JIT: Mask AND with zero incorrectly folded

[saucecontrol]

Description

AND between a mask and a constant zero is incorrectly folded to the mask value in net10.0.

https://github.com/dotnet/runtime/blob/2075e8ffaa8cf598dac9c09f5f690778ef1a6c8e/src/coreclr/jit/gentree.cpp#L32988-L32992

Reproduction Steps

using System.Runtime.CompilerServices;
using System.Runtime.Intrinsics;

Console.WriteLine(AndMaskZero(Vector512<int>.One));

[MethodImpl(MethodImplOptions.NoInlining)]
static Vector512<int> AndMaskZero(Vector512<int> v) =>
	Vector512.Equals(v, v) & Vector512.LessThan(v.AsUInt32(), Vector512<uint>.Zero).AsInt32();

Expected behavior

> dotnet run -c release -f net9.0

<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0>

Actual behavior

> dotnet run -c release -f net10.0

<-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1>

Regression?

Yes, worked in 9.0

Configuration

Requires AVX-512

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Tagging subscribers to this area: @JulieLeeMSFT, @dotnet/jit-contrib
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[JulieLeeMSFT]

Thanks, @saucecontrol, for the report.
@anthonycanino, can your team please take a look?
CC @kg.

[saucecontrol]

I figured this might be a good one for Copilot -- it's a one-line fix 😄

index 8093f6e2140..ba0e6f44ba4 100644
--- a/src/coreclr/jit/gentree.cpp
+++ b/src/coreclr/jit/gentree.cpp
@@ -32964,7 +32964,7 @@ GenTree* Compiler::gtFoldExprHWIntrinsic(GenTreeHWIntrinsic* tree)
                         // Handle `x & 0 == 0` and `0 & x == 0`
                         if (cnsNode->IsMaskZero())
                         {
-                            resultNode = otherNode;
+                            resultNode = gtWrapWithSideEffects(cnsNode, otherNode, GTF_ALL_EFFECT);
                             break;
                         }