Enhance analysis passes so that they apply the same analysis to malloc calls as to MallocInst.
Reviewed by Eli Friedman.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82281 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index 9e9d0f1..5fa87ff 100644
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -15,6 +15,7 @@
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/CaptureTracking.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/Analysis/Passes.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
@@ -102,7 +103,7 @@
/// isObjectSmallerThan - Return true if we can prove that the object specified
/// by V is smaller than Size.
static bool isObjectSmallerThan(const Value *V, unsigned Size,
- const TargetData &TD) {
+ LLVMContext &Context, const TargetData &TD) {
const Type *AccessTy;
if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
AccessTy = GV->getType()->getElementType();
@@ -111,6 +112,12 @@
AccessTy = AI->getType()->getElementType();
else
return false;
+ } else if (const CallInst* CI = extractMallocCall(V)) {
+ if (!isArrayMalloc(V, Context, &TD))
+ // The size is the argument to the malloc call.
+ if (const ConstantInt* C = dyn_cast<ConstantInt>(CI->getOperand(1)))
+ return (C->getZExtValue() < Size);
+ return false;
} else if (const Argument *A = dyn_cast<Argument>(V)) {
if (A->hasByValAttr())
AccessTy = cast<PointerType>(A->getType())->getElementType();
@@ -340,9 +347,10 @@
// If the size of one access is larger than the entire object on the other
// side, then we know such behavior is undefined and can assume no alias.
+ LLVMContext &Context = V1->getContext();
if (TD)
- if ((V1Size != ~0U && isObjectSmallerThan(O2, V1Size, *TD)) ||
- (V2Size != ~0U && isObjectSmallerThan(O1, V2Size, *TD)))
+ if ((V1Size != ~0U && isObjectSmallerThan(O2, V1Size, Context, *TD)) ||
+ (V2Size != ~0U && isObjectSmallerThan(O1, V2Size, Context, *TD)))
return NoAlias;
// If one pointer is the result of a call/invoke and the other is a
diff --git a/lib/Analysis/IPA/Andersens.cpp b/lib/Analysis/IPA/Andersens.cpp
index 9de1fcc..1c9159d 100644
--- a/lib/Analysis/IPA/Andersens.cpp
+++ b/lib/Analysis/IPA/Andersens.cpp
@@ -64,6 +64,7 @@
#include "llvm/Support/InstIterator.h"
#include "llvm/Support/InstVisitor.h"
#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/Analysis/Passes.h"
#include "llvm/Support/Debug.h"
#include "llvm/System/Atomic.h"
@@ -592,9 +593,12 @@
friend class InstVisitor<Andersens>;
void visitReturnInst(ReturnInst &RI);
void visitInvokeInst(InvokeInst &II) { visitCallSite(CallSite(&II)); }
- void visitCallInst(CallInst &CI) { visitCallSite(CallSite(&CI)); }
+ void visitCallInst(CallInst &CI) {
+ if (isMalloc(&CI)) visitAllocationInst(CI);
+ else visitCallSite(CallSite(&CI));
+ }
void visitCallSite(CallSite CS);
- void visitAllocationInst(AllocationInst &AI);
+ void visitAllocationInst(Instruction &I);
void visitLoadInst(LoadInst &LI);
void visitStoreInst(StoreInst &SI);
void visitGetElementPtrInst(GetElementPtrInst &GEP);
@@ -790,6 +794,8 @@
ValueNodes[&*II] = NumObjects++;
if (AllocationInst *AI = dyn_cast<AllocationInst>(&*II))
ObjectNodes[AI] = NumObjects++;
+ else if (isMalloc(&*II))
+ ObjectNodes[&*II] = NumObjects++;
}
// Calls to inline asm need to be added as well because the callee isn't
@@ -1161,10 +1167,10 @@
}
}
-void Andersens::visitAllocationInst(AllocationInst &AI) {
- unsigned ObjectIndex = getObject(&AI);
- GraphNodes[ObjectIndex].setValue(&AI);
- Constraints.push_back(Constraint(Constraint::AddressOf, getNodeValue(AI),
+void Andersens::visitAllocationInst(Instruction &I) {
+ unsigned ObjectIndex = getObject(&I);
+ GraphNodes[ObjectIndex].setValue(&I);
+ Constraints.push_back(Constraint(Constraint::AddressOf, getNodeValue(I),
ObjectIndex));
}
@@ -2813,7 +2819,7 @@
else
errs() << "(unnamed)";
- if (isa<GlobalValue>(V) || isa<AllocationInst>(V))
+ if (isa<GlobalValue>(V) || isa<AllocationInst>(V) || isMalloc(V))
if (N == &GraphNodes[getObject(V)])
errs() << "<mem>";
}
diff --git a/lib/Analysis/IPA/GlobalsModRef.cpp b/lib/Analysis/IPA/GlobalsModRef.cpp
index 2e9884a..f5c1108 100644
--- a/lib/Analysis/IPA/GlobalsModRef.cpp
+++ b/lib/Analysis/IPA/GlobalsModRef.cpp
@@ -23,6 +23,7 @@
#include "llvm/DerivedTypes.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/CallGraph.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/InstIterator.h"
@@ -236,6 +237,9 @@
}
} else if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(*UI)) {
if (AnalyzeUsesOfPointer(GEP, Readers, Writers)) return true;
+ } else if (BitCastInst *BCI = dyn_cast<BitCastInst>(*UI)) {
+ if (AnalyzeUsesOfPointer(BCI, Readers, Writers, OkayStoreDest))
+ return true;
} else if (CallInst *CI = dyn_cast<CallInst>(*UI)) {
// Make sure that this is just the function being called, not that it is
// passing into the function.
@@ -299,7 +303,7 @@
// Check the value being stored.
Value *Ptr = SI->getOperand(0)->getUnderlyingObject();
- if (isa<MallocInst>(Ptr)) {
+ if (isa<MallocInst>(Ptr) || isMalloc(Ptr)) {
// Okay, easy case.
} else if (CallInst *CI = dyn_cast<CallInst>(Ptr)) {
Function *F = CI->getCalledFunction();
@@ -435,7 +439,8 @@
if (cast<StoreInst>(*II).isVolatile())
// Treat volatile stores as reading memory somewhere.
FunctionEffect |= Ref;
- } else if (isa<MallocInst>(*II) || isa<FreeInst>(*II)) {
+ } else if (isa<MallocInst>(*II) || isa<FreeInst>(*II) ||
+ isMalloc(&cast<Instruction>(*II))) {
FunctionEffect |= ModRef;
}
diff --git a/lib/Analysis/MemoryDependenceAnalysis.cpp b/lib/Analysis/MemoryDependenceAnalysis.cpp
index 2ac101e..97b791c 100644
--- a/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -20,6 +20,7 @@
#include "llvm/IntrinsicInst.h"
#include "llvm/Function.h"
#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/PredIteratorCache.h"
@@ -233,6 +234,15 @@
continue;
}
+ if (isMalloc(Inst)) {
+ Value *AccessPtr = MemPtr->getUnderlyingObject();
+
+ if (AccessPtr == Inst ||
+ AA->alias(Inst, 1, AccessPtr, 1) == AliasAnalysis::MustAlias)
+ return MemDepResult::getDef(Inst);
+ continue;
+ }
+
// See if this instruction (e.g. a call or vaarg) mod/ref's the pointer.
switch (AA->getModRefInfo(Inst, MemPtr, MemSize)) {
case AliasAnalysis::NoModRef:
diff --git a/lib/Analysis/PointerTracking.cpp b/lib/Analysis/PointerTracking.cpp
index e098647..2281836 100644
--- a/lib/Analysis/PointerTracking.cpp
+++ b/lib/Analysis/PointerTracking.cpp
@@ -13,6 +13,7 @@
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/Analysis/MallocHelper.h"
#include "llvm/Analysis/PointerTracking.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
@@ -99,6 +100,14 @@
return SE->getSCEV(arraySize);
}
+ if (CallInst *CI = extractMallocCall(V)) {
+ Value *arraySize = getMallocArraySize(CI, P->getContext(), TD);
+ Ty = getMallocAllocatedType(CI);
+ if (!Ty || !arraySize) return SE->getCouldNotCompute();
+ // arraySize elements of type Ty.
+ return SE->getSCEV(arraySize);
+ }
+
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
if (GV->hasDefinitiveInitializer()) {
Constant *C = GV->getInitializer();