llvm-6502/lib/VMCore/Value.cpp

160 lines
4.9 KiB
C++
Raw Normal View History

//===-- Value.cpp - Implement the Value class -----------------------------===//
//
// This file implements the Value, User, and SymTabValue classes.
//
//===----------------------------------------------------------------------===//
#include "llvm/ValueHolderImpl.h"
#include "llvm/InstrTypes.h"
#include "llvm/SymbolTable.h"
#include "llvm/SymTabValue.h"
#include "llvm/Type.h"
#ifndef NDEBUG // Only in -g mode...
#include "llvm/Assembly/Writer.h"
#endif
#include <algorithm>
//===----------------------------------------------------------------------===//
// Value Class
//===----------------------------------------------------------------------===//
static inline const Type *checkType(const Type *Ty) {
assert(Ty && "Value defined with a null type: Error!");
return Ty;
}
Value::Value(const Type *ty, ValueTy vty, const string &name = "")
: Name(name), Ty(checkType(ty), this) {
VTy = vty;
}
Value::~Value() {
#ifndef NDEBUG // Only in -g mode...
// Check to make sure that there are no uses of this value that are still
// around when the value is destroyed. If there are, then we have a dangling
// reference and something is wrong. This code is here to print out what is
// still being referenced. The value in question should be printed as
// a <badref>
//
if (Uses.begin() != Uses.end()) {
cerr << "While deleting: " << this;
for (use_const_iterator I = Uses.begin(); I != Uses.end(); ++I)
cerr << "Use still stuck around after Def is destroyed:" << *I << endl;
}
#endif
assert(Uses.begin() == Uses.end());
}
void Value::replaceAllUsesWith(Value *D) {
assert(D && "Value::replaceAllUsesWith(<null>) is invalid!");
assert(D != this && "V->replaceAllUsesWith(V) is NOT valid!");
while (!Uses.empty()) {
User *Use = Uses.back();
#ifndef NDEBUG
unsigned NumUses = Uses.size();
#endif
Use->replaceUsesOfWith(this, D);
#ifndef NDEBUG // only in -g mode...
if (Uses.size() == NumUses)
cerr << "Use: " << Use << "replace with: " << D;
#endif
assert(Uses.size() != NumUses && "Didn't remove definition!");
}
}
// refineAbstractType - This function is implemented because we use
// potentially abstract types, and these types may be resolved to more
// concrete types after we are constructed. For the value class, we simply
// change Ty to point to the right type. :)
//
void Value::refineAbstractType(const DerivedType *OldTy, const Type *NewTy) {
assert(Ty.get() == (const Type*)OldTy &&"Can't refine anything but my type!");
Ty = NewTy;
}
void Value::killUse(User *i) {
if (i == 0) return;
use_iterator I = find(Uses.begin(), Uses.end(), i);
assert(I != Uses.end() && "Use not in uses list!!");
Uses.erase(I);
}
User *Value::use_remove(use_iterator &I) {
assert(I != Uses.end() && "Trying to remove the end of the use list!!!");
User *i = *I;
I = Uses.erase(I);
return i;
}
#ifndef NDEBUG // Only in -g mode...
void Value::dump() const {
cerr << this;
}
#endif
//===----------------------------------------------------------------------===//
// User Class
//===----------------------------------------------------------------------===//
User::User(const Type *Ty, ValueTy vty, const string &name)
: Value(Ty, vty, name) {
}
// replaceUsesOfWith - Replaces all references to the "From" definition with
// references to the "To" definition.
//
void User::replaceUsesOfWith(Value *From, Value *To) {
if (From == To) return; // Duh what?
for (unsigned i = 0, E = getNumOperands(); i != E; ++i)
if (getOperand(i) == From) { // Is This operand is pointing to oldval?
// The side effects of this setOperand call include linking to
// "To", adding "this" to the uses list of To, and
// most importantly, removing "this" from the use list of "From".
setOperand(i, To); // Fix it now...
}
}
//===----------------------------------------------------------------------===//
// SymTabValue Class
//===----------------------------------------------------------------------===//
SymTabValue::SymTabValue(Value *p) : ValueParent(p) {
assert(ValueParent && "SymTavValue without parent!?!");
ParentSymTab = SymTab = 0;
}
SymTabValue::~SymTabValue() {
delete SymTab;
}
void SymTabValue::setParentSymTab(SymbolTable *ST) {
ParentSymTab = ST;
if (SymTab)
SymTab->setParentSymTab(ST);
}
SymbolTable *SymTabValue::getSymbolTableSure() {
if (!SymTab) SymTab = new SymbolTable(ParentSymTab);
return SymTab;
}
// hasSymbolTable() - Returns true if there is a symbol table allocated to
// this object AND if there is at least one name in it!
//
bool SymTabValue::hasSymbolTable() const {
if (!SymTab) return false;
for (SymbolTable::const_iterator I = SymTab->begin();
I != SymTab->end(); ++I) {
if (I->second.begin() != I->second.end())
return true; // Found nonempty type plane!
}
return false;
}