[NFC] Use default case in EVT::getEVTString

[c-rhodes]

Summary

The default case handles the majority of MVTs so most of the individual
cases can be removed. Also added a case for floating point types.

[sdesmalen]

Seems like a sensible change to me.

llvm/lib/CodeGen/ValueTypes.cpp

 std::string EVT::getEVTString() const {
   switch (V.SimpleTy) {
   default:
     if (isVector())
       return (isScalableVector() ? "nxv" : "v") + utostr(getVectorNumElements())
              + getVectorElementType().getEVTString();
     if (isInteger())
       return "i" + utostr(getSizeInBits());
+    if (isFloatingPoint())
+      return "f" + utostr(getSizeInBits());
     llvm_unreachable("Invalid EVT!");
-  case MVT::i1:      return "i1";
-  case MVT::i8:      return "i8";
-  case MVT::i16:     return "i16";
-  case MVT::i32:     return "i32";
-  case MVT::i64:     return "i64";
-  case MVT::i128:    return "i128";
-  case MVT::f16:     return "f16";
-  case MVT::f32:     return "f32";
-  case MVT::f64:     return "f64";
-  case MVT::f80:     return "f80";
-  case MVT::f128:    return "f128";
   case MVT::ppcf128: return "ppcf128";
   case MVT::isVoid:  return "isVoid";
   case MVT::Other:   return "ch";
   case MVT::Glue:    return "glue";
   case MVT::x86mmx:  return "x86mmx";
-  case MVT::v1i1:    return "v1i1";
-  case MVT::v2i1:    return "v2i1";
-  case MVT::v4i1:    return "v4i1";
-  case MVT::v8i1:    return "v8i1";
-  case MVT::v16i1:   return "v16i1";
-  case MVT::v32i1:   return "v32i1";
-  case MVT::v64i1:   return "v64i1";
-  case MVT::v128i1:  return "v128i1";
-  case MVT::v256i1:  return "v256i1";
-  case MVT::v512i1:  return "v512i1";
-  case MVT::v1024i1: return "v1024i1";
-  case MVT::v1i8:    return "v1i8";
-  case MVT::v2i8:    return "v2i8";
-  case MVT::v4i8:    return "v4i8";
-  case MVT::v8i8:    return "v8i8";
-  case MVT::v16i8:   return "v16i8";
-  case MVT::v32i8:   return "v32i8";
-  case MVT::v64i8:   return "v64i8";
-  case MVT::v128i8:  return "v128i8";
-  case MVT::v256i8:  return "v256i8";
-  case MVT::v1i16:   return "v1i16";
-  case MVT::v2i16:   return "v2i16";
-  case MVT::v3i16:   return "v3i16";
-  case MVT::v4i16:   return "v4i16";
-  case MVT::v8i16:   return "v8i16";
-  case MVT::v16i16:  return "v16i16";
-  case MVT::v32i16:  return "v32i16";
-  case MVT::v64i16:  return "v64i16";
-  case MVT::v128i16: return "v128i16";
-  case MVT::v1i32:   return "v1i32";
-  case MVT::v2i32:   return "v2i32";
-  case MVT::v3i32:   return "v3i32";
-  case MVT::v4i32:   return "v4i32";
-  case MVT::v5i32:   return "v5i32";
-  case MVT::v8i32:   return "v8i32";
-  case MVT::v16i32:  return "v16i32";
-  case MVT::v32i32:  return "v32i32";
-  case MVT::v64i32:  return "v64i32";
-  case MVT::v128i32: return "v128i32";
-  case MVT::v256i32: return "v256i32";
-  case MVT::v512i32: return "v512i32";
-  case MVT::v1024i32:return "v1024i32";
-  case MVT::v2048i32:return "v2048i32";
-  case MVT::v1i64:   return "v1i64";
-  case MVT::v2i64:   return "v2i64";
-  case MVT::v4i64:   return "v4i64";
-  case MVT::v8i64:   return "v8i64";
-  case MVT::v16i64:  return "v16i64";
-  case MVT::v32i64:  return "v32i64";
-  case MVT::v1i128:  return "v1i128";
-  case MVT::v1f32:   return "v1f32";
-  case MVT::v2f32:   return "v2f32";
-  case MVT::v2f16:   return "v2f16";
-  case MVT::v3f16:   return "v3f16";
-  case MVT::v4f16:   return "v4f16";
-  case MVT::v8f16:   return "v8f16";
-  case MVT::v16f16:  return "v16f16";
-  case MVT::v32f16:  return "v32f16";
-  case MVT::v3f32:   return "v3f32";
-  case MVT::v4f32:   return "v4f32";
-  case MVT::v5f32:   return "v5f32";
-  case MVT::v8f32:   return "v8f32";
-  case MVT::v16f32:  return "v16f32";
-  case MVT::v32f32:  return "v32f32";
-  case MVT::v64f32:  return "v64f32";
-  case MVT::v128f32: return "v128f32";
-  case MVT::v256f32: return "v256f32";
-  case MVT::v512f32: return "v512f32";
-  case MVT::v1024f32:return "v1024f32";
-  case MVT::v2048f32:return "v2048f32";
-  case MVT::v1f64:   return "v1f64";
-  case MVT::v2f64:   return "v2f64";
-  case MVT::v4f64:   return "v4f64";
-  case MVT::v8f64:   return "v8f64";
-  case MVT::nxv1i1:  return "nxv1i1";
-  case MVT::nxv2i1:  return "nxv2i1";
-  case MVT::nxv4i1:  return "nxv4i1";
-  case MVT::nxv8i1:  return "nxv8i1";
-  case MVT::nxv16i1: return "nxv16i1";
-  case MVT::nxv32i1: return "nxv32i1";
-  case MVT::nxv1i8:  return "nxv1i8";
-  case MVT::nxv2i8:  return "nxv2i8";
-  case MVT::nxv4i8:  return "nxv4i8";
-  case MVT::nxv8i8:  return "nxv8i8";
-  case MVT::nxv16i8: return "nxv16i8";
-  case MVT::nxv32i8: return "nxv32i8";
-  case MVT::nxv1i16: return "nxv1i16";
-  case MVT::nxv2i16: return "nxv2i16";
-  case MVT::nxv4i16: return "nxv4i16";
-  case MVT::nxv8i16: return "nxv8i16";
-  case MVT::nxv16i16:return "nxv16i16";
-  case MVT::nxv32i16:return "nxv32i16";
-  case MVT::nxv1i32: return "nxv1i32";
-  case MVT::nxv2i32: return "nxv2i32";
-  case MVT::nxv4i32: return "nxv4i32";
-  case MVT::nxv8i32: return "nxv8i32";
-  case MVT::nxv16i32:return "nxv16i32";
-  case MVT::nxv32i32:return "nxv32i32";
-  case MVT::nxv1i64: return "nxv1i64";
-  case MVT::nxv2i64: return "nxv2i64";
-  case MVT::nxv4i64: return "nxv4i64";
-  case MVT::nxv8i64: return "nxv8i64";
-  case MVT::nxv16i64:return "nxv16i64";
-  case MVT::nxv32i64:return "nxv32i64";
-  case MVT::nxv2f16: return "nxv2f16";
-  case MVT::nxv4f16: return "nxv4f16";
-  case MVT::nxv8f16: return "nxv8f16";
-  case MVT::nxv1f32: return "nxv1f32";
-  case MVT::nxv2f32: return "nxv2f32";
-  case MVT::nxv4f32: return "nxv4f32";
-  case MVT::nxv8f32: return "nxv8f32";
-  case MVT::nxv16f32:return "nxv16f32";
-  case MVT::nxv1f64: return "nxv1f64";
-  case MVT::nxv2f64: return "nxv2f64";
-  case MVT::nxv4f64: return "nxv4f64";
-  case MVT::nxv8f64: return "nxv8f64";
   case MVT::Metadata:return "Metadata";
   case MVT::Untyped: return "Untyped";
   case MVT::exnref : return "exnref";
   }
 }
 
 /// getTypeForEVT - This method returns an LLVM type corresponding to the
 /// specified EVT.  For integer types, this returns an unsigned type.  Note