[flang][HLFIR] Use GreedyPatternRewriter in LowerHLFIRIntrinsics (#83438)

In #83253 @matthias-springer pointed out that LowerHLFIRIntrinsics.cpp
should not be using rewrite patterns with the dialect conversion driver.

The intention of this pass is to lower HLFIR intrinsic operations into
FIR so it conceptually fits dialect conversion. However, dialect
conversion is much stricter about changing types when replacing
operations. This pass sometimes looses track of array bounds, resulting
in replacements with operations with different but compatible types
(expressions of the same rank and element types but with or without
compile time known array bounds). This is difficult to accommodate with
the dialect conversion driver and so I have changed to use the greedy
pattern rewriter.

There is a lot of test churn because the greedy pattern rewriter also
performs canonicalization.

GitOrigin-RevId: 44c0bdb402271522a17704b4a18c8bf5efb55c4f
17 files changed
tree: 5c96e0f18ed0b7ef3e0baffcaacb717f07c3441f
  1. cmake/
  2. docs/
  3. examples/
  4. include/
  5. lib/
  6. module/
  7. runtime/
  8. test/
  9. tools/
  10. unittests/
  11. .clang-format
  12. .clang-tidy
  13. .drone.star
  14. .gitignore
  15. CMakeLists.txt
  16. CODE_OWNERS.TXT
  17. LICENSE.TXT
  18. README.md
README.md

Flang

Flang is a ground-up implementation of a Fortran front end written in modern C++. It started off as the f18 project (https://github.com/flang-compiler/f18) with an aim to replace the previous flang project (https://github.com/flang-compiler/flang) and address its various deficiencies. F18 was subsequently accepted into the LLVM project and rechristened as Flang.

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