[flang] [llvm] [flang][llvm][OpenMP][OpenACC] Add implicit casts to omp.atomic and acc.atomic (PR #131603)

[via llvm-commits]

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@@ -386,6 +442,7 @@ void genOmpAccAtomicRead(Fortran::lower::AbstractConverter &converter,
       fir::getBase(converter.genExprAddr(fromExpr, stmtCtx));
   mlir::Value toAddress = fir::getBase(converter.genExprAddr(
       *Fortran::semantics::GetExpr(assignmentStmtVariable), stmtCtx));
+  emitImplicitCast(converter, loc, fromAddress, toAddress, elementType);
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NimishMishra wrote:

Performing the convert after the omp.atomic.read is functioning fine, but causing problems with atomic capture at the moment. Earlier (although incorrect) we were performing the convert before the omp.atomic.read, so it could be hoisted out of the atomic region. Now since the conversion is after the atomic read, we cannot really hoist the conversion operations outside the region.

I am looking into resolving this. Do you have any ideas here? We could, of course, emit a TODO and go ahead with the PR. But it would be good to solve this issue for atomic.capture too I believe, if possible

https://github.com/llvm/llvm-project/pull/131603