1 //===-- SlotCalculator.cpp - Calculate what slots values land in ----------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements a useful analysis step to figure out what numbered
11 // slots values in a program will land in (keeping track of per plane
12 // information as required.
14 // This is used primarily for when writing a file to disk, either in bytecode
17 //===----------------------------------------------------------------------===//
19 #include "llvm/SlotCalculator.h"
20 #include "llvm/Analysis/ConstantsScanner.h"
21 #include "llvm/Module.h"
22 #include "llvm/iOther.h"
23 #include "llvm/Constant.h"
24 #include "llvm/DerivedTypes.h"
25 #include "llvm/SymbolTable.h"
26 #include "Support/DepthFirstIterator.h"
27 #include "Support/STLExtras.h"
31 #define SC_DEBUG(X) std::cerr << X
36 SlotCalculator::SlotCalculator(const Module *M, bool IgnoreNamed) {
37 IgnoreNamedNodes = IgnoreNamed;
40 // Preload table... Make sure that all of the primitive types are in the table
41 // and that their Primitive ID is equal to their slot #
43 SC_DEBUG("Inserting primitive types:\n");
44 for (unsigned i = 0; i < Type::FirstDerivedTyID; ++i) {
45 assert(Type::getPrimitiveType((Type::PrimitiveID)i));
46 insertValue(Type::getPrimitiveType((Type::PrimitiveID)i), true);
49 if (M == 0) return; // Empty table...
53 SlotCalculator::SlotCalculator(const Function *M, bool IgnoreNamed) {
54 IgnoreNamedNodes = IgnoreNamed;
55 TheModule = M ? M->getParent() : 0;
57 // Preload table... Make sure that all of the primitive types are in the table
58 // and that their Primitive ID is equal to their slot #
60 SC_DEBUG("Inserting primitive types:\n");
61 for (unsigned i = 0; i < Type::FirstDerivedTyID; ++i) {
62 assert(Type::getPrimitiveType((Type::PrimitiveID)i));
63 insertValue(Type::getPrimitiveType((Type::PrimitiveID)i), true);
66 if (TheModule == 0) return; // Empty table...
68 processModule(); // Process module level stuff
69 incorporateFunction(M); // Start out in incorporated state
73 // processModule - Process all of the module level function declarations and
74 // types that are available.
76 void SlotCalculator::processModule() {
77 SC_DEBUG("begin processModule!\n");
79 // Add all of the global variables to the value table...
81 for (Module::const_giterator I = TheModule->gbegin(), E = TheModule->gend();
85 // Scavenge the types out of the functions, then add the functions themselves
86 // to the value table...
88 for (Module::const_iterator I = TheModule->begin(), E = TheModule->end();
92 // Add all of the module level constants used as initializers
94 for (Module::const_giterator I = TheModule->gbegin(), E = TheModule->gend();
96 if (I->hasInitializer())
97 getOrCreateSlot(I->getInitializer());
99 // Insert constants that are named at module level into the slot pool so that
100 // the module symbol table can refer to them...
102 if (!IgnoreNamedNodes) {
103 SC_DEBUG("Inserting SymbolTable values:\n");
104 processSymbolTable(&TheModule->getSymbolTable());
107 SC_DEBUG("end processModule!\n");
110 // processSymbolTable - Insert all of the values in the specified symbol table
111 // into the values table...
113 void SlotCalculator::processSymbolTable(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 getOrCreateSlot(TI->second);
120 void SlotCalculator::processSymbolTableConstants(const SymbolTable *ST) {
121 for (SymbolTable::const_iterator I = ST->begin(), E = ST->end(); I != E; ++I)
122 for (SymbolTable::type_const_iterator TI = I->second.begin(),
123 TE = I->second.end(); TI != TE; ++TI)
124 if (isa<Constant>(TI->second))
125 getOrCreateSlot(TI->second);
129 void SlotCalculator::incorporateFunction(const Function *F) {
130 assert(ModuleLevel.size() == 0 && "Module already incorporated!");
132 SC_DEBUG("begin processFunction!\n");
134 // Save the Table state before we process the function...
135 for (unsigned i = 0; i < Table.size(); ++i)
136 ModuleLevel.push_back(Table[i].size());
138 SC_DEBUG("Inserting function arguments\n");
140 // Iterate over function arguments, adding them to the value table...
141 for(Function::const_aiterator I = F->abegin(), E = F->aend(); I != E; ++I)
144 // Iterate over all of the instructions in the function, looking for constant
145 // values that are referenced. Add these to the value pools before any
146 // nonconstant values. This will be turned into the constant pool for the
149 if (!IgnoreNamedNodes) { // Assembly writer does not need this!
150 SC_DEBUG("Inserting function constants:\n";
151 for (constant_iterator I = constant_begin(F), E = constant_end(F);
153 std::cerr << " " << *I->getType() << " " << *I << "\n";
156 // Emit all of the constants that are being used by the instructions in the
158 for_each(constant_begin(F), constant_end(F),
159 bind_obj(this, &SlotCalculator::getOrCreateSlot));
161 // If there is a symbol table, it is possible that the user has names for
162 // constants that are not being used. In this case, we will have problems
163 // if we don't emit the constants now, because otherwise we will get
164 // symboltable references to constants not in the output. Scan for these
167 processSymbolTableConstants(&F->getSymbolTable());
170 SC_DEBUG("Inserting Labels:\n");
172 // Iterate over basic blocks, adding them to the value table...
173 for (Function::const_iterator I = F->begin(), E = F->end(); I != E; ++I)
176 SC_DEBUG("Inserting Instructions:\n");
178 // Add all of the instructions to the type planes...
179 for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
180 for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E; ++I) {
182 if (const VANextInst *VAN = dyn_cast<VANextInst>(I))
183 getOrCreateSlot(VAN->getArgType());
186 if (!IgnoreNamedNodes) {
187 SC_DEBUG("Inserting SymbolTable values:\n");
188 processSymbolTable(&F->getSymbolTable());
191 SC_DEBUG("end processFunction!\n");
194 void SlotCalculator::purgeFunction() {
195 assert(ModuleLevel.size() != 0 && "Module not incorporated!");
196 unsigned NumModuleTypes = ModuleLevel.size();
198 SC_DEBUG("begin purgeFunction!\n");
200 // First, remove values from existing type planes
201 for (unsigned i = 0; i < NumModuleTypes; ++i) {
202 unsigned ModuleSize = ModuleLevel[i]; // Size of plane before function came
203 TypePlane &CurPlane = Table[i];
204 //SC_DEBUG("Processing Plane " <<i<< " of size " << CurPlane.size() <<"\n");
206 while (CurPlane.size() != ModuleSize) {
207 //SC_DEBUG(" Removing [" << i << "] Value=" << CurPlane.back() << "\n");
208 std::map<const Value *, unsigned>::iterator NI =
209 NodeMap.find(CurPlane.back());
210 assert(NI != NodeMap.end() && "Node not in nodemap?");
211 NodeMap.erase(NI); // Erase from nodemap
212 CurPlane.pop_back(); // Shrink plane
216 // We don't need this state anymore, free it up.
219 // Next, remove any type planes defined by the function...
220 while (NumModuleTypes != Table.size()) {
221 TypePlane &Plane = Table.back();
222 SC_DEBUG("Removing Plane " << (Table.size()-1) << " of size "
223 << Plane.size() << "\n");
224 while (Plane.size()) {
225 NodeMap.erase(NodeMap.find(Plane.back())); // Erase from nodemap
226 Plane.pop_back(); // Shrink plane
229 Table.pop_back(); // Nuke the plane, we don't like it.
232 SC_DEBUG("end purgeFunction!\n");
235 int SlotCalculator::getSlot(const Value *D) const {
236 std::map<const Value*, unsigned>::const_iterator I = NodeMap.find(D);
237 if (I == NodeMap.end()) return -1;
239 return (int)I->second;
243 int SlotCalculator::getOrCreateSlot(const Value *V) {
244 int SlotNo = getSlot(V); // Check to see if it's already in!
245 if (SlotNo != -1) return SlotNo;
247 if (!isa<GlobalValue>(V))
248 if (const Constant *C = dyn_cast<Constant>(V)) {
249 // This makes sure that if a constant has uses (for example an array of
250 // const ints), that they are inserted also.
252 for (User::const_op_iterator I = C->op_begin(), E = C->op_end();
257 return insertValue(V);
261 int SlotCalculator::insertValue(const Value *D, bool dontIgnore) {
262 assert(D && "Can't insert a null value!");
263 assert(getSlot(D) == -1 && "Value is already in the table!");
265 // If this node does not contribute to a plane, or if the node has a
266 // name and we don't want names, then ignore the silly node... Note that types
267 // do need slot numbers so that we can keep track of where other values land.
269 if (!dontIgnore) // Don't ignore nonignorables!
270 if (D->getType() == Type::VoidTy || // Ignore void type nodes
271 (IgnoreNamedNodes && // Ignore named and constants
272 (D->hasName() || isa<Constant>(D)) && !isa<Type>(D))) {
273 SC_DEBUG("ignored value " << *D << "\n");
274 return -1; // We do need types unconditionally though
277 // If it's a type, make sure that all subtypes of the type are included...
278 if (const Type *TheTy = dyn_cast<Type>(D)) {
280 // Insert the current type before any subtypes. This is important because
281 // recursive types elements are inserted in a bottom up order. Changing
282 // this here can break things. For example:
284 // global { \2 * } { { \2 }* null }
286 int ResultSlot = doInsertValue(TheTy);
287 SC_DEBUG(" Inserted type: " << TheTy->getDescription() << " slot=" <<
290 // Loop over any contained types in the definition... in reverse depth
293 std::vector<const Type*> DfsOrder;
294 for (df_iterator<const Type*> I = df_begin(TheTy), E = df_end(TheTy);
297 // If we haven't seen this sub type before, add it to our type table!
298 DfsOrder.push_back(*I);
302 for (std::vector<const Type*>::const_reverse_iterator
303 I = DfsOrder.rbegin(), E = DfsOrder.rend(); I != E; ++I) {
304 const Type *SubTy = *I;
305 if (getSlot(SubTy) == -1) {
306 SC_DEBUG(" Inserting subtype: " << SubTy->getDescription() << "\n");
307 int Slot = doInsertValue(SubTy);
308 SC_DEBUG(" Inserted subtype: " << SubTy->getDescription() <<
309 " slot=" << Slot << "\n");
315 // Okay, everything is happy, actually insert the silly value now...
316 return doInsertValue(D);
320 // doInsertValue - This is a small helper function to be called only
323 int SlotCalculator::doInsertValue(const Value *D) {
324 const Type *Typ = D->getType();
327 // Used for debugging DefSlot=-1 assertion...
328 //if (Typ == Type::TypeTy)
329 // cerr << "Inserting type '" << cast<Type>(D)->getDescription() << "'!\n";
331 if (Typ->isDerivedType()) {
332 int ValSlot = getSlot(Typ);
333 if (ValSlot == -1) { // Have we already entered this type?
334 // Nope, this is the first we have seen the type, process it.
335 ValSlot = insertValue(Typ, true);
336 assert(ValSlot != -1 && "ProcessType returned -1 for a type?");
338 Ty = (unsigned)ValSlot;
340 Ty = Typ->getPrimitiveID();
343 if (Table.size() <= Ty) // Make sure we have the type plane allocated...
344 Table.resize(Ty+1, TypePlane());
346 // If this is the first value to get inserted into the type plane, make sure
347 // to insert the implicit null value...
348 if (Table[Ty].empty() && Ty >= Type::FirstDerivedTyID && !IgnoreNamedNodes) {
349 Value *ZeroInitializer = Constant::getNullValue(Typ);
351 // If we are pushing zeroinit, it will be handled below.
352 if (D != ZeroInitializer) {
353 Table[Ty].push_back(ZeroInitializer);
354 NodeMap[ZeroInitializer] = 0;
358 // Insert node into table and NodeMap...
359 unsigned DestSlot = NodeMap[D] = Table[Ty].size();
360 Table[Ty].push_back(D);
362 SC_DEBUG(" Inserting value [" << Ty << "] = " << D << " slot=" <<
364 // G = Global, C = Constant, T = Type, F = Function, o = other
365 SC_DEBUG((isa<GlobalVariable>(D) ? "G" : (isa<Constant>(D) ? "C" :
366 (isa<Type>(D) ? "T" : (isa<Function>(D) ? "F" : "o")))));
368 return (int)DestSlot;