b20e063a90
This PR adds support to be able to generate `acc.bounds` operation through `MappableType`'s `generateAccBounds` when there is no fir.box entity. This is especially useful because the FIR type does not capture size information for explicit-shape arrays and current implementation relied on finding the box entity. This scenario is possible because during HLFIRtoFIR, `fir.array_coor` and `fir.box_addr` operations are often optimized to use raw address. If one tries to map the ssa value that represents such a variable, correct dimensions need extracted from the shape information held in the fir declare operation.
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.
Please note that flang is not ready yet for production usage.
Getting Started
Read more about flang in the docs directory. Start with the compiler overview.
To better understand Fortran as a language and the specific grammar accepted by flang, read Fortran For C Programmers and flang's specifications of the Fortran grammar and the OpenMP grammar.
Treatment of language extensions is covered in this document.
To understand the compilers handling of intrinsics, see the discussion of intrinsics.
To understand how a flang program communicates with libraries at runtime, see the discussion of runtime descriptors.
If you're interested in contributing to the compiler, read the style guide and also review how flang uses modern C++ features.
If you are interested in writing new documentation, follow LLVM's Markdown style guide.
Consult the Getting Started with Flang for information on building and running flang.