[PATCH] D26437: Use -fno-unit-at-a-time and -funit-at-a-time
Mehdi AMINI via llvm-commits
llvm-commits at lists.llvm.org
Sun Nov 13 10:51:39 PST 2016
mehdi_amini requested changes to this revision.
mehdi_amini added a reviewer: mehdi_amini.
mehdi_amini added a comment.
This revision now requires changes to proceed.
I planned for a long time to *remove* the "unit_at_a_time" option in the PassManager builder, I haven't read anything compelling in this thread that justifies disabling IPO right now.
If there is a bug with a particular IPO when optimizing a library, then the bug should be addressed correctly, not by disabling the IPO.
In https://reviews.llvm.org/D26437#593867, @tejohnson wrote:
> I tried to look at the history of when/why DisableUnitAtATime was added to llvm, but wasn't able to find the commit log either via git (it was moved from a different file) or via google searches.
IIRC, it was a compatibility mode from the early days to be able to match what GCC was doing.
More information about the llvm-commits