maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/polly/lib/Transform/Simplify.cpp

726 lines
27 KiB
C++
Raw Blame History

//===------ Simplify.cpp ----------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Simplify a SCoP by removing unnecessary statements and accesses.
//
//===----------------------------------------------------------------------===//
#include "polly/Simplify.h"
#include "polly/ScopInfo.h"
#include "polly/ScopPass.h"
#include "polly/Support/GICHelper.h"
#include "polly/Support/ISLOStream.h"
#include "polly/Support/ISLTools.h"
#include "polly/Support/VirtualInstruction.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/Debug.h"
#define DEBUG_TYPE "polly-simplify"
using namespace llvm;
using namespace polly;
namespace {
#define TWO_STATISTICS(VARNAME, DESC) \
static llvm::Statistic VARNAME[2] = { \
{DEBUG_TYPE, #VARNAME "0", DESC " (first)"}, \
{DEBUG_TYPE, #VARNAME "1", DESC " (second)"}}
/// Number of max disjuncts we allow in removeOverwrites(). This is to avoid
/// that the analysis of accesses in a statement is becoming too complex. Chosen
/// to be relatively small because all the common cases should access only few
/// array elements per statement.
static int const SimplifyMaxDisjuncts = 4;
TWO_STATISTICS(ScopsProcessed, "Number of SCoPs processed");
TWO_STATISTICS(ScopsModified, "Number of SCoPs simplified");
TWO_STATISTICS(TotalOverwritesRemoved, "Number of removed overwritten writes");
TWO_STATISTICS(TotalWritesCoalesced, "Number of writes coalesced with another");
TWO_STATISTICS(TotalRedundantWritesRemoved,
"Number of writes of same value removed in any SCoP");
TWO_STATISTICS(TotalEmptyPartialAccessesRemoved,
"Number of empty partial accesses removed");
TWO_STATISTICS(TotalDeadAccessesRemoved, "Number of dead accesses removed");
TWO_STATISTICS(TotalDeadInstructionsRemoved,
"Number of unused instructions removed");
TWO_STATISTICS(TotalStmtsRemoved, "Number of statements removed in any SCoP");
TWO_STATISTICS(NumValueWrites, "Number of scalar value writes after Simplify");
TWO_STATISTICS(
NumValueWritesInLoops,
"Number of scalar value writes nested in affine loops after Simplify");
TWO_STATISTICS(NumPHIWrites,
"Number of scalar phi writes after the first simplification");
TWO_STATISTICS(
NumPHIWritesInLoops,
"Number of scalar phi writes nested in affine loops after Simplify");
TWO_STATISTICS(NumSingletonWrites, "Number of singleton writes after Simplify");
TWO_STATISTICS(
NumSingletonWritesInLoops,
"Number of singleton writes nested in affine loops after Simplify");
static bool isImplicitRead(MemoryAccess *MA) {
return MA->isRead() && MA->isOriginalScalarKind();
}
static bool isExplicitAccess(MemoryAccess *MA) {
return MA->isOriginalArrayKind();
}
static bool isImplicitWrite(MemoryAccess *MA) {
return MA->isWrite() && MA->isOriginalScalarKind();
}
/// Like isl::union_map::add_map, but may also return an underapproximated
/// result if getting too complex.
///
/// This is implemented by adding disjuncts to the results until the limit is
/// reached.
static isl::union_map underapproximatedAddMap(isl::union_map UMap,
isl::map Map) {
if (UMap.is_null() || Map.is_null())
return {};
isl::map PrevMap = UMap.extract_map(Map.get_space());
// Fast path: If known that we cannot exceed the disjunct limit, just add
// them.
if (isl_map_n_basic_map(PrevMap.get()) + isl_map_n_basic_map(Map.get()) <=
SimplifyMaxDisjuncts)
return UMap.add_map(Map);
isl::map Result = isl::map::empty(PrevMap.get_space());
for (isl::basic_map BMap : PrevMap.get_basic_map_list()) {
if (Result.n_basic_map() > SimplifyMaxDisjuncts)
break;
Result = Result.unite(BMap);
}
for (isl::basic_map BMap : Map.get_basic_map_list()) {
if (isl_map_n_basic_map(Result.get()) > SimplifyMaxDisjuncts)
break;
Result = Result.unite(BMap);
}
isl::union_map UResult =
UMap.subtract(isl::map::universe(PrevMap.get_space()));
UResult.add_map(Result);
return UResult;
}
class Simplify : public ScopPass {
private:
/// The invocation id (if there are multiple instances in the pass manager's
/// pipeline) to determine which statistics to update.
int CallNo;
/// The last/current SCoP that is/has been processed.
Scop *S;
/// Number of writes that are overwritten anyway.
int OverwritesRemoved = 0;
/// Number of combined writes.
int WritesCoalesced = 0;
/// Number of redundant writes removed from this SCoP.
int RedundantWritesRemoved = 0;
/// Number of writes with empty access domain removed.
int EmptyPartialAccessesRemoved = 0;
/// Number of unused accesses removed from this SCoP.
int DeadAccessesRemoved = 0;
/// Number of unused instructions removed from this SCoP.
int DeadInstructionsRemoved = 0;
/// Number of unnecessary statements removed from the SCoP.
int StmtsRemoved = 0;
/// Return whether at least one simplification has been applied.
bool isModified() const {
return OverwritesRemoved > 0 || WritesCoalesced > 0 ||
RedundantWritesRemoved > 0 || EmptyPartialAccessesRemoved > 0 ||
DeadAccessesRemoved > 0 || DeadInstructionsRemoved > 0 ||
StmtsRemoved > 0;
}
/// Remove writes that are overwritten unconditionally later in the same
/// statement.
///
/// There must be no read of the same value between the write (that is to be
/// removed) and the overwrite.
void removeOverwrites() {
for (auto &Stmt : *S) {
isl::set Domain = Stmt.getDomain();
isl::union_map WillBeOverwritten =
isl::union_map::empty(S->getParamSpace());
SmallVector<MemoryAccess *, 32> Accesses(getAccessesInOrder(Stmt));
// Iterate in reverse order, so the overwrite comes before the write that
// is to be removed.
for (auto *MA : reverse(Accesses)) {
// In region statements, the explicit accesses can be in blocks that are
// can be executed in any order. We therefore process only the implicit
// writes and stop after that.
if (Stmt.isRegionStmt() && isExplicitAccess(MA))
break;
auto AccRel = MA->getAccessRelation();
AccRel = AccRel.intersect_domain(Domain);
AccRel = AccRel.intersect_params(S->getContext());
// If a value is read in-between, do not consider it as overwritten.
if (MA->isRead()) {
// Invalidate all overwrites for the array it accesses to avoid too
// complex isl sets.
isl::map AccRelUniv = isl::map::universe(AccRel.get_space());
WillBeOverwritten = WillBeOverwritten.subtract(AccRelUniv);
continue;
}
// If all of a write's elements are overwritten, remove it.
isl::union_map AccRelUnion = AccRel;
if (AccRelUnion.is_subset(WillBeOverwritten)) {
LLVM_DEBUG(dbgs() << "Removing " << MA
<< " which will be overwritten anyway\n");
Stmt.removeSingleMemoryAccess(MA);
OverwritesRemoved++;
TotalOverwritesRemoved[CallNo]++;
}
// Unconditional writes overwrite other values.
if (MA->isMustWrite()) {
// Avoid too complex isl sets. If necessary, throw away some of the
// knowledge.
WillBeOverwritten =
underapproximatedAddMap(WillBeOverwritten, AccRel);
}
}
}
}
/// Combine writes that write the same value if possible.
///
/// This function is able to combine:
/// - Partial writes with disjoint domain.
/// - Writes that write to the same array element.
///
/// In all cases, both writes must write the same values.
void coalesceWrites() {
for (auto &Stmt : *S) {
isl::set Domain = Stmt.getDomain().intersect_params(S->getContext());
// We let isl do the lookup for the same-value condition. For this, we
// wrap llvm::Value into an isl::set such that isl can do the lookup in
// its hashtable implementation. llvm::Values are only compared within a
// ScopStmt, so the map can be local to this scope. TODO: Refactor with
// ZoneAlgorithm::makeValueSet()
SmallDenseMap<Value *, isl::set> ValueSets;
auto makeValueSet = [&ValueSets, this](Value *V) -> isl::set {
assert(V);
isl::set &Result = ValueSets[V];
if (Result.is_null()) {
isl::ctx Ctx = S->getIslCtx();
std::string Name =
getIslCompatibleName("Val", V, ValueSets.size() - 1,
std::string(), UseInstructionNames);
isl::id Id = isl::id::alloc(Ctx, Name, V);
Result = isl::set::universe(
isl::space(Ctx, 0, 0).set_tuple_id(isl::dim::set, Id));
}
return Result;
};
// List of all eligible (for coalescing) writes of the future.
// { [Domain[] -> Element[]] -> [Value[] -> MemoryAccess[]] }
isl::union_map FutureWrites = isl::union_map::empty(S->getParamSpace());
// Iterate over accesses from the last to the first.
SmallVector<MemoryAccess *, 32> Accesses(getAccessesInOrder(Stmt));
for (MemoryAccess *MA : reverse(Accesses)) {
// In region statements, the explicit accesses can be in blocks that can
// be executed in any order. We therefore process only the implicit
// writes and stop after that.
if (Stmt.isRegionStmt() && isExplicitAccess(MA))
break;
// { Domain[] -> Element[] }
isl::map AccRel =
MA->getLatestAccessRelation().intersect_domain(Domain);
// { [Domain[] -> Element[]] }
isl::set AccRelWrapped = AccRel.wrap();
// { Value[] }
isl::set ValSet;
if (MA->isMustWrite() && (MA->isOriginalScalarKind() ||
isa<StoreInst>(MA->getAccessInstruction()))) {
// Normally, tryGetValueStored() should be used to determine which
// element is written, but it can return nullptr; For PHI accesses,
// getAccessValue() returns the PHI instead of the PHI's incoming
// value. In this case, where we only compare values of a single
// statement, this is fine, because within a statement, a PHI in a
// successor block has always the same value as the incoming write. We
// still preferably use the incoming value directly so we also catch
// direct uses of that.
Value *StoredVal = MA->tryGetValueStored();
if (!StoredVal)
StoredVal = MA->getAccessValue();
ValSet = makeValueSet(StoredVal);
// { Domain[] }
isl::set AccDomain = AccRel.domain();
// Parts of the statement's domain that is not written by this access.
isl::set UndefDomain = Domain.subtract(AccDomain);
// { Element[] }
isl::set ElementUniverse =
isl::set::universe(AccRel.get_space().range());
// { Domain[] -> Element[] }
isl::map UndefAnything =
isl::map::from_domain_and_range(UndefDomain, ElementUniverse);
// We are looking a compatible write access. The other write can
// access these elements...
isl::map AllowedAccesses = AccRel.unite(UndefAnything);
// ... and must write the same value.
// { [Domain[] -> Element[]] -> Value[] }
isl::map Filter =
isl::map::from_domain_and_range(AllowedAccesses.wrap(), ValSet);
// Lookup future write that fulfills these conditions.
// { [[Domain[] -> Element[]] -> Value[]] -> MemoryAccess[] }
isl::union_map Filtered =
FutureWrites.uncurry().intersect_domain(Filter.wrap());
// Iterate through the candidates.
for (isl::map Map : Filtered.get_map_list()) {
MemoryAccess *OtherMA = (MemoryAccess *)Map.get_space()
.get_tuple_id(isl::dim::out)
.get_user();
isl::map OtherAccRel =
OtherMA->getLatestAccessRelation().intersect_domain(Domain);
// The filter only guaranteed that some of OtherMA's accessed
// elements are allowed. Verify that it only accesses allowed
// elements. Otherwise, continue with the next candidate.
if (!OtherAccRel.is_subset(AllowedAccesses).is_true())
continue;
// The combined access relation.
// { Domain[] -> Element[] }
isl::map NewAccRel = AccRel.unite(OtherAccRel);
simplify(NewAccRel);
// Carry out the coalescing.
Stmt.removeSingleMemoryAccess(MA);
OtherMA->setNewAccessRelation(NewAccRel);
// We removed MA, OtherMA takes its role.
MA = OtherMA;
TotalWritesCoalesced[CallNo]++;
WritesCoalesced++;
// Don't look for more candidates.
break;
}
}
// Two writes cannot be coalesced if there is another access (to some of
// the written elements) between them. Remove all visited write accesses
// from the list of eligible writes. Don't just remove the accessed
// elements, but any MemoryAccess that touches any of the invalidated
// elements.
SmallPtrSet<MemoryAccess *, 2> TouchedAccesses;
for (isl::map Map :
FutureWrites.intersect_domain(AccRelWrapped).get_map_list()) {
MemoryAccess *MA = (MemoryAccess *)Map.get_space()
.range()
.unwrap()
.get_tuple_id(isl::dim::out)
.get_user();
TouchedAccesses.insert(MA);
}
isl::union_map NewFutureWrites =
isl::union_map::empty(FutureWrites.get_space());
for (isl::map FutureWrite : FutureWrites.get_map_list()) {
MemoryAccess *MA = (MemoryAccess *)FutureWrite.get_space()
.range()
.unwrap()
.get_tuple_id(isl::dim::out)
.get_user();
if (!TouchedAccesses.count(MA))
NewFutureWrites = NewFutureWrites.add_map(FutureWrite);
}
FutureWrites = NewFutureWrites;
if (MA->isMustWrite() && !ValSet.is_null()) {
// { MemoryAccess[] }
auto AccSet =
isl::set::universe(isl::space(S->getIslCtx(), 0, 0)
.set_tuple_id(isl::dim::set, MA->getId()));
// { Val[] -> MemoryAccess[] }
isl::map ValAccSet = isl::map::from_domain_and_range(ValSet, AccSet);
// { [Domain[] -> Element[]] -> [Value[] -> MemoryAccess[]] }
isl::map AccRelValAcc =
isl::map::from_domain_and_range(AccRelWrapped, ValAccSet.wrap());
FutureWrites = FutureWrites.add_map(AccRelValAcc);
}
}
}
}
/// Remove writes that just write the same value already stored in the
/// element.
void removeRedundantWrites() {
for (auto &Stmt : *S) {
SmallDenseMap<Value *, isl::set> ValueSets;
auto makeValueSet = [&ValueSets, this](Value *V) -> isl::set {
assert(V);
isl::set &Result = ValueSets[V];
if (Result.is_null()) {
isl_ctx *Ctx = S->getIslCtx().get();
std::string Name =
getIslCompatibleName("Val", V, ValueSets.size() - 1,
std::string(), UseInstructionNames);
isl::id Id = isl::manage(isl_id_alloc(Ctx, Name.c_str(), V));
Result = isl::set::universe(
isl::space(Ctx, 0, 0).set_tuple_id(isl::dim::set, Id));
}
return Result;
};
isl::set Domain = Stmt.getDomain();
Domain = Domain.intersect_params(S->getContext());
// List of element reads that still have the same value while iterating
// through the MemoryAccesses.
// { [Domain[] -> Element[]] -> Val[] }
isl::union_map Known = isl::union_map::empty(S->getParamSpace());
SmallVector<MemoryAccess *, 32> Accesses(getAccessesInOrder(Stmt));
for (MemoryAccess *MA : Accesses) {
// Is the memory access in a defined order relative to the other
// accesses? In region statements, only the first and the last accesses
// have defined order. Execution of those in the middle may depend on
// runtime conditions an therefore cannot be modified.
bool IsOrdered =
Stmt.isBlockStmt() || MA->isOriginalScalarKind() ||
(!S->getBoxedLoops().size() && MA->getAccessInstruction() &&
Stmt.getEntryBlock() == MA->getAccessInstruction()->getParent());
isl::map AccRel = MA->getAccessRelation();
AccRel = AccRel.intersect_domain(Domain);
isl::set AccRelWrapped = AccRel.wrap();
// Determine whether a write is redundant (stores only values that are
// already present in the written array elements) and remove it if this
// is the case.
if (IsOrdered && MA->isMustWrite() &&
(isa<StoreInst>(MA->getAccessInstruction()) ||
MA->isOriginalScalarKind())) {
Value *StoredVal = MA->tryGetValueStored();
if (!StoredVal)
StoredVal = MA->getAccessValue();
if (StoredVal) {
// Lookup in the set of known values.
isl::map AccRelStoredVal = isl::map::from_domain_and_range(
AccRelWrapped, makeValueSet(StoredVal));
if (isl::union_map(AccRelStoredVal).is_subset(Known)) {
LLVM_DEBUG(dbgs() << "Cleanup of " << MA << ":\n");
LLVM_DEBUG(dbgs() << " Scalar: " << *StoredVal << "\n");
LLVM_DEBUG(dbgs() << " AccRel: " << AccRel << "\n");
Stmt.removeSingleMemoryAccess(MA);
RedundantWritesRemoved++;
TotalRedundantWritesRemoved[CallNo]++;
}
}
}
// Update the know values set.
if (MA->isRead()) {
// Loaded values are the currently known values of the array element
// it was loaded from.
Value *LoadedVal = MA->getAccessValue();
if (LoadedVal && IsOrdered) {
isl::map AccRelVal = isl::map::from_domain_and_range(
AccRelWrapped, makeValueSet(LoadedVal));
Known = Known.add_map(AccRelVal);
}
} else if (MA->isWrite()) {
// Remove (possibly) overwritten values from the known elements set.
// We remove all elements of the accessed array to avoid too complex
// isl sets.
isl::set AccRelUniv = isl::set::universe(AccRelWrapped.get_space());
Known = Known.subtract_domain(AccRelUniv);
// At this point, we could add the written value of must-writes.
// However, writing same values is already handled by
// coalesceWrites().
}
}
}
}
/// Remove statements without side effects.
void removeUnnecessaryStmts() {
auto NumStmtsBefore = S->getSize();
S->simplifySCoP(true);
assert(NumStmtsBefore >= S->getSize());
StmtsRemoved = NumStmtsBefore - S->getSize();
LLVM_DEBUG(dbgs() << "Removed " << StmtsRemoved << " (of " << NumStmtsBefore
<< ") statements\n");
TotalStmtsRemoved[CallNo] += StmtsRemoved;
}
/// Remove accesses that have an empty domain.
void removeEmptyPartialAccesses() {
for (ScopStmt &Stmt : *S) {
// Defer the actual removal to not invalidate iterators.
SmallVector<MemoryAccess *, 8> DeferredRemove;
for (MemoryAccess *MA : Stmt) {
if (!MA->isWrite())
continue;
isl::map AccRel = MA->getAccessRelation();
if (!AccRel.is_empty().is_true())
continue;
LLVM_DEBUG(
dbgs() << "Removing " << MA
<< " because it's a partial access that never occurs\n");
DeferredRemove.push_back(MA);
}
for (MemoryAccess *MA : DeferredRemove) {
Stmt.removeSingleMemoryAccess(MA);
EmptyPartialAccessesRemoved++;
TotalEmptyPartialAccessesRemoved[CallNo]++;
}
}
}
/// Mark all reachable instructions and access, and sweep those that are not
/// reachable.
void markAndSweep(LoopInfo *LI) {
DenseSet<MemoryAccess *> UsedMA;
DenseSet<VirtualInstruction> UsedInsts;
// Get all reachable instructions and accesses.
markReachable(S, LI, UsedInsts, UsedMA);
// Remove all non-reachable accesses.
// We need get all MemoryAccesses first, in order to not invalidate the
// iterators when removing them.
SmallVector<MemoryAccess *, 64> AllMAs;
for (ScopStmt &Stmt : *S)
AllMAs.append(Stmt.begin(), Stmt.end());
for (MemoryAccess *MA : AllMAs) {
if (UsedMA.count(MA))
continue;
LLVM_DEBUG(dbgs() << "Removing " << MA
<< " because its value is not used\n");
ScopStmt *Stmt = MA->getStatement();
Stmt->removeSingleMemoryAccess(MA);
DeadAccessesRemoved++;
TotalDeadAccessesRemoved[CallNo]++;
}
// Remove all non-reachable instructions.
for (ScopStmt &Stmt : *S) {
// Note that for region statements, we can only remove the non-terminator
// instructions of the entry block. All other instructions are not in the
// instructions list, but implicitly always part of the statement.
SmallVector<Instruction *, 32> AllInsts(Stmt.insts_begin(),
Stmt.insts_end());
SmallVector<Instruction *, 32> RemainInsts;
for (Instruction *Inst : AllInsts) {
auto It = UsedInsts.find({&Stmt, Inst});
if (It == UsedInsts.end()) {
LLVM_DEBUG(dbgs() << "Removing "; Inst->print(dbgs());
dbgs() << " because it is not used\n");
DeadInstructionsRemoved++;
TotalDeadInstructionsRemoved[CallNo]++;
continue;
}
RemainInsts.push_back(Inst);
// If instructions appear multiple times, keep only the first.
UsedInsts.erase(It);
}
// Set the new instruction list to be only those we did not remove.
Stmt.setInstructions(RemainInsts);
}
}
/// Print simplification statistics to @p OS.
void printStatistics(llvm::raw_ostream &OS, int Indent = 0) const {
OS.indent(Indent) << "Statistics {\n";
OS.indent(Indent + 4) << "Overwrites removed: " << OverwritesRemoved
<< '\n';
OS.indent(Indent + 4) << "Partial writes coalesced: " << WritesCoalesced
<< "\n";
OS.indent(Indent + 4) << "Redundant writes removed: "
<< RedundantWritesRemoved << "\n";
OS.indent(Indent + 4) << "Accesses with empty domains removed: "
<< EmptyPartialAccessesRemoved << "\n";
OS.indent(Indent + 4) << "Dead accesses removed: " << DeadAccessesRemoved
<< '\n';
OS.indent(Indent + 4) << "Dead instructions removed: "
<< DeadInstructionsRemoved << '\n';
OS.indent(Indent + 4) << "Stmts removed: " << StmtsRemoved << "\n";
OS.indent(Indent) << "}\n";
}
/// Print the current state of all MemoryAccesses to @p OS.
void printAccesses(llvm::raw_ostream &OS, int Indent = 0) const {
OS.indent(Indent) << "After accesses {\n";
for (auto &Stmt : *S) {
OS.indent(Indent + 4) << Stmt.getBaseName() << "\n";
for (auto *MA : Stmt)
MA->print(OS);
}
OS.indent(Indent) << "}\n";
}
public:
static char ID;
explicit Simplify(int CallNo = 0) : ScopPass(ID), CallNo(CallNo) {}
virtual void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequiredTransitive<ScopInfoRegionPass>();
AU.addRequired<LoopInfoWrapperPass>();
AU.setPreservesAll();
}
virtual bool runOnScop(Scop &S) override {
// Reset statistics of last processed SCoP.
releaseMemory();
assert(!isModified());
// Prepare processing of this SCoP.
this->S = &S;
ScopsProcessed[CallNo]++;
LLVM_DEBUG(dbgs() << "Removing partial writes that never happen...\n");
removeEmptyPartialAccesses();
LLVM_DEBUG(dbgs() << "Removing overwrites...\n");
removeOverwrites();
LLVM_DEBUG(dbgs() << "Coalesce partial writes...\n");
coalesceWrites();
LLVM_DEBUG(dbgs() << "Removing redundant writes...\n");
removeRedundantWrites();
LLVM_DEBUG(dbgs() << "Cleanup unused accesses...\n");
LoopInfo *LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
markAndSweep(LI);
LLVM_DEBUG(dbgs() << "Removing statements without side effects...\n");
removeUnnecessaryStmts();
if (isModified())
ScopsModified[CallNo]++;
LLVM_DEBUG(dbgs() << "\nFinal Scop:\n");
LLVM_DEBUG(dbgs() << S);
auto ScopStats = S.getStatistics();
NumValueWrites[CallNo] += ScopStats.NumValueWrites;
NumValueWritesInLoops[CallNo] += ScopStats.NumValueWritesInLoops;
NumPHIWrites[CallNo] += ScopStats.NumPHIWrites;
NumPHIWritesInLoops[CallNo] += ScopStats.NumPHIWritesInLoops;
NumSingletonWrites[CallNo] += ScopStats.NumSingletonWrites;
NumSingletonWritesInLoops[CallNo] += ScopStats.NumSingletonWritesInLoops;
return false;
}
virtual void printScop(raw_ostream &OS, Scop &S) const override {
assert(&S == this->S &&
"Can only print analysis for the last processed SCoP");
printStatistics(OS);
if (!isModified()) {
OS << "SCoP could not be simplified\n";
return;
}
printAccesses(OS);
}
virtual void releaseMemory() override {
S = nullptr;
OverwritesRemoved = 0;
WritesCoalesced = 0;
RedundantWritesRemoved = 0;
EmptyPartialAccessesRemoved = 0;
DeadAccessesRemoved = 0;
DeadInstructionsRemoved = 0;
StmtsRemoved = 0;
}
};
char Simplify::ID;
} // anonymous namespace
namespace polly {
SmallVector<MemoryAccess *, 32> getAccessesInOrder(ScopStmt &Stmt) {
SmallVector<MemoryAccess *, 32> Accesses;
for (MemoryAccess *MemAcc : Stmt)
if (isImplicitRead(MemAcc))
Accesses.push_back(MemAcc);
for (MemoryAccess *MemAcc : Stmt)
if (isExplicitAccess(MemAcc))
Accesses.push_back(MemAcc);
for (MemoryAccess *MemAcc : Stmt)
if (isImplicitWrite(MemAcc))
Accesses.push_back(MemAcc);
return Accesses;
}
} // namespace polly
Pass *polly::createSimplifyPass(int CallNo) { return new Simplify(CallNo); }
INITIALIZE_PASS_BEGIN(Simplify, "polly-simplify", "Polly - Simplify", false,
false)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_END(Simplify, "polly-simplify", "Polly - Simplify", false,
false)
Reference in New Issue View Git Blame Copy Permalink