bool AliasSet::aliasesUnknownInst(const Instruction *Inst,
AliasAnalysis &AA) const {
if (AliasAny)
return true;
assert(Inst->mayReadOrWriteMemory() &&
"Instruction must either read or write memory.");
for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i) {
if (auto *UnknownInst = getUnknownInst(i)) {
const auto *C1 = dyn_cast<CallBase>(UnknownInst);
const auto *C2 = dyn_cast<CallBase>(Inst);
if (!C1 || !C2 || isModOrRefSet(AA.getModRefInfo(C1, C2)) ||
isModOrRefSet(AA.getModRefInfo(C2, C1)))
return true;
}
}
for (iterator I = begin(), E = end(); I != E; ++I)
if (isModOrRefSet(AA.getModRefInfo(
Inst, MemoryLocation(I.getPointer(), I.getSize(), I.getAAInfo()))))
return true;
return false;
}
static bool isSafeToMove(Instruction *Inst, AliasAnalysis &AA,
SmallPtrSetImpl<Instruction *> &Stores) {
if (Inst->mayWriteToMemory()) {
Stores.insert(Inst);
return false;
}
if (LoadInst *L = dyn_cast<LoadInst>(Inst)) {
MemoryLocation Loc = MemoryLocation::get(L);
for (Instruction *S : Stores)
if (isModSet(AA.getModRefInfo(S, Loc)))
return false;
}
if (Inst->isTerminator() || isa<PHINode>(Inst) || Inst->isEHPad() ||
Inst->mayThrow())
return false;
if (auto *Call = dyn_cast<CallBase>(Inst)) {
// Convergent operations cannot be made control-dependent on additional
// values.
if (Call->hasFnAttr(Attribute::Convergent))
return false;
for (Instruction *S : Stores)
if (isModSet(AA.getModRefInfo(S, Call)))
return false;
}
return true;
}
/// aliasesPointer - Return true if the specified pointer "may" (or must)
/// alias one of the members in the set.
///
bool AliasSet::aliasesPointer(const Value *Ptr, uint64_t Size,
const MDNode *TBAAInfo,
AliasAnalysis &AA) const {
if (AliasTy == MustAlias) {
assert(UnknownInsts.empty() && "Illegal must alias set!");
// If this is a set of MustAliases, only check to see if the pointer aliases
// SOME value in the set.
PointerRec *SomePtr = getSomePointer();
assert(SomePtr && "Empty must-alias set??");
return AA.alias(AliasAnalysis::Location(SomePtr->getValue(),
SomePtr->getSize(),
SomePtr->getTBAAInfo()),
AliasAnalysis::Location(Ptr, Size, TBAAInfo));
}
// If this is a may-alias set, we have to check all of the pointers in the set
// to be sure it doesn't alias the set...
for (iterator I = begin(), E = end(); I != E; ++I)
if (AA.alias(AliasAnalysis::Location(Ptr, Size, TBAAInfo),
AliasAnalysis::Location(I.getPointer(), I.getSize(),
I.getTBAAInfo())))
return true;
// Check the unknown instructions...
if (!UnknownInsts.empty()) {
for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i)
if (AA.getModRefInfo(UnknownInsts[i],
AliasAnalysis::Location(Ptr, Size, TBAAInfo)) !=
AliasAnalysis::NoModRef)
return true;
}
return false;
}
/// aliasesPointer - Return true if the specified pointer "may" (or must)
/// alias one of the members in the set.
///
bool AliasSet::aliasesPointer(const Value *Ptr, unsigned Size,
AliasAnalysis &AA) const {
if (AliasTy == MustAlias) {
assert(CallSites.empty() && "Illegal must alias set!");
// If this is a set of MustAliases, only check to see if the pointer aliases
// SOME value in the set...
HashNodePair *SomePtr = getSomePointer();
assert(SomePtr && "Empty must-alias set??");
return AA.alias(SomePtr->first, SomePtr->second.getSize(), Ptr, Size);
}
// If this is a may-alias set, we have to check all of the pointers in the set
// to be sure it doesn't alias the set...
for (iterator I = begin(), E = end(); I != E; ++I)
if (AA.alias(Ptr, Size, I.getPointer(), I.getSize()))
return true;
// Check the call sites list and invoke list...
if (!CallSites.empty()) {
if (AA.hasNoModRefInfoForCalls())
return true;
for (unsigned i = 0, e = CallSites.size(); i != e; ++i)
if (AA.getModRefInfo(CallSites[i], const_cast<Value*>(Ptr), Size)
!= AliasAnalysis::NoModRef)
return true;
}
return false;
}
bool AliasSet::aliasesCallSite(CallSite CS, AliasAnalysis &AA) const {
if (AA.doesNotAccessMemory(CS))
return false;
for (unsigned i = 0, e = CallSites.size(); i != e; ++i) {
if (AA.getModRefInfo(getCallSite(i), CS) != AliasAnalysis::NoModRef ||
AA.getModRefInfo(CS, getCallSite(i)) != AliasAnalysis::NoModRef)
return true;
}
for (iterator I = begin(), E = end(); I != E; ++I)
if (AA.getModRefInfo(CS, I.getPointer(), I.getSize()) !=
AliasAnalysis::NoModRef)
return true;
return false;
}
bool AliasSet::aliasesUnknownInst(const Instruction *Inst,
AliasAnalysis &AA) const {
if (!Inst->mayReadOrWriteMemory())
return false;
for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i) {
ImmutableCallSite C1(getUnknownInst(i)), C2(Inst);
if (!C1 || !C2 || AA.getModRefInfo(C1, C2) != MRI_NoModRef ||
AA.getModRefInfo(C2, C1) != MRI_NoModRef)
return true;
}
for (iterator I = begin(), E = end(); I != E; ++I)
if (AA.getModRefInfo(Inst, MemoryLocation(I.getPointer(), I.getSize(),
I.getAAInfo())) != MRI_NoModRef)
return true;
return false;
}
bool AliasSet::aliasesUnknownInst(Instruction *Inst, AliasAnalysis &AA) const {
if (!Inst->mayReadOrWriteMemory())
return false;
for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i) {
CallSite C1 = getUnknownInst(i), C2 = Inst;
if (!C1 || !C2 ||
AA.getModRefInfo(C1, C2) != AliasAnalysis::NoModRef ||
AA.getModRefInfo(C2, C1) != AliasAnalysis::NoModRef)
return true;
}
for (iterator I = begin(), E = end(); I != E; ++I)
if (AA.getModRefInfo(Inst, I.getPointer(), I.getSize()) !=
AliasAnalysis::NoModRef)
return true;
return false;
}
bool AliasSet::aliasesCallSite(CallSite CS, AliasAnalysis &AA) const {
if (Function *F = CS.getCalledFunction())
if (AA.doesNotAccessMemory(F))
return false;
if (AA.hasNoModRefInfoForCalls())
return true;
for (unsigned i = 0, e = CallSites.size(); i != e; ++i)
if (AA.getModRefInfo(CallSites[i], CS) != AliasAnalysis::NoModRef ||
AA.getModRefInfo(CS, CallSites[i]) != AliasAnalysis::NoModRef)
return true;
for (iterator I = begin(), E = end(); I != E; ++I)
if (AA.getModRefInfo(CS, I.getPointer(), I.getSize()) !=
AliasAnalysis::NoModRef)
return true;
return false;
}
/// aliasesPointer - If the specified pointer "may" (or must) alias one of the
/// members in the set return the appropriate AliasResult. Otherwise return
/// NoAlias.
///
AliasResult AliasSet::aliasesPointer(const Value *Ptr, LocationSize Size,
const AAMDNodes &AAInfo,
AliasAnalysis &AA) const {
if (AliasAny)
return MayAlias;
if (Alias == SetMustAlias) {
assert(UnknownInsts.empty() && "Illegal must alias set!");
// If this is a set of MustAliases, only check to see if the pointer aliases
// SOME value in the set.
PointerRec *SomePtr = getSomePointer();
assert(SomePtr && "Empty must-alias set??");
return AA.alias(MemoryLocation(SomePtr->getValue(), SomePtr->getSize(),
SomePtr->getAAInfo()),
MemoryLocation(Ptr, Size, AAInfo));
}
// If this is a may-alias set, we have to check all of the pointers in the set
// to be sure it doesn't alias the set...
for (iterator I = begin(), E = end(); I != E; ++I)
if (AliasResult AR = AA.alias(
MemoryLocation(Ptr, Size, AAInfo),
MemoryLocation(I.getPointer(), I.getSize(), I.getAAInfo())))
return AR;
// Check the unknown instructions...
if (!UnknownInsts.empty()) {
for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i)
if (auto *Inst = getUnknownInst(i))
if (isModOrRefSet(
AA.getModRefInfo(Inst, MemoryLocation(Ptr, Size, AAInfo))))
return MayAlias;
}
return NoAlias;
}
