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-rw-r--r--include/llvm/Analysis/ScalarEvolution.h5
-rw-r--r--include/llvm/Analysis/ScalarEvolutionExpressions.h26
-rw-r--r--lib/Analysis/ScalarEvolution.cpp93
-rw-r--r--unittests/Analysis/Makefile15
-rw-r--r--unittests/Analysis/ScalarEvolutionTest.cpp82
-rw-r--r--unittests/Makefile2
6 files changed, 167 insertions, 56 deletions
diff --git a/include/llvm/Analysis/ScalarEvolution.h b/include/llvm/Analysis/ScalarEvolution.h
index 1b27efb..7f22420 100644
--- a/include/llvm/Analysis/ScalarEvolution.h
+++ b/include/llvm/Analysis/ScalarEvolution.h
@@ -661,6 +661,11 @@ namespace llvm {
private:
FoldingSet<SCEV> UniqueSCEVs;
BumpPtrAllocator SCEVAllocator;
+
+ /// FirstUnknown - The head of a linked list of all SCEVUnknown
+ /// values that have been allocated. This is used by releaseMemory
+ /// to locate them all and call their destructors.
+ SCEVUnknown *FirstUnknown;
};
}
diff --git a/include/llvm/Analysis/ScalarEvolutionExpressions.h b/include/llvm/Analysis/ScalarEvolutionExpressions.h
index ec4ac07..3e846e1 100644
--- a/include/llvm/Analysis/ScalarEvolutionExpressions.h
+++ b/include/llvm/Analysis/ScalarEvolutionExpressions.h
@@ -520,18 +520,28 @@ namespace llvm {
/// value, and only represent it as its LLVM Value. This is the "bottom"
/// value for the analysis.
///
- class SCEVUnknown : public SCEV {
+ class SCEVUnknown : public SCEV, private CallbackVH {
friend class ScalarEvolution;
- friend class ScalarEvolution::SCEVCallbackVH;
- // This should be an AssertingVH, however SCEVUnknowns are allocated in a
- // BumpPtrAllocator so their destructors are never called.
- Value *V;
- SCEVUnknown(const FoldingSetNodeIDRef ID, Value *v) :
- SCEV(ID, scUnknown), V(v) {}
+ // Implement CallbackVH.
+ virtual void deleted();
+ virtual void allUsesReplacedWith(Value *New);
+
+ /// SE - The parent ScalarEvolution value. This is used to update
+ /// the parent's maps when the value associated with a SCEVUnknown
+ /// is deleted or RAUW'd.
+ ScalarEvolution *SE;
+
+ /// Next - The next pointer in the linked list of all
+ /// SCEVUnknown instances owned by a ScalarEvolution.
+ SCEVUnknown *Next;
+
+ SCEVUnknown(const FoldingSetNodeIDRef ID, Value *V,
+ ScalarEvolution *se, SCEVUnknown *next) :
+ SCEV(ID, scUnknown), CallbackVH(V), SE(se), Next(next) {}
public:
- Value *getValue() const { return V; }
+ Value *getValue() const { return getValPtr(); }
/// isSizeOf, isAlignOf, isOffsetOf - Test whether this is a special
/// constant representing a type size, alignment, or field offset in
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index c6b7ad6..1dc8e83 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -337,12 +337,36 @@ void SCEVAddRecExpr::print(raw_ostream &OS) const {
OS << ">";
}
+void SCEVUnknown::deleted() {
+ // Clear this SCEVUnknown from ValuesAtScopes.
+ SE->ValuesAtScopes.erase(this);
+
+ // Remove this SCEVUnknown from the uniquing map.
+ SE->UniqueSCEVs.RemoveNode(this);
+
+ // Release the value.
+ setValPtr(0);
+}
+
+void SCEVUnknown::allUsesReplacedWith(Value *New) {
+ // Clear this SCEVUnknown from ValuesAtScopes.
+ SE->ValuesAtScopes.erase(this);
+
+ // Remove this SCEVUnknown from the uniquing map.
+ SE->UniqueSCEVs.RemoveNode(this);
+
+ // Update this SCEVUnknown to point to the new value. This is needed
+ // because there may still be outstanding SCEVs which still point to
+ // this SCEVUnknown.
+ setValPtr(New);
+}
+
bool SCEVUnknown::isLoopInvariant(const Loop *L) const {
// All non-instruction values are loop invariant. All instructions are loop
// invariant if they are not contained in the specified loop.
// Instructions are never considered invariant in the function body
// (null loop) because they are defined within the "loop".
- if (Instruction *I = dyn_cast<Instruction>(V))
+ if (Instruction *I = dyn_cast<Instruction>(getValue()))
return L && !L->contains(I);
return true;
}
@@ -360,11 +384,11 @@ bool SCEVUnknown::properlyDominates(BasicBlock *BB, DominatorTree *DT) const {
}
const Type *SCEVUnknown::getType() const {
- return V->getType();
+ return getValue()->getType();
}
bool SCEVUnknown::isSizeOf(const Type *&AllocTy) const {
- if (ConstantExpr *VCE = dyn_cast<ConstantExpr>(V))
+ if (ConstantExpr *VCE = dyn_cast<ConstantExpr>(getValue()))
if (VCE->getOpcode() == Instruction::PtrToInt)
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(VCE->getOperand(0)))
if (CE->getOpcode() == Instruction::GetElementPtr &&
@@ -381,7 +405,7 @@ bool SCEVUnknown::isSizeOf(const Type *&AllocTy) const {
}
bool SCEVUnknown::isAlignOf(const Type *&AllocTy) const {
- if (ConstantExpr *VCE = dyn_cast<ConstantExpr>(V))
+ if (ConstantExpr *VCE = dyn_cast<ConstantExpr>(getValue()))
if (VCE->getOpcode() == Instruction::PtrToInt)
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(VCE->getOperand(0)))
if (CE->getOpcode() == Instruction::GetElementPtr &&
@@ -406,7 +430,7 @@ bool SCEVUnknown::isAlignOf(const Type *&AllocTy) const {
}
bool SCEVUnknown::isOffsetOf(const Type *&CTy, Constant *&FieldNo) const {
- if (ConstantExpr *VCE = dyn_cast<ConstantExpr>(V))
+ if (ConstantExpr *VCE = dyn_cast<ConstantExpr>(getValue()))
if (VCE->getOpcode() == Instruction::PtrToInt)
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(VCE->getOperand(0)))
if (CE->getOpcode() == Instruction::GetElementPtr &&
@@ -448,7 +472,7 @@ void SCEVUnknown::print(raw_ostream &OS) const {
}
// Otherwise just print it normally.
- WriteAsOperand(OS, V, false);
+ WriteAsOperand(OS, getValue(), false);
}
//===----------------------------------------------------------------------===//
@@ -2350,8 +2374,14 @@ const SCEV *ScalarEvolution::getUnknown(Value *V) {
ID.AddInteger(scUnknown);
ID.AddPointer(V);
void *IP = 0;
- if (const SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) return S;
- SCEV *S = new (SCEVAllocator) SCEVUnknown(ID.Intern(SCEVAllocator), V);
+ if (SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) {
+ assert(cast<SCEVUnknown>(S)->getValue() == V &&
+ "Stale SCEVUnknown in uniquing map!");
+ return S;
+ }
+ SCEV *S = new (SCEVAllocator) SCEVUnknown(ID.Intern(SCEVAllocator), V, this,
+ FirstUnknown);
+ FirstUnknown = cast<SCEVUnknown>(S);
UniqueSCEVs.InsertNode(S, IP);
return S;
}
@@ -3664,26 +3694,6 @@ void ScalarEvolution::forgetLoop(const Loop *L) {
/// changed a value in a way that may effect its value, or which may
/// disconnect it from a def-use chain linking it to a loop.
void ScalarEvolution::forgetValue(Value *V) {
- // If there's a SCEVUnknown tying this value into the SCEV
- // space, remove it from the folding set map. The SCEVUnknown
- // object and any other SCEV objects which reference it
- // (transitively) remain allocated, effectively leaked until
- // the underlying BumpPtrAllocator is freed.
- //
- // This permits SCEV pointers to be used as keys in maps
- // such as the ValuesAtScopes map.
- FoldingSetNodeID ID;
- ID.AddInteger(scUnknown);
- ID.AddPointer(V);
- void *IP;
- if (SCEV *S = UniqueSCEVs.FindNodeOrInsertPos(ID, IP)) {
- UniqueSCEVs.RemoveNode(S);
-
- // This isn't necessary, but we might as well remove the
- // value from the ValuesAtScopes map too.
- ValuesAtScopes.erase(S);
- }
-
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return;
@@ -5693,27 +5703,10 @@ void ScalarEvolution::SCEVCallbackVH::deleted() {
void ScalarEvolution::SCEVCallbackVH::allUsesReplacedWith(Value *V) {
assert(SE && "SCEVCallbackVH called with a null ScalarEvolution!");
- Value *Old = getValPtr();
-
- // If there's a SCEVUnknown tying this value into the SCEV
- // space, replace the SCEVUnknown's value with the new value
- // for the benefit of any SCEVs still referencing it, and
- // and remove it from the folding set map so that new scevs
- // don't reference it.
- FoldingSetNodeID ID;
- ID.AddInteger(scUnknown);
- ID.AddPointer(Old);
- void *IP;
- if (SCEVUnknown *S = cast_or_null<SCEVUnknown>(
- SE->UniqueSCEVs.FindNodeOrInsertPos(ID, IP))) {
- S->V = V;
- SE->UniqueSCEVs.RemoveNode(S);
- SE->ValuesAtScopes.erase(S);
- }
-
// Forget all the expressions associated with users of the old value,
// so that future queries will recompute the expressions using the new
// value.
+ Value *Old = getValPtr();
SmallVector<User *, 16> Worklist;
SmallPtrSet<User *, 8> Visited;
for (Value::use_iterator UI = Old->use_begin(), UE = Old->use_end();
@@ -5749,7 +5742,7 @@ ScalarEvolution::SCEVCallbackVH::SCEVCallbackVH(Value *V, ScalarEvolution *se)
//===----------------------------------------------------------------------===//
ScalarEvolution::ScalarEvolution()
- : FunctionPass(&ID) {
+ : FunctionPass(&ID), FirstUnknown(0) {
}
bool ScalarEvolution::runOnFunction(Function &F) {
@@ -5761,6 +5754,12 @@ bool ScalarEvolution::runOnFunction(Function &F) {
}
void ScalarEvolution::releaseMemory() {
+ // Iterate through all the SCEVUnknown instances and call their
+ // destructors, so that they release their references to their values.
+ for (SCEVUnknown *U = FirstUnknown; U; U = U->Next)
+ U->~SCEVUnknown();
+ FirstUnknown = 0;
+
Scalars.clear();
BackedgeTakenCounts.clear();
ConstantEvolutionLoopExitValue.clear();
diff --git a/unittests/Analysis/Makefile b/unittests/Analysis/Makefile
new file mode 100644
index 0000000..f89240e
--- /dev/null
+++ b/unittests/Analysis/Makefile
@@ -0,0 +1,15 @@
+##===- unittests/Analysis/Makefile -------------------------*- Makefile -*-===##
+#
+# The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+##===----------------------------------------------------------------------===##
+
+LEVEL = ../..
+TESTNAME = Analysis
+LINK_COMPONENTS := core support target analysis ipa
+
+include $(LEVEL)/Makefile.config
+include $(LLVM_SRC_ROOT)/unittests/Makefile.unittest
diff --git a/unittests/Analysis/ScalarEvolutionTest.cpp b/unittests/Analysis/ScalarEvolutionTest.cpp
new file mode 100644
index 0000000..b734160
--- /dev/null
+++ b/unittests/Analysis/ScalarEvolutionTest.cpp
@@ -0,0 +1,82 @@
+//===- ScalarEvolutionsTest.cpp - ScalarEvolution unit tests --------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <llvm/Analysis/ScalarEvolutionExpressions.h>
+#include <llvm/GlobalVariable.h>
+#include <llvm/Constants.h>
+#include <llvm/LLVMContext.h>
+#include <llvm/Module.h>
+#include <llvm/PassManager.h>
+#include "gtest/gtest.h"
+
+namespace llvm {
+namespace {
+
+TEST(ScalarEvolutionsTest, SCEVUnknownRAUW) {
+ LLVMContext Context;
+ Module M("world", Context);
+
+ const FunctionType *FTy = FunctionType::get(Type::getVoidTy(Context),
+ std::vector<const Type *>(), false);
+ Function *F = cast<Function>(M.getOrInsertFunction("f", FTy));
+ BasicBlock *BB = BasicBlock::Create(Context, "entry", F);
+ ReturnInst::Create(Context, 0, BB);
+
+ const Type *Ty = Type::getInt1Ty(Context);
+ Constant *Init = Constant::getNullValue(Ty);
+ Value *V0 = new GlobalVariable(M, Ty, false, GlobalValue::ExternalLinkage, Init, "V0");
+ Value *V1 = new GlobalVariable(M, Ty, false, GlobalValue::ExternalLinkage, Init, "V1");
+ Value *V2 = new GlobalVariable(M, Ty, false, GlobalValue::ExternalLinkage, Init, "V2");
+
+ // Create a ScalarEvolution and "run" it so that it gets initialized.
+ PassManager PM;
+ ScalarEvolution &SE = *new ScalarEvolution();
+ PM.add(&SE);
+ PM.run(M);
+
+ const SCEV *S0 = SE.getSCEV(V0);
+ const SCEV *S1 = SE.getSCEV(V1);
+ const SCEV *S2 = SE.getSCEV(V2);
+
+ const SCEV *P0 = SE.getAddExpr(S0, S0);
+ const SCEV *P1 = SE.getAddExpr(S1, S1);
+ const SCEV *P2 = SE.getAddExpr(S2, S2);
+
+ const SCEVMulExpr *M0 = cast<SCEVMulExpr>(P0);
+ const SCEVMulExpr *M1 = cast<SCEVMulExpr>(P1);
+ const SCEVMulExpr *M2 = cast<SCEVMulExpr>(P2);
+
+ EXPECT_EQ(cast<SCEVConstant>(M0->getOperand(0))->getValue()->getZExtValue(),
+ 2u);
+ EXPECT_EQ(cast<SCEVConstant>(M1->getOperand(0))->getValue()->getZExtValue(),
+ 2u);
+ EXPECT_EQ(cast<SCEVConstant>(M2->getOperand(0))->getValue()->getZExtValue(),
+ 2u);
+
+ // Before the RAUWs, these are all pointing to separate values.
+ EXPECT_EQ(cast<SCEVUnknown>(M0->getOperand(1))->getValue(), V0);
+ EXPECT_EQ(cast<SCEVUnknown>(M1->getOperand(1))->getValue(), V1);
+ EXPECT_EQ(cast<SCEVUnknown>(M2->getOperand(1))->getValue(), V2);
+
+ // Do some RAUWs.
+ V2->replaceAllUsesWith(V1);
+ V1->replaceAllUsesWith(V0);
+
+ // After the RAUWs, these should all be pointing to V0.
+ EXPECT_EQ(cast<SCEVUnknown>(M0->getOperand(1))->getValue(), V0);
+ EXPECT_EQ(cast<SCEVUnknown>(M1->getOperand(1))->getValue(), V0);
+ EXPECT_EQ(cast<SCEVUnknown>(M2->getOperand(1))->getValue(), V0);
+
+ // Manually clean up, since we allocated new SCEV objects after the
+ // pass was finished.
+ SE.releaseMemory();
+}
+
+} // end anonymous namespace
+} // end namespace llvm
diff --git a/unittests/Makefile b/unittests/Makefile
index 9f377cd..0401cd1 100644
--- a/unittests/Makefile
+++ b/unittests/Makefile
@@ -9,7 +9,7 @@
LEVEL = ..
-PARALLEL_DIRS = ADT ExecutionEngine Support Transforms VMCore
+PARALLEL_DIRS = ADT ExecutionEngine Support Transforms VMCore Analysis
include $(LEVEL)/Makefile.common
generated by cgit v1.1 at 2024-06-28 15:19:29 +0000