From d171635b3a54fb9e8896c9562bbedaa5f3a894cd Mon Sep 17 00:00:00 2001
From: Edward Basso <edwardebasso@gmail.com>
Date: Thu, 16 Nov 2023 08:49:21 -0800
Subject: [PATCH 1/2] Fix typo in `MLMGT<MF>::getGradSolution` when `MF` is
 different from `AMF` (#3631)

## Summary

This PR fixes a small typo in `MLMGT<MF>::getGradSolution` that causes
an error when `AMR` is distinct from `MF`. A test demonstrating the fix
is added for the case where `MF`=`MultiFab` and `AMF`=`fMultiFab`.

## Additional background

This typo was noticed when working on generalizing the `MLMG` template
to the WIP class `FabArraySet`.

## Checklist

The proposed changes:
- [x] fix a bug or incorrect behavior in AMReX
---
 Src/LinearSolvers/MLMG/AMReX_MLMG.H        | 2 +-
 Tests/LinearSolvers/EBflux_grad/MyTest.H   | 1 +
 Tests/LinearSolvers/EBflux_grad/MyTest.cpp | 4 ++++
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/Src/LinearSolvers/MLMG/AMReX_MLMG.H b/Src/LinearSolvers/MLMG/AMReX_MLMG.H
index 7fc822afa23..f1fed2d3db3 100644
--- a/Src/LinearSolvers/MLMG/AMReX_MLMG.H
+++ b/Src/LinearSolvers/MLMG/AMReX_MLMG.H
@@ -545,7 +545,7 @@ MLMGT<MF>::getGradSolution (const Vector<Array<AMF*,AMREX_SPACEDIM> >& a_grad_so
             }
             linop.compGrad(alev, GetArrOfPtrs(grad_sol), sol[alev], a_loc);
             for (int idim = 0; idim < AMREX_SPACEDIM; ++idim) {
-                a_grad_sol[alev][idim]->LocalCopy(grad_sol, 0, 0, ncomp, IntVect(0));
+                a_grad_sol[alev][idim]->LocalCopy(grad_sol[idim], 0, 0, ncomp, IntVect(0));
             }
         }
     }
diff --git a/Tests/LinearSolvers/EBflux_grad/MyTest.H b/Tests/LinearSolvers/EBflux_grad/MyTest.H
index 17ccdec1604..f26ee4e1c0b 100644
--- a/Tests/LinearSolvers/EBflux_grad/MyTest.H
+++ b/Tests/LinearSolvers/EBflux_grad/MyTest.H
@@ -45,6 +45,7 @@ private:
     amrex::Vector<amrex::MultiFab> phi;
     amrex::Vector<amrex::Array<amrex::MultiFab, AMREX_SPACEDIM>> flux;
     amrex::Vector<amrex::Array<amrex::MultiFab, AMREX_SPACEDIM>> grad;
+    amrex::Vector<amrex::Array<amrex::fMultiFab, AMREX_SPACEDIM>> fgrad; // Used to test getGradSolution when MF is different from AMF
     amrex::Vector<amrex::MultiFab> rhs;
     amrex::Vector<amrex::MultiFab> acoef;
     amrex::Vector<amrex::Array<amrex::MultiFab,AMREX_SPACEDIM> > bcoef;
diff --git a/Tests/LinearSolvers/EBflux_grad/MyTest.cpp b/Tests/LinearSolvers/EBflux_grad/MyTest.cpp
index 782f3eece39..c814536203d 100644
--- a/Tests/LinearSolvers/EBflux_grad/MyTest.cpp
+++ b/Tests/LinearSolvers/EBflux_grad/MyTest.cpp
@@ -73,6 +73,7 @@ MyTest::solve ()
     mlmg.solve(amrex::GetVecOfPtrs(phi), amrex::GetVecOfConstPtrs(rhs), tol_rel, tol_abs);
     mlmg.getFluxes(amrex::GetVecOfArrOfPtrs(flux));
     mlmg.getGradSolution(amrex::GetVecOfArrOfPtrs(grad));
+    mlmg.getGradSolution(amrex::GetVecOfArrOfPtrs(fgrad)); // Test when MF is different from AMF
     for (int ilev = 0; ilev <= max_level; ++ilev) {
         amrex::VisMF::Write(phi[0], "phi-"+std::to_string(ilev));
     }
@@ -146,6 +147,7 @@ MyTest::initData ()
     bcoef.resize(nlevels);
     flux.resize(1);
     grad.resize(1);
+    fgrad.resize(1);
     for (int ilev = 0; ilev < nlevels; ++ilev)
     {
         dmap[ilev].define(grids[ilev]);
@@ -193,5 +195,7 @@ MyTest::initData ()
                                      dmap[0], 1, 0, MFInfo(), *factory[0]);
         grad[0][idim].define(amrex::convert(grids[0],IntVect::TheDimensionVector(idim)),
                                      dmap[0], 1, 0, MFInfo(), *factory[0]);
+        fgrad[0][idim].define(amrex::convert(grids[0],IntVect::TheDimensionVector(idim)),
+                                      dmap[0], 1, 0, MFInfo(), DefaultFabFactory<BaseFab<float>>());
     }
 }

From d93f34416da3dfb5b50e5a8b0cbb3b6f78bd0569 Mon Sep 17 00:00:00 2001
From: Ankith Anil Das <46082093+ankithadas@users.noreply.github.com>
Date: Fri, 17 Nov 2023 04:57:41 +1100
Subject: [PATCH 2/2] Bug fix for amrex::Subtract when called with interger
 nghost (#3634)

## Summary
`amrex::Subtract` leads to an infinite recursion when invoked with an
integer value for nghost. To address this issue, explicit casting of the
integer to `IntVect` has been incorporated.

## Checklist

The proposed changes:
- [x] fix a bug or incorrect behavior in AMReX
- [ ] add new capabilities to AMReX
- [ ] changes answers in the test suite to more than roundoff level
- [ ] are likely to significantly affect the results of downstream AMReX
users
- [ ] include documentation in the code and/or rst files, if appropriate
---
 Src/Base/AMReX_FabArrayUtility.H | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Src/Base/AMReX_FabArrayUtility.H b/Src/Base/AMReX_FabArrayUtility.H
index 78f3355d34a..ca80a070f45 100644
--- a/Src/Base/AMReX_FabArrayUtility.H
+++ b/Src/Base/AMReX_FabArrayUtility.H
@@ -1103,7 +1103,7 @@ template <class FAB,
 void
 Subtract (FabArray<FAB>& dst, FabArray<FAB> const& src, int srccomp, int dstcomp, int numcomp, int nghost)
 {
-    Subtract(dst,src,srccomp,dstcomp,numcomp,nghost);
+    Subtract(dst,src,srccomp,dstcomp,numcomp,IntVect(nghost));
 }
 
 template <class FAB,