-//===-- SlotCalculator.cpp - Calculate what slots values land in ------------=//
+//===-- SlotCalculator.cpp - Calculate what slots values land in ----------===//
//
-// This file implements a useful analysis step to figure out what numbered
-// slots values in a program will land in (keeping track of per plane
-// information as required.
+// The LLVM Compiler Infrastructure
//
-// This is used primarily for when writing a file to disk, either in bytecode
-// or source format.
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements a useful analysis step to figure out what numbered slots
+// values in a program will land in (keeping track of per plane information).
+//
+// This is used when writing a file to disk, either in bytecode or assembly.
//
//===----------------------------------------------------------------------===//
-#include "llvm/Analysis/SlotCalculator.h"
-#include "llvm/ConstantPool.h"
-#include "llvm/Method.h"
-#include "llvm/Module.h"
-#include "llvm/BasicBlock.h"
-#include "llvm/ConstPoolVals.h"
-#include "llvm/iOther.h"
+#include "SlotCalculator.h"
+#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/InlineAsm.h"
+#include "llvm/Instructions.h"
+#include "llvm/Module.h"
+#include "llvm/SymbolTable.h"
+#include "llvm/Type.h"
+#include "llvm/Analysis/ConstantsScanner.h"
+#include "llvm/ADT/PostOrderIterator.h"
+#include "llvm/ADT/STLExtras.h"
+#include <algorithm>
+#include <functional>
+using namespace llvm;
+
+#if 0
+#include <iostream>
+#define SC_DEBUG(X) std::cerr << X
+#else
+#define SC_DEBUG(X)
+#endif
-SlotCalculator::SlotCalculator(const Module *M, bool IgnoreNamed) {
- IgnoreNamedNodes = IgnoreNamed;
+SlotCalculator::SlotCalculator(const Module *M ) {
+ ModuleContainsAllFunctionConstants = false;
+ ModuleTypeLevel = 0;
TheModule = M;
// Preload table... Make sure that all of the primitive types are in the table
// and that their Primitive ID is equal to their slot #
//
+ SC_DEBUG("Inserting primitive types:\n");
for (unsigned i = 0; i < Type::FirstDerivedTyID; ++i) {
- assert(Type::getPrimitiveType((Type::PrimitiveID)i));
- insertVal(Type::getPrimitiveType((Type::PrimitiveID)i));
+ assert(Type::getPrimitiveType((Type::TypeID)i));
+ insertType(Type::getPrimitiveType((Type::TypeID)i), true);
}
if (M == 0) return; // Empty table...
-
- bool Result = processModule(M);
- assert(Result == false && "Error in processModule!");
+ processModule();
}
-SlotCalculator::SlotCalculator(const Method *M, bool IgnoreNamed) {
- IgnoreNamedNodes = IgnoreNamed;
+SlotCalculator::SlotCalculator(const Function *M ) {
+ ModuleContainsAllFunctionConstants = false;
TheModule = M ? M->getParent() : 0;
// Preload table... Make sure that all of the primitive types are in the table
// and that their Primitive ID is equal to their slot #
//
+ SC_DEBUG("Inserting primitive types:\n");
for (unsigned i = 0; i < Type::FirstDerivedTyID; ++i) {
- assert(Type::getPrimitiveType((Type::PrimitiveID)i));
- insertVal(Type::getPrimitiveType((Type::PrimitiveID)i));
+ assert(Type::getPrimitiveType((Type::TypeID)i));
+ insertType(Type::getPrimitiveType((Type::TypeID)i), true);
}
if (TheModule == 0) return; // Empty table...
- bool Result = processModule(TheModule);
- assert(Result == false && "Error in processModule!");
+ processModule(); // Process module level stuff
+ incorporateFunction(M); // Start out in incorporated state
+}
- incorporateMethod(M);
+unsigned SlotCalculator::getGlobalSlot(const Value *V) const {
+ assert(!CompactionTable.empty() &&
+ "This method can only be used when compaction is enabled!");
+ std::map<const Value*, unsigned>::const_iterator I = NodeMap.find(V);
+ assert(I != NodeMap.end() && "Didn't find global slot entry!");
+ return I->second;
}
-void SlotCalculator::incorporateMethod(const Method *M) {
- assert(ModuleLevel.size() == 0 && "Module already incorporated!");
+unsigned SlotCalculator::getGlobalSlot(const Type* T) const {
+ std::map<const Type*, unsigned>::const_iterator I = TypeMap.find(T);
+ assert(I != TypeMap.end() && "Didn't find global slot entry!");
+ return I->second;
+}
- // Save the Table state before we process the method...
- for (unsigned i = 0; i < Table.size(); ++i) {
- ModuleLevel.push_back(Table[i].size());
+SlotCalculator::TypePlane &SlotCalculator::getPlane(unsigned Plane) {
+ if (CompactionTable.empty()) { // No compaction table active?
+ // fall out
+ } else if (!CompactionTable[Plane].empty()) { // Compaction table active.
+ assert(Plane < CompactionTable.size());
+ return CompactionTable[Plane];
+ } else {
+ // Final case: compaction table active, but this plane is not
+ // compactified. If the type plane is compactified, unmap back to the
+ // global type plane corresponding to "Plane".
+ if (!CompactionTypes.empty()) {
+ const Type *Ty = CompactionTypes[Plane];
+ TypeMapType::iterator It = TypeMap.find(Ty);
+ assert(It != TypeMap.end() && "Type not in global constant map?");
+ Plane = It->second;
+ }
}
- // Process the method to incorporate its values into our table
- processMethod(M);
+ // Okay we are just returning an entry out of the main Table. Make sure the
+ // plane exists and return it.
+ if (Plane >= Table.size())
+ Table.resize(Plane+1);
+ return Table[Plane];
+}
+
+// processModule - Process all of the module level function declarations and
+// types that are available.
+//
+void SlotCalculator::processModule() {
+ SC_DEBUG("begin processModule!\n");
+
+ // Add all of the global variables to the value table...
+ //
+ for (Module::const_global_iterator I = TheModule->global_begin(),
+ E = TheModule->global_end(); I != E; ++I)
+ getOrCreateSlot(I);
+
+ // Scavenge the types out of the functions, then add the functions themselves
+ // to the value table...
+ //
+ for (Module::const_iterator I = TheModule->begin(), E = TheModule->end();
+ I != E; ++I)
+ getOrCreateSlot(I);
+
+ // Add all of the module level constants used as initializers
+ //
+ for (Module::const_global_iterator I = TheModule->global_begin(),
+ E = TheModule->global_end(); I != E; ++I)
+ if (I->hasInitializer())
+ getOrCreateSlot(I->getInitializer());
+
+ // Now that all global constants have been added, rearrange constant planes
+ // that contain constant strings so that the strings occur at the start of the
+ // plane, not somewhere in the middle.
+ //
+ for (unsigned plane = 0, e = Table.size(); plane != e; ++plane) {
+ if (const ArrayType *AT = dyn_cast<ArrayType>(Types[plane]))
+ if (AT->getElementType() == Type::SByteTy ||
+ AT->getElementType() == Type::UByteTy) {
+ TypePlane &Plane = Table[plane];
+ unsigned FirstNonStringID = 0;
+ for (unsigned i = 0, e = Plane.size(); i != e; ++i)
+ if (isa<ConstantAggregateZero>(Plane[i]) ||
+ (isa<ConstantArray>(Plane[i]) &&
+ cast<ConstantArray>(Plane[i])->isString())) {
+ // Check to see if we have to shuffle this string around. If not,
+ // don't do anything.
+ if (i != FirstNonStringID) {
+ // Swap the plane entries....
+ std::swap(Plane[i], Plane[FirstNonStringID]);
+
+ // Keep the NodeMap up to date.
+ NodeMap[Plane[i]] = i;
+ NodeMap[Plane[FirstNonStringID]] = FirstNonStringID;
+ }
+ ++FirstNonStringID;
+ }
+ }
+ }
+
+ // Scan all of the functions for their constants, which allows us to emit
+ // more compact modules. This is optional, and is just used to compactify
+ // the constants used by different functions together.
+ //
+ // This functionality tends to produce smaller bytecode files. This should
+ // not be used in the future by clients that want to, for example, build and
+ // emit functions on the fly. For now, however, it is unconditionally
+ // enabled.
+ ModuleContainsAllFunctionConstants = true;
+
+ SC_DEBUG("Inserting function constants:\n");
+ for (Module::const_iterator F = TheModule->begin(), E = TheModule->end();
+ F != E; ++F) {
+ for (const_inst_iterator I = inst_begin(F), E = inst_end(F); I != E; ++I) {
+ for (User::const_op_iterator OI = I->op_begin(), E = I->op_end();
+ OI != E; ++OI) {
+ if ((isa<Constant>(*OI) && !isa<GlobalValue>(*OI)) ||
+ isa<InlineAsm>(*OI))
+ getOrCreateSlot(*OI);
+ }
+ getOrCreateSlot(I->getType());
+ }
+ processSymbolTableConstants(&F->getSymbolTable());
+ }
+
+ // Insert constants that are named at module level into the slot pool so that
+ // the module symbol table can refer to them...
+ SC_DEBUG("Inserting SymbolTable values:\n");
+ processSymbolTable(&TheModule->getSymbolTable());
+
+ // Now that we have collected together all of the information relevant to the
+ // module, compactify the type table if it is particularly big and outputting
+ // a bytecode file. The basic problem we run into is that some programs have
+ // a large number of types, which causes the type field to overflow its size,
+ // which causes instructions to explode in size (particularly call
+ // instructions). To avoid this behavior, we "sort" the type table so that
+ // all non-value types are pushed to the end of the type table, giving nice
+ // low numbers to the types that can be used by instructions, thus reducing
+ // the amount of explodage we suffer.
+ if (Types.size() >= 64) {
+ unsigned FirstNonValueTypeID = 0;
+ for (unsigned i = 0, e = Types.size(); i != e; ++i)
+ if (Types[i]->isFirstClassType() || Types[i]->isPrimitiveType()) {
+ // Check to see if we have to shuffle this type around. If not, don't
+ // do anything.
+ if (i != FirstNonValueTypeID) {
+ // Swap the type ID's.
+ std::swap(Types[i], Types[FirstNonValueTypeID]);
+
+ // Keep the TypeMap up to date.
+ TypeMap[Types[i]] = i;
+ TypeMap[Types[FirstNonValueTypeID]] = FirstNonValueTypeID;
+
+ // When we move a type, make sure to move its value plane as needed.
+ if (Table.size() > FirstNonValueTypeID) {
+ if (Table.size() <= i) Table.resize(i+1);
+ std::swap(Table[i], Table[FirstNonValueTypeID]);
+ }
+ }
+ ++FirstNonValueTypeID;
+ }
+ }
+
+ SC_DEBUG("end processModule!\n");
+}
+
+// processSymbolTable - Insert all of the values in the specified symbol table
+// into the values table...
+//
+void SlotCalculator::processSymbolTable(const SymbolTable *ST) {
+ // Do the types first.
+ for (SymbolTable::type_const_iterator TI = ST->type_begin(),
+ TE = ST->type_end(); TI != TE; ++TI )
+ getOrCreateSlot(TI->second);
+
+ // Now do the values.
+ for (SymbolTable::plane_const_iterator PI = ST->plane_begin(),
+ PE = ST->plane_end(); PI != PE; ++PI)
+ for (SymbolTable::value_const_iterator VI = PI->second.begin(),
+ VE = PI->second.end(); VI != VE; ++VI)
+ getOrCreateSlot(VI->second);
}
-void SlotCalculator::purgeMethod() {
- assert(ModuleLevel.size() != 0 && "Module not incorporated!");
+void SlotCalculator::processSymbolTableConstants(const SymbolTable *ST) {
+ // Do the types first
+ for (SymbolTable::type_const_iterator TI = ST->type_begin(),
+ TE = ST->type_end(); TI != TE; ++TI )
+ getOrCreateSlot(TI->second);
+
+ // Now do the constant values in all planes
+ for (SymbolTable::plane_const_iterator PI = ST->plane_begin(),
+ PE = ST->plane_end(); PI != PE; ++PI)
+ for (SymbolTable::value_const_iterator VI = PI->second.begin(),
+ VE = PI->second.end(); VI != VE; ++VI)
+ if (isa<Constant>(VI->second) &&
+ !isa<GlobalValue>(VI->second))
+ getOrCreateSlot(VI->second);
+}
+
+
+void SlotCalculator::incorporateFunction(const Function *F) {
+ assert((ModuleLevel.size() == 0 ||
+ ModuleTypeLevel == 0) && "Module already incorporated!");
+
+ SC_DEBUG("begin processFunction!\n");
+
+ // If we emitted all of the function constants, build a compaction table.
+ if (ModuleContainsAllFunctionConstants)
+ buildCompactionTable(F);
+
+ // Update the ModuleLevel entries to be accurate.
+ ModuleLevel.resize(getNumPlanes());
+ for (unsigned i = 0, e = getNumPlanes(); i != e; ++i)
+ ModuleLevel[i] = getPlane(i).size();
+ ModuleTypeLevel = Types.size();
+
+ // Iterate over function arguments, adding them to the value table...
+ for(Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I)
+ getOrCreateSlot(I);
+
+ if (!ModuleContainsAllFunctionConstants) {
+ // Iterate over all of the instructions in the function, looking for
+ // constant values that are referenced. Add these to the value pools
+ // before any nonconstant values. This will be turned into the constant
+ // pool for the bytecode writer.
+ //
+
+ // Emit all of the constants that are being used by the instructions in
+ // the function...
+ for (constant_iterator CI = constant_begin(F), CE = constant_end(F);
+ CI != CE; ++CI)
+ getOrCreateSlot(*CI);
+
+ // If there is a symbol table, it is possible that the user has names for
+ // constants that are not being used. In this case, we will have problems
+ // if we don't emit the constants now, because otherwise we will get
+ // symbol table references to constants not in the output. Scan for these
+ // constants now.
+ //
+ processSymbolTableConstants(&F->getSymbolTable());
+ }
+
+ SC_DEBUG("Inserting Instructions:\n");
+
+ // Add all of the instructions to the type planes...
+ for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
+ getOrCreateSlot(BB);
+ for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E; ++I) {
+ getOrCreateSlot(I);
+ }
+ }
+
+ // If we are building a compaction table, prune out planes that do not benefit
+ // from being compactified.
+ if (!CompactionTable.empty())
+ pruneCompactionTable();
+
+ SC_DEBUG("end processFunction!\n");
+}
+
+void SlotCalculator::purgeFunction() {
+ assert((ModuleLevel.size() != 0 ||
+ ModuleTypeLevel != 0) && "Module not incorporated!");
unsigned NumModuleTypes = ModuleLevel.size();
- // First, remove values from existing type planes
- for (unsigned i = 0; i < NumModuleTypes; ++i) {
- unsigned ModuleSize = ModuleLevel[i]; // Size of plane before method came
- while (Table[i].size() != ModuleSize) {
- NodeMap.erase(NodeMap.find(Table[i].back())); // Erase from nodemap
- Table[i].pop_back(); // Shrink plane
+ SC_DEBUG("begin purgeFunction!\n");
+
+ // First, free the compaction map if used.
+ CompactionNodeMap.clear();
+ CompactionTypeMap.clear();
+
+ // Next, remove values from existing type planes
+ for (unsigned i = 0; i != NumModuleTypes; ++i) {
+ // Size of plane before function came
+ unsigned ModuleLev = getModuleLevel(i);
+ assert(int(ModuleLev) >= 0 && "BAD!");
+
+ TypePlane &Plane = getPlane(i);
+
+ assert(ModuleLev <= Plane.size() && "module levels higher than elements?");
+ while (Plane.size() != ModuleLev) {
+ assert(!isa<GlobalValue>(Plane.back()) &&
+ "Functions cannot define globals!");
+ NodeMap.erase(Plane.back()); // Erase from nodemap
+ Plane.pop_back(); // Shrink plane
}
}
// We don't need this state anymore, free it up.
ModuleLevel.clear();
+ ModuleTypeLevel = 0;
- // Next, remove any type planes defined by the method...
- while (NumModuleTypes != Table.size()) {
- TypePlane &Plane = Table.back();
- while (Plane.size()) {
- NodeMap.erase(NodeMap.find(Plane.back())); // Erase from nodemap
- Plane.pop_back(); // Shrink plane
+ // Finally, remove any type planes defined by the function...
+ CompactionTypes.clear();
+ if (!CompactionTable.empty()) {
+ CompactionTable.clear();
+ } else {
+ while (Table.size() > NumModuleTypes) {
+ TypePlane &Plane = Table.back();
+ SC_DEBUG("Removing Plane " << (Table.size()-1) << " of size "
+ << Plane.size() << "\n");
+ while (Plane.size()) {
+ assert(!isa<GlobalValue>(Plane.back()) &&
+ "Functions cannot define globals!");
+ NodeMap.erase(Plane.back()); // Erase from nodemap
+ Plane.pop_back(); // Shrink plane
+ }
+
+ Table.pop_back(); // Nuke the plane, we don't like it.
}
+ }
- Table.pop_back(); // Nuke the plane, we don't like it.
+ SC_DEBUG("end purgeFunction!\n");
+}
+
+static inline bool hasNullValue(const Type *Ty) {
+ return Ty != Type::LabelTy && Ty != Type::VoidTy && !isa<OpaqueType>(Ty);
+}
+
+/// getOrCreateCompactionTableSlot - This method is used to build up the initial
+/// approximation of the compaction table.
+unsigned SlotCalculator::getOrCreateCompactionTableSlot(const Value *V) {
+ std::map<const Value*, unsigned>::iterator I =
+ CompactionNodeMap.lower_bound(V);
+ if (I != CompactionNodeMap.end() && I->first == V)
+ return I->second; // Already exists?
+
+ // Make sure the type is in the table.
+ unsigned Ty;
+ if (!CompactionTypes.empty())
+ Ty = getOrCreateCompactionTableSlot(V->getType());
+ else // If the type plane was decompactified, use the global plane ID
+ Ty = getSlot(V->getType());
+ if (CompactionTable.size() <= Ty)
+ CompactionTable.resize(Ty+1);
+
+ TypePlane &TyPlane = CompactionTable[Ty];
+
+ // Make sure to insert the null entry if the thing we are inserting is not a
+ // null constant.
+ if (TyPlane.empty() && hasNullValue(V->getType())) {
+ Value *ZeroInitializer = Constant::getNullValue(V->getType());
+ if (V != ZeroInitializer) {
+ TyPlane.push_back(ZeroInitializer);
+ CompactionNodeMap[ZeroInitializer] = 0;
+ }
}
+
+ unsigned SlotNo = TyPlane.size();
+ TyPlane.push_back(V);
+ CompactionNodeMap.insert(std::make_pair(V, SlotNo));
+ return SlotNo;
}
-bool SlotCalculator::processConstant(const ConstPoolVal *CPV) {
- //cerr << "Inserting constant: '" << CPV->getStrValue() << endl;
- insertVal(CPV);
- return false;
+/// getOrCreateCompactionTableSlot - This method is used to build up the initial
+/// approximation of the compaction table.
+unsigned SlotCalculator::getOrCreateCompactionTableSlot(const Type *T) {
+ std::map<const Type*, unsigned>::iterator I =
+ CompactionTypeMap.lower_bound(T);
+ if (I != CompactionTypeMap.end() && I->first == T)
+ return I->second; // Already exists?
+
+ unsigned SlotNo = CompactionTypes.size();
+ SC_DEBUG("Inserting Compaction Type #" << SlotNo << ": " << T << "\n");
+ CompactionTypes.push_back(T);
+ CompactionTypeMap.insert(std::make_pair(T, SlotNo));
+ return SlotNo;
}
-// processType - This callback occurs when an derived type is discovered
-// at the class level. This activity occurs when processing a constant pool.
-//
-bool SlotCalculator::processType(const Type *Ty) {
- //cerr << "processType: " << Ty->getName() << endl;
- // TODO: Don't leak memory!!! Free this in the dtor!
- insertVal(new ConstPoolType(Ty));
- return false;
+/// buildCompactionTable - Since all of the function constants and types are
+/// stored in the module-level constant table, we don't need to emit a function
+/// constant table. Also due to this, the indices for various constants and
+/// types might be very large in large programs. In order to avoid blowing up
+/// the size of instructions in the bytecode encoding, we build a compaction
+/// table, which defines a mapping from function-local identifiers to global
+/// identifiers.
+void SlotCalculator::buildCompactionTable(const Function *F) {
+ assert(CompactionNodeMap.empty() && "Compaction table already built!");
+ assert(CompactionTypeMap.empty() && "Compaction types already built!");
+ // First step, insert the primitive types.
+ CompactionTable.resize(Type::LastPrimitiveTyID+1);
+ for (unsigned i = 0; i <= Type::LastPrimitiveTyID; ++i) {
+ const Type *PrimTy = Type::getPrimitiveType((Type::TypeID)i);
+ CompactionTypes.push_back(PrimTy);
+ CompactionTypeMap[PrimTy] = i;
+ }
+
+ // Next, include any types used by function arguments.
+ for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end();
+ I != E; ++I)
+ getOrCreateCompactionTableSlot(I->getType());
+
+ // Next, find all of the types and values that are referred to by the
+ // instructions in the function.
+ for (const_inst_iterator I = inst_begin(F), E = inst_end(F); I != E; ++I) {
+ getOrCreateCompactionTableSlot(I->getType());
+ for (unsigned op = 0, e = I->getNumOperands(); op != e; ++op)
+ if (isa<Constant>(I->getOperand(op)) || isa<InlineAsm>(I->getOperand(op)))
+ getOrCreateCompactionTableSlot(I->getOperand(op));
+ }
+
+ // Do the types in the symbol table
+ const SymbolTable &ST = F->getSymbolTable();
+ for (SymbolTable::type_const_iterator TI = ST.type_begin(),
+ TE = ST.type_end(); TI != TE; ++TI)
+ getOrCreateCompactionTableSlot(TI->second);
+
+ // Now do the constants and global values
+ for (SymbolTable::plane_const_iterator PI = ST.plane_begin(),
+ PE = ST.plane_end(); PI != PE; ++PI)
+ for (SymbolTable::value_const_iterator VI = PI->second.begin(),
+ VE = PI->second.end(); VI != VE; ++VI)
+ if (isa<Constant>(VI->second) && !isa<GlobalValue>(VI->second))
+ getOrCreateCompactionTableSlot(VI->second);
+
+ // Now that we have all of the values in the table, and know what types are
+ // referenced, make sure that there is at least the zero initializer in any
+ // used type plane. Since the type was used, we will be emitting instructions
+ // to the plane even if there are no constants in it.
+ CompactionTable.resize(CompactionTypes.size());
+ for (unsigned i = 0, e = CompactionTable.size(); i != e; ++i)
+ if (CompactionTable[i].empty() && (i != Type::VoidTyID) &&
+ i != Type::LabelTyID) {
+ const Type *Ty = CompactionTypes[i];
+ SC_DEBUG("Getting Null Value #" << i << " for Type " << Ty << "\n");
+ assert(Ty->getTypeID() != Type::VoidTyID);
+ assert(Ty->getTypeID() != Type::LabelTyID);
+ getOrCreateCompactionTableSlot(Constant::getNullValue(Ty));
+ }
+
+ // Okay, now at this point, we have a legal compaction table. Since we want
+ // to emit the smallest possible binaries, do not compactify the type plane if
+ // it will not save us anything. Because we have not yet incorporated the
+ // function body itself yet, we don't know whether or not it's a good idea to
+ // compactify other planes. We will defer this decision until later.
+ TypeList &GlobalTypes = Types;
+
+ // All of the values types will be scrunched to the start of the types plane
+ // of the global table. Figure out just how many there are.
+ assert(!GlobalTypes.empty() && "No global types???");
+ unsigned NumFCTypes = GlobalTypes.size()-1;
+ while (!GlobalTypes[NumFCTypes]->isFirstClassType())
+ --NumFCTypes;
+
+ // If there are fewer that 64 types, no instructions will be exploded due to
+ // the size of the type operands. Thus there is no need to compactify types.
+ // Also, if the compaction table contains most of the entries in the global
+ // table, there really is no reason to compactify either.
+ if (NumFCTypes < 64) {
+ // Decompactifying types is tricky, because we have to move type planes all
+ // over the place. At least we don't need to worry about updating the
+ // CompactionNodeMap for non-types though.
+ std::vector<TypePlane> TmpCompactionTable;
+ std::swap(CompactionTable, TmpCompactionTable);
+ TypeList TmpTypes;
+ std::swap(TmpTypes, CompactionTypes);
+
+ // Move each plane back over to the uncompactified plane
+ while (!TmpTypes.empty()) {
+ const Type *Ty = TmpTypes.back();
+ TmpTypes.pop_back();
+ CompactionTypeMap.erase(Ty); // Decompactify type!
+
+ // Find the global slot number for this type.
+ int TySlot = getSlot(Ty);
+ assert(TySlot != -1 && "Type doesn't exist in global table?");
+
+ // Now we know where to put the compaction table plane.
+ if (CompactionTable.size() <= unsigned(TySlot))
+ CompactionTable.resize(TySlot+1);
+ // Move the plane back into the compaction table.
+ std::swap(CompactionTable[TySlot], TmpCompactionTable[TmpTypes.size()]);
+
+ // And remove the empty plane we just moved in.
+ TmpCompactionTable.pop_back();
+ }
+ }
+}
+
+
+/// pruneCompactionTable - Once the entire function being processed has been
+/// incorporated into the current compaction table, look over the compaction
+/// table and check to see if there are any values whose compaction will not
+/// save us any space in the bytecode file. If compactifying these values
+/// serves no purpose, then we might as well not even emit the compactification
+/// information to the bytecode file, saving a bit more space.
+///
+/// Note that the type plane has already been compactified if possible.
+///
+void SlotCalculator::pruneCompactionTable() {
+ TypeList &TyPlane = CompactionTypes;
+ for (unsigned ctp = 0, e = CompactionTable.size(); ctp != e; ++ctp)
+ if (!CompactionTable[ctp].empty()) {
+ TypePlane &CPlane = CompactionTable[ctp];
+ unsigned GlobalSlot = ctp;
+ if (!TyPlane.empty())
+ GlobalSlot = getGlobalSlot(TyPlane[ctp]);
+
+ if (GlobalSlot >= Table.size())
+ Table.resize(GlobalSlot+1);
+ TypePlane &GPlane = Table[GlobalSlot];
+
+ unsigned ModLevel = getModuleLevel(ctp);
+ unsigned NumFunctionObjs = CPlane.size()-ModLevel;
+
+ // If the maximum index required if all entries in this plane were merged
+ // into the global plane is less than 64, go ahead and eliminate the
+ // plane.
+ bool PrunePlane = GPlane.size() + NumFunctionObjs < 64;
+
+ // If there are no function-local values defined, and the maximum
+ // referenced global entry is less than 64, we don't need to compactify.
+ if (!PrunePlane && NumFunctionObjs == 0) {
+ unsigned MaxIdx = 0;
+ for (unsigned i = 0; i != ModLevel; ++i) {
+ unsigned Idx = NodeMap[CPlane[i]];
+ if (Idx > MaxIdx) MaxIdx = Idx;
+ }
+ PrunePlane = MaxIdx < 64;
+ }
+
+ // Ok, finally, if we decided to prune this plane out of the compaction
+ // table, do so now.
+ if (PrunePlane) {
+ TypePlane OldPlane;
+ std::swap(OldPlane, CPlane);
+
+ // Loop over the function local objects, relocating them to the global
+ // table plane.
+ for (unsigned i = ModLevel, e = OldPlane.size(); i != e; ++i) {
+ const Value *V = OldPlane[i];
+ CompactionNodeMap.erase(V);
+ assert(NodeMap.count(V) == 0 && "Value already in table??");
+ getOrCreateSlot(V);
+ }
+
+ // For compactified global values, just remove them from the compaction
+ // node map.
+ for (unsigned i = 0; i != ModLevel; ++i)
+ CompactionNodeMap.erase(OldPlane[i]);
+
+ // Update the new modulelevel for this plane.
+ assert(ctp < ModuleLevel.size() && "Cannot set modulelevel!");
+ ModuleLevel[ctp] = GPlane.size()-NumFunctionObjs;
+ assert((int)ModuleLevel[ctp] >= 0 && "Bad computation!");
+ }
+ }
}
-bool SlotCalculator::visitMethod(const Method *M) {
- //cerr << "visitMethod: '" << M->getType()->getName() << "'\n";
- insertVal(M);
- return false;
+/// Determine if the compaction table is actually empty. Because the
+/// compaction table always includes the primitive type planes, we
+/// can't just check getCompactionTable().size() because it will never
+/// be zero. Furthermore, the ModuleLevel factors into whether a given
+/// plane is empty or not. This function does the necessary computation
+/// to determine if its actually empty.
+bool SlotCalculator::CompactionTableIsEmpty() const {
+ // Check a degenerate case, just in case.
+ if (CompactionTable.size() == 0) return true;
+
+ // Check each plane
+ for (unsigned i = 0, e = CompactionTable.size(); i < e; ++i) {
+ // If the plane is not empty
+ if (!CompactionTable[i].empty()) {
+ // If the module level is non-zero then at least the
+ // first element of the plane is valid and therefore not empty.
+ unsigned End = getModuleLevel(i);
+ if (End != 0)
+ return false;
+ }
+ }
+ // All the compaction table planes are empty so the table is
+ // considered empty too.
+ return true;
}
-bool SlotCalculator::processMethodArgument(const MethodArgument *MA) {
- insertVal(MA);
- return false;
+int SlotCalculator::getSlot(const Value *V) const {
+ // If there is a CompactionTable active...
+ if (!CompactionNodeMap.empty()) {
+ std::map<const Value*, unsigned>::const_iterator I =
+ CompactionNodeMap.find(V);
+ if (I != CompactionNodeMap.end())
+ return (int)I->second;
+ // Otherwise, if it's not in the compaction table, it must be in a
+ // non-compactified plane.
+ }
+
+ std::map<const Value*, unsigned>::const_iterator I = NodeMap.find(V);
+ if (I != NodeMap.end())
+ return (int)I->second;
+
+ return -1;
+}
+
+int SlotCalculator::getSlot(const Type*T) const {
+ // If there is a CompactionTable active...
+ if (!CompactionTypeMap.empty()) {
+ std::map<const Type*, unsigned>::const_iterator I =
+ CompactionTypeMap.find(T);
+ if (I != CompactionTypeMap.end())
+ return (int)I->second;
+ // Otherwise, if it's not in the compaction table, it must be in a
+ // non-compactified plane.
+ }
+
+ std::map<const Type*, unsigned>::const_iterator I = TypeMap.find(T);
+ if (I != TypeMap.end())
+ return (int)I->second;
+
+ return -1;
}
-bool SlotCalculator::processBasicBlock(const BasicBlock *BB) {
- insertVal(BB);
- ModuleAnalyzer::processBasicBlock(BB); // Lets visit the instructions too!
- return false;
+int SlotCalculator::getOrCreateSlot(const Value *V) {
+ if (V->getType() == Type::VoidTy) return -1;
+
+ int SlotNo = getSlot(V); // Check to see if it's already in!
+ if (SlotNo != -1) return SlotNo;
+
+ if (const GlobalValue *GV = dyn_cast<GlobalValue>(V))
+ assert(GV->getParent() != 0 && "Global not embedded into a module!");
+
+ if (!isa<GlobalValue>(V)) // Initializers for globals are handled explicitly
+ if (const Constant *C = dyn_cast<Constant>(V)) {
+ assert(CompactionNodeMap.empty() &&
+ "All needed constants should be in the compaction map already!");
+
+ // Do not index the characters that make up constant strings. We emit
+ // constant strings as special entities that don't require their
+ // individual characters to be emitted.
+ if (!isa<ConstantArray>(C) || !cast<ConstantArray>(C)->isString()) {
+ // This makes sure that if a constant has uses (for example an array of
+ // const ints), that they are inserted also.
+ //
+ for (User::const_op_iterator I = C->op_begin(), E = C->op_end();
+ I != E; ++I)
+ getOrCreateSlot(*I);
+ } else {
+ assert(ModuleLevel.empty() &&
+ "How can a constant string be directly accessed in a function?");
+ // Otherwise, if we are emitting a bytecode file and this IS a string,
+ // remember it.
+ if (!C->isNullValue())
+ ConstantStrings.push_back(cast<ConstantArray>(C));
+ }
+ }
+
+ return insertValue(V);
}
-bool SlotCalculator::processInstruction(const Instruction *I) {
- insertVal(I);
- return false;
+int SlotCalculator::getOrCreateSlot(const Type* T) {
+ int SlotNo = getSlot(T); // Check to see if it's already in!
+ if (SlotNo != -1) return SlotNo;
+ return insertType(T);
}
-int SlotCalculator::getValSlot(const Value *D) const {
- map<const Value*, unsigned>::const_iterator I = NodeMap.find(D);
- if (I == NodeMap.end()) return -1;
-
- return (int)I->second;
+int SlotCalculator::insertValue(const Value *D, bool dontIgnore) {
+ assert(D && "Can't insert a null value!");
+ assert(getSlot(D) == -1 && "Value is already in the table!");
+
+ // If we are building a compaction map, and if this plane is being compacted,
+ // insert the value into the compaction map, not into the global map.
+ if (!CompactionNodeMap.empty()) {
+ if (D->getType() == Type::VoidTy) return -1; // Do not insert void values
+ assert(!isa<Constant>(D) &&
+ "Types, constants, and globals should be in global table!");
+
+ int Plane = getSlot(D->getType());
+ assert(Plane != -1 && CompactionTable.size() > (unsigned)Plane &&
+ "Didn't find value type!");
+ if (!CompactionTable[Plane].empty())
+ return getOrCreateCompactionTableSlot(D);
+ }
+
+ // If this node does not contribute to a plane, or if the node has a
+ // name and we don't want names, then ignore the silly node... Note that types
+ // do need slot numbers so that we can keep track of where other values land.
+ //
+ if (!dontIgnore) // Don't ignore nonignorables!
+ if (D->getType() == Type::VoidTy ) { // Ignore void type nodes
+ SC_DEBUG("ignored value " << *D << "\n");
+ return -1; // We do need types unconditionally though
+ }
+
+ // Okay, everything is happy, actually insert the silly value now...
+ return doInsertValue(D);
}
-void SlotCalculator::insertVal(const Value *D) {
- if (D == 0) return;
+int SlotCalculator::insertType(const Type *Ty, bool dontIgnore) {
+ assert(Ty && "Can't insert a null type!");
+ assert(getSlot(Ty) == -1 && "Type is already in the table!");
- // If this node does not contribute to a plane, or if the node has a
- // name and we don't want names, then ignore the silly node...
+ // If we are building a compaction map, and if this plane is being compacted,
+ // insert the value into the compaction map, not into the global map.
+ if (!CompactionTypeMap.empty()) {
+ getOrCreateCompactionTableSlot(Ty);
+ }
+
+ // Insert the current type before any subtypes. This is important because
+ // recursive types elements are inserted in a bottom up order. Changing
+ // this here can break things. For example:
+ //
+ // global { \2 * } { { \2 }* null }
//
- if (D->getType() == Type::VoidTy || (IgnoreNamedNodes && D->hasName()))
- return;
+ int ResultSlot = doInsertType(Ty);
+ SC_DEBUG(" Inserted type: " << Ty->getDescription() << " slot=" <<
+ ResultSlot << "\n");
+
+ // Loop over any contained types in the definition... in post
+ // order.
+ for (po_iterator<const Type*> I = po_begin(Ty), E = po_end(Ty);
+ I != E; ++I) {
+ if (*I != Ty) {
+ const Type *SubTy = *I;
+ // If we haven't seen this sub type before, add it to our type table!
+ if (getSlot(SubTy) == -1) {
+ SC_DEBUG(" Inserting subtype: " << SubTy->getDescription() << "\n");
+ doInsertType(SubTy);
+ SC_DEBUG(" Inserted subtype: " << SubTy->getDescription() << "\n");
+ }
+ }
+ }
+ return ResultSlot;
+}
+// doInsertValue - This is a small helper function to be called only
+// be insertValue.
+//
+int SlotCalculator::doInsertValue(const Value *D) {
const Type *Typ = D->getType();
- unsigned Ty = Typ->getPrimitiveID();
+ unsigned Ty;
+
+ // Used for debugging DefSlot=-1 assertion...
+ //if (Typ == Type::TypeTy)
+ // cerr << "Inserting type '" << cast<Type>(D)->getDescription() << "'!\n";
+
if (Typ->isDerivedType()) {
- int DefSlot = getValSlot(Typ);
- if (DefSlot == -1) { // Have we already entered this type?
- // This can happen if a type is first seen in an instruction. For
- // example, if you say 'malloc uint', this defines a type 'uint*' that
- // may be undefined at this point.
- //
- cerr << "SHOULDNT HAPPEN Adding Type ba: " << Typ->getName() << endl;
- assert(0 && "SHouldn't this be taken care of by processType!?!?!");
- // Nope... add this to the Type plane now!
- insertVal(Typ);
-
- DefSlot = getValSlot(Typ);
- assert(DefSlot >= 0 && "Type didn't get inserted correctly!");
+ int ValSlot;
+ if (CompactionTable.empty())
+ ValSlot = getSlot(Typ);
+ else
+ ValSlot = getGlobalSlot(Typ);
+ if (ValSlot == -1) { // Have we already entered this type?
+ // Nope, this is the first we have seen the type, process it.
+ ValSlot = insertType(Typ, true);
+ assert(ValSlot != -1 && "ProcessType returned -1 for a type?");
}
- Ty = (unsigned)DefSlot;
+ Ty = (unsigned)ValSlot;
+ } else {
+ Ty = Typ->getTypeID();
}
-
+
if (Table.size() <= Ty) // Make sure we have the type plane allocated...
Table.resize(Ty+1, TypePlane());
-
- // Insert node into table and NodeMap...
- NodeMap[D] = Table[Ty].size();
-
- if (Typ == Type::TypeTy && // If it's a type constant, add the Type also
- D->getValueType() != Value::TypeVal) {
- assert(D->getValueType() == Value::ConstantVal &&
- "All Type instances should be constant types!");
-
- const ConstPoolType *CPT = (const ConstPoolType*)D;
- int Slot = getValSlot(CPT->getValue());
- if (Slot == -1) {
- // Only add if it's not already here!
- NodeMap[CPT->getValue()] = Table[Ty].size();
- } else if (!CPT->hasName()) { // If the type has no name...
- NodeMap[D] = (unsigned)Slot; // Don't readd type, merge.
- return;
+
+ // If this is the first value to get inserted into the type plane, make sure
+ // to insert the implicit null value...
+ if (Table[Ty].empty() && hasNullValue(Typ)) {
+ Value *ZeroInitializer = Constant::getNullValue(Typ);
+
+ // If we are pushing zeroinit, it will be handled below.
+ if (D != ZeroInitializer) {
+ Table[Ty].push_back(ZeroInitializer);
+ NodeMap[ZeroInitializer] = 0;
}
}
+
+ // Insert node into table and NodeMap...
+ unsigned DestSlot = NodeMap[D] = Table[Ty].size();
Table[Ty].push_back(D);
+
+ SC_DEBUG(" Inserting value [" << Ty << "] = " << D << " slot=" <<
+ DestSlot << " [");
+ // G = Global, C = Constant, T = Type, F = Function, o = other
+ SC_DEBUG((isa<GlobalVariable>(D) ? "G" : (isa<Constant>(D) ? "C" :
+ (isa<Function>(D) ? "F" : "o"))));
+ SC_DEBUG("]\n");
+ return (int)DestSlot;
}
+
+// doInsertType - This is a small helper function to be called only
+// be insertType.
+//
+int SlotCalculator::doInsertType(const Type *Ty) {
+
+ // Insert node into table and NodeMap...
+ unsigned DestSlot = TypeMap[Ty] = Types.size();
+ Types.push_back(Ty);
+
+ SC_DEBUG(" Inserting type [" << DestSlot << "] = " << Ty << "\n" );
+ return (int)DestSlot;
+}
+