Required memory PHIs are not added for un-analyzable memory stores by SSA

[SingleAccretion]

Reproduction:

static int _intStatic;

[MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.AggressiveOptimization)]
public static bool Problem()
{
 [MethodImpl(MethodImplOptions.NoInlining)]
 static void Throw()
 {
 _intStatic = 1;
 throw new Exception();
 }

 _intStatic = 2;

 try
 {
 Throw();
 _intStatic = 2;
 }
 catch (Exception)
 {
 if (_intStatic == 2)
 {
 return true;
 }
 }

 return false;
}

Call Problem().

Expected result: false.
Actual result: true.

Cause: each possible modification of globally visible memory in a protected region must induce a PHI in all reachable handlers.

Putting into Future for now as the bug is very old.

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Issue Details

---

Reproduction:

static int _intStatic;

[MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.AggressiveOptimization)]
public static bool Problem()
{
 [MethodImpl(MethodImplOptions.NoInlining)]
 static void Throw()
 {
 _intStatic = 1;
 throw new Exception();
 }

 _intStatic = 2;

 try
 {
 Throw();
 _intStatic = 2;
 }
 catch (Exception)
 {
 if (_intStatic == 2)
 {
 return true;
 }
 }

 return false;
}

Call Problem().

Expected result: false.
Actual result: true.

Cause: each possible modification of globally visible memory in a protected region must induce a PHI in all reachable handlers.

Putting into Future for now as the bug is very old.

Author:	SingleAccretion
Assignees:	-
Labels:	bug, area-CodeGen-coreclr
Milestone:	Future

[AndyAyersMS]

@jakobbotsch FYI