JIT: update simd base type when combining simd nodes for bitwise ops (d…

…otnet#106510)

If we merge two simd for bitwise ops (eg creating an AndNot), make sure to use
the simd base type of the parent (And) node when specializing the operator.

Fixes dotnet#106478.

src/coreclr/jit/lowerxarch.cpp

@@ -1430,10 +1430,9 @@ GenTree* Lowering::LowerHWIntrinsic(GenTreeHWIntrinsic* node)
         const uint8_t B = 0xCC;
         const uint8_t C = 0xAA;
 
-        var_types   simdType        = node->TypeGet();
-        CorInfoType simdBaseJitType = node->GetSimdBaseJitType();
-        var_types   simdBaseType    = node->GetSimdBaseType();
-        unsigned    simdSize        = node->GetSimdSize();
+        var_types simdType     = node->TypeGet();
+        var_types simdBaseType = node->GetSimdBaseType();
+        unsigned  simdSize     = node->GetSimdSize();
 
         GenTree* op1 = node->Op(1);
         GenTree* op2 = node->Op(2);
@@ -1455,6 +1454,10 @@ GenTree* Lowering::LowerHWIntrinsic(GenTreeHWIntrinsic* node)
                 bool       userIsScalar = false;
                 genTreeOps userOper     = userIntrin->GetOperForHWIntrinsicId(&isScalar);
 
+                // userIntrin may have re-interpreted the base type
+                //
+                simdBaseType = userIntrin->GetSimdBaseType();
+
                 if (GenTreeHWIntrinsic::OperIsBitwiseHWIntrinsic(userOper))
                 {
                     if (isOperNot && (userOper == GT_AND))

src/tests/JIT/Regression/JitBlue/Runtime_106478/Runtime_106478.cs

@@ -0,0 +1,28 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+// Found by Antigen
+// Reduced from 30.05 KB to 2.35 KB.
+// Further redued by hand
+
+using System;
+using System.Runtime.Intrinsics;
+using Xunit;
+
+public class Runtime_106478
+{
+    static Vector512<double> s_v512_double_46 = Vector512.Create(4, -4.971830985915493, -0.9789473684210527, -1.956043956043956, 2, 74.25, 1.0533333333333332, 4.033898305084746);
+    Vector512<int> v512_int_101 = Vector512<int>.Zero;
+    Vector512<int> p_v512_int_125 = Vector512<int>.Zero;
+
+    void Problem()
+    {
+        p_v512_int_125 = v512_int_101& Vector512.AsInt32(s_v512_double_46 ^ Vector512<double>.AllBitsSet);
+    }
+
+    [Fact]
+    public static void Test()
+    {
+        new Runtime_106478().Problem();
+    }
+}

src/tests/JIT/Regression/JitBlue/Runtime_106478/Runtime_106478.csproj

@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <Optimize>True</Optimize>
+  </PropertyGroup>
+  <ItemGroup>
+    <Compile Include="$(MSBuildProjectName).cs" />
+  </ItemGroup>
+</Project>