[llvm-branch-commits] [llvm] [CodeGen][NPM] Add a target option to control machine verifier enablement at end of default pipelines (PR #176693)

[Vikram Hegde via llvm-branch-commits]

vikramRH wrote:

> If it's not failing in expensive checks with the legacy PM with the verifier enabled, why is it tripping the verifier with the NewPM? That seems to imply an issue with the new pipeline to me.

I think there is a difference in understanding about the motivation of the change here,
1. This tries to control the machine verifier being added to the default pipelines (O0, O1...) with or without expensive checks enabled. The primary motivation was several verifier failures that I saw while doing NPM testing downstream. (i.e compiling several ROCm math libraries and applications using the AMDGPU NPM backend with expensive checks disabled).
2. Legacy PM does not enable machine verifier as part of default pipelines at all (Only IR verifiers are enabled at specific points). machine verifier would still trip if I try to compile the before said applications with expensive checks enabled compiler.
3. When I said the "expensive build checks currenlty being run for the target" in my previous comment, I was referring to the tests run as part of LLVM pre/post merge checks which I think are not exhaustive enough. (I think its just lit tests ?)



https://github.com/llvm/llvm-project/pull/176693