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-rw-r--r--lib/CodeGen/CodeGenPrepare.cpp457
1 files changed, 388 insertions, 69 deletions
diff --git a/lib/CodeGen/CodeGenPrepare.cpp b/lib/CodeGen/CodeGenPrepare.cpp
index e82a306..6aa60c6 100644
--- a/lib/CodeGen/CodeGenPrepare.cpp
+++ b/lib/CodeGen/CodeGenPrepare.cpp
@@ -13,7 +13,6 @@
//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "codegenprepare"
#include "llvm/CodeGen/Passes.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallSet.h"
@@ -39,6 +38,7 @@
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
#include "llvm/Transforms/Utils/BypassSlowDivision.h"
@@ -46,6 +46,8 @@
using namespace llvm;
using namespace llvm::PatternMatch;
+#define DEBUG_TYPE "codegenprepare"
+
STATISTIC(NumBlocksElim, "Number of blocks eliminated");
STATISTIC(NumPHIsElim, "Number of trivial PHIs eliminated");
STATISTIC(NumGEPsElim, "Number of GEPs converted to casts");
@@ -70,6 +72,10 @@ static cl::opt<bool> DisableSelectToBranch(
"disable-cgp-select2branch", cl::Hidden, cl::init(false),
cl::desc("Disable select to branch conversion."));
+static cl::opt<bool> AddrSinkUsingGEPs(
+ "addr-sink-using-gep", cl::Hidden, cl::init(false),
+ cl::desc("Address sinking in CGP using GEPs."));
+
static cl::opt<bool> EnableAndCmpSinking(
"enable-andcmp-sinking", cl::Hidden, cl::init(true),
cl::desc("Enable sinkinig and/cmp into branches."));
@@ -111,8 +117,8 @@ typedef DenseMap<Instruction *, Type *> InstrToOrigTy;
public:
static char ID; // Pass identification, replacement for typeid
- explicit CodeGenPrepare(const TargetMachine *TM = 0)
- : FunctionPass(ID), TM(TM), TLI(0) {
+ explicit CodeGenPrepare(const TargetMachine *TM = nullptr)
+ : FunctionPass(ID), TM(TM), TLI(nullptr) {
initializeCodeGenPreparePass(*PassRegistry::getPassRegistry());
}
bool runOnFunction(Function &F) override;
@@ -177,7 +183,7 @@ bool CodeGenPrepare::runOnFunction(Function &F) {
TLInfo = &getAnalysis<TargetLibraryInfo>();
DominatorTreeWrapperPass *DTWP =
getAnalysisIfAvailable<DominatorTreeWrapperPass>();
- DT = DTWP ? &DTWP->getDomTree() : 0;
+ DT = DTWP ? &DTWP->getDomTree() : nullptr;
OptSize = F.getAttributes().hasAttribute(AttributeSet::FunctionIndex,
Attribute::OptimizeForSize);
@@ -623,6 +629,187 @@ static bool OptimizeCmpExpression(CmpInst *CI) {
return MadeChange;
}
+/// isExtractBitsCandidateUse - Check if the candidates could
+/// be combined with shift instruction, which includes:
+/// 1. Truncate instruction
+/// 2. And instruction and the imm is a mask of the low bits:
+/// imm & (imm+1) == 0
+static bool isExtractBitsCandidateUse(Instruction *User) {
+ if (!isa<TruncInst>(User)) {
+ if (User->getOpcode() != Instruction::And ||
+ !isa<ConstantInt>(User->getOperand(1)))
+ return false;
+
+ const APInt &Cimm = cast<ConstantInt>(User->getOperand(1))->getValue();
+
+ if ((Cimm & (Cimm + 1)).getBoolValue())
+ return false;
+ }
+ return true;
+}
+
+/// SinkShiftAndTruncate - sink both shift and truncate instruction
+/// to the use of truncate's BB.
+static bool
+SinkShiftAndTruncate(BinaryOperator *ShiftI, Instruction *User, ConstantInt *CI,
+ DenseMap<BasicBlock *, BinaryOperator *> &InsertedShifts,
+ const TargetLowering &TLI) {
+ BasicBlock *UserBB = User->getParent();
+ DenseMap<BasicBlock *, CastInst *> InsertedTruncs;
+ TruncInst *TruncI = dyn_cast<TruncInst>(User);
+ bool MadeChange = false;
+
+ for (Value::user_iterator TruncUI = TruncI->user_begin(),
+ TruncE = TruncI->user_end();
+ TruncUI != TruncE;) {
+
+ Use &TruncTheUse = TruncUI.getUse();
+ Instruction *TruncUser = cast<Instruction>(*TruncUI);
+ // Preincrement use iterator so we don't invalidate it.
+
+ ++TruncUI;
+
+ int ISDOpcode = TLI.InstructionOpcodeToISD(TruncUser->getOpcode());
+ if (!ISDOpcode)
+ continue;
+
+ // If the use is actually a legal node, there will not be an implicit
+ // truncate.
+ if (TLI.isOperationLegalOrCustom(ISDOpcode,
+ EVT::getEVT(TruncUser->getType())))
+ continue;
+
+ // Don't bother for PHI nodes.
+ if (isa<PHINode>(TruncUser))
+ continue;
+
+ BasicBlock *TruncUserBB = TruncUser->getParent();
+
+ if (UserBB == TruncUserBB)
+ continue;
+
+ BinaryOperator *&InsertedShift = InsertedShifts[TruncUserBB];
+ CastInst *&InsertedTrunc = InsertedTruncs[TruncUserBB];
+
+ if (!InsertedShift && !InsertedTrunc) {
+ BasicBlock::iterator InsertPt = TruncUserBB->getFirstInsertionPt();
+ // Sink the shift
+ if (ShiftI->getOpcode() == Instruction::AShr)
+ InsertedShift =
+ BinaryOperator::CreateAShr(ShiftI->getOperand(0), CI, "", InsertPt);
+ else
+ InsertedShift =
+ BinaryOperator::CreateLShr(ShiftI->getOperand(0), CI, "", InsertPt);
+
+ // Sink the trunc
+ BasicBlock::iterator TruncInsertPt = TruncUserBB->getFirstInsertionPt();
+ TruncInsertPt++;
+
+ InsertedTrunc = CastInst::Create(TruncI->getOpcode(), InsertedShift,
+ TruncI->getType(), "", TruncInsertPt);
+
+ MadeChange = true;
+
+ TruncTheUse = InsertedTrunc;
+ }
+ }
+ return MadeChange;
+}
+
+/// OptimizeExtractBits - sink the shift *right* instruction into user blocks if
+/// the uses could potentially be combined with this shift instruction and
+/// generate BitExtract instruction. It will only be applied if the architecture
+/// supports BitExtract instruction. Here is an example:
+/// BB1:
+/// %x.extract.shift = lshr i64 %arg1, 32
+/// BB2:
+/// %x.extract.trunc = trunc i64 %x.extract.shift to i16
+/// ==>
+///
+/// BB2:
+/// %x.extract.shift.1 = lshr i64 %arg1, 32
+/// %x.extract.trunc = trunc i64 %x.extract.shift.1 to i16
+///
+/// CodeGen will recoginze the pattern in BB2 and generate BitExtract
+/// instruction.
+/// Return true if any changes are made.
+static bool OptimizeExtractBits(BinaryOperator *ShiftI, ConstantInt *CI,
+ const TargetLowering &TLI) {
+ BasicBlock *DefBB = ShiftI->getParent();
+
+ /// Only insert instructions in each block once.
+ DenseMap<BasicBlock *, BinaryOperator *> InsertedShifts;
+
+ bool shiftIsLegal = TLI.isTypeLegal(TLI.getValueType(ShiftI->getType()));
+
+ bool MadeChange = false;
+ for (Value::user_iterator UI = ShiftI->user_begin(), E = ShiftI->user_end();
+ UI != E;) {
+ Use &TheUse = UI.getUse();
+ Instruction *User = cast<Instruction>(*UI);
+ // Preincrement use iterator so we don't invalidate it.
+ ++UI;
+
+ // Don't bother for PHI nodes.
+ if (isa<PHINode>(User))
+ continue;
+
+ if (!isExtractBitsCandidateUse(User))
+ continue;
+
+ BasicBlock *UserBB = User->getParent();
+
+ if (UserBB == DefBB) {
+ // If the shift and truncate instruction are in the same BB. The use of
+ // the truncate(TruncUse) may still introduce another truncate if not
+ // legal. In this case, we would like to sink both shift and truncate
+ // instruction to the BB of TruncUse.
+ // for example:
+ // BB1:
+ // i64 shift.result = lshr i64 opnd, imm
+ // trunc.result = trunc shift.result to i16
+ //
+ // BB2:
+ // ----> We will have an implicit truncate here if the architecture does
+ // not have i16 compare.
+ // cmp i16 trunc.result, opnd2
+ //
+ if (isa<TruncInst>(User) && shiftIsLegal
+ // If the type of the truncate is legal, no trucate will be
+ // introduced in other basic blocks.
+ && (!TLI.isTypeLegal(TLI.getValueType(User->getType()))))
+ MadeChange =
+ SinkShiftAndTruncate(ShiftI, User, CI, InsertedShifts, TLI);
+
+ continue;
+ }
+ // If we have already inserted a shift into this block, use it.
+ BinaryOperator *&InsertedShift = InsertedShifts[UserBB];
+
+ if (!InsertedShift) {
+ BasicBlock::iterator InsertPt = UserBB->getFirstInsertionPt();
+
+ if (ShiftI->getOpcode() == Instruction::AShr)
+ InsertedShift =
+ BinaryOperator::CreateAShr(ShiftI->getOperand(0), CI, "", InsertPt);
+ else
+ InsertedShift =
+ BinaryOperator::CreateLShr(ShiftI->getOperand(0), CI, "", InsertPt);
+
+ MadeChange = true;
+ }
+
+ // Replace a use of the shift with a use of the new shift.
+ TheUse = InsertedShift;
+ }
+
+ // If we removed all uses, nuke the shift.
+ if (ShiftI->use_empty())
+ ShiftI->eraseFromParent();
+
+ return MadeChange;
+}
+
namespace {
class CodeGenPrepareFortifiedLibCalls : public SimplifyFortifiedLibCalls {
protected:
@@ -671,8 +858,9 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
// happens.
WeakVH IterHandle(CurInstIterator);
- replaceAndRecursivelySimplify(CI, RetVal, TLI ? TLI->getDataLayout() : 0,
- TLInfo, ModifiedDT ? 0 : DT);
+ replaceAndRecursivelySimplify(CI, RetVal,
+ TLI ? TLI->getDataLayout() : nullptr,
+ TLInfo, ModifiedDT ? nullptr : DT);
// If the iterator instruction was recursively deleted, start over at the
// start of the block.
@@ -693,10 +881,10 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
}
// From here on out we're working with named functions.
- if (CI->getCalledFunction() == 0) return false;
+ if (!CI->getCalledFunction()) return false;
// We'll need DataLayout from here on out.
- const DataLayout *TD = TLI ? TLI->getDataLayout() : 0;
+ const DataLayout *TD = TLI ? TLI->getDataLayout() : nullptr;
if (!TD) return false;
// Lower all default uses of _chk calls. This is very similar
@@ -746,8 +934,8 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(BasicBlock *BB) {
if (!RI)
return false;
- PHINode *PN = 0;
- BitCastInst *BCI = 0;
+ PHINode *PN = nullptr;
+ BitCastInst *BCI = nullptr;
Value *V = RI->getReturnValue();
if (V) {
BCI = dyn_cast<BitCastInst>(V);
@@ -862,7 +1050,7 @@ namespace {
struct ExtAddrMode : public TargetLowering::AddrMode {
Value *BaseReg;
Value *ScaledReg;
- ExtAddrMode() : BaseReg(0), ScaledReg(0) {}
+ ExtAddrMode() : BaseReg(nullptr), ScaledReg(nullptr) {}
void print(raw_ostream &OS) const;
void dump() const;
@@ -1189,10 +1377,10 @@ class TypePromotionTransaction {
public:
/// \brief Remove all reference of \p Inst and optinally replace all its
/// uses with New.
- /// \pre If !Inst->use_empty(), then New != NULL
- InstructionRemover(Instruction *Inst, Value *New = NULL)
+ /// \pre If !Inst->use_empty(), then New != nullptr
+ InstructionRemover(Instruction *Inst, Value *New = nullptr)
: TypePromotionAction(Inst), Inserter(Inst), Hider(Inst),
- Replacer(NULL) {
+ Replacer(nullptr) {
if (New)
Replacer = new UsesReplacer(Inst, New);
DEBUG(dbgs() << "Do: InstructionRemover: " << *Inst << "\n");
@@ -1232,7 +1420,7 @@ public:
/// Same as Instruction::setOperand.
void setOperand(Instruction *Inst, unsigned Idx, Value *NewVal);
/// Same as Instruction::eraseFromParent.
- void eraseInstruction(Instruction *Inst, Value *NewVal = NULL);
+ void eraseInstruction(Instruction *Inst, Value *NewVal = nullptr);
/// Same as Value::replaceAllUsesWith.
void replaceAllUsesWith(Instruction *Inst, Value *New);
/// Same as Value::mutateType.
@@ -1245,84 +1433,75 @@ public:
void moveBefore(Instruction *Inst, Instruction *Before);
/// @}
- ~TypePromotionTransaction();
-
private:
/// The ordered list of actions made so far.
- SmallVector<TypePromotionAction *, 16> Actions;
- typedef SmallVectorImpl<TypePromotionAction *>::iterator CommitPt;
+ SmallVector<std::unique_ptr<TypePromotionAction>, 16> Actions;
+ typedef SmallVectorImpl<std::unique_ptr<TypePromotionAction>>::iterator CommitPt;
};
void TypePromotionTransaction::setOperand(Instruction *Inst, unsigned Idx,
Value *NewVal) {
Actions.push_back(
- new TypePromotionTransaction::OperandSetter(Inst, Idx, NewVal));
+ make_unique<TypePromotionTransaction::OperandSetter>(Inst, Idx, NewVal));
}
void TypePromotionTransaction::eraseInstruction(Instruction *Inst,
Value *NewVal) {
Actions.push_back(
- new TypePromotionTransaction::InstructionRemover(Inst, NewVal));
+ make_unique<TypePromotionTransaction::InstructionRemover>(Inst, NewVal));
}
void TypePromotionTransaction::replaceAllUsesWith(Instruction *Inst,
Value *New) {
- Actions.push_back(new TypePromotionTransaction::UsesReplacer(Inst, New));
+ Actions.push_back(make_unique<TypePromotionTransaction::UsesReplacer>(Inst, New));
}
void TypePromotionTransaction::mutateType(Instruction *Inst, Type *NewTy) {
- Actions.push_back(new TypePromotionTransaction::TypeMutator(Inst, NewTy));
+ Actions.push_back(make_unique<TypePromotionTransaction::TypeMutator>(Inst, NewTy));
}
Instruction *TypePromotionTransaction::createTrunc(Instruction *Opnd,
Type *Ty) {
- TruncBuilder *TB = new TruncBuilder(Opnd, Ty);
- Actions.push_back(TB);
- return TB->getBuiltInstruction();
+ std::unique_ptr<TruncBuilder> Ptr(new TruncBuilder(Opnd, Ty));
+ Instruction *I = Ptr->getBuiltInstruction();
+ Actions.push_back(std::move(Ptr));
+ return I;
}
Instruction *TypePromotionTransaction::createSExt(Instruction *Inst,
Value *Opnd, Type *Ty) {
- SExtBuilder *SB = new SExtBuilder(Inst, Opnd, Ty);
- Actions.push_back(SB);
- return SB->getBuiltInstruction();
+ std::unique_ptr<SExtBuilder> Ptr(new SExtBuilder(Inst, Opnd, Ty));
+ Instruction *I = Ptr->getBuiltInstruction();
+ Actions.push_back(std::move(Ptr));
+ return I;
}
void TypePromotionTransaction::moveBefore(Instruction *Inst,
Instruction *Before) {
Actions.push_back(
- new TypePromotionTransaction::InstructionMoveBefore(Inst, Before));
+ make_unique<TypePromotionTransaction::InstructionMoveBefore>(Inst, Before));
}
TypePromotionTransaction::ConstRestorationPt
TypePromotionTransaction::getRestorationPoint() const {
- return Actions.rbegin() != Actions.rend() ? *Actions.rbegin() : NULL;
+ return !Actions.empty() ? Actions.back().get() : nullptr;
}
void TypePromotionTransaction::commit() {
for (CommitPt It = Actions.begin(), EndIt = Actions.end(); It != EndIt;
- ++It) {
+ ++It)
(*It)->commit();
- delete *It;
- }
Actions.clear();
}
void TypePromotionTransaction::rollback(
TypePromotionTransaction::ConstRestorationPt Point) {
- while (!Actions.empty() && Point != (*Actions.rbegin())) {
- TypePromotionAction *Curr = Actions.pop_back_val();
+ while (!Actions.empty() && Point != Actions.back().get()) {
+ std::unique_ptr<TypePromotionAction> Curr = Actions.pop_back_val();
Curr->undo();
- delete Curr;
}
}
-TypePromotionTransaction::~TypePromotionTransaction() {
- for (CommitPt It = Actions.begin(), EndIt = Actions.end(); It != EndIt; ++It)
- delete *It;
- Actions.clear();
-}
-
/// \brief A helper class for matching addressing modes.
///
/// This encapsulates the logic for matching the target-legal addressing modes.
@@ -1390,7 +1569,7 @@ private:
bool MatchScaledValue(Value *ScaleReg, int64_t Scale, unsigned Depth);
bool MatchAddr(Value *V, unsigned Depth);
bool MatchOperationAddr(User *Operation, unsigned Opcode, unsigned Depth,
- bool *MovedAway = NULL);
+ bool *MovedAway = nullptr);
bool IsProfitableToFoldIntoAddressingMode(Instruction *I,
ExtAddrMode &AMBefore,
ExtAddrMode &AMAfter);
@@ -1435,7 +1614,7 @@ bool AddressingModeMatcher::MatchScaledValue(Value *ScaleReg, int64_t Scale,
// Okay, we decided that we can add ScaleReg+Scale to AddrMode. Check now
// to see if ScaleReg is actually X+C. If so, we can turn this into adding
// X*Scale + C*Scale to addr mode.
- ConstantInt *CI = 0; Value *AddLHS = 0;
+ ConstantInt *CI = nullptr; Value *AddLHS = nullptr;
if (isa<Instruction>(ScaleReg) && // not a constant expr.
match(ScaleReg, m_Add(m_Value(AddLHS), m_ConstantInt(CI)))) {
TestAddrMode.ScaledReg = AddLHS;
@@ -1461,6 +1640,7 @@ bool AddressingModeMatcher::MatchScaledValue(Value *ScaleReg, int64_t Scale,
static bool MightBeFoldableInst(Instruction *I) {
switch (I->getOpcode()) {
case Instruction::BitCast:
+ case Instruction::AddrSpaceCast:
// Don't touch identity bitcasts.
if (I->getType() == I->getOperand(0)->getType())
return false;
@@ -1612,13 +1792,13 @@ TypePromotionHelper::Action TypePromotionHelper::getAction(
// get through.
// If it, check we can get through.
if (!SExtOpnd || !canGetThrough(SExtOpnd, SExtTy, PromotedInsts))
- return NULL;
+ return nullptr;
// Do not promote if the operand has been added by codegenprepare.
// Otherwise, it means we are undoing an optimization that is likely to be
// redone, thus causing potential infinite loop.
if (isa<TruncInst>(SExtOpnd) && InsertedTruncs.count(SExtOpnd))
- return NULL;
+ return nullptr;
// SExt or Trunc instructions.
// Return the related handler.
@@ -1629,7 +1809,7 @@ TypePromotionHelper::Action TypePromotionHelper::getAction(
// Abort early if we will have to insert non-free instructions.
if (!SExtOpnd->hasOneUse() &&
!TLI.isTruncateFree(SExtTy, SExtOpnd->getType()))
- return NULL;
+ return nullptr;
return promoteOperandForOther;
}
@@ -1740,7 +1920,7 @@ TypePromotionHelper::promoteOperandForOther(Instruction *SExt,
TPT.moveBefore(SExtForOpnd, SExtOpnd);
TPT.setOperand(SExtOpnd, OpIdx, SExtForOpnd);
// If more sext are required, new instructions will have to be created.
- SExtForOpnd = NULL;
+ SExtForOpnd = nullptr;
}
if (SExtForOpnd == SExt) {
DEBUG(dbgs() << "Sign extension is useless now\n");
@@ -1815,6 +1995,7 @@ bool AddressingModeMatcher::MatchOperationAddr(User *AddrInst, unsigned Opcode,
return MatchAddr(AddrInst->getOperand(0), Depth);
return false;
case Instruction::BitCast:
+ case Instruction::AddrSpaceCast:
// BitCast is always a noop, and we can handle it as long as it is
// int->int or pointer->pointer (we don't want int<->fp or something).
if ((AddrInst->getOperand(0)->getType()->isPointerTy() ||
@@ -2022,11 +2203,11 @@ bool AddressingModeMatcher::MatchAddr(Value *Addr, unsigned Depth) {
AddrMode.BaseOffs -= CI->getSExtValue();
} else if (GlobalValue *GV = dyn_cast<GlobalValue>(Addr)) {
// If this is a global variable, try to fold it into the addressing mode.
- if (AddrMode.BaseGV == 0) {
+ if (!AddrMode.BaseGV) {
AddrMode.BaseGV = GV;
if (TLI.isLegalAddressingMode(AddrMode, AccessTy))
return true;
- AddrMode.BaseGV = 0;
+ AddrMode.BaseGV = nullptr;
}
} else if (Instruction *I = dyn_cast<Instruction>(Addr)) {
ExtAddrMode BackupAddrMode = AddrMode;
@@ -2071,7 +2252,7 @@ bool AddressingModeMatcher::MatchAddr(Value *Addr, unsigned Depth) {
if (TLI.isLegalAddressingMode(AddrMode, AccessTy))
return true;
AddrMode.HasBaseReg = false;
- AddrMode.BaseReg = 0;
+ AddrMode.BaseReg = nullptr;
}
// If the base register is already taken, see if we can do [r+r].
@@ -2081,7 +2262,7 @@ bool AddressingModeMatcher::MatchAddr(Value *Addr, unsigned Depth) {
if (TLI.isLegalAddressingMode(AddrMode, AccessTy))
return true;
AddrMode.Scale = 0;
- AddrMode.ScaledReg = 0;
+ AddrMode.ScaledReg = nullptr;
}
// Couldn't match.
TPT.rollback(LastKnownGood);
@@ -2166,7 +2347,7 @@ static bool FindAllMemoryUses(Instruction *I,
bool AddressingModeMatcher::ValueAlreadyLiveAtInst(Value *Val,Value *KnownLive1,
Value *KnownLive2) {
// If Val is either of the known-live values, we know it is live!
- if (Val == 0 || Val == KnownLive1 || Val == KnownLive2)
+ if (Val == nullptr || Val == KnownLive1 || Val == KnownLive2)
return true;
// All values other than instructions and arguments (e.g. constants) are live.
@@ -2225,13 +2406,13 @@ IsProfitableToFoldIntoAddressingMode(Instruction *I, ExtAddrMode &AMBefore,
// If the BaseReg or ScaledReg was referenced by the previous addrmode, their
// lifetime wasn't extended by adding this instruction.
if (ValueAlreadyLiveAtInst(BaseReg, AMBefore.BaseReg, AMBefore.ScaledReg))
- BaseReg = 0;
+ BaseReg = nullptr;
if (ValueAlreadyLiveAtInst(ScaledReg, AMBefore.BaseReg, AMBefore.ScaledReg))
- ScaledReg = 0;
+ ScaledReg = nullptr;
// If folding this instruction (and it's subexprs) didn't extend any live
// ranges, we're ok with it.
- if (BaseReg == 0 && ScaledReg == 0)
+ if (!BaseReg && !ScaledReg)
return true;
// If all uses of this instruction are ultimately load/store/inlineasm's,
@@ -2320,7 +2501,7 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
// Use a worklist to iteratively look through PHI nodes, and ensure that
// the addressing mode obtained from the non-PHI roots of the graph
// are equivalent.
- Value *Consensus = 0;
+ Value *Consensus = nullptr;
unsigned NumUsesConsensus = 0;
bool IsNumUsesConsensusValid = false;
SmallVector<Instruction*, 16> AddrModeInsts;
@@ -2334,7 +2515,7 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
// Break use-def graph loops.
if (!Visited.insert(V)) {
- Consensus = 0;
+ Consensus = nullptr;
break;
}
@@ -2380,7 +2561,7 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
continue;
}
- Consensus = 0;
+ Consensus = nullptr;
break;
}
@@ -2420,14 +2601,135 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
Value *&SunkAddr = SunkAddrs[Addr];
if (SunkAddr) {
DEBUG(dbgs() << "CGP: Reusing nonlocal addrmode: " << AddrMode << " for "
- << *MemoryInst);
+ << *MemoryInst << "\n");
if (SunkAddr->getType() != Addr->getType())
SunkAddr = Builder.CreateBitCast(SunkAddr, Addr->getType());
+ } else if (AddrSinkUsingGEPs || (!AddrSinkUsingGEPs.getNumOccurrences() &&
+ TM && TM->getSubtarget<TargetSubtargetInfo>().useAA())) {
+ // By default, we use the GEP-based method when AA is used later. This
+ // prevents new inttoptr/ptrtoint pairs from degrading AA capabilities.
+ DEBUG(dbgs() << "CGP: SINKING nonlocal addrmode: " << AddrMode << " for "
+ << *MemoryInst << "\n");
+ Type *IntPtrTy = TLI->getDataLayout()->getIntPtrType(Addr->getType());
+ Value *ResultPtr = nullptr, *ResultIndex = nullptr;
+
+ // First, find the pointer.
+ if (AddrMode.BaseReg && AddrMode.BaseReg->getType()->isPointerTy()) {
+ ResultPtr = AddrMode.BaseReg;
+ AddrMode.BaseReg = nullptr;
+ }
+
+ if (AddrMode.Scale && AddrMode.ScaledReg->getType()->isPointerTy()) {
+ // We can't add more than one pointer together, nor can we scale a
+ // pointer (both of which seem meaningless).
+ if (ResultPtr || AddrMode.Scale != 1)
+ return false;
+
+ ResultPtr = AddrMode.ScaledReg;
+ AddrMode.Scale = 0;
+ }
+
+ if (AddrMode.BaseGV) {
+ if (ResultPtr)
+ return false;
+
+ ResultPtr = AddrMode.BaseGV;
+ }
+
+ // If the real base value actually came from an inttoptr, then the matcher
+ // will look through it and provide only the integer value. In that case,
+ // use it here.
+ if (!ResultPtr && AddrMode.BaseReg) {
+ ResultPtr =
+ Builder.CreateIntToPtr(AddrMode.BaseReg, Addr->getType(), "sunkaddr");
+ AddrMode.BaseReg = nullptr;
+ } else if (!ResultPtr && AddrMode.Scale == 1) {
+ ResultPtr =
+ Builder.CreateIntToPtr(AddrMode.ScaledReg, Addr->getType(), "sunkaddr");
+ AddrMode.Scale = 0;
+ }
+
+ if (!ResultPtr &&
+ !AddrMode.BaseReg && !AddrMode.Scale && !AddrMode.BaseOffs) {
+ SunkAddr = Constant::getNullValue(Addr->getType());
+ } else if (!ResultPtr) {
+ return false;
+ } else {
+ Type *I8PtrTy =
+ Builder.getInt8PtrTy(Addr->getType()->getPointerAddressSpace());
+
+ // Start with the base register. Do this first so that subsequent address
+ // matching finds it last, which will prevent it from trying to match it
+ // as the scaled value in case it happens to be a mul. That would be
+ // problematic if we've sunk a different mul for the scale, because then
+ // we'd end up sinking both muls.
+ if (AddrMode.BaseReg) {
+ Value *V = AddrMode.BaseReg;
+ if (V->getType() != IntPtrTy)
+ V = Builder.CreateIntCast(V, IntPtrTy, /*isSigned=*/true, "sunkaddr");
+
+ ResultIndex = V;
+ }
+
+ // Add the scale value.
+ if (AddrMode.Scale) {
+ Value *V = AddrMode.ScaledReg;
+ if (V->getType() == IntPtrTy) {
+ // done.
+ } else if (cast<IntegerType>(IntPtrTy)->getBitWidth() <
+ cast<IntegerType>(V->getType())->getBitWidth()) {
+ V = Builder.CreateTrunc(V, IntPtrTy, "sunkaddr");
+ } else {
+ // It is only safe to sign extend the BaseReg if we know that the math
+ // required to create it did not overflow before we extend it. Since
+ // the original IR value was tossed in favor of a constant back when
+ // the AddrMode was created we need to bail out gracefully if widths
+ // do not match instead of extending it.
+ Instruction *I = dyn_cast_or_null<Instruction>(ResultIndex);
+ if (I && (ResultIndex != AddrMode.BaseReg))
+ I->eraseFromParent();
+ return false;
+ }
+
+ if (AddrMode.Scale != 1)
+ V = Builder.CreateMul(V, ConstantInt::get(IntPtrTy, AddrMode.Scale),
+ "sunkaddr");
+ if (ResultIndex)
+ ResultIndex = Builder.CreateAdd(ResultIndex, V, "sunkaddr");
+ else
+ ResultIndex = V;
+ }
+
+ // Add in the Base Offset if present.
+ if (AddrMode.BaseOffs) {
+ Value *V = ConstantInt::get(IntPtrTy, AddrMode.BaseOffs);
+ if (ResultIndex) {
+ // We need to add this separately from the scale above to help with
+ // SDAG consecutive load/store merging.
+ if (ResultPtr->getType() != I8PtrTy)
+ ResultPtr = Builder.CreateBitCast(ResultPtr, I8PtrTy);
+ ResultPtr = Builder.CreateGEP(ResultPtr, ResultIndex, "sunkaddr");
+ }
+
+ ResultIndex = V;
+ }
+
+ if (!ResultIndex) {
+ SunkAddr = ResultPtr;
+ } else {
+ if (ResultPtr->getType() != I8PtrTy)
+ ResultPtr = Builder.CreateBitCast(ResultPtr, I8PtrTy);
+ SunkAddr = Builder.CreateGEP(ResultPtr, ResultIndex, "sunkaddr");
+ }
+
+ if (SunkAddr->getType() != Addr->getType())
+ SunkAddr = Builder.CreateBitCast(SunkAddr, Addr->getType());
+ }
} else {
DEBUG(dbgs() << "CGP: SINKING nonlocal addrmode: " << AddrMode << " for "
- << *MemoryInst);
+ << *MemoryInst << "\n");
Type *IntPtrTy = TLI->getDataLayout()->getIntPtrType(Addr->getType());
- Value *Result = 0;
+ Value *Result = nullptr;
// Start with the base register. Do this first so that subsequent address
// matching finds it last, which will prevent it from trying to match it
@@ -2459,8 +2761,9 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
// the original IR value was tossed in favor of a constant back when
// the AddrMode was created we need to bail out gracefully if widths
// do not match instead of extending it.
- if (Result != AddrMode.BaseReg)
- cast<Instruction>(Result)->eraseFromParent();
+ Instruction *I = dyn_cast_or_null<Instruction>(Result);
+ if (I && (Result != AddrMode.BaseReg))
+ I->eraseFromParent();
return false;
}
if (AddrMode.Scale != 1)
@@ -2490,7 +2793,7 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
Result = V;
}
- if (Result == 0)
+ if (!Result)
SunkAddr = Constant::getNullValue(Addr->getType());
else
SunkAddr = Builder.CreateIntToPtr(Result, Addr->getType(), "sunkaddr");
@@ -2815,7 +3118,7 @@ bool CodeGenPrepare::OptimizeInst(Instruction *I) {
// It is possible for very late stage optimizations (such as SimplifyCFG)
// to introduce PHI nodes too late to be cleaned up. If we detect such a
// trivial PHI, go ahead and zap it here.
- if (Value *V = SimplifyInstruction(P, TLI ? TLI->getDataLayout() : 0,
+ if (Value *V = SimplifyInstruction(P, TLI ? TLI->getDataLayout() : nullptr,
TLInfo, DT)) {
P->replaceAllUsesWith(V);
P->eraseFromParent();
@@ -2870,6 +3173,17 @@ bool CodeGenPrepare::OptimizeInst(Instruction *I) {
return false;
}
+ BinaryOperator *BinOp = dyn_cast<BinaryOperator>(I);
+
+ if (BinOp && (BinOp->getOpcode() == Instruction::AShr ||
+ BinOp->getOpcode() == Instruction::LShr)) {
+ ConstantInt *CI = dyn_cast<ConstantInt>(BinOp->getOperand(1));
+ if (TLI && CI && TLI->hasExtractBitsInsn())
+ return OptimizeExtractBits(BinOp, CI, *TLI);
+
+ return false;
+ }
+
if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(I)) {
if (GEPI->hasAllZeroIndices()) {
/// The GEP operand must be a pointer, so must its result -> BitCast
@@ -2918,11 +3232,16 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
bool CodeGenPrepare::PlaceDbgValues(Function &F) {
bool MadeChange = false;
for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I) {
- Instruction *PrevNonDbgInst = NULL;
+ Instruction *PrevNonDbgInst = nullptr;
for (BasicBlock::iterator BI = I->begin(), BE = I->end(); BI != BE;) {
Instruction *Insn = BI; ++BI;
DbgValueInst *DVI = dyn_cast<DbgValueInst>(Insn);
- if (!DVI) {
+ // Leave dbg.values that refer to an alloca alone. These
+ // instrinsics describe the address of a variable (= the alloca)
+ // being taken. They should not be moved next to the alloca
+ // (and to the beginning of the scope), but rather stay close to
+ // where said address is used.
+ if (!DVI || (DVI->getValue() && isa<AllocaInst>(DVI->getValue()))) {
PrevNonDbgInst = Insn;
continue;
}
generated by cgit v1.1 at 2025-05-14 22:55:59 +0000