[SVE][TableGen] Vector element constraint

[huntergr]

Summary

Adds a new tablegen constraint to match a scalar type against the
element type of a vector.

I'll link to the patch that uses it once uploaded.

[huntergr]

This comment was removed by huntergr.

[fhahn]

Is this still needed? Marking as changes requested to clear from review queue.

[huntergr]

Very much outdated.

include/llvm/IR/Intrinsics.h

#undef GET_INTRINSIC_ENUM_VALUES
 
   /// This is a type descriptor which explains the type requirements of an
   /// intrinsic. This is returned by getIntrinsicInfoTableEntries.
   struct IITDescriptor {
     enum IITDescriptorKind {
       Void, VarArg, MMX, Token, Metadata, Half, Float, Double,
       Integer, Vector, Pointer, Struct,
       Argument, ExtendArgument, TruncArgument, HalfVecArgument,
-      SameVecWidthArgument, PtrToArgument, PtrToElt, VecOfAnyPtrsToElt
+      SameVecWidthArgument, PtrToArgument, PtrToElt, VecOfAnyPtrsToElt,
+      VecElementArgument
     } Kind;
 
     union {
       unsigned Integer_Width;
       unsigned Float_Width;
       unsigned Vector_Width;
       unsigned Pointer_AddressSpace;
       unsigned Struct_NumElements;
       unsigned Argument_Info;
     };
 
     enum ArgKind {
       AK_Any,
       AK_AnyInteger,
       AK_AnyFloat,
       AK_AnyVector,
       AK_AnyPointer
     };
 
     unsigned getArgumentNumber() const {
       assert(Kind == Argument || Kind == ExtendArgument ||
              Kind == TruncArgument || Kind == HalfVecArgument ||
              Kind == SameVecWidthArgument || Kind == PtrToArgument ||
-             Kind == PtrToElt);
+             Kind == PtrToElt || Kind == VecElementArgument);
       return Argument_Info >> 3;
     }
     ArgKind getArgumentKind() const {
       assert(Kind == Argument || Kind == ExtendArgument ||
              Kind == TruncArgument || Kind == HalfVecArgument ||
-             Kind == SameVecWidthArgument || Kind == PtrToArgument);
+             Kind == SameVecWidthArgument || Kind == PtrToArgument ||
+             Kind == VecElementArgument);
       return (ArgKind)(Argument_Info & 7);
     }
 
     // VecOfAnyPtrsToElt uses both an overloaded argument (for address space)
     // and a reference argument (for matching vector width and element types)
     unsigned getOverloadArgNumber() const {
       assert(Kind == VecOfAnyPtrsToElt);
       return Argument_Info >> 16;

include/llvm/IR/Intrinsics.td

 class LLVMTruncatedType<int num> : LLVMMatchType<num>;
 class LLVMVectorSameWidth<int num, LLVMType elty>
   : LLVMMatchType<num> {
   ValueType ElTy = elty.VT;
 }
 class LLVMPointerTo<int num> : LLVMMatchType<num>;
 class LLVMPointerToElt<int num> : LLVMMatchType<num>;
 class LLVMVectorOfAnyPointersToElt<int num> : LLVMMatchType<num>;
+class LLVMVectorElementType<int num> : LLVMMatchType<num>;
 
 // Match the type of another intrinsic parameter that is expected to be a
 // vector type, but change the element count to be half as many
 class LLVMHalfElementsVectorType<int num> : LLVMMatchType<num>;
 
 def llvm_void_ty       : LLVMType<isVoid>;
 let isAny = 1 in {
   def llvm_any_ty        : LLVMType<Any>;

lib/IR/Function.cpp

enum IIT_Info {
   IIT_PTR_TO_ARG = 32,
   IIT_PTR_TO_ELT = 33,
   IIT_VEC_OF_ANYPTRS_TO_ELT = 34,
   IIT_I128 = 35,
   IIT_V512 = 36,
   IIT_V1024 = 37,
   IIT_STRUCT6 = 38,
   IIT_STRUCT7 = 39,
-  IIT_STRUCT8 = 40
+  IIT_STRUCT8 = 40,
+  IIT_VEC_ELEMENT = 41
 };
 
 static void DecodeIITType(unsigned &NextElt, ArrayRef<unsigned char> Infos,
                       SmallVectorImpl<Intrinsic::IITDescriptor> &OutputTable) {
   using namespace Intrinsic;
 
   IIT_Info Info = IIT_Info(Infos[NextElt++]);
   unsigned StructElts = 2;
static void DecodeIITType(unsigned &NextElt, ArrayRef<unsigned char> Infos,
   case IIT_STRUCT3: ++StructElts; LLVM_FALLTHROUGH;
   case IIT_STRUCT2: {
     OutputTable.push_back(IITDescriptor::get(IITDescriptor::Struct,StructElts));
 
     for (unsigned i = 0; i != StructElts; ++i)
       DecodeIITType(NextElt, Infos, OutputTable);
     return;
   }
+  case IIT_VEC_ELEMENT: {
+    unsigned ArgInfo = (NextElt == Infos.size() ? 0 : Infos[NextElt++]);
+    OutputTable.push_back(IITDescriptor::get(IITDescriptor::VecElementArgument,
+                                             ArgInfo));
+    return;
+  }
   }
   llvm_unreachable("unhandled");
 }
 
 #define GET_INTRINSIC_GENERATOR_GLOBAL
 #include "llvm/IR/Intrinsics.inc"
 #undef GET_INTRINSIC_GENERATOR_GLOBAL
 
case IITDescriptor::PtrToElt: {
     if (!VTy)
       llvm_unreachable("Expected an argument of Vector Type");
     Type *EltTy = VTy->getVectorElementType();
     return PointerType::getUnqual(EltTy);
   }
   case IITDescriptor::VecOfAnyPtrsToElt:
     // Return the overloaded type (which determines the pointers address space)
     return Tys[D.getOverloadArgNumber()];
+  case IITDescriptor::VecElementArgument: {
+    Type *Ty = Tys[D.getArgumentNumber()];
+    if (VectorType *VTy = dyn_cast<VectorType>(Ty))
+      return VTy->getElementType();
+    llvm_unreachable("Expected an argument of Vector Type");
+  }
   }
   llvm_unreachable("unhandled");
 }
 
 FunctionType *Intrinsic::getType(LLVMContext &Context,
                                  ID id, ArrayRef<Type*> Tys) {
   SmallVector<IITDescriptor, 8> Table;
   getIntrinsicInfoTableEntries(id, Table);
case IITDescriptor::VecOfAnyPtrsToElt: {
         return true;
       PointerType *ThisArgEltTy =
               dyn_cast<PointerType>(ThisArgVecTy->getVectorElementType());
       if (!ThisArgEltTy)
         return true;
       return ThisArgEltTy->getElementType() !=
              ReferenceType->getVectorElementType();
     }
+    case IITDescriptor::VecElementArgument: {
+      if (D.getArgumentNumber() >= ArgTys.size())
+        return true;
+      auto *ReferenceType = dyn_cast<VectorType>(ArgTys[D.getArgumentNumber()]);
+      return !ReferenceType || Ty != ReferenceType->getElementType();
+    }
   }
   llvm_unreachable("unhandled");
 }
 
 bool
 Intrinsic::matchIntrinsicVarArg(bool isVarArg,
                                 ArrayRef<Intrinsic::IITDescriptor> &Infos) {
   // If there are no descriptors left, then it can't be a vararg.

utils/TableGen/IntrinsicEmitter.cpp

enum IIT_Info {
   IIT_PTR_TO_ARG = 32,
   IIT_PTR_TO_ELT = 33,
   IIT_VEC_OF_ANYPTRS_TO_ELT = 34,
   IIT_I128 = 35,
   IIT_V512 = 36,
   IIT_V1024 = 37,
   IIT_STRUCT6 = 38,
   IIT_STRUCT7 = 39,
-  IIT_STRUCT8 = 40
+  IIT_STRUCT8 = 40,
+  IIT_VEC_ELEMENT = 41
 };
 
 static void EncodeFixedValueType(MVT::SimpleValueType VT,
                                  std::vector<unsigned char> &Sig) {
   if (MVT(VT).isInteger()) {
     unsigned BitWidth = MVT(VT).getSizeInBits();
     switch (BitWidth) {
     default: PrintFatalError("unhandled integer type width in intrinsic!");
else if (R->isSubClassOf("LLVMVectorOfAnyPointersToElt")) {
       ArgCodes.push_back(3 /*vAny*/);
       // Encode overloaded ArgNo
       Sig.push_back(ArgNo);
       // Encode LLVMMatchType<Number> ArgNo
       Sig.push_back(Number);
       return;
     } else if (R->isSubClassOf("LLVMPointerToElt"))
       Sig.push_back(IIT_PTR_TO_ELT);
+    else if (R->isSubClassOf("LLVMVectorElementType"))
+      Sig.push_back(IIT_VEC_ELEMENT);
     else
       Sig.push_back(IIT_ARG);
     return Sig.push_back((Number << 3) | ArgCodes[Number]);
   }
 
   MVT::SimpleValueType VT = getValueType(R->getValueAsDef("VT"));
 
   unsigned Tmp = 0;