#include "llvm/GlobalVariable.h"
#include "llvm/Instructions.h"
#include "llvm/IntrinsicInst.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/Operator.h"
#include "llvm/Pass.h"
#include "llvm/Target/TargetData.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/Compiler.h"
+#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include <algorithm>
using namespace llvm;
// Useful predicates
//===----------------------------------------------------------------------===//
-static const User *isGEP(const Value *V) {
- if (isa<GetElementPtrInst>(V) ||
- (isa<ConstantExpr>(V) &&
- cast<ConstantExpr>(V)->getOpcode() == Instruction::GetElementPtr))
- return cast<User>(V);
- return 0;
+static const GEPOperator *isGEP(const Value *V) {
+ return dyn_cast<GEPOperator>(V);
}
static const Value *GetGEPOperands(const Value *V,
explicit NoAA(void *PID) : ImmutablePass(PID) { }
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
- AU.addRequired<TargetData>();
}
virtual void initializePass() {
- TD = &getAnalysis<TargetData>();
+ TD = getAnalysisIfAvailable<TargetData>();
}
virtual AliasResult alias(const Value *V1, unsigned V1Size,
virtual void getArgumentAccesses(Function *F, CallSite CS,
std::vector<PointerAccessInfo> &Info) {
- assert(0 && "This method may not be called on this function!");
+ llvm_unreachable("This method may not be called on this function!");
}
virtual void getMustAliases(Value *P, std::vector<Value*> &RetVals) { }
AliasAnalysis::AliasResult
BasicAliasAnalysis::alias(const Value *V1, unsigned V1Size,
const Value *V2, unsigned V2Size) {
- // Strip off any constant expression casts if they exist
- if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V1))
- if (CE->isCast() && isa<PointerType>(CE->getOperand(0)->getType()))
- V1 = CE->getOperand(0);
- if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V2))
- if (CE->isCast() && isa<PointerType>(CE->getOperand(0)->getType()))
- V2 = CE->getOperand(0);
+ // Strip off any casts if they exist.
+ V1 = V1->stripPointerCasts();
+ V2 = V2->stripPointerCasts();
// Are we checking for alias of the same value?
if (V1 == V2) return MustAlias;
if (!isa<PointerType>(V1->getType()) || !isa<PointerType>(V2->getType()))
return NoAlias; // Scalars cannot alias each other
- // Strip off cast instructions. Since V1 and V2 are pointers, they must be
- // pointer<->pointer bitcasts.
- if (const BitCastInst *I = dyn_cast<BitCastInst>(V1))
- return alias(I->getOperand(0), V1Size, V2, V2Size);
- if (const BitCastInst *I = dyn_cast<BitCastInst>(V2))
- return alias(V1, V1Size, I->getOperand(0), V2Size);
-
// Figure out what objects these things are pointing to if we can.
const Value *O1 = V1->getUnderlyingObject();
const Value *O2 = V2->getUnderlyingObject();
// 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.
- const TargetData &TD = getTargetData();
- if ((V1Size != ~0U && isObjectSmallerThan(O2, V1Size, TD)) ||
- (V2Size != ~0U && isObjectSmallerThan(O1, V2Size, TD)))
- return NoAlias;
+ if (TD)
+ if ((V1Size != ~0U && isObjectSmallerThan(O2, V1Size, *TD)) ||
+ (V2Size != ~0U && isObjectSmallerThan(O1, V2Size, *TD)))
+ return NoAlias;
// If one pointer is the result of a call/invoke and the other is a
// non-escaping local object, then we know the object couldn't escape to a
// the size of the argument... build an index vector that is equal to
// the arguments provided, except substitute 0's for any variable
// indexes we find...
- if (cast<PointerType>(
+ if (TD && cast<PointerType>(
BasePtr->getType())->getElementType()->isSized()) {
for (unsigned i = 0; i != GEPOperands.size(); ++i)
if (!isa<ConstantInt>(GEPOperands[i]))
GEPOperands[i] =
Constant::getNullValue(GEPOperands[i]->getType());
int64_t Offset =
- getTargetData().getIndexedOffset(BasePtr->getType(),
- &GEPOperands[0],
- GEPOperands.size());
+ TD->getIndexedOffset(BasePtr->getType(),
+ &GEPOperands[0],
+ GEPOperands.size());
if (Offset >= (int64_t)V2Size || Offset <= -(int64_t)V1Size)
return NoAlias;
// This function is used to determine if the indices of two GEP instructions are
// equal. V1 and V2 are the indices.
-static bool IndexOperandsEqual(Value *V1, Value *V2) {
+static bool IndexOperandsEqual(Value *V1, Value *V2, LLVMContext &Context) {
if (V1->getType() == V2->getType())
return V1 == V2;
if (Constant *C1 = dyn_cast<Constant>(V1))
if (Constant *C2 = dyn_cast<Constant>(V2)) {
// Sign extend the constants to long types, if necessary
- if (C1->getType() != Type::Int64Ty)
- C1 = ConstantExpr::getSExt(C1, Type::Int64Ty);
- if (C2->getType() != Type::Int64Ty)
- C2 = ConstantExpr::getSExt(C2, Type::Int64Ty);
+ if (C1->getType() != Type::getInt64Ty(Context))
+ C1 = ConstantExpr::getSExt(C1, Type::getInt64Ty(Context));
+ if (C2->getType() != Type::getInt64Ty(Context))
+ C2 = ConstantExpr::getSExt(C2, Type::getInt64Ty(Context));
return C1 == C2;
}
return false;
const PointerType *GEPPointerTy = cast<PointerType>(BasePtr1Ty);
+ LLVMContext &Context = GEPPointerTy->getContext();
+
// Find the (possibly empty) initial sequence of equal values... which are not
// necessarily constants.
unsigned NumGEP1Operands = NumGEP1Ops, NumGEP2Operands = NumGEP2Ops;
unsigned MaxOperands = std::max(NumGEP1Operands, NumGEP2Operands);
unsigned UnequalOper = 0;
while (UnequalOper != MinOperands &&
- IndexOperandsEqual(GEP1Ops[UnequalOper], GEP2Ops[UnequalOper])) {
+ IndexOperandsEqual(GEP1Ops[UnequalOper], GEP2Ops[UnequalOper],
+ Context)) {
// Advance through the type as we go...
++UnequalOper;
if (const CompositeType *CT = dyn_cast<CompositeType>(BasePtr1Ty))
if (Constant *G2OC = dyn_cast<ConstantInt>(const_cast<Value*>(G2Oper))){
if (G1OC->getType() != G2OC->getType()) {
// Sign extend both operands to long.
- if (G1OC->getType() != Type::Int64Ty)
- G1OC = ConstantExpr::getSExt(G1OC, Type::Int64Ty);
- if (G2OC->getType() != Type::Int64Ty)
- G2OC = ConstantExpr::getSExt(G2OC, Type::Int64Ty);
+ if (G1OC->getType() != Type::getInt64Ty(Context))
+ G1OC = ConstantExpr::getSExt(G1OC, Type::getInt64Ty(Context));
+ if (G2OC->getType() != Type::getInt64Ty(Context))
+ G2OC = ConstantExpr::getSExt(G2OC, Type::getInt64Ty(Context));
GEP1Ops[FirstConstantOper] = G1OC;
GEP2Ops[FirstConstantOper] = G2OC;
}
// However, one GEP may have more operands than the other. If this is the
// case, there may still be hope. Check this now.
if (FirstConstantOper == MinOperands) {
+ // Without TargetData, we won't know what the offsets are.
+ if (!TD)
+ return MayAlias;
+
// Make GEP1Ops be the longer one if there is a longer one.
if (NumGEP1Ops < NumGEP2Ops) {
std::swap(GEP1Ops, GEP2Ops);
GEP1Ops[i] = Constant::getNullValue(GEP1Ops[i]->getType());
// Okay, now get the offset. This is the relative offset for the full
// instruction.
- const TargetData &TD = getTargetData();
- int64_t Offset1 = TD.getIndexedOffset(GEPPointerTy, GEP1Ops,
- NumGEP1Ops);
+ int64_t Offset1 = TD->getIndexedOffset(GEPPointerTy, GEP1Ops,
+ NumGEP1Ops);
// Now check without any constants at the end.
- int64_t Offset2 = TD.getIndexedOffset(GEPPointerTy, GEP1Ops,
- MinOperands);
+ int64_t Offset2 = TD->getIndexedOffset(GEPPointerTy, GEP1Ops,
+ MinOperands);
// Make sure we compare the absolute difference.
if (Offset1 > Offset2)
const Type *ZeroIdxTy = GEPPointerTy;
for (unsigned i = 0; i != FirstConstantOper; ++i) {
if (!isa<StructType>(ZeroIdxTy))
- GEP1Ops[i] = GEP2Ops[i] = Constant::getNullValue(Type::Int32Ty);
+ GEP1Ops[i] = GEP2Ops[i] =
+ Constant::getNullValue(Type::getInt32Ty(Context));
if (const CompositeType *CT = dyn_cast<CompositeType>(ZeroIdxTy))
ZeroIdxTy = CT->getTypeAtIndex(GEP1Ops[i]);
// value possible.
//
if (const ArrayType *AT = dyn_cast<ArrayType>(BasePtr1Ty))
- GEP1Ops[i] = ConstantInt::get(Type::Int64Ty,AT->getNumElements()-1);
+ GEP1Ops[i] =
+ ConstantInt::get(Type::getInt64Ty(Context),
+ AT->getNumElements()-1);
else if (const VectorType *VT = dyn_cast<VectorType>(BasePtr1Ty))
- GEP1Ops[i] = ConstantInt::get(Type::Int64Ty,VT->getNumElements()-1);
+ GEP1Ops[i] =
+ ConstantInt::get(Type::getInt64Ty(Context),
+ VT->getNumElements()-1);
}
}
}
}
- if (GEPPointerTy->getElementType()->isSized()) {
+ if (TD && GEPPointerTy->getElementType()->isSized()) {
int64_t Offset1 =
- getTargetData().getIndexedOffset(GEPPointerTy, GEP1Ops, NumGEP1Ops);
+ TD->getIndexedOffset(GEPPointerTy, GEP1Ops, NumGEP1Ops);
int64_t Offset2 =
- getTargetData().getIndexedOffset(GEPPointerTy, GEP2Ops, NumGEP2Ops);
+ TD->getIndexedOffset(GEPPointerTy, GEP2Ops, NumGEP2Ops);
assert(Offset1 != Offset2 &&
"There is at least one different constant here!");