forked from OSchip/llvm-project
776 lines
26 KiB
C++
776 lines
26 KiB
C++
//===- AliasSetTracker.cpp - Alias Sets Tracker implementation-------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the AliasSetTracker and AliasSet classes.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/Analysis/AliasSetTracker.h"
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#include "llvm/Analysis/AliasAnalysis.h"
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#include "llvm/Analysis/GuardUtils.h"
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#include "llvm/Analysis/LoopInfo.h"
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#include "llvm/Analysis/MemoryLocation.h"
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#include "llvm/Config/llvm-config.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/Function.h"
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#include "llvm/IR/InstIterator.h"
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#include "llvm/IR/Instructions.h"
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#include "llvm/IR/IntrinsicInst.h"
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#include "llvm/IR/Module.h"
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#include "llvm/IR/PassManager.h"
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#include "llvm/IR/PatternMatch.h"
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#include "llvm/IR/Value.h"
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#include "llvm/InitializePasses.h"
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#include "llvm/Pass.h"
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#include "llvm/Support/AtomicOrdering.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/Compiler.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/raw_ostream.h"
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using namespace llvm;
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static cl::opt<unsigned>
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SaturationThreshold("alias-set-saturation-threshold", cl::Hidden,
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cl::init(250),
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cl::desc("The maximum number of pointers may-alias "
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"sets may contain before degradation"));
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/// mergeSetIn - Merge the specified alias set into this alias set.
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///
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void AliasSet::mergeSetIn(AliasSet &AS, AliasSetTracker &AST) {
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assert(!AS.Forward && "Alias set is already forwarding!");
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assert(!Forward && "This set is a forwarding set!!");
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bool WasMustAlias = (Alias == SetMustAlias);
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// Update the alias and access types of this set...
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Access |= AS.Access;
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Alias |= AS.Alias;
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if (Alias == SetMustAlias) {
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// Check that these two merged sets really are must aliases. Since both
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// used to be must-alias sets, we can just check any pointer from each set
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// for aliasing.
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AliasAnalysis &AA = AST.getAliasAnalysis();
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PointerRec *L = getSomePointer();
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PointerRec *R = AS.getSomePointer();
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// If the pointers are not a must-alias pair, this set becomes a may alias.
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if (!AA.isMustAlias(
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MemoryLocation(L->getValue(), L->getSize(), L->getAAInfo()),
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MemoryLocation(R->getValue(), R->getSize(), R->getAAInfo())))
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Alias = SetMayAlias;
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}
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if (Alias == SetMayAlias) {
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if (WasMustAlias)
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AST.TotalMayAliasSetSize += size();
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if (AS.Alias == SetMustAlias)
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AST.TotalMayAliasSetSize += AS.size();
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}
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bool ASHadUnknownInsts = !AS.UnknownInsts.empty();
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if (UnknownInsts.empty()) { // Merge call sites...
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if (ASHadUnknownInsts) {
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std::swap(UnknownInsts, AS.UnknownInsts);
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addRef();
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}
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} else if (ASHadUnknownInsts) {
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llvm::append_range(UnknownInsts, AS.UnknownInsts);
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AS.UnknownInsts.clear();
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}
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AS.Forward = this; // Forward across AS now...
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addRef(); // AS is now pointing to us...
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// Merge the list of constituent pointers...
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if (AS.PtrList) {
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SetSize += AS.size();
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AS.SetSize = 0;
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*PtrListEnd = AS.PtrList;
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AS.PtrList->setPrevInList(PtrListEnd);
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PtrListEnd = AS.PtrListEnd;
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AS.PtrList = nullptr;
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AS.PtrListEnd = &AS.PtrList;
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assert(*AS.PtrListEnd == nullptr && "End of list is not null?");
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}
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if (ASHadUnknownInsts)
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AS.dropRef(AST);
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}
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void AliasSetTracker::removeAliasSet(AliasSet *AS) {
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if (AliasSet *Fwd = AS->Forward) {
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Fwd->dropRef(*this);
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AS->Forward = nullptr;
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} else // Update TotalMayAliasSetSize only if not forwarding.
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if (AS->Alias == AliasSet::SetMayAlias)
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TotalMayAliasSetSize -= AS->size();
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AliasSets.erase(AS);
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// If we've removed the saturated alias set, set saturated marker back to
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// nullptr and ensure this tracker is empty.
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if (AS == AliasAnyAS) {
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AliasAnyAS = nullptr;
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assert(AliasSets.empty() && "Tracker not empty");
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}
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}
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void AliasSet::removeFromTracker(AliasSetTracker &AST) {
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assert(RefCount == 0 && "Cannot remove non-dead alias set from tracker!");
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AST.removeAliasSet(this);
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}
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void AliasSet::addPointer(AliasSetTracker &AST, PointerRec &Entry,
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LocationSize Size, const AAMDNodes &AAInfo,
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bool KnownMustAlias, bool SkipSizeUpdate) {
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assert(!Entry.hasAliasSet() && "Entry already in set!");
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// Check to see if we have to downgrade to _may_ alias.
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if (isMustAlias())
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if (PointerRec *P = getSomePointer()) {
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if (!KnownMustAlias) {
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AliasAnalysis &AA = AST.getAliasAnalysis();
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AliasResult Result = AA.alias(
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MemoryLocation(P->getValue(), P->getSize(), P->getAAInfo()),
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MemoryLocation(Entry.getValue(), Size, AAInfo));
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if (Result != AliasResult::MustAlias) {
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Alias = SetMayAlias;
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AST.TotalMayAliasSetSize += size();
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}
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assert(Result != AliasResult::NoAlias && "Cannot be part of must set!");
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} else if (!SkipSizeUpdate)
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P->updateSizeAndAAInfo(Size, AAInfo);
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}
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Entry.setAliasSet(this);
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Entry.updateSizeAndAAInfo(Size, AAInfo);
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// Add it to the end of the list...
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++SetSize;
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assert(*PtrListEnd == nullptr && "End of list is not null?");
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*PtrListEnd = &Entry;
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PtrListEnd = Entry.setPrevInList(PtrListEnd);
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assert(*PtrListEnd == nullptr && "End of list is not null?");
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// Entry points to alias set.
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addRef();
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if (Alias == SetMayAlias)
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AST.TotalMayAliasSetSize++;
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}
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void AliasSet::addUnknownInst(Instruction *I, AliasAnalysis &AA) {
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if (UnknownInsts.empty())
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addRef();
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UnknownInsts.emplace_back(I);
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// Guards are marked as modifying memory for control flow modelling purposes,
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// but don't actually modify any specific memory location.
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using namespace PatternMatch;
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bool MayWriteMemory = I->mayWriteToMemory() && !isGuard(I) &&
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!(I->use_empty() && match(I, m_Intrinsic<Intrinsic::invariant_start>()));
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if (!MayWriteMemory) {
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Alias = SetMayAlias;
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Access |= RefAccess;
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return;
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}
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// FIXME: This should use mod/ref information to make this not suck so bad
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Alias = SetMayAlias;
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Access = ModRefAccess;
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}
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/// aliasesPointer - If the specified pointer "may" (or must) alias one of the
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/// members in the set return the appropriate AliasResult. Otherwise return
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/// NoAlias.
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///
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AliasResult AliasSet::aliasesPointer(const Value *Ptr, LocationSize Size,
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const AAMDNodes &AAInfo,
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AliasAnalysis &AA) const {
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if (AliasAny)
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return AliasResult::MayAlias;
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if (Alias == SetMustAlias) {
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assert(UnknownInsts.empty() && "Illegal must alias set!");
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// If this is a set of MustAliases, only check to see if the pointer aliases
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// SOME value in the set.
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PointerRec *SomePtr = getSomePointer();
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assert(SomePtr && "Empty must-alias set??");
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return AA.alias(MemoryLocation(SomePtr->getValue(), SomePtr->getSize(),
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SomePtr->getAAInfo()),
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MemoryLocation(Ptr, Size, AAInfo));
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}
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// If this is a may-alias set, we have to check all of the pointers in the set
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// to be sure it doesn't alias the set...
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for (iterator I = begin(), E = end(); I != E; ++I) {
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AliasResult AR =
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AA.alias(MemoryLocation(Ptr, Size, AAInfo),
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MemoryLocation(I.getPointer(), I.getSize(), I.getAAInfo()));
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if (AR != AliasResult::NoAlias)
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return AR;
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}
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// Check the unknown instructions...
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if (!UnknownInsts.empty()) {
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for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i)
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if (auto *Inst = getUnknownInst(i))
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if (isModOrRefSet(
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AA.getModRefInfo(Inst, MemoryLocation(Ptr, Size, AAInfo))))
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return AliasResult::MayAlias;
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}
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return AliasResult::NoAlias;
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}
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bool AliasSet::aliasesUnknownInst(const Instruction *Inst,
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AliasAnalysis &AA) const {
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if (AliasAny)
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return true;
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assert(Inst->mayReadOrWriteMemory() &&
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"Instruction must either read or write memory.");
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for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i) {
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if (auto *UnknownInst = getUnknownInst(i)) {
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const auto *C1 = dyn_cast<CallBase>(UnknownInst);
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const auto *C2 = dyn_cast<CallBase>(Inst);
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if (!C1 || !C2 || isModOrRefSet(AA.getModRefInfo(C1, C2)) ||
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isModOrRefSet(AA.getModRefInfo(C2, C1)))
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return true;
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}
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}
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for (iterator I = begin(), E = end(); I != E; ++I)
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if (isModOrRefSet(AA.getModRefInfo(
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Inst, MemoryLocation(I.getPointer(), I.getSize(), I.getAAInfo()))))
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return true;
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return false;
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}
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Instruction* AliasSet::getUniqueInstruction() {
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if (AliasAny)
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// May have collapses alias set
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return nullptr;
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if (begin() != end()) {
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if (!UnknownInsts.empty())
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// Another instruction found
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return nullptr;
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if (std::next(begin()) != end())
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// Another instruction found
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return nullptr;
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Value *Addr = begin()->getValue();
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assert(!Addr->user_empty() &&
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"where's the instruction which added this pointer?");
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if (std::next(Addr->user_begin()) != Addr->user_end())
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// Another instruction found -- this is really restrictive
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// TODO: generalize!
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return nullptr;
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return cast<Instruction>(*(Addr->user_begin()));
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}
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if (1 != UnknownInsts.size())
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return nullptr;
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return cast<Instruction>(UnknownInsts[0]);
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}
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void AliasSetTracker::clear() {
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// Delete all the PointerRec entries.
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for (auto &I : PointerMap)
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I.second->eraseFromList();
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PointerMap.clear();
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// The alias sets should all be clear now.
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AliasSets.clear();
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}
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/// mergeAliasSetsForPointer - Given a pointer, merge all alias sets that may
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/// alias the pointer. Return the unified set, or nullptr if no set that aliases
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/// the pointer was found. MustAliasAll is updated to true/false if the pointer
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/// is found to MustAlias all the sets it merged.
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AliasSet *AliasSetTracker::mergeAliasSetsForPointer(const Value *Ptr,
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LocationSize Size,
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const AAMDNodes &AAInfo,
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bool &MustAliasAll) {
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AliasSet *FoundSet = nullptr;
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MustAliasAll = true;
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for (AliasSet &AS : llvm::make_early_inc_range(*this)) {
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if (AS.Forward)
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continue;
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AliasResult AR = AS.aliasesPointer(Ptr, Size, AAInfo, AA);
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if (AR == AliasResult::NoAlias)
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continue;
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if (AR != AliasResult::MustAlias)
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MustAliasAll = false;
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if (!FoundSet) {
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// If this is the first alias set ptr can go into, remember it.
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FoundSet = &AS;
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} else {
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// Otherwise, we must merge the sets.
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FoundSet->mergeSetIn(AS, *this);
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}
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}
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return FoundSet;
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}
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AliasSet *AliasSetTracker::findAliasSetForUnknownInst(Instruction *Inst) {
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AliasSet *FoundSet = nullptr;
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for (AliasSet &AS : llvm::make_early_inc_range(*this)) {
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if (AS.Forward || !AS.aliasesUnknownInst(Inst, AA))
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continue;
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if (!FoundSet) {
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// If this is the first alias set ptr can go into, remember it.
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FoundSet = &AS;
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} else {
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// Otherwise, we must merge the sets.
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FoundSet->mergeSetIn(AS, *this);
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}
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}
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return FoundSet;
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}
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AliasSet &AliasSetTracker::getAliasSetFor(const MemoryLocation &MemLoc) {
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Value * const Pointer = const_cast<Value*>(MemLoc.Ptr);
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const LocationSize Size = MemLoc.Size;
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const AAMDNodes &AAInfo = MemLoc.AATags;
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AliasSet::PointerRec &Entry = getEntryFor(Pointer);
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if (AliasAnyAS) {
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// At this point, the AST is saturated, so we only have one active alias
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// set. That means we already know which alias set we want to return, and
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// just need to add the pointer to that set to keep the data structure
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// consistent.
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// This, of course, means that we will never need a merge here.
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if (Entry.hasAliasSet()) {
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Entry.updateSizeAndAAInfo(Size, AAInfo);
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assert(Entry.getAliasSet(*this) == AliasAnyAS &&
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"Entry in saturated AST must belong to only alias set");
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} else {
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AliasAnyAS->addPointer(*this, Entry, Size, AAInfo);
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}
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return *AliasAnyAS;
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}
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bool MustAliasAll = false;
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// Check to see if the pointer is already known.
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if (Entry.hasAliasSet()) {
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// If the size changed, we may need to merge several alias sets.
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// Note that we can *not* return the result of mergeAliasSetsForPointer
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// due to a quirk of alias analysis behavior. Since alias(undef, undef)
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// is NoAlias, mergeAliasSetsForPointer(undef, ...) will not find the
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// the right set for undef, even if it exists.
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if (Entry.updateSizeAndAAInfo(Size, AAInfo))
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mergeAliasSetsForPointer(Pointer, Size, AAInfo, MustAliasAll);
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// Return the set!
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return *Entry.getAliasSet(*this)->getForwardedTarget(*this);
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}
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if (AliasSet *AS =
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mergeAliasSetsForPointer(Pointer, Size, AAInfo, MustAliasAll)) {
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// Add it to the alias set it aliases.
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AS->addPointer(*this, Entry, Size, AAInfo, MustAliasAll);
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return *AS;
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}
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// Otherwise create a new alias set to hold the loaded pointer.
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AliasSets.push_back(new AliasSet());
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AliasSets.back().addPointer(*this, Entry, Size, AAInfo, true);
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return AliasSets.back();
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}
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void AliasSetTracker::add(Value *Ptr, LocationSize Size,
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const AAMDNodes &AAInfo) {
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addPointer(MemoryLocation(Ptr, Size, AAInfo), AliasSet::NoAccess);
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}
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void AliasSetTracker::add(LoadInst *LI) {
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if (isStrongerThanMonotonic(LI->getOrdering()))
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return addUnknown(LI);
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addPointer(MemoryLocation::get(LI), AliasSet::RefAccess);
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}
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void AliasSetTracker::add(StoreInst *SI) {
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if (isStrongerThanMonotonic(SI->getOrdering()))
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return addUnknown(SI);
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addPointer(MemoryLocation::get(SI), AliasSet::ModAccess);
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}
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void AliasSetTracker::add(VAArgInst *VAAI) {
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addPointer(MemoryLocation::get(VAAI), AliasSet::ModRefAccess);
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}
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void AliasSetTracker::add(AnyMemSetInst *MSI) {
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addPointer(MemoryLocation::getForDest(MSI), AliasSet::ModAccess);
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}
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void AliasSetTracker::add(AnyMemTransferInst *MTI) {
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addPointer(MemoryLocation::getForDest(MTI), AliasSet::ModAccess);
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addPointer(MemoryLocation::getForSource(MTI), AliasSet::RefAccess);
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}
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void AliasSetTracker::addUnknown(Instruction *Inst) {
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if (isa<DbgInfoIntrinsic>(Inst))
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return; // Ignore DbgInfo Intrinsics.
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if (auto *II = dyn_cast<IntrinsicInst>(Inst)) {
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// These intrinsics will show up as affecting memory, but they are just
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// markers.
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switch (II->getIntrinsicID()) {
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default:
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break;
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// FIXME: Add lifetime/invariant intrinsics (See: PR30807).
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case Intrinsic::assume:
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case Intrinsic::experimental_noalias_scope_decl:
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case Intrinsic::sideeffect:
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case Intrinsic::pseudoprobe:
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return;
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}
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}
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if (!Inst->mayReadOrWriteMemory())
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return; // doesn't alias anything
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if (AliasSet *AS = findAliasSetForUnknownInst(Inst)) {
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AS->addUnknownInst(Inst, AA);
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return;
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}
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AliasSets.push_back(new AliasSet());
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AliasSets.back().addUnknownInst(Inst, AA);
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}
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void AliasSetTracker::add(Instruction *I) {
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// Dispatch to one of the other add methods.
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if (LoadInst *LI = dyn_cast<LoadInst>(I))
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return add(LI);
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if (StoreInst *SI = dyn_cast<StoreInst>(I))
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return add(SI);
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if (VAArgInst *VAAI = dyn_cast<VAArgInst>(I))
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return add(VAAI);
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if (AnyMemSetInst *MSI = dyn_cast<AnyMemSetInst>(I))
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return add(MSI);
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if (AnyMemTransferInst *MTI = dyn_cast<AnyMemTransferInst>(I))
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return add(MTI);
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// Handle all calls with known mod/ref sets genericall
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if (auto *Call = dyn_cast<CallBase>(I))
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if (Call->onlyAccessesArgMemory()) {
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auto getAccessFromModRef = [](ModRefInfo MRI) {
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if (isRefSet(MRI) && isModSet(MRI))
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return AliasSet::ModRefAccess;
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else if (isModSet(MRI))
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return AliasSet::ModAccess;
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else if (isRefSet(MRI))
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return AliasSet::RefAccess;
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else
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return AliasSet::NoAccess;
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};
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ModRefInfo CallMask = createModRefInfo(AA.getModRefBehavior(Call));
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// Some intrinsics are marked as modifying memory for control flow
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// modelling purposes, but don't actually modify any specific memory
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// location.
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using namespace PatternMatch;
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if (Call->use_empty() &&
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match(Call, m_Intrinsic<Intrinsic::invariant_start>()))
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CallMask = clearMod(CallMask);
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for (auto IdxArgPair : enumerate(Call->args())) {
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int ArgIdx = IdxArgPair.index();
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const Value *Arg = IdxArgPair.value();
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if (!Arg->getType()->isPointerTy())
|
|
continue;
|
|
MemoryLocation ArgLoc =
|
|
MemoryLocation::getForArgument(Call, ArgIdx, nullptr);
|
|
ModRefInfo ArgMask = AA.getArgModRefInfo(Call, ArgIdx);
|
|
ArgMask = intersectModRef(CallMask, ArgMask);
|
|
if (!isNoModRef(ArgMask))
|
|
addPointer(ArgLoc, getAccessFromModRef(ArgMask));
|
|
}
|
|
return;
|
|
}
|
|
|
|
return addUnknown(I);
|
|
}
|
|
|
|
void AliasSetTracker::add(BasicBlock &BB) {
|
|
for (auto &I : BB)
|
|
add(&I);
|
|
}
|
|
|
|
void AliasSetTracker::add(const AliasSetTracker &AST) {
|
|
assert(&AA == &AST.AA &&
|
|
"Merging AliasSetTracker objects with different Alias Analyses!");
|
|
|
|
// Loop over all of the alias sets in AST, adding the pointers contained
|
|
// therein into the current alias sets. This can cause alias sets to be
|
|
// merged together in the current AST.
|
|
for (const AliasSet &AS : AST) {
|
|
if (AS.Forward)
|
|
continue; // Ignore forwarding alias sets
|
|
|
|
// If there are any call sites in the alias set, add them to this AST.
|
|
for (unsigned i = 0, e = AS.UnknownInsts.size(); i != e; ++i)
|
|
if (auto *Inst = AS.getUnknownInst(i))
|
|
add(Inst);
|
|
|
|
// Loop over all of the pointers in this alias set.
|
|
for (AliasSet::iterator ASI = AS.begin(), E = AS.end(); ASI != E; ++ASI)
|
|
addPointer(
|
|
MemoryLocation(ASI.getPointer(), ASI.getSize(), ASI.getAAInfo()),
|
|
(AliasSet::AccessLattice)AS.Access);
|
|
}
|
|
}
|
|
|
|
// deleteValue method - This method is used to remove a pointer value from the
|
|
// AliasSetTracker entirely. It should be used when an instruction is deleted
|
|
// from the program to update the AST. If you don't use this, you would have
|
|
// dangling pointers to deleted instructions.
|
|
//
|
|
void AliasSetTracker::deleteValue(Value *PtrVal) {
|
|
// First, look up the PointerRec for this pointer.
|
|
PointerMapType::iterator I = PointerMap.find_as(PtrVal);
|
|
if (I == PointerMap.end()) return; // Noop
|
|
|
|
// If we found one, remove the pointer from the alias set it is in.
|
|
AliasSet::PointerRec *PtrValEnt = I->second;
|
|
AliasSet *AS = PtrValEnt->getAliasSet(*this);
|
|
|
|
// Unlink and delete from the list of values.
|
|
PtrValEnt->eraseFromList();
|
|
|
|
if (AS->Alias == AliasSet::SetMayAlias) {
|
|
AS->SetSize--;
|
|
TotalMayAliasSetSize--;
|
|
}
|
|
|
|
// Stop using the alias set.
|
|
AS->dropRef(*this);
|
|
|
|
PointerMap.erase(I);
|
|
}
|
|
|
|
// copyValue - This method should be used whenever a preexisting value in the
|
|
// program is copied or cloned, introducing a new value. Note that it is ok for
|
|
// clients that use this method to introduce the same value multiple times: if
|
|
// the tracker already knows about a value, it will ignore the request.
|
|
//
|
|
void AliasSetTracker::copyValue(Value *From, Value *To) {
|
|
// First, look up the PointerRec for this pointer.
|
|
PointerMapType::iterator I = PointerMap.find_as(From);
|
|
if (I == PointerMap.end())
|
|
return; // Noop
|
|
assert(I->second->hasAliasSet() && "Dead entry?");
|
|
|
|
AliasSet::PointerRec &Entry = getEntryFor(To);
|
|
if (Entry.hasAliasSet()) return; // Already in the tracker!
|
|
|
|
// getEntryFor above may invalidate iterator \c I, so reinitialize it.
|
|
I = PointerMap.find_as(From);
|
|
// Add it to the alias set it aliases...
|
|
AliasSet *AS = I->second->getAliasSet(*this);
|
|
AS->addPointer(*this, Entry, I->second->getSize(), I->second->getAAInfo(),
|
|
true, true);
|
|
}
|
|
|
|
AliasSet &AliasSetTracker::mergeAllAliasSets() {
|
|
assert(!AliasAnyAS && (TotalMayAliasSetSize > SaturationThreshold) &&
|
|
"Full merge should happen once, when the saturation threshold is "
|
|
"reached");
|
|
|
|
// Collect all alias sets, so that we can drop references with impunity
|
|
// without worrying about iterator invalidation.
|
|
std::vector<AliasSet *> ASVector;
|
|
ASVector.reserve(SaturationThreshold);
|
|
for (AliasSet &AS : *this)
|
|
ASVector.push_back(&AS);
|
|
|
|
// Copy all instructions and pointers into a new set, and forward all other
|
|
// sets to it.
|
|
AliasSets.push_back(new AliasSet());
|
|
AliasAnyAS = &AliasSets.back();
|
|
AliasAnyAS->Alias = AliasSet::SetMayAlias;
|
|
AliasAnyAS->Access = AliasSet::ModRefAccess;
|
|
AliasAnyAS->AliasAny = true;
|
|
|
|
for (auto Cur : ASVector) {
|
|
// If Cur was already forwarding, just forward to the new AS instead.
|
|
AliasSet *FwdTo = Cur->Forward;
|
|
if (FwdTo) {
|
|
Cur->Forward = AliasAnyAS;
|
|
AliasAnyAS->addRef();
|
|
FwdTo->dropRef(*this);
|
|
continue;
|
|
}
|
|
|
|
// Otherwise, perform the actual merge.
|
|
AliasAnyAS->mergeSetIn(*Cur, *this);
|
|
}
|
|
|
|
return *AliasAnyAS;
|
|
}
|
|
|
|
AliasSet &AliasSetTracker::addPointer(MemoryLocation Loc,
|
|
AliasSet::AccessLattice E) {
|
|
AliasSet &AS = getAliasSetFor(Loc);
|
|
AS.Access |= E;
|
|
|
|
if (!AliasAnyAS && (TotalMayAliasSetSize > SaturationThreshold)) {
|
|
// The AST is now saturated. From here on, we conservatively consider all
|
|
// pointers to alias each-other.
|
|
return mergeAllAliasSets();
|
|
}
|
|
|
|
return AS;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// AliasSet/AliasSetTracker Printing Support
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void AliasSet::print(raw_ostream &OS) const {
|
|
OS << " AliasSet[" << (const void*)this << ", " << RefCount << "] ";
|
|
OS << (Alias == SetMustAlias ? "must" : "may") << " alias, ";
|
|
switch (Access) {
|
|
case NoAccess: OS << "No access "; break;
|
|
case RefAccess: OS << "Ref "; break;
|
|
case ModAccess: OS << "Mod "; break;
|
|
case ModRefAccess: OS << "Mod/Ref "; break;
|
|
default: llvm_unreachable("Bad value for Access!");
|
|
}
|
|
if (Forward)
|
|
OS << " forwarding to " << (void*)Forward;
|
|
|
|
if (!empty()) {
|
|
OS << "Pointers: ";
|
|
for (iterator I = begin(), E = end(); I != E; ++I) {
|
|
if (I != begin()) OS << ", ";
|
|
I.getPointer()->printAsOperand(OS << "(");
|
|
if (I.getSize() == LocationSize::afterPointer())
|
|
OS << ", unknown after)";
|
|
else if (I.getSize() == LocationSize::beforeOrAfterPointer())
|
|
OS << ", unknown before-or-after)";
|
|
else
|
|
OS << ", " << I.getSize() << ")";
|
|
}
|
|
}
|
|
if (!UnknownInsts.empty()) {
|
|
OS << "\n " << UnknownInsts.size() << " Unknown instructions: ";
|
|
for (unsigned i = 0, e = UnknownInsts.size(); i != e; ++i) {
|
|
if (i) OS << ", ";
|
|
if (auto *I = getUnknownInst(i)) {
|
|
if (I->hasName())
|
|
I->printAsOperand(OS);
|
|
else
|
|
I->print(OS);
|
|
}
|
|
}
|
|
}
|
|
OS << "\n";
|
|
}
|
|
|
|
void AliasSetTracker::print(raw_ostream &OS) const {
|
|
OS << "Alias Set Tracker: " << AliasSets.size();
|
|
if (AliasAnyAS)
|
|
OS << " (Saturated)";
|
|
OS << " alias sets for " << PointerMap.size() << " pointer values.\n";
|
|
for (const AliasSet &AS : *this)
|
|
AS.print(OS);
|
|
OS << "\n";
|
|
}
|
|
|
|
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
|
|
LLVM_DUMP_METHOD void AliasSet::dump() const { print(dbgs()); }
|
|
LLVM_DUMP_METHOD void AliasSetTracker::dump() const { print(dbgs()); }
|
|
#endif
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// ASTCallbackVH Class Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void AliasSetTracker::ASTCallbackVH::deleted() {
|
|
assert(AST && "ASTCallbackVH called with a null AliasSetTracker!");
|
|
AST->deleteValue(getValPtr());
|
|
// this now dangles!
|
|
}
|
|
|
|
void AliasSetTracker::ASTCallbackVH::allUsesReplacedWith(Value *V) {
|
|
AST->copyValue(getValPtr(), V);
|
|
}
|
|
|
|
AliasSetTracker::ASTCallbackVH::ASTCallbackVH(Value *V, AliasSetTracker *ast)
|
|
: CallbackVH(V), AST(ast) {}
|
|
|
|
AliasSetTracker::ASTCallbackVH &
|
|
AliasSetTracker::ASTCallbackVH::operator=(Value *V) {
|
|
return *this = ASTCallbackVH(V, AST);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// AliasSetPrinter Pass
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
|
|
class AliasSetPrinter : public FunctionPass {
|
|
public:
|
|
static char ID; // Pass identification, replacement for typeid
|
|
|
|
AliasSetPrinter() : FunctionPass(ID) {
|
|
initializeAliasSetPrinterPass(*PassRegistry::getPassRegistry());
|
|
}
|
|
|
|
void getAnalysisUsage(AnalysisUsage &AU) const override {
|
|
AU.setPreservesAll();
|
|
AU.addRequired<AAResultsWrapperPass>();
|
|
}
|
|
|
|
bool runOnFunction(Function &F) override {
|
|
auto &AAWP = getAnalysis<AAResultsWrapperPass>();
|
|
AliasSetTracker Tracker(AAWP.getAAResults());
|
|
errs() << "Alias sets for function '" << F.getName() << "':\n";
|
|
for (Instruction &I : instructions(F))
|
|
Tracker.add(&I);
|
|
Tracker.print(errs());
|
|
return false;
|
|
}
|
|
};
|
|
|
|
} // end anonymous namespace
|
|
|
|
char AliasSetPrinter::ID = 0;
|
|
|
|
INITIALIZE_PASS_BEGIN(AliasSetPrinter, "print-alias-sets",
|
|
"Alias Set Printer", false, true)
|
|
INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
|
|
INITIALIZE_PASS_END(AliasSetPrinter, "print-alias-sets",
|
|
"Alias Set Printer", false, true)
|
|
|
|
AliasSetsPrinterPass::AliasSetsPrinterPass(raw_ostream &OS) : OS(OS) {}
|
|
|
|
PreservedAnalyses AliasSetsPrinterPass::run(Function &F,
|
|
FunctionAnalysisManager &AM) {
|
|
auto &AA = AM.getResult<AAManager>(F);
|
|
AliasSetTracker Tracker(AA);
|
|
OS << "Alias sets for function '" << F.getName() << "':\n";
|
|
for (Instruction &I : instructions(F))
|
|
Tracker.add(&I);
|
|
Tracker.print(OS);
|
|
return PreservedAnalyses::all();
|
|
}
|