summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--llvm/include/llvm/Analysis/ScalarEvolution.h20
-rw-r--r--llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h6
-rw-r--r--llvm/include/llvm/Transforms/Utils/Local.h27
-rw-r--r--llvm/lib/Analysis/ScalarEvolution.cpp58
-rw-r--r--llvm/lib/Transforms/Scalar/IndVarSimplify.cpp2
-rw-r--r--llvm/lib/Transforms/Scalar/LoopDeletion.cpp7
-rw-r--r--llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp23
-rw-r--r--llvm/lib/Transforms/Utils/BasicBlockUtils.cpp7
-rw-r--r--llvm/lib/Transforms/Utils/Local.cpp21
9 files changed, 119 insertions, 52 deletions
diff --git a/llvm/include/llvm/Analysis/ScalarEvolution.h b/llvm/include/llvm/Analysis/ScalarEvolution.h
index 42b318dcf08..a0a7c1e81d2 100644
--- a/llvm/include/llvm/Analysis/ScalarEvolution.h
+++ b/llvm/include/llvm/Analysis/ScalarEvolution.h
@@ -24,7 +24,6 @@
#include "llvm/Pass.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Support/DataTypes.h"
-#include "llvm/Support/ValueHandle.h"
#include <iosfwd>
namespace llvm {
@@ -193,23 +192,11 @@ namespace llvm {
template<> struct simplify_type<SCEVHandle>
: public simplify_type<const SCEVHandle> {};
- /// SCEVCallbackVH - A CallbackVH to arrange for ScalarEvolution to be
- /// notified whenever a Value is deleted.
- class SCEVCallbackVH : public CallbackVH {
- ScalarEvolution *SE;
- virtual void deleted();
- virtual void allUsesReplacedWith(Value *V);
- public:
- SCEVCallbackVH(Value *V, ScalarEvolution *SE = 0);
- };
-
/// ScalarEvolution - This class is the main scalar evolution driver. Because
/// client code (intentionally) can't do much with the SCEV objects directly,
/// they must ask this class for services.
///
class ScalarEvolution : public FunctionPass {
- friend class SCEVCallbackVH;
-
/// F - The function we are analyzing.
///
Function *F;
@@ -228,7 +215,7 @@ namespace llvm {
/// Scalars - This is a cache of the scalars we have analyzed so far.
///
- std::map<SCEVCallbackVH, SCEVHandle> Scalars;
+ std::map<Value*, SCEVHandle> Scalars;
/// BackedgeTakenInfo - Information about the backedge-taken count
/// of a loop. This currently inclues an exact count and a maximum count.
@@ -500,6 +487,11 @@ namespace llvm {
/// is deleted.
void forgetLoopBackedgeTakenCount(const Loop *L);
+ /// deleteValueFromRecords - This method should be called by the
+ /// client before it removes a Value from the program, to make sure
+ /// that no dangling references are left around.
+ void deleteValueFromRecords(Value *V);
+
virtual bool runOnFunction(Function &F);
virtual void releaseMemory();
virtual void getAnalysisUsage(AnalysisUsage &AU) const;
diff --git a/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h b/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h
index 7dc2b94dc45..6105416a407 100644
--- a/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h
+++ b/llvm/include/llvm/Transforms/Utils/BasicBlockUtils.h
@@ -25,6 +25,7 @@ namespace llvm {
class Instruction;
class Pass;
class AliasAnalysis;
+class ValueDeletionListener;
/// DeleteDeadBlock - Delete the specified block, which must have no
/// predecessors.
@@ -40,8 +41,9 @@ void FoldSingleEntryPHINodes(BasicBlock *BB);
/// DeleteDeadPHIs - Examine each PHI in the given block and delete it if it
/// is dead. Also recursively delete any operands that become dead as
/// a result. This includes tracing the def-use list from the PHI to see if
-/// it is ultimately unused or if it reaches an unused cycle.
-void DeleteDeadPHIs(BasicBlock *BB);
+/// it is ultimately unused or if it reaches an unused cycle. If a
+/// ValueDeletionListener is specified, it is notified of the deletions.
+void DeleteDeadPHIs(BasicBlock *BB, ValueDeletionListener *VDL = 0);
/// MergeBlockIntoPredecessor - Attempts to merge a block into its predecessor,
/// if possible. The return value indicates success or failure.
diff --git a/llvm/include/llvm/Transforms/Utils/Local.h b/llvm/include/llvm/Transforms/Utils/Local.h
index 5ea1a500c59..4cb46b0c4b6 100644
--- a/llvm/include/llvm/Transforms/Utils/Local.h
+++ b/llvm/include/llvm/Transforms/Utils/Local.h
@@ -50,17 +50,40 @@ bool ConstantFoldTerminator(BasicBlock *BB);
///
bool isInstructionTriviallyDead(Instruction *I);
+/// ValueDeletionListener - A simple abstract interface for delivering
+/// notifications when Values are deleted.
+///
+/// @todo Consider whether ValueDeletionListener can be made obsolete by
+/// requiring clients to use CallbackVH instead.
+class ValueDeletionListener {
+public:
+ /// ValueWillBeDeleted - This method is called shortly before the specified
+ /// value will be deleted.
+ virtual void ValueWillBeDeleted(Value *V) = 0;
+
+protected:
+ virtual ~ValueDeletionListener();
+};
+
/// RecursivelyDeleteTriviallyDeadInstructions - If the specified value is a
/// trivially dead instruction, delete it. If that makes any of its operands
/// trivially dead, delete them too, recursively.
-void RecursivelyDeleteTriviallyDeadInstructions(Value *V);
+///
+/// If a ValueDeletionListener is specified, it is notified of instructions that
+/// are actually deleted (before they are actually deleted).
+void RecursivelyDeleteTriviallyDeadInstructions(Value *V,
+ ValueDeletionListener *VDL = 0);
/// RecursivelyDeleteDeadPHINode - If the specified value is an effectively
/// dead PHI node, due to being a def-use chain of single-use nodes that
/// either forms a cycle or is terminated by a trivially dead instruction,
/// delete it. If that makes any of its operands trivially dead, delete them
/// too, recursively.
-void RecursivelyDeleteDeadPHINode(PHINode *PN);
+///
+/// If a ValueDeletionListener is specified, it is notified of instructions that
+/// are actually deleted (before they are actually deleted).
+void RecursivelyDeleteDeadPHINode(PHINode *PN,
+ ValueDeletionListener *VDL = 0);
//===----------------------------------------------------------------------===//
// Control Flow Graph Restructuring.
diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 48a2f52612a..a6d39541aae 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -1466,6 +1466,34 @@ SCEVHandle ScalarEvolution::getUnknown(Value *V) {
// Basic SCEV Analysis and PHI Idiom Recognition Code
//
+/// deleteValueFromRecords - This method should be called by the
+/// client before it removes an instruction from the program, to make sure
+/// that no dangling references are left around.
+void ScalarEvolution::deleteValueFromRecords(Value *V) {
+ SmallVector<Value *, 16> Worklist;
+
+ if (Scalars.erase(V)) {
+ if (PHINode *PN = dyn_cast<PHINode>(V))
+ ConstantEvolutionLoopExitValue.erase(PN);
+ Worklist.push_back(V);
+ }
+
+ while (!Worklist.empty()) {
+ Value *VV = Worklist.back();
+ Worklist.pop_back();
+
+ for (Instruction::use_iterator UI = VV->use_begin(), UE = VV->use_end();
+ UI != UE; ++UI) {
+ Instruction *Inst = cast<Instruction>(*UI);
+ if (Scalars.erase(Inst)) {
+ if (PHINode *PN = dyn_cast<PHINode>(VV))
+ ConstantEvolutionLoopExitValue.erase(PN);
+ Worklist.push_back(Inst);
+ }
+ }
+ }
+}
+
/// isSCEVable - Test if values of the given type are analyzable within
/// the SCEV framework. This primarily includes integer types, and it
/// can optionally include pointer types if the ScalarEvolution class
@@ -1527,10 +1555,10 @@ bool ScalarEvolution::hasSCEV(Value *V) const {
SCEVHandle ScalarEvolution::getSCEV(Value *V) {
assert(isSCEVable(V->getType()) && "Value is not SCEVable!");
- std::map<SCEVCallbackVH, SCEVHandle>::iterator I = Scalars.find(V);
+ std::map<Value*, SCEVHandle>::iterator I = Scalars.find(V);
if (I != Scalars.end()) return I->second;
SCEVHandle S = createSCEV(V);
- Scalars.insert(std::make_pair(SCEVCallbackVH(V, this), S));
+ Scalars.insert(std::make_pair(V, S));
return S;
}
@@ -1619,8 +1647,7 @@ ScalarEvolution::getTruncateOrSignExtend(const SCEVHandle &V,
void ScalarEvolution::
ReplaceSymbolicValueWithConcrete(Instruction *I, const SCEVHandle &SymName,
const SCEVHandle &NewVal) {
- std::map<SCEVCallbackVH, SCEVHandle>::iterator SI =
- Scalars.find(SCEVCallbackVH(I, this));
+ std::map<Value*, SCEVHandle>::iterator SI = Scalars.find(I);
if (SI == Scalars.end()) return;
SCEVHandle NV =
@@ -1652,7 +1679,7 @@ SCEVHandle ScalarEvolution::createNodeForPHI(PHINode *PN) {
SCEVHandle SymbolicName = getUnknown(PN);
assert(Scalars.find(PN) == Scalars.end() &&
"PHI node already processed?");
- Scalars.insert(std::make_pair(SCEVCallbackVH(PN, this), SymbolicName));
+ Scalars.insert(std::make_pair(PN, SymbolicName));
// Using this symbolic name for the PHI, analyze the value coming around
// the back-edge.
@@ -2104,7 +2131,7 @@ void ScalarEvolution::forgetLoopBackedgeTakenCount(const Loop *L) {
void ScalarEvolution::forgetLoopPHIs(const Loop *L) {
for (BasicBlock::iterator I = L->getHeader()->begin();
PHINode *PN = dyn_cast<PHINode>(I); ++I)
- Scalars.erase(PN);
+ deleteValueFromRecords(PN);
}
/// ComputeBackedgeTakenCount - Compute the number of times the backedge
@@ -3317,25 +3344,6 @@ SCEVHandle SCEVAddRecExpr::getNumIterationsInRange(ConstantRange Range,
//===----------------------------------------------------------------------===//
-// SCEVCallbackVH Class Implementation
-//===----------------------------------------------------------------------===//
-
-void SCEVCallbackVH::deleted() {
- assert(SE && "SCEVCallbackVH called with a non-null ScalarEvolution!");
- SE->Scalars.erase(getValPtr());
- // this now dangles!
-}
-
-void SCEVCallbackVH::allUsesReplacedWith(Value *V) {
- assert(SE && "SCEVCallbackVH called with a non-null ScalarEvolution!");
- SE->Scalars.erase(getValPtr());
- // this now dangles!
-}
-
-SCEVCallbackVH::SCEVCallbackVH(Value *V, ScalarEvolution *se)
- : CallbackVH(V), SE(se) {}
-
-//===----------------------------------------------------------------------===//
// ScalarEvolution Class Implementation
//===----------------------------------------------------------------------===//
diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
index 3d9017d17e3..be94c457934 100644
--- a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -124,6 +124,7 @@ DeleteTriviallyDeadInstructions(SmallPtrSet<Instruction*, 16> &Insts) {
for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
if (Instruction *U = dyn_cast<Instruction>(I->getOperand(i)))
Insts.insert(U);
+ SE->deleteValueFromRecords(I);
DOUT << "INDVARS: Deleting: " << *I;
I->eraseFromParent();
Changed = true;
@@ -307,6 +308,7 @@ void IndVarSimplify::RewriteLoopExitValues(Loop *L,
// the PHI entirely. This is safe, because the NewVal won't be variant
// in the loop, so we don't need an LCSSA phi node anymore.
if (NumPreds == 1) {
+ SE->deleteValueFromRecords(PN);
PN->replaceAllUsesWith(ExitVal);
PN->eraseFromParent();
break;
diff --git a/llvm/lib/Transforms/Scalar/LoopDeletion.cpp b/llvm/lib/Transforms/Scalar/LoopDeletion.cpp
index 96b7a5288a7..83c25619bfc 100644
--- a/llvm/lib/Transforms/Scalar/LoopDeletion.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopDeletion.cpp
@@ -246,6 +246,13 @@ bool LoopDeletion::runOnLoop(Loop* L, LPPassManager& LPM) {
DT.eraseNode(*LI);
if (DF) DF->removeBlock(*LI);
+ // Remove instructions that we're deleting from ScalarEvolution.
+ for (BasicBlock::iterator BI = (*LI)->begin(), BE = (*LI)->end();
+ BI != BE; ++BI)
+ SE.deleteValueFromRecords(BI);
+
+ SE.deleteValueFromRecords(*LI);
+
// Remove the block from the reference counting scheme, so that we can
// delete it freely later.
(*LI)->dropAllReferences();
diff --git a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index 7d69dc83339..b9406651525 100644
--- a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -253,6 +253,8 @@ void LoopStrengthReduce::DeleteTriviallyDeadInstructions() {
if (I == 0 || !isInstructionTriviallyDead(I))
continue;
+ SE->deleteValueFromRecords(I);
+
for (User::op_iterator OI = I->op_begin(), E = I->op_end(); OI != E; ++OI) {
if (Instruction *U = dyn_cast<Instruction>(*OI)) {
*OI = 0;
@@ -2128,6 +2130,7 @@ ICmpInst *LoopStrengthReduce::ChangeCompareStride(Loop *L, ICmpInst *Cond,
// Remove the old compare instruction. The old indvar is probably dead too.
DeadInsts.push_back(cast<Instruction>(CondUse->OperandValToReplace));
+ SE->deleteValueFromRecords(OldCond);
OldCond->replaceAllUsesWith(Cond);
OldCond->eraseFromParent();
@@ -2248,12 +2251,16 @@ ICmpInst *LoopStrengthReduce::OptimizeSMax(Loop *L, ICmpInst *Cond,
Cond->getOperand(0), NewRHS, "scmp", Cond);
// Delete the max calculation instructions.
+ SE->deleteValueFromRecords(Cond);
Cond->replaceAllUsesWith(NewCond);
Cond->eraseFromParent();
Instruction *Cmp = cast<Instruction>(Sel->getOperand(0));
+ SE->deleteValueFromRecords(Sel);
Sel->eraseFromParent();
- if (Cmp->use_empty())
+ if (Cmp->use_empty()) {
+ SE->deleteValueFromRecords(Cmp);
Cmp->eraseFromParent();
+ }
CondUse->User = NewCond;
return NewCond;
}
@@ -2360,6 +2367,7 @@ void LoopStrengthReduce::OptimizeShadowIV(Loop *L) {
NewPH->addIncoming(NewIncr, PH->getIncomingBlock(Latch));
/* Remove cast operation */
+ SE->deleteValueFromRecords(ShadowUse);
ShadowUse->replaceAllUsesWith(NewPH);
ShadowUse->eraseFromParent();
SI->second.Users.erase(CandidateUI);
@@ -2499,8 +2507,17 @@ bool LoopStrengthReduce::runOnLoop(Loop *L, LPPassManager &LPM) {
DeleteTriviallyDeadInstructions();
// At this point, it is worth checking to see if any recurrence PHIs are also
- // dead, so that we can remove them as well.
- DeleteDeadPHIs(L->getHeader());
+ // dead, so that we can remove them as well. To keep ScalarEvolution
+ // current, use a ValueDeletionListener class.
+ struct LSRListener : public ValueDeletionListener {
+ ScalarEvolution &SE;
+ explicit LSRListener(ScalarEvolution &se) : SE(se) {}
+
+ virtual void ValueWillBeDeleted(Value *V) {
+ SE.deleteValueFromRecords(V);
+ }
+ } VDL(*SE);
+ DeleteDeadPHIs(L->getHeader(), &VDL);
return Changed;
}
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 93764b6d1a2..076f89e3374 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -78,8 +78,9 @@ void llvm::FoldSingleEntryPHINodes(BasicBlock *BB) {
/// DeleteDeadPHIs - Examine each PHI in the given block and delete it if it
/// is dead. Also recursively delete any operands that become dead as
/// a result. This includes tracing the def-use list from the PHI to see if
-/// it is ultimately unused or if it reaches an unused cycle.
-void llvm::DeleteDeadPHIs(BasicBlock *BB) {
+/// it is ultimately unused or if it reaches an unused cycle. If a
+/// ValueDeletionListener is specified, it is notified of the deletions.
+void llvm::DeleteDeadPHIs(BasicBlock *BB, ValueDeletionListener *VDL) {
// Recursively deleting a PHI may cause multiple PHIs to be deleted
// or RAUW'd undef, so use an array of WeakVH for the PHIs to delete.
SmallVector<WeakVH, 8> PHIs;
@@ -89,7 +90,7 @@ void llvm::DeleteDeadPHIs(BasicBlock *BB) {
for (unsigned i = 0, e = PHIs.size(); i != e; ++i)
if (PHINode *PN = dyn_cast_or_null<PHINode>(PHIs[i].operator Value*()))
- RecursivelyDeleteDeadPHINode(PN);
+ RecursivelyDeleteDeadPHINode(PN, VDL);
}
/// MergeBlockIntoPredecessor - Attempts to merge a block into its predecessor,
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index fea739cb46b..3b36362bb39 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -178,10 +178,18 @@ bool llvm::isInstructionTriviallyDead(Instruction *I) {
return false;
}
+/// ~ValueDeletionListener - A trivial dtor, defined out of line to give the
+/// class a home.
+llvm::ValueDeletionListener::~ValueDeletionListener() {}
+
/// RecursivelyDeleteTriviallyDeadInstructions - If the specified value is a
/// trivially dead instruction, delete it. If that makes any of its operands
/// trivially dead, delete them too, recursively.
-void llvm::RecursivelyDeleteTriviallyDeadInstructions(Value *V) {
+///
+/// If a ValueDeletionListener is specified, it is notified of instructions that
+/// are actually deleted (before they are actually deleted).
+void llvm::RecursivelyDeleteTriviallyDeadInstructions(Value *V,
+ ValueDeletionListener *VDL) {
Instruction *I = dyn_cast<Instruction>(V);
if (!I || !I->use_empty() || !isInstructionTriviallyDead(I))
return;
@@ -193,6 +201,10 @@ void llvm::RecursivelyDeleteTriviallyDeadInstructions(Value *V) {
I = DeadInsts.back();
DeadInsts.pop_back();
+ // If the client wanted to know, tell it about deleted instructions.
+ if (VDL)
+ VDL->ValueWillBeDeleted(I);
+
// Null out all of the instruction's operands to see if any operand becomes
// dead as we go.
for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
@@ -218,8 +230,11 @@ void llvm::RecursivelyDeleteTriviallyDeadInstructions(Value *V) {
/// either forms a cycle or is terminated by a trivially dead instruction,
/// delete it. If that makes any of its operands trivially dead, delete them
/// too, recursively.
+///
+/// If a ValueDeletionListener is specified, it is notified of instructions that
+/// are actually deleted (before they are actually deleted).
void
-llvm::RecursivelyDeleteDeadPHINode(PHINode *PN) {
+llvm::RecursivelyDeleteDeadPHINode(PHINode *PN, ValueDeletionListener *VDL) {
// We can remove a PHI if it is on a cycle in the def-use graph
// where each node in the cycle has degree one, i.e. only one use,
@@ -238,7 +253,7 @@ llvm::RecursivelyDeleteDeadPHINode(PHINode *PN) {
if (!PHIs.insert(cast<PHINode>(JP))) {
// Break the cycle and delete the PHI and its operands.
JP->replaceAllUsesWith(UndefValue::get(JP->getType()));
- RecursivelyDeleteTriviallyDeadInstructions(JP);
+ RecursivelyDeleteTriviallyDeadInstructions(JP, VDL);
break;
}
}
OpenPOWER on IntegriCloud