5 Commits

Author SHA1 Message Date
George Burgess IV
baed6422b2 Reland r338431: "Add DebugCounters to DivRemPairs"
(Previously reverted in r338442)

I'm told that the breakage came from us using an x86 triple on configs
that didn't have x86 enabled. This is remedied by moving the
debugcounter test to an x86 directory (where there's also a
opt-bisect-isel.ll test for similar reasons).

I can't repro the reverse-iteration failure mentioned in the revert with
this patch, so I assume that a misconfiguration on my end is what caused
that.

Original commit message:

    Add DebugCounters to DivRemPairs

    For people who don't use DebugCounters, NFCI.

    Patch by Zhizhou Yang!

    Differential Revision: https://reviews.llvm.org/D50033



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338653 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-01 23:14:14 +00:00
George Burgess IV
0da0037233 Revert r338431: "Add DebugCounters to DivRemPairs"
This reverts r338431; the test it added is making buildbots unhappy.
Locally, I can repro the failure on reverse-iteration builds.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338442 91177308-0d34-0410-b5e6-96231b3b80d8
2018-07-31 21:18:44 +00:00
George Burgess IV
2f227c480a Add DebugCounters to DivRemPairs
For people who don't use DebugCounters, NFCI.

Patch by Zhizhou Yang!

Differential Revision: https://reviews.llvm.org/D50033


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338431 91177308-0d34-0410-b5e6-96231b3b80d8
2018-07-31 20:07:46 +00:00
Geoff Berry
b99fab9a2a [DivRemPairs] Fix non-determinism in use list order.
Summary:
Use a MapVector instead of a DenseMap for RemMap since it is iteratated
over and the order of iteration can effect the order that new
instructions are created.  This can in turn effect the use list order of
div/rem input values if multiple new instructions are created that share
any input values.

Reviewers: spatel

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D45858

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@330792 91177308-0d34-0410-b5e6-96231b3b80d8
2018-04-25 02:17:56 +00:00
Sanjay Patel
193e898f75 [DivRempairs] add a pass to optimize div/rem pairs (PR31028)
This is intended to be a superset of the functionality from D31037 (EarlyCSE) but implemented 
as an independent pass, so there's no stretching of scope and feature creep for an existing pass. 
I also proposed a weaker version of this for SimplifyCFG in D30910. And I initially had almost 
this same functionality as an addition to CGP in the motivating example of PR31028:
https://bugs.llvm.org/show_bug.cgi?id=31028

The advantage of positioning this ahead of SimplifyCFG in the pass pipeline is that it can allow 
more flattening. But it needs to be after passes (InstCombine) that could sink a div/rem and
undo the hoisting that is done here.

Decomposing remainder may allow removing some code from the backend (PPC and possibly others).

Differential Revision: https://reviews.llvm.org/D37121 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312862 91177308-0d34-0410-b5e6-96231b3b80d8
2017-09-09 13:38:18 +00:00