[flang-commits] [clang] [flang] [clang][flang] Add support for -finit-local-zero (PR #159788)

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@@ -384,6 +384,159 @@ class TypeInfoConverter {
   llvm::SmallSetVector<Fortran::semantics::SymbolRef, 32> seen;
 };
 
+// Helper class to encapsulate utilities related to emission of implicit
+// assignments. `Implicit` here implies the assignment does not
+// exist in the Fortran source, but is implicit through definition
+// of one or more flagsets (like -finit-* family of flags).
+// General purpose usage of these utilities outside the
+// scope detailed here is discouraged, and is probably wrong.
+class ImplicitAssignmentGenerator {
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jeanPerier wrote:

`createSingletonFromCode` is the implementation of `achar` in lowering, you can use that directly.

For `ieee_value(x, ieee_quiet_nan)`, you can use `fir::IntrinsicLibrary::genQNan` defined [here ](project/blob/0b9ed5dc64149147aadc588d9077d80fb73a54d6/flang/include/flang/Optimizer/Builder/IntrinsicCall.h#L517C15-L517C22).

I expect you may want to support snan/inf/+inf, and while there may not be existing FIR level helper to get them, I pretty sure you can easily extract the implementation to get those from ieee_value implementation in IntrinsicCall.cpp (just like `genQNan` did).

> how we could directly emit such assignments as I exemplified here through HLFIR
Why is hlfir.assign not covering your use case? It implements the Fortran intrinsic assignment.

https://github.com/llvm/llvm-project/pull/159788