5 Commits

Author SHA1 Message Date
Philip Reames
4bbb5efb81 [WideableCond] Fix a nasty bug in detection of "explicit guards"
The code was failing to actually check for the presence of the call to widenable_condition.  The whole point of specifying the widenable_condition intrinsic was allowing widening transforms.  A normal branch is not widenable.  A normal branch leading to a deopt is not widenable (in general).

I added a test case via LoopPredication, but GuardWidening has an analogous bug.  Those are the only two passes actually using this utility just yet. Noticed while working on LoopPredication for non-widenable branches; POC in D60111.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357493 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-02 16:51:43 +00:00
Max Kazantsev
b92e756f41 [NFC] Add function to parse widenable conditional branches
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351803 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-22 11:21:32 +00:00
Max Kazantsev
6c515426c3 [NFC] Add detector for guards expressed as branch by widenable conditions
This patch adds a function to detect guards expressed in explicit control
flow form as branch by `and` with widenable condition intrinsic call:

    %wc = call i1 @llvm.experimental.widenable.condition()
    %guard_cond = and i1, %some_cond, %wc
    br i1 %guard_cond, label %guarded, label %deopt

  deopt:
    <maybe some non-side-effecting instructions>
    deoptimize()

This form can be used as alternative to implicit control flow guard
representation expressed by `experimental_guard` intrinsic.

Differential Revision: https://reviews.llvm.org/D56074
Reviewed By: reames


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351791 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-22 09:36:22 +00:00
Chandler Carruth
6b547686c5 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-19 08:50:56 +00:00
Max Kazantsev
187d9188f7 Re-enable "[NFC] Unify guards detection"
rL340921 has been reverted by rL340923 due to linkage dependency
from Transform/Utils to Analysis which is not allowed. In this patch
this has been fixed, a new utility function moved to Analysis.

Differential Revision: https://reviews.llvm.org/D51152


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@341014 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-30 03:39:16 +00:00