[AArch64][SVE] Add fixed length codegen for FP_TO_{S,U}INT/{S,U}INT_TO_FP

Depends on D102607

Differential Revision: https://reviews.llvm.org/D102777

Author: brads55

llvm/lib/Target/AArch64/AArch64ISelLowering.cpp

@@ -1482,6 +1482,8 @@ void AArch64TargetLowering::addTypeForFixedLengthSVE(MVT VT) {
   setOperationAction(ISD::FNEG, VT, Custom);
   setOperationAction(ISD::FP_EXTEND, VT, Custom);
   setOperationAction(ISD::FP_ROUND, VT, Custom);
+  setOperationAction(ISD::FP_TO_SINT, VT, Custom);
+  setOperationAction(ISD::FP_TO_UINT, VT, Custom);
   setOperationAction(ISD::FRINT, VT, Custom);
   setOperationAction(ISD::FROUND, VT, Custom);
   setOperationAction(ISD::FROUNDEVEN, VT, Custom);
@@ -1501,6 +1503,7 @@ void AArch64TargetLowering::addTypeForFixedLengthSVE(MVT VT) {
   setOperationAction(ISD::SHL, VT, Custom);
   setOperationAction(ISD::SIGN_EXTEND, VT, Custom);
   setOperationAction(ISD::SIGN_EXTEND_INREG, VT, Custom);
+  setOperationAction(ISD::SINT_TO_FP, VT, Custom);
   setOperationAction(ISD::SMAX, VT, Custom);
   setOperationAction(ISD::SMIN, VT, Custom);
   setOperationAction(ISD::SPLAT_VECTOR, VT, Custom);
@@ -1510,6 +1513,7 @@ void AArch64TargetLowering::addTypeForFixedLengthSVE(MVT VT) {
   setOperationAction(ISD::SUB, VT, Custom);
   setOperationAction(ISD::TRUNCATE, VT, Custom);
   setOperationAction(ISD::UDIV, VT, Custom);
+  setOperationAction(ISD::UINT_TO_FP, VT, Custom);
   setOperationAction(ISD::UMAX, VT, Custom);
   setOperationAction(ISD::UMIN, VT, Custom);
   setOperationAction(ISD::VECREDUCE_ADD, VT, Custom);
@@ -3260,6 +3264,9 @@ SDValue AArch64TargetLowering::LowerVectorFP_TO_INT(SDValue Op,
     return LowerToPredicatedOp(Op, DAG, Opcode);
   }
 
+  if (useSVEForFixedLengthVectorVT(VT) || useSVEForFixedLengthVectorVT(InVT))
+    return LowerFixedLengthFPToIntToSVE(Op, DAG);
+
   unsigned NumElts = InVT.getVectorNumElements();
 
   // f16 conversions are promoted to f32 when full fp16 is not supported.
@@ -3384,6 +3391,9 @@ SDValue AArch64TargetLowering::LowerVectorINT_TO_FP(SDValue Op,
     return LowerToPredicatedOp(Op, DAG, Opcode);
   }
 
+  if (useSVEForFixedLengthVectorVT(VT) || useSVEForFixedLengthVectorVT(InVT))
+    return LowerFixedLengthIntToFPToSVE(Op, DAG);
+
   uint64_t VTSize = VT.getFixedSizeInBits();
   uint64_t InVTSize = InVT.getFixedSizeInBits();
   if (VTSize < InVTSize) {
@@ -17994,6 +18004,95 @@ AArch64TargetLowering::LowerFixedLengthFPRoundToSVE(SDValue Op,
   return DAG.getNode(ISD::BITCAST, DL, VT, Val);
 }
 
+SDValue
+AArch64TargetLowering::LowerFixedLengthIntToFPToSVE(SDValue Op,
+                                                    SelectionDAG &DAG) const {
+  EVT VT = Op.getValueType();
+  assert(VT.isFixedLengthVector() && "Expected fixed length vector type!");
+
+  bool IsSigned = Op.getOpcode() == ISD::SINT_TO_FP;
+  unsigned Opcode = IsSigned ? AArch64ISD::SINT_TO_FP_MERGE_PASSTHRU
+                             : AArch64ISD::UINT_TO_FP_MERGE_PASSTHRU;
+
+  SDLoc DL(Op);
+  SDValue Val = Op.getOperand(0);
+  EVT SrcVT = Val.getValueType();
+  EVT ContainerDstVT = getContainerForFixedLengthVector(DAG, VT);
+  EVT ContainerSrcVT = getContainerForFixedLengthVector(DAG, SrcVT);
+
+  if (ContainerSrcVT.getVectorElementType().getSizeInBits() <=
+      ContainerDstVT.getVectorElementType().getSizeInBits()) {
+    SDValue Pg = getPredicateForVector(DAG, DL, VT);
+
+    Val = DAG.getNode(IsSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND, DL,
+                      VT.changeTypeToInteger(), Val);
+
+    Val = convertToScalableVector(DAG, ContainerSrcVT, Val);
+    Val = getSVESafeBitCast(ContainerDstVT.changeTypeToInteger(), Val, DAG);
+    // Safe to use a larger than specified operand since we just unpacked the
+    // data, hence the upper bits are zero.
+    Val = DAG.getNode(Opcode, DL, ContainerDstVT, Pg, Val,
+                      DAG.getUNDEF(ContainerDstVT));
+    return convertFromScalableVector(DAG, VT, Val);
+  } else {
+    EVT CvtVT = ContainerSrcVT.changeVectorElementType(
+        ContainerDstVT.getVectorElementType());
+    SDValue Pg = getPredicateForVector(DAG, DL, CvtVT);
+
+    Val = convertToScalableVector(DAG, ContainerSrcVT, Val);
+    Val = DAG.getNode(Opcode, DL, CvtVT, Pg, Val, DAG.getUNDEF(CvtVT));
+    Val = getSVESafeBitCast(ContainerSrcVT, Val, DAG);
+    Val = convertFromScalableVector(DAG, SrcVT, Val);
+
+    Val = DAG.getNode(ISD::TRUNCATE, DL, VT.changeTypeToInteger(), Val);
+    return DAG.getNode(ISD::BITCAST, DL, VT, Val);
+  }
+}
+
+SDValue
+AArch64TargetLowering::LowerFixedLengthFPToIntToSVE(SDValue Op,
+                                                    SelectionDAG &DAG) const {
+  EVT VT = Op.getValueType();
+  assert(VT.isFixedLengthVector() && "Expected fixed length vector type!");
+
+  bool IsSigned = Op.getOpcode() == ISD::FP_TO_SINT;
+  unsigned Opcode = IsSigned ? AArch64ISD::FCVTZS_MERGE_PASSTHRU
+                             : AArch64ISD::FCVTZU_MERGE_PASSTHRU;
+
+  SDLoc DL(Op);
+  SDValue Val = Op.getOperand(0);
+  EVT SrcVT = Val.getValueType();
+  EVT ContainerDstVT = getContainerForFixedLengthVector(DAG, VT);
+  EVT ContainerSrcVT = getContainerForFixedLengthVector(DAG, SrcVT);
+
+  if (ContainerSrcVT.getVectorElementType().getSizeInBits() <=
+      ContainerDstVT.getVectorElementType().getSizeInBits()) {
+    EVT CvtVT = ContainerDstVT.changeVectorElementType(
+      ContainerSrcVT.getVectorElementType());
+    SDValue Pg = getPredicateForVector(DAG, DL, VT);
+
+    Val = DAG.getNode(ISD::BITCAST, DL, SrcVT.changeTypeToInteger(), Val);
+    Val = DAG.getNode(ISD::ANY_EXTEND, DL, VT, Val);
+
+    Val = convertToScalableVector(DAG, ContainerSrcVT, Val);
+    Val = getSVESafeBitCast(CvtVT, Val, DAG);
+    Val = DAG.getNode(Opcode, DL, ContainerDstVT, Pg, Val,
+                      DAG.getUNDEF(ContainerDstVT));
+    return convertFromScalableVector(DAG, VT, Val);
+  } else {
+    EVT CvtVT = ContainerSrcVT.changeTypeToInteger();
+    SDValue Pg = getPredicateForVector(DAG, DL, CvtVT);
+
+    // Safe to use a larger than specified result since an fp_to_int where the
+    // result doesn't fit into the destination is undefined.
+    Val = convertToScalableVector(DAG, ContainerSrcVT, Val);
+    Val = DAG.getNode(Opcode, DL, CvtVT, Pg, Val, DAG.getUNDEF(CvtVT));
+    Val = convertFromScalableVector(DAG, SrcVT.changeTypeToInteger(), Val);
+
+    return DAG.getNode(ISD::TRUNCATE, DL, VT, Val);
+  }
+}
+
 SDValue AArch64TargetLowering::getSVESafeBitCast(EVT VT, SDValue Op,
                                                  SelectionDAG &DAG) const {
   SDLoc DL(Op);

llvm/lib/Target/AArch64/AArch64ISelLowering.h

@@ -1005,6 +1005,8 @@ class AArch64TargetLowering : public TargetLowering {
                                              SelectionDAG &DAG) const;
   SDValue LowerFixedLengthFPExtendToSVE(SDValue Op, SelectionDAG &DAG) const;
   SDValue LowerFixedLengthFPRoundToSVE(SDValue Op, SelectionDAG &DAG) const;
+  SDValue LowerFixedLengthIntToFPToSVE(SDValue Op, SelectionDAG &DAG) const;
+  SDValue LowerFixedLengthFPToIntToSVE(SDValue Op, SelectionDAG &DAG) const;
 
   SDValue BuildSDIVPow2(SDNode *N, const APInt &Divisor, SelectionDAG &DAG,
                         SmallVectorImpl<SDNode *> &Created) const override;