diff options
Diffstat (limited to 'compiler/lambdalifting.nim')
| -rw-r--r-- | compiler/lambdalifting.nim | 61 |
1 files changed, 36 insertions, 25 deletions
diff --git a/compiler/lambdalifting.nim b/compiler/lambdalifting.nim index c32a1c614..54cdfc5bc 100644 --- a/compiler/lambdalifting.nim +++ b/compiler/lambdalifting.nim @@ -145,11 +145,13 @@ proc createStateField(g: ModuleGraph; iter: PSym; idgen: IdGenerator): PSym = 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: @@ -172,26 +174,22 @@ 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 - else: - result = nil - proc interestingVar(s: PSym): bool {.inline.} = result = s.kind in {skVar, skLet, skTemp, skForVar, skParam, skResult} and sfGlobal notin s.flags and @@ -231,13 +229,16 @@ 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 +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 + 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: @@ -255,11 +256,11 @@ proc genCreateEnv(env: PNode): PNode = 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: @@ -281,6 +282,7 @@ proc liftIterSym*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: PSym): PN 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}) let field = addField(obj, s, g.cache, idgen) @@ -298,8 +300,8 @@ proc markAsClosure(g: ModuleGraph; owner: PSym; n: PNode) = 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:nimNoLentIterators' helps in some cases." & - " Consider using a <ref $2> which can be captured.") % - [s.name.s, typeToString(s.typ), g.config$s.info]) + " 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]) @@ -336,9 +338,13 @@ proc getEnvTypeForOwner(c: var DetectionPass; owner: PSym; info: TLineInfo): PType = result = c.ownerToType.getOrDefault(owner.id) if result.isNil: - result = newType(tyRef, 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 = @@ -454,7 +460,7 @@ proc detectCapturedVars(n: PNode; owner: PSym; c: var DetectionPass) = if owner.isIterator: c.somethingToDo = true addClosureParam(c, owner, n.info) - if interestingIterVar(s): + 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}) @@ -768,7 +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) @@ -880,12 +886,16 @@ proc liftLambdas*(g: ModuleGraph; fn: PSym, body: PNode; tooEarly: var bool; 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 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) @@ -940,6 +950,7 @@ proc liftForLoop*(g: ModuleGraph; body: PNode; idgen: IdGenerator; owner: PSym): break ... """ + if liftingHarmful(g.config, owner): return body if not (body.kind == nkForStmt and body[^2].kind in nkCallKinds): localError(g.config, body.info, "ignored invalid for loop") return body |