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Diffstat (limited to 'contrib/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp')
-rw-r--r-- | contrib/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp | 434 |
1 files changed, 434 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp b/contrib/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp new file mode 100644 index 0000000..1e7d942 --- /dev/null +++ b/contrib/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp @@ -0,0 +1,434 @@ +//===-- X86ShuffleDecode.cpp - X86 shuffle decode logic -------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// Define several functions to decode x86 specific shuffle semantics into a +// generic vector mask. +// +//===----------------------------------------------------------------------===// + +#include "X86ShuffleDecode.h" +#include "llvm/IR/Constants.h" +#include "llvm/CodeGen/MachineValueType.h" + +//===----------------------------------------------------------------------===// +// Vector Mask Decoding +//===----------------------------------------------------------------------===// + +namespace llvm { + +void DecodeINSERTPSMask(unsigned Imm, SmallVectorImpl<int> &ShuffleMask) { + // Defaults the copying the dest value. + ShuffleMask.push_back(0); + ShuffleMask.push_back(1); + ShuffleMask.push_back(2); + ShuffleMask.push_back(3); + + // Decode the immediate. + unsigned ZMask = Imm & 15; + unsigned CountD = (Imm >> 4) & 3; + unsigned CountS = (Imm >> 6) & 3; + + // CountS selects which input element to use. + unsigned InVal = 4 + CountS; + // CountD specifies which element of destination to update. + ShuffleMask[CountD] = InVal; + // ZMask zaps values, potentially overriding the CountD elt. + if (ZMask & 1) ShuffleMask[0] = SM_SentinelZero; + if (ZMask & 2) ShuffleMask[1] = SM_SentinelZero; + if (ZMask & 4) ShuffleMask[2] = SM_SentinelZero; + if (ZMask & 8) ShuffleMask[3] = SM_SentinelZero; +} + +// <3,1> or <6,7,2,3> +void DecodeMOVHLPSMask(unsigned NElts, SmallVectorImpl<int> &ShuffleMask) { + for (unsigned i = NElts / 2; i != NElts; ++i) + ShuffleMask.push_back(NElts + i); + + for (unsigned i = NElts / 2; i != NElts; ++i) + ShuffleMask.push_back(i); +} + +// <0,2> or <0,1,4,5> +void DecodeMOVLHPSMask(unsigned NElts, SmallVectorImpl<int> &ShuffleMask) { + for (unsigned i = 0; i != NElts / 2; ++i) + ShuffleMask.push_back(i); + + for (unsigned i = 0; i != NElts / 2; ++i) + ShuffleMask.push_back(NElts + i); +} + +void DecodeMOVSLDUPMask(MVT VT, SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + for (int i = 0, e = NumElts / 2; i < e; ++i) { + ShuffleMask.push_back(2 * i); + ShuffleMask.push_back(2 * i); + } +} + +void DecodeMOVSHDUPMask(MVT VT, SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + for (int i = 0, e = NumElts / 2; i < e; ++i) { + ShuffleMask.push_back(2 * i + 1); + ShuffleMask.push_back(2 * i + 1); + } +} + +void DecodeMOVDDUPMask(MVT VT, SmallVectorImpl<int> &ShuffleMask) { + unsigned VectorSizeInBits = VT.getSizeInBits(); + unsigned ScalarSizeInBits = VT.getScalarSizeInBits(); + unsigned NumElts = VT.getVectorNumElements(); + unsigned NumLanes = VectorSizeInBits / 128; + unsigned NumLaneElts = NumElts / NumLanes; + unsigned NumLaneSubElts = 64 / ScalarSizeInBits; + + for (unsigned l = 0; l < NumElts; l += NumLaneElts) + for (unsigned i = 0; i < NumLaneElts; i += NumLaneSubElts) + for (unsigned s = 0; s != NumLaneSubElts; s++) + ShuffleMask.push_back(l + s); +} + +void DecodePSLLDQMask(MVT VT, unsigned Imm, SmallVectorImpl<int> &ShuffleMask) { + unsigned VectorSizeInBits = VT.getSizeInBits(); + unsigned NumElts = VectorSizeInBits / 8; + unsigned NumLanes = VectorSizeInBits / 128; + unsigned NumLaneElts = NumElts / NumLanes; + + for (unsigned l = 0; l < NumElts; l += NumLaneElts) + for (unsigned i = 0; i < NumLaneElts; ++i) { + int M = SM_SentinelZero; + if (i >= Imm) M = i - Imm + l; + ShuffleMask.push_back(M); + } +} + +void DecodePSRLDQMask(MVT VT, unsigned Imm, SmallVectorImpl<int> &ShuffleMask) { + unsigned VectorSizeInBits = VT.getSizeInBits(); + unsigned NumElts = VectorSizeInBits / 8; + unsigned NumLanes = VectorSizeInBits / 128; + unsigned NumLaneElts = NumElts / NumLanes; + + for (unsigned l = 0; l < NumElts; l += NumLaneElts) + for (unsigned i = 0; i < NumLaneElts; ++i) { + unsigned Base = i + Imm; + int M = Base + l; + if (Base >= NumLaneElts) M = SM_SentinelZero; + ShuffleMask.push_back(M); + } +} + +void DecodePALIGNRMask(MVT VT, unsigned Imm, + SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + unsigned Offset = Imm * (VT.getVectorElementType().getSizeInBits() / 8); + + unsigned NumLanes = VT.getSizeInBits() / 128; + unsigned NumLaneElts = NumElts / NumLanes; + + for (unsigned l = 0; l != NumElts; l += NumLaneElts) { + for (unsigned i = 0; i != NumLaneElts; ++i) { + unsigned Base = i + Offset; + // if i+offset is out of this lane then we actually need the other source + if (Base >= NumLaneElts) Base += NumElts - NumLaneElts; + ShuffleMask.push_back(Base + l); + } + } +} + +/// DecodePSHUFMask - This decodes the shuffle masks for pshufd, and vpermilp*. +/// VT indicates the type of the vector allowing it to handle different +/// datatypes and vector widths. +void DecodePSHUFMask(MVT VT, unsigned Imm, SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + + unsigned NumLanes = VT.getSizeInBits() / 128; + unsigned NumLaneElts = NumElts / NumLanes; + + unsigned NewImm = Imm; + for (unsigned l = 0; l != NumElts; l += NumLaneElts) { + for (unsigned i = 0; i != NumLaneElts; ++i) { + ShuffleMask.push_back(NewImm % NumLaneElts + l); + NewImm /= NumLaneElts; + } + if (NumLaneElts == 4) NewImm = Imm; // reload imm + } +} + +void DecodePSHUFHWMask(MVT VT, unsigned Imm, + SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + + for (unsigned l = 0; l != NumElts; l += 8) { + unsigned NewImm = Imm; + for (unsigned i = 0, e = 4; i != e; ++i) { + ShuffleMask.push_back(l + i); + } + for (unsigned i = 4, e = 8; i != e; ++i) { + ShuffleMask.push_back(l + 4 + (NewImm & 3)); + NewImm >>= 2; + } + } +} + +void DecodePSHUFLWMask(MVT VT, unsigned Imm, + SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + + for (unsigned l = 0; l != NumElts; l += 8) { + unsigned NewImm = Imm; + for (unsigned i = 0, e = 4; i != e; ++i) { + ShuffleMask.push_back(l + (NewImm & 3)); + NewImm >>= 2; + } + for (unsigned i = 4, e = 8; i != e; ++i) { + ShuffleMask.push_back(l + i); + } + } +} + +/// DecodeSHUFPMask - This decodes the shuffle masks for shufp*. VT indicates +/// the type of the vector allowing it to handle different datatypes and vector +/// widths. +void DecodeSHUFPMask(MVT VT, unsigned Imm, SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + + unsigned NumLanes = VT.getSizeInBits() / 128; + unsigned NumLaneElts = NumElts / NumLanes; + + unsigned NewImm = Imm; + for (unsigned l = 0; l != NumElts; l += NumLaneElts) { + // each half of a lane comes from different source + for (unsigned s = 0; s != NumElts * 2; s += NumElts) { + for (unsigned i = 0; i != NumLaneElts / 2; ++i) { + ShuffleMask.push_back(NewImm % NumLaneElts + s + l); + NewImm /= NumLaneElts; + } + } + if (NumLaneElts == 4) NewImm = Imm; // reload imm + } +} + +/// DecodeUNPCKHMask - This decodes the shuffle masks for unpckhps/unpckhpd +/// and punpckh*. VT indicates the type of the vector allowing it to handle +/// different datatypes and vector widths. +void DecodeUNPCKHMask(MVT VT, SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + + // Handle 128 and 256-bit vector lengths. AVX defines UNPCK* to operate + // independently on 128-bit lanes. + unsigned NumLanes = VT.getSizeInBits() / 128; + if (NumLanes == 0 ) NumLanes = 1; // Handle MMX + unsigned NumLaneElts = NumElts / NumLanes; + + for (unsigned l = 0; l != NumElts; l += NumLaneElts) { + for (unsigned i = l + NumLaneElts / 2, e = l + NumLaneElts; i != e; ++i) { + ShuffleMask.push_back(i); // Reads from dest/src1 + ShuffleMask.push_back(i + NumElts); // Reads from src/src2 + } + } +} + +/// DecodeUNPCKLMask - This decodes the shuffle masks for unpcklps/unpcklpd +/// and punpckl*. VT indicates the type of the vector allowing it to handle +/// different datatypes and vector widths. +void DecodeUNPCKLMask(MVT VT, SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + + // Handle 128 and 256-bit vector lengths. AVX defines UNPCK* to operate + // independently on 128-bit lanes. + unsigned NumLanes = VT.getSizeInBits() / 128; + if (NumLanes == 0 ) NumLanes = 1; // Handle MMX + unsigned NumLaneElts = NumElts / NumLanes; + + for (unsigned l = 0; l != NumElts; l += NumLaneElts) { + for (unsigned i = l, e = l + NumLaneElts / 2; i != e; ++i) { + ShuffleMask.push_back(i); // Reads from dest/src1 + ShuffleMask.push_back(i + NumElts); // Reads from src/src2 + } + } +} + +void DecodeVPERM2X128Mask(MVT VT, unsigned Imm, + SmallVectorImpl<int> &ShuffleMask) { + if (Imm & 0x88) + return; // Not a shuffle + + unsigned HalfSize = VT.getVectorNumElements() / 2; + + for (unsigned l = 0; l != 2; ++l) { + unsigned HalfBegin = ((Imm >> (l * 4)) & 0x3) * HalfSize; + for (unsigned i = HalfBegin, e = HalfBegin + HalfSize; i != e; ++i) + ShuffleMask.push_back(i); + } +} + +void DecodePSHUFBMask(const Constant *C, SmallVectorImpl<int> &ShuffleMask) { + Type *MaskTy = C->getType(); + // It is not an error for the PSHUFB mask to not be a vector of i8 because the + // constant pool uniques constants by their bit representation. + // e.g. the following take up the same space in the constant pool: + // i128 -170141183420855150465331762880109871104 + // + // <2 x i64> <i64 -9223372034707292160, i64 -9223372034707292160> + // + // <4 x i32> <i32 -2147483648, i32 -2147483648, + // i32 -2147483648, i32 -2147483648> + + unsigned MaskTySize = MaskTy->getPrimitiveSizeInBits(); + + if (MaskTySize != 128 && MaskTySize != 256) // FIXME: Add support for AVX-512. + return; + + // This is a straightforward byte vector. + if (MaskTy->isVectorTy() && MaskTy->getVectorElementType()->isIntegerTy(8)) { + int NumElements = MaskTy->getVectorNumElements(); + ShuffleMask.reserve(NumElements); + + for (int i = 0; i < NumElements; ++i) { + // For AVX vectors with 32 bytes the base of the shuffle is the 16-byte + // lane of the vector we're inside. + int Base = i < 16 ? 0 : 16; + Constant *COp = C->getAggregateElement(i); + if (!COp) { + ShuffleMask.clear(); + return; + } else if (isa<UndefValue>(COp)) { + ShuffleMask.push_back(SM_SentinelUndef); + continue; + } + uint64_t Element = cast<ConstantInt>(COp)->getZExtValue(); + // If the high bit (7) of the byte is set, the element is zeroed. + if (Element & (1 << 7)) + ShuffleMask.push_back(SM_SentinelZero); + else { + // Only the least significant 4 bits of the byte are used. + int Index = Base + (Element & 0xf); + ShuffleMask.push_back(Index); + } + } + } + // TODO: Handle funny-looking vectors too. +} + +void DecodePSHUFBMask(ArrayRef<uint64_t> RawMask, + SmallVectorImpl<int> &ShuffleMask) { + for (int i = 0, e = RawMask.size(); i < e; ++i) { + uint64_t M = RawMask[i]; + if (M == (uint64_t)SM_SentinelUndef) { + ShuffleMask.push_back(M); + continue; + } + // For AVX vectors with 32 bytes the base of the shuffle is the half of + // the vector we're inside. + int Base = i < 16 ? 0 : 16; + // If the high bit (7) of the byte is set, the element is zeroed. + if (M & (1 << 7)) + ShuffleMask.push_back(SM_SentinelZero); + else { + // Only the least significant 4 bits of the byte are used. + int Index = Base + (M & 0xf); + ShuffleMask.push_back(Index); + } + } +} + +void DecodeBLENDMask(MVT VT, unsigned Imm, SmallVectorImpl<int> &ShuffleMask) { + int ElementBits = VT.getScalarSizeInBits(); + int NumElements = VT.getVectorNumElements(); + for (int i = 0; i < NumElements; ++i) { + // If there are more than 8 elements in the vector, then any immediate blend + // mask applies to each 128-bit lane. There can never be more than + // 8 elements in a 128-bit lane with an immediate blend. + int Bit = NumElements > 8 ? i % (128 / ElementBits) : i; + assert(Bit < 8 && + "Immediate blends only operate over 8 elements at a time!"); + ShuffleMask.push_back(((Imm >> Bit) & 1) ? NumElements + i : i); + } +} + +/// DecodeVPERMMask - this decodes the shuffle masks for VPERMQ/VPERMPD. +/// No VT provided since it only works on 256-bit, 4 element vectors. +void DecodeVPERMMask(unsigned Imm, SmallVectorImpl<int> &ShuffleMask) { + for (unsigned i = 0; i != 4; ++i) { + ShuffleMask.push_back((Imm >> (2 * i)) & 3); + } +} + +void DecodeVPERMILPMask(const Constant *C, SmallVectorImpl<int> &ShuffleMask) { + Type *MaskTy = C->getType(); + assert(MaskTy->isVectorTy() && "Expected a vector constant mask!"); + assert(MaskTy->getVectorElementType()->isIntegerTy() && + "Expected integer constant mask elements!"); + int ElementBits = MaskTy->getScalarSizeInBits(); + int NumElements = MaskTy->getVectorNumElements(); + assert((NumElements == 2 || NumElements == 4 || NumElements == 8) && + "Unexpected number of vector elements."); + ShuffleMask.reserve(NumElements); + if (auto *CDS = dyn_cast<ConstantDataSequential>(C)) { + assert((unsigned)NumElements == CDS->getNumElements() && + "Constant mask has a different number of elements!"); + + for (int i = 0; i < NumElements; ++i) { + int Base = (i * ElementBits / 128) * (128 / ElementBits); + uint64_t Element = CDS->getElementAsInteger(i); + // Only the least significant 2 bits of the integer are used. + int Index = Base + (Element & 0x3); + ShuffleMask.push_back(Index); + } + } else if (auto *CV = dyn_cast<ConstantVector>(C)) { + assert((unsigned)NumElements == C->getNumOperands() && + "Constant mask has a different number of elements!"); + + for (int i = 0; i < NumElements; ++i) { + int Base = (i * ElementBits / 128) * (128 / ElementBits); + Constant *COp = CV->getOperand(i); + if (isa<UndefValue>(COp)) { + ShuffleMask.push_back(SM_SentinelUndef); + continue; + } + uint64_t Element = cast<ConstantInt>(COp)->getZExtValue(); + // Only the least significant 2 bits of the integer are used. + int Index = Base + (Element & 0x3); + ShuffleMask.push_back(Index); + } + } +} + +void DecodeZeroExtendMask(MVT SrcVT, MVT DstVT, SmallVectorImpl<int> &Mask) { + unsigned NumDstElts = DstVT.getVectorNumElements(); + unsigned SrcScalarBits = SrcVT.getScalarSizeInBits(); + unsigned DstScalarBits = DstVT.getScalarSizeInBits(); + unsigned Scale = DstScalarBits / SrcScalarBits; + assert(SrcScalarBits < DstScalarBits && + "Expected zero extension mask to increase scalar size"); + assert(SrcVT.getVectorNumElements() >= NumDstElts && + "Too many zero extension lanes"); + + for (unsigned i = 0; i != NumDstElts; i++) { + Mask.push_back(i); + for (unsigned j = 1; j != Scale; j++) + Mask.push_back(SM_SentinelZero); + } +} + +void DecodeZeroMoveLowMask(MVT VT, SmallVectorImpl<int> &ShuffleMask) { + unsigned NumElts = VT.getVectorNumElements(); + ShuffleMask.push_back(0); + for (unsigned i = 1; i < NumElts; i++) + ShuffleMask.push_back(SM_SentinelZero); +} + +void DecodeScalarMoveMask(MVT VT, bool IsLoad, SmallVectorImpl<int> &Mask) { + // First element comes from the first element of second source. + // Remaining elements: Load zero extends / Move copies from first source. + unsigned NumElts = VT.getVectorNumElements(); + Mask.push_back(NumElts); + for (unsigned i = 1; i < NumElts; i++) + Mask.push_back(IsLoad ? static_cast<int>(SM_SentinelZero) : i); +} +} // namespace llvm |