[Flang][Driver] Added support for -funique-internal-linkage-names option (#216680) The option `-funique-internal-linkage-names` appends an MD5 hash suffix `(.__uniq.<hash>)` to internal procedure names and sets `"sample-profile-suffix-elision-policy"="selected"` on those functions, enabling the sample profiler to correctly match profiles to internal procedures across compilation units. Implementation: - Added a unique hash suffix to internal procedure names when `-funique-internal-linkage-names` is enabled. The suffix is derived from the source file path and disambiguates identically named internal procedures across different compilation units, which helps accurate sample-based profiling. - Added the function attribute `"sample-profile-suffix-elision-policy"="selected"` on internal procedures in LLVM IR. This attribute is used by the LLVM sample profile loader to control suffix stripping during profile matching GitOrigin-RevId: dd33f57479c1d1d86649a1867b79be88ce04da73
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.
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.