1 //===- SetTheory.cpp - Generate ordered sets from DAG expressions ---------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This file implements the SetTheory class that computes ordered sets of
10 // Records from DAG expressions.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/ADT/ArrayRef.h"
15 #include "llvm/ADT/SmallVector.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/ADT/StringRef.h"
18 #include "llvm/Support/Casting.h"
19 #include "llvm/Support/Format.h"
20 #include "llvm/Support/SMLoc.h"
21 #include "llvm/Support/raw_ostream.h"
22 #include "llvm/TableGen/Error.h"
23 #include "llvm/TableGen/Record.h"
24 #include "llvm/TableGen/SetTheory.h"
32 // Define the standard operators.
35 using RecSet = SetTheory::RecSet;
36 using RecVec = SetTheory::RecVec;
38 // (add a, b, ...) Evaluate and union all arguments.
39 struct AddOp : public SetTheory::Operator {
40 void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts,
41 ArrayRef<SMLoc> Loc) override {
42 ST.evaluate(Expr->arg_begin(), Expr->arg_end(), Elts, Loc);
46 // (sub Add, Sub, ...) Set difference.
47 struct SubOp : public SetTheory::Operator {
48 void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts,
49 ArrayRef<SMLoc> Loc) override {
50 if (Expr->arg_size() < 2)
51 PrintFatalError(Loc, "Set difference needs at least two arguments: " +
54 ST.evaluate(*Expr->arg_begin(), Add, Loc);
55 ST.evaluate(Expr->arg_begin() + 1, Expr->arg_end(), Sub, Loc);
56 for (RecSet::iterator I = Add.begin(), E = Add.end(); I != E; ++I)
62 // (and S1, S2) Set intersection.
63 struct AndOp : public SetTheory::Operator {
64 void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts,
65 ArrayRef<SMLoc> Loc) override {
66 if (Expr->arg_size() != 2)
67 PrintFatalError(Loc, "Set intersection requires two arguments: " +
70 ST.evaluate(Expr->arg_begin()[0], S1, Loc);
71 ST.evaluate(Expr->arg_begin()[1], S2, Loc);
72 for (RecSet::iterator I = S1.begin(), E = S1.end(); I != E; ++I)
78 // SetIntBinOp - Abstract base class for (Op S, N) operators.
79 struct SetIntBinOp : public SetTheory::Operator {
80 virtual void apply2(SetTheory &ST, DagInit *Expr, RecSet &Set, int64_t N,
81 RecSet &Elts, ArrayRef<SMLoc> Loc) = 0;
83 void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts,
84 ArrayRef<SMLoc> Loc) override {
85 if (Expr->arg_size() != 2)
86 PrintFatalError(Loc, "Operator requires (Op Set, Int) arguments: " +
89 ST.evaluate(Expr->arg_begin()[0], Set, Loc);
90 IntInit *II = dyn_cast<IntInit>(Expr->arg_begin()[1]);
92 PrintFatalError(Loc, "Second argument must be an integer: " +
94 apply2(ST, Expr, Set, II->getValue(), Elts, Loc);
98 // (shl S, N) Shift left, remove the first N elements.
99 struct ShlOp : public SetIntBinOp {
100 void apply2(SetTheory &ST, DagInit *Expr, RecSet &Set, int64_t N,
101 RecSet &Elts, ArrayRef<SMLoc> Loc) override {
103 PrintFatalError(Loc, "Positive shift required: " +
104 Expr->getAsString());
105 if (unsigned(N) < Set.size())
106 Elts.insert(Set.begin() + N, Set.end());
110 // (trunc S, N) Truncate after the first N elements.
111 struct TruncOp : public SetIntBinOp {
112 void apply2(SetTheory &ST, DagInit *Expr, RecSet &Set, int64_t N,
113 RecSet &Elts, ArrayRef<SMLoc> Loc) override {
115 PrintFatalError(Loc, "Positive length required: " +
116 Expr->getAsString());
117 if (unsigned(N) > Set.size())
119 Elts.insert(Set.begin(), Set.begin() + N);
123 // Left/right rotation.
124 struct RotOp : public SetIntBinOp {
127 RotOp(bool Rev) : Reverse(Rev) {}
129 void apply2(SetTheory &ST, DagInit *Expr, RecSet &Set, int64_t N,
130 RecSet &Elts, ArrayRef<SMLoc> Loc) override {
133 // N > 0 -> rotate left, N < 0 -> rotate right.
137 N = Set.size() - (-N % Set.size());
140 Elts.insert(Set.begin() + N, Set.end());
141 Elts.insert(Set.begin(), Set.begin() + N);
145 // (decimate S, N) Pick every N'th element of S.
146 struct DecimateOp : public SetIntBinOp {
147 void apply2(SetTheory &ST, DagInit *Expr, RecSet &Set, int64_t N,
148 RecSet &Elts, ArrayRef<SMLoc> Loc) override {
150 PrintFatalError(Loc, "Positive stride required: " +
151 Expr->getAsString());
152 for (unsigned I = 0; I < Set.size(); I += N)
157 // (interleave S1, S2, ...) Interleave elements of the arguments.
158 struct InterleaveOp : public SetTheory::Operator {
159 void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts,
160 ArrayRef<SMLoc> Loc) override {
161 // Evaluate the arguments individually.
162 SmallVector<RecSet, 4> Args(Expr->getNumArgs());
163 unsigned MaxSize = 0;
164 for (unsigned i = 0, e = Expr->getNumArgs(); i != e; ++i) {
165 ST.evaluate(Expr->getArg(i), Args[i], Loc);
166 MaxSize = std::max(MaxSize, unsigned(Args[i].size()));
168 // Interleave arguments into Elts.
169 for (unsigned n = 0; n != MaxSize; ++n)
170 for (unsigned i = 0, e = Expr->getNumArgs(); i != e; ++i)
171 if (n < Args[i].size())
172 Elts.insert(Args[i][n]);
176 // (sequence "Format", From, To) Generate a sequence of records by name.
177 struct SequenceOp : public SetTheory::Operator {
178 void apply(SetTheory &ST, DagInit *Expr, RecSet &Elts,
179 ArrayRef<SMLoc> Loc) override {
181 if (Expr->arg_size() > 4)
182 PrintFatalError(Loc, "Bad args to (sequence \"Format\", From, To): " +
183 Expr->getAsString());
184 else if (Expr->arg_size() == 4) {
185 if (IntInit *II = dyn_cast<IntInit>(Expr->arg_begin()[3])) {
186 Step = II->getValue();
188 PrintFatalError(Loc, "Stride must be an integer: " +
189 Expr->getAsString());
193 if (StringInit *SI = dyn_cast<StringInit>(Expr->arg_begin()[0]))
194 Format = SI->getValue();
196 PrintFatalError(Loc, "Format must be a string: " + Expr->getAsString());
199 if (IntInit *II = dyn_cast<IntInit>(Expr->arg_begin()[1]))
200 From = II->getValue();
202 PrintFatalError(Loc, "From must be an integer: " + Expr->getAsString());
203 if (From < 0 || From >= (1 << 30))
204 PrintFatalError(Loc, "From out of range");
206 if (IntInit *II = dyn_cast<IntInit>(Expr->arg_begin()[2]))
209 PrintFatalError(Loc, "To must be an integer: " + Expr->getAsString());
210 if (To < 0 || To >= (1 << 30))
211 PrintFatalError(Loc, "To out of range");
213 RecordKeeper &Records =
214 cast<DefInit>(Expr->getOperator())->getDef()->getRecords();
216 Step *= From <= To ? 1 : -1;
218 if (Step > 0 && From > To)
220 else if (Step < 0 && From < To)
223 raw_string_ostream OS(Name);
224 OS << format(Format.c_str(), unsigned(From));
225 Record *Rec = Records.getDef(OS.str());
227 PrintFatalError(Loc, "No def named '" + Name + "': " +
228 Expr->getAsString());
229 // Try to reevaluate Rec in case it is a set.
230 if (const RecVec *Result = ST.expand(Rec))
231 Elts.insert(Result->begin(), Result->end());
240 // Expand a Def into a set by evaluating one of its fields.
241 struct FieldExpander : public SetTheory::Expander {
244 FieldExpander(StringRef fn) : FieldName(fn) {}
246 void expand(SetTheory &ST, Record *Def, RecSet &Elts) override {
247 ST.evaluate(Def->getValueInit(FieldName), Elts, Def->getLoc());
251 } // end anonymous namespace
253 // Pin the vtables to this file.
254 void SetTheory::Operator::anchor() {}
255 void SetTheory::Expander::anchor() {}
257 SetTheory::SetTheory() {
258 addOperator("add", std::make_unique<AddOp>());
259 addOperator("sub", std::make_unique<SubOp>());
260 addOperator("and", std::make_unique<AndOp>());
261 addOperator("shl", std::make_unique<ShlOp>());
262 addOperator("trunc", std::make_unique<TruncOp>());
263 addOperator("rotl", std::make_unique<RotOp>(false));
264 addOperator("rotr", std::make_unique<RotOp>(true));
265 addOperator("decimate", std::make_unique<DecimateOp>());
266 addOperator("interleave", std::make_unique<InterleaveOp>());
267 addOperator("sequence", std::make_unique<SequenceOp>());
270 void SetTheory::addOperator(StringRef Name, std::unique_ptr<Operator> Op) {
271 Operators[Name] = std::move(Op);
274 void SetTheory::addExpander(StringRef ClassName, std::unique_ptr<Expander> E) {
275 Expanders[ClassName] = std::move(E);
278 void SetTheory::addFieldExpander(StringRef ClassName, StringRef FieldName) {
279 addExpander(ClassName, std::make_unique<FieldExpander>(FieldName));
282 void SetTheory::evaluate(Init *Expr, RecSet &Elts, ArrayRef<SMLoc> Loc) {
283 // A def in a list can be a just an element, or it may expand.
284 if (DefInit *Def = dyn_cast<DefInit>(Expr)) {
285 if (const RecVec *Result = expand(Def->getDef()))
286 return Elts.insert(Result->begin(), Result->end());
287 Elts.insert(Def->getDef());
291 // Lists simply expand.
292 if (ListInit *LI = dyn_cast<ListInit>(Expr))
293 return evaluate(LI->begin(), LI->end(), Elts, Loc);
295 // Anything else must be a DAG.
296 DagInit *DagExpr = dyn_cast<DagInit>(Expr);
298 PrintFatalError(Loc, "Invalid set element: " + Expr->getAsString());
299 DefInit *OpInit = dyn_cast<DefInit>(DagExpr->getOperator());
301 PrintFatalError(Loc, "Bad set expression: " + Expr->getAsString());
302 auto I = Operators.find(OpInit->getDef()->getName());
303 if (I == Operators.end())
304 PrintFatalError(Loc, "Unknown set operator: " + Expr->getAsString());
305 I->second->apply(*this, DagExpr, Elts, Loc);
308 const RecVec *SetTheory::expand(Record *Set) {
309 // Check existing entries for Set and return early.
310 ExpandMap::iterator I = Expansions.find(Set);
311 if (I != Expansions.end())
314 // This is the first time we see Set. Find a suitable expander.
315 ArrayRef<std::pair<Record *, SMRange>> SC = Set->getSuperClasses();
316 for (const auto &SCPair : SC) {
317 // Skip unnamed superclasses.
318 if (!isa<StringInit>(SCPair.first->getNameInit()))
320 auto I = Expanders.find(SCPair.first->getName());
321 if (I != Expanders.end()) {
322 // This breaks recursive definitions.
323 RecVec &EltVec = Expansions[Set];
325 I->second->expand(*this, Set, Elts);
326 EltVec.assign(Elts.begin(), Elts.end());
331 // Set is not expandable.