[llvm-commits] [llvm] r170991 - /llvm/trunk/lib/Analysis/ValueTracking.cpp
Craig Topper
craig.topper at gmail.com
Sat Dec 22 11:15:35 PST 2012
Author: ctopper
Date: Sat Dec 22 13:15:35 2012
New Revision: 170991
URL: http://llvm.org/viewvc/llvm-project?rev=170991&view=rev
Log:
Remove trailing whitespace.
Modified:
llvm/trunk/lib/Analysis/ValueTracking.cpp
Modified: llvm/trunk/lib/Analysis/ValueTracking.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ValueTracking.cpp?rev=170991&r1=170990&r2=170991&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/ValueTracking.cpp (original)
+++ llvm/trunk/lib/Analysis/ValueTracking.cpp Sat Dec 22 13:15:35 2012
@@ -58,7 +58,7 @@
// NLZ can't be BitWidth with no sign bit
APInt MaskV = APInt::getHighBitsSet(BitWidth, NLZ+1);
llvm::ComputeMaskedBits(Op1, KnownZero2, KnownOne2, TD, Depth+1);
-
+
// If all of the MaskV bits are known to be zero, then we know the
// output top bits are zero, because we now know that the output is
// from [0-C].
@@ -84,7 +84,7 @@
unsigned LHSKnownZeroOut = LHSKnownZero.countTrailingOnes();
llvm::ComputeMaskedBits(Op1, KnownZero2, KnownOne2, TD, Depth+1);
- assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
unsigned RHSKnownZeroOut = KnownZero2.countTrailingOnes();
// Determine which operand has more trailing zeros, and use that
@@ -266,11 +266,11 @@
for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
Elt = CDS->getElementAsInteger(i);
KnownZero &= ~Elt;
- KnownOne &= Elt;
+ KnownOne &= Elt;
}
return;
}
-
+
// The address of an aligned GlobalValue has trailing zeros.
if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
unsigned Align = GV->getAlignment();
@@ -306,7 +306,7 @@
}
return;
}
-
+
if (Argument *A = dyn_cast<Argument>(V)) {
unsigned Align = 0;
@@ -345,9 +345,9 @@
// If either the LHS or the RHS are Zero, the result is zero.
ComputeMaskedBits(I->getOperand(1), KnownZero, KnownOne, TD, Depth+1);
ComputeMaskedBits(I->getOperand(0), KnownZero2, KnownOne2, TD, Depth+1);
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
- assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
-
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
+
// Output known-1 bits are only known if set in both the LHS & RHS.
KnownOne &= KnownOne2;
// Output known-0 are known to be clear if zero in either the LHS | RHS.
@@ -357,9 +357,9 @@
case Instruction::Or: {
ComputeMaskedBits(I->getOperand(1), KnownZero, KnownOne, TD, Depth+1);
ComputeMaskedBits(I->getOperand(0), KnownZero2, KnownOne2, TD, Depth+1);
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
- assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
-
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
+
// Output known-0 bits are only known if clear in both the LHS & RHS.
KnownZero &= KnownZero2;
// Output known-1 are known to be set if set in either the LHS | RHS.
@@ -369,9 +369,9 @@
case Instruction::Xor: {
ComputeMaskedBits(I->getOperand(1), KnownZero, KnownOne, TD, Depth+1);
ComputeMaskedBits(I->getOperand(0), KnownZero2, KnownOne2, TD, Depth+1);
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
- assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
-
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
+
// Output known-0 bits are known if clear or set in both the LHS & RHS.
APInt KnownZeroOut = (KnownZero & KnownZero2) | (KnownOne & KnownOne2);
// Output known-1 are known to be set if set in only one of the LHS, RHS.
@@ -407,8 +407,8 @@
ComputeMaskedBits(I->getOperand(2), KnownZero, KnownOne, TD, Depth+1);
ComputeMaskedBits(I->getOperand(1), KnownZero2, KnownOne2, TD,
Depth+1);
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
- assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
// Only known if known in both the LHS and RHS.
KnownOne &= KnownOne2;
@@ -465,11 +465,11 @@
case Instruction::SExt: {
// Compute the bits in the result that are not present in the input.
unsigned SrcBitWidth = I->getOperand(0)->getType()->getScalarSizeInBits();
-
+
KnownZero = KnownZero.trunc(SrcBitWidth);
KnownOne = KnownOne.trunc(SrcBitWidth);
ComputeMaskedBits(I->getOperand(0), KnownZero, KnownOne, TD, Depth+1);
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
KnownZero = KnownZero.zext(BitWidth);
KnownOne = KnownOne.zext(BitWidth);
@@ -486,7 +486,7 @@
if (ConstantInt *SA = dyn_cast<ConstantInt>(I->getOperand(1))) {
uint64_t ShiftAmt = SA->getLimitedValue(BitWidth);
ComputeMaskedBits(I->getOperand(0), KnownZero, KnownOne, TD, Depth+1);
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
KnownZero <<= ShiftAmt;
KnownOne <<= ShiftAmt;
KnownZero |= APInt::getLowBitsSet(BitWidth, ShiftAmt); // low bits known 0
@@ -498,10 +498,10 @@
if (ConstantInt *SA = dyn_cast<ConstantInt>(I->getOperand(1))) {
// Compute the new bits that are at the top now.
uint64_t ShiftAmt = SA->getLimitedValue(BitWidth);
-
+
// Unsigned shift right.
ComputeMaskedBits(I->getOperand(0), KnownZero,KnownOne, TD, Depth+1);
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
KnownZero = APIntOps::lshr(KnownZero, ShiftAmt);
KnownOne = APIntOps::lshr(KnownOne, ShiftAmt);
// high bits known zero.
@@ -514,13 +514,13 @@
if (ConstantInt *SA = dyn_cast<ConstantInt>(I->getOperand(1))) {
// Compute the new bits that are at the top now.
uint64_t ShiftAmt = SA->getLimitedValue(BitWidth-1);
-
+
// Signed shift right.
ComputeMaskedBits(I->getOperand(0), KnownZero, KnownOne, TD, Depth+1);
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
KnownZero = APIntOps::lshr(KnownZero, ShiftAmt);
KnownOne = APIntOps::lshr(KnownOne, ShiftAmt);
-
+
APInt HighBits(APInt::getHighBitsSet(BitWidth, ShiftAmt));
if (KnownZero[BitWidth-ShiftAmt-1]) // New bits are known zero.
KnownZero |= HighBits;
@@ -564,7 +564,7 @@
if (KnownOne2[BitWidth-1] && ((KnownOne2 & LowBits) != 0))
KnownOne |= ~LowBits;
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
}
}
@@ -611,7 +611,7 @@
unsigned Align = AI->getAlignment();
if (Align == 0 && TD)
Align = TD->getABITypeAlignment(AI->getType()->getElementType());
-
+
if (Align > 0)
KnownZero = APInt::getLowBitsSet(BitWidth, CountTrailingZeros_32(Align));
break;
@@ -648,7 +648,7 @@
LocalKnownZero.countTrailingOnes()));
}
}
-
+
KnownZero = APInt::getLowBitsSet(BitWidth, TrailZ);
break;
}
@@ -1073,7 +1073,7 @@
const DataLayout *TD, unsigned Depth) {
APInt KnownZero(Mask.getBitWidth(), 0), KnownOne(Mask.getBitWidth(), 0);
ComputeMaskedBits(V, KnownZero, KnownOne, TD, Depth);
- assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
+ assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
return (KnownZero & Mask) == Mask;
}
@@ -1103,14 +1103,14 @@
if (Depth == 6)
return 1; // Limit search depth.
-
+
Operator *U = dyn_cast<Operator>(V);
switch (Operator::getOpcode(V)) {
default: break;
case Instruction::SExt:
Tmp = TyBits - U->getOperand(0)->getType()->getScalarSizeInBits();
return ComputeNumSignBits(U->getOperand(0), TD, Depth+1) + Tmp;
-
+
case Instruction::AShr: {
Tmp = ComputeNumSignBits(U->getOperand(0), TD, Depth+1);
// ashr X, C -> adds C sign bits. Vectors too.
@@ -1152,38 +1152,38 @@
if (Tmp == 1) return 1; // Early out.
Tmp2 = ComputeNumSignBits(U->getOperand(2), TD, Depth+1);
return std::min(Tmp, Tmp2);
-
+
case Instruction::Add:
// Add can have at most one carry bit. Thus we know that the output
// is, at worst, one more bit than the inputs.
Tmp = ComputeNumSignBits(U->getOperand(0), TD, Depth+1);
if (Tmp == 1) return 1; // Early out.
-
+
// Special case decrementing a value (ADD X, -1):
if (ConstantInt *CRHS = dyn_cast<ConstantInt>(U->getOperand(1)))
if (CRHS->isAllOnesValue()) {
APInt KnownZero(TyBits, 0), KnownOne(TyBits, 0);
ComputeMaskedBits(U->getOperand(0), KnownZero, KnownOne, TD, Depth+1);
-
+
// If the input is known to be 0 or 1, the output is 0/-1, which is all
// sign bits set.
if ((KnownZero | APInt(TyBits, 1)).isAllOnesValue())
return TyBits;
-
+
// If we are subtracting one from a positive number, there is no carry
// out of the result.
if (KnownZero.isNegative())
return Tmp;
}
-
+
Tmp2 = ComputeNumSignBits(U->getOperand(1), TD, Depth+1);
if (Tmp2 == 1) return 1;
return std::min(Tmp, Tmp2)-1;
-
+
case Instruction::Sub:
Tmp2 = ComputeNumSignBits(U->getOperand(1), TD, Depth+1);
if (Tmp2 == 1) return 1;
-
+
// Handle NEG.
if (ConstantInt *CLHS = dyn_cast<ConstantInt>(U->getOperand(0)))
if (CLHS->isNullValue()) {
@@ -1193,26 +1193,26 @@
// sign bits set.
if ((KnownZero | APInt(TyBits, 1)).isAllOnesValue())
return TyBits;
-
+
// If the input is known to be positive (the sign bit is known clear),
// the output of the NEG has the same number of sign bits as the input.
if (KnownZero.isNegative())
return Tmp2;
-
+
// Otherwise, we treat this like a SUB.
}
-
+
// Sub can have at most one carry bit. Thus we know that the output
// is, at worst, one more bit than the inputs.
Tmp = ComputeNumSignBits(U->getOperand(0), TD, Depth+1);
if (Tmp == 1) return 1; // Early out.
return std::min(Tmp, Tmp2)-1;
-
+
case Instruction::PHI: {
PHINode *PN = cast<PHINode>(U);
// Don't analyze large in-degree PHIs.
if (PN->getNumIncomingValues() > 4) break;
-
+
// Take the minimum of all incoming values. This can't infinitely loop
// because of our depth threshold.
Tmp = ComputeNumSignBits(PN->getIncomingValue(0), TD, Depth+1);
@@ -1229,13 +1229,13 @@
// case for targets like X86.
break;
}
-
+
// Finally, if we can prove that the top bits of the result are 0's or 1's,
// use this information.
APInt KnownZero(TyBits, 0), KnownOne(TyBits, 0);
APInt Mask;
ComputeMaskedBits(V, KnownZero, KnownOne, TD, Depth);
-
+
if (KnownZero.isNegative()) { // sign bit is 0
Mask = KnownZero;
} else if (KnownOne.isNegative()) { // sign bit is 1;
@@ -1244,7 +1244,7 @@
// Nothing known.
return FirstAnswer;
}
-
+
// Okay, we know that the sign bit in Mask is set. Use CLZ to determine
// the number of identical bits in the top of the input value.
Mask = ~Mask;
@@ -1272,7 +1272,7 @@
if (Base == 0)
return false;
-
+
if (Base == 1) {
Multiple = V;
return true;
@@ -1288,11 +1288,11 @@
if (CI && CI->getZExtValue() % Base == 0) {
Multiple = ConstantInt::get(T, CI->getZExtValue() / Base);
- return true;
+ return true;
}
-
+
if (Depth == MaxDepth) return false; // Limit search depth.
-
+
Operator *I = dyn_cast<Operator>(V);
if (!I) return false;
@@ -1324,13 +1324,13 @@
if (ComputeMultiple(Op0, Base, Mul0, LookThroughSExt, Depth+1)) {
if (Constant *Op1C = dyn_cast<Constant>(Op1))
if (Constant *MulC = dyn_cast<Constant>(Mul0)) {
- if (Op1C->getType()->getPrimitiveSizeInBits() <
+ if (Op1C->getType()->getPrimitiveSizeInBits() <
MulC->getType()->getPrimitiveSizeInBits())
Op1C = ConstantExpr::getZExt(Op1C, MulC->getType());
- if (Op1C->getType()->getPrimitiveSizeInBits() >
+ if (Op1C->getType()->getPrimitiveSizeInBits() >
MulC->getType()->getPrimitiveSizeInBits())
MulC = ConstantExpr::getZExt(MulC, Op1C->getType());
-
+
// V == Base * (Mul0 * Op1), so return (Mul0 * Op1)
Multiple = ConstantExpr::getMul(MulC, Op1C);
return true;
@@ -1348,13 +1348,13 @@
if (ComputeMultiple(Op1, Base, Mul1, LookThroughSExt, Depth+1)) {
if (Constant *Op0C = dyn_cast<Constant>(Op0))
if (Constant *MulC = dyn_cast<Constant>(Mul1)) {
- if (Op0C->getType()->getPrimitiveSizeInBits() <
+ if (Op0C->getType()->getPrimitiveSizeInBits() <
MulC->getType()->getPrimitiveSizeInBits())
Op0C = ConstantExpr::getZExt(Op0C, MulC->getType());
- if (Op0C->getType()->getPrimitiveSizeInBits() >
+ if (Op0C->getType()->getPrimitiveSizeInBits() >
MulC->getType()->getPrimitiveSizeInBits())
MulC = ConstantExpr::getZExt(MulC, Op0C->getType());
-
+
// V == Base * (Mul1 * Op0), so return (Mul1 * Op0)
Multiple = ConstantExpr::getMul(MulC, Op0C);
return true;
@@ -1374,7 +1374,7 @@
return false;
}
-/// CannotBeNegativeZero - Return true if we can prove that the specified FP
+/// CannotBeNegativeZero - Return true if we can prove that the specified FP
/// value is never equal to -0.0.
///
/// NOTE: this function will need to be revisited when we support non-default
@@ -1383,7 +1383,7 @@
bool llvm::CannotBeNegativeZero(const Value *V, unsigned Depth) {
if (const ConstantFP *CFP = dyn_cast<ConstantFP>(V))
return !CFP->getValueAPF().isNegZero();
-
+
if (Depth == 6)
return 1; // Limit search depth.
@@ -1397,19 +1397,19 @@
// (add x, 0.0) is guaranteed to return +0.0, not -0.0.
if (I->getOpcode() == Instruction::FAdd &&
- isa<ConstantFP>(I->getOperand(1)) &&
+ isa<ConstantFP>(I->getOperand(1)) &&
cast<ConstantFP>(I->getOperand(1))->isNullValue())
return true;
-
+
// sitofp and uitofp turn into +0.0 for zero.
if (isa<SIToFPInst>(I) || isa<UIToFPInst>(I))
return true;
-
+
if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(I))
// sqrt(-0.0) = -0.0, no other negative results are possible.
if (II->getIntrinsicID() == Intrinsic::sqrt)
return CannotBeNegativeZero(II->getArgOperand(0), Depth+1);
-
+
if (const CallInst *CI = dyn_cast<CallInst>(I))
if (const Function *F = CI->getCalledFunction()) {
if (F->isDeclaration()) {
@@ -1424,7 +1424,7 @@
return CannotBeNegativeZero(CI->getArgOperand(0), Depth+1);
}
}
-
+
return false;
}
@@ -1441,9 +1441,9 @@
if (Constant *C = dyn_cast<Constant>(V))
if (C->isNullValue())
return Constant::getNullValue(Type::getInt8Ty(V->getContext()));
-
+
// Constant float and double values can be handled as integer values if the
- // corresponding integer value is "byteable". An important case is 0.0.
+ // corresponding integer value is "byteable". An important case is 0.0.
if (ConstantFP *CFP = dyn_cast<ConstantFP>(V)) {
if (CFP->getType()->isFloatTy())
V = ConstantExpr::getBitCast(CFP, Type::getInt32Ty(V->getContext()));
@@ -1451,8 +1451,8 @@
V = ConstantExpr::getBitCast(CFP, Type::getInt64Ty(V->getContext()));
// Don't handle long double formats, which have strange constraints.
}
-
- // We can handle constant integers that are power of two in size and a
+
+ // We can handle constant integers that are power of two in size and a
// multiple of 8 bits.
if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
unsigned Width = CI->getBitWidth();
@@ -1466,7 +1466,7 @@
Val2 = Val.lshr(NextWidth);
Val2 = Val2.trunc(Val.getBitWidth()/2);
Val = Val.trunc(Val.getBitWidth()/2);
-
+
// If the top/bottom halves aren't the same, reject it.
if (Val != Val2)
return 0;
@@ -1474,7 +1474,7 @@
return ConstantInt::get(V->getContext(), Val);
}
}
-
+
// A ConstantDataArray/Vector is splatable if all its members are equal and
// also splatable.
if (ConstantDataSequential *CA = dyn_cast<ConstantDataSequential>(V)) {
@@ -1482,11 +1482,11 @@
Value *Val = isBytewiseValue(Elt);
if (!Val)
return 0;
-
+
for (unsigned I = 1, E = CA->getNumElements(); I != E; ++I)
if (CA->getElementAsConstant(I) != Elt)
return 0;
-
+
return Val;
}
@@ -1541,7 +1541,7 @@
// the struct's elements had a value that was inserted directly. In the latter
// case, perhaps we can't determine each of the subelements individually, but
// we might be able to find the complete struct somewhere.
-
+
// Find the value that is at that particular spot
Value *V = FindInsertedValue(From, Idxs);
@@ -1600,7 +1600,7 @@
if (C == 0) return 0;
return FindInsertedValue(C, idx_range.slice(1), InsertBefore);
}
-
+
if (InsertValueInst *I = dyn_cast<InsertValueInst>(V)) {
// Loop the indices for the insertvalue instruction in parallel with the
// requested indices
@@ -1625,7 +1625,7 @@
return BuildSubAggregate(V, makeArrayRef(idx_range.begin(), req_idx),
InsertBefore);
}
-
+
// This insert value inserts something else than what we are looking for.
// See if the (aggregrate) value inserted into has the value we are
// looking for, then.
@@ -1640,26 +1640,26 @@
makeArrayRef(req_idx, idx_range.end()),
InsertBefore);
}
-
+
if (ExtractValueInst *I = dyn_cast<ExtractValueInst>(V)) {
// If we're extracting a value from an aggregrate that was extracted from
// something else, we can extract from that something else directly instead.
// However, we will need to chain I's indices with the requested indices.
-
- // Calculate the number of indices required
+
+ // Calculate the number of indices required
unsigned size = I->getNumIndices() + idx_range.size();
// Allocate some space to put the new indices in
SmallVector<unsigned, 5> Idxs;
Idxs.reserve(size);
// Add indices from the extract value instruction
Idxs.append(I->idx_begin(), I->idx_end());
-
+
// Add requested indices
Idxs.append(idx_range.begin(), idx_range.end());
- assert(Idxs.size() == size
+ assert(Idxs.size() == size
&& "Number of indices added not correct?");
-
+
return FindInsertedValue(I->getAggregateOperand(), Idxs, InsertBefore);
}
// Otherwise, we don't know (such as, extracting from a function return value
@@ -1675,21 +1675,21 @@
Operator *PtrOp = dyn_cast<Operator>(Ptr);
if (PtrOp == 0 || Ptr->getType()->isVectorTy())
return Ptr;
-
+
// Just look through bitcasts.
if (PtrOp->getOpcode() == Instruction::BitCast)
return GetPointerBaseWithConstantOffset(PtrOp->getOperand(0), Offset, TD);
-
+
// If this is a GEP with constant indices, we can look through it.
GEPOperator *GEP = dyn_cast<GEPOperator>(PtrOp);
if (GEP == 0 || !GEP->hasAllConstantIndices()) return Ptr;
-
+
gep_type_iterator GTI = gep_type_begin(GEP);
for (User::op_iterator I = GEP->idx_begin(), E = GEP->idx_end(); I != E;
++I, ++GTI) {
ConstantInt *OpC = cast<ConstantInt>(*I);
if (OpC->isZero()) continue;
-
+
// Handle a struct and array indices which add their offset to the pointer.
if (StructType *STy = dyn_cast<StructType>(*GTI)) {
Offset += TD.getStructLayout(STy)->getElementOffset(OpC->getZExtValue());
@@ -1698,13 +1698,13 @@
Offset += OpC->getSExtValue()*Size;
}
}
-
+
// Re-sign extend from the pointer size if needed to get overflow edge cases
// right.
unsigned PtrSize = TD.getPointerSizeInBits();
if (PtrSize < 64)
Offset = SignExtend64(Offset, PtrSize);
-
+
return GetPointerBaseWithConstantOffset(GEP->getPointerOperand(), Offset, TD);
}
@@ -1718,26 +1718,26 @@
// Look through bitcast instructions and geps.
V = V->stripPointerCasts();
-
+
// If the value is a GEP instructionor constant expression, treat it as an
// offset.
if (const GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
// Make sure the GEP has exactly three arguments.
if (GEP->getNumOperands() != 3)
return false;
-
+
// Make sure the index-ee is a pointer to array of i8.
PointerType *PT = cast<PointerType>(GEP->getOperand(0)->getType());
ArrayType *AT = dyn_cast<ArrayType>(PT->getElementType());
if (AT == 0 || !AT->getElementType()->isIntegerTy(8))
return false;
-
+
// Check to make sure that the first operand of the GEP is an integer and
// has value 0 so that we are sure we're indexing into the initializer.
const ConstantInt *FirstIdx = dyn_cast<ConstantInt>(GEP->getOperand(1));
if (FirstIdx == 0 || !FirstIdx->isZero())
return false;
-
+
// If the second index isn't a ConstantInt, then this is a variable index
// into the array. If this occurs, we can't say anything meaningful about
// the string.
@@ -1763,13 +1763,13 @@
Str = "";
return true;
}
-
+
// Must be a Constant Array
const ConstantDataArray *Array =
dyn_cast<ConstantDataArray>(GV->getInitializer());
if (Array == 0 || !Array->isString())
return false;
-
+
// Get the number of elements in the array
uint64_t NumElts = Array->getType()->getArrayNumElements();
@@ -1778,10 +1778,10 @@
if (Offset > NumElts)
return false;
-
+
// Skip over 'offset' bytes.
Str = Str.substr(Offset);
-
+
if (TrimAtNul) {
// Trim off the \0 and anything after it. If the array is not nul
// terminated, we just return the whole end of string. The client may know
@@ -1835,7 +1835,7 @@
if (Len1 != Len2) return 0;
return Len1;
}
-
+
// Otherwise, see if we can read the string.
StringRef StrData;
if (!getConstantStringInfo(V, StrData))
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