[PATCH] D95449: [flang] Fix problems with constant arrays with lower bounds that are not 1

[Pete Steinfeld via Phabricator via llvm-commits]

PeteSteinfeld created this revision.
PeteSteinfeld added reviewers: klausler, tskeith.
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There were two problems with constant arrays whose lower bound is not 1.
First, when folding the arrays, we were creating the folded array to have lower
bounds of 1 but not re-adjusting their lower bounds to the declared values.
Second, we were not calculating the extents correctly.  Both of these problems
led to bogus error messages.

I fixed the first problem by adjusting the lower bounds in
NonPointerInitializationExpr() in Evaluate/check-expression.cpp.  I found an
existing class and method that did exactly what was needed that was originally
designed to expand a scalar value into an array called ScalarConstantExpander.
I renamed this class to reflect its generalization to ArrayConstantMaker.

I fixed the second problem by changing the formula that calculates upper bounds
in in the function ComputeUpperBound() in Evaluate/shape.cpp.

I added tests that trigger the bogus error messages mentioned above along with
a constant folding tests that uses array operands with shapes that conform but
have different bounds.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D95449

Files:
  flang/include/flang/Evaluate/tools.h
  flang/lib/Evaluate/check-expression.cpp
  flang/lib/Evaluate/fold.cpp
  flang/lib/Evaluate/shape.cpp
  flang/test/Evaluate/folding16.f90
  flang/test/Semantics/array-constr-values.f90

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