Added some experimental optimizations to remove dead values from the

state.

llvm-svn: 46106
This commit is contained in:
Ted Kremenek 2008-01-17 00:52:48 +00:00
parent 1aa1941889
commit e780f408b1
1 changed files with 51 additions and 14 deletions

View File

@ -65,7 +65,7 @@ public:
inline bool operator!=(const DSPtr& X) const { return Raw != X.Raw; }
inline bool operator<(const DSPtr& X) const {
VariantKind k = getKind(), Xk = X.getKind();
return k == Xk ? getPtr() < X.getPtr() : k < Xk;
return k == Xk ? getPtr() < X.getPtr() : ((unsigned) k) < ((unsigned) Xk);
}
};
} // end anonymous namespace
@ -76,7 +76,7 @@ namespace llvm {
return V.getKind() == DSPtr::IsValueDecl;
}
template<> inline bool isa<Stmt,DSPtr>(const DSPtr& V) {
return ((unsigned) V.getKind()) > DSPtr::IsValueDecl;
return ((unsigned) V.getKind()) != DSPtr::IsValueDecl;
}
template<> struct VISIBILITY_HIDDEN cast_retty_impl<ValueDecl,DSPtr> {
typedef const ValueDecl* ret_type;
@ -174,11 +174,12 @@ protected:
NodeSetTy* Nodes;
NodeSetTy* OldNodes;
StateTy CurrentState;
NodeTy* InitialPred;
public:
GRConstants() : Liveness(NULL), Builder(NULL), cfg(NULL),
Nodes(&NodeSetA), OldNodes(&NodeSetB),
CurrentState(StateMgr.GetEmptyMap()) {}
CurrentState(StateMgr.GetEmptyMap()), InitialPred(NULL) {}
~GRConstants() { delete Liveness; }
@ -197,7 +198,9 @@ public:
void ProcessStmt(Stmt* S, NodeBuilder& builder);
void SwitchNodeSets();
void DoStmt(Stmt* S);
StateTy RemoveGrandchildrenMappings(Stmt* S, StateTy M);
StateTy RemoveDescendantMappings(Stmt* S, StateTy M, unsigned Levels=2);
StateTy RemoveSubExprMappings(StateTy M);
void AddBinding(Expr* E, ExprVariantTy V, bool isBlkLvl = false);
void AddBinding(ValueDecl* D, ExprVariantTy V);
@ -224,9 +227,10 @@ void GRConstants::ProcessStmt(Stmt* S, NodeBuilder& builder) {
Builder = &builder;
Nodes->clear();
OldNodes->clear();
NodeTy* N = Builder->getLastNode();
assert (N);
OldNodes->push_back(N);
InitialPred = Builder->getLastNode();
assert (InitialPred);
OldNodes->push_back(InitialPred);
CurrentState = RemoveSubExprMappings(InitialPred->getState());
BlockStmt_Visit(S);
Builder = NULL;
}
@ -276,22 +280,51 @@ void GRConstants::SwitchNodeSets() {
}
GRConstants::StateTy
GRConstants::RemoveGrandchildrenMappings(Stmt* S, GRConstants::StateTy State) {
GRConstants::RemoveSubExprMappings(StateTy M) {
#if 0
return M;
#else
for (StateTy::iterator I = M.begin(), E = M.end();
I!=E && I.getKey().getKind() == DSPtr::IsSubExp; ++I) {
// Note: we can assign a new map to M since the iterators are
// iterating over the tree of the original map (aren't immutable maps
// nice?).
M = StateMgr.Remove(M, I.getKey());
}
return M;
#endif
}
GRConstants::StateTy
GRConstants::RemoveDescendantMappings(Stmt* S, GRConstants::StateTy State,
unsigned Levels) {
#if 1
return State;
#else
typedef Stmt::child_iterator iterator;
for (iterator I=S->child_begin(), E=S->child_end(); I!=E; ++I)
if (Stmt* C = *I)
for (iterator CI=C->child_begin(), CE=C->child_end(); CI!=CE; ++CI) {
if (Stmt* C = *I) {
if (Levels == 1) {
// Observe that this will only remove mappings to non-block level
// expressions. This is valid even if *CI is a block-level expression,
// since it simply won't be in the map in the first place.
// Note: This should also work if 'C' is a block-level expression,
// although ideally we would want to skip processing C's children.
State = StateMgr.Remove(State, DSPtr(*CI,false));
State = StateMgr.Remove(State, DSPtr(C,false));
}
else {
if (ParenExpr* P = dyn_cast<ParenExpr>(C))
State = RemoveDescendantMappings(P, State, Levels);
else
State = RemoveDescendantMappings(C, State, Levels-1);
}
}
return State;
#endif
}
void GRConstants::DoStmt(Stmt* S) {
@ -300,10 +333,14 @@ void GRConstants::DoStmt(Stmt* S) {
for (NodeSetTy::iterator I=OldNodes->begin(), E=OldNodes->end(); I!=E; ++I) {
NodeTy* Pred = *I;
if (Pred != InitialPred)
CurrentState = Pred->getState();
StateTy OldState = CurrentState;
CurrentState = RemoveGrandchildrenMappings(S, CurrentState);
if (Pred != InitialPred)
CurrentState = RemoveDescendantMappings(S, CurrentState);
Visit(S);