1 //===- CodeGenRegisters.cpp - Register and RegisterClass Info -------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines structures to encapsulate information gleaned from the
11 // target register and register class definitions.
13 //===----------------------------------------------------------------------===//
15 #include "CodeGenRegisters.h"
16 #include "CodeGenTarget.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/ADT/StringExtras.h"
22 //===----------------------------------------------------------------------===//
24 //===----------------------------------------------------------------------===//
26 CodeGenRegister::CodeGenRegister(Record *R, unsigned Enum)
29 CostPerUse(R->getValueAsInt("CostPerUse")),
30 SubRegsComplete(false)
33 const std::string &CodeGenRegister::getName() const {
34 return TheDef->getName();
39 CodeGenRegister *SubReg;
40 Record *First, *Second;
41 Orphan(CodeGenRegister *r, Record *a, Record *b)
42 : SubReg(r), First(a), Second(b) {}
46 const CodeGenRegister::SubRegMap &
47 CodeGenRegister::getSubRegs(CodeGenRegBank &RegBank) {
48 // Only compute this map once.
51 SubRegsComplete = true;
53 std::vector<Record*> SubList = TheDef->getValueAsListOfDefs("SubRegs");
54 std::vector<Record*> Indices = TheDef->getValueAsListOfDefs("SubRegIndices");
55 if (SubList.size() != Indices.size())
56 throw TGError(TheDef->getLoc(), "Register " + getName() +
57 " SubRegIndices doesn't match SubRegs");
59 // First insert the direct subregs and make sure they are fully indexed.
60 for (unsigned i = 0, e = SubList.size(); i != e; ++i) {
61 CodeGenRegister *SR = RegBank.getReg(SubList[i]);
62 if (!SubRegs.insert(std::make_pair(Indices[i], SR)).second)
63 throw TGError(TheDef->getLoc(), "SubRegIndex " + Indices[i]->getName() +
64 " appears twice in Register " + getName());
67 // Keep track of inherited subregs and how they can be reached.
68 SmallVector<Orphan, 8> Orphans;
70 // Clone inherited subregs and place duplicate entries on Orphans.
71 // Here the order is important - earlier subregs take precedence.
72 for (unsigned i = 0, e = SubList.size(); i != e; ++i) {
73 CodeGenRegister *SR = RegBank.getReg(SubList[i]);
74 const SubRegMap &Map = SR->getSubRegs(RegBank);
75 for (SubRegMap::const_iterator SI = Map.begin(), SE = Map.end(); SI != SE;
77 if (!SubRegs.insert(*SI).second)
78 Orphans.push_back(Orphan(SI->second, Indices[i], SI->first));
81 // Process the composites.
82 ListInit *Comps = TheDef->getValueAsListInit("CompositeIndices");
83 for (unsigned i = 0, e = Comps->size(); i != e; ++i) {
84 DagInit *Pat = dynamic_cast<DagInit*>(Comps->getElement(i));
86 throw TGError(TheDef->getLoc(), "Invalid dag '" +
87 Comps->getElement(i)->getAsString() +
88 "' in CompositeIndices");
89 DefInit *BaseIdxInit = dynamic_cast<DefInit*>(Pat->getOperator());
90 if (!BaseIdxInit || !BaseIdxInit->getDef()->isSubClassOf("SubRegIndex"))
91 throw TGError(TheDef->getLoc(), "Invalid SubClassIndex in " +
94 // Resolve list of subreg indices into R2.
95 CodeGenRegister *R2 = this;
96 for (DagInit::const_arg_iterator di = Pat->arg_begin(),
97 de = Pat->arg_end(); di != de; ++di) {
98 DefInit *IdxInit = dynamic_cast<DefInit*>(*di);
99 if (!IdxInit || !IdxInit->getDef()->isSubClassOf("SubRegIndex"))
100 throw TGError(TheDef->getLoc(), "Invalid SubClassIndex in " +
102 const SubRegMap &R2Subs = R2->getSubRegs(RegBank);
103 SubRegMap::const_iterator ni = R2Subs.find(IdxInit->getDef());
104 if (ni == R2Subs.end())
105 throw TGError(TheDef->getLoc(), "Composite " + Pat->getAsString() +
106 " refers to bad index in " + R2->getName());
110 // Insert composite index. Allow overriding inherited indices etc.
111 SubRegs[BaseIdxInit->getDef()] = R2;
113 // R2 is no longer an orphan.
114 for (unsigned j = 0, je = Orphans.size(); j != je; ++j)
115 if (Orphans[j].SubReg == R2)
116 Orphans[j].SubReg = 0;
119 // Now Orphans contains the inherited subregisters without a direct index.
120 // Create inferred indexes for all missing entries.
121 for (unsigned i = 0, e = Orphans.size(); i != e; ++i) {
122 Orphan &O = Orphans[i];
125 SubRegs[RegBank.getCompositeSubRegIndex(O.First, O.Second, true)] =
131 //===----------------------------------------------------------------------===//
132 // CodeGenRegisterClass
133 //===----------------------------------------------------------------------===//
135 CodeGenRegisterClass::CodeGenRegisterClass(Record *R) : TheDef(R) {
136 // Rename anonymous register classes.
137 if (R->getName().size() > 9 && R->getName()[9] == '.') {
138 static unsigned AnonCounter = 0;
139 R->setName("AnonRegClass_"+utostr(AnonCounter++));
142 std::vector<Record*> TypeList = R->getValueAsListOfDefs("RegTypes");
143 for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
144 Record *Type = TypeList[i];
145 if (!Type->isSubClassOf("ValueType"))
146 throw "RegTypes list member '" + Type->getName() +
147 "' does not derive from the ValueType class!";
148 VTs.push_back(getValueType(Type));
150 assert(!VTs.empty() && "RegisterClass must contain at least one ValueType!");
152 std::vector<Record*> RegList = R->getValueAsListOfDefs("MemberList");
153 for (unsigned i = 0, e = RegList.size(); i != e; ++i) {
154 Record *Reg = RegList[i];
155 if (!Reg->isSubClassOf("Register"))
156 throw "Register Class member '" + Reg->getName() +
157 "' does not derive from the Register class!";
158 Elements.push_back(Reg);
161 // SubRegClasses is a list<dag> containing (RC, subregindex, ...) dags.
162 ListInit *SRC = R->getValueAsListInit("SubRegClasses");
163 for (ListInit::const_iterator i = SRC->begin(), e = SRC->end(); i != e; ++i) {
164 DagInit *DAG = dynamic_cast<DagInit*>(*i);
165 if (!DAG) throw "SubRegClasses must contain DAGs";
166 DefInit *DAGOp = dynamic_cast<DefInit*>(DAG->getOperator());
168 if (!DAGOp || !(RCRec = DAGOp->getDef())->isSubClassOf("RegisterClass"))
169 throw "Operator '" + DAG->getOperator()->getAsString() +
170 "' in SubRegClasses is not a RegisterClass";
171 // Iterate over args, all SubRegIndex instances.
172 for (DagInit::const_arg_iterator ai = DAG->arg_begin(), ae = DAG->arg_end();
174 DefInit *Idx = dynamic_cast<DefInit*>(*ai);
176 if (!Idx || !(IdxRec = Idx->getDef())->isSubClassOf("SubRegIndex"))
177 throw "Argument '" + (*ai)->getAsString() +
178 "' in SubRegClasses is not a SubRegIndex";
179 if (!SubRegClasses.insert(std::make_pair(IdxRec, RCRec)).second)
180 throw "SubRegIndex '" + IdxRec->getName() + "' mentioned twice";
184 // Allow targets to override the size in bits of the RegisterClass.
185 unsigned Size = R->getValueAsInt("Size");
187 Namespace = R->getValueAsString("Namespace");
188 SpillSize = Size ? Size : EVT(VTs[0]).getSizeInBits();
189 SpillAlignment = R->getValueAsInt("Alignment");
190 CopyCost = R->getValueAsInt("CopyCost");
191 Allocatable = R->getValueAsBit("isAllocatable");
192 MethodBodies = R->getValueAsCode("MethodBodies");
193 MethodProtos = R->getValueAsCode("MethodProtos");
196 const std::string &CodeGenRegisterClass::getName() const {
197 return TheDef->getName();
200 //===----------------------------------------------------------------------===//
202 //===----------------------------------------------------------------------===//
204 CodeGenRegBank::CodeGenRegBank(RecordKeeper &Records) : Records(Records) {
205 // Read in the user-defined (named) sub-register indices.
206 // More indices will be synthesized later.
207 SubRegIndices = Records.getAllDerivedDefinitions("SubRegIndex");
208 std::sort(SubRegIndices.begin(), SubRegIndices.end(), LessRecord());
209 NumNamedIndices = SubRegIndices.size();
211 // Read in the register definitions.
212 std::vector<Record*> Regs = Records.getAllDerivedDefinitions("Register");
213 std::sort(Regs.begin(), Regs.end(), LessRecord());
214 Registers.reserve(Regs.size());
215 // Assign the enumeration values.
216 for (unsigned i = 0, e = Regs.size(); i != e; ++i)
217 Registers.push_back(CodeGenRegister(Regs[i], i + 1));
220 CodeGenRegister *CodeGenRegBank::getReg(Record *Def) {
222 for (unsigned i = 0, e = Registers.size(); i != e; ++i)
223 Def2Reg[Registers[i].TheDef] = &Registers[i];
225 if (CodeGenRegister *Reg = Def2Reg[Def])
228 throw TGError(Def->getLoc(), "Not a known Register!");
231 Record *CodeGenRegBank::getCompositeSubRegIndex(Record *A, Record *B,
233 // Look for an existing entry.
234 Record *&Comp = Composite[std::make_pair(A, B)];
238 // None exists, synthesize one.
239 std::string Name = A->getName() + "_then_" + B->getName();
240 Comp = new Record(Name, SMLoc(), Records);
241 Records.addDef(Comp);
242 SubRegIndices.push_back(Comp);
246 unsigned CodeGenRegBank::getSubRegIndexNo(Record *idx) {
247 std::vector<Record*>::const_iterator i =
248 std::find(SubRegIndices.begin(), SubRegIndices.end(), idx);
249 assert(i != SubRegIndices.end() && "Not a SubRegIndex");
250 return (i - SubRegIndices.begin()) + 1;
253 void CodeGenRegBank::computeComposites() {
254 // Precompute all sub-register maps. This will create Composite entries for
255 // all inferred sub-register indices.
256 for (unsigned i = 0, e = Registers.size(); i != e; ++i)
257 Registers[i].getSubRegs(*this);
259 for (unsigned i = 0, e = Registers.size(); i != e; ++i) {
260 CodeGenRegister *Reg1 = &Registers[i];
261 const CodeGenRegister::SubRegMap &SRM1 = Reg1->getSubRegs(*this);
262 for (CodeGenRegister::SubRegMap::const_iterator i1 = SRM1.begin(),
263 e1 = SRM1.end(); i1 != e1; ++i1) {
264 Record *Idx1 = i1->first;
265 CodeGenRegister *Reg2 = i1->second;
266 // Ignore identity compositions.
269 const CodeGenRegister::SubRegMap &SRM2 = Reg2->getSubRegs(*this);
270 // Try composing Idx1 with another SubRegIndex.
271 for (CodeGenRegister::SubRegMap::const_iterator i2 = SRM2.begin(),
272 e2 = SRM2.end(); i2 != e2; ++i2) {
273 std::pair<Record*, Record*> IdxPair(Idx1, i2->first);
274 CodeGenRegister *Reg3 = i2->second;
275 // Ignore identity compositions.
278 // OK Reg1:IdxPair == Reg3. Find the index with Reg:Idx == Reg3.
279 for (CodeGenRegister::SubRegMap::const_iterator i1d = SRM1.begin(),
280 e1d = SRM1.end(); i1d != e1d; ++i1d) {
281 if (i1d->second == Reg3) {
282 std::pair<CompositeMap::iterator, bool> Ins =
283 Composite.insert(std::make_pair(IdxPair, i1d->first));
284 // Conflicting composition? Emit a warning but allow it.
285 if (!Ins.second && Ins.first->second != i1d->first) {
286 errs() << "Warning: SubRegIndex " << getQualifiedName(Idx1)
287 << " and " << getQualifiedName(IdxPair.second)
288 << " compose ambiguously as "
289 << getQualifiedName(Ins.first->second) << " or "
290 << getQualifiedName(i1d->first) << "\n";
298 // We don't care about the difference between (Idx1, Idx2) -> Idx2 and invalid
299 // compositions, so remove any mappings of that form.
300 for (CompositeMap::iterator i = Composite.begin(), e = Composite.end();
302 CompositeMap::iterator j = i;
304 if (j->first.second == j->second)
309 void CodeGenRegBank::computeDerivedInfo() {