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/SlotCalculator.h"
13 #include "llvm/Analysis/ConstantsScanner.h"
14 #include "llvm/Module.h"
15 #include "llvm/iOther.h"
16 #include "llvm/Constant.h"
17 #include "llvm/DerivedTypes.h"
18 #include "llvm/SymbolTable.h"
19 #include "Support/DepthFirstIterator.h"
20 #include "Support/STLExtras.h"
24 #define SC_DEBUG(X) cerr << X
29 SlotCalculator::SlotCalculator(const Module *M, bool IgnoreNamed) {
30 IgnoreNamedNodes = IgnoreNamed;
33 // Preload table... Make sure that all of the primitive types are in the table
34 // and that their Primitive ID is equal to their slot #
36 for (unsigned i = 0; i < Type::FirstDerivedTyID; ++i) {
37 assert(Type::getPrimitiveType((Type::PrimitiveID)i));
38 insertVal(Type::getPrimitiveType((Type::PrimitiveID)i), true);
41 if (M == 0) return; // Empty table...
45 SlotCalculator::SlotCalculator(const Function *M, bool IgnoreNamed) {
46 IgnoreNamedNodes = IgnoreNamed;
47 TheModule = M ? M->getParent() : 0;
49 // Preload table... Make sure that all of the primitive types are in the table
50 // and that their Primitive ID is equal to their slot #
52 for (unsigned i = 0; i < Type::FirstDerivedTyID; ++i) {
53 assert(Type::getPrimitiveType((Type::PrimitiveID)i));
54 insertVal(Type::getPrimitiveType((Type::PrimitiveID)i), true);
57 if (TheModule == 0) return; // Empty table...
59 processModule(); // Process module level stuff
60 incorporateFunction(M); // Start out in incorporated state
64 // processModule - Process all of the module level function declarations and
65 // types that are available.
67 void SlotCalculator::processModule() {
68 SC_DEBUG("begin processModule!\n");
70 // Add all of the constants that the global variables might refer to first.
72 for (Module::const_giterator I = TheModule->gbegin(), E = TheModule->gend();
74 if (I->hasInitializer())
75 insertValue(I->getInitializer());
77 // Add all of the global variables to the value table...
79 for(Module::const_giterator I = TheModule->gbegin(), E = TheModule->gend();
83 // Scavenge the types out of the functions, then add the functions themselves
84 // to the value table...
86 for(Module::const_iterator I = TheModule->begin(), E = TheModule->end();
90 // Insert constants that are named at module level into the slot pool so that
91 // the module symbol table can refer to them...
93 if (!IgnoreNamedNodes) {
94 SC_DEBUG("Inserting SymbolTable values:\n");
95 processSymbolTable(&TheModule->getSymbolTable());
98 SC_DEBUG("end processModule!\n");
101 // processSymbolTable - Insert all of the values in the specified symbol table
102 // into the values table...
104 void SlotCalculator::processSymbolTable(const SymbolTable *ST) {
105 for (SymbolTable::const_iterator I = ST->begin(), E = ST->end(); I != E; ++I)
106 for (SymbolTable::type_const_iterator TI = I->second.begin(),
107 TE = I->second.end(); TI != TE; ++TI)
108 insertValue(TI->second);
111 void SlotCalculator::processSymbolTableConstants(const SymbolTable *ST) {
112 for (SymbolTable::const_iterator I = ST->begin(), E = ST->end(); I != E; ++I)
113 for (SymbolTable::type_const_iterator TI = I->second.begin(),
114 TE = I->second.end(); TI != TE; ++TI)
115 if (isa<Constant>(TI->second))
116 insertValue(TI->second);
120 void SlotCalculator::incorporateFunction(const Function *M) {
121 assert(ModuleLevel.size() == 0 && "Module already incorporated!");
123 SC_DEBUG("begin processFunction!\n");
125 // Save the Table state before we process the function...
126 for (unsigned i = 0; i < Table.size(); ++i)
127 ModuleLevel.push_back(Table[i].size());
129 SC_DEBUG("Inserting function arguments\n");
131 // Iterate over function arguments, adding them to the value table...
132 for(Function::const_aiterator I = M->abegin(), E = M->aend(); I != E; ++I)
135 // Iterate over all of the instructions in the function, looking for constant
136 // values that are referenced. Add these to the value pools before any
137 // nonconstant values. This will be turned into the constant pool for the
140 if (!IgnoreNamedNodes) { // Assembly writer does not need this!
141 SC_DEBUG("Inserting function constants:\n";
142 for (constant_iterator I = constant_begin(M), E = constant_end(M);
144 cerr << " " << *I->getType()
145 << " " << *I << "\n";
148 // Emit all of the constants that are being used by the instructions in the
150 for_each(constant_begin(M), constant_end(M),
151 bind_obj(this, &SlotCalculator::insertValue));
153 // If there is a symbol table, it is possible that the user has names for
154 // constants that are not being used. In this case, we will have problems
155 // if we don't emit the constants now, because otherwise we will get
156 // symboltable references to constants not in the output. Scan for these
159 processSymbolTableConstants(&M->getSymbolTable());
162 SC_DEBUG("Inserting Labels:\n");
164 // Iterate over basic blocks, adding them to the value table...
165 for (Function::const_iterator I = M->begin(), E = M->end(); I != E; ++I)
167 /* for_each(M->begin(), M->end(),
168 bind_obj(this, &SlotCalculator::insertValue));*/
170 SC_DEBUG("Inserting Instructions:\n");
172 // Add all of the instructions to the type planes...
173 for_each(inst_begin(M), inst_end(M),
174 bind_obj(this, &SlotCalculator::insertValue));
176 if (!IgnoreNamedNodes) {
177 SC_DEBUG("Inserting SymbolTable values:\n");
178 processSymbolTable(&M->getSymbolTable());
181 SC_DEBUG("end processFunction!\n");
184 void SlotCalculator::purgeFunction() {
185 assert(ModuleLevel.size() != 0 && "Module not incorporated!");
186 unsigned NumModuleTypes = ModuleLevel.size();
188 SC_DEBUG("begin purgeFunction!\n");
190 // First, remove values from existing type planes
191 for (unsigned i = 0; i < NumModuleTypes; ++i) {
192 unsigned ModuleSize = ModuleLevel[i]; // Size of plane before function came
193 TypePlane &CurPlane = Table[i];
194 //SC_DEBUG("Processing Plane " <<i<< " of size " << CurPlane.size() <<"\n");
196 while (CurPlane.size() != ModuleSize) {
197 //SC_DEBUG(" Removing [" << i << "] Value=" << CurPlane.back() << "\n");
198 std::map<const Value *, unsigned>::iterator NI =
199 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 function...
210 while (NumModuleTypes != Table.size()) {
211 TypePlane &Plane = Table.back();
212 SC_DEBUG("Removing Plane " << (Table.size()-1) << " of size "
213 << Plane.size() << "\n");
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 purgeFunction!\n");
225 int SlotCalculator::getValSlot(const Value *D) const {
226 std::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<Constant>(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::const_op_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) {
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<Constant>(D)) && !isa<Type>(D))) {
263 SC_DEBUG("ignored value " << D << "\n");
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() << "\n");
295 int Slot = doInsertVal(SubTy);
296 SC_DEBUG(" Inserted subtype: " << SubTy->getDescription() <<
297 " slot=" << Slot << "\n");
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 = Constant, T = Type, F = Function, o = other
340 SC_DEBUG((isa<GlobalVariable>(D) ? "G" : (isa<Constant>(D) ? "C" :
341 (isa<Type>(D) ? "T" : (isa<Function>(D) ? "F" : "o")))));
343 return (int)DestSlot;