As defined in LangRef, branching on `undef` is undefined behavior.
This PR aims to remove undefined behavior from tests. As UB tests break
Alive2 and may be the root cause of breaking future optimizations.
Here's an Alive2 proof for one of the examples:
https://alive2.llvm.org/ce/z/TncxhP
This is part of effort in removing -enable-new-pm flag.
As a prat of this effort one of example passes SimplifyCFG must
be ported to new PM which will allow to remove the flag
calls from the tests that are using this pass.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D137103
After fffabd53482f34f96ab9273486538f587e3d91fc, the v2 and v3
versions produce poison instead of undef. Also adjust the v1
version, as well as the test expectations, to make the example
pass again.
tut-simplify-cfg hasn't been ported to the new PM.
llvm-lto2's -enable-new-pm defaults to the CMake flag, so the legacy PM extension test needs to be pinned.
Reviewed By: MaskRay, ychen
Differential Revision: https://reviews.llvm.org/D95898
This breaks LLVMExports.cmake in some build configurations.
PR44197
This reverts commits ceb72d07b004af9c428c4a3c73a98ea97d49a713
7d0b1d77b3d4d47df477519fd1bf099b3df6f899.
This patch adds a new IRTransformations directory to llvm/examples/. This is
intended to serve as a new home for example transformations/analysis
code used by various tutorials.
If LLVM_BUILD_EXAMPLES is enabled, the ExamplesIRTransforms library is
linked into the opt binary and the example passes become available.
To start off with, it contains the CFG simplifications used in the IR
part of the 'Getting Started With LLVM: Basics' tutorial at the US LLVM
Developers Meeting 2019.
Reviewers: paquette, jfb, meikeb, lhames, kbarton
Reviewed By: paquette
Differential Revision: https://reviews.llvm.org/D69416
