| //===- SetTheory.cpp - Generate ordered sets from DAG expressions ---------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the SetTheory class that computes ordered sets of |
| // Records from DAG expressions. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "SetTheory.h" |
| #include "llvm/TableGen/Error.h" |
| #include "llvm/TableGen/Record.h" |
| #include "llvm/Support/Format.h" |
| |
| using namespace llvm; |
| |
| // Define the standard operators. |
| namespace { |
| |
| typedef SetTheory::RecSet RecSet; |
| typedef SetTheory::RecVec RecVec; |
| |
| // (add a, b, ...) Evaluate and union all arguments. |
| struct AddOp : public SetTheory::Operator { |
| void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts) { |
| ST.evaluate(Expr->arg_begin(), Expr->arg_end(), Elts); |
| } |
| }; |
| |
| // (sub Add, Sub, ...) Set difference. |
| struct SubOp : public SetTheory::Operator { |
| void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts) { |
| if (Expr->arg_size() < 2) |
| throw "Set difference needs at least two arguments: " + |
| Expr->getAsString(); |
| RecSet Add, Sub; |
| ST.evaluate(*Expr->arg_begin(), Add); |
| ST.evaluate(Expr->arg_begin() + 1, Expr->arg_end(), Sub); |
| for (RecSet::iterator I = Add.begin(), E = Add.end(); I != E; ++I) |
| if (!Sub.count(*I)) |
| Elts.insert(*I); |
| } |
| }; |
| |
| // (and S1, S2) Set intersection. |
| struct AndOp : public SetTheory::Operator { |
| void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts) { |
| if (Expr->arg_size() != 2) |
| throw "Set intersection requires two arguments: " + Expr->getAsString(); |
| RecSet S1, S2; |
| ST.evaluate(Expr->arg_begin()[0], S1); |
| ST.evaluate(Expr->arg_begin()[1], S2); |
| for (RecSet::iterator I = S1.begin(), E = S1.end(); I != E; ++I) |
| if (S2.count(*I)) |
| Elts.insert(*I); |
| } |
| }; |
| |
| // SetIntBinOp - Abstract base class for (Op S, N) operators. |
| struct SetIntBinOp : public SetTheory::Operator { |
| virtual void apply2(SetTheory &ST, DagInit *Expr, |
| RecSet &Set, int64_t N, |
| RecSet &Elts) =0; |
| |
| void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts) { |
| if (Expr->arg_size() != 2) |
| throw "Operator requires (Op Set, Int) arguments: " + Expr->getAsString(); |
| RecSet Set; |
| ST.evaluate(Expr->arg_begin()[0], Set); |
| IntInit *II = dynamic_cast<IntInit*>(Expr->arg_begin()[1]); |
| if (!II) |
| throw "Second argument must be an integer: " + Expr->getAsString(); |
| apply2(ST, Expr, Set, II->getValue(), Elts); |
| } |
| }; |
| |
| // (shl S, N) Shift left, remove the first N elements. |
| struct ShlOp : public SetIntBinOp { |
| void apply2(SetTheory &ST, DagInit *Expr, |
| RecSet &Set, int64_t N, |
| RecSet &Elts) { |
| if (N < 0) |
| throw "Positive shift required: " + Expr->getAsString(); |
| if (unsigned(N) < Set.size()) |
| Elts.insert(Set.begin() + N, Set.end()); |
| } |
| }; |
| |
| // (trunc S, N) Truncate after the first N elements. |
| struct TruncOp : public SetIntBinOp { |
| void apply2(SetTheory &ST, DagInit *Expr, |
| RecSet &Set, int64_t N, |
| RecSet &Elts) { |
| if (N < 0) |
| throw "Positive length required: " + Expr->getAsString(); |
| if (unsigned(N) > Set.size()) |
| N = Set.size(); |
| Elts.insert(Set.begin(), Set.begin() + N); |
| } |
| }; |
| |
| // Left/right rotation. |
| struct RotOp : public SetIntBinOp { |
| const bool Reverse; |
| |
| RotOp(bool Rev) : Reverse(Rev) {} |
| |
| void apply2(SetTheory &ST, DagInit *Expr, |
| RecSet &Set, int64_t N, |
| RecSet &Elts) { |
| if (Reverse) |
| N = -N; |
| // N > 0 -> rotate left, N < 0 -> rotate right. |
| if (Set.empty()) |
| return; |
| if (N < 0) |
| N = Set.size() - (-N % Set.size()); |
| else |
| N %= Set.size(); |
| Elts.insert(Set.begin() + N, Set.end()); |
| Elts.insert(Set.begin(), Set.begin() + N); |
| } |
| }; |
| |
| // (decimate S, N) Pick every N'th element of S. |
| struct DecimateOp : public SetIntBinOp { |
| void apply2(SetTheory &ST, DagInit *Expr, |
| RecSet &Set, int64_t N, |
| RecSet &Elts) { |
| if (N <= 0) |
| throw "Positive stride required: " + Expr->getAsString(); |
| for (unsigned I = 0; I < Set.size(); I += N) |
| Elts.insert(Set[I]); |
| } |
| }; |
| |
| // (sequence "Format", From, To) Generate a sequence of records by name. |
| struct SequenceOp : public SetTheory::Operator { |
| void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts) { |
| if (Expr->arg_size() != 3) |
| throw "Bad args to (sequence \"Format\", From, To): " + |
| Expr->getAsString(); |
| std::string Format; |
| if (StringInit *SI = dynamic_cast<StringInit*>(Expr->arg_begin()[0])) |
| Format = SI->getValue(); |
| else |
| throw "Format must be a string: " + Expr->getAsString(); |
| |
| int64_t From, To; |
| if (IntInit *II = dynamic_cast<IntInit*>(Expr->arg_begin()[1])) |
| From = II->getValue(); |
| else |
| throw "From must be an integer: " + Expr->getAsString(); |
| if (From < 0 || From >= (1 << 30)) |
| throw "From out of range"; |
| |
| if (IntInit *II = dynamic_cast<IntInit*>(Expr->arg_begin()[2])) |
| To = II->getValue(); |
| else |
| throw "From must be an integer: " + Expr->getAsString(); |
| if (To < 0 || To >= (1 << 30)) |
| throw "To out of range"; |
| |
| RecordKeeper &Records = |
| dynamic_cast<DefInit&>(*Expr->getOperator()).getDef()->getRecords(); |
| |
| int Step = From <= To ? 1 : -1; |
| for (To += Step; From != To; From += Step) { |
| std::string Name; |
| raw_string_ostream OS(Name); |
| OS << format(Format.c_str(), unsigned(From)); |
| Record *Rec = Records.getDef(OS.str()); |
| if (!Rec) |
| throw "No def named '" + Name + "': " + Expr->getAsString(); |
| // Try to reevaluate Rec in case it is a set. |
| if (const RecVec *Result = ST.expand(Rec)) |
| Elts.insert(Result->begin(), Result->end()); |
| else |
| Elts.insert(Rec); |
| } |
| } |
| }; |
| |
| // Expand a Def into a set by evaluating one of its fields. |
| struct FieldExpander : public SetTheory::Expander { |
| StringRef FieldName; |
| |
| FieldExpander(StringRef fn) : FieldName(fn) {} |
| |
| void expand(SetTheory &ST, Record *Def, RecSet &Elts) { |
| ST.evaluate(Def->getValueInit(FieldName), Elts); |
| } |
| }; |
| } // end anonymous namespace |
| |
| void SetTheory::Operator::anchor() { } |
| |
| void SetTheory::Expander::anchor() { } |
| |
| SetTheory::SetTheory() { |
| addOperator("add", new AddOp); |
| addOperator("sub", new SubOp); |
| addOperator("and", new AndOp); |
| addOperator("shl", new ShlOp); |
| addOperator("trunc", new TruncOp); |
| addOperator("rotl", new RotOp(false)); |
| addOperator("rotr", new RotOp(true)); |
| addOperator("decimate", new DecimateOp); |
| addOperator("sequence", new SequenceOp); |
| } |
| |
| void SetTheory::addOperator(StringRef Name, Operator *Op) { |
| Operators[Name] = Op; |
| } |
| |
| void SetTheory::addExpander(StringRef ClassName, Expander *E) { |
| Expanders[ClassName] = E; |
| } |
| |
| void SetTheory::addFieldExpander(StringRef ClassName, StringRef FieldName) { |
| addExpander(ClassName, new FieldExpander(FieldName)); |
| } |
| |
| void SetTheory::evaluate(Init *Expr, RecSet &Elts) { |
| // A def in a list can be a just an element, or it may expand. |
| if (DefInit *Def = dynamic_cast<DefInit*>(Expr)) { |
| if (const RecVec *Result = expand(Def->getDef())) |
| return Elts.insert(Result->begin(), Result->end()); |
| Elts.insert(Def->getDef()); |
| return; |
| } |
| |
| // Lists simply expand. |
| if (ListInit *LI = dynamic_cast<ListInit*>(Expr)) |
| return evaluate(LI->begin(), LI->end(), Elts); |
| |
| // Anything else must be a DAG. |
| DagInit *DagExpr = dynamic_cast<DagInit*>(Expr); |
| if (!DagExpr) |
| throw "Invalid set element: " + Expr->getAsString(); |
| DefInit *OpInit = dynamic_cast<DefInit*>(DagExpr->getOperator()); |
| if (!OpInit) |
| throw "Bad set expression: " + Expr->getAsString(); |
| Operator *Op = Operators.lookup(OpInit->getDef()->getName()); |
| if (!Op) |
| throw "Unknown set operator: " + Expr->getAsString(); |
| Op->apply(*this, DagExpr, Elts); |
| } |
| |
| const RecVec *SetTheory::expand(Record *Set) { |
| // Check existing entries for Set and return early. |
| ExpandMap::iterator I = Expansions.find(Set); |
| if (I != Expansions.end()) |
| return &I->second; |
| |
| // This is the first time we see Set. Find a suitable expander. |
| try { |
| const std::vector<Record*> &SC = Set->getSuperClasses(); |
| for (unsigned i = 0, e = SC.size(); i != e; ++i) |
| if (Expander *Exp = Expanders.lookup(SC[i]->getName())) { |
| // This breaks recursive definitions. |
| RecVec &EltVec = Expansions[Set]; |
| RecSet Elts; |
| Exp->expand(*this, Set, Elts); |
| EltVec.assign(Elts.begin(), Elts.end()); |
| return &EltVec; |
| } |
| } catch (const std::string &Error) { |
| throw TGError(Set->getLoc(), Error); |
| } |
| |
| // Set is not expandable. |
| return 0; |
| } |
| |