[PM] Appease mingw32's auto-import DLL build with minimal tweaks.

char AnalysisBase::ID should be declared as extern and defined in one module.

llvm-svn: 262185

[PM] Provide explicit instantiation declarations and definitions for the
PassManager and AnalysisManager template specializations as well.

llvm-svn: 262128

[PM] Provide two templates for the two directionalities of analysis
manager proxies and use those rather than repeating their definition
four times.

There are real differences between the two direct

[PM] Provide two templates for the two directionalities of analysis
manager proxies and use those rather than repeating their definition
four times.

There are real differences between the two directions: outer AMs are
const and don't need to have invalidation tracked. But every proxy in
a particular direction is identical except for the analysis manager type
and the IR unit they proxy into. This makes them prime candidates for
nice templates.

I've started introducing explicit template instantiation declarations
and definitions as well because we really shouldn't be emitting all this
everywhere. I'm going to go back and add the same for the other
templates like this in a follow-up patch.

I've left the analysis manager as an opaque type rather than using two
IR units and requiring it to be an AnalysisManager template
specialization. I think its important that users retain the ability to
provide their own custom analysis management layer and provided it has
the appropriate API everything should Just Work.

llvm-svn: 262127

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[PM] Introduce CRTP mixin base classes to help define passes and
analyses in the new pass manager.

These just handle really basic stuff: turning a type name into a string
statically that is nice to

[PM] Introduce CRTP mixin base classes to help define passes and
analyses in the new pass manager.

These just handle really basic stuff: turning a type name into a string
statically that is nice to print in logs, and getting a static unique ID
for each analysis.

Sadly, the format of passes in anonymous namespaces makes using their
names in tests really annoying so I've customized the names of the no-op
passes to keep tests sane to read.

This is the first of a few simplifying refactorings for the new pass
manager that should reduce boilerplate and confusion.

llvm-svn: 262004

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[PM] Remove an overly aggressive assert now that I can actually test the
pattern that triggers it. This essentially requires an immutable
function analysis, as that will survive anything we do to inv

[PM] Remove an overly aggressive assert now that I can actually test the
pattern that triggers it. This essentially requires an immutable
function analysis, as that will survive anything we do to invalidate it.
When we have such patterns, the function analysis manager will not get
cleared between runs of the proxy.

If we actually need an assert about how things are queried, we can add
more elaborate machinery for computing it, but so far I'm not aware of
significant value provided.

Thanks to Justin Lebar for noticing this when he made a (seemingly
innocuous) change to FunctionAttrs that is enough to trigger it in one
test there. Now it is covered by a direct test of the pass manager code.

llvm-svn: 261627

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[PM] Improve the API and comments around the analysis manager proxies.

These are really handles that ensure the analyses get cleared at
appropriate places, and as such copying doesn't really make se

[PM] Improve the API and comments around the analysis manager proxies.

These are really handles that ensure the analyses get cleared at
appropriate places, and as such copying doesn't really make sense.
Instead, they should look more like unique ownership objects. Make that
the case.

Relatedly, if you create a temporary of one and move out of it
its destructor shouldn't actually clear anything. I don't think there is
any code that can trigger this currently, but it seems like a more
robust implementation.

If folks want, I can add a unittest that forces this to be exercised,
but that seems somewhat pointless -- whether a temporary is ever created
in the innards of AnalysisManager is not really something we should be
adding a reliance on, but I didn't want to leave a timebomb in the code
here.

If anyone has a cleaner way to represent this, I'm all ears, but
I wanted to assure myself that this wasn't in fact responsible for
another bug I'm chasing down (it wasn't) and figured I'd commit that.

llvm-svn: 261594

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[PM] Remove the defunt CGSCC-specific debug flag.

Even before I sunk the debug flag into the opt tool this had been made
obsolete by factoring the pass and analysis managers into a single set
of tem

[PM] Remove the defunt CGSCC-specific debug flag.

Even before I sunk the debug flag into the opt tool this had been made
obsolete by factoring the pass and analysis managers into a single set
of templates that all used the core flag. No functionality changed here.

llvm-svn: 225842

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[PM] Refactor the new pass manager to use a single template to implement
the generic functionality of the pass managers themselves.

In the new infrastructure, the pass "manager" isn't actually inter

[PM] Refactor the new pass manager to use a single template to implement
the generic functionality of the pass managers themselves.

In the new infrastructure, the pass "manager" isn't actually interesting
at all. It just pipelines a single chunk of IR through N passes. We
don't need to know anything about the IR or the passes to do this really
and we can replace the 3 implementations of the exact same functionality
with a single generic PassManager template, complementing the single
generic AnalysisManager template.

I've left typedefs in place to give convenient names to the various
obvious instantiations of the template.

With this, I think I've nuked almost all of the redundant logic in the
managers, and I think the overall design is actually simpler for having
single templates that clearly indicate there is no special logic here.
The logging is made somewhat more annoying by this change, but I don't
think the difference is worth having heavy-weight traits to help log
things.

llvm-svn: 225783

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[PM] Fold all three analysis managers into a single AnalysisManager
template.

This consolidates three copies of nearly the same core logic. It adds
"complexity" to the ModuleAnalysisManager in that

[PM] Fold all three analysis managers into a single AnalysisManager
template.

This consolidates three copies of nearly the same core logic. It adds
"complexity" to the ModuleAnalysisManager in that it makes it possible
to share a ModuleAnalysisManager across multiple modules... But it does
so by deleting *all of the code*, so I'm OK with that. This will
naturally make fixing bugs in this code much simpler, etc.

The only down side here is that we have to use 'typename' and 'this->'
in various places, and the implementation is lifted into the header.
I'll take that for the code size reduction.

The convenient names are still typedef-ed and used throughout so that
users can largely ignore this aspect of the implementation.

The follow-up change to this will do the exact same refactoring for the
PassManagers. =D

It turns out that the interesting different code is almost entirely in
the adaptors. At the end, that should be essentially all that is left.

llvm-svn: 225757

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[PM] Re-clang-format much of this code as the code has changed some and
so has clang-format. Notably, this fixes a bunch of formatting in the
CGSCC pass manager side of things that has been improved

[PM] Re-clang-format much of this code as the code has changed some and
so has clang-format. Notably, this fixes a bunch of formatting in the
CGSCC pass manager side of things that has been improved in clang-format
recently.

llvm-svn: 225743

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[PM] Fix a pretty nasty bug where the new pass manager would invalidate
passes too many time.

I think this is actually the issue that someone raised with me at the
developer's meeting and in an emai

[PM] Fix a pretty nasty bug where the new pass manager would invalidate
passes too many time.

I think this is actually the issue that someone raised with me at the
developer's meeting and in an email, but that we never really got to the
bottom of. Having all the testing utilities made it much easier to dig
down and uncover the core issue.

When a pass manager is running many passes over a single function, we
need it to invalidate the analyses between each run so that they can be
re-computed as needed. We also need to track the intersection of
preserved higher-level analyses across all the passes that we run (for
example, if there is one module analysis which all the function analyses
preserve, we want to track that and propagate it). Unfortunately, this
interacted poorly with any enclosing pass adaptor between two IR units.
It would see the intersection of preserved analyses, and need to
invalidate any other analyses, but some of the un-preserved analyses
might have already been invalidated *and recomputed*! We would fail to
propagate the fact that the analysis had already been invalidated.

The solution to this struck me as really strange at first, but the more
I thought about it, the more natural it seemed. After a nice discussion
with Duncan about it on IRC, it seemed even nicer. The idea is that
invalidating an analysis *causes* it to be preserved! Preserving the
lack of result is trivial. If it is recomputed, great. Until something
*else* invalidates it again, we're good.

The consequence of this is that the invalidate methods on the analysis
manager which operate over many passes now consume their
PreservedAnalyses object, update it to "preserve" every analysis pass to
which it delivers an invalidation (regardless of whether the pass
chooses to be removed, or handles the invalidation itself by updating
itself). Then we return this augmented set from the invalidate routine,
letting the pass manager take the result and use the intersection of
*that* across each pass run to compute the final preserved set. This
accounts for all the places where the early invalidation of an analysis
has already "preserved" it for a future run.

I've beefed up the testing and adjusted the assertions to show that we
no longer repeatedly invalidate or compute the analyses across nested
pass managers.

llvm-svn: 225333

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[PM] Add a utility pass template that synthesizes the invalidation of
a specific analysis result.

This is quite handy to test things, and will also likely be very useful
for debugging issues. You co

[PM] Add a utility pass template that synthesizes the invalidation of
a specific analysis result.

This is quite handy to test things, and will also likely be very useful
for debugging issues. You could narrow down pass validation failures by
walking these invalidate pass runs up and down the pass pipeline, etc.
I've added support to the pass pipeline parsing to be able to create one
of these for any analysis pass desired.

Just adding this class uncovered one latent bug where the
AnalysisManager CRTP base class had a hard-coded Module type rather than
using IRUnitT.

I've also added tests for invalidation and caching of analyses in
a basic way across all the pass managers. These in turn uncovered two
more bugs where we failed to correctly invalidate an analysis -- its
results were invalidated but the key for re-running the pass was never
cleared and so it was never re-run. Quite nasty. I'm very glad to debug
this here rather than with a full system.

Also, yes, the naming here is horrid. I'm going to update some of the
names to be slightly less awful shortly. But really, I've no "good"
ideas for naming. I'll be satisfied if I can get it to "not bad".

llvm-svn: 225246

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[PM] Add a collection of no-op analysis passes and switch the new pass
manager tests to use them and be significantly more comprehensive.

This, naturally, uncovered a bug where the CGSCC pass manage

[PM] Add a collection of no-op analysis passes and switch the new pass
manager tests to use them and be significantly more comprehensive.

This, naturally, uncovered a bug where the CGSCC pass manager wasn't
printing analyses when they were run.

The only remaining core manipulator is I think an invalidate pass
similar to the require pass. That'll be next. =]

llvm-svn: 225240

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[PM] Don't run the machinery of invalidating all the analysis passes
when all are being preserved.

We want to short-circuit this for a couple of reasons. One, I don't
really want passes to grow a de

[PM] Don't run the machinery of invalidating all the analysis passes
when all are being preserved.

We want to short-circuit this for a couple of reasons. One, I don't
really want passes to grow a dependency on actually receiving their
invalidate call when they've been preserved. I'm thinking about removing
this entirely. But more importantly, preserving everything is likely to
be the common case in a lot of scenarios, and it would be really good to
bypass all of the invalidation and preservation machinery there.
Avoiding calling N opaque functions to try to invalidate things that are
by definition still valid seems important. =]

This wasn't really inpsired by much other than seeing the spam in the
logging for analyses, but it seems better ot get it checked in rather
than forgetting about it.

llvm-svn: 225163

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[PM] Add names and debug logging for analysis passes to the new pass
manager.

This starts to allow us to test analyses more easily, but it's really
only the beginning. Some of the code here is still

[PM] Add names and debug logging for analysis passes to the new pass
manager.

This starts to allow us to test analyses more easily, but it's really
only the beginning. Some of the code here is still untestable without
manual changes to create analysis passes, but I wanted to factor it into
a small of chunks as possible.

Next up in order to be able to test things are, in no particular order:
- No-op analyses passes so we don't have to use real ones to exercise
the pass maneger itself.
- Automatic way of generating dummy passes that require an analysis be
run, including a variant that calls a 'print' method on a pass to make
it even easier to print out the results of an analysis.
- Dummy passes that invalidate all analyses for their IR unit so we can
test invalidation and re-runs.
- Automatic way to print each analysis pass as it is re-run.
- Automatic but optional verification of analysis passes everywhere
possible.

I'm not claiming I'll get to all of these immediately, but that's what
is in the pipeline at some stage. I'm fleshing out exactly what I need
and what to prioritize by working on converting analyses and then trying
to test the conversion. =]

llvm-svn: 225162

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[PM] Switch the new pass manager to use a reference-based API for IR
units.

This was debated back and forth a bunch, but using references is now
clearly cleaner. Of all the code written using pointe

[PM] Switch the new pass manager to use a reference-based API for IR
units.

This was debated back and forth a bunch, but using references is now
clearly cleaner. Of all the code written using pointers thus far, in
only one place did it really make more sense to have a pointer. In most
cases, this just removes immediate dereferencing from the code. I think
it is much better to get errors on null IR units earlier, potentially
at compile time, than to delay it.

Most notably, the legacy pass manager uses references for its routines
and so as more and more code works with both, the use of pointers was
likely to become really annoying. I noticed this when I ported the
domtree analysis over and wrote the entire thing with references only to
have it fail to compile. =/ It seemed better to switch now than to
delay. We can, of course, revisit this is we learn that references are
really problematic in the API.

llvm-svn: 225145

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[PM] Add a new-PM-style CGSCC pass manager using the newly added
LazyCallGraph analysis framework. Wire it up all the way through the opt
driver and add some very basic testing that we can build pass

[PM] Add a new-PM-style CGSCC pass manager using the newly added
LazyCallGraph analysis framework. Wire it up all the way through the opt
driver and add some very basic testing that we can build pass pipelines
including these components. Still a lot more to do in terms of testing
that all of this works, but the basic pieces are here.

There is a *lot* of boiler plate here. It's something I'm going to
actively look at reducing, but I don't have any immediate ideas that
don't end up making the code terribly complex in order to fold away the
boilerplate. Until I figure out something to minimize the boilerplate,
almost all of this is based on the code for the existing pass managers,
copied and heavily adjusted to suit the needs of the CGSCC pass
management layer.

The actual CG management still has a bunch of FIXMEs in it. Notably, we
don't do *any* updating of the CG as it is potentially invalidated.
I wanted to get this in place to motivate the new analysis, and add
update APIs to the analysis and the pass management layers in concert to
make sure that the *right* APIs are present.

llvm-svn: 206745

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