-//===- MemoryDependenceAnalysis.cpp - Mem Deps Implementation --*- C++ -*-===//
+//===- MemoryDependenceAnalysis.cpp - Mem Deps Implementation -------------===//
//
// The LLVM Compiler Infrastructure
//
//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "memdep"
#include "llvm/Analysis/MemoryDependenceAnalysis.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/PHITransAddr.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/PredIteratorCache.h"
#include "llvm/Support/Debug.h"
-#include "llvm/Support/PredIteratorCache.h"
using namespace llvm;
+#define DEBUG_TYPE "memdep"
+
STATISTIC(NumCacheNonLocal, "Number of fully cached non-local responses");
STATISTIC(NumCacheDirtyNonLocal, "Number of dirty cached non-local responses");
STATISTIC(NumUncacheNonLocal, "Number of uncached non-local responses");
"Number of block queries that were completely cached");
// Limit for the number of instructions to scan in a block.
-// FIXME: Figure out what a sane value is for this.
-// (500 is relatively insane.)
-static const int BlockScanLimit = 500;
+static const int BlockScanLimit = 100;
char MemoryDependenceAnalysis::ID = 0;
"Memory Dependence Analysis", false, true)
MemoryDependenceAnalysis::MemoryDependenceAnalysis()
-: FunctionPass(ID), PredCache(0) {
+ : FunctionPass(ID), PredCache() {
initializeMemoryDependenceAnalysisPass(*PassRegistry::getPassRegistry());
}
MemoryDependenceAnalysis::~MemoryDependenceAnalysis() {
bool MemoryDependenceAnalysis::runOnFunction(Function &) {
AA = &getAnalysis<AliasAnalysis>();
- TD = getAnalysisIfAvailable<DataLayout>();
- DT = getAnalysisIfAvailable<DominatorTree>();
- if (PredCache == 0)
+ DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
+ DL = DLP ? &DLP->getDataLayout() : nullptr;
+ DominatorTreeWrapperPass *DTWP =
+ getAnalysisIfAvailable<DominatorTreeWrapperPass>();
+ DT = DTWP ? &DTWP->getDomTree() : nullptr;
+ if (!PredCache)
PredCache.reset(new PredIteratorCache());
return false;
}
if (LI->isUnordered()) {
Loc = AA->getLocation(LI);
return AliasAnalysis::Ref;
- } else if (LI->getOrdering() == Monotonic) {
+ }
+ if (LI->getOrdering() == Monotonic) {
Loc = AA->getLocation(LI);
return AliasAnalysis::ModRef;
}
if (SI->isUnordered()) {
Loc = AA->getLocation(SI);
return AliasAnalysis::Mod;
- } else if (SI->getOrdering() == Monotonic) {
+ }
+ if (SI->getOrdering() == Monotonic) {
Loc = AA->getLocation(SI);
return AliasAnalysis::ModRef;
}
const Value *&MemLocBase,
int64_t &MemLocOffs,
const LoadInst *LI,
- const DataLayout *TD) {
+ const DataLayout *DL) {
// If we have no target data, we can't do this.
- if (TD == 0) return false;
+ if (!DL) return false;
// If we haven't already computed the base/offset of MemLoc, do so now.
- if (MemLocBase == 0)
- MemLocBase = GetPointerBaseWithConstantOffset(MemLoc.Ptr, MemLocOffs, TD);
+ if (!MemLocBase)
+ MemLocBase = GetPointerBaseWithConstantOffset(MemLoc.Ptr, MemLocOffs, DL);
unsigned Size = MemoryDependenceAnalysis::
getLoadLoadClobberFullWidthSize(MemLocBase, MemLocOffs, MemLoc.Size,
- LI, *TD);
+ LI, *DL);
return Size != 0;
}
unsigned MemoryDependenceAnalysis::
getLoadLoadClobberFullWidthSize(const Value *MemLocBase, int64_t MemLocOffs,
unsigned MemLocSize, const LoadInst *LI,
- const DataLayout &TD) {
+ const DataLayout &DL) {
// We can only extend simple integer loads.
if (!isa<IntegerType>(LI->getType()) || !LI->isSimple()) return 0;
// Get the base of this load.
int64_t LIOffs = 0;
const Value *LIBase =
- GetPointerBaseWithConstantOffset(LI->getPointerOperand(), LIOffs, &TD);
+ GetPointerBaseWithConstantOffset(LI->getPointerOperand(), LIOffs, &DL);
// If the two pointers are not based on the same pointer, we can't tell that
// they are related.
// If this load size is bigger than our known alignment or would not fit
// into a native integer register, then we fail.
if (NewLoadByteSize > LoadAlign ||
- !TD.fitsInLegalInteger(NewLoadByteSize*8))
+ !DL.fitsInLegalInteger(NewLoadByteSize*8))
return 0;
if (LIOffs+NewLoadByteSize > MemLocEnd &&
BasicBlock::iterator ScanIt, BasicBlock *BB,
Instruction *QueryInst) {
- const Value *MemLocBase = 0;
+ const Value *MemLocBase = nullptr;
int64_t MemLocOffset = 0;
unsigned Limit = BlockScanLimit;
bool isInvariantLoad = false;
if (isLoad && QueryInst) {
LoadInst *LI = dyn_cast<LoadInst>(QueryInst);
- if (LI && LI->getMetadata(LLVMContext::MD_invariant_load) != 0)
+ if (LI && LI->getMetadata(LLVMContext::MD_invariant_load) != nullptr)
isInvariantLoad = true;
}
// Walk backwards through the basic block, looking for dependencies.
while (ScanIt != BB->begin()) {
+ Instruction *Inst = --ScanIt;
+
+ if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Inst))
+ // Debug intrinsics don't (and can't) cause dependencies.
+ if (isa<DbgInfoIntrinsic>(II)) continue;
+
// Limit the amount of scanning we do so we don't end up with quadratic
// running time on extreme testcases.
--Limit;
if (!Limit)
return MemDepResult::getUnknown();
- Instruction *Inst = --ScanIt;
-
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Inst)) {
- // Debug intrinsics don't (and can't) cause dependences.
- if (isa<DbgInfoIntrinsic>(II)) continue;
-
// If we reach a lifetime begin or end marker, then the query ends here
// because the value is undefined.
if (II->getIntrinsicID() == Intrinsic::lifetime_start) {
if (IntegerType *ITy = dyn_cast<IntegerType>(LI->getType()))
if (LI->getAlignment()*8 > ITy->getPrimitiveSizeInBits() &&
isLoadLoadClobberIfExtendedToFullWidth(MemLoc, MemLocBase,
- MemLocOffset, LI, TD))
+ MemLocOffset, LI, DL))
return MemDepResult::getClobber(Inst);
continue;
// need to continue scanning until the malloc call.
const TargetLibraryInfo *TLI = AA->getTargetLibraryInfo();
if (isa<AllocaInst>(Inst) || isNoAliasFn(Inst, TLI)) {
- const Value *AccessPtr = GetUnderlyingObject(MemLoc.Ptr, TD);
+ const Value *AccessPtr = GetUnderlyingObject(MemLoc.Ptr, DL);
if (AccessPtr == Inst || AA->isMustAlias(Inst, AccessPtr))
return MemDepResult::getDef(Inst);
NonLocalDepInfo::iterator Entry =
std::upper_bound(Cache.begin(), Cache.begin()+NumSortedEntries,
NonLocalDepEntry(DirtyBB));
- if (Entry != Cache.begin() && prior(Entry)->getBB() == DirtyBB)
+ if (Entry != Cache.begin() && std::prev(Entry)->getBB() == DirtyBB)
--Entry;
- NonLocalDepEntry *ExistingResult = 0;
+ NonLocalDepEntry *ExistingResult = nullptr;
if (Entry != Cache.begin()+NumSortedEntries &&
Entry->getBB() == DirtyBB) {
// If we already have an entry, and if it isn't already dirty, the block
"Can't get pointer deps of a non-pointer!");
Result.clear();
- PHITransAddr Address(const_cast<Value *>(Loc.Ptr), TD);
+ PHITransAddr Address(const_cast<Value *>(Loc.Ptr), DL);
// This is the set of blocks we've inspected, and the pointer we consider in
// each block. Because of critical edges, we currently bail out if querying
if (Entry != Cache->begin() && (Entry-1)->getBB() == BB)
--Entry;
- NonLocalDepEntry *ExistingResult = 0;
+ NonLocalDepEntry *ExistingResult = nullptr;
if (Entry != Cache->begin()+NumSortedEntries && Entry->getBB() == BB)
ExistingResult = &*Entry;
SmallVectorImpl<NonLocalDepResult> &Result,
DenseMap<BasicBlock*, Value*> &Visited,
bool SkipFirstBlock) {
-
// Look up the cached info for Pointer.
ValueIsLoadPair CacheKey(Pointer.getAddr(), isLoad);
if (CacheInfo->TBAATag != Loc.TBAATag) {
if (CacheInfo->TBAATag) {
CacheInfo->Pair = BBSkipFirstBlockPair();
- CacheInfo->TBAATag = 0;
+ CacheInfo->TBAATag = nullptr;
for (NonLocalDepInfo::iterator DI = CacheInfo->NonLocalDeps.begin(),
DE = CacheInfo->NonLocalDeps.end(); DI != DE; ++DI)
if (Instruction *Inst = DI->getResult().getInst())
for (NonLocalDepInfo::iterator I = Cache->begin(), E = Cache->end();
I != E; ++I) {
Visited.insert(std::make_pair(I->getBB(), Addr));
- if (!I->getResult().isNonLocal() && DT->isReachableFromEntry(I->getBB()))
+ if (I->getResult().isNonLocal()) {
+ continue;
+ }
+
+ if (!DT) {
+ Result.push_back(NonLocalDepResult(I->getBB(),
+ MemDepResult::getUnknown(),
+ Addr));
+ } else if (DT->isReachableFromEntry(I->getBB())) {
Result.push_back(NonLocalDepResult(I->getBB(), I->getResult(), Addr));
+ }
}
++NumCacheCompleteNonLocalPtr;
return false;
NumSortedEntries);
// If we got a Def or Clobber, add this to the list of results.
- if (!Dep.isNonLocal() && DT->isReachableFromEntry(BB)) {
- Result.push_back(NonLocalDepResult(BB, Dep, Pointer.getAddr()));
- continue;
+ if (!Dep.isNonLocal()) {
+ if (!DT) {
+ Result.push_back(NonLocalDepResult(BB,
+ MemDepResult::getUnknown(),
+ Pointer.getAddr()));
+ continue;
+ } else if (DT->isReachableFromEntry(BB)) {
+ Result.push_back(NonLocalDepResult(BB, Dep, Pointer.getAddr()));
+ continue;
+ }
}
}
SortNonLocalDepInfoCache(*Cache, NumSortedEntries);
NumSortedEntries = Cache->size();
}
- Cache = 0;
+ Cache = nullptr;
PredList.clear();
for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI) {
// Get the PHI translated pointer in this predecessor. This can fail if
// not translatable, in which case the getAddr() returns null.
PHITransAddr &PredPointer = PredList.back().second;
- PredPointer.PHITranslateValue(BB, Pred, 0);
+ PredPointer.PHITranslateValue(BB, Pred, nullptr);
Value *PredPtrVal = PredPointer.getAddr();
// Make sure to clean up the Visited map before continuing on to
// PredTranslationFailure.
- for (unsigned i = 0; i < PredList.size(); i++)
+ for (unsigned i = 0, n = PredList.size(); i < n; ++i)
Visited.erase(PredList[i].first);
goto PredTranslationFailure;
// any results for. (getNonLocalPointerDepFromBB will modify our
// datastructures in ways the code after the PredTranslationFailure label
// doesn't expect.)
- for (unsigned i = 0; i < PredList.size(); i++) {
+ for (unsigned i = 0, n = PredList.size(); i < n; ++i) {
BasicBlock *Pred = PredList[i].first;
PHITransAddr &PredPointer = PredList[i].second;
Value *PredPtrVal = PredPointer.getAddr();
// predecessor, then we have to assume that the pointer is clobbered in
// that predecessor. We can still do PRE of the load, which would insert
// a computation of the pointer in this predecessor.
- if (PredPtrVal == 0)
+ if (!PredPtrVal)
CanTranslate = false;
// FIXME: it is entirely possible that PHI translating will end up with
// for the given block. It assumes that we haven't modified any of
// our datastructures while processing the current block.
- if (Cache == 0) {
+ if (!Cache) {
// Refresh the CacheInfo/Cache pointer if it got invalidated.
CacheInfo = &NonLocalPointerDeps[CacheKey];
Cache = &CacheInfo->NonLocalDeps;
for (unsigned i = 0, e = PInfo.size(); i != e; ++i) {
Instruction *Target = PInfo[i].getResult().getInst();
- if (Target == 0) continue; // Ignore non-local dep results.
+ if (!Target) continue; // Ignore non-local dep results.
assert(Target->getParent() == PInfo[i].getBB());
// Eliminating the dirty entry from 'Cache', so update the reverse info.
projects / oota-llvm.git / blobdiff