[flang-commits] [flang] [flang] Fixed designator codegen for contiguous boxes. (PR #139003)

[Slava Zakharin via flang-commits]

================
@@ -412,12 +412,44 @@ class DesignateOpConversion
     auto indices = designate.getIndices();
     int i = 0;
     auto attrs = designate.getIsTripletAttr();
+
+    // If the shape specifies a shift and the base is not a box,
+    // then we have to subtract the lower bounds, as long as
+    // fir.array_coor does not support non-default lower bounds
+    // for non-box accesses.
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vzakhari wrote:

I was hitting "shift can only be provided with fir.box memref" error in `fir::ArrayCoorOp::verify`, but I now see a comment there saying that the codegen does support it:
```
      // TODO: it looks like PreCGRewrite and CodeGen can support
      // fir.shift with plain array reference, so we may consider
      // removing this check.
      if (!mlir::isa<fir::BaseBoxType>(getMemref().getType()))
        return emitOpError("shift can only be provided with fir.box memref");
```

I will do more investigation.

https://github.com/llvm/llvm-project/pull/139003