#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
-#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/DIBuilder.h"
-#include "llvm/DebugInfo.h"
+#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
+#include "llvm/IR/DIBuilder.h"
#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Operator.h"
-#include "llvm/Support/CFG.h"
+#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/Debug.h"
-#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/MathExtras.h"
-#include "llvm/Support/ValueHandle.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
+#define DEBUG_TYPE "local"
+
STATISTIC(NumRemoved, "Number of unreachable basic blocks removed");
//===----------------------------------------------------------------------===//
// dest. If so, eliminate it as an explicit compare.
if (i.getCaseSuccessor() == DefaultDest) {
MDNode* MD = SI->getMetadata(LLVMContext::MD_prof);
- // MD should have 2 + NumCases operands.
- if (MD && MD->getNumOperands() == 2 + SI->getNumCases()) {
+ unsigned NCases = SI->getNumCases();
+ // Fold the case metadata into the default if there will be any branches
+ // left, unless the metadata doesn't match the switch.
+ if (NCases > 1 && MD && MD->getNumOperands() == 2 + NCases) {
// Collect branch weights into a vector.
SmallVector<uint32_t, 8> Weights;
for (unsigned MD_i = 1, MD_e = MD->getNumOperands(); MD_i < MD_e;
// Otherwise, check to see if the switch only branches to one destination.
// We do this by reseting "TheOnlyDest" to null when we find two non-equal
// destinations.
- if (i.getCaseSuccessor() != TheOnlyDest) TheOnlyDest = 0;
+ if (i.getCaseSuccessor() != TheOnlyDest) TheOnlyDest = nullptr;
}
if (CI && !TheOnlyDest) {
// Found case matching a constant operand?
BasicBlock *Succ = SI->getSuccessor(i);
if (Succ == TheOnlyDest)
- TheOnlyDest = 0; // Don't modify the first branch to TheOnlyDest
+ TheOnlyDest = nullptr; // Don't modify the first branch to TheOnlyDest
else
Succ->removePredecessor(BB);
}
for (unsigned i = 0, e = IBI->getNumDestinations(); i != e; ++i) {
if (IBI->getDestination(i) == TheOnlyDest)
- TheOnlyDest = 0;
+ TheOnlyDest = nullptr;
else
IBI->getDestination(i)->removePredecessor(IBI->getParent());
}
if (II->getIntrinsicID() == Intrinsic::lifetime_start ||
II->getIntrinsicID() == Intrinsic::lifetime_end)
return isa<UndefValue>(II->getArgOperand(1));
+
+ // Assumptions are dead if their condition is trivially true.
+ if (II->getIntrinsicID() == Intrinsic::assume) {
+ if (ConstantInt *Cond = dyn_cast<ConstantInt>(II->getArgOperand(0)))
+ return !Cond->isZero();
+
+ return false;
+ }
}
if (isAllocLikeFn(I, TLI)) return true;
// dead as we go.
for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
Value *OpV = I->getOperand(i);
- I->setOperand(i, 0);
+ I->setOperand(i, nullptr);
if (!OpV->use_empty()) continue;
/// true when there are no uses or multiple uses that all refer to the same
/// value.
static bool areAllUsesEqual(Instruction *I) {
- Value::use_iterator UI = I->use_begin();
- Value::use_iterator UE = I->use_end();
+ Value::user_iterator UI = I->user_begin();
+ Value::user_iterator UE = I->user_end();
if (UI == UE)
return true;
const TargetLibraryInfo *TLI) {
SmallPtrSet<Instruction*, 4> Visited;
for (Instruction *I = PN; areAllUsesEqual(I) && !I->mayHaveSideEffects();
- I = cast<Instruction>(*I->use_begin())) {
+ I = cast<Instruction>(*I->user_begin())) {
if (I->use_empty())
return RecursivelyDeleteTriviallyDeadInstructions(I, TLI);
PredBB->getTerminator()->eraseFromParent();
DestBB->getInstList().splice(DestBB->begin(), PredBB->getInstList());
+ // If the PredBB is the entry block of the function, move DestBB up to
+ // become the entry block after we erase PredBB.
+ if (PredBB == &DestBB->getParent()->getEntryBlock())
+ DestBB->moveAfter(PredBB);
+
if (P) {
- DominatorTree *DT = P->getAnalysisIfAvailable<DominatorTree>();
- if (DT) {
- BasicBlock *PredBBIDom = DT->getNode(PredBB)->getIDom()->getBlock();
- DT->changeImmediateDominator(DestBB, PredBBIDom);
- DT->eraseNode(PredBB);
+ if (DominatorTreeWrapperPass *DTWP =
+ P->getAnalysisIfAvailable<DominatorTreeWrapperPass>()) {
+ DominatorTree &DT = DTWP->getDomTree();
+ BasicBlock *PredBBIDom = DT.getNode(PredBB)->getIDom()->getBlock();
+ DT.changeImmediateDominator(DestBB, PredBBIDom);
+ DT.eraseNode(PredBB);
}
}
// Nuke BB.
if (!Succ->getSinglePredecessor()) {
BasicBlock::iterator BBI = BB->begin();
while (isa<PHINode>(*BBI)) {
- for (Value::use_iterator UI = BBI->use_begin(), E = BBI->use_end();
- UI != E; ++UI) {
- if (PHINode* PN = dyn_cast<PHINode>(*UI)) {
- if (PN->getIncomingBlock(UI) != BB)
+ for (Use &U : BBI->uses()) {
+ if (PHINode* PN = dyn_cast<PHINode>(U.getUser())) {
+ if (PN->getIncomingBlock(U) != BB)
return false;
} else {
return false;
return PrefAlign;
}
- if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
+ if (auto *GO = dyn_cast<GlobalObject>(V)) {
// If there is a large requested alignment and we can, bump up the alignment
// of the global.
- if (GV->isDeclaration()) return Align;
+ if (GO->isDeclaration())
+ return Align;
// If the memory we set aside for the global may not be the memory used by
// the final program then it is impossible for us to reliably enforce the
// preferred alignment.
- if (GV->isWeakForLinker()) return Align;
+ if (GO->isWeakForLinker())
+ return Align;
- if (GV->getAlignment() >= PrefAlign)
- return GV->getAlignment();
+ if (GO->getAlignment() >= PrefAlign)
+ return GO->getAlignment();
// We can only increase the alignment of the global if it has no alignment
// specified or if it is not assigned a section. If it is assigned a
// section, the global could be densely packed with other objects in the
// section, increasing the alignment could cause padding issues.
- if (!GV->hasSection() || GV->getAlignment() == 0)
- GV->setAlignment(PrefAlign);
- return GV->getAlignment();
+ if (!GO->hasSection() || GO->getAlignment() == 0)
+ GO->setAlignment(PrefAlign);
+ return GO->getAlignment();
}
return Align;
unsigned BitWidth = DL ? DL->getPointerTypeSizeInBits(V->getType()) : 64;
APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
- ComputeMaskedBits(V, KnownZero, KnownOne, DL);
+ computeKnownBits(V, KnownZero, KnownOne, DL);
unsigned TrailZ = KnownZero.countTrailingOnes();
// Avoid trouble with ridiculously large TrailZ values, such as
if (LdStHasDebugValue(DIVar, SI))
return true;
- Instruction *DbgVal = NULL;
+ Instruction *DbgVal = nullptr;
// If an argument is zero extended then use argument directly. The ZExt
// may be zapped by an optimization pass in future.
- Argument *ExtendedArg = NULL;
+ Argument *ExtendedArg = nullptr;
if (ZExtInst *ZExt = dyn_cast<ZExtInst>(SI->getOperand(0)))
ExtendedArg = dyn_cast<Argument>(ZExt->getOperand(0));
if (SExtInst *SExt = dyn_cast<SExtInst>(SI->getOperand(0)))
DbgVal = Builder.insertDbgValueIntrinsic(ExtendedArg, 0, DIVar, SI);
else
DbgVal = Builder.insertDbgValueIntrinsic(SI->getOperand(0), 0, DIVar, SI);
-
- // Propagate any debug metadata from the store onto the dbg.value.
- DebugLoc SIDL = SI->getDebugLoc();
- if (!SIDL.isUnknown())
- DbgVal->setDebugLoc(SIDL);
- // Otherwise propagate debug metadata from dbg.declare.
- else
- DbgVal->setDebugLoc(DDI->getDebugLoc());
+ DbgVal->setDebugLoc(DDI->getDebugLoc());
return true;
}
Instruction *DbgVal =
Builder.insertDbgValueIntrinsic(LI->getOperand(0), 0,
DIVar, LI);
-
- // Propagate any debug metadata from the store onto the dbg.value.
- DebugLoc LIDL = LI->getDebugLoc();
- if (!LIDL.isUnknown())
- DbgVal->setDebugLoc(LIDL);
- // Otherwise propagate debug metadata from dbg.declare.
- else
- DbgVal->setDebugLoc(DDI->getDebugLoc());
+ DbgVal->setDebugLoc(DDI->getDebugLoc());
return true;
}
+/// Determine whether this alloca is either a VLA or an array.
+static bool isArray(AllocaInst *AI) {
+ return AI->isArrayAllocation() ||
+ AI->getType()->getElementType()->isArrayTy();
+}
+
/// LowerDbgDeclare - Lowers llvm.dbg.declare intrinsics into appropriate set
/// of llvm.dbg.value intrinsics.
bool llvm::LowerDbgDeclare(Function &F) {
DIBuilder DIB(*F.getParent());
SmallVector<DbgDeclareInst *, 4> Dbgs;
- for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI)
- for (BasicBlock::iterator BI = FI->begin(), BE = FI->end(); BI != BE; ++BI) {
- if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(BI))
+ for (auto &FI : F)
+ for (BasicBlock::iterator BI : FI)
+ if (auto DDI = dyn_cast<DbgDeclareInst>(BI))
Dbgs.push_back(DDI);
- }
+
if (Dbgs.empty())
return false;
- for (SmallVectorImpl<DbgDeclareInst *>::iterator I = Dbgs.begin(),
- E = Dbgs.end(); I != E; ++I) {
- DbgDeclareInst *DDI = *I;
+ for (auto &I : Dbgs) {
+ DbgDeclareInst *DDI = I;
AllocaInst *AI = dyn_cast_or_null<AllocaInst>(DDI->getAddress());
// If this is an alloca for a scalar variable, insert a dbg.value
// at each load and store to the alloca and erase the dbg.declare.
- if (AI && !AI->isArrayAllocation()) {
-
- // We only remove the dbg.declare intrinsic if all uses are
- // converted to dbg.value intrinsics.
- bool RemoveDDI = true;
- for (Value::use_iterator UI = AI->use_begin(), E = AI->use_end();
- UI != E; ++UI)
- if (StoreInst *SI = dyn_cast<StoreInst>(*UI))
+ // The dbg.values allow tracking a variable even if it is not
+ // stored on the stack, while the dbg.declare can only describe
+ // the stack slot (and at a lexical-scope granularity). Later
+ // passes will attempt to elide the stack slot.
+ if (AI && !isArray(AI)) {
+ for (User *U : AI->users())
+ if (StoreInst *SI = dyn_cast<StoreInst>(U))
ConvertDebugDeclareToDebugValue(DDI, SI, DIB);
- else if (LoadInst *LI = dyn_cast<LoadInst>(*UI))
+ else if (LoadInst *LI = dyn_cast<LoadInst>(U))
ConvertDebugDeclareToDebugValue(DDI, LI, DIB);
- else
- RemoveDDI = false;
- if (RemoveDDI)
- DDI->eraseFromParent();
+ else if (CallInst *CI = dyn_cast<CallInst>(U)) {
+ // This is a call by-value or some other instruction that
+ // takes a pointer to the variable. Insert a *value*
+ // intrinsic that describes the alloca.
+ auto DbgVal =
+ DIB.insertDbgValueIntrinsic(AI, 0,
+ DIVariable(DDI->getVariable()), CI);
+ DbgVal->setDebugLoc(DDI->getDebugLoc());
+ }
+ DDI->eraseFromParent();
}
}
return true;
/// alloca 'V', if any.
DbgDeclareInst *llvm::FindAllocaDbgDeclare(Value *V) {
if (MDNode *DebugNode = MDNode::getIfExists(V->getContext(), V))
- for (Value::use_iterator UI = DebugNode->use_begin(),
- E = DebugNode->use_end(); UI != E; ++UI)
- if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(*UI))
+ for (User *U : DebugNode->users())
+ if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(U))
return DDI;
- return 0;
+ return nullptr;
}
bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
}
static bool markAliveBlocks(BasicBlock *BB,
- SmallPtrSet<BasicBlock*, 128> &Reachable) {
+ SmallPtrSetImpl<BasicBlock*> &Reachable) {
SmallVector<BasicBlock*, 128> Worklist;
Worklist.push_back(BB);
// instructions into LLVM unreachable insts. The instruction combining pass
// canonicalizes unreachable insts into stores to null or undef.
for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E;++BBI){
+ // Assumptions that are known to be false are equivalent to unreachable.
+ // Also, if the condition is undefined, then we make the choice most
+ // beneficial to the optimizer, and choose that to also be unreachable.
+ if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(BBI))
+ if (II->getIntrinsicID() == Intrinsic::assume) {
+ bool MakeUnreachable = false;
+ if (isa<UndefValue>(II->getArgOperand(0)))
+ MakeUnreachable = true;
+ else if (ConstantInt *Cond =
+ dyn_cast<ConstantInt>(II->getArgOperand(0)))
+ MakeUnreachable = Cond->isZero();
+
+ if (MakeUnreachable) {
+ // Don't insert a call to llvm.trap right before the unreachable.
+ changeToUnreachable(BBI, false);
+ Changed = true;
+ break;
+ }
+ }
+
if (CallInst *CI = dyn_cast<CallInst>(BBI)) {
if (CI->doesNotReturn()) {
// If we found a call to a no-return function, insert an unreachable
return true;
}
+
+void llvm::combineMetadata(Instruction *K, const Instruction *J, ArrayRef<unsigned> KnownIDs) {
+ SmallVector<std::pair<unsigned, MDNode*>, 4> Metadata;
+ K->dropUnknownMetadata(KnownIDs);
+ K->getAllMetadataOtherThanDebugLoc(Metadata);
+ for (unsigned i = 0, n = Metadata.size(); i < n; ++i) {
+ unsigned Kind = Metadata[i].first;
+ MDNode *JMD = J->getMetadata(Kind);
+ MDNode *KMD = Metadata[i].second;
+
+ switch (Kind) {
+ default:
+ K->setMetadata(Kind, nullptr); // Remove unknown metadata
+ break;
+ case LLVMContext::MD_dbg:
+ llvm_unreachable("getAllMetadataOtherThanDebugLoc returned a MD_dbg");
+ case LLVMContext::MD_tbaa:
+ K->setMetadata(Kind, MDNode::getMostGenericTBAA(JMD, KMD));
+ break;
+ case LLVMContext::MD_alias_scope:
+ case LLVMContext::MD_noalias:
+ K->setMetadata(Kind, MDNode::intersect(JMD, KMD));
+ break;
+ case LLVMContext::MD_range:
+ K->setMetadata(Kind, MDNode::getMostGenericRange(JMD, KMD));
+ break;
+ case LLVMContext::MD_fpmath:
+ K->setMetadata(Kind, MDNode::getMostGenericFPMath(JMD, KMD));
+ break;
+ case LLVMContext::MD_invariant_load:
+ // Only set the !invariant.load if it is present in both instructions.
+ K->setMetadata(Kind, JMD);
+ break;
+ }
+ }
+}
projects / oota-llvm.git / blobdiff