mirror of
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Reimplement the internal abstraction used by MemDep in terms
of a pointer/int pair instead of a manually bitmangled pointer. This forces clients to think a little more about checking the appropriate pieces and will be useful for internal implementation improvements later. I'm not particularly happy with this. After going through this I don't think that the clients of memdep should be exposed to the internal type at all. I'll fix this in a subsequent commit. This has no functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60230 91177308-0d34-0410-b5e6-96231b3b80d8
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@ -17,6 +17,7 @@
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#include "llvm/Pass.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/SmallPtrSet.h"
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#include "llvm/ADT/PointerIntPair.h"
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namespace llvm {
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class Function;
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@ -29,38 +30,54 @@ namespace llvm {
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/// It builds on alias analysis information, and tries to provide a lazy,
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/// caching interface to a common kind of alias information query.
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class MemoryDependenceAnalysis : public FunctionPass {
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public:
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/// DepType - This enum is used to indicate what flavor of dependence this
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/// is. If the type is Normal, there is an associated instruction pointer.
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enum DepType {
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/// Normal - This is a normal instruction dependence. The pointer member
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/// of the DepResultTy pair holds the instruction.
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Normal = 0,
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/// None - This dependence type indicates that the query does not depend
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/// on any instructions, either because it scanned to the start of the
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/// function or it scanned to the definition of the memory
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/// (alloca/malloc).
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None,
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/// NonLocal - This marker indicates that the query has no dependency in
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/// the specified block. To find out more, the client should query other
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/// predecessor blocks.
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NonLocal,
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/// Dirty - This is an internal marker indicating that that a cache entry
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/// is dirty.
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Dirty
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};
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typedef PointerIntPair<Instruction*, 2, DepType> DepResultTy;
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private:
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// A map from instructions to their dependency, with a boolean
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// flags for whether this mapping is confirmed or not.
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typedef DenseMap<Instruction*, std::pair<Instruction*, bool> > depMapType;
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depMapType depGraphLocal;
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typedef DenseMap<Instruction*,
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std::pair<DepResultTy, bool> > LocalDepMapType;
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LocalDepMapType LocalDeps;
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// A map from instructions to their non-local dependencies.
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typedef DenseMap<Instruction*,
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DenseMap<BasicBlock*, Value*> > nonLocalDepMapType;
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DenseMap<BasicBlock*, DepResultTy> > nonLocalDepMapType;
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nonLocalDepMapType depGraphNonLocal;
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// A reverse mapping from dependencies to the dependees. This is
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// used when removing instructions to keep the cache coherent.
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typedef DenseMap<Value*, SmallPtrSet<Instruction*, 4> > reverseDepMapType;
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typedef DenseMap<DepResultTy,
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SmallPtrSet<Instruction*, 4> > reverseDepMapType;
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reverseDepMapType reverseDep;
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// A reverse mapping form dependencies to the non-local dependees.
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reverseDepMapType reverseDepNonLocal;
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public:
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// Special marker indicating that the query has no dependency
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// in the specified block.
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static Instruction* const NonLocal;
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// Special marker indicating that the query has no dependency at all
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static Instruction* const None;
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// Special marker indicating a dirty cache entry
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static Instruction* const Dirty;
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static char ID; // Class identification, replacement for typeinfo
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MemoryDependenceAnalysis() : FunctionPass(&ID) {}
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static char ID;
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/// Pass Implementation stuff. This doesn't do any analysis.
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///
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@ -68,7 +85,7 @@ namespace llvm {
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/// Clean up memory in between runs
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void releaseMemory() {
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depGraphLocal.clear();
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LocalDeps.clear();
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depGraphNonLocal.clear();
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reverseDep.clear();
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reverseDepNonLocal.clear();
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@ -81,33 +98,33 @@ namespace llvm {
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/// getDependency - Return the instruction on which a memory operation
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/// depends, starting with start.
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Instruction* getDependency(Instruction* query, Instruction* start = 0,
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BasicBlock* block = 0);
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DepResultTy getDependency(Instruction *query, Instruction *start = 0,
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BasicBlock *block = 0);
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/// getNonLocalDependency - Fills the passed-in map with the non-local
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/// dependencies of the queries. The map will contain NonLocal for
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/// blocks between the query and its dependencies.
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void getNonLocalDependency(Instruction* query,
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DenseMap<BasicBlock*, Value*>& resp);
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DenseMap<BasicBlock*, DepResultTy> &resp);
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/// removeInstruction - Remove an instruction from the dependence analysis,
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/// updating the dependence of instructions that previously depended on it.
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void removeInstruction(Instruction* rem);
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void removeInstruction(Instruction *InstToRemove);
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/// dropInstruction - Remove an instruction from the analysis, making
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/// absolutely conservative assumptions when updating the cache. This is
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/// useful, for example when an instruction is changed rather than removed.
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void dropInstruction(Instruction* drop);
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void dropInstruction(Instruction *InstToDrop);
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private:
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/// verifyRemoved - Verify that the specified instruction does not occur
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/// in our internal data structures.
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void verifyRemoved(Instruction *Inst) const;
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Instruction* getCallSiteDependency(CallSite C, Instruction* start,
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BasicBlock* block);
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DepResultTy getCallSiteDependency(CallSite C, Instruction* start,
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BasicBlock* block);
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void nonLocalHelper(Instruction* query, BasicBlock* block,
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DenseMap<BasicBlock*, Value*>& resp);
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DenseMap<BasicBlock*, DepResultTy>& resp);
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};
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} // End llvm namespace
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@ -41,10 +41,6 @@ STATISTIC(NumUncacheNonlocal, "Number of uncached non-local responses");
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char MemoryDependenceAnalysis::ID = 0;
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Instruction* const MemoryDependenceAnalysis::NonLocal = (Instruction*)-3;
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Instruction* const MemoryDependenceAnalysis::None = (Instruction*)-4;
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Instruction* const MemoryDependenceAnalysis::Dirty = (Instruction*)-5;
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// Register this pass...
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static RegisterPass<MemoryDependenceAnalysis> X("memdep",
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"Memory Dependence Analysis", false, true);
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@ -52,18 +48,19 @@ static RegisterPass<MemoryDependenceAnalysis> X("memdep",
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/// verifyRemoved - Verify that the specified instruction does not occur
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/// in our internal data structures.
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void MemoryDependenceAnalysis::verifyRemoved(Instruction *D) const {
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for (depMapType::const_iterator I = depGraphLocal.begin(),
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E = depGraphLocal.end(); I != E; ++I) {
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for (LocalDepMapType::const_iterator I = LocalDeps.begin(),
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E = LocalDeps.end(); I != E; ++I) {
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assert(I->first != D && "Inst occurs in data structures");
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assert(I->second.first != D && "Inst occurs in data structures");
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assert(I->second.first.getPointer() != D &&
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"Inst occurs in data structures");
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}
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for (nonLocalDepMapType::const_iterator I = depGraphNonLocal.begin(),
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E = depGraphNonLocal.end(); I != E; ++I) {
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assert(I->first != D && "Inst occurs in data structures");
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for (DenseMap<BasicBlock*, Value*>::iterator II = I->second.begin(),
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for (DenseMap<BasicBlock*, DepResultTy>::iterator II = I->second.begin(),
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EE = I->second.end(); II != EE; ++II)
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assert(II->second != D && "Inst occurs in data structures");
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assert(II->second.getPointer() != D && "Inst occurs in data structures");
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}
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for (reverseDepMapType::const_iterator I = reverseDep.begin(),
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@ -90,12 +87,10 @@ void MemoryDependenceAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
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/// getCallSiteDependency - Private helper for finding the local dependencies
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/// of a call site.
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Instruction* MemoryDependenceAnalysis::getCallSiteDependency(CallSite C,
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Instruction* start,
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BasicBlock* block) {
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std::pair<Instruction*, bool>& cachedResult =
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depGraphLocal[C.getInstruction()];
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MemoryDependenceAnalysis::DepResultTy
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MemoryDependenceAnalysis::
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getCallSiteDependency(CallSite C, Instruction *start, BasicBlock *block) {
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std::pair<DepResultTy, bool> &cachedResult = LocalDeps[C.getInstruction()];
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AliasAnalysis& AA = getAnalysis<AliasAnalysis>();
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TargetData& TD = getAnalysis<TargetData>();
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BasicBlock::iterator blockBegin = C.getInstruction()->getParent()->begin();
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@ -141,11 +136,11 @@ Instruction* MemoryDependenceAnalysis::getCallSiteDependency(CallSite C,
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AA.getModRefBehavior(CallSite::get(QI));
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if (result != AliasAnalysis::DoesNotAccessMemory) {
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if (!start && !block) {
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cachedResult.first = QI;
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cachedResult.first = DepResultTy(QI, Normal);
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cachedResult.second = true;
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reverseDep[QI].insert(C.getInstruction());
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reverseDep[DepResultTy(QI, Normal)].insert(C.getInstruction());
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}
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return QI;
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return DepResultTy(QI, Normal);
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} else {
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continue;
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}
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@ -154,33 +149,33 @@ Instruction* MemoryDependenceAnalysis::getCallSiteDependency(CallSite C,
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if (AA.getModRefInfo(C, pointer, pointerSize) != AliasAnalysis::NoModRef) {
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if (!start && !block) {
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cachedResult.first = QI;
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cachedResult.first = DepResultTy(QI, Normal);
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cachedResult.second = true;
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reverseDep[QI].insert(C.getInstruction());
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reverseDep[DepResultTy(QI, Normal)].insert(C.getInstruction());
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}
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return QI;
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return DepResultTy(QI, Normal);
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}
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}
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// No dependence found
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cachedResult.first = NonLocal;
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cachedResult.first = DepResultTy(0, NonLocal);
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cachedResult.second = true;
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reverseDep[NonLocal].insert(C.getInstruction());
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return NonLocal;
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reverseDep[DepResultTy(0, NonLocal)].insert(C.getInstruction());
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return DepResultTy(0, NonLocal);
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}
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/// nonLocalHelper - Private helper used to calculate non-local dependencies
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/// by doing DFS on the predecessors of a block to find its dependencies
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/// by doing DFS on the predecessors of a block to find its dependencies.
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void MemoryDependenceAnalysis::nonLocalHelper(Instruction* query,
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BasicBlock* block,
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DenseMap<BasicBlock*, Value*>& resp) {
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DenseMap<BasicBlock*, DepResultTy> &resp) {
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// Set of blocks that we've already visited in our DFS
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SmallPtrSet<BasicBlock*, 4> visited;
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// If we're updating a dirtied cache entry, we don't need to reprocess
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// already computed entries.
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for (DenseMap<BasicBlock*, Value*>::iterator I = resp.begin(),
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for (DenseMap<BasicBlock*, DepResultTy>::iterator I = resp.begin(),
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E = resp.end(); I != E; ++I)
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if (I->second != Dirty)
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if (I->second.getInt() != Dirty)
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visited.insert(I->first);
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// Current stack of the DFS
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@ -204,8 +199,8 @@ void MemoryDependenceAnalysis::nonLocalHelper(Instruction* query,
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if (BB != block) {
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visited.insert(BB);
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Instruction* localDep = getDependency(query, 0, BB);
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if (localDep != NonLocal) {
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DepResultTy localDep = getDependency(query, 0, BB);
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if (localDep.getInt() != NonLocal) {
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resp.insert(std::make_pair(BB, localDep));
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stack.pop_back();
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@ -217,8 +212,8 @@ void MemoryDependenceAnalysis::nonLocalHelper(Instruction* query,
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} else if (BB == block) {
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visited.insert(BB);
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Instruction* localDep = getDependency(query, 0, BB);
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if (localDep != query)
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DepResultTy localDep = getDependency(query, 0, BB);
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if (localDep != DepResultTy(query, Normal))
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resp.insert(std::make_pair(BB, localDep));
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stack.pop_back();
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@ -246,12 +241,12 @@ void MemoryDependenceAnalysis::nonLocalHelper(Instruction* query,
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// If we didn't insert because we have no predecessors, then this
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// query has no dependency at all.
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else if (!inserted && !predOnStack) {
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resp.insert(std::make_pair(BB, None));
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resp.insert(std::make_pair(BB, DepResultTy(0, None)));
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// If we didn't insert because our predecessors are already on the stack,
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// then we might still have a dependency, but it will be discovered during
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// backtracking.
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} else if (!inserted && predOnStack){
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resp.insert(std::make_pair(BB, NonLocal));
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resp.insert(std::make_pair(BB, DepResultTy(0, NonLocal)));
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}
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stack.pop_back();
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@ -262,21 +257,21 @@ void MemoryDependenceAnalysis::nonLocalHelper(Instruction* query,
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/// dependencies of the queries. The map will contain NonLocal for
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/// blocks between the query and its dependencies.
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void MemoryDependenceAnalysis::getNonLocalDependency(Instruction* query,
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DenseMap<BasicBlock*, Value*>& resp) {
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DenseMap<BasicBlock*, DepResultTy> &resp) {
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if (depGraphNonLocal.count(query)) {
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DenseMap<BasicBlock*, Value*>& cached = depGraphNonLocal[query];
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DenseMap<BasicBlock*, DepResultTy> &cached = depGraphNonLocal[query];
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NumCacheNonlocal++;
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SmallVector<BasicBlock*, 4> dirtied;
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for (DenseMap<BasicBlock*, Value*>::iterator I = cached.begin(),
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for (DenseMap<BasicBlock*, DepResultTy>::iterator I = cached.begin(),
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E = cached.end(); I != E; ++I)
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if (I->second == Dirty)
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if (I->second.getInt() == Dirty)
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dirtied.push_back(I->first);
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for (SmallVector<BasicBlock*, 4>::iterator I = dirtied.begin(),
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E = dirtied.end(); I != E; ++I) {
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Instruction* localDep = getDependency(query, 0, *I);
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if (localDep != NonLocal)
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DepResultTy localDep = getDependency(query, 0, *I);
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if (localDep.getInt() != NonLocal)
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cached[*I] = localDep;
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else {
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cached.erase(*I);
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@ -287,8 +282,8 @@ void MemoryDependenceAnalysis::getNonLocalDependency(Instruction* query,
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resp = cached;
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// Update the reverse non-local dependency cache
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for (DenseMap<BasicBlock*, Value*>::iterator I = resp.begin(), E = resp.end();
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I != E; ++I)
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for (DenseMap<BasicBlock*, DepResultTy>::iterator I = resp.begin(),
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E = resp.end(); I != E; ++I)
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reverseDepNonLocal[I->second].insert(query);
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return;
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@ -299,8 +294,8 @@ void MemoryDependenceAnalysis::getNonLocalDependency(Instruction* query,
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nonLocalHelper(query, query->getParent(), resp);
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// Update the non-local dependency cache
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for (DenseMap<BasicBlock*, Value*>::iterator I = resp.begin(), E = resp.end();
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I != E; ++I) {
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for (DenseMap<BasicBlock*, DepResultTy>::iterator I = resp.begin(),
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E = resp.end(); I != E; ++I) {
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depGraphNonLocal[query].insert(*I);
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reverseDepNonLocal[I->second].insert(query);
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}
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@ -309,21 +304,24 @@ void MemoryDependenceAnalysis::getNonLocalDependency(Instruction* query,
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/// getDependency - Return the instruction on which a memory operation
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/// depends. The local parameter indicates if the query should only
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/// evaluate dependencies within the same basic block.
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Instruction* MemoryDependenceAnalysis::getDependency(Instruction* query,
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Instruction* start,
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BasicBlock* block) {
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MemoryDependenceAnalysis::DepResultTy
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MemoryDependenceAnalysis::getDependency(Instruction *query,
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Instruction *start,
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BasicBlock *block) {
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// Start looking for dependencies with the queried inst
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BasicBlock::iterator QI = query;
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// Check for a cached result
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std::pair<Instruction*, bool>& cachedResult = depGraphLocal[query];
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std::pair<DepResultTy, bool>& cachedResult = LocalDeps[query];
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// If we have a _confirmed_ cached entry, return it
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if (!block && !start) {
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if (cachedResult.second)
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return cachedResult.first;
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else if (cachedResult.first && cachedResult.first != NonLocal)
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// If we have an unconfirmed cached entry, we can start our search from there
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QI = cachedResult.first;
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else if (cachedResult.first.getInt() == Normal &&
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cachedResult.first.getPointer())
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// If we have an unconfirmed cached entry, we can start our search from
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// it.
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QI = cachedResult.first.getPointer();
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}
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if (start)
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@ -357,9 +355,9 @@ Instruction* MemoryDependenceAnalysis::getDependency(Instruction* query,
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} else if (CallSite::get(query).getInstruction() != 0)
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return getCallSiteDependency(CallSite::get(query), start, block);
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else if (isa<AllocationInst>(query))
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return None;
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return DepResultTy(0, None);
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else
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return None;
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return DepResultTy(0, None);
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BasicBlock::iterator blockBegin = block ? block->begin()
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: query->getParent()->begin();
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@ -375,12 +373,12 @@ Instruction* MemoryDependenceAnalysis::getDependency(Instruction* query,
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// All volatile loads/stores depend on each other
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if (queryIsVolatile && S->isVolatile()) {
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if (!start && !block) {
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cachedResult.first = S;
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cachedResult.first = DepResultTy(S, Normal);
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cachedResult.second = true;
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reverseDep[S].insert(query);
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reverseDep[DepResultTy(S, Normal)].insert(query);
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}
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return S;
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return DepResultTy(S, Normal);
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}
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pointer = S->getPointerOperand();
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@ -389,12 +387,12 @@ Instruction* MemoryDependenceAnalysis::getDependency(Instruction* query,
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// All volatile loads/stores depend on each other
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if (queryIsVolatile && L->isVolatile()) {
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if (!start && !block) {
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cachedResult.first = L;
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cachedResult.first = DepResultTy(L, Normal);
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cachedResult.second = true;
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reverseDep[L].insert(query);
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reverseDep[DepResultTy(L, Normal)].insert(query);
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}
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return L;
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return DepResultTy(L, Normal);
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}
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pointer = L->getPointerOperand();
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@ -417,7 +415,7 @@ Instruction* MemoryDependenceAnalysis::getDependency(Instruction* query,
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} else if (CallSite::get(QI).getInstruction() != 0) {
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// Call insts need special handling. Check if they can modify our pointer
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AliasAnalysis::ModRefResult MR = AA.getModRefInfo(CallSite::get(QI),
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dependee, dependeeSize);
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dependee, dependeeSize);
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if (MR != AliasAnalysis::NoModRef) {
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// Loads don't depend on read-only calls
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@ -425,12 +423,11 @@ Instruction* MemoryDependenceAnalysis::getDependency(Instruction* query,
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continue;
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if (!start && !block) {
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cachedResult.first = QI;
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cachedResult.first = DepResultTy(QI, Normal);
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cachedResult.second = true;
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reverseDep[QI].insert(query);
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reverseDep[DepResultTy(QI, Normal)].insert(query);
|
||||
}
|
||||
|
||||
return QI;
|
||||
return DepResultTy(QI, Normal);
|
||||
} else {
|
||||
continue;
|
||||
}
|
||||
@ -448,64 +445,63 @@ Instruction* MemoryDependenceAnalysis::getDependency(Instruction* query,
|
||||
continue;
|
||||
|
||||
if (!start && !block) {
|
||||
cachedResult.first = QI;
|
||||
cachedResult.first = DepResultTy(QI, Normal);
|
||||
cachedResult.second = true;
|
||||
reverseDep[QI].insert(query);
|
||||
reverseDep[DepResultTy(QI, Normal)].insert(query);
|
||||
}
|
||||
|
||||
return QI;
|
||||
return DepResultTy(QI, Normal);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// If we found nothing, return the non-local flag
|
||||
if (!start && !block) {
|
||||
cachedResult.first = NonLocal;
|
||||
cachedResult.first = DepResultTy(0, NonLocal);
|
||||
cachedResult.second = true;
|
||||
reverseDep[NonLocal].insert(query);
|
||||
reverseDep[DepResultTy(0, NonLocal)].insert(query);
|
||||
}
|
||||
|
||||
return NonLocal;
|
||||
return DepResultTy(0, NonLocal);
|
||||
}
|
||||
|
||||
/// dropInstruction - Remove an instruction from the analysis, making
|
||||
/// absolutely conservative assumptions when updating the cache. This is
|
||||
/// useful, for example when an instruction is changed rather than removed.
|
||||
void MemoryDependenceAnalysis::dropInstruction(Instruction* drop) {
|
||||
depMapType::iterator depGraphEntry = depGraphLocal.find(drop);
|
||||
if (depGraphEntry != depGraphLocal.end())
|
||||
LocalDepMapType::iterator depGraphEntry = LocalDeps.find(drop);
|
||||
if (depGraphEntry != LocalDeps.end())
|
||||
reverseDep[depGraphEntry->second.first].erase(drop);
|
||||
|
||||
// Drop dependency information for things that depended on this instr
|
||||
SmallPtrSet<Instruction*, 4>& set = reverseDep[drop];
|
||||
SmallPtrSet<Instruction*, 4>& set = reverseDep[DepResultTy(drop, Normal)];
|
||||
for (SmallPtrSet<Instruction*, 4>::iterator I = set.begin(), E = set.end();
|
||||
I != E; ++I)
|
||||
depGraphLocal.erase(*I);
|
||||
LocalDeps.erase(*I);
|
||||
|
||||
depGraphLocal.erase(drop);
|
||||
reverseDep.erase(drop);
|
||||
LocalDeps.erase(drop);
|
||||
reverseDep.erase(DepResultTy(drop, Normal));
|
||||
|
||||
for (DenseMap<BasicBlock*, Value*>::iterator DI =
|
||||
depGraphNonLocal[drop].begin(), DE = depGraphNonLocal[drop].end();
|
||||
for (DenseMap<BasicBlock*, DepResultTy>::iterator DI =
|
||||
depGraphNonLocal[drop].begin(), DE = depGraphNonLocal[drop].end();
|
||||
DI != DE; ++DI)
|
||||
if (DI->second != None)
|
||||
if (DI->second.getInt() != None)
|
||||
reverseDepNonLocal[DI->second].erase(drop);
|
||||
|
||||
if (reverseDepNonLocal.count(drop)) {
|
||||
SmallPtrSet<Instruction*, 4>& set = reverseDepNonLocal[drop];
|
||||
if (reverseDepNonLocal.count(DepResultTy(drop, Normal))) {
|
||||
SmallPtrSet<Instruction*, 4>& set =
|
||||
reverseDepNonLocal[DepResultTy(drop, Normal)];
|
||||
for (SmallPtrSet<Instruction*, 4>::iterator I = set.begin(), E = set.end();
|
||||
I != E; ++I)
|
||||
for (DenseMap<BasicBlock*, Value*>::iterator DI =
|
||||
for (DenseMap<BasicBlock*, DepResultTy>::iterator DI =
|
||||
depGraphNonLocal[*I].begin(), DE = depGraphNonLocal[*I].end();
|
||||
DI != DE; ++DI)
|
||||
if (DI->second == drop)
|
||||
DI->second = Dirty;
|
||||
if (DI->second == DepResultTy(drop, Normal))
|
||||
DI->second = DepResultTy(0, Dirty);
|
||||
}
|
||||
|
||||
reverseDepNonLocal.erase(drop);
|
||||
nonLocalDepMapType::iterator I = depGraphNonLocal.find(drop);
|
||||
if (I != depGraphNonLocal.end())
|
||||
depGraphNonLocal.erase(I);
|
||||
reverseDepNonLocal.erase(DepResultTy(drop, Normal));
|
||||
depGraphNonLocal.erase(drop);
|
||||
}
|
||||
|
||||
/// removeInstruction - Remove an instruction from the dependence analysis,
|
||||
@ -514,10 +510,10 @@ void MemoryDependenceAnalysis::dropInstruction(Instruction* drop) {
|
||||
void MemoryDependenceAnalysis::removeInstruction(Instruction *RemInst) {
|
||||
// Walk through the Non-local dependencies, removing this one as the value
|
||||
// for any cached queries.
|
||||
for (DenseMap<BasicBlock*, Value*>::iterator DI =
|
||||
for (DenseMap<BasicBlock*, DepResultTy>::iterator DI =
|
||||
depGraphNonLocal[RemInst].begin(), DE = depGraphNonLocal[RemInst].end();
|
||||
DI != DE; ++DI)
|
||||
if (DI->second != None)
|
||||
if (DI->second.getInt() != None)
|
||||
reverseDepNonLocal[DI->second].erase(RemInst);
|
||||
|
||||
// Shortly after this, we will look for things that depend on RemInst. In
|
||||
@ -525,36 +521,34 @@ void MemoryDependenceAnalysis::removeInstruction(Instruction *RemInst) {
|
||||
// could completely delete any entries that depend on this, but it is better
|
||||
// to make a more accurate approximation where possible. Compute that better
|
||||
// approximation if we can.
|
||||
Instruction *NewDependency = 0;
|
||||
DepResultTy NewDependency;
|
||||
bool NewDependencyConfirmed = false;
|
||||
|
||||
// If we have a cached local dependence query for this instruction, remove it.
|
||||
//
|
||||
depMapType::iterator LocalDepEntry = depGraphLocal.find(RemInst);
|
||||
if (LocalDepEntry != depGraphLocal.end()) {
|
||||
Instruction *LocalDepInst = LocalDepEntry->second.first;
|
||||
LocalDepMapType::iterator LocalDepEntry = LocalDeps.find(RemInst);
|
||||
if (LocalDepEntry != LocalDeps.end()) {
|
||||
DepResultTy LocalDep = LocalDepEntry->second.first;
|
||||
bool IsConfirmed = LocalDepEntry->second.second;
|
||||
|
||||
// Remove this local dependency info.
|
||||
depGraphLocal.erase(LocalDepEntry);
|
||||
LocalDeps.erase(LocalDepEntry);
|
||||
|
||||
// Remove us from DepInst's reverse set now that the local dep info is gone.
|
||||
reverseDep[LocalDepInst].erase(RemInst);
|
||||
reverseDep[LocalDep].erase(RemInst);
|
||||
|
||||
// If we have unconfirmed info, don't trust it.
|
||||
if (IsConfirmed) {
|
||||
// If we have a confirmed non-local flag, use it.
|
||||
if (LocalDepInst == NonLocal || LocalDepInst == None) {
|
||||
if (LocalDep.getInt() == NonLocal || LocalDep.getInt() == None) {
|
||||
// The only time this dependency is confirmed is if it is non-local.
|
||||
NewDependency = LocalDepInst;
|
||||
NewDependency = LocalDep;
|
||||
NewDependencyConfirmed = true;
|
||||
} else {
|
||||
// If we have dep info for RemInst, set them to it.
|
||||
NewDependency = next(BasicBlock::iterator(LocalDepInst));
|
||||
|
||||
// Don't use RI for the new dependency!
|
||||
if (NewDependency == RemInst)
|
||||
NewDependency = 0;
|
||||
Instruction *NDI = next(BasicBlock::iterator(LocalDep.getPointer()));
|
||||
if (NDI != RemInst) // Don't use RemInst for the new dependency!
|
||||
NewDependency = DepResultTy(NDI, Normal);
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -563,12 +557,13 @@ void MemoryDependenceAnalysis::removeInstruction(Instruction *RemInst) {
|
||||
// use the immediate successor of RemInst. We use the successor because
|
||||
// getDependence starts by checking the immediate predecessor of what is in
|
||||
// the cache.
|
||||
if (NewDependency == 0)
|
||||
NewDependency = next(BasicBlock::iterator(RemInst));
|
||||
if (NewDependency == DepResultTy(0, Normal))
|
||||
NewDependency = DepResultTy(next(BasicBlock::iterator(RemInst)), Normal);
|
||||
|
||||
// Loop over all of the things that depend on the instruction we're removing.
|
||||
//
|
||||
reverseDepMapType::iterator ReverseDepIt = reverseDep.find(RemInst);
|
||||
reverseDepMapType::iterator ReverseDepIt =
|
||||
reverseDep.find(DepResultTy(RemInst, Normal));
|
||||
if (ReverseDepIt != reverseDep.end()) {
|
||||
SmallPtrSet<Instruction*, 4> &ReverseDeps = ReverseDepIt->second;
|
||||
for (SmallPtrSet<Instruction*, 4>::iterator I = ReverseDeps.begin(),
|
||||
@ -580,28 +575,29 @@ void MemoryDependenceAnalysis::removeInstruction(Instruction *RemInst) {
|
||||
if (InstDependingOnRemInst == RemInst) continue;
|
||||
|
||||
// Insert the new dependencies.
|
||||
depGraphLocal[InstDependingOnRemInst] =
|
||||
LocalDeps[InstDependingOnRemInst] =
|
||||
std::make_pair(NewDependency, NewDependencyConfirmed);
|
||||
|
||||
// If our NewDependency is an instruction, make sure to remember that new
|
||||
// things depend on it.
|
||||
if (NewDependency != NonLocal && NewDependency != None)
|
||||
// FIXME: Just insert all deps!
|
||||
if (NewDependency.getInt() != NonLocal && NewDependency.getInt() != None)
|
||||
reverseDep[NewDependency].insert(InstDependingOnRemInst);
|
||||
}
|
||||
reverseDep.erase(RemInst);
|
||||
reverseDep.erase(DepResultTy(RemInst, Normal));
|
||||
}
|
||||
|
||||
ReverseDepIt = reverseDepNonLocal.find(RemInst);
|
||||
ReverseDepIt = reverseDepNonLocal.find(DepResultTy(RemInst, Normal));
|
||||
if (ReverseDepIt != reverseDepNonLocal.end()) {
|
||||
SmallPtrSet<Instruction*, 4>& set = ReverseDepIt->second;
|
||||
for (SmallPtrSet<Instruction*, 4>::iterator I = set.begin(), E = set.end();
|
||||
I != E; ++I)
|
||||
for (DenseMap<BasicBlock*, Value*>::iterator DI =
|
||||
for (DenseMap<BasicBlock*, DepResultTy>::iterator DI =
|
||||
depGraphNonLocal[*I].begin(), DE = depGraphNonLocal[*I].end();
|
||||
DI != DE; ++DI)
|
||||
if (DI->second == RemInst)
|
||||
DI->second = Dirty;
|
||||
reverseDepNonLocal.erase(RemInst);
|
||||
if (DI->second == DepResultTy(RemInst, Normal))
|
||||
DI->second = DepResultTy(0, Dirty);
|
||||
reverseDepNonLocal.erase(ReverseDepIt);
|
||||
}
|
||||
|
||||
depGraphNonLocal.erase(RemInst);
|
||||
|
@ -47,8 +47,10 @@ namespace {
|
||||
return Changed;
|
||||
}
|
||||
|
||||
typedef MemoryDependenceAnalysis::DepResultTy DepResultTy;
|
||||
|
||||
bool runOnBasicBlock(BasicBlock &BB);
|
||||
bool handleFreeWithNonTrivialDependency(FreeInst *F, Instruction *Dep);
|
||||
bool handleFreeWithNonTrivialDependency(FreeInst *F, DepResultTy Dep);
|
||||
bool handleEndBlock(BasicBlock &BB);
|
||||
bool RemoveUndeadPointers(Value* pointer, uint64_t killPointerSize,
|
||||
BasicBlock::iterator& BBI,
|
||||
@ -108,17 +110,16 @@ bool DSE::runOnBasicBlock(BasicBlock &BB) {
|
||||
|
||||
// ... to a pointer that has been stored to before...
|
||||
if (last) {
|
||||
Instruction* dep = MD.getDependency(Inst);
|
||||
DepResultTy dep = MD.getDependency(Inst);
|
||||
bool deletedStore = false;
|
||||
|
||||
// ... and no other memory dependencies are between them....
|
||||
while (dep != MemoryDependenceAnalysis::None &&
|
||||
dep != MemoryDependenceAnalysis::NonLocal &&
|
||||
isa<StoreInst>(dep)) {
|
||||
if (dep != last ||
|
||||
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);
|
||||
dep = MD.getDependency(Inst, dep.getPointer());
|
||||
continue;
|
||||
}
|
||||
|
||||
@ -151,14 +152,14 @@ bool DSE::runOnBasicBlock(BasicBlock &BB) {
|
||||
// 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!
|
||||
Instruction* dep = MD.getDependency(S);
|
||||
DepResultTy dep = MD.getDependency(S);
|
||||
DominatorTree& DT = getAnalysis<DominatorTree>();
|
||||
|
||||
if (!S->isVolatile() && S->getParent() == L->getParent() &&
|
||||
S->getPointerOperand() == L->getPointerOperand() &&
|
||||
(dep == MemoryDependenceAnalysis::None ||
|
||||
dep == MemoryDependenceAnalysis::NonLocal ||
|
||||
DT.dominates(dep, L))) {
|
||||
(dep.getInt() == MemoryDependenceAnalysis::None ||
|
||||
dep.getInt() == MemoryDependenceAnalysis::NonLocal ||
|
||||
DT.dominates(dep.getPointer(), L))) {
|
||||
|
||||
DeleteDeadInstruction(S);
|
||||
if (!isa<TerminatorInst>(BB.begin()))
|
||||
@ -184,15 +185,15 @@ bool DSE::runOnBasicBlock(BasicBlock &BB) {
|
||||
|
||||
/// handleFreeWithNonTrivialDependency - Handle frees of entire structures whose
|
||||
/// dependency is a store to a field of that structure.
|
||||
bool DSE::handleFreeWithNonTrivialDependency(FreeInst* F, Instruction* dep) {
|
||||
bool DSE::handleFreeWithNonTrivialDependency(FreeInst* F, DepResultTy dep) {
|
||||
TargetData &TD = getAnalysis<TargetData>();
|
||||
AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
|
||||
|
||||
if (dep == MemoryDependenceAnalysis::None ||
|
||||
dep == MemoryDependenceAnalysis::NonLocal)
|
||||
if (dep.getInt() == MemoryDependenceAnalysis::None ||
|
||||
dep.getInt() == MemoryDependenceAnalysis::NonLocal)
|
||||
return false;
|
||||
|
||||
StoreInst* dependency = dyn_cast<StoreInst>(dep);
|
||||
StoreInst* dependency = dyn_cast<StoreInst>(dep.getPointer());
|
||||
if (!dependency)
|
||||
return false;
|
||||
else if (dependency->isVolatile())
|
||||
|
@ -456,19 +456,21 @@ uint32_t ValueTable::lookup_or_add(Value* V) {
|
||||
return nextValueNumber++;
|
||||
}
|
||||
|
||||
Instruction* local_dep = MD->getDependency(C);
|
||||
MemoryDependenceAnalysis::DepResultTy local_dep = MD->getDependency(C);
|
||||
|
||||
if (local_dep == MemoryDependenceAnalysis::None) {
|
||||
if (local_dep.getInt() == MemoryDependenceAnalysis::None) {
|
||||
valueNumbering.insert(std::make_pair(V, nextValueNumber));
|
||||
return nextValueNumber++;
|
||||
} else if (local_dep != MemoryDependenceAnalysis::NonLocal) {
|
||||
if (!isa<CallInst>(local_dep)) {
|
||||
} else if (local_dep.getInt() != MemoryDependenceAnalysis::NonLocal) {
|
||||
// FIXME: INDENT PROPERLY!
|
||||
if (!isa<CallInst>(local_dep.getPointer())) {
|
||||
valueNumbering.insert(std::make_pair(V, nextValueNumber));
|
||||
return nextValueNumber++;
|
||||
}
|
||||
|
||||
CallInst* local_cdep = cast<CallInst>(local_dep);
|
||||
CallInst* local_cdep = cast<CallInst>(local_dep.getPointer());
|
||||
|
||||
// FIXME: INDENT PROPERLY.
|
||||
if (local_cdep->getCalledFunction() != C->getCalledFunction() ||
|
||||
local_cdep->getNumOperands() != C->getNumOperands()) {
|
||||
valueNumbering.insert(std::make_pair(V, nextValueNumber));
|
||||
@ -493,19 +495,20 @@ uint32_t ValueTable::lookup_or_add(Value* V) {
|
||||
}
|
||||
|
||||
|
||||
DenseMap<BasicBlock*, Value*> deps;
|
||||
DenseMap<BasicBlock*, MemoryDependenceAnalysis::DepResultTy> deps;
|
||||
MD->getNonLocalDependency(C, deps);
|
||||
CallInst* cdep = 0;
|
||||
|
||||
for (DenseMap<BasicBlock*, Value*>::iterator I = deps.begin(),
|
||||
E = deps.end(); I != E; ++I) {
|
||||
if (I->second == MemoryDependenceAnalysis::None) {
|
||||
for (DenseMap<BasicBlock*, MemoryDependenceAnalysis::DepResultTy>
|
||||
::iterator I = deps.begin(), E = deps.end(); I != E; ++I) {
|
||||
if (I->second.getInt() == MemoryDependenceAnalysis::None) {
|
||||
valueNumbering.insert(std::make_pair(V, nextValueNumber));
|
||||
|
||||
return nextValueNumber++;
|
||||
} else if (I->second != MemoryDependenceAnalysis::NonLocal) {
|
||||
} else if (I->second.getInt() != MemoryDependenceAnalysis::NonLocal) {
|
||||
// FIXME: INDENT PROPERLY
|
||||
if (DT->properlyDominates(I->first, C->getParent())) {
|
||||
if (CallInst* CD = dyn_cast<CallInst>(I->second))
|
||||
if (CallInst* CD = dyn_cast<CallInst>(I->second.getPointer()))
|
||||
cdep = CD;
|
||||
else {
|
||||
valueNumbering.insert(std::make_pair(V, nextValueNumber));
|
||||
@ -718,6 +721,8 @@ namespace {
|
||||
AU.addPreserved<AliasAnalysis>();
|
||||
}
|
||||
|
||||
typedef MemoryDependenceAnalysis::DepResultTy DepResultTy;
|
||||
|
||||
// Helper fuctions
|
||||
// FIXME: eliminate or document these better
|
||||
bool processLoad(LoadInst* L,
|
||||
@ -861,7 +866,7 @@ bool GVN::processNonLocalLoad(LoadInst* L,
|
||||
MemoryDependenceAnalysis& MD = getAnalysis<MemoryDependenceAnalysis>();
|
||||
|
||||
// Find the non-local dependencies of the load
|
||||
DenseMap<BasicBlock*, Value*> deps;
|
||||
DenseMap<BasicBlock*, DepResultTy> deps;
|
||||
MD.getNonLocalDependency(L, deps);
|
||||
|
||||
// If we had to process more than one hundred blocks to find the
|
||||
@ -873,19 +878,19 @@ bool GVN::processNonLocalLoad(LoadInst* L,
|
||||
DenseMap<BasicBlock*, Value*> repl;
|
||||
|
||||
// Filter out useless results (non-locals, etc)
|
||||
for (DenseMap<BasicBlock*, Value*>::iterator I = deps.begin(), E = deps.end();
|
||||
I != E; ++I) {
|
||||
if (I->second == MemoryDependenceAnalysis::None)
|
||||
for (DenseMap<BasicBlock*, DepResultTy>::iterator I = deps.begin(),
|
||||
E = deps.end(); I != E; ++I) {
|
||||
if (I->second.getInt() == MemoryDependenceAnalysis::None)
|
||||
return false;
|
||||
|
||||
if (I->second == MemoryDependenceAnalysis::NonLocal)
|
||||
if (I->second.getInt() == MemoryDependenceAnalysis::NonLocal)
|
||||
continue;
|
||||
|
||||
if (StoreInst* S = dyn_cast<StoreInst>(I->second)) {
|
||||
if (StoreInst* S = dyn_cast<StoreInst>(I->second.getPointer())) {
|
||||
if (S->getPointerOperand() != L->getPointerOperand())
|
||||
return false;
|
||||
repl[I->first] = S->getOperand(0);
|
||||
} else if (LoadInst* LD = dyn_cast<LoadInst>(I->second)) {
|
||||
} else if (LoadInst* LD = dyn_cast<LoadInst>(I->second.getPointer())) {
|
||||
if (LD->getPointerOperand() != L->getPointerOperand())
|
||||
return false;
|
||||
repl[I->first] = LD;
|
||||
@ -936,8 +941,8 @@ bool GVN::processLoad(LoadInst *L, DenseMap<Value*, LoadInst*> &lastLoad,
|
||||
// ... to a pointer that has been loaded from before...
|
||||
MemoryDependenceAnalysis& MD = getAnalysis<MemoryDependenceAnalysis>();
|
||||
bool removedNonLocal = false;
|
||||
Instruction* dep = MD.getDependency(L);
|
||||
if (dep == MemoryDependenceAnalysis::NonLocal &&
|
||||
DepResultTy dep = MD.getDependency(L);
|
||||
if (dep.getInt() == MemoryDependenceAnalysis::NonLocal &&
|
||||
L->getParent() != &L->getParent()->getParent()->getEntryBlock()) {
|
||||
removedNonLocal = processNonLocalLoad(L, toErase);
|
||||
|
||||
@ -952,11 +957,10 @@ bool GVN::processLoad(LoadInst *L, DenseMap<Value*, LoadInst*> &lastLoad,
|
||||
|
||||
// Walk up the dependency chain until we either find
|
||||
// a dependency we can use, or we can't walk any further
|
||||
while (dep != MemoryDependenceAnalysis::None &&
|
||||
dep != MemoryDependenceAnalysis::NonLocal &&
|
||||
(isa<LoadInst>(dep) || isa<StoreInst>(dep))) {
|
||||
while (dep.getInt() == MemoryDependenceAnalysis::Normal &&
|
||||
(isa<LoadInst>(dep.getPointer()) || isa<StoreInst>(dep.getPointer()))){
|
||||
// ... that depends on a store ...
|
||||
if (StoreInst* S = dyn_cast<StoreInst>(dep)) {
|
||||
if (StoreInst* S = dyn_cast<StoreInst>(dep.getPointer())) {
|
||||
if (S->getPointerOperand() == pointer) {
|
||||
// Remove it!
|
||||
MD.removeInstruction(L);
|
||||
@ -974,7 +978,7 @@ bool GVN::processLoad(LoadInst *L, DenseMap<Value*, LoadInst*> &lastLoad,
|
||||
// If we don't depend on a store, and we haven't
|
||||
// been loaded before, bail.
|
||||
break;
|
||||
} else if (dep == last) {
|
||||
} else if (dep.getPointer() == last) {
|
||||
// Remove it!
|
||||
MD.removeInstruction(L);
|
||||
|
||||
@ -985,16 +989,15 @@ bool GVN::processLoad(LoadInst *L, DenseMap<Value*, LoadInst*> &lastLoad,
|
||||
|
||||
break;
|
||||
} else {
|
||||
dep = MD.getDependency(L, dep);
|
||||
dep = MD.getDependency(L, dep.getPointer());
|
||||
}
|
||||
}
|
||||
|
||||
if (dep != MemoryDependenceAnalysis::None &&
|
||||
dep != MemoryDependenceAnalysis::NonLocal &&
|
||||
isa<AllocationInst>(dep)) {
|
||||
if (dep.getInt() == MemoryDependenceAnalysis::Normal &&
|
||||
isa<AllocationInst>(dep.getPointer())) {
|
||||
// Check that this load is actually from the
|
||||
// allocation we found
|
||||
if (L->getOperand(0)->getUnderlyingObject() == dep) {
|
||||
if (L->getOperand(0)->getUnderlyingObject() == dep.getPointer()) {
|
||||
// If this load depends directly on an allocation, there isn't
|
||||
// anything stored there; therefore, we can optimize this load
|
||||
// to undef.
|
||||
|
@ -629,18 +629,18 @@ bool MemCpyOpt::processMemCpy(MemCpyInst* M) {
|
||||
// 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
|
||||
Instruction* dep = MD.getDependency(M);
|
||||
if (dep == MemoryDependenceAnalysis::None ||
|
||||
dep == MemoryDependenceAnalysis::NonLocal)
|
||||
MemoryDependenceAnalysis::DepResultTy dep = MD.getDependency(M);
|
||||
if (dep.getInt() == MemoryDependenceAnalysis::None ||
|
||||
dep.getInt() == MemoryDependenceAnalysis::NonLocal)
|
||||
return false;
|
||||
else if (!isa<MemCpyInst>(dep)) {
|
||||
if (CallInst* C = dyn_cast<CallInst>(dep))
|
||||
else if (!isa<MemCpyInst>(dep.getPointer())) {
|
||||
if (CallInst* C = dyn_cast<CallInst>(dep.getPointer()))
|
||||
return performCallSlotOptzn(M, C);
|
||||
else
|
||||
return false;
|
||||
}
|
||||
|
||||
MemCpyInst* MDep = cast<MemCpyInst>(dep);
|
||||
MemCpyInst* MDep = cast<MemCpyInst>(dep.getPointer());
|
||||
|
||||
// We can only transforms memcpy's where the dest of one is the source of the
|
||||
// other
|
||||
@ -691,7 +691,7 @@ bool MemCpyOpt::processMemCpy(MemCpyInst* M) {
|
||||
|
||||
// If C and M don't interfere, then this is a valid transformation. If they
|
||||
// did, this would mean that the two sources overlap, which would be bad.
|
||||
if (MD.getDependency(C) == MDep) {
|
||||
if (MD.getDependency(C) == dep) {
|
||||
MD.dropInstruction(M);
|
||||
M->eraseFromParent();
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user