1 //===-- SlotCalculator.cpp - Calculate what slots values land in ------------=//
3 // This file implements a useful analysis step to figure out what numbered
4 // slots values in a program will land in (keeping track of per plane
5 // information as required.
7 // This is used primarily for when writing a file to disk, either in bytecode
10 //===----------------------------------------------------------------------===//
12 #include "llvm/Analysis/SlotCalculator.h"
13 #include "llvm/Analysis/ConstantsScanner.h"
14 #include "llvm/Method.h"
15 #include "llvm/GlobalVariable.h"
16 #include "llvm/Module.h"
17 #include "llvm/BasicBlock.h"
18 #include "llvm/ConstPoolVals.h"
19 #include "llvm/iOther.h"
20 #include "llvm/DerivedTypes.h"
21 #include "llvm/SymbolTable.h"
22 #include "llvm/Support/STLExtras.h"
23 #include "llvm/Support/DepthFirstIterator.h"
27 #define SC_DEBUG(X) cerr << X
32 SlotCalculator::SlotCalculator(const Module *M, bool IgnoreNamed) {
33 IgnoreNamedNodes = IgnoreNamed;
36 // Preload table... Make sure that all of the primitive types are in the table
37 // and that their Primitive ID is equal to their slot #
39 for (unsigned i = 0; i < Type::FirstDerivedTyID; ++i) {
40 assert(Type::getPrimitiveType((Type::PrimitiveID)i));
41 insertVal(Type::getPrimitiveType((Type::PrimitiveID)i), true);
44 if (M == 0) return; // Empty table...
48 SlotCalculator::SlotCalculator(const Method *M, bool IgnoreNamed) {
49 IgnoreNamedNodes = IgnoreNamed;
50 TheModule = M ? M->getParent() : 0;
52 // Preload table... Make sure that all of the primitive types are in the table
53 // and that their Primitive ID is equal to their slot #
55 for (unsigned i = 0; i < Type::FirstDerivedTyID; ++i) {
56 assert(Type::getPrimitiveType((Type::PrimitiveID)i));
57 insertVal(Type::getPrimitiveType((Type::PrimitiveID)i), true);
60 if (TheModule == 0) return; // Empty table...
62 processModule(); // Process module level stuff
63 incorporateMethod(M); // Start out in incorporated state
67 // processModule - Process all of the module level method declarations and
68 // types that are available.
70 void SlotCalculator::processModule() {
71 SC_DEBUG("begin processModule!\n");
73 // Add all of the constants that the global variables might refer to first.
75 for (Module::const_giterator I = TheModule->gbegin(), E = TheModule->gend();
77 if ((*I)->hasInitializer())
78 insertValue((*I)->getInitializer());
81 // Add all of the global variables to the value table...
83 for_each(TheModule->gbegin(), TheModule->gend(),
84 bind_obj(this, &SlotCalculator::insertValue));
86 // Scavenge the types out of the methods, then add the methods themselves to
89 for_each(TheModule->begin(), TheModule->end(), // Insert methods...
90 bind_obj(this, &SlotCalculator::insertValue));
92 // Insert constants that are named at module level into the slot pool so that
93 // the module symbol table can refer to them...
95 if (TheModule->hasSymbolTable() && !IgnoreNamedNodes) {
96 SC_DEBUG("Inserting SymbolTable values:\n");
97 processSymbolTable(TheModule->getSymbolTable());
100 SC_DEBUG("end processModule!\n");
103 // processSymbolTable - Insert all of the values in the specified symbol table
104 // into the values table...
106 void SlotCalculator::processSymbolTable(const SymbolTable *ST) {
107 for (SymbolTable::const_iterator I = ST->begin(), E = ST->end(); I != E; ++I)
108 for (SymbolTable::type_const_iterator TI = I->second.begin(),
109 TE = I->second.end(); TI != TE; ++TI)
110 insertValue(TI->second);
113 void SlotCalculator::processSymbolTableConstants(const SymbolTable *ST) {
114 for (SymbolTable::const_iterator I = ST->begin(), E = ST->end(); I != E; ++I)
115 for (SymbolTable::type_const_iterator TI = I->second.begin(),
116 TE = I->second.end(); TI != TE; ++TI)
117 if (isa<ConstPoolVal>(TI->second))
118 insertValue(TI->second);
122 void SlotCalculator::incorporateMethod(const Method *M) {
123 assert(ModuleLevel.size() == 0 && "Module already incorporated!");
125 SC_DEBUG("begin processMethod!\n");
127 // Save the Table state before we process the method...
128 for (unsigned i = 0; i < Table.size(); ++i)
129 ModuleLevel.push_back(Table[i].size());
131 SC_DEBUG("Inserting method arguments\n");
133 // Iterate over method arguments, adding them to the value table...
134 for_each(M->getArgumentList().begin(), M->getArgumentList().end(),
135 bind_obj(this, &SlotCalculator::insertValue));
137 // Iterate over all of the instructions in the method, looking for constant
138 // values that are referenced. Add these to the value pools before any
139 // nonconstant values. This will be turned into the constant pool for the
142 if (!IgnoreNamedNodes) { // Assembly writer does not need this!
143 SC_DEBUG("Inserting method constants:\n";
144 for (constant_iterator I = constant_begin(M), E = constant_end(M);
146 cerr << " " << I->getType()->getDescription()
147 << " " << I->getStrValue() << endl;
150 // Emit all of the constants that are being used by the instructions in the
152 for_each(constant_begin(M), constant_end(M),
153 bind_obj(this, &SlotCalculator::insertValue));
155 // If there is a symbol table, it is possible that the user has names for
156 // constants that are not being used. In this case, we will have problems
157 // if we don't emit the constants now, because otherwise we will get
158 // symboltable references to constants not in the output. Scan for these
161 if (M->hasSymbolTable())
162 processSymbolTableConstants(M->getSymbolTable());
165 SC_DEBUG("Inserting Labels:\n");
167 // Iterate over basic blocks, adding them to the value table...
168 for_each(M->begin(), M->end(),
169 bind_obj(this, &SlotCalculator::insertValue));
171 SC_DEBUG("Inserting Instructions:\n");
173 // Add all of the instructions to the type planes...
174 for_each(M->inst_begin(), M->inst_end(),
175 bind_obj(this, &SlotCalculator::insertValue));
177 if (M->hasSymbolTable() && !IgnoreNamedNodes) {
178 SC_DEBUG("Inserting SymbolTable values:\n");
179 processSymbolTable(M->getSymbolTable());
182 SC_DEBUG("end processMethod!\n");
185 void SlotCalculator::purgeMethod() {
186 assert(ModuleLevel.size() != 0 && "Module not incorporated!");
187 unsigned NumModuleTypes = ModuleLevel.size();
189 SC_DEBUG("begin purgeMethod!\n");
191 // First, remove values from existing type planes
192 for (unsigned i = 0; i < NumModuleTypes; ++i) {
193 unsigned ModuleSize = ModuleLevel[i]; // Size of plane before method came
194 TypePlane &CurPlane = Table[i];
195 //SC_DEBUG("Processing Plane " <<i<< " of size " << CurPlane.size() <<endl);
197 while (CurPlane.size() != ModuleSize) {
198 //SC_DEBUG(" Removing [" << i << "] Value=" << CurPlane.back() << "\n");
199 map<const Value *, unsigned>::iterator NI = NodeMap.find(CurPlane.back());
200 assert(NI != NodeMap.end() && "Node not in nodemap?");
201 NodeMap.erase(NI); // Erase from nodemap
202 CurPlane.pop_back(); // Shrink plane
206 // We don't need this state anymore, free it up.
209 // Next, remove any type planes defined by the method...
210 while (NumModuleTypes != Table.size()) {
211 TypePlane &Plane = Table.back();
212 SC_DEBUG("Removing Plane " << (Table.size()-1) << " of size "
213 << Plane.size() << endl);
214 while (Plane.size()) {
215 NodeMap.erase(NodeMap.find(Plane.back())); // Erase from nodemap
216 Plane.pop_back(); // Shrink plane
219 Table.pop_back(); // Nuke the plane, we don't like it.
222 SC_DEBUG("end purgeMethod!\n");
225 int SlotCalculator::getValSlot(const Value *D) const {
226 map<const Value*, unsigned>::const_iterator I = NodeMap.find(D);
227 if (I == NodeMap.end()) return -1;
229 return (int)I->second;
233 int SlotCalculator::insertValue(const Value *D) {
234 if (isa<ConstPoolVal>(D) || isa<GlobalVariable>(D)) {
235 const User *U = cast<const User>(D);
236 // This makes sure that if a constant has uses (for example an array
237 // of const ints), that they are inserted also. Same for global variable
240 for(User::op_const_iterator I = U->op_begin(), E = U->op_end(); I != E; ++I)
241 if (!isa<GlobalValue>(*I)) // Don't chain insert global values
245 int SlotNo = getValSlot(D); // Check to see if it's already in!
246 if (SlotNo != -1) return SlotNo;
251 int SlotCalculator::insertVal(const Value *D, bool dontIgnore = false) {
252 assert(D && "Can't insert a null value!");
253 assert(getValSlot(D) == -1 && "Value is already in the table!");
255 // If this node does not contribute to a plane, or if the node has a
256 // name and we don't want names, then ignore the silly node... Note that types
257 // do need slot numbers so that we can keep track of where other values land.
259 if (!dontIgnore) // Don't ignore nonignorables!
260 if (D->getType() == Type::VoidTy || // Ignore void type nodes
261 (IgnoreNamedNodes && // Ignore named and constants
262 (D->hasName() || isa<ConstPoolVal>(D)) && !isa<Type>(D))) {
263 SC_DEBUG("ignored value " << D << endl);
264 return -1; // We do need types unconditionally though
267 // If it's a type, make sure that all subtypes of the type are included...
268 if (const Type *TheTy = dyn_cast<const Type>(D)) {
270 // Insert the current type before any subtypes. This is important because
271 // recursive types elements are inserted in a bottom up order. Changing
272 // this here can break things. For example:
274 // global { \2 * } { { \2 }* null }
277 if ((ResultSlot = getValSlot(TheTy)) == -1) {
278 ResultSlot = doInsertVal(TheTy);
279 SC_DEBUG(" Inserted type: " << TheTy->getDescription() << " slot=" <<
283 // Loop over any contained types in the definition... in reverse depth first
284 // order. This assures that all of the leafs of a type are output before
285 // the type itself is. This also assures us that we will not hit infinite
286 // recursion on recursive types...
288 for (df_iterator<const Type*> I = df_begin(TheTy, true),
289 E = df_end(TheTy); I != E; ++I)
291 // If we haven't seen this sub type before, add it to our type table!
292 const Type *SubTy = *I;
293 if (getValSlot(SubTy) == -1) {
294 SC_DEBUG(" Inserting subtype: " << SubTy->getDescription() << endl);
295 int Slot = doInsertVal(SubTy);
296 SC_DEBUG(" Inserted subtype: " << SubTy->getDescription() <<
297 " slot=" << Slot << endl);
303 // Okay, everything is happy, actually insert the silly value now...
304 return doInsertVal(D);
308 // doInsertVal - This is a small helper function to be called only be insertVal.
310 int SlotCalculator::doInsertVal(const Value *D) {
311 const Type *Typ = D->getType();
314 // Used for debugging DefSlot=-1 assertion...
315 //if (Typ == Type::TypeTy)
316 // cerr << "Inserting type '" << cast<Type>(D)->getDescription() << "'!\n";
318 if (Typ->isDerivedType()) {
319 int DefSlot = getValSlot(Typ);
320 if (DefSlot == -1) { // Have we already entered this type?
321 // Nope, this is the first we have seen the type, process it.
322 DefSlot = insertVal(Typ, true);
323 assert(DefSlot != -1 && "ProcessType returned -1 for a type?");
325 Ty = (unsigned)DefSlot;
327 Ty = Typ->getPrimitiveID();
330 if (Table.size() <= Ty) // Make sure we have the type plane allocated...
331 Table.resize(Ty+1, TypePlane());
333 // Insert node into table and NodeMap...
334 unsigned DestSlot = NodeMap[D] = Table[Ty].size();
335 Table[Ty].push_back(D);
337 SC_DEBUG(" Inserting value [" << Ty << "] = " << D << " slot=" <<
339 // G = Global, C = ConstPoolVal, T = Type, M = Method, o = other
340 SC_DEBUG((isa<GlobalVariable>(D) ? "G" : (isa<ConstPoolVal>(D) ? "C" :
341 (isa<Type>(D) ? "T" : (isa<Method>(D) ? "M" : "o")))));
343 return (int)DestSlot;