#include "llvm/Target/TargetData.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/PatternMatch.h"
#include "llvm/ADT/SmallPtrSet.h"
#include <cstring>
using namespace llvm;
+using namespace llvm::PatternMatch;
+
+const unsigned MaxDepth = 6;
+
+/// getBitWidth - Returns the bitwidth of the given scalar or pointer type (if
+/// unknown returns 0). For vector types, returns the element type's bitwidth.
+static unsigned getBitWidth(Type *Ty, const TargetData *TD) {
+ if (unsigned BitWidth = Ty->getScalarSizeInBits())
+ return BitWidth;
+ assert(isa<PointerType>(Ty) && "Expected a pointer type!");
+ return TD ? TD->getPointerSizeInBits() : 0;
+}
/// ComputeMaskedBits - Determine which of the bits specified in Mask are
/// known to be either zero or one and return them in the KnownZero/KnownOne
void llvm::ComputeMaskedBits(Value *V, const APInt &Mask,
APInt &KnownZero, APInt &KnownOne,
const TargetData *TD, unsigned Depth) {
- const unsigned MaxDepth = 6;
assert(V && "No Value?");
assert(Depth <= MaxDepth && "Limit Search Depth");
unsigned BitWidth = Mask.getBitWidth();
if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
unsigned Align = GV->getAlignment();
if (Align == 0 && TD && GV->getType()->getElementType()->isSized()) {
- const Type *ObjectType = GV->getType()->getElementType();
+ Type *ObjectType = GV->getType()->getElementType();
// If the object is defined in the current Module, we'll be giving
// it the preferred alignment. Otherwise, we have to assume that it
// may only have the minimum ABI alignment.
}
return;
}
+
+ if (Argument *A = dyn_cast<Argument>(V)) {
+ // Get alignment information off byval arguments if specified in the IR.
+ if (A->hasByValAttr())
+ if (unsigned Align = A->getParamAlignment())
+ KnownZero = Mask & APInt::getLowBitsSet(BitWidth,
+ CountTrailingZeros_32(Align));
+ return;
+ }
- KnownZero.clearAllBits(); KnownOne.clearAllBits(); // Start out not knowing anything.
+ // Start out not knowing anything.
+ KnownZero.clearAllBits(); KnownOne.clearAllBits();
if (Depth == MaxDepth || Mask == 0)
return; // Limit search depth.
// FALL THROUGH and handle them the same as zext/trunc.
case Instruction::ZExt:
case Instruction::Trunc: {
- const Type *SrcTy = I->getOperand(0)->getType();
+ Type *SrcTy = I->getOperand(0)->getType();
unsigned SrcBitWidth;
// Note that we handle pointer operands here because of inttoptr/ptrtoint
return;
}
case Instruction::BitCast: {
- const Type *SrcTy = I->getOperand(0)->getType();
+ Type *SrcTy = I->getOperand(0)->getType();
if ((SrcTy->isIntegerTy() || SrcTy->isPointerTy()) &&
// TODO: For now, not handling conversions like:
// (bitcast i64 %x to <2 x i32>)
// (ashr X, C1) & C2 == 0 iff (-1 >> C1) & C2 == 0
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);
+ uint64_t ShiftAmt = SA->getLimitedValue(BitWidth-1);
// Signed shift right.
APInt Mask2(Mask.shl(ShiftAmt));
KnownZero |= LHSKnownZero & Mask;
KnownOne |= LHSKnownOne & Mask;
}
+
+ // Are we still trying to solve for the sign bit?
+ if (Mask.isNegative() && !KnownZero.isNegative() && !KnownOne.isNegative()){
+ OverflowingBinaryOperator *OBO = cast<OverflowingBinaryOperator>(I);
+ if (OBO->hasNoSignedWrap()) {
+ if (I->getOpcode() == Instruction::Add) {
+ // Adding two positive numbers can't wrap into negative
+ if (LHSKnownZero.isNegative() && KnownZero2.isNegative())
+ KnownZero |= APInt::getSignBit(BitWidth);
+ // and adding two negative numbers can't wrap into positive.
+ else if (LHSKnownOne.isNegative() && KnownOne2.isNegative())
+ KnownOne |= APInt::getSignBit(BitWidth);
+ } else {
+ // Subtracting a negative number from a positive one can't wrap
+ if (LHSKnownZero.isNegative() && KnownOne2.isNegative())
+ KnownZero |= APInt::getSignBit(BitWidth);
+ // neither can subtracting a positive number from a negative one.
+ else if (LHSKnownOne.isNegative() && KnownZero2.isNegative())
+ KnownOne |= APInt::getSignBit(BitWidth);
+ }
+ }
+ }
+
return;
}
case Instruction::SRem:
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
}
}
+
+ // The sign bit is the LHS's sign bit, except when the result of the
+ // remainder is zero.
+ if (Mask.isNegative() && KnownZero.isNonNegative()) {
+ APInt Mask2 = APInt::getSignBit(BitWidth);
+ APInt LHSKnownZero(BitWidth, 0), LHSKnownOne(BitWidth, 0);
+ ComputeMaskedBits(I->getOperand(0), Mask2, LHSKnownZero, LHSKnownOne, TD,
+ Depth+1);
+ // If it's known zero, our sign bit is also zero.
+ if (LHSKnownZero.isNegative())
+ KnownZero |= LHSKnownZero;
+ }
+
break;
case Instruction::URem: {
if (ConstantInt *Rem = dyn_cast<ConstantInt>(I->getOperand(1))) {
gep_type_iterator GTI = gep_type_begin(I);
for (unsigned i = 1, e = I->getNumOperands(); i != e; ++i, ++GTI) {
Value *Index = I->getOperand(i);
- if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
+ if (StructType *STy = dyn_cast<StructType>(*GTI)) {
// Handle struct member offset arithmetic.
if (!TD) return;
const StructLayout *SL = TD->getStructLayout(STy);
CountTrailingZeros_64(Offset));
} else {
// Handle array index arithmetic.
- const Type *IndexedTy = GTI.getIndexedType();
+ Type *IndexedTy = GTI.getIndexedType();
if (!IndexedTy->isSized()) return;
unsigned GEPOpiBits = Index->getType()->getScalarSizeInBits();
uint64_t TypeSize = TD ? TD->getTypeAllocSize(IndexedTy) : 1;
}
}
+ // Unreachable blocks may have zero-operand PHI nodes.
+ if (P->getNumIncomingValues() == 0)
+ return;
+
// Otherwise take the unions of the known bit sets of the operands,
// taking conservative care to avoid excessive recursion.
if (Depth < MaxDepth - 1 && !KnownZero && !KnownOne) {
+ // Skip if every incoming value references to ourself.
+ if (P->hasConstantValue() == P)
+ break;
+
KnownZero = APInt::getAllOnesValue(BitWidth);
KnownOne = APInt::getAllOnesValue(BitWidth);
for (unsigned i = 0, e = P->getNumIncomingValues(); i != e; ++i) {
KnownZero = APInt::getHighBitsSet(BitWidth, BitWidth - LowBits);
break;
}
+ case Intrinsic::x86_sse42_crc32_64_8:
+ case Intrinsic::x86_sse42_crc32_64_64:
+ KnownZero = APInt::getHighBitsSet(64, 32);
+ break;
}
}
break;
}
}
+/// ComputeSignBit - Determine whether the sign bit is known to be zero or
+/// one. Convenience wrapper around ComputeMaskedBits.
+void llvm::ComputeSignBit(Value *V, bool &KnownZero, bool &KnownOne,
+ const TargetData *TD, unsigned Depth) {
+ unsigned BitWidth = getBitWidth(V->getType(), TD);
+ if (!BitWidth) {
+ KnownZero = false;
+ KnownOne = false;
+ return;
+ }
+ APInt ZeroBits(BitWidth, 0);
+ APInt OneBits(BitWidth, 0);
+ ComputeMaskedBits(V, APInt::getSignBit(BitWidth), ZeroBits, OneBits, TD,
+ Depth);
+ KnownOne = OneBits[BitWidth - 1];
+ KnownZero = ZeroBits[BitWidth - 1];
+}
+
+/// isPowerOfTwo - Return true if the given value is known to have exactly one
+/// bit set when defined. For vectors return true if every element is known to
+/// be a power of two when defined. Supports values with integer or pointer
+/// types and vectors of integers.
+bool llvm::isPowerOfTwo(Value *V, const TargetData *TD, unsigned Depth) {
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(V))
+ return CI->getValue().isPowerOf2();
+ // TODO: Handle vector constants.
+
+ // 1 << X is clearly a power of two if the one is not shifted off the end. If
+ // it is shifted off the end then the result is undefined.
+ if (match(V, m_Shl(m_One(), m_Value())))
+ return true;
+
+ // (signbit) >>l X is clearly a power of two if the one is not shifted off the
+ // bottom. If it is shifted off the bottom then the result is undefined.
+ if (match(V, m_LShr(m_SignBit(), m_Value())))
+ return true;
+
+ // The remaining tests are all recursive, so bail out if we hit the limit.
+ if (Depth++ == MaxDepth)
+ return false;
+
+ if (ZExtInst *ZI = dyn_cast<ZExtInst>(V))
+ return isPowerOfTwo(ZI->getOperand(0), TD, Depth);
+
+ if (SelectInst *SI = dyn_cast<SelectInst>(V))
+ return isPowerOfTwo(SI->getTrueValue(), TD, Depth) &&
+ isPowerOfTwo(SI->getFalseValue(), TD, Depth);
+
+ // An exact divide or right shift can only shift off zero bits, so the result
+ // is a power of two only if the first operand is a power of two and not
+ // copying a sign bit (sdiv int_min, 2).
+ if (match(V, m_LShr(m_Value(), m_Value())) ||
+ match(V, m_UDiv(m_Value(), m_Value()))) {
+ PossiblyExactOperator *PEO = cast<PossiblyExactOperator>(V);
+ if (PEO->isExact())
+ return isPowerOfTwo(PEO->getOperand(0), TD, Depth);
+ }
+
+ return false;
+}
+
+/// isKnownNonZero - Return true if the given value is known to be non-zero
+/// when defined. For vectors return true if every element is known to be
+/// non-zero when defined. Supports values with integer or pointer type and
+/// vectors of integers.
+bool llvm::isKnownNonZero(Value *V, const TargetData *TD, unsigned Depth) {
+ if (Constant *C = dyn_cast<Constant>(V)) {
+ if (C->isNullValue())
+ return false;
+ if (isa<ConstantInt>(C))
+ // Must be non-zero due to null test above.
+ return true;
+ // TODO: Handle vectors
+ return false;
+ }
+
+ // The remaining tests are all recursive, so bail out if we hit the limit.
+ if (Depth++ == MaxDepth)
+ return false;
+
+ unsigned BitWidth = getBitWidth(V->getType(), TD);
+
+ // X | Y != 0 if X != 0 or Y != 0.
+ Value *X = 0, *Y = 0;
+ if (match(V, m_Or(m_Value(X), m_Value(Y))))
+ return isKnownNonZero(X, TD, Depth) || isKnownNonZero(Y, TD, Depth);
+
+ // ext X != 0 if X != 0.
+ if (isa<SExtInst>(V) || isa<ZExtInst>(V))
+ return isKnownNonZero(cast<Instruction>(V)->getOperand(0), TD, Depth);
+
+ // shl X, Y != 0 if X is odd. Note that the value of the shift is undefined
+ // if the lowest bit is shifted off the end.
+ if (BitWidth && match(V, m_Shl(m_Value(X), m_Value(Y)))) {
+ // shl nuw can't remove any non-zero bits.
+ BinaryOperator *BO = cast<BinaryOperator>(V);
+ if (BO->hasNoUnsignedWrap())
+ return isKnownNonZero(X, TD, Depth);
+
+ APInt KnownZero(BitWidth, 0);
+ APInt KnownOne(BitWidth, 0);
+ ComputeMaskedBits(X, APInt(BitWidth, 1), KnownZero, KnownOne, TD, Depth);
+ if (KnownOne[0])
+ return true;
+ }
+ // shr X, Y != 0 if X is negative. Note that the value of the shift is not
+ // defined if the sign bit is shifted off the end.
+ else if (match(V, m_Shr(m_Value(X), m_Value(Y)))) {
+ // shr exact can only shift out zero bits.
+ BinaryOperator *BO = cast<BinaryOperator>(V);
+ if (BO->isExact())
+ return isKnownNonZero(X, TD, Depth);
+
+ bool XKnownNonNegative, XKnownNegative;
+ ComputeSignBit(X, XKnownNonNegative, XKnownNegative, TD, Depth);
+ if (XKnownNegative)
+ return true;
+ }
+ // div exact can only produce a zero if the dividend is zero.
+ else if (match(V, m_IDiv(m_Value(X), m_Value()))) {
+ BinaryOperator *BO = cast<BinaryOperator>(V);
+ if (BO->isExact())
+ return isKnownNonZero(X, TD, Depth);
+ }
+ // X + Y.
+ else if (match(V, m_Add(m_Value(X), m_Value(Y)))) {
+ bool XKnownNonNegative, XKnownNegative;
+ bool YKnownNonNegative, YKnownNegative;
+ ComputeSignBit(X, XKnownNonNegative, XKnownNegative, TD, Depth);
+ ComputeSignBit(Y, YKnownNonNegative, YKnownNegative, TD, Depth);
+
+ // If X and Y are both non-negative (as signed values) then their sum is not
+ // zero unless both X and Y are zero.
+ if (XKnownNonNegative && YKnownNonNegative)
+ if (isKnownNonZero(X, TD, Depth) || isKnownNonZero(Y, TD, Depth))
+ return true;
+
+ // If X and Y are both negative (as signed values) then their sum is not
+ // zero unless both X and Y equal INT_MIN.
+ if (BitWidth && XKnownNegative && YKnownNegative) {
+ APInt KnownZero(BitWidth, 0);
+ APInt KnownOne(BitWidth, 0);
+ APInt Mask = APInt::getSignedMaxValue(BitWidth);
+ // The sign bit of X is set. If some other bit is set then X is not equal
+ // to INT_MIN.
+ ComputeMaskedBits(X, Mask, KnownZero, KnownOne, TD, Depth);
+ if ((KnownOne & Mask) != 0)
+ return true;
+ // The sign bit of Y is set. If some other bit is set then Y is not equal
+ // to INT_MIN.
+ ComputeMaskedBits(Y, Mask, KnownZero, KnownOne, TD, Depth);
+ if ((KnownOne & Mask) != 0)
+ return true;
+ }
+
+ // The sum of a non-negative number and a power of two is not zero.
+ if (XKnownNonNegative && isPowerOfTwo(Y, TD, Depth))
+ return true;
+ if (YKnownNonNegative && isPowerOfTwo(X, TD, Depth))
+ return true;
+ }
+ // (C ? X : Y) != 0 if X != 0 and Y != 0.
+ else if (SelectInst *SI = dyn_cast<SelectInst>(V)) {
+ if (isKnownNonZero(SI->getTrueValue(), TD, Depth) &&
+ isKnownNonZero(SI->getFalseValue(), TD, Depth))
+ return true;
+ }
+
+ if (!BitWidth) return false;
+ APInt KnownZero(BitWidth, 0);
+ APInt KnownOne(BitWidth, 0);
+ ComputeMaskedBits(V, APInt::getAllOnesValue(BitWidth), KnownZero, KnownOne,
+ TD, Depth);
+ return KnownOne != 0;
+}
+
/// MaskedValueIsZero - Return true if 'V & Mask' is known to be zero. We use
/// this predicate to simplify operations downstream. Mask is known to be zero
/// for bits that V cannot have.
assert((TD || V->getType()->isIntOrIntVectorTy()) &&
"ComputeNumSignBits requires a TargetData object to operate "
"on non-integer values!");
- const Type *Ty = V->getType();
+ Type *Ty = V->getType();
unsigned TyBits = TD ? TD->getTypeSizeInBits(V->getType()->getScalarType()) :
Ty->getScalarSizeInBits();
unsigned Tmp, Tmp2;
assert(Depth <= MaxDepth && "Limit Search Depth");
assert(V->getType()->isIntegerTy() && "Not integer or pointer type!");
- const Type *T = V->getType();
+ Type *T = V->getType();
ConstantInt *CI = dyn_cast<ConstantInt>(V);
Value *llvm::isBytewiseValue(Value *V) {
// All byte-wide stores are splatable, even of arbitrary variables.
if (V->getType()->isIntegerTy(8)) return V;
+
+ // Handle 'null' ConstantArrayZero etc.
+ 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.
// indices from Idxs that should be left out when inserting into the resulting
// struct. To is the result struct built so far, new insertvalue instructions
// build on that.
-static Value *BuildSubAggregate(Value *From, Value* To, const Type *IndexedType,
+static Value *BuildSubAggregate(Value *From, Value* To, Type *IndexedType,
SmallVector<unsigned, 10> &Idxs,
unsigned IdxSkip,
Instruction *InsertBefore) {
- const llvm::StructType *STy = llvm::dyn_cast<llvm::StructType>(IndexedType);
+ llvm::StructType *STy = llvm::dyn_cast<llvm::StructType>(IndexedType);
if (STy) {
// Save the original To argument so we can modify it
Value *OrigTo = To;
break;
}
}
- // If we succesfully found a value for each of our subaggregates
+ // If we successfully found a value for each of our subaggregates
if (To)
return To;
}
// we might be able to find the complete struct somewhere.
// Find the value that is at that particular spot
- Value *V = FindInsertedValue(From, Idxs.begin(), Idxs.end());
+ Value *V = FindInsertedValue(From, Idxs);
if (!V)
return NULL;
// Insert the value in the new (sub) aggregrate
- return llvm::InsertValueInst::Create(To, V, Idxs.begin() + IdxSkip,
- Idxs.end(), "tmp", InsertBefore);
+ return llvm::InsertValueInst::Create(To, V, makeArrayRef(Idxs).slice(IdxSkip),
+ "tmp", InsertBefore);
}
// This helper takes a nested struct and extracts a part of it (which is again a
// insertvalue instruction somewhere).
//
// All inserted insertvalue instructions are inserted before InsertBefore
-static Value *BuildSubAggregate(Value *From, const unsigned *idx_begin,
- const unsigned *idx_end,
+static Value *BuildSubAggregate(Value *From, ArrayRef<unsigned> idx_range,
Instruction *InsertBefore) {
assert(InsertBefore && "Must have someplace to insert!");
- const Type *IndexedType = ExtractValueInst::getIndexedType(From->getType(),
- idx_begin,
- idx_end);
+ Type *IndexedType = ExtractValueInst::getIndexedType(From->getType(),
+ idx_range);
Value *To = UndefValue::get(IndexedType);
- SmallVector<unsigned, 10> Idxs(idx_begin, idx_end);
+ SmallVector<unsigned, 10> Idxs(idx_range.begin(), idx_range.end());
unsigned IdxSkip = Idxs.size();
return BuildSubAggregate(From, To, IndexedType, Idxs, IdxSkip, InsertBefore);
///
/// If InsertBefore is not null, this function will duplicate (modified)
/// insertvalues when a part of a nested struct is extracted.
-Value *llvm::FindInsertedValue(Value *V, const unsigned *idx_begin,
- const unsigned *idx_end, Instruction *InsertBefore) {
+Value *llvm::FindInsertedValue(Value *V, ArrayRef<unsigned> idx_range,
+ Instruction *InsertBefore) {
// Nothing to index? Just return V then (this is useful at the end of our
// recursion)
- if (idx_begin == idx_end)
+ if (idx_range.empty())
return V;
// We have indices, so V should have an indexable type
assert((V->getType()->isStructTy() || V->getType()->isArrayTy())
&& "Not looking at a struct or array?");
- assert(ExtractValueInst::getIndexedType(V->getType(), idx_begin, idx_end)
+ assert(ExtractValueInst::getIndexedType(V->getType(), idx_range)
&& "Invalid indices for type?");
- const CompositeType *PTy = cast<CompositeType>(V->getType());
+ CompositeType *PTy = cast<CompositeType>(V->getType());
if (isa<UndefValue>(V))
return UndefValue::get(ExtractValueInst::getIndexedType(PTy,
- idx_begin,
- idx_end));
+ idx_range));
else if (isa<ConstantAggregateZero>(V))
return Constant::getNullValue(ExtractValueInst::getIndexedType(PTy,
- idx_begin,
- idx_end));
+ idx_range));
else if (Constant *C = dyn_cast<Constant>(V)) {
if (isa<ConstantArray>(C) || isa<ConstantStruct>(C))
// Recursively process this constant
- return FindInsertedValue(C->getOperand(*idx_begin), idx_begin + 1,
- idx_end, InsertBefore);
+ return FindInsertedValue(C->getOperand(idx_range[0]), idx_range.slice(1),
+ InsertBefore);
} else if (InsertValueInst *I = dyn_cast<InsertValueInst>(V)) {
// Loop the indices for the insertvalue instruction in parallel with the
// requested indices
- const unsigned *req_idx = idx_begin;
+ const unsigned *req_idx = idx_range.begin();
for (const unsigned *i = I->idx_begin(), *e = I->idx_end();
i != e; ++i, ++req_idx) {
- if (req_idx == idx_end) {
+ if (req_idx == idx_range.end()) {
if (InsertBefore)
// The requested index identifies a part of a nested aggregate. Handle
// this specially. For example,
// %C = insertvalue {i32, i32 } %A, i32 11, 1
// which allows the unused 0,0 element from the nested struct to be
// removed.
- return BuildSubAggregate(V, idx_begin, req_idx, InsertBefore);
+ return BuildSubAggregate(V, makeArrayRef(idx_range.begin(), req_idx),
+ InsertBefore);
else
// We can't handle this without inserting insertvalues
return 0;
// See if the (aggregrate) value inserted into has the value we are
// looking for, then.
if (*req_idx != *i)
- return FindInsertedValue(I->getAggregateOperand(), idx_begin, idx_end,
+ return FindInsertedValue(I->getAggregateOperand(), idx_range,
InsertBefore);
}
// If we end up here, the indices of the insertvalue match with those
// requested (though possibly only partially). Now we recursively look at
// the inserted value, passing any remaining indices.
- return FindInsertedValue(I->getInsertedValueOperand(), req_idx, idx_end,
+ return FindInsertedValue(I->getInsertedValueOperand(),
+ makeArrayRef(req_idx, idx_range.end()),
InsertBefore);
} else if (ExtractValueInst *I = dyn_cast<ExtractValueInst>(V)) {
// If we're extracting a value from an aggregrate that was extracted from
// However, we will need to chain I's indices with the requested indices.
// Calculate the number of indices required
- unsigned size = I->getNumIndices() + (idx_end - idx_begin);
+ 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
- for (const unsigned *i = I->idx_begin(), *e = I->idx_end();
- i != e; ++i)
- Idxs.push_back(*i);
+ Idxs.append(I->idx_begin(), I->idx_end());
// Add requested indices
- for (const unsigned *i = idx_begin, *e = idx_end; i != e; ++i)
- Idxs.push_back(*i);
+ Idxs.append(idx_range.begin(), idx_range.end());
assert(Idxs.size() == size
&& "Number of indices added not correct?");
- return FindInsertedValue(I->getAggregateOperand(), Idxs.begin(), Idxs.end(),
- InsertBefore);
+ return FindInsertedValue(I->getAggregateOperand(), Idxs, InsertBefore);
}
// Otherwise, we don't know (such as, extracting from a function return value
// or load instruction)
if (OpC->isZero()) continue;
// Handle a struct and array indices which add their offset to the pointer.
- if (const StructType *STy = dyn_cast<StructType>(*GTI)) {
+ if (StructType *STy = dyn_cast<StructType>(*GTI)) {
Offset += TD.getStructLayout(STy)->getElementOffset(OpC->getZExtValue());
} else {
uint64_t Size = TD.getTypeAllocSize(GTI.getIndexedType());
return false;
// Make sure the index-ee is a pointer to array of i8.
- const PointerType *PT = cast<PointerType>(GEP->getOperand(0)->getType());
- const ArrayType *AT = dyn_cast<ArrayType>(PT->getElementType());
+ PointerType *PT = cast<PointerType>(GEP->getOperand(0)->getType());
+ ArrayType *AT = dyn_cast<ArrayType>(PT->getElementType());
if (AT == 0 || !AT->getElementType()->isIntegerTy(8))
return false;
return Len == ~0ULL ? 1 : Len;
}
-Value *llvm::GetUnderlyingObject(Value *V, unsigned MaxLookup) {
+Value *
+llvm::GetUnderlyingObject(Value *V, const TargetData *TD, unsigned MaxLookup) {
if (!V->getType()->isPointerTy())
return V;
for (unsigned Count = 0; MaxLookup == 0 || Count < MaxLookup; ++Count) {
} else {
// See if InstructionSimplify knows any relevant tricks.
if (Instruction *I = dyn_cast<Instruction>(V))
- // TODO: Aquire TargetData and DominatorTree and use them.
- if (Value *Simplified = SimplifyInstruction(I, 0, 0)) {
+ // TODO: Acquire a DominatorTree and use it.
+ if (Value *Simplified = SimplifyInstruction(I, TD, 0)) {
V = Simplified;
continue;
}
}
return V;
}
+
+/// onlyUsedByLifetimeMarkers - Return true if the only users of this pointer
+/// are lifetime markers.
+///
+bool llvm::onlyUsedByLifetimeMarkers(const Value *V) {
+ for (Value::const_use_iterator UI = V->use_begin(), UE = V->use_end();
+ UI != UE; ++UI) {
+ const IntrinsicInst *II = dyn_cast<IntrinsicInst>(*UI);
+ if (!II) return false;
+
+ if (II->getIntrinsicID() != Intrinsic::lifetime_start &&
+ II->getIntrinsicID() != Intrinsic::lifetime_end)
+ return false;
+ }
+ return true;
+}