Michael Kruse 458f1aae8d
[Polly] Forward VFS from PassBuilder for IO sandboxing (#188657)
#184545 default-enables the IO sandbox in assert-builds. This causes
Clang using Polly to crash (#188568).

The issue is that `PassBuilder` uses `vfs::getRealFileSystem()` by
default which is considered a IO sandbox violation in the Clang process.
With this PR store the VFS from the `PassBuilder` from the original
`registerPollyPasses` call for creating other `PassBuilder` instances.

This PR also adds infrastructure for running Polly in `clang` (in
addition in `opt`). `opt` does not enable the sandbox such that we need
separate tests using Clang.

Closes: #188568
2026-03-28 23:55:05 +01:00
..

Polly - Polyhedral optimizations for LLVM
-----------------------------------------
http://polly.llvm.org/

Polly uses a mathematical representation, the polyhedral model, to represent and
transform loops and other control flow structures. Using an abstract
representation it is possible to reason about transformations in a more general
way and to use highly optimized linear programming libraries to figure out the
optimal loop structure. These transformations can be used to do constant
propagation through arrays, remove dead loop iterations, optimize loops for
cache locality, optimize arrays, apply advanced automatic parallelization, drive
vectorization, or they can be used to do software pipelining.