.skipTypes({tyOwned, tyRef, tyPtr}) - addField(obj, s, g.cache, idgen) + let field = addField(obj, s, g.cache, idgen) var access = newSymNode(envParam) assert obj.kind == tyObject - let field = getFieldFromObj(obj, s) - if field != nil: - result = rawIndirectAccess(access, field, s.info) - else: - localError(g.config, s.info, "internal error: cannot generate fresh variable") - result = access + result = rawIndirectAccess(access, field, s.info) # ------------------ new stuff ------------------------------------------- proc markAsClosure(g: ModuleGraph; owner: PSym; n: PNode) = let s = n.sym + let isEnv = s.name.id == getIdent(g.cache, ":env").id if illegalCapture(s): localError(g.config, n.info, ("'$1' is of type <$2> which cannot be captured as it would violate memory" & - " safety, declared here: $3; using '-d:nimWorkaround14447' helps in some cases") % - [s.name.s, typeToString(s.typ), g.config$s.info]) - elif not (owner.typ.callConv == ccClosure or owner.typ.callConv == ccNimCall and tfExplicitCallConv notin owner.typ.flags): + " safety, declared here: $3; using '-d:nimNoLentIterators' helps in some cases." & + " Consider using a <ref T> which can be captured.") % + [s.name.s, typeToString(s.typ.skipTypes({tyVar})), g.config$s.info]) + elif not (owner.typ.isClosure or owner.isNimcall and not owner.isExplicitCallConv or isEnv): localError(g.config, n.info, "illegal capture '$1' because '$2' has the calling convention: <$3>" % [s.name.s, owner.name.s, $owner.typ.callConv]) incl(owner.typ.flags, tfCapturesEnv) - owner.typ.callConv = ccClosure + if not isEnv: + owner.typ.callConv = ccClosure type DetectionPass = object processed, capturedVars: IntSet ownerToType: Table[int, PType] somethingToDo: bool + inTypeOf: bool graph: ModuleGraph idgen: IdGenerator proc initDetectionPass(g: ModuleGraph; fn: PSym; idgen: IdGenerator): DetectionPass = - result.processed = initIntSet() - result.capturedVars = initIntSet() - result.ownerToType = initTable[int, PType]() - result.processed.incl(fn.id) - result.graph = g - result.idgen = idgen + result = DetectionPass(processed: toIntSet([fn.id]), + capturedVars: initIntSet(), ownerToType: initTable[int, PType](), + graph: g, idgen: idgen + ) discard """ proc outer = @@ -330,15 +338,19 @@ proc getEnvTypeForOwner(c: var DetectionPass; owner: PSym; info: TLineInfo): PType = result = c.ownerToType.getOrDefault(owner.id) if result.isNil: - result = newType(tyRef, nextTypeId(c.idgen), owner) - let obj = createEnvObj(c.graph, c.idgen, owner, info) - rawAddSon(result, obj) + let env = getEnvParam(owner) + if env.isNil or not owner.isIterator or not isDefined(c.graph.config, "nimOptIters"): + result = newType(tyRef, c.idgen, owner) + let obj = createEnvObj(c.graph, c.idgen, owner, info) + rawAddSon(result, obj) + else: + result = env.typ c.ownerToType[owner.id] = result proc asOwnedRef(c: var DetectionPass; t: PType): PType = if optOwnedRefs in c.graph.config.globalOptions: assert t.kind == tyRef - result = newType(tyOwned, nextTypeId(c.idgen), t.owner) + result = newType(tyOwned, c.idgen, t.owner) result.flags.incl tfHasOwned result.rawAddSon t else: @@ -347,7 +359,7 @@ proc asOwnedRef(c: var DetectionPass; t: PType): PType = proc getEnvTypeForOwnerUp(c: var DetectionPass; owner: PSym; info: TLineInfo): PType = var r = c.getEnvTypeForOwner(owner, info) - result = newType(tyPtr, nextTypeId(c.idgen), owner) + result = newType(tyPtr, c.idgen, owner) rawAddSon(result, r.skipTypes({tyOwned, tyRef, tyPtr})) proc createUpField(c: var DetectionPass; dest, dep: PSym; info: TLineInfo) = @@ -375,7 +387,7 @@ proc createUpField(c: var DetectionPass; dest, dep: PSym; info: TLineInfo) = if c.graph.config.selectedGC == gcDestructors and sfCursor notin upField.flags: localError(c.graph.config, dep.info, "internal error: up reference is not a .cursor") else: - let result = newSym(skField, upIdent, nextSymId(c.idgen), obj.owner, obj.owner.info) + let result = newSym(skField, upIdent, c.idgen, obj.owner, obj.owner.info) result.typ = fieldType when false: if c.graph.config.selectedGC == gcDestructors: @@ -408,12 +420,15 @@ Consider: """ +proc isTypeOf(n: PNode): bool = + n.kind == nkSym and n.sym.magic in {mTypeOf, mType} + proc addClosureParam(c: var DetectionPass; fn: PSym; info: TLineInfo) = var cp = getEnvParam(fn) let owner = if fn.kind == skIterator: fn else: fn.skipGenericOwner let t = c.getEnvTypeForOwner(owner, info) if cp == nil: - cp = newSym(skParam, getIdent(c.graph.cache, paramName), nextSymId(c.idgen), fn, fn.info) + cp = newSym(skParam, getIdent(c.graph.cache, paramName), c.idgen, fn, fn.info) incl(cp.flags, sfFromGeneric) cp.typ = t addHiddenParam(fn, cp) @@ -436,24 +451,28 @@ proc detectCapturedVars(n: PNode; owner: PSym; c: var DetectionPass) = if innerProc: if s.isIterator: c.somethingToDo = true if not c.processed.containsOrIncl(s.id): - let body = transformBody(c.graph, c.idgen, s, cache = true) + let body = transformBody(c.graph, c.idgen, s, {useCache}) detectCapturedVars(body, s, c) let ow = s.skipGenericOwner + let innerClosure = innerProc and s.typ.callConv == ccClosure and not s.isIterator + let interested = interestingVar(s) if ow == owner: if owner.isIterator: c.somethingToDo = true addClosureParam(c, owner, n.info) - if interestingIterVar(s): - if not c.capturedVars.containsOrIncl(s.id): + if not isDefined(c.graph.config, "nimOptIters") and interestingIterVar(s): + if not c.capturedVars.contains(s.id): + if not c.inTypeOf: c.capturedVars.incl(s.id) let obj = getHiddenParam(c.graph, owner).typ.skipTypes({tyOwned, tyRef, tyPtr}) #let obj = c.getEnvTypeForOwner(s.owner).skipTypes({tyOwned, tyRef, tyPtr}) if s.name.id == getIdent(c.graph.cache, ":state").id: + obj.n[0].sym.flags.incl sfNoInit obj.n[0].sym.itemId = ItemId(module: s.itemId.module, item: -s.itemId.item) else: - addField(obj, s, c.graph.cache, c.idgen) + discard addField(obj, s, c.graph.cache, c.idgen) # direct or indirect dependency: - elif (innerProc and s.typ.callConv == ccClosure) or interestingVar(s): + elif innerClosure or interested: discard """ proc outer() = var x: int @@ -470,10 +489,12 @@ proc detectCapturedVars(n: PNode; owner: PSym; c: var DetectionPass) = addClosureParam(c, owner, n.info) #echo "capturing ", n.info # variable 's' is actually captured: - if interestingVar(s) and not c.capturedVars.containsOrIncl(s.id): - let obj = c.getEnvTypeForOwner(ow, n.info).skipTypes({tyOwned, tyRef, tyPtr}) - #getHiddenParam(owner).typ.skipTypes({tyOwned, tyRef, tyPtr}) - addField(obj, s, c.graph.cache, c.idgen) + if interestingVar(s): + if not c.capturedVars.contains(s.id): + if not c.inTypeOf: c.capturedVars.incl(s.id) + let obj = c.getEnvTypeForOwner(ow, n.info).skipTypes({tyOwned, tyRef, tyPtr}) + #getHiddenParam(owner).typ.skipTypes({tyOwned, tyRef, tyPtr}) + discard addField(obj, s, c.graph.cache, c.idgen) # create required upFields: var w = owner.skipGenericOwner if isInnerProc(w) or owner.isIterator: @@ -505,9 +526,14 @@ proc detectCapturedVars(n: PNode; owner: PSym; c: var DetectionPass) = detectCapturedVars(n[namePos], owner, c) of nkReturnStmt: detectCapturedVars(n[0], owner, c) + of nkIdentDefs: + detectCapturedVars(n[^1], owner, c) else: + if n.isCallExpr and n[0].isTypeOf: + c.inTypeOf = true for i in 0..<n.len: detectCapturedVars(n[i], owner, c) + c.inTypeOf = false type LiftingPass = object @@ -517,9 +543,8 @@ type unownedEnvVars: Table[int, PNode] # only required for --newruntime proc initLiftingPass(fn: PSym): LiftingPass = - result.processed = initIntSet() - result.processed.incl(fn.id) - result.envVars = initTable[int, PNode]() + result = LiftingPass(processed: toIntSet([fn.id]), + envVars: initTable[int, PNode]()) proc accessViaEnvParam(g: ModuleGraph; n: PNode; owner: PSym): PNode = let s = n.sym @@ -527,8 +552,8 @@ proc accessViaEnvParam(g: ModuleGraph; n: PNode; owner: PSym): PNode = let envParam = getHiddenParam(g, owner) if not envParam.isNil: var access = newSymNode(envParam) + var obj = access.typ.elementType while true: - let obj = access.typ[0] assert obj.kind == tyObject let field = getFieldFromObj(obj, s) if field != nil: @@ -536,18 +561,19 @@ proc accessViaEnvParam(g: ModuleGraph; n: PNode; owner: PSym): PNode = let upField = lookupInRecord(obj.n, getIdent(g.cache, upName)) if upField == nil: break access = rawIndirectAccess(access, upField, n.info) + obj = access.typ.baseClass localError(g.config, n.info, "internal error: environment misses: " & s.name.s) result = n proc newEnvVar(cache: IdentCache; owner: PSym; typ: PType; info: TLineInfo; idgen: IdGenerator): PNode = - var v = newSym(skVar, getIdent(cache, envName), nextSymId(idgen), owner, info) + var v = newSym(skVar, getIdent(cache, envName), idgen, owner, info) v.flags = {sfShadowed, sfGeneratedOp} v.typ = typ result = newSymNode(v) when false: if owner.kind == skIterator and owner.typ.callConv == ccClosure: let it = getHiddenParam(owner) - addUniqueField(it.typ[0], v) + addUniqueField(it.typ.elementType, v) result = indirectAccess(newSymNode(it), v, v.info) else: result = newSymNode(v) @@ -564,7 +590,7 @@ proc setupEnvVar(owner: PSym; d: var DetectionPass; result = newEnvVar(d.graph.cache, owner, asOwnedRef(d, envVarType), info, d.idgen) c.envVars[owner.id] = result if optOwnedRefs in d.graph.config.globalOptions: - var v = newSym(skVar, getIdent(d.graph.cache, envName & "Alt"), nextSymId d.idgen, owner, info) + var v = newSym(skVar, getIdent(d.graph.cache, envName & "Alt"), d.idgen, owner, info) v.flags = {sfShadowed, sfGeneratedOp} v.typ = envVarType c.unownedEnvVars[owner.id] = newSymNode(v) @@ -599,7 +625,7 @@ proc rawClosureCreation(owner: PSym; addVar(v, unowned) # add 'new' statement: - result.add(newCall(getSysSym(d.graph, env.info, "internalNew"), env)) + result.add genCreateEnv(env) if optOwnedRefs in d.graph.config.globalOptions: let unowned = c.unownedEnvVars[owner.id] assert unowned != nil @@ -648,7 +674,7 @@ proc closureCreationForIter(iter: PNode; d: var DetectionPass; c: var LiftingPass): PNode = result = newNodeIT(nkStmtListExpr, iter.info, iter.sym.typ) let owner = iter.sym.skipGenericOwner - var v = newSym(skVar, getIdent(d.graph.cache, envName), nextSymId(d.idgen), owner, iter.info) + var v = newSym(skVar, getIdent(d.graph.cache, envName), d.idgen, owner, iter.info) incl(v.flags, sfShadowed) v.typ = asOwnedRef(d, getHiddenParam(d.graph, iter.sym).typ) var vnode: PNode @@ -661,7 +687,7 @@ proc closureCreationForIter(iter: PNode; var vs = newNodeI(nkVarSection, iter.info) addVar(vs, vnode) result.add(vs) - result.add(newCall(getSysSym(d.graph, iter.info, "internalNew"), vnode)) + result.add genCreateEnv(vnode) createTypeBoundOpsLL(d.graph, vnode.typ, iter.info, d.idgen, owner) let upField = lookupInRecord(v.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(d.graph.cache, upName)) @@ -706,6 +732,7 @@ proc symToClosure(n: PNode; owner: PSym; d: var DetectionPass; # direct dependency, so use the outer's env variable: result = makeClosure(d.graph, d.idgen, s, setupEnvVar(owner, d, c, n.info), n.info) else: + result = nil let available = getHiddenParam(d.graph, owner) let wanted = getHiddenParam(d.graph, s).typ # ugh: call through some other inner proc; @@ -732,7 +759,7 @@ proc liftCapturedVars(n: PNode; owner: PSym; d: var DetectionPass; # echo renderTree(s.getBody, {renderIds}) let oldInContainer = c.inContainer c.inContainer = 0 - var body = transformBody(d.graph, d.idgen, s, cache = false) + var body = transformBody(d.graph, d.idgen, s, {}) body = liftCapturedVars(body, s, d, c) if c.envVars.getOrDefault(s.id).isNil: s.transformedBody = body @@ -747,7 +774,7 @@ proc liftCapturedVars(n: PNode; owner: PSym; d: var DetectionPass; elif s.id in d.capturedVars: if s.owner != owner: result = accessViaEnvParam(d.graph, n, owner) - elif owner.isIterator and interestingIterVar(s): + elif owner.isIterator and not isDefined(d.graph.config, "nimOptIters") and interestingIterVar(s): result = accessViaEnvParam(d.graph, n, owner) else: result = accessViaEnvVar(n, owner, d, c) @@ -777,7 +804,7 @@ proc liftCapturedVars(n: PNode; owner: PSym; d: var DetectionPass; n[1] = liftCapturedVars(n[1], owner, d, c) if n[1].kind == nkClosure: result = n[1] of nkReturnStmt: - if n[0].kind in {nkAsgn, nkFastAsgn}: + if n[0].kind in {nkAsgn, nkFastAsgn, nkSinkAsgn}: # we have a `result = result` expression produced by the closure # transform, let's not touch the LHS in order to make the lifting pass # correct when `result` is lifted @@ -787,6 +814,8 @@ proc liftCapturedVars(n: PNode; owner: PSym; d: var DetectionPass; of nkTypeOfExpr: result = n else: + if n.isCallExpr and n[0].isTypeOf: + return if owner.isIterator: if nfLL in n.flags: # special case 'when nimVm' due to bug #3636: @@ -854,20 +883,19 @@ proc liftIterToProc*(g: ModuleGraph; fn: PSym; body: PNode; ptrType: PType; fn.typ.callConv = oldCC proc liftLambdas*(g: ModuleGraph; fn: PSym, body: PNode; tooEarly: var bool; - idgen: IdGenerator): PNode = - # XXX backend == backendJs does not suffice! The compiletime stuff needs - # the transformation even when compiling to JS ... - - # However we can do lifting for the stuff which is *only* compiletime. + idgen: IdGenerator; flags: TransformFlags): PNode = let isCompileTime = sfCompileTime in fn.flags or fn.kind == skMacro - if body.kind == nkEmpty or ( + if body.kind == nkEmpty or (jsNoLambdaLifting in g.config.legacyFeatures and g.config.backend == backendJs and not isCompileTime) or - fn.skipGenericOwner.kind != skModule: + (fn.skipGenericOwner.kind != skModule and force notin flags): # ignore forward declaration: result = body tooEarly = true + if fn.isIterator and isDefined(g.config, "nimOptIters"): + var d = initDetectionPass(g, fn, idgen) + addClosureParam(d, fn, body.info) else: var d = initDetectionPass(g, fn, idgen) detectCapturedVars(body, fn, d) @@ -931,14 +959,14 @@ proc liftForLoop*(g: ModuleGraph; body: PNode; idgen: IdGenerator; owner: PSym): result = newNodeI(nkStmtList, body.info) # static binding? - var env: PSym + var env: PSym = nil let op = call[0] if op.kind == nkSym and op.sym.isIterator: # createClosure() let iter = op.sym let hp = getHiddenParam(g, iter) - env = newSym(skLet, iter.name, nextSymId(idgen), owner, body.info) + env = newSym(skLet, iter.name, idgen, owner, body.info) env.typ = hp.typ env.flags = hp.flags @@ -946,7 +974,7 @@ proc liftForLoop*(g: ModuleGraph; body: PNode; idgen: IdGenerator; owner: PSym): addVar(v, newSymNode(env)) result.add(v) # add 'new' statement: - result.add(newCall(getSysSym(g, env.info, "internalNew"), env.newSymNode)) + result.add genCreateEnv(env.newSymNode) createTypeBoundOpsLL(g, env.typ, body.info, idgen, owner) elif op.kind == nkStmtListExpr: @@ -966,12 +994,15 @@ proc liftForLoop*(g: ModuleGraph; body: PNode; idgen: IdGenerator; owner: PSym): # gather vars in a tuple: var v2 = newNodeI(nkLetSection, body.info) var vpart = newNodeI(if body.len == 3: nkIdentDefs else: nkVarTuple, body.info) - for i in 0..<body.len-2: - if body[i].kind == nkSym: - body[i].sym.transitionToLet() - vpart.add body[i] + if body.len == 3 and body[0].kind == nkVarTuple: + vpart = body[0] # fixes for (i,j) in walk() # bug #15924 + else: + for i in 0..<body.len-2: + if body[i].kind == nkSym: + body[i].sym.transitionToLet() + vpart.add body[i] - vpart.add newNodeI(nkEmpty, body.info) # no explicit type + vpart.add newNodeI(nkEmpty, body.info) # no explicit type if not env.isNil: call[0] = makeClosure(g, idgen, call[0].sym, env.newSymNode, body.info) vpart.add call |