[RISCV] Make SplatOperand start from 0.

[HanKuanChen]

Summary

Current SplatOperand starts from 1 because operand 0 (or 1) is intrinsic

id in SelectionDAG.

[craig.topper]

LGTM

llvm/include/llvm/IR/IntrinsicsRISCV.td

let TargetPrefix = "riscv" in {
   def int_riscv_crc32c_h : BitManipGPRIntrinsics;
   def int_riscv_crc32c_w : BitManipGPRIntrinsics;
   def int_riscv_crc32c_d : BitManipGPRIntrinsics;
 } // TargetPrefix = "riscv"
 
 //===----------------------------------------------------------------------===//
 // Vectors
 
+// The intrinsic does not have any operand that must be extended.
+defvar NoSplatOperand = 0xF;
+
 class RISCVVIntrinsic {
   // These intrinsics may accept illegal integer values in their llvm_any_ty
-  // operand, so they have to be extended. If set to zero then the intrinsic
-  // does not have any operand that must be extended.
+  // operand, so they have to be extended.
   Intrinsic IntrinsicID = !cast<Intrinsic>(NAME);
-  bits<4> SplatOperand = 0;
+  bits<4> SplatOperand = NoSplatOperand;
 }
 
 let TargetPrefix = "riscv" in {
   // We use anyint here but we only support XLen.
   def int_riscv_vsetvli   : Intrinsic<[llvm_anyint_ty],
                            /* AVL */  [LLVMMatchType<0>,
                            /* VSEW */  LLVMMatchType<0>,
                            /* VLMUL */ LLVMMatchType<0>],
class RISCVGatherVXMask
                    [ImmArg<ArgIndex<5>>, IntrNoMem]>, RISCVVIntrinsic {
   }
   // For destination vector type is the same as first source vector.
   // Input: (vector_in, vector_in/scalar_in, vl)
   class RISCVBinaryAAXNoMask
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, llvm_any_ty, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   // For destination vector type is the same as first source vector (with mask).
   // Input: (maskedoff, vector_in, vector_in/scalar_in, mask, vl, ta)
   class RISCVBinaryAAXMask
        : Intrinsic<[llvm_anyvector_ty],
                    [LLVMMatchType<0>, LLVMMatchType<0>, llvm_any_ty,
                     LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>, llvm_anyint_ty,
                     LLVMMatchType<2>],
                    [ImmArg<ArgIndex<5>>, IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 3;
+    let SplatOperand = 2;
   }
   // For destination vector type is the same as first source vector. The
   // second source operand must match the destination type or be an XLen scalar.
   // Input: (vector_in, vector_in/scalar_in, vl)
   class RISCVBinaryAAShiftNoMask
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, llvm_any_ty, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic;
   // For destination vector type is the same as first source vector (with mask).
   // The second source operand must match the destination type or be an XLen scalar.
   // Input: (maskedoff, vector_in, vector_in/scalar_in, mask, vl, ta)
   class RISCVBinaryAAShiftMask
        : Intrinsic<[llvm_anyvector_ty],
                    [LLVMMatchType<0>, LLVMMatchType<0>, llvm_any_ty,
                     LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>, llvm_anyint_ty,
                     LLVMMatchType<2>],
                    [ImmArg<ArgIndex<5>>, IntrNoMem]>, RISCVVIntrinsic;
   // For destination vector type is NOT the same as first source vector.
   // Input: (vector_in, vector_in/scalar_in, vl)
   class RISCVBinaryABXNoMask
         : Intrinsic<[llvm_anyvector_ty],
                     [llvm_anyvector_ty, llvm_any_ty, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   // For destination vector type is NOT the same as first source vector (with mask).
   // Input: (maskedoff, vector_in, vector_in/scalar_in, mask, vl, ta)
   class RISCVBinaryABXMask
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, llvm_anyvector_ty, llvm_any_ty,
                      LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>, llvm_anyint_ty,
                      LLVMMatchType<3>],
                     [ImmArg<ArgIndex<5>>, IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 3;
+    let SplatOperand = 2;
   }
   // For destination vector type is NOT the same as first source vector. The
   // second source operand must match the destination type or be an XLen scalar.
   // Input: (vector_in, vector_in/scalar_in, vl)
   class RISCVBinaryABShiftNoMask
         : Intrinsic<[llvm_anyvector_ty],
                     [llvm_anyvector_ty, llvm_any_ty, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic;
let TargetPrefix = "riscv" in {
   // For binary operations with V0 as input.
   // Input: (vector_in, vector_in/scalar_in, V0, vl)
   class RISCVBinaryWithV0
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, llvm_any_ty,
                      LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>,
                      llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   // For binary operations with mask type output and V0 as input.
   // Output: (mask type output)
   // Input: (vector_in, vector_in/scalar_in, V0, vl)
   class RISCVBinaryMOutWithV0
         :Intrinsic<[LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>],
                    [llvm_anyvector_ty, llvm_any_ty,
                     LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>,
                     llvm_anyint_ty],
                    [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   // For binary operations with mask type output.
   // Output: (mask type output)
   // Input: (vector_in, vector_in/scalar_in, vl)
   class RISCVBinaryMOut
         : Intrinsic<[LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>],
                     [llvm_anyvector_ty, llvm_any_ty, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   // For binary operations with mask type output without mask.
   // Output: (mask type output)
   // Input: (vector_in, vector_in/scalar_in, vl)
   class RISCVCompareNoMask
         : Intrinsic<[LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>],
                     [llvm_anyvector_ty, llvm_any_ty, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   // For binary operations with mask type output with mask.
   // Output: (mask type output)
   // Input: (maskedoff, vector_in, vector_in/scalar_in, mask, vl)
   class RISCVCompareMask
         : Intrinsic<[LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>],
                     [LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>,
                      llvm_anyvector_ty, llvm_any_ty,
                      LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 3;
+    let SplatOperand = 2;
   }
   // For FP classify operations.
   // Output: (bit mask type output)
   // Input: (vector_in, vl)
   class RISCVClassifyNoMask
         : Intrinsic<[LLVMVectorOfBitcastsToInt<0>],
                     [llvm_anyvector_ty, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic;
   // For FP classify operations with mask.
   // Output: (bit mask type output)
   // Input: (maskedoff, vector_in, mask, vl)
   class RISCVClassifyMask
         : Intrinsic<[LLVMVectorOfBitcastsToInt<0>],
                     [LLVMVectorOfBitcastsToInt<0>, llvm_anyvector_ty,
                      LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic;
   // For Saturating binary operations.
   // The destination vector type is the same as first source vector.
   // Input: (vector_in, vector_in/scalar_in, vl)
   class RISCVSaturatingBinaryAAXNoMask
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, llvm_any_ty, llvm_anyint_ty],
                     [IntrNoMem, IntrHasSideEffects]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   // For Saturating binary operations with mask.
   // The destination vector type is the same as first source vector.
   // Input: (maskedoff, vector_in, vector_in/scalar_in, mask, vl, ta)
   class RISCVSaturatingBinaryAAXMask
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, LLVMMatchType<0>, llvm_any_ty,
                      LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>, llvm_anyint_ty,
                      LLVMMatchType<2>],
                     [ImmArg<ArgIndex<5>>, IntrNoMem, IntrHasSideEffects]>, RISCVVIntrinsic {
-    let SplatOperand = 3;
+    let SplatOperand = 2;
   }
   // For Saturating binary operations.
   // The destination vector type is the same as first source vector.
   // The second source operand matches the destination type or is an XLen scalar.
   // Input: (vector_in, vector_in/scalar_in, vl)
   class RISCVSaturatingBinaryAAShiftNoMask
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, llvm_any_ty, llvm_anyint_ty],
class RISCVTernaryAAAXMask
                     [LLVMMatchType<0>, LLVMMatchType<0>, llvm_anyint_ty,
                      LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>, LLVMMatchType<1>],
                     [IntrNoMem]>, RISCVVIntrinsic;
   class RISCVTernaryAAXANoMask
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, llvm_any_ty, LLVMMatchType<0>,
                      llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   class RISCVTernaryAAXAMask
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, llvm_any_ty, LLVMMatchType<0>,
                      LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>, llvm_anyint_ty],
                     [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   class RISCVTernaryWideNoMask
         : Intrinsic< [llvm_anyvector_ty],
                      [LLVMMatchType<0>, llvm_any_ty, llvm_anyvector_ty,
                       llvm_anyint_ty],
                      [IntrNoMem] >, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   class RISCVTernaryWideMask
         : Intrinsic< [llvm_anyvector_ty],
                      [LLVMMatchType<0>, llvm_any_ty, llvm_anyvector_ty,
                       LLVMScalarOrSameVectorWidth<0, llvm_i1_ty>, llvm_anyint_ty],
                      [IntrNoMem]>, RISCVVIntrinsic {
-    let SplatOperand = 2;
+    let SplatOperand = 1;
   }
   // For Reduction ternary operations.
   // For destination vector type is the same as first and third source vector.
   // Input: (vector_in, vector_in, vector_in, vl)
   class RISCVReductionNoMask
         : Intrinsic<[llvm_anyvector_ty],
                     [LLVMMatchType<0>, llvm_anyvector_ty, LLVMMatchType<0>,
                      llvm_anyint_ty],

llvm/lib/Target/RISCV/RISCVISelLowering.h

 static constexpr unsigned RVVBitsPerBlock = 64;
 } // namespace RISCV
 
 namespace RISCVVIntrinsicsTable {
 
 struct RISCVVIntrinsicInfo {
   unsigned IntrinsicID;
   uint8_t SplatOperand;
+  bool hasSplatOperand() const {
+    // 0xF is not valid. See NoSplatOperand in IntrinsicsRISCV.td.
+    return SplatOperand != 0xF;
+  }
 };
 
 using namespace RISCV;
 
 #define GET_RISCVVIntrinsicsTable_DECL
 #include "RISCVGenSearchableTables.inc"
 
 } // end namespace RISCVVIntrinsicsTable
 
 } // end namespace llvm
 
 #endif

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

if (!Subtarget.hasVInstructions())
     return SDValue();
 
   bool HasChain = Op.getOpcode() == ISD::INTRINSIC_W_CHAIN;
   unsigned IntNo = Op.getConstantOperandVal(HasChain ? 1 : 0);
   SDLoc DL(Op);
 
   const RISCVVIntrinsicsTable::RISCVVIntrinsicInfo *II =
       RISCVVIntrinsicsTable::getRISCVVIntrinsicInfo(IntNo);
-  if (!II || !II->SplatOperand)
+  if (!II || !II->hasSplatOperand())
     return SDValue();
 
-  unsigned SplatOp = II->SplatOperand + HasChain;
+  unsigned SplatOp = II->SplatOperand + 1 + HasChain;
   assert(SplatOp < Op.getNumOperands());
 
   SmallVector<SDValue, 8> Operands(Op->op_begin(), Op->op_end());
   SDValue &ScalarOp = Operands[SplatOp];
   MVT OpVT = ScalarOp.getSimpleValueType();
   MVT XLenVT = Subtarget.getXLenVT();
 
   // If this isn't a scalar, or its type is XLenVT we're done.
static SDValue lowerVectorIntrinsicSplats(SDValue Op, SelectionDAG &DAG,
   }
 
   // Use the previous operand to get the vXi64 VT. The result might be a mask
   // VT for compares. Using the previous operand assumes that the previous
   // operand will never have a smaller element size than a scalar operand and
   // that a widening operation never uses SEW=64.
   // NOTE: If this fails the below assert, we can probably just find the
   // element count from any operand or result and use it to construct the VT.
-  assert(II->SplatOperand > 1 && "Unexpected splat operand!");
+  assert(II->SplatOperand > 0 && "Unexpected splat operand!");
   MVT VT = Op.getOperand(SplatOp - 1).getSimpleValueType();
 
   // The more complex case is when the scalar is larger than XLenVT.
   assert(XLenVT == MVT::i32 && OpVT == MVT::i64 &&
          VT.getVectorElementType() == MVT::i64 && "Unexpected VTs!");
 
   // If this is a sign-extended 32-bit constant, we can truncate it and rely
   // on the instruction to sign-extend since SEW>XLEN.