[llvm-commits] [llvm] r60231 - in /llvm/trunk: include/llvm/Analysis/MemoryDependenceAnalysis.h lib/Analysis/MemoryDependenceAnalysis.cpp lib/Transforms/Scalar/DeadStoreElimination.cpp lib/Transforms/Scalar/GVN.cpp lib/Transforms/Scalar/MemCpyOptimizer.cpp
Chris Lattner
sabre at nondot.org
Fri Nov 28 18:29:28 PST 2008
Author: lattner
Date: Fri Nov 28 20:29:27 2008
New Revision: 60231
URL: http://llvm.org/viewvc/llvm-project?rev=60231&view=rev
Log:
Introduce and use a new MemDepResult class to hold the results of a memdep
query. This makes it crystal clear what cases can escape from MemDep that
the clients have to handle. This also gives the clients a nice simplified
interface to it that is easy to poke at.
This patch also makes DepResultTy and MemoryDependenceAnalysis::DepType
private, yay.
Modified:
llvm/trunk/include/llvm/Analysis/MemoryDependenceAnalysis.h
llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp
llvm/trunk/lib/Transforms/Scalar/DeadStoreElimination.cpp
llvm/trunk/lib/Transforms/Scalar/GVN.cpp
llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp
Modified: llvm/trunk/include/llvm/Analysis/MemoryDependenceAnalysis.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/MemoryDependenceAnalysis.h?rev=60231&r1=60230&r2=60231&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/MemoryDependenceAnalysis.h (original)
+++ llvm/trunk/include/llvm/Analysis/MemoryDependenceAnalysis.h Fri Nov 28 20:29:27 2008
@@ -24,13 +24,62 @@
class FunctionPass;
class Instruction;
class CallSite;
+
+ /// MemDepResult - A memory dependence query can return one of three different
+ /// answers:
+ /// Normal : The query is dependent on a specific instruction.
+ /// NonLocal: The query does not depend on anything inside this block, but
+ /// we haven't scanned beyond the block to find out what.
+ /// None : The query does not depend on anything: we found the entry
+ /// block or the allocation site of the memory.
+ class MemDepResult {
+ enum DepType {
+ Invalid = 0, Normal, NonLocal, None
+ };
+ typedef PointerIntPair<Instruction*, 2, DepType> PairTy;
+ PairTy Value;
+ explicit MemDepResult(PairTy V) : Value(V) {}
+ public:
+ MemDepResult() : Value(0, Invalid) {}
+
+ /// get methods: These are static ctor methods for creating various
+ /// MemDepResult kinds.
+ static MemDepResult get(Instruction *Inst) {
+ return MemDepResult(PairTy(Inst, Normal));
+ }
+ static MemDepResult getNonLocal() {
+ return MemDepResult(PairTy(0, NonLocal));
+ }
+ static MemDepResult getNone() {
+ return MemDepResult(PairTy(0, None));
+ }
+
+ /// isNormal - Return true if this MemDepResult represents a query that is
+ /// a normal instruction dependency.
+ bool isNormal() const { return Value.getInt() == Normal; }
+
+ /// isNonLocal - Return true if this MemDepResult represents an query that
+ /// is transparent to the start of the block, but where a non-local hasn't
+ /// been done.
+ bool isNonLocal() const { return Value.getInt() == NonLocal; }
+
+ /// isNone - Return true if this MemDepResult represents a query that
+ /// doesn't depend on any instruction.
+ bool isNone() const { return Value.getInt() == None; }
+
+ /// getInst() - If this is a normal dependency, return the instruction that
+ /// is depended on. Otherwise, return null.
+ Instruction *getInst() const { return isNormal() ? Value.getPointer() : 0; }
+
+ bool operator==(const MemDepResult &M) { return M.Value == Value; }
+ bool operator!=(const MemDepResult &M) { return M.Value != Value; }
+ };
/// MemoryDependenceAnalysis - This is an analysis that determines, for a
/// given memory operation, what preceding memory operations it depends on.
/// It builds on alias analysis information, and tries to provide a lazy,
/// caching interface to a common kind of alias information query.
class MemoryDependenceAnalysis : public FunctionPass {
- public:
/// DepType - This enum is used to indicate what flavor of dependence this
/// is. If the type is Normal, there is an associated instruction pointer.
enum DepType {
@@ -54,7 +103,7 @@
Dirty
};
typedef PointerIntPair<Instruction*, 2, DepType> DepResultTy;
- private:
+
// A map from instructions to their dependency, with a boolean
// flags for whether this mapping is confirmed or not.
typedef DenseMap<Instruction*,
@@ -62,6 +111,7 @@
LocalDepMapType LocalDeps;
// A map from instructions to their non-local dependencies.
+ // FIXME: DENSEMAP of DENSEMAP not a great idea.
typedef DenseMap<Instruction*,
DenseMap<BasicBlock*, DepResultTy> > nonLocalDepMapType;
nonLocalDepMapType depGraphNonLocal;
@@ -98,14 +148,14 @@
/// getDependency - Return the instruction on which a memory operation
/// depends, starting with start.
- DepResultTy getDependency(Instruction *query, Instruction *start = 0,
- BasicBlock *block = 0);
+ MemDepResult getDependency(Instruction *query, Instruction *start = 0,
+ BasicBlock *block = 0);
/// getNonLocalDependency - Fills the passed-in map with the non-local
/// dependencies of the queries. The map will contain NonLocal for
/// blocks between the query and its dependencies.
void getNonLocalDependency(Instruction* query,
- DenseMap<BasicBlock*, DepResultTy> &resp);
+ DenseMap<BasicBlock*, MemDepResult> &resp);
/// removeInstruction - Remove an instruction from the dependence analysis,
/// updating the dependence of instructions that previously depended on it.
@@ -117,14 +167,33 @@
void dropInstruction(Instruction *InstToDrop);
private:
+ DepResultTy ConvFromResult(MemDepResult R) {
+ if (Instruction *I = R.getInst())
+ return DepResultTy(I, Normal);
+ if (R.isNonLocal())
+ return DepResultTy(0, NonLocal);
+ assert(R.isNone() && "Unknown MemDepResult!");
+ return DepResultTy(0, None);
+ }
+
+ MemDepResult ConvToResult(DepResultTy R) {
+ if (R.getInt() == Normal)
+ return MemDepResult::get(R.getPointer());
+ if (R.getInt() == NonLocal)
+ return MemDepResult::getNonLocal();
+ assert(R.getInt() == None && "Unknown MemDepResult!");
+ return MemDepResult::getNone();
+ }
+
+
/// verifyRemoved - Verify that the specified instruction does not occur
/// in our internal data structures.
void verifyRemoved(Instruction *Inst) const;
- DepResultTy getCallSiteDependency(CallSite C, Instruction* start,
- BasicBlock* block);
+ MemDepResult getCallSiteDependency(CallSite C, Instruction* start,
+ BasicBlock* block);
void nonLocalHelper(Instruction* query, BasicBlock* block,
- DenseMap<BasicBlock*, DepResultTy>& resp);
+ DenseMap<BasicBlock*, DepResultTy> &resp);
};
} // End llvm namespace
Modified: llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp?rev=60231&r1=60230&r2=60231&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp (original)
+++ llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp Fri Nov 28 20:29:27 2008
@@ -87,8 +87,7 @@
/// getCallSiteDependency - Private helper for finding the local dependencies
/// of a call site.
-MemoryDependenceAnalysis::DepResultTy
-MemoryDependenceAnalysis::
+MemDepResult MemoryDependenceAnalysis::
getCallSiteDependency(CallSite C, Instruction *start, BasicBlock *block) {
std::pair<DepResultTy, bool> &cachedResult = LocalDeps[C.getInstruction()];
AliasAnalysis& AA = getAnalysis<AliasAnalysis>();
@@ -140,7 +139,7 @@
cachedResult.second = true;
reverseDep[DepResultTy(QI, Normal)].insert(C.getInstruction());
}
- return DepResultTy(QI, Normal);
+ return MemDepResult::get(QI);
} else {
continue;
}
@@ -153,7 +152,7 @@
cachedResult.second = true;
reverseDep[DepResultTy(QI, Normal)].insert(C.getInstruction());
}
- return DepResultTy(QI, Normal);
+ return MemDepResult::get(QI);
}
}
@@ -161,7 +160,7 @@
cachedResult.first = DepResultTy(0, NonLocal);
cachedResult.second = true;
reverseDep[DepResultTy(0, NonLocal)].insert(C.getInstruction());
- return DepResultTy(0, NonLocal);
+ return MemDepResult::getNonLocal();
}
/// nonLocalHelper - Private helper used to calculate non-local dependencies
@@ -199,11 +198,10 @@
if (BB != block) {
visited.insert(BB);
- DepResultTy localDep = getDependency(query, 0, BB);
- if (localDep.getInt() != NonLocal) {
- resp.insert(std::make_pair(BB, localDep));
+ MemDepResult localDep = getDependency(query, 0, BB);
+ if (!localDep.isNonLocal()) {
+ resp.insert(std::make_pair(BB, ConvFromResult(localDep)));
stack.pop_back();
-
continue;
}
// If we re-encounter the starting block, we still need to search it
@@ -212,12 +210,11 @@
} else if (BB == block) {
visited.insert(BB);
- DepResultTy localDep = getDependency(query, 0, BB);
- if (localDep != DepResultTy(query, Normal))
- resp.insert(std::make_pair(BB, localDep));
+ MemDepResult localDep = getDependency(query, 0, BB);
+ if (localDep.getInst() != query)
+ resp.insert(std::make_pair(BB, ConvFromResult(localDep)));
stack.pop_back();
-
continue;
}
@@ -257,7 +254,7 @@
/// dependencies of the queries. The map will contain NonLocal for
/// blocks between the query and its dependencies.
void MemoryDependenceAnalysis::getNonLocalDependency(Instruction* query,
- DenseMap<BasicBlock*, DepResultTy> &resp) {
+ DenseMap<BasicBlock*, MemDepResult> &resp) {
if (depGraphNonLocal.count(query)) {
DenseMap<BasicBlock*, DepResultTy> &cached = depGraphNonLocal[query];
NumCacheNonlocal++;
@@ -270,44 +267,46 @@
for (SmallVector<BasicBlock*, 4>::iterator I = dirtied.begin(),
E = dirtied.end(); I != E; ++I) {
- DepResultTy localDep = getDependency(query, 0, *I);
- if (localDep.getInt() != NonLocal)
- cached[*I] = localDep;
+ MemDepResult localDep = getDependency(query, 0, *I);
+ if (!localDep.isNonLocal())
+ cached[*I] = ConvFromResult(localDep);
else {
cached.erase(*I);
nonLocalHelper(query, *I, cached);
}
}
- resp = cached;
-
- // Update the reverse non-local dependency cache
- for (DenseMap<BasicBlock*, DepResultTy>::iterator I = resp.begin(),
- E = resp.end(); I != E; ++I)
+ // Update the reverse non-local dependency cache.
+ for (DenseMap<BasicBlock*, DepResultTy>::iterator I = cached.begin(),
+ E = cached.end(); I != E; ++I) {
reverseDepNonLocal[I->second].insert(query);
+ resp[I->first] = ConvToResult(I->second);
+ }
return;
- } else
- NumUncacheNonlocal++;
+ }
- // If not, go ahead and search for non-local deps.
- nonLocalHelper(query, query->getParent(), resp);
+ NumUncacheNonlocal++;
+ // If not, go ahead and search for non-local deps.
+ DenseMap<BasicBlock*, DepResultTy> &cached = depGraphNonLocal[query];
+ nonLocalHelper(query, query->getParent(), cached);
+
// Update the non-local dependency cache
- for (DenseMap<BasicBlock*, DepResultTy>::iterator I = resp.begin(),
- E = resp.end(); I != E; ++I) {
- depGraphNonLocal[query].insert(*I);
+ for (DenseMap<BasicBlock*, DepResultTy>::iterator I = cached.begin(),
+ E = cached.end(); I != E; ++I) {
+ // FIXME: Merge with the code above!
reverseDepNonLocal[I->second].insert(query);
+ resp[I->first] = ConvToResult(I->second);
}
}
/// getDependency - Return the instruction on which a memory operation
/// depends. The local parameter indicates if the query should only
/// evaluate dependencies within the same basic block.
-MemoryDependenceAnalysis::DepResultTy
-MemoryDependenceAnalysis::getDependency(Instruction *query,
- Instruction *start,
- BasicBlock *block) {
+MemDepResult MemoryDependenceAnalysis::getDependency(Instruction *query,
+ Instruction *start,
+ BasicBlock *block) {
// Start looking for dependencies with the queried inst
BasicBlock::iterator QI = query;
@@ -316,7 +315,7 @@
// If we have a _confirmed_ cached entry, return it
if (!block && !start) {
if (cachedResult.second)
- return cachedResult.first;
+ return ConvToResult(cachedResult.first);
else if (cachedResult.first.getInt() == Normal &&
cachedResult.first.getPointer())
// If we have an unconfirmed cached entry, we can start our search from
@@ -355,9 +354,9 @@
} else if (CallSite::get(query).getInstruction() != 0)
return getCallSiteDependency(CallSite::get(query), start, block);
else if (isa<AllocationInst>(query))
- return DepResultTy(0, None);
+ return MemDepResult::getNone();
else
- return DepResultTy(0, None);
+ return MemDepResult::getNone();
BasicBlock::iterator blockBegin = block ? block->begin()
: query->getParent()->begin();
@@ -378,7 +377,7 @@
reverseDep[DepResultTy(S, Normal)].insert(query);
}
- return DepResultTy(S, Normal);
+ return MemDepResult::get(S);
}
pointer = S->getPointerOperand();
@@ -392,7 +391,7 @@
reverseDep[DepResultTy(L, Normal)].insert(query);
}
- return DepResultTy(L, Normal);
+ return MemDepResult::get(L);
}
pointer = L->getPointerOperand();
@@ -427,7 +426,7 @@
cachedResult.second = true;
reverseDep[DepResultTy(QI, Normal)].insert(query);
}
- return DepResultTy(QI, Normal);
+ return MemDepResult::get(QI);
} else {
continue;
}
@@ -450,7 +449,7 @@
reverseDep[DepResultTy(QI, Normal)].insert(query);
}
- return DepResultTy(QI, Normal);
+ return MemDepResult::get(QI);
}
}
}
@@ -462,7 +461,7 @@
reverseDep[DepResultTy(0, NonLocal)].insert(query);
}
- return DepResultTy(0, NonLocal);
+ return MemDepResult::getNonLocal();
}
/// dropInstruction - Remove an instruction from the analysis, making
Modified: llvm/trunk/lib/Transforms/Scalar/DeadStoreElimination.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/DeadStoreElimination.cpp?rev=60231&r1=60230&r2=60231&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/DeadStoreElimination.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/DeadStoreElimination.cpp Fri Nov 28 20:29:27 2008
@@ -47,10 +47,8 @@
return Changed;
}
- typedef MemoryDependenceAnalysis::DepResultTy DepResultTy;
-
bool runOnBasicBlock(BasicBlock &BB);
- bool handleFreeWithNonTrivialDependency(FreeInst *F, DepResultTy Dep);
+ bool handleFreeWithNonTrivialDependency(FreeInst *F, MemDepResult Dep);
bool handleEndBlock(BasicBlock &BB);
bool RemoveUndeadPointers(Value* pointer, uint64_t killPointerSize,
BasicBlock::iterator& BBI,
@@ -110,16 +108,15 @@
// ... to a pointer that has been stored to before...
if (last) {
- DepResultTy dep = MD.getDependency(Inst);
+ MemDepResult dep = MD.getDependency(Inst);
bool deletedStore = false;
// ... and no other memory dependencies are between them....
- while (dep.getInt() == MemoryDependenceAnalysis::Normal &&
- isa<StoreInst>(dep.getPointer())) {
- if (dep.getPointer() != last ||
- TD.getTypeStoreSize(last->getOperand(0)->getType()) >
- TD.getTypeStoreSize(Inst->getOperand(0)->getType())) {
- dep = MD.getDependency(Inst, dep.getPointer());
+ while (StoreInst *DepStore = dyn_cast_or_null<StoreInst>(dep.getInst())) {
+ if (DepStore != last ||
+ TD.getTypeStoreSize(last->getOperand(0)->getType()) >
+ TD.getTypeStoreSize(Inst->getOperand(0)->getType())) {
+ dep = MD.getDependency(Inst, DepStore);
continue;
}
@@ -152,14 +149,12 @@
// loaded from, then the store can be removed;
if (LoadInst* L = dyn_cast<LoadInst>(S->getOperand(0))) {
// FIXME: Don't do dep query if Parents don't match and other stuff!
- DepResultTy dep = MD.getDependency(S);
+ MemDepResult dep = MD.getDependency(S);
DominatorTree& DT = getAnalysis<DominatorTree>();
if (!S->isVolatile() && S->getParent() == L->getParent() &&
S->getPointerOperand() == L->getPointerOperand() &&
- (dep.getInt() == MemoryDependenceAnalysis::None ||
- dep.getInt() == MemoryDependenceAnalysis::NonLocal ||
- DT.dominates(dep.getPointer(), L))) {
+ (!dep.isNormal() || DT.dominates(dep.getInst(), L))) {
DeleteDeadInstruction(S);
if (!isa<TerminatorInst>(BB.begin()))
@@ -185,15 +180,11 @@
/// handleFreeWithNonTrivialDependency - Handle frees of entire structures whose
/// dependency is a store to a field of that structure.
-bool DSE::handleFreeWithNonTrivialDependency(FreeInst* F, DepResultTy dep) {
+bool DSE::handleFreeWithNonTrivialDependency(FreeInst* F, MemDepResult dep) {
TargetData &TD = getAnalysis<TargetData>();
AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
- if (dep.getInt() == MemoryDependenceAnalysis::None ||
- dep.getInt() == MemoryDependenceAnalysis::NonLocal)
- return false;
-
- StoreInst* dependency = dyn_cast<StoreInst>(dep.getPointer());
+ StoreInst* dependency = dyn_cast_or_null<StoreInst>(dep.getInst());
if (!dependency)
return false;
else if (dependency->isVolatile())
Modified: llvm/trunk/lib/Transforms/Scalar/GVN.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/GVN.cpp?rev=60231&r1=60230&r2=60231&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/GVN.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/GVN.cpp Fri Nov 28 20:29:27 2008
@@ -456,19 +456,19 @@
return nextValueNumber++;
}
- MemoryDependenceAnalysis::DepResultTy local_dep = MD->getDependency(C);
+ MemDepResult local_dep = MD->getDependency(C);
- if (local_dep.getInt() == MemoryDependenceAnalysis::None) {
+ if (local_dep.isNone()) {
valueNumbering.insert(std::make_pair(V, nextValueNumber));
return nextValueNumber++;
- } else if (local_dep.getInt() != MemoryDependenceAnalysis::NonLocal) {
+ } else if (Instruction *LocalDepInst = local_dep.getInst()) {
// FIXME: INDENT PROPERLY!
- if (!isa<CallInst>(local_dep.getPointer())) {
+ if (!isa<CallInst>(LocalDepInst)) {
valueNumbering.insert(std::make_pair(V, nextValueNumber));
return nextValueNumber++;
}
- CallInst* local_cdep = cast<CallInst>(local_dep.getPointer());
+ CallInst* local_cdep = cast<CallInst>(LocalDepInst);
// FIXME: INDENT PROPERLY.
if (local_cdep->getCalledFunction() != C->getCalledFunction() ||
@@ -495,20 +495,21 @@
}
- DenseMap<BasicBlock*, MemoryDependenceAnalysis::DepResultTy> deps;
+ DenseMap<BasicBlock*, MemDepResult> deps;
MD->getNonLocalDependency(C, deps);
CallInst* cdep = 0;
- for (DenseMap<BasicBlock*, MemoryDependenceAnalysis::DepResultTy>
+ for (DenseMap<BasicBlock*, MemDepResult>
::iterator I = deps.begin(), E = deps.end(); I != E; ++I) {
- if (I->second.getInt() == MemoryDependenceAnalysis::None) {
+ if (I->second.isNone()) {
valueNumbering.insert(std::make_pair(V, nextValueNumber));
return nextValueNumber++;
- } else if (I->second.getInt() != MemoryDependenceAnalysis::NonLocal) {
+ } else if (Instruction *NonLocalDepInst = I->second.getInst()) {
// FIXME: INDENT PROPERLY
+ // FIXME: All duplicated with non-local case.
if (DT->properlyDominates(I->first, C->getParent())) {
- if (CallInst* CD = dyn_cast<CallInst>(I->second.getPointer()))
+ if (CallInst* CD = dyn_cast<CallInst>(NonLocalDepInst))
cdep = CD;
else {
valueNumbering.insert(std::make_pair(V, nextValueNumber));
@@ -721,8 +722,6 @@
AU.addPreserved<AliasAnalysis>();
}
- typedef MemoryDependenceAnalysis::DepResultTy DepResultTy;
-
// Helper fuctions
// FIXME: eliminate or document these better
bool processLoad(LoadInst* L,
@@ -866,7 +865,7 @@
MemoryDependenceAnalysis& MD = getAnalysis<MemoryDependenceAnalysis>();
// Find the non-local dependencies of the load
- DenseMap<BasicBlock*, DepResultTy> deps;
+ DenseMap<BasicBlock*, MemDepResult> deps;
MD.getNonLocalDependency(L, deps);
// If we had to process more than one hundred blocks to find the
@@ -878,19 +877,19 @@
DenseMap<BasicBlock*, Value*> repl;
// Filter out useless results (non-locals, etc)
- for (DenseMap<BasicBlock*, DepResultTy>::iterator I = deps.begin(),
+ for (DenseMap<BasicBlock*, MemDepResult>::iterator I = deps.begin(),
E = deps.end(); I != E; ++I) {
- if (I->second.getInt() == MemoryDependenceAnalysis::None)
+ if (I->second.isNone())
return false;
- if (I->second.getInt() == MemoryDependenceAnalysis::NonLocal)
+ if (I->second.isNonLocal())
continue;
- if (StoreInst* S = dyn_cast<StoreInst>(I->second.getPointer())) {
+ if (StoreInst* S = dyn_cast<StoreInst>(I->second.getInst())) {
if (S->getPointerOperand() != L->getPointerOperand())
return false;
repl[I->first] = S->getOperand(0);
- } else if (LoadInst* LD = dyn_cast<LoadInst>(I->second.getPointer())) {
+ } else if (LoadInst* LD = dyn_cast<LoadInst>(I->second.getInst())) {
if (LD->getPointerOperand() != L->getPointerOperand())
return false;
repl[I->first] = LD;
@@ -941,8 +940,8 @@
// ... to a pointer that has been loaded from before...
MemoryDependenceAnalysis& MD = getAnalysis<MemoryDependenceAnalysis>();
bool removedNonLocal = false;
- DepResultTy dep = MD.getDependency(L);
- if (dep.getInt() == MemoryDependenceAnalysis::NonLocal &&
+ MemDepResult dep = MD.getDependency(L);
+ if (dep.isNonLocal() &&
L->getParent() != &L->getParent()->getParent()->getEntryBlock()) {
removedNonLocal = processNonLocalLoad(L, toErase);
@@ -957,10 +956,9 @@
// Walk up the dependency chain until we either find
// a dependency we can use, or we can't walk any further
- while (dep.getInt() == MemoryDependenceAnalysis::Normal &&
- (isa<LoadInst>(dep.getPointer()) || isa<StoreInst>(dep.getPointer()))){
+ while (Instruction *DepInst = dep.getInst()) {
// ... that depends on a store ...
- if (StoreInst* S = dyn_cast<StoreInst>(dep.getPointer())) {
+ if (StoreInst* S = dyn_cast<StoreInst>(DepInst)) {
if (S->getPointerOperand() == pointer) {
// Remove it!
MD.removeInstruction(L);
@@ -974,11 +972,14 @@
// Whether we removed it or not, we can't
// go any further
break;
+ } else if (!isa<LoadInst>(DepInst)) {
+ // Only want to handle loads below.
+ break;
} else if (!last) {
// If we don't depend on a store, and we haven't
// been loaded before, bail.
break;
- } else if (dep.getPointer() == last) {
+ } else if (DepInst == last) {
// Remove it!
MD.removeInstruction(L);
@@ -989,15 +990,14 @@
break;
} else {
- dep = MD.getDependency(L, dep.getPointer());
+ dep = MD.getDependency(L, DepInst);
}
}
- if (dep.getInt() == MemoryDependenceAnalysis::Normal &&
- isa<AllocationInst>(dep.getPointer())) {
+ if (AllocationInst *DepAI = dyn_cast_or_null<AllocationInst>(dep.getInst())) {
// Check that this load is actually from the
// allocation we found
- if (L->getOperand(0)->getUnderlyingObject() == dep.getPointer()) {
+ if (L->getOperand(0)->getUnderlyingObject() == DepAI) {
// If this load depends directly on an allocation, there isn't
// anything stored there; therefore, we can optimize this load
// to undef.
Modified: llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp?rev=60231&r1=60230&r2=60231&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp Fri Nov 28 20:29:27 2008
@@ -629,18 +629,17 @@
// The are two possible optimizations we can do for memcpy:
// a) memcpy-memcpy xform which exposes redundance for DSE
// b) call-memcpy xform for return slot optimization
- MemoryDependenceAnalysis::DepResultTy dep = MD.getDependency(M);
- if (dep.getInt() == MemoryDependenceAnalysis::None ||
- dep.getInt() == MemoryDependenceAnalysis::NonLocal)
+ MemDepResult dep = MD.getDependency(M);
+ if (!dep.isNormal())
return false;
- else if (!isa<MemCpyInst>(dep.getPointer())) {
- if (CallInst* C = dyn_cast<CallInst>(dep.getPointer()))
+ else if (!isa<MemCpyInst>(dep.getInst())) {
+ if (CallInst* C = dyn_cast<CallInst>(dep.getInst()))
return performCallSlotOptzn(M, C);
else
return false;
}
- MemCpyInst* MDep = cast<MemCpyInst>(dep.getPointer());
+ MemCpyInst* MDep = cast<MemCpyInst>(dep.getInst());
// We can only transforms memcpy's where the dest of one is the source of the
// other
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