#define DEBUG_TYPE "isel-opt"
#include "DAGISelMatcher.h"
-#include "llvm/ADT/DenseMap.h"
+#include "CodeGenDAGPatterns.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/StringSet.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
-#include <vector>
using namespace llvm;
/// ContractNodes - Turn multiple matcher node patterns like 'MoveChild+Record'
/// into single compound nodes like RecordChild.
-static void ContractNodes(OwningPtr<Matcher> &MatcherPtr) {
+static void ContractNodes(OwningPtr<Matcher> &MatcherPtr,
+ const CodeGenDAGPatterns &CGP) {
// If we reached the end of the chain, we're done.
Matcher *N = MatcherPtr.get();
if (N == 0) return;
if (ScopeMatcher *Scope = dyn_cast<ScopeMatcher>(N)) {
for (unsigned i = 0, e = Scope->getNumChildren(); i != e; ++i) {
OwningPtr<Matcher> Child(Scope->takeChild(i));
- ContractNodes(Child);
+ ContractNodes(Child, CGP);
Scope->resetChild(i, Child.take());
}
return;
if (MoveChildMatcher *MC = dyn_cast<MoveChildMatcher>(N)) {
Matcher *New = 0;
if (RecordMatcher *RM = dyn_cast<RecordMatcher>(MC->getNext()))
- New = new RecordChildMatcher(MC->getChildNo(), RM->getWhatFor());
+ if (MC->getChildNo() < 8) // Only have RecordChild0...7
+ New = new RecordChildMatcher(MC->getChildNo(), RM->getWhatFor(),
+ RM->getResultNo());
- if (CheckTypeMatcher *CT= dyn_cast<CheckTypeMatcher>(MC->getNext()))
- New = new CheckChildTypeMatcher(MC->getChildNo(), CT->getType());
+ if (CheckTypeMatcher *CT = dyn_cast<CheckTypeMatcher>(MC->getNext()))
+ if (MC->getChildNo() < 8 && // Only have CheckChildType0...7
+ CT->getResNo() == 0) // CheckChildType checks res #0
+ New = new CheckChildTypeMatcher(MC->getChildNo(), CT->getType());
if (New) {
// Insert the new node.
MatcherPtr.reset(New);
// Remove the old one.
MC->setNext(MC->getNext()->takeNext());
- return ContractNodes(MatcherPtr);
+ return ContractNodes(MatcherPtr, CGP);
}
}
if (MoveParentMatcher *MP =
dyn_cast<MoveParentMatcher>(MC->getNext())) {
MatcherPtr.reset(MP->takeNext());
- return ContractNodes(MatcherPtr);
+ return ContractNodes(MatcherPtr, CGP);
}
-
- // Turn EmitNode->CompleteMatch into SelectNodeTo if we can.
+
+ // Turn EmitNode->MarkFlagResults->CompleteMatch into
+ // MarkFlagResults->EmitNode->CompleteMatch when we can to encourage
+ // MorphNodeTo formation. This is safe because MarkFlagResults never refers
+ // to the root of the pattern.
+ if (isa<EmitNodeMatcher>(N) && isa<MarkGlueResultsMatcher>(N->getNext()) &&
+ isa<CompleteMatchMatcher>(N->getNext()->getNext())) {
+ // Unlink the two nodes from the list.
+ Matcher *EmitNode = MatcherPtr.take();
+ Matcher *MFR = EmitNode->takeNext();
+ Matcher *Tail = MFR->takeNext();
+
+ // Relink them.
+ MatcherPtr.reset(MFR);
+ MFR->setNext(EmitNode);
+ EmitNode->setNext(Tail);
+ return ContractNodes(MatcherPtr, CGP);
+ }
+
+ // Turn EmitNode->CompleteMatch into MorphNodeTo if we can.
if (EmitNodeMatcher *EN = dyn_cast<EmitNodeMatcher>(N))
if (CompleteMatchMatcher *CM =
dyn_cast<CompleteMatchMatcher>(EN->getNext())) {
- (void)CM;
+ // We can only use MorphNodeTo if the result values match up.
+ unsigned RootResultFirst = EN->getFirstResultSlot();
+ bool ResultsMatch = true;
+ for (unsigned i = 0, e = CM->getNumResults(); i != e; ++i)
+ if (CM->getResult(i) != RootResultFirst+i)
+ ResultsMatch = false;
+
+ // If the selected node defines a subset of the glue/chain results, we
+ // can't use MorphNodeTo. For example, we can't use MorphNodeTo if the
+ // matched pattern has a chain but the root node doesn't.
+ const PatternToMatch &Pattern = CM->getPattern();
+
+ if (!EN->hasChain() &&
+ Pattern.getSrcPattern()->NodeHasProperty(SDNPHasChain, CGP))
+ ResultsMatch = false;
+
+ // If the matched node has glue and the output root doesn't, we can't
+ // use MorphNodeTo.
+ //
+ // NOTE: Strictly speaking, we don't have to check for glue here
+ // because the code in the pattern generator doesn't handle it right. We
+ // do it anyway for thoroughness.
+ if (!EN->hasOutFlag() &&
+ Pattern.getSrcPattern()->NodeHasProperty(SDNPOutGlue, CGP))
+ ResultsMatch = false;
+
+
+ // If the root result node defines more results than the source root node
+ // *and* has a chain or glue input, then we can't match it because it
+ // would end up replacing the extra result with the chain/glue.
+#if 0
+ if ((EN->hasGlue() || EN->hasChain()) &&
+ EN->getNumNonChainGlueVTs() > ... need to get no results reliably ...)
+ ResultMatch = false;
+#endif
+
+ if (ResultsMatch) {
+ const SmallVectorImpl<MVT::SimpleValueType> &VTs = EN->getVTList();
+ const SmallVectorImpl<unsigned> &Operands = EN->getOperandList();
+ MatcherPtr.reset(new MorphNodeToMatcher(EN->getOpcodeName(),
+ VTs.data(), VTs.size(),
+ Operands.data(),Operands.size(),
+ EN->hasChain(), EN->hasInFlag(),
+ EN->hasOutFlag(),
+ EN->hasMemRefs(),
+ EN->getNumFixedArityOperands(),
+ Pattern));
+ return;
+ }
+
+ // FIXME2: Kill off all the SelectionDAG::SelectNodeTo and getMachineNode
+ // variants.
}
- ContractNodes(N->getNextPtr());
+ ContractNodes(N->getNextPtr(), CGP);
+
+
+ // If we have a CheckType/CheckChildType/Record node followed by a
+ // CheckOpcode, invert the two nodes. We prefer to do structural checks
+ // before type checks, as this opens opportunities for factoring on targets
+ // like X86 where many operations are valid on multiple types.
+ if ((isa<CheckTypeMatcher>(N) || isa<CheckChildTypeMatcher>(N) ||
+ isa<RecordMatcher>(N)) &&
+ isa<CheckOpcodeMatcher>(N->getNext())) {
+ // Unlink the two nodes from the list.
+ Matcher *CheckType = MatcherPtr.take();
+ Matcher *CheckOpcode = CheckType->takeNext();
+ Matcher *Tail = CheckOpcode->takeNext();
+
+ // Relink them.
+ MatcherPtr.reset(CheckOpcode);
+ CheckOpcode->setNext(CheckType);
+ CheckType->setNext(Tail);
+ return ContractNodes(MatcherPtr, CGP);
+ }
}
/// SinkPatternPredicates - Pattern predicates can be checked at any level of
N->setNext(CPPM);
}
+/// FindNodeWithKind - Scan a series of matchers looking for a matcher with a
+/// specified kind. Return null if we didn't find one otherwise return the
+/// matcher.
+static Matcher *FindNodeWithKind(Matcher *M, Matcher::KindTy Kind) {
+ for (; M; M = M->getNext())
+ if (M->getKind() == Kind)
+ return M;
+ return 0;
+}
+
+
/// FactorNodes - Turn matches like this:
/// Scope
/// OPC_CheckType i32
}
SmallVector<Matcher*, 32> NewOptionsToMatch;
-
+
// Loop over options to match, merging neighboring patterns with identical
// starting nodes into a shared matcher.
for (unsigned OptionIdx = 0, e = OptionsToMatch.size(); OptionIdx != e;) {
// we can merge anything else into this matching group.
unsigned Scan = OptionIdx;
while (1) {
- while (Scan != e && Optn->isContradictory(OptionsToMatch[Scan]))
- ++Scan;
+ // If we ran out of stuff to scan, we're done.
+ if (Scan == e) break;
- // Ok, we found something that isn't known to be contradictory. If it is
- // equal, we can merge it into the set of nodes to factor, if not, we have
- // to cease factoring.
- if (Scan == e || !Optn->isEqual(OptionsToMatch[Scan])) break;
+ Matcher *ScanMatcher = OptionsToMatch[Scan];
+
+ // If we found an entry that matches out matcher, merge it into the set to
+ // handle.
+ if (Optn->isEqual(ScanMatcher)) {
+ // If is equal after all, add the option to EqualMatchers and remove it
+ // from OptionsToMatch.
+ EqualMatchers.push_back(ScanMatcher);
+ OptionsToMatch.erase(OptionsToMatch.begin()+Scan);
+ --e;
+ continue;
+ }
+
+ // If the option we're checking for contradicts the start of the list,
+ // skip over it.
+ if (Optn->isContradictory(ScanMatcher)) {
+ ++Scan;
+ continue;
+ }
- // If is equal after all, add the option to EqualMatchers and remove it
- // from OptionsToMatch.
- EqualMatchers.push_back(OptionsToMatch[Scan]);
- OptionsToMatch.erase(OptionsToMatch.begin()+Scan);
- --e;
+ // If we're scanning for a simple node, see if it occurs later in the
+ // sequence. If so, and if we can move it up, it might be contradictory
+ // or the same as what we're looking for. If so, reorder it.
+ if (Optn->isSimplePredicateOrRecordNode()) {
+ Matcher *M2 = FindNodeWithKind(ScanMatcher, Optn->getKind());
+ if (M2 != 0 && M2 != ScanMatcher &&
+ M2->canMoveBefore(ScanMatcher) &&
+ (M2->isEqual(Optn) || M2->isContradictory(Optn))) {
+ Matcher *MatcherWithoutM2 = ScanMatcher->unlinkNode(M2);
+ M2->setNext(MatcherWithoutM2);
+ OptionsToMatch[Scan] = M2;
+ continue;
+ }
+ }
+
+ // Otherwise, we don't know how to handle this entry, we have to bail.
+ break;
}
if (Scan != e &&
NewOptionsToMatch.push_back(Shared);
}
-
- // Reassemble a new Scope node.
- assert(!NewOptionsToMatch.empty() && "where'd all our children go?");
- if (NewOptionsToMatch.size() == 1)
+
+ // If we're down to a single pattern to match, then we don't need this scope
+ // anymore.
+ if (NewOptionsToMatch.size() == 1) {
MatcherPtr.reset(NewOptionsToMatch[0]);
- else {
- Scope->setNumChildren(NewOptionsToMatch.size());
- for (unsigned i = 0, e = NewOptionsToMatch.size(); i != e; ++i)
- Scope->resetChild(i, NewOptionsToMatch[i]);
+ return;
+ }
+
+ if (NewOptionsToMatch.empty()) {
+ MatcherPtr.reset(0);
+ return;
}
+
+ // If our factoring failed (didn't achieve anything) see if we can simplify in
+ // other ways.
+
+ // Check to see if all of the leading entries are now opcode checks. If so,
+ // we can convert this Scope to be a OpcodeSwitch instead.
+ bool AllOpcodeChecks = true, AllTypeChecks = true;
+ for (unsigned i = 0, e = NewOptionsToMatch.size(); i != e; ++i) {
+ // Check to see if this breaks a series of CheckOpcodeMatchers.
+ if (AllOpcodeChecks &&
+ !isa<CheckOpcodeMatcher>(NewOptionsToMatch[i])) {
+#if 0
+ if (i > 3) {
+ errs() << "FAILING OPC #" << i << "\n";
+ NewOptionsToMatch[i]->dump();
+ }
+#endif
+ AllOpcodeChecks = false;
+ }
+
+ // Check to see if this breaks a series of CheckTypeMatcher's.
+ if (AllTypeChecks) {
+ CheckTypeMatcher *CTM =
+ cast_or_null<CheckTypeMatcher>(FindNodeWithKind(NewOptionsToMatch[i],
+ Matcher::CheckType));
+ if (CTM == 0 ||
+ // iPTR checks could alias any other case without us knowing, don't
+ // bother with them.
+ CTM->getType() == MVT::iPTR ||
+ // SwitchType only works for result #0.
+ CTM->getResNo() != 0 ||
+ // If the CheckType isn't at the start of the list, see if we can move
+ // it there.
+ !CTM->canMoveBefore(NewOptionsToMatch[i])) {
+#if 0
+ if (i > 3 && AllTypeChecks) {
+ errs() << "FAILING TYPE #" << i << "\n";
+ NewOptionsToMatch[i]->dump();
+ }
+#endif
+ AllTypeChecks = false;
+ }
+ }
+ }
+
+ // If all the options are CheckOpcode's, we can form the SwitchOpcode, woot.
+ if (AllOpcodeChecks) {
+ StringSet<> Opcodes;
+ SmallVector<std::pair<const SDNodeInfo*, Matcher*>, 8> Cases;
+ for (unsigned i = 0, e = NewOptionsToMatch.size(); i != e; ++i) {
+ CheckOpcodeMatcher *COM = cast<CheckOpcodeMatcher>(NewOptionsToMatch[i]);
+ assert(Opcodes.insert(COM->getOpcode().getEnumName()) &&
+ "Duplicate opcodes not factored?");
+ Cases.push_back(std::make_pair(&COM->getOpcode(), COM->getNext()));
+ }
+
+ MatcherPtr.reset(new SwitchOpcodeMatcher(&Cases[0], Cases.size()));
+ return;
+ }
+
+ // If all the options are CheckType's, we can form the SwitchType, woot.
+ if (AllTypeChecks) {
+ DenseMap<unsigned, unsigned> TypeEntry;
+ SmallVector<std::pair<MVT::SimpleValueType, Matcher*>, 8> Cases;
+ for (unsigned i = 0, e = NewOptionsToMatch.size(); i != e; ++i) {
+ CheckTypeMatcher *CTM =
+ cast_or_null<CheckTypeMatcher>(FindNodeWithKind(NewOptionsToMatch[i],
+ Matcher::CheckType));
+ Matcher *MatcherWithoutCTM = NewOptionsToMatch[i]->unlinkNode(CTM);
+ MVT::SimpleValueType CTMTy = CTM->getType();
+ delete CTM;
+
+ unsigned &Entry = TypeEntry[CTMTy];
+ if (Entry != 0) {
+ // If we have unfactored duplicate types, then we should factor them.
+ Matcher *PrevMatcher = Cases[Entry-1].second;
+ if (ScopeMatcher *SM = dyn_cast<ScopeMatcher>(PrevMatcher)) {
+ SM->setNumChildren(SM->getNumChildren()+1);
+ SM->resetChild(SM->getNumChildren()-1, MatcherWithoutCTM);
+ continue;
+ }
+
+ Matcher *Entries[2] = { PrevMatcher, MatcherWithoutCTM };
+ Cases[Entry-1].second = new ScopeMatcher(Entries, 2);
+ continue;
+ }
+
+ Entry = Cases.size()+1;
+ Cases.push_back(std::make_pair(CTMTy, MatcherWithoutCTM));
+ }
+
+ if (Cases.size() != 1) {
+ MatcherPtr.reset(new SwitchTypeMatcher(&Cases[0], Cases.size()));
+ } else {
+ // If we factored and ended up with one case, create it now.
+ MatcherPtr.reset(new CheckTypeMatcher(Cases[0].first, 0));
+ MatcherPtr->setNext(Cases[0].second);
+ }
+ return;
+ }
+
+
+ // Reassemble the Scope node with the adjusted children.
+ Scope->setNumChildren(NewOptionsToMatch.size());
+ for (unsigned i = 0, e = NewOptionsToMatch.size(); i != e; ++i)
+ Scope->resetChild(i, NewOptionsToMatch[i]);
}
-Matcher *llvm::OptimizeMatcher(Matcher *TheMatcher) {
+Matcher *llvm::OptimizeMatcher(Matcher *TheMatcher,
+ const CodeGenDAGPatterns &CGP) {
OwningPtr<Matcher> MatcherPtr(TheMatcher);
- ContractNodes(MatcherPtr);
+ ContractNodes(MatcherPtr, CGP);
SinkPatternPredicates(MatcherPtr);
FactorNodes(MatcherPtr);
return MatcherPtr.take();