+/// Attempt to simplify SSE4A EXTRQ/EXTRQI instructions using constant folding
+/// or conversion to a shuffle vector.
+static Value *SimplifyX86extrq(IntrinsicInst &II, Value *Op0,
+ ConstantInt *CILength, ConstantInt *CIIndex,
+ InstCombiner::BuilderTy &Builder) {
+ auto LowConstantHighUndef = [&](uint64_t Val) {
+ Type *IntTy64 = Type::getInt64Ty(II.getContext());
+ Constant *Args[] = {ConstantInt::get(IntTy64, Val),
+ UndefValue::get(IntTy64)};
+ return ConstantVector::get(Args);
+ };
+
+ // See if we're dealing with constant values.
+ Constant *C0 = dyn_cast<Constant>(Op0);
+ ConstantInt *CI0 =
+ C0 ? dyn_cast<ConstantInt>(C0->getAggregateElement((unsigned)0))
+ : nullptr;
+
+ // Attempt to constant fold.
+ if (CILength && CIIndex) {
+ // From AMD documentation: "The bit index and field length are each six
+ // bits in length other bits of the field are ignored."
+ APInt APIndex = CIIndex->getValue().zextOrTrunc(6);
+ APInt APLength = CILength->getValue().zextOrTrunc(6);
+
+ unsigned Index = APIndex.getZExtValue();
+
+ // From AMD documentation: "a value of zero in the field length is
+ // defined as length of 64".
+ unsigned Length = APLength == 0 ? 64 : APLength.getZExtValue();
+
+ // From AMD documentation: "If the sum of the bit index + length field
+ // is greater than 64, the results are undefined".
+ unsigned End = Index + Length;
+
+ // Note that both field index and field length are 8-bit quantities.
+ // Since variables 'Index' and 'Length' are unsigned values
+ // obtained from zero-extending field index and field length
+ // respectively, their sum should never wrap around.
+ if (End > 64)
+ return UndefValue::get(II.getType());
+
+ // If we are inserting whole bytes, we can convert this to a shuffle.
+ // Lowering can recognize EXTRQI shuffle masks.
+ if ((Length % 8) == 0 && (Index % 8) == 0) {
+ // Convert bit indices to byte indices.
+ Length /= 8;
+ Index /= 8;
+
+ Type *IntTy8 = Type::getInt8Ty(II.getContext());
+ Type *IntTy32 = Type::getInt32Ty(II.getContext());
+ VectorType *ShufTy = VectorType::get(IntTy8, 16);
+
+ SmallVector<Constant *, 16> ShuffleMask;
+ for (int i = 0; i != (int)Length; ++i)
+ ShuffleMask.push_back(
+ Constant::getIntegerValue(IntTy32, APInt(32, i + Index)));
+ for (int i = Length; i != 8; ++i)
+ ShuffleMask.push_back(
+ Constant::getIntegerValue(IntTy32, APInt(32, i + 16)));
+ for (int i = 8; i != 16; ++i)
+ ShuffleMask.push_back(UndefValue::get(IntTy32));
+
+ Value *SV = Builder.CreateShuffleVector(
+ Builder.CreateBitCast(Op0, ShufTy),
+ ConstantAggregateZero::get(ShufTy), ConstantVector::get(ShuffleMask));
+ return Builder.CreateBitCast(SV, II.getType());
+ }
+
+ // Constant Fold - shift Index'th bit to lowest position and mask off
+ // Length bits.
+ if (CI0) {
+ APInt Elt = CI0->getValue();
+ Elt = Elt.lshr(Index).zextOrTrunc(Length);
+ return LowConstantHighUndef(Elt.getZExtValue());
+ }
+
+ // If we were an EXTRQ call, we'll save registers if we convert to EXTRQI.
+ if (II.getIntrinsicID() == Intrinsic::x86_sse4a_extrq) {
+ Value *Args[] = {Op0, CILength, CIIndex};
+ Module *M = II.getParent()->getParent()->getParent();
+ Value *F = Intrinsic::getDeclaration(M, Intrinsic::x86_sse4a_extrqi);
+ return Builder.CreateCall(F, Args);
+ }
+ }
+
+ // Constant Fold - extraction from zero is always {zero, undef}.
+ if (CI0 && CI0->equalsInt(0))
+ return LowConstantHighUndef(0);
+
+ return nullptr;
+}
+
+/// Attempt to simplify SSE4A INSERTQ/INSERTQI instructions using constant
+/// folding or conversion to a shuffle vector.
+static Value *SimplifyX86insertq(IntrinsicInst &II, Value *Op0, Value *Op1,
+ APInt APLength, APInt APIndex,
+ InstCombiner::BuilderTy &Builder) {
+
+ // From AMD documentation: "The bit index and field length are each six bits
+ // in length other bits of the field are ignored."
+ APIndex = APIndex.zextOrTrunc(6);
+ APLength = APLength.zextOrTrunc(6);
+
+ // Attempt to constant fold.
+ unsigned Index = APIndex.getZExtValue();
+
+ // From AMD documentation: "a value of zero in the field length is
+ // defined as length of 64".
+ unsigned Length = APLength == 0 ? 64 : APLength.getZExtValue();
+
+ // From AMD documentation: "If the sum of the bit index + length field
+ // is greater than 64, the results are undefined".
+ unsigned End = Index + Length;
+
+ // Note that both field index and field length are 8-bit quantities.
+ // Since variables 'Index' and 'Length' are unsigned values
+ // obtained from zero-extending field index and field length
+ // respectively, their sum should never wrap around.
+ if (End > 64)
+ return UndefValue::get(II.getType());
+
+ // If we are inserting whole bytes, we can convert this to a shuffle.
+ // Lowering can recognize INSERTQI shuffle masks.
+ if ((Length % 8) == 0 && (Index % 8) == 0) {
+ // Convert bit indices to byte indices.
+ Length /= 8;
+ Index /= 8;
+
+ Type *IntTy8 = Type::getInt8Ty(II.getContext());
+ Type *IntTy32 = Type::getInt32Ty(II.getContext());
+ VectorType *ShufTy = VectorType::get(IntTy8, 16);
+
+ SmallVector<Constant *, 16> ShuffleMask;
+ for (int i = 0; i != (int)Index; ++i)
+ ShuffleMask.push_back(Constant::getIntegerValue(IntTy32, APInt(32, i)));
+ for (int i = 0; i != (int)Length; ++i)
+ ShuffleMask.push_back(
+ Constant::getIntegerValue(IntTy32, APInt(32, i + 16)));
+ for (int i = Index + Length; i != 8; ++i)
+ ShuffleMask.push_back(Constant::getIntegerValue(IntTy32, APInt(32, i)));
+ for (int i = 8; i != 16; ++i)
+ ShuffleMask.push_back(UndefValue::get(IntTy32));
+
+ Value *SV = Builder.CreateShuffleVector(Builder.CreateBitCast(Op0, ShufTy),
+ Builder.CreateBitCast(Op1, ShufTy),
+ ConstantVector::get(ShuffleMask));
+ return Builder.CreateBitCast(SV, II.getType());
+ }
+
+ // See if we're dealing with constant values.
+ Constant *C0 = dyn_cast<Constant>(Op0);
+ Constant *C1 = dyn_cast<Constant>(Op1);
+ ConstantInt *CI00 =
+ C0 ? dyn_cast<ConstantInt>(C0->getAggregateElement((unsigned)0))
+ : nullptr;
+ ConstantInt *CI10 =
+ C1 ? dyn_cast<ConstantInt>(C1->getAggregateElement((unsigned)0))
+ : nullptr;
+
+ // Constant Fold - insert bottom Length bits starting at the Index'th bit.
+ if (CI00 && CI10) {
+ APInt V00 = CI00->getValue();
+ APInt V10 = CI10->getValue();
+ APInt Mask = APInt::getLowBitsSet(64, Length).shl(Index);
+ V00 = V00 & ~Mask;
+ V10 = V10.zextOrTrunc(Length).zextOrTrunc(64).shl(Index);
+ APInt Val = V00 | V10;
+ Type *IntTy64 = Type::getInt64Ty(II.getContext());
+ Constant *Args[] = {ConstantInt::get(IntTy64, Val.getZExtValue()),
+ UndefValue::get(IntTy64)};
+ return ConstantVector::get(Args);
+ }
+
+ // If we were an INSERTQ call, we'll save demanded elements if we convert to
+ // INSERTQI.
+ if (II.getIntrinsicID() == Intrinsic::x86_sse4a_insertq) {
+ Type *IntTy8 = Type::getInt8Ty(II.getContext());
+ Constant *CILength = ConstantInt::get(IntTy8, Length, false);
+ Constant *CIIndex = ConstantInt::get(IntTy8, Index, false);
+
+ Value *Args[] = {Op0, Op1, CILength, CIIndex};
+ Module *M = II.getParent()->getParent()->getParent();
+ Value *F = Intrinsic::getDeclaration(M, Intrinsic::x86_sse4a_insertqi);
+ return Builder.CreateCall(F, Args);
+ }
+
+ return nullptr;
+}
+