diff options
Diffstat (limited to 'contrib/llvm/lib/Analysis/ValueTracking.cpp')
-rw-r--r-- | contrib/llvm/lib/Analysis/ValueTracking.cpp | 88 |
1 files changed, 69 insertions, 19 deletions
diff --git a/contrib/llvm/lib/Analysis/ValueTracking.cpp b/contrib/llvm/lib/Analysis/ValueTracking.cpp index 45dcc5e..e39ee62 100644 --- a/contrib/llvm/lib/Analysis/ValueTracking.cpp +++ b/contrib/llvm/lib/Analysis/ValueTracking.cpp @@ -15,6 +15,7 @@ #include "llvm/Analysis/ValueTracking.h" #include "llvm/ADT/SmallPtrSet.h" #include "llvm/Analysis/InstructionSimplify.h" +#include "llvm/Analysis/MemoryBuiltins.h" #include "llvm/IR/Constants.h" #include "llvm/IR/DataLayout.h" #include "llvm/IR/GlobalAlias.h" @@ -39,8 +40,8 @@ const unsigned MaxDepth = 6; static unsigned getBitWidth(Type *Ty, const DataLayout *TD) { if (unsigned BitWidth = Ty->getScalarSizeInBits()) return BitWidth; - assert(isa<PointerType>(Ty) && "Expected a pointer type!"); - return TD ? TD->getPointerSizeInBits() : 0; + + return TD ? TD->getPointerTypeSizeInBits(Ty) : 0; } static void ComputeMaskedBitsAddSub(bool Add, Value *Op0, Value *Op1, bool NSW, @@ -290,7 +291,7 @@ void llvm::ComputeMaskedBits(Value *V, APInt &KnownZero, APInt &KnownOne, } if (Align > 0) KnownZero = APInt::getLowBitsSet(BitWidth, - CountTrailingZeros_32(Align)); + countTrailingZeros(Align)); else KnownZero.clearAllBits(); KnownOne.clearAllBits(); @@ -321,7 +322,7 @@ void llvm::ComputeMaskedBits(Value *V, APInt &KnownZero, APInt &KnownOne, } if (Align) - KnownZero = APInt::getLowBitsSet(BitWidth, CountTrailingZeros_32(Align)); + KnownZero = APInt::getLowBitsSet(BitWidth, countTrailingZeros(Align)); return; } @@ -613,7 +614,7 @@ void llvm::ComputeMaskedBits(Value *V, APInt &KnownZero, APInt &KnownOne, Align = TD->getABITypeAlignment(AI->getType()->getElementType()); if (Align > 0) - KnownZero = APInt::getLowBitsSet(BitWidth, CountTrailingZeros_32(Align)); + KnownZero = APInt::getLowBitsSet(BitWidth, countTrailingZeros(Align)); break; } case Instruction::GetElementPtr: { @@ -629,12 +630,22 @@ void llvm::ComputeMaskedBits(Value *V, APInt &KnownZero, APInt &KnownOne, Value *Index = I->getOperand(i); if (StructType *STy = dyn_cast<StructType>(*GTI)) { // Handle struct member offset arithmetic. - if (!TD) return; - const StructLayout *SL = TD->getStructLayout(STy); + if (!TD) + return; + + // Handle case when index is vector zeroinitializer + Constant *CIndex = cast<Constant>(Index); + if (CIndex->isZeroValue()) + continue; + + if (CIndex->getType()->isVectorTy()) + Index = CIndex->getSplatValue(); + unsigned Idx = cast<ConstantInt>(Index)->getZExtValue(); + const StructLayout *SL = TD->getStructLayout(STy); uint64_t Offset = SL->getElementOffset(Idx); - TrailZ = std::min(TrailZ, - CountTrailingZeros_64(Offset)); + TrailZ = std::min<unsigned>(TrailZ, + countTrailingZeros(Offset)); } else { // Handle array index arithmetic. Type *IndexedTy = GTI.getIndexedType(); @@ -644,7 +655,7 @@ void llvm::ComputeMaskedBits(Value *V, APInt &KnownZero, APInt &KnownOne, LocalKnownZero = LocalKnownOne = APInt(GEPOpiBits, 0); ComputeMaskedBits(Index, LocalKnownZero, LocalKnownOne, TD, Depth+1); TrailZ = std::min(TrailZ, - unsigned(CountTrailingZeros_64(TypeSize) + + unsigned(countTrailingZeros(TypeSize) + LocalKnownZero.countTrailingOnes())); } } @@ -749,7 +760,6 @@ void llvm::ComputeMaskedBits(Value *V, APInt &KnownZero, APInt &KnownOne, 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; @@ -855,6 +865,37 @@ bool llvm::isKnownToBeAPowerOfTwo(Value *V, bool OrZero, unsigned Depth) { return false; } + // Adding a power-of-two or zero to the same power-of-two or zero yields + // either the original power-of-two, a larger power-of-two or zero. + if (match(V, m_Add(m_Value(X), m_Value(Y)))) { + OverflowingBinaryOperator *VOBO = cast<OverflowingBinaryOperator>(V); + if (OrZero || VOBO->hasNoUnsignedWrap() || VOBO->hasNoSignedWrap()) { + if (match(X, m_And(m_Specific(Y), m_Value())) || + match(X, m_And(m_Value(), m_Specific(Y)))) + if (isKnownToBeAPowerOfTwo(Y, OrZero, Depth)) + return true; + if (match(Y, m_And(m_Specific(X), m_Value())) || + match(Y, m_And(m_Value(), m_Specific(X)))) + if (isKnownToBeAPowerOfTwo(X, OrZero, Depth)) + return true; + + unsigned BitWidth = V->getType()->getScalarSizeInBits(); + APInt LHSZeroBits(BitWidth, 0), LHSOneBits(BitWidth, 0); + ComputeMaskedBits(X, LHSZeroBits, LHSOneBits, 0, Depth); + + APInt RHSZeroBits(BitWidth, 0), RHSOneBits(BitWidth, 0); + ComputeMaskedBits(Y, RHSZeroBits, RHSOneBits, 0, Depth); + // If i8 V is a power of two or zero: + // ZeroBits: 1 1 1 0 1 1 1 1 + // ~ZeroBits: 0 0 0 1 0 0 0 0 + if ((~(LHSZeroBits & RHSZeroBits)).isPowerOf2()) + // If OrZero isn't set, we cannot give back a zero result. + // Make sure either the LHS or RHS has a bit set. + if (OrZero || RHSOneBits.getBoolValue() || LHSOneBits.getBoolValue()) + return true; + } + } + // 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). @@ -1509,7 +1550,7 @@ Value *llvm::isBytewiseValue(Value *V) { // struct. To is the result struct built so far, new insertvalue instructions // build on that. static Value *BuildSubAggregate(Value *From, Value* To, Type *IndexedType, - SmallVector<unsigned, 10> &Idxs, + SmallVectorImpl<unsigned> &Idxs, unsigned IdxSkip, Instruction *InsertBefore) { llvm::StructType *STy = dyn_cast<llvm::StructType>(IndexedType); @@ -1673,20 +1714,24 @@ Value *llvm::FindInsertedValue(Value *V, ArrayRef<unsigned> idx_range, /// it can be expressed as a base pointer plus a constant offset. Return the /// base and offset to the caller. Value *llvm::GetPointerBaseWithConstantOffset(Value *Ptr, int64_t &Offset, - const DataLayout *TD) { + const DataLayout *DL) { // Without DataLayout, conservatively assume 64-bit offsets, which is // the widest we support. - unsigned BitWidth = TD ? TD->getPointerSizeInBits() : 64; + unsigned BitWidth = DL ? DL->getPointerTypeSizeInBits(Ptr->getType()) : 64; APInt ByteOffset(BitWidth, 0); while (1) { if (Ptr->getType()->isVectorTy()) break; if (GEPOperator *GEP = dyn_cast<GEPOperator>(Ptr)) { - APInt GEPOffset(BitWidth, 0); - if (TD && !GEP->accumulateConstantOffset(*TD, GEPOffset)) - break; - ByteOffset += GEPOffset; + if (DL) { + APInt GEPOffset(BitWidth, 0); + if (!GEP->accumulateConstantOffset(*DL, GEPOffset)) + break; + + ByteOffset += GEPOffset; + } + Ptr = GEP->getPointerOperand(); } else if (Operator::getOpcode(Ptr) == Instruction::BitCast) { Ptr = cast<Operator>(Ptr)->getOperand(0); @@ -2019,7 +2064,7 @@ bool llvm::isSafeToSpeculativelyExecute(const Value *V, /// isKnownNonNull - Return true if we know that the specified value is never /// null. -bool llvm::isKnownNonNull(const Value *V) { +bool llvm::isKnownNonNull(const Value *V, const TargetLibraryInfo *TLI) { // Alloca never returns null, malloc might. if (isa<AllocaInst>(V)) return true; @@ -2030,5 +2075,10 @@ bool llvm::isKnownNonNull(const Value *V) { // Global values are not null unless extern weak. if (const GlobalValue *GV = dyn_cast<GlobalValue>(V)) return !GV->hasExternalWeakLinkage(); + + // operator new never returns null. + if (isOperatorNewLikeFn(V, TLI, /*LookThroughBitCast=*/true)) + return true; + return false; } |