Where can I find the constructor of System.Numerics.Vector2?

[MinxuanZ]

code is public static Vector2 CreateFromScalar() => new Vector2(1.0f);
it generates call [System.Numerics.Vector2:.ctor(float):this] when COMPlus_EnableHWIntrinsic=0
and DOTNET_JitDump=vector2:.ctor is

****** START compiling System.Numerics.Vector2:.ctor(float):this
IL to import:
 IL_0000  02                ldarg.0
 IL_0001  03                ldarg.1
 IL_0002  03                ldarg.1
 IL_0003  28 84 2a 00 06    call         0x6002A84
 IL_0008  00                nop
 IL_0009  00                nop
 IL_000a  2a                ret

Where was this imported from?
but

runtime/src/libraries/System.Numerics.Vectors/ref/System.Numerics.Vectors.cs

Lines 404 to 409 in 4e86b1c

	public partial struct Vector2 : System.IEquatable<System.Numerics.Vector2>, System.IFormattable
	{
	public float X;
	public float Y;
	public Vector2(float value) { throw null; }
	public Vector2(float x, float y) { throw null; }

[huoyaoyuan]

The managed source is now in System.Private.CoreLib:

runtime/src/libraries/System.Private.CoreLib/src/System/Numerics/Vector2.cs

Lines 30 to 33 in 4e86b1c

	[Intrinsic]
	public Vector2(float value) : this(value, value)
	{
	}

At runtime the body is not used and JIT specially expands it:

runtime/src/coreclr/jit/simdashwintrinsic.cpp

Lines 1761 to 1805 in 4e86b1c

	case NI_Vector2_Create:
	{
	assert(retType == TYP_VOID);
	assert(simdBaseType == TYP_FLOAT);
	assert(simdSize == 8);
	if (op2->IsCnsFltOrDbl() && op3->IsCnsFltOrDbl())
	{
	GenTreeVecCon* vecCon = gtNewVconNode(TYP_SIMD8);
	float cnsVal = 0;
	vecCon->gtSimdVal.f32[0] = static_cast<float>(op2->AsDblCon()->DconValue());
	vecCon->gtSimdVal.f32[1] = static_cast<float>(op3->AsDblCon()->DconValue());
	copyBlkSrc = vecCon;
	}
	else if (areArgumentsContiguous(op2, op3))
	{
	GenTree* op2Address = CreateAddressNodeForSimdHWIntrinsicCreate(op2, simdBaseType, 8);
	copyBlkSrc = gtNewIndir(TYP_SIMD8, op2Address);
	}
	else
	{
	#if defined(TARGET_XARCH)
	IntrinsicNodeBuilder nodeBuilder(getAllocator(CMK_ASTNode), 4);
	nodeBuilder.AddOperand(0, op2);
	nodeBuilder.AddOperand(1, op3);
	nodeBuilder.AddOperand(2, gtNewZeroConNode(TYP_FLOAT));
	nodeBuilder.AddOperand(3, gtNewZeroConNode(TYP_FLOAT));
	copyBlkSrc = gtNewSimdHWIntrinsicNode(TYP_SIMD8, std::move(nodeBuilder), NI_Vector128_Create,
	simdBaseJitType, 16);
	#elif defined(TARGET_ARM64)
	copyBlkSrc =
	gtNewSimdHWIntrinsicNode(TYP_SIMD8, op2, op3, NI_Vector64_Create, simdBaseJitType, 8);
	#else
	#error Unsupported platform
	#endif // !TARGET_XARCH && !TARGET_ARM64
	}
	copyBlkDst = op1;
	break;
	}