Forward substitution for relops misses LCL_FLD uses

[SingleAccretion]

Reproduction:

using System;
using System.Runtime.CompilerServices;

Console.WriteLine(Problem(new() { Value = 1 }));

[MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.AggressiveOptimization)]
private static int Problem(StructWithIndex a)
{
    bool k = a.Value == 1;
    a = default;
    if (k)
    {
        return 1;
    }

    return a.Index;
}

struct StructWithIndex
{
    public int Index;
    public int Value;
}

Run with DOTNET_JitNoStructPromotion=1 and DOTNET_JitNoCSE=1.

Expected result: prints 1.
Actual result: prints 0.

Cause: the interference checks in the forward substitution algorithm use gtHasRef which does not pay attention to LCL_FLD nodes:

optRedundantRelop in BB01; jump tree is
N004 (  5,  5) [000014] ------------              *  JTRUE     void
N003 (  3,  3) [000013] J------N----              \--*  EQ        int    $142
N001 (  1,  1) [000011] ------------                 +--*  LCL_VAR   int    V02 tmp1         u:1 (last use) $141
N002 (  1,  1) [000012] ------------                 \--*  CNS_INT   int    0 $40
 ... checking previous tree
N003 (  5,  4) [000008] IA------R---              *  ASG       struct (init) $VN.Void
N002 (  3,  2) [000005] D------N----              +--*  LCL_VAR   struct<StructWithIndex, 8> V00 arg0         d:2
N001 (  1,  1) [000007] ------------              \--*  CNS_INT   int    0 $40
 -- prev tree VN is not related
 ... checking previous tree
N005 (  8,  6) [000010] -A--G---R---              *  ASG       int    $141
N004 (  1,  1) [000009] D------N----              +--*  LCL_VAR   int    V02 tmp1         d:1 $141
N003 (  8,  6) [000004] ----G-------              \--*  EQ        int    $141
N001 (  3,  4) [000002] ------------                 +--*  LCL_FLD   int    V00 arg0         u:1[+4] Fseq[Value] (last use) $140
N002 (  1,  1) [000003] ------------                 \--*  CNS_INT   int    1 $42
  -- prev tree has relop with reversed liberal VN
 -- prev tree is viable candidate for relop fwd sub!
 -- done! new jump tree is
N004 (  5,  5) [000014] ----G-------              *  JTRUE     void
N003 (  8,  6) [000021] J---G--N----              \--*  NE        int    $142
N001 (  3,  4) [000022] ------------                 +--*  LCL_FLD   int    V00 arg0         [+4] Fseq[Value] (last use) $140
N002 (  1,  1) [000023] ------------                 \--*  CNS_INT   int    1 $42

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Issue Details

---

Reproduction:

using System;
using System.Runtime.CompilerServices;

Console.WriteLine(Problem(new() { Value = 1 }));

[MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.AggressiveOptimization)]
private static int Problem(StructWithIndex a)
{
    bool k = a.Value == 1;
    a = default;
    if (k)
    {
        return 1;
    }

    return a.Index;
}

struct StructWithIndex
{
    public int Index;
    public int Value;
}

Run with DOTNET_JitNoStructPromotion=1 and DOTNET_JitNoCSE=1.

Expected result: prints 1.
Actual result: prints 0.

Cause: the interference checks in the forward substitution algorithm use gtHasRef which does not pay attention to LCL_FLD nodes:

optRedundantRelop in BB01; jump tree is
N004 (  5,  5) [000014] ------------              *  JTRUE     void
N003 (  3,  3) [000013] J------N----              \--*  EQ        int    $142
N001 (  1,  1) [000011] ------------                 +--*  LCL_VAR   int    V02 tmp1         u:1 (last use) $141
N002 (  1,  1) [000012] ------------                 \--*  CNS_INT   int    0 $40
 ... checking previous tree
N003 (  5,  4) [000008] IA------R---              *  ASG       struct (init) $VN.Void
N002 (  3,  2) [000005] D------N----              +--*  LCL_VAR   struct<StructWithIndex, 8> V00 arg0         d:2
N001 (  1,  1) [000007] ------------              \--*  CNS_INT   int    0 $40
 -- prev tree VN is not related
 ... checking previous tree
N005 (  8,  6) [000010] -A--G---R---              *  ASG       int    $141
N004 (  1,  1) [000009] D------N----              +--*  LCL_VAR   int    V02 tmp1         d:1 $141
N003 (  8,  6) [000004] ----G-------              \--*  EQ        int    $141
N001 (  3,  4) [000002] ------------                 +--*  LCL_FLD   int    V00 arg0         u:1[+4] Fseq[Value] (last use) $140
N002 (  1,  1) [000003] ------------                 \--*  CNS_INT   int    1 $42
  -- prev tree has relop with reversed liberal VN
 -- prev tree is viable candidate for relop fwd sub!
 -- done! new jump tree is
N004 (  5,  5) [000014] ----G-------              *  JTRUE     void
N003 (  8,  6) [000021] J---G--N----              \--*  NE        int    $142
N001 (  3,  4) [000022] ------------                 +--*  LCL_FLD   int    V00 arg0         [+4] Fseq[Value] (last use) $140
N002 (  1,  1) [000023] ------------                 \--*  CNS_INT   int    1 $42

Author:	SingleAccretion
Assignees:	-
Labels:	area-CodeGen-coreclr, untriaged
Milestone:	-