Commit Graph

204 Commits

Author SHA1 Message Date
Eugene Zelenko
13bc67e541 [Target, Transforms] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292320 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-18 00:57:48 +00:00
Peter Collingbourne
1d8008b2d3 Re-apply r291205, "LowerTypeTests: Split the pass in two: a resolution phase and a lowering phase.", with a fix for an off-by-one error.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291699 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-11 20:28:46 +00:00
Ivan Krasin
52a39de25f Revert rL291205 because it breaks Chrome tests under CFI.
Summary:
Revert LowerTypeTests: Split the pass in two: a resolution phase and a lowering phase.

This change separates how type identifiers are resolved from how intrinsic
calls are lowered. All information required to lower an intrinsic call
is stored in a new TypeIdLowering data structure. The idea is that this
data structure can either be initialized using the module itself during
regular LTO, or using the module summary in ThinLTO backends.

Original URL: https://reviews.llvm.org/D28341

Reviewers: pcc

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D28532

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291684 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-11 16:54:04 +00:00
Mehdi Amini
9cb6a18769 Remove useless Forward Declaration from header (NFC)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291321 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-07 00:57:43 +00:00
Peter Collingbourne
d99c988733 LowerTypeTests: Split the pass in two: a resolution phase and a lowering phase.
This change separates how type identifiers are resolved from how intrinsic
calls are lowered. All information required to lower an intrinsic call
is stored in a new TypeIdLowering data structure. The idea is that this
data structure can either be initialized using the module itself during
regular LTO, or using the module summary in ThinLTO backends.

Differential Revision: https://reviews.llvm.org/D28341

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291205 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-06 02:22:47 +00:00
Teresa Johnson
a4ca999339 ThinLTO: add early "dead-stripping" on the Index
Summary:
Using the linker-supplied list of "preserved" symbols, we can compute
the list of "dead" symbols, i.e. the one that are not reachable from
a "preserved" symbol transitively on the reference graph.
Right now we are using this information to mark these functions as
non-eligible for import.

The impact is two folds:
- Reduction of compile time: we don't import these functions anywhere
  or import the function these symbols are calling.
- The limited number of import/export leads to better internalization.

Patch originally by Mehdi Amini.

Reviewers: mehdi_amini, pcc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D23488

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291177 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-05 21:34:18 +00:00
Davide Italiano
2d42f75ba5 [NewGVN] Add a flag to enable the pass via -mllvm.
NewGVN can be tested passing `-mllvm -enable-newgvn` to clang.

Differential Revision:  https://reviews.llvm.org/D28059

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290548 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-26 18:26:19 +00:00
Peter Collingbourne
83179504e5 IPO: Remove the ModuleSummary argument to the FunctionImport pass. NFCI.
No existing client is passing a non-null value here. This will come back
in a slightly different form as part of the type identifier summary work.

Differential Revision: https://reviews.llvm.org/D28006

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290222 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-21 00:50:12 +00:00
Chandler Carruth
54cffa1811 [PM] Provide an initial, minimal port of the inliner to the new pass manager.
This doesn't implement *every* feature of the existing inliner, but
tries to implement the most important ones for building a functional
optimization pipeline and beginning to sort out bugs, regressions, and
other problems.

Notable, but intentional omissions:
- No alloca merging support. Why? Because it isn't clear we want to do
  this at all. Active discussion and investigation is going on to remove
  it, so for simplicity I omitted it.
- No support for trying to iterate on "internally" devirtualized calls.
  Why? Because it adds what I suspect is inappropriate coupling for
  little or no benefit. We will have an outer iteration system that
  tracks devirtualization including that from function passes and
  iterates already. We should improve that rather than approximate it
  here.
- Optimization remarks. Why? Purely to make the patch smaller, no other
  reason at all.

The last one I'll probably work on almost immediately. But I wanted to
skip it in the initial patch to try to focus the change as much as
possible as there is already a lot of code moving around and both of
these *could* be skipped without really disrupting the core logic.

A summary of the different things happening here:

1) Adding the usual new PM class and rigging.

2) Fixing minor underlying assumptions in the inline cost analysis or
   inline logic that don't generally hold in the new PM world.

3) Adding the core pass logic which is in essence a loop over the calls
   in the nodes in the call graph. This is a bit duplicated from the old
   inliner, but only a handful of lines could realistically be shared.
   (I tried at first, and it really didn't help anything.) All told,
   this is only about 100 lines of code, and most of that is the
   mechanics of wiring up analyses from the new PM world.

4) Updating the LazyCallGraph (in the new PM) based on the *newly
   inlined* calls and references. This is very minimal because we cannot
   form cycles.

5) When inlining removes the last use of a function, eagerly nuking the
   body of the function so that any "one use remaining" inline cost
   heuristics are immediately refined, and queuing these functions to be
   completely deleted once inlining is complete and the call graph
   updated to reflect that they have become dead.

6) After all the inlining for a particular function, updating the
   LazyCallGraph and the CGSCC pass manager to reflect the
   function-local simplifications that are done immediately and
   internally by the inline utilties. These are the exact same
   fundamental set of CG updates done by arbitrary function passes.

7) Adding a bunch of test cases to specifically target CGSCC and other
   subtle aspects in the new PM world.

Many thanks to the careful review from Easwaran and Sanjoy and others!

Differential Revision: https://reviews.llvm.org/D24226

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290161 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-20 03:15:32 +00:00
Daniel Jasper
8de3a54f07 Revert @llvm.assume with operator bundles (r289755-r289757)
This creates non-linear behavior in the inliner (see more details in
r289755's commit thread).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290086 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-19 08:22:17 +00:00
Hal Finkel
bffeba468d Remove the AssumptionCache
After r289755, the AssumptionCache is no longer needed. Variables affected by
assumptions are now found by using the new operand-bundle-based scheme. This
new scheme is more computationally efficient, and also we need much less
code...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289756 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-15 03:02:15 +00:00
Dehao Chen
932f24fa52 Create SampleProfileLoader pass in llvm instead of clang
Summary: We used to create SampleProfileLoader pass in clang. This makes LTO/ThinLTO unable to add this pass in the linker plugin. This patch moves the SampleProfileLoader pass creation from clang to llvm pass manager builder.

Reviewers: tejohnson, davidxl, dnovillo

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D27743

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289714 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-14 21:40:47 +00:00
Dehao Chen
5e64d8cf08 revert r289669 which breaks bots
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289676 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-14 17:23:16 +00:00
Dehao Chen
99c2801179 Create SampleProfileLoader pass in llvm instead of clang
Summary: We used to create SampleProfileLoader pass in clang. This makes LTO/ThinLTO unable to add this pass in the linker plugin. This patch moves the SampleProfileLoader pass creation from clang to llvm pass manager builder.

Reviewers: tejohnson, davidxl, dnovillo

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D27743

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289669 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-14 16:49:28 +00:00
Davide Italiano
02ca2cb0e6 [GlobalSplit] Port to the new pass manager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287511 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-21 00:28:23 +00:00
Peter Collingbourne
dead081fb2 Bitcode: Change module reader functions to return an llvm::Expected.
Differential Revision: https://reviews.llvm.org/D26562

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286752 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-13 07:00:17 +00:00
Peter Collingbourne
76c218e094 Bitcode: Change the materializer interface to return llvm::Error.
Differential Revision: https://reviews.llvm.org/D26439

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286382 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-09 17:49:19 +00:00
Chandler Carruth
377af8df2b [PM] Introduce basic update capabilities to the new PM's CGSCC pass
manager, including both plumbing and logic to handle function pass
updates.

There are three fundamentally tied changes here:
1) Plumbing *some* mechanism for updating the CGSCC pass manager as the
   CG changes while passes are running.
2) Changing the CGSCC pass manager infrastructure to have support for
   the underlying graph to mutate mid-pass run.
3) Actually updating the CG after function passes run.

I can separate them if necessary, but I think its really useful to have
them together as the needs of #3 drove #2, and that in turn drove #1.

The plumbing technique is to extend the "run" method signature with
extra arguments. We provide the call graph that intrinsically is
available as it is the basis of the pass manager's IR units, and an
output parameter that records the results of updating the call graph
during an SCC passes's run. Note that "...UpdateResult" isn't a *great*
name here... suggestions very welcome.

I tried a pretty frustrating number of different data structures and such
for the innards of the update result. Every other one failed for one
reason or another. Sometimes I just couldn't keep the layers of
complexity right in my head. The thing that really worked was to just
directly provide access to the underlying structures used to walk the
call graph so that their updates could be informed by the *particular*
nature of the change to the graph.

The technique for how to make the pass management infrastructure cope
with mutating graphs was also something that took a really, really large
number of iterations to get to a place where I was happy. Here are some
of the considerations that drove the design:

- We operate at three levels within the infrastructure: RefSCC, SCC, and
  Node. In each case, we are working bottom up and so we want to
  continue to iterate on the "lowest" node as the graph changes. Look at
  how we iterate over nodes in an SCC running function passes as those
  function passes mutate the CG. We continue to iterate on the "lowest"
  SCC, which is the one that continues to contain the function just
  processed.

- The call graph structure re-uses SCCs (and RefSCCs) during mutation
  events for the *highest* entry in the resulting new subgraph, not the
  lowest. This means that it is necessary to continually update the
  current SCC or RefSCC as it shifts. This is really surprising and
  subtle, and took a long time for me to work out. I actually tried
  changing the call graph to provide the opposite behavior, and it
  breaks *EVERYTHING*. The graph update algorithms are really deeply
  tied to this particualr pattern.

- When SCCs or RefSCCs are split apart and refined and we continually
  re-pin our processing to the bottom one in the subgraph, we need to
  enqueue the newly formed SCCs and RefSCCs for subsequent processing.
  Queuing them presents a few challenges:
  1) SCCs and RefSCCs use wildly different iteration strategies at
     a high level. We end up needing to converge them on worklist
     approaches that can be extended in order to be able to handle the
     mutations.
  2) The order of the enqueuing need to remain bottom-up post-order so
     that we don't get surprising order of visitation for things like
     the inliner.
  3) We need the worklists to have set semantics so we don't duplicate
     things endlessly. We don't need a *persistent* set though because
     we always keep processing the bottom node!!!! This is super, super
     surprising to me and took a long time to convince myself this is
     correct, but I'm pretty sure it is... Once we sink down to the
     bottom node, we can't re-split out the same node in any way, and
     the postorder of the current queue is fixed and unchanging.
  4) We need to make sure that the "current" SCC or RefSCC actually gets
     enqueued here such that we re-visit it because we continue
     processing a *new*, *bottom* SCC/RefSCC.

- We also need the ability to *skip* SCCs and RefSCCs that get merged
  into a larger component. We even need the ability to skip *nodes* from
  an SCC that are no longer part of that SCC.

This led to the design you see in the patch which uses SetVector-based
worklists. The RefSCC worklist is always empty until an update occurs
and is just used to handle those RefSCCs created by updates as the
others don't even exist yet and are formed on-demand during the
bottom-up walk. The SCC worklist is pre-populated from the RefSCC, and
we push new SCCs onto it and blacklist existing SCCs on it to get the
desired processing.

We then *directly* update these when updating the call graph as I was
never able to find a satisfactory abstraction around the update
strategy.

Finally, we need to compute the updates for function passes. This is
mostly used as an initial customer of all the update mechanisms to drive
their design to at least cover some real set of use cases. There are
a bunch of interesting things that came out of doing this:

- It is really nice to do this a function at a time because that
  function is likely hot in the cache. This means we want even the
  function pass adaptor to support online updates to the call graph!

- To update the call graph after arbitrary function pass mutations is
  quite hard. We have to build a fairly comprehensive set of
  data structures and then process them. Fortunately, some of this code
  is related to the code for building the cal graph in the first place.
  Unfortunately, very little of it makes any sense to share because the
  nature of what we're doing is so very different. I've factored out the
  one part that made sense at least.

- We need to transfer these updates into the various structures for the
  CGSCC pass manager. Once those were more sanely worked out, this
  became relatively easier. But some of those needs necessitated changes
  to the LazyCallGraph interface to make it significantly easier to
  extract the changed SCCs from an update operation.

- We also need to update the CGSCC analysis manager as the shape of the
  graph changes. When an SCC is merged away we need to clear analyses
  associated with it from the analysis manager which we didn't have
  support for in the analysis manager infrsatructure. New SCCs are easy!
  But then we have the case that the original SCC has its shape changed
  but remains in the call graph. There we need to *invalidate* the
  analyses associated with it.

- We also need to invalidate analyses after we *finish* processing an
  SCC. But the analyses we need to invalidate here are *only those for
  the newly updated SCC*!!! Because we only continue processing the
  bottom SCC, if we split SCCs apart the original one gets invalidated
  once when its shape changes and is not processed farther so its
  analyses will be correct. It is the bottom SCC which continues being
  processed and needs to have the "normal" invalidation done based on
  the preserved analyses set.

All of this is mostly background and context for the changes here.

Many thanks to all the reviewers who helped here. Especially Sanjoy who
caught several interesting bugs in the graph algorithms, David, Sean,
and others who all helped with feedback.

Differential Revision: http://reviews.llvm.org/D21464

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279618 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-24 09:37:14 +00:00
Chandler Carruth
b699f7b88f [PM] Port the always inliner to the new pass manager in a much more
minimal and boring form than the old pass manager's version.

This pass does the very minimal amount of work necessary to inline
functions declared as always-inline. It doesn't support a wide array of
things that the legacy pass manager did support, but is alse ... about
20 lines of code. So it has that going for it. Notably things this
doesn't support:

- Array alloca merging
  - To support the above, bottom-up inlining with careful history
    tracking and call graph updates
- DCE of the functions that become dead after this inlining.
- Inlining through call instructions with the always_inline attribute.
  Instead, it focuses on inlining functions with that attribute.

The first I've omitted because I'm hoping to just turn it off for the
primary pass manager. If that doesn't pan out, I can add it here but it
will be reasonably expensive to do so.

The second should really be handled by running global-dce after the
inliner. I don't want to re-implement the non-trivial logic necessary to
do comdat-correct DCE of functions. This means the -O0 pipeline will
have to be at least 'always-inline,global-dce', but that seems
reasonable to me. If others are seriously worried about this I'd like to
hear about it and understand why. Again, this is all solveable by
factoring that logic into a utility and calling it here, but I'd like to
wait to do that until there is a clear reason why the existing
pass-based factoring won't work.

The final point is a serious one. I can fairly easily add support for
this, but it seems both costly and a confusing construct for the use
case of the always inliner running at -O0. This attribute can of course
still impact the normal inliner easily (although I find that
a questionable re-use of the same attribute). I've started a discussion
to sort out what semantics we want here and based on that can figure out
if it makes sense ta have this complexity at O0 or not.

One other advantage of this design is that it should be quite a bit
faster due to checking for whether the function is a viable candidate
for inlining exactly once per function instead of doing it for each call
site.

Anyways, hopefully a reasonable starting point for this pass.

Differential Revision: https://reviews.llvm.org/D23299

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278896 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-17 02:56:20 +00:00
Mehdi Amini
055f556eae [LTO] Simplify APIs and constify (NFC)
Summary:
Multiple APIs were taking a StringMap for the ImportLists containing
the entries for for all the modules while operating on a single entry
for the current module. Instead we can pass the desired ModuleImport
directly. Also some of the APIs were not const, I believe just to be
able to use operator[] on the StringMap.

Reviewers: tejohnson

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D23537

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278776 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-16 05:46:05 +00:00
Ivan Krasin
88add6b31b WholeProgramDevirt: fix access to a non-initialized field.
Summary: This is a follow up to r278389, where I have introduced the bug

Reviewers: mehdi_amini

Differential Revision: https://reviews.llvm.org/D23436

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278442 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-12 00:07:14 +00:00
Ivan Krasin
dcedd3b6ff WholeProgramDevirt: generate more detailed and accurate remarks.
Summary:
Keep track of all methods for which we have devirtualized at least
one call and then print them sorted alphabetically. That allows to
avoid duplicates and also makes the order deterministic.

Add optimization names into the remarks, so that it's easier to
understand how has each method been devirtualized.

Fix a bug when wrong methods could have been reported for
tryVirtualConstProp.

Reviewers: kcc, mehdi_amini

Differential Revision: https://reviews.llvm.org/D23297

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278389 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-11 19:09:02 +00:00
Adam Nemet
37a4ac8678 [Inliner,OptDiag] Add hotness attribute to opt diagnostics
Summary:
The inliner not being a function pass requires the work-around of
generating the OptimizationRemarkEmitter and in turn BFI on demand.
This will go away after the new PM is ready.

BFI is only computed inside ORE if the user has requested hotness
information for optimization diagnostitics (-pass-remark-with-hotness at
the 'opt' level).  Thus there is no additional overhead without the
flag.

Reviewers: hfinkel, davidxl, eraman

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D22694

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278185 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-10 00:44:44 +00:00
Sean Silva
2fb9a98752 Consistently use ModuleAnalysisManager
Besides a general consistently benefit, the extra layer of indirection
allows the mechanical part of https://reviews.llvm.org/D23256 that
requires touching every transformation and analysis to be factored out
cleanly.

Thanks to David for the suggestion.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278078 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-09 00:28:38 +00:00
Chandler Carruth
c9e642268a [Inliner] Clean up doxygen comments to match modern style.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277417 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-02 05:49:32 +00:00
Piotr Padlewski
d7e3771d59 Added ThinLTO inlining statistics
Summary:
copypasta doc of ImportedFunctionsInliningStatistics class
 \brief Calculate and dump ThinLTO specific inliner stats.
 The main statistics are:
 (1) Number of inlined imported functions,
 (2) Number of imported functions inlined into importing module (indirect),
 (3) Number of non imported functions inlined into importing module
 (indirect).
 The difference between first and the second is that first stat counts
 all performed inlines on imported functions, but the second one only the
 functions that have been eventually inlined to a function in the importing
 module (by a chain of inlines). Because llvm uses bottom-up inliner, it is
 possible to e.g. import function `A`, `B` and then inline `B` to `A`,
 and after this `A` might be too big to be inlined into some other function
 that calls it. It calculates this statistic by building graph, where
 the nodes are functions, and edges are performed inlines and then by marking
 the edges starting from not imported function.

 If `Verbose` is set to true, then it also dumps statistics
 per each inlined function, sorted by the greatest inlines count like
 - number of performed inlines
 - number of performed inlines to importing module

Reviewers: eraman, tejohnson, mehdi_amini

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D22491

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277089 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-29 00:27:16 +00:00
David Majnemer
22e3ed1aa0 Add EP_CGSCCOptimizerLate extension point to PassManagerBuilder
The EP_CGSCCOptimizerLate extension point allows adding CallGraphSCC
passes at the end of the main CallGraphSCC passes and before any
function simplification passes run by CGPassManager.

Patch by Gor Nishanov!

Differential Revision: https://reviews.llvm.org/D22897

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276953 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-28 03:28:43 +00:00
Sean Silva
4cd349418b Fix : Partial Inliner requires AssumptionCacheTracker
The public InlineFunction utility assumes that the passed in
InlineFunctionInfo has a valid AssumptionCacheTracker.

Patch by River Riddle!

Differential Revision: https://reviews.llvm.org/D22706

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276609 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-25 05:00:00 +00:00
Xinliang David Li
52e0b0d91b [Profile] Use explicit flag to enable IR PGO
Patch by Jake VanAdrighem

Differential Revision: http://reviews.llvm.org/D22607




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276516 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-23 04:28:52 +00:00
Sean Silva
9486968c02 Avoid using a raw AssumptionCacheTracker in various inliner functions.
This unblocks the new PM part of River's patch in
https://reviews.llvm.org/D22706

Conveniently, this same change was needed for D21921 and so these
changes are just spun out from there.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276515 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-23 04:22:50 +00:00
Teresa Johnson
385d70633e [PM] Port FunctionImport Pass to new PM
Summary: Port FunctionImport Pass to new PM.

Reviewers: mehdi_amini, davide

Subscribers: davidxl, llvm-commits

Differential Revision: https://reviews.llvm.org/D22475

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275916 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-18 21:22:24 +00:00
Davide Italiano
eb0664013d [PM/IPO] Port LowerTypeTests to the new PassManager.
There's a little bit of churn in this patch because the initialization
mechanism is now shared between the old and the new PM. Other than
that, it's just a pretty mechanical translation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275082 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-11 18:10:06 +00:00
Davide Italiano
0dd611bd69 [PM] Port CrossDSOCFI to the new pass manager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274962 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-09 03:25:35 +00:00
Easwaran Raman
78b1ab747b [PM] Port PartialInlining to the new PM
Differential revision: http://reviews.llvm.org/D21699



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273894 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-27 16:50:18 +00:00
Peter Collingbourne
dba9146333 IR: New representation for CFI and virtual call optimization pass metadata.
The bitset metadata currently used in LLVM has a few problems:

1. It has the wrong name. The name "bitset" refers to an implementation
   detail of one use of the metadata (i.e. its original use case, CFI).
   This makes it harder to understand, as the name makes no sense in the
   context of virtual call optimization.

2. It is represented using a global named metadata node, rather than
   being directly associated with a global. This makes it harder to
   manipulate the metadata when rebuilding global variables, summarise it
   as part of ThinLTO and drop unused metadata when associated globals are
   dropped. For this reason, CFI does not currently work correctly when
   both CFI and vcall opt are enabled, as vcall opt needs to rebuild vtable
   globals, and fails to associate metadata with the rebuilt globals. As I
   understand it, the same problem could also affect ASan, which rebuilds
   globals with a red zone.

This patch solves both of those problems in the following way:

1. Rename the metadata to "type metadata". This new name reflects how
   the metadata is currently being used (i.e. to represent type information
   for CFI and vtable opt). The new name is reflected in the name for the
   associated intrinsic (llvm.type.test) and pass (LowerTypeTests).

2. Attach metadata directly to the globals that it pertains to, rather
   than using the "llvm.bitsets" global metadata node as we are doing now.
   This is done using the newly introduced capability to attach
   metadata to global variables (r271348 and r271358).

See also: http://lists.llvm.org/pipermail/llvm-dev/2016-June/100462.html

Differential Revision: http://reviews.llvm.org/D21053

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273729 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-24 21:21:32 +00:00
Benjamin Kramer
e5eb673413 Apply another batch of fixes from clang-tidy's performance-unnecessary-value-param.
Contains some manual fixes. No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273047 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-17 20:41:14 +00:00
Chandler Carruth
04d0fe9c10 [PM] Remove support for omitting the AnalysisManager argument to new
pass manager passes' `run` methods.

This removes a bunch of SFINAE goop from the pass manager and just
requires pass authors to accept `AnalysisManager<IRUnitT> &` as a dead
argument. This is a small price to pay for the simplicity of the system
as a whole, despite the noise that changing it causes at this stage.

This will also helpfull allow us to make the signature of the run
methods much more flexible for different kinds af passes to support
things like intelligently updating the pass's progression over IR units.

While this touches many, many, files, the changes are really boring.
Mostly made with the help of my trusty perl one liners.

Thanks to Sean and Hal for bouncing ideas for this with me in IRC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272978 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-17 00:11:01 +00:00
Davide Italiano
7c798721d2 [PM] Port WholeProgramDevirt to the new pass manager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272721 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-14 21:44:19 +00:00
Sean Silva
466d0a3f2a [PM] Port DeadArgumentElimination to the new PM
The approach taken here follows r267631.

deadarghaX0r should be easy to port when the time comes to add new-PM
support to bugpoint.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272507 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-12 09:16:39 +00:00
Sean Silva
cc691dd8da [PM] Port ReversePostOrderFunctionAttrs to the new PM
Below are my super rough notes when porting. They can probably serve as
a basic guide for porting other passes to the new PM. As I port more
passes I'll expand and generalize this and make a proper
docs/HowToPortToNewPassManager.rst document. There is also missing
documentation for general concepts and API's in the new PM which will
require some documentation.
Once there is proper documentation in place we can put up a list of
passes that have to be ported and game-ify/crowdsource the rest of the
porting (at least of the middle end; the backend is still unclear).

I will however be taking personal responsibility for ensuring that the
LLD/ELF LTO pipeline is ported in a timely fashion. The remaining passes
to be ported are (do something like
`git grep "<the string in the bullet point below>"` to find the pass):

General Scalar:
[ ] Simplify the CFG
[ ] Jump Threading
[ ] MemCpy Optimization
[ ] Promote Memory to Register
[ ] MergedLoadStoreMotion
[ ] Lazy Value Information Analysis

General IPO:
[ ] Dead Argument Elimination
[ ] Deduce function attributes in RPO

Loop stuff / vectorization stuff:
[ ] Alignment from assumptions
[ ] Canonicalize natural loops
[ ] Delete dead loops
[ ] Loop Access Analysis
[ ] Loop Invariant Code Motion
[ ] Loop Vectorization
[ ] SLP Vectorizer
[ ] Unroll loops

Devirtualization / CFI:
[ ] Cross-DSO CFI
[ ] Whole program devirtualization
[ ] Lower bitset metadata

CGSCC passes:
[ ] Function Integration/Inlining
[ ] Remove unused exception handling info
[ ] Promote 'by reference' arguments to scalars

Please let me know if you are interested in working on any of the passes
in the above list (e.g. reply to the post-commit thread for this patch).
I'll probably be tackling "General Scalar" and "General IPO" first FWIW.

Steps as I port "Deduce function attributes in RPO"
---------------------------------------------------

(note: if you are doing any work based on these notes, please leave a
note in the post-commit review thread for this commit with any
improvements / suggestions / incompleteness you ran into!)

Note: "Deduce function attributes in RPO" is a module pass.

1. Do preparatory refactoring.

Do preparatory factoring. In this case all I had to do was to pull out a static helper (r272503).
(TODO: give more advice here e.g. if pass holds state or something)

2. Rename the old pass class.

llvm/lib/Transforms/IPO/FunctionAttrs.cpp
Rename class ReversePostOrderFunctionAttrs -> ReversePostOrderFunctionAttrsLegacyPass
in preparation for adding a class ReversePostOrderFunctionAttrs as the pass in the new PM.
(edit: actually wait what? The new class name will be
ReversePostOrderFunctionAttrsPass, so it doesn't conflict. So this step is
sort of useless churn).

llvm/include/llvm/InitializePasses.h
llvm/lib/LTO/LTOCodeGenerator.cpp
llvm/lib/Transforms/IPO/IPO.cpp
llvm/lib/Transforms/IPO/FunctionAttrs.cpp
Rename initializeReversePostOrderFunctionAttrsPass -> initializeReversePostOrderFunctionAttrsLegacyPassPass
(note that the "PassPass" thing falls out of `s/ReversePostOrderFunctionAttrs/ReversePostOrderFunctionAttrsLegacyPass/`)
Note that the INITIALIZE_PASS macro is what creates this identifier name, so renaming the class requires this renaming too.

Note that createReversePostOrderFunctionAttrsPass does not need to be
renamed since its name is not generated from the class name.

3. Add the new PM pass class.

In the new PM all passes need to have their
declaration in a header somewhere, so you will often need to add a header.
In this case
llvm/include/llvm/Transforms/IPO/FunctionAttrs.h is already there because
PostOrderFunctionAttrsPass was already ported.
The file-level comment from the .cpp file can be used as the file-level
comment for the new header. You may want to tweak the wording slightly
from "this file implements" to "this file provides" or similar.

Add declaration for the new PM pass in this header:

    class ReversePostOrderFunctionAttrsPass
        : public PassInfoMixin<ReversePostOrderFunctionAttrsPass> {
    public:
      PreservedAnalyses run(Module &M, AnalysisManager<Module> &AM);
    };

Its name should end with `Pass` for consistency (note that this doesn't
collide with the names of most old PM passes). E.g. call it
`<name of the old PM pass>Pass`.

Also, move the doxygen comment from the old PM pass to the declaration of
this class in the header.
Also, include the declaration for the new PM class
`llvm/Transforms/IPO/FunctionAttrs.h` at the top of the file (in this case,
it was already done when the other pass in this file was ported).

Now define the `run` method for the new class.
The main things here are:
a) Use AM.getResult<...>(M) to get results instead of `getAnalysis<...>()`

b) If the old PM pass would have returned "false" (i.e. `Changed ==
false`), then you should return PreservedAnalyses::all();

c) In the old PM getAnalysisUsage method, observe the calls
   `AU.addPreserved<...>();`.

   In the case `Changed == true`, for each preserved analysis you should do
   call `PA.preserve<...>()` on a PreservedAnalyses object and return it.
   E.g.:

       PreservedAnalyses PA;
       PA.preserve<CallGraphAnalysis>();
       return PA;

Note that calls to skipModule/skipFunction are not supported in the new PM
currently, so optnone and optimization bisect support do not work. You can
just drop those calls for now.

4. Add the pass to the new PM pass registry to make it available in opt.

In llvm/lib/Passes/PassBuilder.cpp add a #include for your header.
`#include "llvm/Transforms/IPO/FunctionAttrs.h"`
In this case there is already an include (from when
PostOrderFunctionAttrsPass was ported).

Add your pass to llvm/lib/Passes/PassRegistry.def
In this case, I added
`MODULE_PASS("rpo-functionattrs", ReversePostOrderFunctionAttrsPass())`
The string is from the `INITIALIZE_PASS*` macros used in the old pass
manager.

Then choose a test that uses the pass and use the new PM `-passes=...` to
run it.
E.g. in this case there is a test that does:
; RUN: opt < %s -basicaa -functionattrs -rpo-functionattrs -S | FileCheck %s
I have added the line:
; RUN: opt < %s -aa-pipeline=basic-aa -passes='require<targetlibinfo>,cgscc(function-attrs),rpo-functionattrs' -S | FileCheck %s
The `-aa-pipeline=basic-aa` and
`require<targetlibinfo>,cgscc(function-attrs)` are what is needed to run
functionattrs in the new PM (note that in the new PM "functionattrs"
becomes "function-attrs" for some reason). This is just pulled from
`readattrs.ll` which contains the change from when functionattrs was ported
to the new PM.
Adding rpo-functionattrs causes the pass that was just ported to run.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272505 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-12 07:48:51 +00:00
Easwaran Raman
f8bdcad7be Use ProfileSummaryInfo in inline cost analysis.
Instead of directly using MaxFunctionCount and function entry count to determine callee hotness, use the isHotFunction/isColdFunction methods provided by ProfileSummaryInfo.

Differential revision: http://reviews.llvm.org/D21045


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272321 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-09 22:23:21 +00:00
Benjamin Kramer
14aae01bc3 Apply clang-tidy's misc-move-constructor-init throughout LLVM.
No functionality change intended, maybe a tiny performance improvement.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270997 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-27 14:27:24 +00:00
Peter Collingbourne
03ef7f1eec Move whole-program virtual call optimization pass after function attribute inference in LTO pipeline.
As a result of D18634 we no longer infer certain attributes on linkonce_odr
functions at compile time, and may only infer them at LTO time. The readnone
attribute in particular is required for virtual constant propagation (part
of whole-program virtual call optimization) to work correctly.

This change moves the whole-program virtual call optimization pass after
the function attribute inference passes, and enables the attribute inference
passes at opt level 1, so that virtual constant propagation has a chance to
work correctly for linkonce_odr functions.

Differential Revision: http://reviews.llvm.org/D20643

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270765 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-25 21:26:14 +00:00
Teresa Johnson
32d095cbbc [ThinLTO] Refactor ODR resolution and internalization (NFC)
Move the now index-based ODR resolution and internalization routines out
of ThinLTOCodeGenerator.cpp and into either LTO.cpp (index-based
analysis) or FunctionImport.cpp (index-driven optimizations).
This is to enable usage by other linkers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270698 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-25 14:03:11 +00:00
Andrew Kaylor
312768009e Avoid including AlwaysInliner pass in opt-bisect search.
Differential Revision: http://reviews.llvm.org/D19640



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270495 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-23 21:57:54 +00:00
Davide Italiano
fb56e1a36f [SCCP] Update comment to reflect reality.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270413 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-23 09:34:50 +00:00
Teresa Johnson
4b05ce2d0d [ThinLTO] Add option to emit imports files for distributed backends
Summary:
Add support for emission of plaintext lists of the imported files for
each distributed backend compilation. Used for distributed build file
staging.

Invoked with new gold-plugin thinlto-emit-imports-files option, which is
only valid with thinlto-index-only (i.e. for distributed builds), or
from llvm-lto with new -thinlto-action=emitimports value.

Depends on D19556.

Reviewers: joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D19636

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269067 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-10 15:54:09 +00:00
Teresa Johnson
27af205ce1 Restore "[ThinLTO] Emit individual index files for distributed backends"
This restores commit r268627:
    Summary:
    When launching ThinLTO backends in a distributed build (currently
    supported in gold via the thinlto-index-only plugin option), emit
    an individual index file for each backend process as described here:
    http://lists.llvm.org/pipermail/llvm-dev/2016-April/098272.html

    ...

    Differential Revision: http://reviews.llvm.org/D19556

Address msan failures by avoiding std::prev on map.end(), the
theory is that this is causing issues due to some known UB problems
in __tree.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269059 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-10 13:48:23 +00:00
Davide Italiano
2d1483c124 [PM] Port Interprocedural SCCP to the new pass manager.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268684 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-05 21:05:36 +00:00
Vitaly Buka
eb80fa1253 Revert "[ThinLTO] Emit individual index files for distributed backends"
MemorySanitizer: use-of-uninitialized-value in lib/Bitcode/Writer/BitcodeWriter.cpp:364:70
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/12544/steps/check-llvm%20msan/logs/stdio

This reverts commit 0c4a898ea5.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268660 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-05 18:31:00 +00:00