/// to make sure that there are no complex uses of V. We permit simple things
/// like dereferencing the pointer, but not storing through the address, unless
/// it is to the specified global.
-static bool ValueIsOnlyUsedLocallyOrStoredToOneGlobal(Instruction *V,
- GlobalVariable *GV,
- SmallPtrSet<PHINode*, 8> &PHIs) {
- for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI != E;++UI){
- Instruction *Inst = cast<Instruction>(*UI);
+static bool ValueIsOnlyUsedLocallyOrStoredToOneGlobal(const Instruction *V,
+ const GlobalVariable *GV,
+ SmallPtrSet<const PHINode*, 8> &PHIs) {
+ for (Value::const_use_iterator UI = V->use_begin(), E = V->use_end();
+ UI != E;++UI){
+ const Instruction *Inst = cast<Instruction>(*UI);
if (isa<LoadInst>(Inst) || isa<CmpInst>(Inst)) {
continue; // Fine, ignore.
}
- if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
+ if (const StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
if (SI->getOperand(0) == V && SI->getOperand(1) != GV)
return false; // Storing the pointer itself... bad.
continue; // Otherwise, storing through it, or storing into GV... fine.
continue;
}
- if (PHINode *PN = dyn_cast<PHINode>(Inst)) {
+ if (const PHINode *PN = dyn_cast<PHINode>(Inst)) {
// PHIs are ok if all uses are ok. Don't infinitely recurse through PHI
// cycles.
if (PHIs.insert(PN))
continue;
}
- if (BitCastInst *BCI = dyn_cast<BitCastInst>(Inst)) {
+ if (const BitCastInst *BCI = dyn_cast<BitCastInst>(Inst)) {
if (!ValueIsOnlyUsedLocallyOrStoredToOneGlobal(BCI, GV, PHIs))
return false;
continue;
// GEP'd. These are all things we could transform to using the global
// for.
{
- SmallPtrSet<PHINode*, 8> PHIs;
+ SmallPtrSet<const PHINode*, 8> PHIs;
if (!ValueIsOnlyUsedLocallyOrStoredToOneGlobal(CI, GV, PHIs))
return false;
}