Commit Graph

7024 Commits

Author SHA1 Message Date
Piotr Padlewski e41beed403 [MemDep] NFC variable name change
llvm-svn: 291679
2017-01-11 16:23:54 +00:00
Hal Finkel 8a9a783f2c Make processing @llvm.assume more efficient - Add affected values to the assumption cache
Here's my second try at making @llvm.assume processing more efficient. My
previous attempt, which leveraged operand bundles, r289755, didn't end up
working: it did make assume processing more efficient but eliminating the
assumption cache made ephemeral value computation too expensive. This is a
more-targeted change. We'll keep the assumption cache, but extend it to keep a
map of affected values (i.e. values about which an assumption might provide
some information) to the corresponding assumption intrinsics. This allows
ValueTracking and LVI to find assumptions relevant to the value being queried
without scanning all assumptions in the function. The fact that ValueTracking
started doing O(number of assumptions in the function) work, for every
known-bits query, has become prohibitively expensive in some cases.

As discussed during the review, this is a pragmatic fix that, longer term, will
likely be replaced by a more-principled solution (perhaps based on an extended
SSA form).

Differential Revision: https://reviews.llvm.org/D28459

llvm-svn: 291671
2017-01-11 13:24:24 +00:00
Chandler Carruth 3bab7e1a79 [PM] Separate the LoopAnalysisManager from the LoopPassManager and move
the latter to the Transforms library.

While the loop PM uses an analysis to form the IR units, the current
plan is to have the PM itself establish and enforce both loop simplified
form and LCSSA. This would be a layering violation in the analysis
library.

Fundamentally, the idea behind the loop PM is to *transform* loops in
addition to running passes over them, so it really seemed like the most
natural place to sink this was into the transforms library.

We can't just move *everything* because we also have loop analyses that
rely on a subset of the invariants. So this patch splits the the loop
infrastructure into the analysis management that has to be part of the
analysis library, and the transform-aware pass manager.

This also required splitting the loop analyses' printer passes out to
the transforms library, which makes sense to me as running these will
transform the code into LCSSA in theory.

I haven't split the unittest though because testing one component
without the other seems nearly intractable.

Differential Revision: https://reviews.llvm.org/D28452

llvm-svn: 291662
2017-01-11 09:43:56 +00:00
Mohammed Agabaria 2c96c43388 [X86] updating TTI costs for arithmetic instructions on X86\SLM arch.
updated instructions:
pmulld, pmullw, pmulhw, mulsd, mulps, mulpd, divss, divps, divsd, divpd, addpd and subpd.

special optimization case which replaces pmulld with pmullw\pmulhw\pshuf seq. 
In case if the real operands bitwidth <= 16.

Differential Revision: https://reviews.llvm.org/D28104 

llvm-svn: 291657
2017-01-11 08:23:37 +00:00
Chandler Carruth 410eaeb064 [PM] Rewrite the loop pass manager to use a worklist and augmented run
arguments much like the CGSCC pass manager.

This is a major redesign following the pattern establish for the CGSCC layer to
support updates to the set of loops during the traversal of the loop nest and
to support invalidation of analyses.

An additional significant burden in the loop PM is that so many passes require
access to a large number of function analyses. Manually ensuring these are
cached, available, and preserved has been a long-standing burden in LLVM even
with the help of the automatic scheduling in the old pass manager. And it made
the new pass manager extremely unweildy. With this design, we can package the
common analyses up while in a function pass and make them immediately available
to all the loop passes. While in some cases this is unnecessary, I think the
simplicity afforded is worth it.

This does not (yet) address loop simplified form or LCSSA form, but those are
the next things on my radar and I have a clear plan for them.

While the patch is very large, most of it is either mechanically updating loop
passes to the new API or the new testing for the loop PM. The code for it is
reasonably compact.

I have not yet updated all of the loop passes to correctly leverage the update
mechanisms demonstrated in the unittests. I'll do that in follow-up patches
along with improved FileCheck tests for those passes that ensure things work in
more realistic scenarios. In many cases, there isn't much we can do with these
until the loop simplified form and LCSSA form are in place.

Differential Revision: https://reviews.llvm.org/D28292

llvm-svn: 291651
2017-01-11 06:23:21 +00:00
Matt Arsenault 8260666d11 InstSimplify: Refactor function to use more switches
llvm-svn: 291634
2017-01-11 00:57:54 +00:00
Matt Arsenault 1e0edbf03c InstSimplify: Eliminate fabs on known positive
llvm-svn: 291624
2017-01-11 00:33:24 +00:00
Easwaran Raman e08b139d7d Refactor inline threshold update code.
Functional change: Previously, if a callee is cold, we used ColdThreshold if it minimizes the existing threshold. This was irrespective of whether we were optimizing for minsize (-Oz) or not. But -Oz uses very low threshold to begin with and the inlining with -Oz is expected to be tuned for lowering code size, so there is no good reason to set an even lower threshold for cold callees. We now lower the threshold for cold callees only when -Oz is not used. For default values of -inlinethreshold and -inlinecold-threshold, this change has no effect and this simplifies the code.

NFC changes: Group all threshold updates that are guarded by !Caller->optForMinSize() and within that group threshold updates that require profile summary info.

Differential revision: https://reviews.llvm.org/D28369

llvm-svn: 291487
2017-01-09 21:56:26 +00:00
Xin Tong c13a8e84d1 Intrinsic::Bitreverse is safe to speculate
Summary: Intrinsic::Bitreverse is safe to speculate

Reviewers: hfinkel, mkuper, arsenm, jmolloy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28471

llvm-svn: 291456
2017-01-09 17:57:08 +00:00
Chandler Carruth 082c183f06 [PM] Teach SCEV to invalidate itself when its dependencies become
invalid.

This fixes use-after-free bugs that will arise with any interesting use
of SCEV.

I've added a dedicated test that works diligently to trigger these kinds
of bugs in the new pass manager and also checks for them explicitly as
well as triggering ASan failures when things go squirly.

llvm-svn: 291426
2017-01-09 07:44:34 +00:00
Piotr Padlewski 09ad678bc4 [MemDep] NFC walk invariant.group graph only down
Summary:
By using stripPointerCasts we can get to the root
value and then walk down the bitcast graph

Reviewers: reames

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28181

llvm-svn: 291405
2017-01-08 22:26:06 +00:00
Davide Italiano 362cc7b0fd [LCSSA] Fix some typos. NFCI.
llvm-svn: 291404
2017-01-08 22:22:09 +00:00
David Majnemer 63da0c238b [InstSimplify] Optimize away udivs in the presence of range metadata
We know that udiv %V, C can be optimized away to 0 if %V is ult C.

llvm-svn: 291296
2017-01-06 22:58:02 +00:00
David Majnemer 8c0e62f507 [InstSimplify] Optimize away urems in the presence of range metadata
We know that urem %V, C can be optimized away to %V if %V is ult C.

llvm-svn: 291282
2017-01-06 21:23:51 +00:00
Teresa Johnson 6c475a7595 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

llvm-svn: 291177
2017-01-05 21:34:18 +00:00
Teresa Johnson e27b058de3 [ThinLTO] Use DenseSet instead of SmallPtrSet for holding GUIDs
Should fix some more bot failures from r291108.
This should have been a DenseSet, since GUID is not a pointer type.
It caused some bots to fail, but for some reason I wasnt't getting a
build failure.

llvm-svn: 291115
2017-01-05 14:59:56 +00:00
Teresa Johnson 519465b993 [ThinLTO] Subsume all importing checks into a single flag
Summary:
This adds a new summary flag NotEligibleToImport that subsumes
several existing flags (NoRename, HasInlineAsmMaybeReferencingInternal
and IsNotViableToInline). It also subsumes the checking of references
on the summary that was being done during the thin link by
eligibleForImport() for each candidate. It is much more efficient to
do that checking once during the per-module summary build and record
it in the summary.

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28169

llvm-svn: 291108
2017-01-05 14:32:16 +00:00
Mohammed Agabaria 23599ba794 Currently isLikelyComplexAddressComputation tries to figure out if the given stride seems to be 'complex' and need some extra cost for address computation handling.
This code seems to be target dependent which may not be the same for all targets.
Passed the decision whether the given stride is complex or not to the target by sending stride information via SCEV to getAddressComputationCost instead of 'IsComplex'.

Specifically at X86 targets we dont see any significant address computation cost in case of the strided access in general.

Differential Revision: https://reviews.llvm.org/D27518

llvm-svn: 291106
2017-01-05 14:03:41 +00:00
Sanjay Patel 4382997a13 [ValueTracking] remove stale comments; NFC
The checks were improved with:
https://reviews.llvm.org/rL290194

llvm-svn: 290826
2017-01-02 19:04:07 +00:00
Elena Demikhovsky 21706cbd24 AVX-512 Loop Vectorizer: Cost calculation for interleave load/store patterns.
X86 target does not provide any target specific cost calculation for interleave patterns.It uses the common target-independent calculation, which gives very high numbers. As a result, the scalar version is chosen in many cases. The situation on AVX-512 is even worse, since we have 3-src shuffles that significantly reduce the cost.

In this patch I calculate the cost on AVX-512. It will allow to compare interleave pattern with gather/scatter and choose a better solution (PR31426).

* Shiffle-broadcast cost will be changed in Simon's upcoming patch.

Differential Revision: https://reviews.llvm.org/D28118

llvm-svn: 290810
2017-01-02 10:37:52 +00:00
Sanjoy Das 3bb2dbd665 Fix an issue with isGuaranteedToTransferExecutionToSuccessor
I'm not sure if this was intentional, but today
isGuaranteedToTransferExecutionToSuccessor returns true for readonly and
argmemonly calls that may throw.  This commit changes the function to
not implicitly infer nounwind this way.

Even if we eventually specify readonly calls as not throwing,
isGuaranteedToTransferExecutionToSuccessor is not the best place to
infer that.  We should instead teach FunctionAttrs or some other such
pass to tag readonly functions / calls as nounwind instead.

llvm-svn: 290794
2016-12-31 22:12:34 +00:00
Sanjoy Das 0945530d4d Avoid const_cast; NFC
llvm-svn: 290793
2016-12-31 22:12:31 +00:00
Sanjay Patel 7fd779f09f [ValueTracking] make dominator tree requirement explicit for isKnownNonNullFromDominatingCondition(); NFCI
I don't think this hole is currently exposed, but I crashed regression tests for
jump-threading and loop-vectorize after I added calls to isKnownNonNullAt() in
InstSimplify as part of trying to solve PR28430:
https://llvm.org/bugs/show_bug.cgi?id=28430

That's because they call into value tracking with a context instruction, but no
other parts of the query structure filled in.

For more background, see the discussion in:
https://reviews.llvm.org/D27855

llvm-svn: 290786
2016-12-31 17:37:01 +00:00
Philip Reames fdbb05b469 [LVI] Remove count/erase idiom in favor of checking result value of erase
Minor compile time win.  Avoids an additional O(N) scan in the case where we are removing an element and costs nothing when we aren't.

llvm-svn: 290768
2016-12-30 22:09:10 +00:00
Piotr Padlewski da36215017 [MemDep] Handle gep with zeros for invariant.group
Summary:
gep 0, 0 is equivalent to bitcast. LLVM canonicalizes it
to getelementptr because it make SROA can then handle it.

Simple case like

    void g(A &a) {
        z(a);
        if (glob)
            a.foo();
    }
    void testG() {
        A a;
        g(a);
    }

was not devirtualized with -fstrict-vtable-pointers because luck of
handling for gep 0 in Memory Dependence Analysis

Reviewers: dberlin, nlewycky, chandlerc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28126

llvm-svn: 290763
2016-12-30 18:45:07 +00:00
Philip Reames 1e48efcfc5 [LVI] Manually hoist computation from loop
Minor compile time win.  Not known to be a hot spot, just something I noticed while reading.

llvm-svn: 290759
2016-12-30 17:56:47 +00:00
Chandler Carruth 443e57e01d [PM] Teach the CGSCC's CG update utility to more carefully invalidate
analyses when we're about to break apart an SCC.

We can't wait until after breaking apart the SCC to invalidate things:
1) Which SCC do we then invalidate? All of them?
2) Even if we invalidate all of them, a newly created SCC may not have
   a proxy that will convey the invalidation to functions!

Previously we only invalidated one of the SCCs and too late. This led to
stale analyses remaining in the cache. And because the caching strategy
actually works, they would get used and chaos would ensue.

Doing invalidation early is somewhat pessimizing though if we *know*
that the SCC structure won't change. So it turns out that the design to
make the mutation API force the caller to know the *kind* of mutation in
advance was indeed 100% correct and we didn't do enough of it. So this
change also splits two cases of switching a call edge to a ref edge into
two separate APIs so that callers can clearly test for this and take the
easy path without invalidating when appropriate. This is particularly
important in this case as we expect most inlines to be between functions
in separate SCCs and so the common case is that we don't have to so
aggressively invalidate analyses.

The LCG API change in turn needed some basic cleanups and better testing
in its unittest. No interesting functionality changed there other than
more coverage of the returned sequence of SCCs.

While this seems like an obvious improvement over the current state, I'd
like to revisit the core concept of invalidating within the CG-update
layer at all. I'm wondering if we would be better served forcing the
callers to handle the invalidation beforehand in the cases that they
can handle it. An interesting example is when we want to teach the
inliner to *update and preserve* analyses. But we can cross that bridge
when we get there.

With this patch, the new pass manager an build all of the LLVM test
suite at -O3 and everything passes. =D I haven't bootstrapped yet and
I'm sure there are still plenty of bugs, but this gives a nice baseline
so I'm going to increasingly focus on fleshing out the missing
functionality, especially the bits that are just turned off right now in
order to let us establish this baseline.

llvm-svn: 290664
2016-12-28 10:34:50 +00:00
Chandler Carruth c6334579e9 [LCG] Teach the ref edge removal to handle a ref edge that is trivial
due to a call cycle.

This actually crashed the ref removal before.

I've added a unittest that covers this kind of interesting graph
structure and mutation.

llvm-svn: 290645
2016-12-28 02:24:58 +00:00
Chandler Carruth e14524ca30 [PM] Teach MemDep to invalidate its result object when its cached
analysis handles become invalid.

Add a test case for its invalidation logic.

llvm-svn: 290620
2016-12-27 19:33:04 +00:00
Chandler Carruth 56fe48b7e4 [PM] Remove a pointless optimization.
There is no need to do this within an analysis. That method shouldn't
even be reached if this predicate holds as the actual useful
optimization is in the analysis manager itself.

llvm-svn: 290614
2016-12-27 18:04:11 +00:00
Teresa Johnson e0ee5cf7c8 [ThinLTO] Fix "||" vs "|" mixup.
The effect of the bug was that we would incorrectly create summaries
for global and weak values defined in module asm (since we were
essentially testing for bit 1 which is SF_Undefined, and the
RecordStreamer ignores local undefined references). This would have
resulted in conservatively disabling importing of anything referencing
globals and weaks defined in module asm. Added these cases to the test
which now fails without this bug fix.

Fixes PR31459.

llvm-svn: 290610
2016-12-27 17:45:09 +00:00
Piotr Padlewski 2202aa9765 [MemDep] Operand visited twice bugfix
Because operand was not marked as seen it was visited twice.
It doesn't change behavior of optimization, it just saves redudant
visit, so no test changes.

llvm-svn: 290607
2016-12-27 15:06:07 +00:00
Chandler Carruth aa35167578 [PM] Teach BasicAA how to invalidate its result object.
This requires custom handling because BasicAA caches handles to other
analyses and so it needs to trigger indirect invalidation.

This fixes one of the common crashes when using the new PM in real
pipelines. I've also tweaked a regression test to check that we are at
least handling the most immediate case.

I'm going to work at re-structuring this test some to both scale better
(rather than all being in one file) and check more invalidation paths in
a follow-up commit, but I wanted to get the basic bug fix in place.

llvm-svn: 290603
2016-12-27 10:30:45 +00:00
Chandler Carruth 17c630a09c [PM] Teach the AAManager and AAResults layer (the worst offender for
inter-analysis dependencies) to use the new invalidation infrastructure.

This teaches it to invalidate itself when any of the peer function
AA results that it uses become invalid. We do this by just tracking the
originating IDs. I've kept it in a somewhat clunky API since some users
of AAResults are outside the new PM right now. We can clean this API up
if/when those users go away.

Secondly, it uses the registration on the outer analysis manager proxy
to trigger deferred invalidation when a module analysis result becomes
invalid.

I've included test cases that specifically try to trigger use-after-free
in both of these cases and they would crash or hang pretty horribly for
me even without ASan. Now they work nicely.

The `InvalidateAnalysis` utility pass required some tweaking to be
useful in this context and it still is pretty garbage. I'd like to
switch it back to the previous implementation and teach the explicit
invalidate method on the AnalysisManager to take care of correctly
triggering indirect invalidation, but I wanted to go ahead and send this
out so folks could see how all of this stuff works together in practice.
And, you know, that it does actually work. =]

Differential Revision: https://reviews.llvm.org/D27205

llvm-svn: 290595
2016-12-27 08:44:39 +00:00
Chandler Carruth ba90ae969c [PM] Introduce the facilities for registering cross-IR-unit dependencies
that require deferred invalidation.

This handles the other real-world invalidation scenario that we have
cases of: a function analysis which caches references to a module
analysis. We currently do this in the AA aggregation layer and might
well do this in other places as well.

Since this is relative rare, the technique is somewhat more cumbersome.
Analyses need to register themselves when accessing the outer analysis
manager's proxy. This proxy is already necessarily present to allow
access to the outer IR unit's analyses. By registering here we can track
and trigger invalidation when that outer analysis goes away.

To make this work we need to enhance the PreservedAnalyses
infrastructure to support a (slightly) more explicit model for "sets" of
analyses, and allow abandoning a single specific analyses even when
a set covering that analysis is preserved. That allows us to describe
the scenario of preserving all Function analyses *except* for the one
where deferred invalidation has triggered.

We also need to teach the invalidator API to support direct ID calls
instead of always going through a template to dispatch so that we can
just record the ID mapping.

I've introduced testing of all of this both for simple module<->function
cases as well as for more complex cases involving a CGSCC layer.

Much like the previous patch I've not tried to fully update the loop
pass management layer because that layer is due to be heavily reworked
to use similar techniques to the CGSCC to handle updates. As that
happens, we'll have a better testing basis for adding support like this.

Many thanks to both Justin and Sean for the extensive reviews on this to
help bring the API design and documentation into a better state.

Differential Revision: https://reviews.llvm.org/D27198

llvm-svn: 290594
2016-12-27 08:40:39 +00:00
George Burgess IV ed16024a9b [Analysis] Ignore `nobuiltin` on `allocsize` function calls.
We currently ignore the `allocsize` attribute on functions calls with
the `nobuiltin` attribute when trying to lower `@llvm.objectsize`. We
shouldn't care about `nobuiltin` here: `allocsize` is explicitly added
by the user, not inferred based on a function's symbol.

llvm-svn: 290588
2016-12-27 06:32:14 +00:00
George Burgess IV ce04489515 [Analysis] Refactor as promised in r290397.
This also makes us no longer check for `allocsize` on intrinsic calls.
This shouldn't matter, since intrinsics should provide the information
we get from `allocsize` on their own.

llvm-svn: 290585
2016-12-27 06:10:50 +00:00
Bryant Wong b5e03b61e2 [InstCombiner] Simplify lib calls to `round{,f}`
Differential Revision: https://reviews.llvm.org/D28110

llvm-svn: 290542
2016-12-26 14:29:29 +00:00
Bryant Wong a07d9b1460 [AliasAnalysis] Teach BasicAA about memcpy.
Differential Revision: https://reviews.llvm.org/D27034

llvm-svn: 290526
2016-12-25 22:42:27 +00:00
Piotr Padlewski 383edba1fd [MemDep] NFC changes
llvm-svn: 290428
2016-12-23 13:13:32 +00:00
George Burgess IV ccae43a247 Don't consider allocsize functions to be allocation functions.
This patch fixes some ASAN unittest failures on FreeBSD. See the
cfe-commits email thread for r290169 for more on those.

According to the LangRef, the allocsize attribute only tells us about
the number of bytes that exist at the memory location pointed to by the
return value of a function. It does not necessarily mean that the
function will only ever allocate. So, we need to be very careful about
treating functions with allocsize as general allocation functions. This
patch makes us fully conservative in this regard, though I suspect that
we have room to be a bit more aggressive if we want.

This has a FIXME that can be fixed by a relatively straightforward
refactor; I just wanted to keep this patch minimal. If this sticks, I'll
come back and fix it in a few days.

llvm-svn: 290397
2016-12-23 01:18:09 +00:00
Chandler Carruth 9c36c922d9 [PM] Remove now-dead extern template and explicit instantiation
declarations.

We're using a custom class here instead of the helper template, these
bits just didn't get deleted when the other bits did get deleted. This
was found by a really nice MSVC warning about explicitly instantiating
a template where some member functions aren't defined and thus can't be
instantiatied.

llvm-svn: 290327
2016-12-22 07:14:33 +00:00
Chandler Carruth e3f5064b72 [PM] Introduce a reasonable port of the main per-module pass pipeline
from the old pass manager in the new one.

I'm not trying to support (initially) the numerous options that are
currently available to customize the pass pipeline. If we end up really
wanting them, we can add them later, but I suspect many are no longer
interesting. The simplicity of omitting them will help a lot as we sort
out what the pipeline should look like in the new PM.

I've also documented to the best of my ability *why* each pass or group
of passes is used so that reading the pipeline is more helpful. In many
cases I think we have some questionable choices of ordering and I've
left FIXME comments in place so we know what to come back and revisit
going forward. But for now, I've left it as similar to the current
pipeline as I could.

Lastly, I've had to comment out several places where passes are not
ported to the new pass manager or where the loop pass infrastructure is
not yet ready. I did at least fix a few bugs in the loop pass
infrastructure uncovered by running the full pipeline, but I didn't want
to go too far in this patch -- I'll come back and re-enable these as the
infrastructure comes online. But I'd like to keep the comments in place
because I don't want to lose track of which passes need to be enabled
and where they go.

One thing that seemed like a significant API improvement was to require
that we don't build pipelines for O0. It seems to have no real benefit.

I've also switched back to returning pass managers by value as at this
API layer it feels much more natural to me for composition. But if
others disagree, I'm happy to go back to an output parameter.

I'm not 100% happy with the testing strategy currently, but it seems at
least OK. I may come back and try to refactor or otherwise improve this
in subsequent patches but I wanted to at least get a good starting point
in place.

Differential Revision: https://reviews.llvm.org/D28042

llvm-svn: 290325
2016-12-22 06:59:15 +00:00
Peter Collingbourne 1b4137a7f9 IR: Function summary representation for type tests.
Each function summary has an attached list of type identifier GUIDs. The
idea is that during the regular LTO phase we would match these GUIDs to type
identifiers defined by the regular LTO module and store the resolutions in
a top-level "type identifier summary" (which will be implemented separately).

Differential Revision: https://reviews.llvm.org/D27967

llvm-svn: 290280
2016-12-21 23:03:45 +00:00
Peter Collingbourne 35f3f7cdc7 TypeMetadataUtils: Simplify; spotted by Mehdi.
llvm-svn: 290264
2016-12-21 19:00:47 +00:00
Michael Kuperstein dd92c78669 [ConstantFolding] Fix vector GEPs harder
For vector GEPs, CastGEPIndices can end up in an infinite recursion, because
we compare the vector type to the scalar pointer type, find them different,
and then try to cast a type to itself.

Differential Revision: https://reviews.llvm.org/D28009

llvm-svn: 290260
2016-12-21 17:34:21 +00:00
Simon Pilgrim c93cd30fac [CostModel] Pass shuffle mask args with ArrayRef. NFCI.
llvm-svn: 290257
2016-12-21 15:49:01 +00:00
George Burgess IV 3f08914e7e [Analysis] Centralize objectsize lowering logic.
We're currently doing nearly the same thing for @llvm.objectsize in
three different places: two of them are missing checks for overflow,
and one of them could subtly break if InstCombine gets much smarter
about removing alloc sites. Seems like a good idea to not do that.

llvm-svn: 290214
2016-12-20 23:46:36 +00:00
Michael Zolotukhin e909a6ed35 [SCEV] Be less conservative when extending bitwidths for computing ranges.
Summary:
In getRangeForAffineAR we compute ranges for affine exprs E = A + B*C,
where ranges for A, B, and C are known. To avoid overflow, we need to
operate on a bigger bitwidth, and originally we chose 2*x+1 for this
(x being the original bitwidth). However, it is safe to use just 2*x:

A+B*C <= (2^x - 1) + (2^x - 1)*(2^x - 1) =
       =  2^x - 1 + 2^2x - 2^x - 2^x + 1 =
       = 2^2x - 2^x <= 2^2x - 1

Unnecessary extending of bitwidths results in noticeable slowdowns: ranges
perform arithmetic operations using APInt, which are much slower when bitwidths
are bigger than 64.

Reviewers: sanjoy, majnemer, chandlerc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27795

llvm-svn: 290211
2016-12-20 23:03:42 +00:00
Peter Collingbourne 0c30f089d5 IR: Eliminate non-determinism in the module summary analysis.
Also make the summary ref and call graph vectors immutable. This means
a smaller API surface and fewer places to audit for non-determinism.

Differential Revision: https://reviews.llvm.org/D27875

llvm-svn: 290200
2016-12-20 21:12:28 +00:00
Matt Arsenault cb2a7eb1aa Use MaxDepth instead of repeating its value
llvm-svn: 290194
2016-12-20 19:06:15 +00:00
George Burgess IV 45a540f72f Replace std::find_if with llvm::find_if. NFC.
llvm-svn: 290190
2016-12-20 18:46:27 +00:00
Chandler Carruth 66a9568408 [PM] Rework a loop in the CGSCC update logic to be more conservative and
clear. The current RefSCC can occur in exactly one position so we should
just enforce that and leverage the property rather than checking for it
anywhere.

This addresses review comments made on another patch.

llvm-svn: 290162
2016-12-20 03:32:17 +00:00
Chandler Carruth 1d96311447 [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

llvm-svn: 290161
2016-12-20 03:15:32 +00:00
Adrian Prantl bceaaa9643 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades and a change
to the Bitcode record for DIGlobalVariable, that makes upgrading the
old format unambiguous also for variables without DIExpressions.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 290153
2016-12-20 02:09:43 +00:00
Daniel Jasper f5123fecfe Add files I seem to have dropped in my revert (r290086).
Sorry!

llvm-svn: 290087
2016-12-19 08:32:13 +00:00
Daniel Jasper aec2fa352f Revert @llvm.assume with operator bundles (r289755-r289757)
This creates non-linear behavior in the inliner (see more details in
r289755's commit thread).

llvm-svn: 290086
2016-12-19 08:22:17 +00:00
Vedant Kumar a4bd1463c8 Retry: [BPI] Use a safer constructor to calculate branch probabilities
BPI may trigger signed overflow UB while computing branch probabilities for
cold calls or to unreachables. For example, with our current choice of weights,
we'll crash if there are >= 2^12 branches to an unreachable.

Use a safer BranchProbability constructor which is better at handling fractions
with large denominators.

Changes since the initial commit:
  - Use explicit casts to ensure that multiplication operands are 64-bit
    ints.

rdar://problem/29368161

Differential Revision: https://reviews.llvm.org/D27862

llvm-svn: 290022
2016-12-17 01:02:08 +00:00
Vedant Kumar a8871b73bb Revert "[BPI] Use a safer constructor to calculate branch probabilities"
This reverts commit r290016. It breaks this bot, even though the test
passes locally:

  http://bb.pgr.jp/builders/ninja-x64-msvc-RA-centos6/builds/32956/

AnalysisTests: /home/bb/ninja-x64-msvc-RA-centos6/llvm-project/llvm/lib/Support/BranchProbability.cpp:52: static llvm::BranchProbability llvm::BranchProbability::getBranchProbability(uint64_t, uint64_t): Assertion `Numerator <= Denominator && "Probability cannot be bigger than 1!"' failed.
llvm-svn: 290019
2016-12-17 00:19:06 +00:00
Vedant Kumar 9529643e64 [BPI] Use a safer constructor to calculate branch probabilities
BPI may trigger signed overflow UB while computing branch probabilities
for cold calls or to unreachables. For example, with our current choice
of weights, we'll crash if there are >= 2^12 branches to an unreachable.

Use a safer BranchProbability constructor which is better at handling
fractions with large denominators.

rdar://problem/29368161

Differential Revision: https://reviews.llvm.org/D27862

llvm-svn: 290016
2016-12-17 00:09:51 +00:00
Peter Collingbourne 3b8011f108 ModuleSummaryAnalysis: Remove some duplicate code. NFCI.
llvm-svn: 290003
2016-12-16 23:19:02 +00:00
Adrian Prantl 73ec065604 Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289920 (again).
I forgot to implement a Bitcode upgrade for the case where a DIGlobalVariable
has not DIExpression. Unfortunately it is not possible to safely upgrade
these variables without adding a flag to the bitcode record indicating which
version they are.
My plan of record is to roll the planned follow-up patch that adds a
unit: field to DIGlobalVariable into this patch before recomitting.
This way we only need one Bitcode upgrade for both changes (with a
version flag in the bitcode record to safely distinguish the record
formats).

Sorry for the churn!

llvm-svn: 289982
2016-12-16 19:39:01 +00:00
Adrian Prantl 74a835cda0 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 289920
2016-12-16 04:25:54 +00:00
Adrian Prantl 03c6d31a3b Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289902 while investigating bot berakage.

llvm-svn: 289906
2016-12-16 01:00:30 +00:00
Adrian Prantl ce13935776 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

llvm-svn: 289902
2016-12-16 00:36:43 +00:00
Davide Italiano 85ad36b0e0 [SimplifyLibCalls] Lower fls() to llvm.ctlz().
Differential Revision:  https://reviews.llvm.org/D14590

llvm-svn: 289894
2016-12-15 23:45:11 +00:00
Simon Pilgrim 9876ed07f6 [CostModel] Fix long standing bug with reverse shuffle mask detection
Incorrect 'undef' mask index matching meant that broadcast shuffles could be detected as reverse shuffles

llvm-svn: 289811
2016-12-15 12:12:45 +00:00
Hal Finkel f19e114237 Revert part of r289765 that is not necessary
CS.doesNotAccessMemory(ArgNo) and CS.onlyReadsMemory(ArgNo) calls
dataOperandHasImpliedAttr, so revert this part of r289765 because
it should not be necessary.

llvm-svn: 289768
2016-12-15 05:50:45 +00:00
Hal Finkel 39fed399e1 Fix argument attribute queries with bundle operands
When iterating over data operands in AA, don't make argument-attribute-specific
queries on bundle operands. Trying to fix self hosting...

llvm-svn: 289765
2016-12-15 05:09:15 +00:00
Hal Finkel 321053a7ca Fix iterator-invalidation issue
Inserting a new key into a DenseMap potentially invalidates iterators into that
map. Trying to fix an issue from r289755 triggering this assertion:

  Assertion `isHandleInSync() && "invalid iterator access!"' failed.

llvm-svn: 289757
2016-12-15 03:30:40 +00:00
Hal Finkel 3ca4a6bcf1 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...

llvm-svn: 289756
2016-12-15 03:02:15 +00:00
Hal Finkel cb9f78e1c3 Make processing @llvm.assume more efficient by using operand bundles
There was an efficiency problem with how we processed @llvm.assume in
ValueTracking (and other places). The AssumptionCache tracked all of the
assumptions in a given function. In order to find assumptions relevant to
computing known bits, etc. we searched every assumption in the function. For
ValueTracking, that means that we did O(#assumes * #values) work in InstCombine
and other passes (with a constant factor that can be quite large because we'd
repeat this search at every level of recursion of the analysis).

Several of us discussed this situation at the last developers' meeting, and
this implements the discussed solution: Make the values that an assume might
affect operands of the assume itself. To avoid exposing this detail to
frontends and passes that need not worry about it, I've used the new
operand-bundle feature to add these extra call "operands" in a way that does
not affect the intrinsic's signature. I think this solution is relatively
clean. InstCombine adds these extra operands based on what ValueTracking, LVI,
etc. will need and then those passes need only search the users of the values
under consideration. This should fix the computational-complexity problem.

At this point, no passes depend on the AssumptionCache, and so I'll remove
that as a follow-up change.

Differential Revision: https://reviews.llvm.org/D27259

llvm-svn: 289755
2016-12-15 02:53:42 +00:00
Stephan Bergmann 17c7f70362 Replace APFloatBase static fltSemantics data members with getter functions
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
2016-12-14 11:57:17 +00:00
Reid Kleckner 30422eea0f Revert "[SCEVExpand] do not hoist divisions by zero (PR30935)"
Reverts r289412. It caused an OOB PHI operand access in instcombine when
ASan is enabled. Reduction in progress.

Also reverts "[SCEVExpander] Add a test case related to r289412"

llvm-svn: 289453
2016-12-12 18:52:32 +00:00
Sebastian Pop 8c9cc8c86b [SCEVExpand] do not hoist divisions by zero (PR30935)
SCEVExpand computes the insertion point for the components of a SCEV to be code
generated.  When it comes to generating code for a division, SCEVexpand would
not be able to check (at compilation time) all the conditions necessary to avoid
a division by zero.  The patch disables hoisting of expressions containing
divisions by anything other than non-zero constants in order to avoid hoisting
these expressions past conditions that should hold before doing the division.

The patch passes check-all on x86_64-linux.

Differential Revision: https://reviews.llvm.org/D27216

llvm-svn: 289412
2016-12-12 02:52:51 +00:00
Sanjoy Das 6de678815c [TBAA] Don't generate invalid TBAA when merging nodes
Summary:
Fix a corner case in `MDNode::getMostGenericTBAA` where we can sometimes
generate invalid TBAA metadata.

Reviewers: chandlerc, hfinkel, mehdi_amini, manmanren

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D26635

llvm-svn: 289403
2016-12-11 20:07:25 +00:00
Sanjoy Das ba1bf87586 [SCEVExpander] Explicitly expand AddRec starts into loop preheader
This is NFC today, but won't be once D27216 (or an equivalent patch) is
in.

This change fixes a design problem in SCEVExpander -- it relied on a
hoisting optimization to generate correct code for add recurrences.
This meant changing the hoisting optimization to not kick in under
certain circumstances (to avoid speculating faulting instructions, say)
would break correctness.

The fix is to make the correctness requirements explicit, and have it
not rely on the hoisting optimization for correctness.

llvm-svn: 289397
2016-12-11 19:02:21 +00:00
Sanjay Patel 35289c62a8 [InstSimplify] improve function name; NFC
llvm-svn: 289332
2016-12-10 17:40:47 +00:00
Chandler Carruth 6b9816477b [PM] Support invalidation of inner analysis managers from a pass over the outer IR unit.
Summary:
This never really got implemented, and was very hard to test before
a lot of the refactoring changes to make things more robust. But now we
can test it thoroughly and cleanly, especially at the CGSCC level.

The core idea is that when an inner analysis manager proxy receives the
invalidation event for the outer IR unit, it needs to walk the inner IR
units and propagate it to the inner analysis manager for each of those
units. For example, each function in the SCC needs to get an
invalidation event when the SCC gets one.

The function / module interaction is somewhat boring here. This really
becomes interesting in the face of analysis-backed IR units. This patch
effectively handles all of the CGSCC layer's needs -- both invalidating
SCC analysis and invalidating function analysis when an SCC gets
invalidated.

However, this second aspect doesn't really handle the
LoopAnalysisManager well at this point. That one will need some change
of design in order to fully integrate, because unlike the call graph,
the entire function behind a LoopAnalysis's results can vanish out from
under us, and we won't even have a cached API to access. I'd like to try
to separate solving the loop problems into a subsequent patch though in
order to keep this more focused so I've adapted them to the API and
updated the tests that immediately fail, but I've not added the level of
testing and validation at that layer that I have at the CGSCC layer.

An important aspect of this change is that the proxy for the
FunctionAnalysisManager at the SCC pass layer doesn't work like the
other proxies for an inner IR unit as it doesn't directly manage the
FunctionAnalysisManager and invalidation or clearing of it. This would
create an ever worsening problem of dual ownership of this
responsibility, split between the module-level FAM proxy and this
SCC-level FAM proxy. Instead, this patch changes the SCC-level FAM proxy
to work in terms of the module-level proxy and defer to it to handle
much of the updates. It only does SCC-specific invalidation. This will
become more important in subsequent patches that support more complex
invalidaiton scenarios.

Reviewers: jlebar

Subscribers: mehdi_amini, mcrosier, mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D27197

llvm-svn: 289317
2016-12-10 06:34:44 +00:00
Craig Topper 107b187d2a [Analysis] Fix typo in comment. NFC
llvm-svn: 289171
2016-12-09 02:18:04 +00:00
Chandler Carruth 86f0bdf832 [LCG] Minor cleanup to the LCG walk over a function, NFC.
This just hoists the check for declarations up a layer which allows
various sets used in the walk to be smaller. Also moves the relevant
comments to match, and catches a few other cleanups in this code.

llvm-svn: 289163
2016-12-09 00:46:44 +00:00
Zia Ansari 394cef803a [InstSimplify] Add "X / 1.0" to SimplifyFDivInst.
Differential Revision: https://reviews.llvm.org/D27587

llvm-svn: 289153
2016-12-08 23:27:40 +00:00
Peter Collingbourne 235c275b20 IR, X86: Understand !absolute_symbol metadata on global variables.
Summary:
Attaching !absolute_symbol to a global variable does two things:
1) Marks it as an absolute symbol reference.
2) Specifies the value range of that symbol's address.
Teach the X86 backend to allow absolute symbols to appear in place of
immediates by extending the relocImm and mov64imm32 matchers. Start using
relocImm in more places where it is legal.

As previously proposed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/105800.html

Differential Revision: https://reviews.llvm.org/D25878

llvm-svn: 289087
2016-12-08 19:01:00 +00:00
Keno Fischer dc09119776 ConstantFolding: Don't crash when encountering vector GEP
ConstantFolding tried to cast one of the scalar indices to a vector
type. Instead, use the vector type only for the first index (which
is the only one allowed to be a vector) and use its scalar type
otherwise.

Fixes PR31250.

Reviewers: majnemer
Differential Revision: https://reviews.llvm.org/D27389

llvm-svn: 289073
2016-12-08 17:22:35 +00:00
Matt Arsenault 624e1b348c InstCombine: Fold bitcast of vector to FP scalar
llvm-svn: 288978
2016-12-07 20:56:11 +00:00
Philip Reames 02bb6a6b0b Reintroduce a check accidentally removed in 288873 to fix clang bots
I believe this is the cause of the failure, but have not been able to confirm.  Note that this is a speculative fix; I'm still waiting for a full build to finish as I synced and ended up doing a clean build which takes 20+ minutes on my machine.

llvm-svn: 288886
2016-12-07 04:48:50 +00:00
Philip Reames 29b19f0e9e Fix a warning introduced in r288874
llvm-svn: 288884
2016-12-07 04:11:22 +00:00
Chandler Carruth 5205c35075 [LCG] Add basic verification of the parent set and fix bugs it uncovers.
The existing unittests actually cover this now that we verify things.

llvm-svn: 288875
2016-12-07 01:42:40 +00:00
Philip Reames 71a496777c [LVI] Remove used return value from markX functions
llvm-svn: 288874
2016-12-07 01:03:56 +00:00
Philip Reames b47a719ac0 [LVI] Simplify mergeIn code
Remove the unused return type, use early return, use assignment operator.

llvm-svn: 288873
2016-12-07 00:54:21 +00:00
Philip Reames 864ab5c516 [LVI] Simplify obfuscated code
It doesn't matter why something is overdefined if it is...

llvm-svn: 288871
2016-12-07 00:28:28 +00:00
Sanjay Patel 5369775a84 [InstSimplify] fixed (?) to not mutate icmps
As Eli noted in the post-commit thread for r288833, the use of
swapOperands() may not be allowed in InstSimplify, so I'm 
removing those calls here pending further review. 

The swap mutates the icmp, and there doesn't appear to be precedent
for instruction mutation in InstSimplify.

I didn't actually have any tests for those cases, so I'm adding
a few here. 

llvm-svn: 288855
2016-12-06 22:09:52 +00:00
Sanjay Patel 9b1b2de348 [InstSimplify] add folds for and-of-icmps with same operands
All of these (and a few more) are already handled by InstCombine,
but we shouldn't have to wait until then to simplify these because
they're cheap to deal with here in InstSimplify.

This is the 'and' sibling of the earlier 'or' patch:
https://reviews.llvm.org/rL288833

llvm-svn: 288841
2016-12-06 19:05:46 +00:00
Sanjay Patel d0ccdb46b9 [InstSimplify] add folds for or-of-icmps with same operands
All of these (and a few more) are already handled by InstCombine,
but we shouldn't have to wait until then to simplify these because
they're cheap to deal with here in InstSimplify.

llvm-svn: 288833
2016-12-06 18:09:37 +00:00
Chandler Carruth 23a6c3f746 [LCG] Add some much needed asserts and verify runs to uncover
a hilarious bug and fix it.

We somehow were never verifying the RefSCCs newly formed when
splitting an existing one apart, and when verifying them we weren't
really checking the SCC indices mapping effectively.

If we had been, it would have been blindingly obvious that right after
putting something int `RC.SCCs` we should update `RC.SCCIndices` instead
of `SCCIndices` which we were about to clear and rebuild anyways. =[

Anyways, this is thoroughly covered by existing tests now that we
actually verify things properly.

llvm-svn: 288795
2016-12-06 10:29:23 +00:00
Chandler Carruth 8977223e55 [PM] Basic cleanups to CGSCC update code, NFC.
Just using InstIterator, simpler loop structures, and making better use
of the visit callback infrastructure.

llvm-svn: 288790
2016-12-06 10:06:06 +00:00
Philip Reames b486c49ff5 [LVI] Remove dead code in mergeIn
Integers are expressed in the lattice via constant ranges.  They can never be represented by constants or not-constants; those are reserved for non-integer types.  This code has been dead for literaly years.

llvm-svn: 288767
2016-12-06 03:34:33 +00:00
Philip Reames 05c435e3a4 [LVI] Extract a helper function
Extracting a helper function out of solveBlockValue makes the contract around the cache much easier to understand.

llvm-svn: 288766
2016-12-06 03:22:03 +00:00
Philip Reames 1baaef138d [LVI] Hide the last markX function on LVILatticeVal
This completes a small series of patches to hide the stateful updates of LVILatticeVal from the consuming code.  The only remaining stateful API is mergeIn.

llvm-svn: 288765
2016-12-06 03:01:08 +00:00
Philip Reames b29496246f [LVI] Hide a confusing internal interface
llvm-svn: 288764
2016-12-06 02:54:16 +00:00
Philip Reames 0e613f7c65 [LVI] Remove duplicate code using existing helper function
llvm-svn: 288761
2016-12-06 02:36:58 +00:00
Keno Fischer 92f377bd74 [LAA] Prevent invalid IR for loop-invariant bound in loop body
Summary:
If LAA expands a bound that is loop invariant, but not hoisted out
of the loop body, it used to use that value anyway, causing a
non-domination error, because the memcheck block is of course not
dominated by the scalar loop body. Detect this situation and expand
the SCEV expression instead.

Fixes PR31251

Reviewers: anemet
Subscribers: mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D27397

llvm-svn: 288705
2016-12-05 21:25:03 +00:00
Sanjay Patel 9d5b5e38bb [InstSimplify] add more helper functions for SimplifyICmpInst; NFCI
llvm-svn: 288589
2016-12-03 18:03:53 +00:00
Sanjay Patel dc65a27a10 [InstSimplify] add helper functions for SimplifyICmpInst; NFCI
llvm-svn: 288588
2016-12-03 17:30:22 +00:00
Peter Collingbourne 4568158c4d IR: Change PointerType to derive from Type rather than SequentialType.
As proposed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/106640.html

This is for a couple of reasons:

- Values of type PointerType are unlike the other SequentialTypes (arrays
  and vectors) in that they do not hold values of the element type. By moving
  PointerType we can unify certain aspects of how the other SequentialTypes
  are handled.
- PointerType will have no place in the SequentialType hierarchy once
  pointee types are removed, so this is a necessary step towards removing
  pointee types.

Differential Revision: https://reviews.llvm.org/D26595

llvm-svn: 288462
2016-12-02 03:05:41 +00:00
Matt Arsenault 47a4b39646 ConstantFolding: Factor code into helper function
llvm-svn: 288459
2016-12-02 02:26:02 +00:00
Peter Collingbourne ab85225be4 IR: Change the gep_type_iterator API to avoid always exposing the "current" type.
Instead, expose whether the current type is an array or a struct, if an array
what the upper bound is, and if a struct the struct type itself. This is
in preparation for a later change which will make PointerType derive from
Type rather than SequentialType.

Differential Revision: https://reviews.llvm.org/D26594

llvm-svn: 288458
2016-12-02 02:24:42 +00:00
Philip Reames 4d00af1bde Factor out common parts of LVI and Float2Int into ConstantRange [NFCI]
This just extracts out the transfer rules for constant ranges into a single shared point. As it happens, neither bit of code actually overlaps in terms of the handled operators, but with this change that could easily be tweaked in the future.

I also want to have this separated out to make experimenting with a eager value info implementation and possibly a ValueTracking-like fixed depth recursion peephole version. There's no reason all four of these can't share a common implementation which reduces the chances of bugs.

Differential Revision: https://reviews.llvm.org/D27294

llvm-svn: 288413
2016-12-01 20:08:47 +00:00
Peter Collingbourne 863cbfbeba Object: Extract a ModuleSymbolTable class from IRObjectFile.
This class represents a symbol table built from in-memory IR. It provides
access to GlobalValues and should only be used if such access is required
(e.g. in the LTO implementation). We will eventually change IRObjectFile
to read from a bitcode symbol table rather than using ModuleSymbolTable,
so it would not be able to expose the module.

Differential Revision: https://reviews.llvm.org/D27073

llvm-svn: 288319
2016-12-01 06:51:47 +00:00
Philip Reames 812476b495 Revert previous whitespace change
llvm-svn: 288312
2016-12-01 04:37:35 +00:00
Philip Reames d6f7024ae3 Test commit of whitespace to check permissions.
llvm-svn: 288311
2016-12-01 04:37:09 +00:00
Eugene Zelenko a3fe70d233 Fix some Clang-tidy and Include What You Use warnings; other minor fixes (NFC).
This preparation to remove SetVector.h dependency on SmallSet.h.

llvm-svn: 288256
2016-11-30 17:48:10 +00:00
Chandler Carruth 3ab2a5a824 [PM] Extend the explicit 'invalidate' method API on analysis results to
accept an Invalidator that allows them to invalidate themselves if their
dependencies are in turn invalidated.

Rather than recording the dependency graph ahead of time when analysis
get results from other analyses, this simply lets each result trigger
the immediate invalidation of any analyses they actually depend on. They
do this in a way that has three nice properties:

1) They don't have to handle transitive dependencies because the
   infrastructure will recurse for them.
2) The invalidate methods are still called only once. We just
   dynamically discover the necessary topological ordering, everything
   is memoized nicely.
3) The infrastructure still provides a default implementation and can
   access it so that only analyses which have dependencies need to do
   anything custom.

To make this work at all, the invalidation logic also has to defer the
deletion of the result objects themselves so that they can remain alive
until we have collected the complete set of results to invalidate.

A unittest is added here that has exactly the dependency pattern we are
concerned with. It hit the use-after-free described by Sean in much
detail in the long thread about analysis invalidation before this
change, and even in an intermediate form of this change where we failed
to defer the deletion of the result objects.

There is an important problem with doing dependency invalidation that
*isn't* solved here: we don't *enforce* that results correctly
invalidate all the analyses whose results they depend on.

I actually looked at what it would take to do that, and it isn't as hard
as I had thought but the complexity it introduces seems very likely to
outweigh the benefit. The technique would be to provide a base class for
an analysis result that would be populated with other results, and
automatically provide the invalidate method which immediately does the
correct thing. This approach has some nice pros IMO:
- Handles the case we care about and nothing else: only *results*
  that depend on other analyses trigger extra invalidation.
- Localized to the result rather than centralized in the analysis
  manager.
- Ties the storage of the reference to another result to the triggering
  of the invalidation of that analysis.
- Still supports extending invalidation in customized ways.

But the down sides here are:
- Very heavy-weight meta-programming is needed to provide this base
  class.
- Requires a pretty awful API for accessing the dependencies.

Ultimately, I fear it will not pull its weight. But we can re-evaluate
this at any point if we start discovering consistent problems where the
invalidation and dependencies get out of sync. It will fit as a clean
layer on top of the facilities in this patch that we can add if and when
we need it.

Note that I'm not really thrilled with the names for these APIs... The
name "Invalidator" seems ok but not great. The method name "invalidate"
also. In review some improvements were suggested, but they really need
*other* uses of these terms to be updated as well so I'm going to do
that in a follow-up commit.

I'm working on the actual fixes to various analyses that need to use
these, but I want to try to get tests for each of them so we don't
regress. And those changes are seperable and obvious so once this goes
in I should be able to roll them out throughout LLVM.

Many thanks to Sean, Justin, and others for help reviewing here.

Differential Revision: https://reviews.llvm.org/D23738

llvm-svn: 288077
2016-11-28 22:04:31 +00:00
Chandler Carruth 0c6efff178 [PM] Remove weird marking of invalidated analyses as "preserved".
This never made a lot of sense. They've been invalidated for one IR unit
but they aren't really preserved in any normal sense. It seemed like it
would be an elegant way of communicating to outer IR units that pass
managers and adaptors had already handled invalidation, but we've since
ended up adding sets that model this more clearly: we're now using
the 'AllAnalysesOn<IRUnitT>' set to handle cases where the trick of
"preserving" invalidated analyses didn't work.

This patch moves to rely on that technique exclusively and removes the
cumbersome API aspect of updating the preserved set when doing
invalidation. This in turn will simplify a *number* of upcoming patches.

This has a side benefit of exposing a number of places where we were
failing to mark the 'AllAnalysesOn<IRUnitT>' set as preserved. This
patch fixes those, and with those fixes shouldn't change any observable
behavior.

llvm-svn: 288023
2016-11-28 10:42:21 +00:00
Sanjay Patel 8ca30ab0c5 [InstSimplify] allow integer vector types to use computeKnownBits
Note that the non-splat lshr+lshr test folded, but that does not
work in general. Something is missing or wrong in computeKnownBits
as the non-splat shl+shl test still shows.

llvm-svn: 288005
2016-11-27 21:07:28 +00:00
Chandler Carruth dab4eae274 [PM] Change the static object whose address is used to uniquely identify
analyses to have a common type which is enforced rather than using
a char object and a `void *` type when used as an identifier.

This has a number of advantages. First, it at least helps some of the
confusion raised in Justin Lebar's code review of why `void *` was being
used everywhere by having a stronger type that connects to documentation
about this.

However, perhaps more importantly, it addresses a serious issue where
the alignment of these pointer-like identifiers was unknown. This made
it hard to use them in pointer-like data structures. We were already
dodging this in dangerous ways to create the "all analyses" entry. In
a subsequent patch I attempted to use these with TinyPtrVector and
things fell apart in a very bad way.

And it isn't just a compile time or type system issue. Worse than that,
the actual alignment of these pointer-like opaque identifiers wasn't
guaranteed to be a useful alignment as they were just characters.

This change introduces a type to use as the "key" object whose address
forms the opaque identifier. This both forces the objects to have proper
alignment, and provides type checking that we get it right everywhere.
It also makes the types somewhat less mysterious than `void *`.

We could go one step further and introduce a truly opaque pointer-like
type to return from the `ID()` static function rather than returning
`AnalysisKey *`, but that didn't seem to be a clear win so this is just
the initial change to get to a reliably typed and aligned object serving
is a key for all the analyses.

Thanks to Richard Smith and Justin Lebar for helping pick plausible
names and avoid making this refactoring many times. =] And thanks to
Sean for the super fast review!

While here, I've tried to move away from the "PassID" nomenclature
entirely as it wasn't really helping and is overloaded with old pass
manager constructs. Now we have IDs for analyses, and key objects whose
address can be used as IDs. Where possible and clear I've shortened this
to just "ID". In a few places I kept "AnalysisID" to make it clear what
was being identified.

Differential Revision: https://reviews.llvm.org/D27031

llvm-svn: 287783
2016-11-23 17:53:26 +00:00
Chandler Carruth 9eb857cb84 [LCG] Add a previously missing assert about the relationship of RefSCCs.
No intended change, everything seems to be in working order already.

llvm-svn: 287705
2016-11-22 21:40:10 +00:00
Chandler Carruth bae595b742 [LCG] Add utilities to compute parent and ascestor relationships between
SCCs.

These will be fairly expensive routines to call and might be abused in
real code, but are quite useful when debugging or in asserts and are
reasonable and well formed properties to query.

I've used one of them in an assert that was requested in a code review
here. In subsequent commits I'll start using these routines more
heavily, for example in unittests etc. But this at least gets the
groundwork in place.

Differential Revision: https://reviews.llvm.org/D25506

llvm-svn: 287682
2016-11-22 19:23:31 +00:00
Peter Collingbourne 0a4fc46321 Analysis: gep inbounds (gep inbounds (...)) is inbounds.
Differential Revision: https://reviews.llvm.org/D26441

llvm-svn: 287604
2016-11-22 01:03:40 +00:00
Marcin Koscielnicki 6af8e6c3d5 [TLI] Fix breakage introduced by D21739.
The initialize function has an early return for AMDGPU targets.  If taken,
the ShouldExtI32* initialization code will not be executed, resulting in
invalid values in the corresponding fields.  Fix this by moving the code
to the top of the function.

llvm-svn: 287570
2016-11-21 20:20:39 +00:00
Yaxun Liu 02f75f31e0 Fix known zero bits for addrspacecast.
Currently LLVM assumes that a pointer addrspacecasted to a different addr space is equivalent to trunc or zext bitwise, which is not true. For example, in amdgcn target, when a null pointer is addrspacecasted from addr space 4 to 0, its value is changed from i64 0 to i32 -1.

This patch teaches LLVM not to assume known bits of addrspacecast instruction to its operand.

Differential Revision: https://reviews.llvm.org/D26803

llvm-svn: 287545
2016-11-21 15:42:31 +00:00
Marcin Koscielnicki 5ae2c526db [TLI] Add functions determining if int parameters/returns should be zeroext/signext.
On some architectures (s390x, ppc64, sparc64, mips), C-level int is passed
as i32 signext instead of plain i32.  Likewise, unsigned int may be passed
as i32, i32 signext, or i32 zeroext depending on the platform.  Add this
information to TargetLibraryInfo, to be used whenever some LLVM pass
inserts a compiler-rt call to a function involving int parameters
or returns.

Differential Revision: http://reviews.llvm.org/D21739

llvm-svn: 287533
2016-11-21 11:57:11 +00:00
Simon Pilgrim f2fbf43704 Fix comment typos. NFC.
Identified by Pedro Giffuni in PR27636.

llvm-svn: 287490
2016-11-20 13:47:59 +00:00
Daniil Fukalov 4c3322cc84 [SCEV] limit recursion depth of CompareSCEVComplexity
Summary:
CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled loop) and runs almost infinite time.

Added cache of "equal" SCEV pairs to earlier cutoff of further estimation. Recursion depth limit was also introduced as a parameter.

Reviewers: sanjoy

Subscribers: mzolotukhin, tstellarAMD, llvm-commits

Differential Revision: https://reviews.llvm.org/D26389

llvm-svn: 287232
2016-11-17 16:07:52 +00:00
Chris Bieneman 05c279fc4b [CMake] NFC. Updating CMake dependency specifications
This patch updates a bunch of places where add_dependencies was being explicitly called to add dependencies on intrinsics_gen to instead use the DEPENDS named parameter. This cleanup is needed for a patch I'm working on to add a dependency debugging mode to the build system.

llvm-svn: 287206
2016-11-17 04:36:50 +00:00
Daniil Fukalov e870398e48 test commit, changed tab to spaces, NFC
llvm-svn: 287116
2016-11-16 16:41:40 +00:00
Kuba Brecka ddfdba3b01 [tsan] Add support for C++ exceptions into TSan (call __tsan_func_exit during unwinding), LLVM part
This adds support for TSan C++ exception handling, where we need to add extra calls to __tsan_func_exit when a function is exitted via exception mechanisms. Otherwise the shadow stack gets corrupted (leaked). This patch moves and enhances the existing implementation of EscapeEnumerator that finds all possible function exit points, and adds extra EH cleanup blocks where needed.

Differential Revision: https://reviews.llvm.org/D26177

llvm-svn: 286893
2016-11-14 21:41:13 +00:00
Teresa Johnson 3624bdf60a Restore "[ThinLTO] Prevent exporting of locals used/defined in module level asm"
This restores the rest of r286297 (part was restored in r286475).
Specifically, it restores the part requiring adding a dependency from
the Analysis to Object library (downstream use changed to correctly
model split BitReader vs BitWriter libraries).

Original description of this part of patch follows:

Module level asm may also contain defs of values. We need to prevent
export of any refs to local values defined in module level asm (e.g. a
ref in normal IR), since that also requires renaming/promotion of the
local. To do that, the summary index builder looks at all values in the
module level asm string that are not marked Weak or Global, which is
exactly the set of locals that are defined. A summary is created for
each of these local defs and flagged as NoRename.

This required adding handling to the BitcodeWriter to look at GV
declarations to see if they have a summary (rather than skipping them
all).

Finally, added an assert to IRObjectFile::CollectAsmUndefinedRefs to
ensure that an MCAsmParser is available, otherwise the module asm parse
would silently fail. Initialized the asm parser in the opt tool for use
in testing this fix.

Fixes PR30610.

llvm-svn: 286844
2016-11-14 17:12:32 +00:00
Teresa Johnson d5033a4576 [ThinLTO] Make inline assembly handling more efficient in summary
Summary:
The change in r285513 to prevent exporting of locals used in
inline asm added all locals in the llvm.used set to the reference
set of functions containing inline asm. Since these locals were marked
NoRename, this automatically prevented importing of the function.

Unfortunately, this caused an explosion in the summary reference lists
in some cases. In my particular example, it happened for a large protocol
buffer generated C++ file, where many of the generated functions
contained an inline asm call. It was exacerbated when doing a ThinLTO
PGO instrumentation build, where the PGO instrumentation included
thousands of private __profd_* values that were added to llvm.used.

We really only need to include a single llvm.used local (NoRename) value
in the reference list of a function containing inline asm to block it
being imported. However, it seems cleaner to add a flag to the summary
that explicitly describes this situation, which is what this patch does.

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D26402

llvm-svn: 286840
2016-11-14 16:40:19 +00:00
James Molloy 6df8f27c95 [InlineCost] Remove skew when calculating call costs
When calculating the cost of a call instruction we were applying a heuristic penalty as well as the cost of the instruction itself.

However, when calculating the benefit from inlining we weren't discounting the equivalent penalty for the call instruction that would be removed! This caused skew in the calculation and meant we wouldn't inline in the following, trivial case:

  int g() {
    h();
  }
  int f() {
    g();
  }

llvm-svn: 286814
2016-11-14 11:14:41 +00:00
Sanjay Patel cfcc42bdc2 [ValueTracking] recognize even more variants of smin/smax
Similar to:
https://reviews.llvm.org/rL285499
https://reviews.llvm.org/rL286318

We can't minimally expose this in IR tests because we don't have min/max intrinsics,
but the difference is visible in codegen because SelectionDAGBuilder::visitSelect() 
uses matchSelectPattern().

We're not canonicalizing these patterns in IR (yet), so I don't expect there to be any
regressions as noted here:
http://lists.llvm.org/pipermail/llvm-dev/2016-November/106868.html

llvm-svn: 286776
2016-11-13 20:04:52 +00:00
Sanjay Patel 819f096f09 [ValueTracking] move min/max matching to helper function; NFCI
llvm-svn: 286772
2016-11-13 19:30:19 +00:00
Peter Collingbourne 8dff03911c Analysis: Simplify the ScalarEvolution::getGEPExpr() interface. NFCI.
All existing callers were manually extracting information out of an existing
GEP instruction and passing it to getGEPExpr(). Simplify the interface by
changing it to take a GEPOperator instead.

llvm-svn: 286751
2016-11-13 06:59:50 +00:00
Peter Collingbourne d93620bf4d IR: Introduce inrange attribute on getelementptr indices.
If the inrange keyword is present before any index, loading from or
storing to any pointer derived from the getelementptr has undefined
behavior if the load or store would access memory outside of the bounds of
the element selected by the index marked as inrange.

This can be used, e.g. for alias analysis or to split globals at element
boundaries where beneficial.

As previously proposed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-July/102472.html

Differential Revision: https://reviews.llvm.org/D22793

llvm-svn: 286514
2016-11-10 22:34:55 +00:00
Nico Weber 85740f6b86 Revert r286437 r286438, they caused PR30976
llvm-svn: 286483
2016-11-10 17:55:41 +00:00
Adam Nemet 7da20c39ee [OptDiag] Remove non-printable chars from function name
The r283656 did this in the remark arguments.  We also need to do this
in the main function attribute as that is written to YAML as well.

llvm-svn: 286482
2016-11-10 17:47:03 +00:00
Teresa Johnson a081145ebd Restore part of "[ThinLTO] Prevent exporting of locals used/defined in module level asm"
This restores the part of r286297 that didn't require adding a
dependency from the Analysis to Object library. There are two parts
to the original fix, and this will address the handling for the case
where locals are used in module level asm.

The part that requires functionality in libObject handles local defs
in module level asm, and was reverted because our downstream build
of clang builds lib/Bitcode into a single library, and this new
dependency introduced a cycle there. I am trying to get that fixed
(see D26502), so for now that change isn't being restored

llvm-svn: 286475
2016-11-10 16:57:32 +00:00
Sanjoy Das 3d75b62ffe [SCEVExpander] Hoist unsigned divisons when safe
That is, when the divisor is a constant non-zero.

llvm-svn: 286438
2016-11-10 07:56:12 +00:00
Sanjoy Das e30a281449 [SCEVExpander] Don't hoist divisions
Fixes PR30942.

llvm-svn: 286437
2016-11-10 07:56:09 +00:00
Sanjoy Das 0ae390abce [SCEV] Eta reduce some lambdas; NFC
llvm-svn: 286429
2016-11-10 06:33:54 +00:00
Dehao Chen 38a666d6e5 Add isHotBB helper function to ProfileSummaryInfo
Summary: This will unify all BB hotness checks.

Reviewers: eraman, davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D26353

llvm-svn: 286415
2016-11-09 23:36:02 +00:00
Sanjoy Das 6b46a0d1e8 [SCEV] Refactor out a useful pattern; NFC
llvm-svn: 286386
2016-11-09 18:22:43 +00:00
Mehdi Amini b6a11a7879 Revert "[ThinLTO] Prevent exporting of locals used/defined in module level asm"
This reverts commit r286297.
Introduces a dependency from libAnalysis to libObject, which I missed
during the review.

llvm-svn: 286329
2016-11-09 01:45:13 +00:00
Sanjay Patel e104554412 [ValueTracking] recognize obfuscated variants of umin/umax
The smallest tests that expose this are codegen tests (because SelectionDAGBuilder::visitSelect() uses matchSelectPattern
to create UMAX/UMIN nodes), but it's also possible to see the effects in IR alone with folds of min/max pairs.

If these were written as unsigned compares in IR, InstCombine canonicalizes the unsigned compares to signed compares. 
Ie, running the optimizer pessimizes the codegen for this case without this patch:

define <4 x i32> @umax_vec(<4 x i32> %x) {
  %cmp = icmp ugt <4 x i32> %x, <i32 2147483647, i32 2147483647, i32 2147483647, i32 2147483647>
  %sel = select <4 x i1> %cmp, <4 x i32> %x, <4 x i32> <i32 2147483647, i32 2147483647, i32 2147483647, i32 2147483647>
  ret <4 x i32> %sel
}

$ ./opt umax.ll -S | ./llc -o - -mattr=avx

vpmaxud LCPI0_0(%rip), %xmm0, %xmm0

$ ./opt -instcombine umax.ll -S | ./llc -o - -mattr=avx

vpxor %xmm1, %xmm1, %xmm1
vpcmpgtd  %xmm0, %xmm1, %xmm1
vmovaps LCPI0_0(%rip), %xmm2    ## xmm2 = [2147483647,2147483647,2147483647,2147483647]
vblendvps %xmm1, %xmm0, %xmm2, %xmm0

Differential Revision: https://reviews.llvm.org/D26096

llvm-svn: 286318
2016-11-09 00:24:44 +00:00
Teresa Johnson 6955feebf3 [ThinLTO] Prevent exporting of locals used/defined in module level asm
Summary:
This patch uses the same approach added for inline asm in r285513 to
similarly prevent promotion/renaming of locals used or defined in module
level asm.

All static global values defined in normal IR and used in module level asm
should be included on either the llvm.used or llvm.compiler.used global.
The former were already being flagged as NoRename in the summary, and
I've simply added llvm.compiler.used values to this handling.

Module level asm may also contain defs of values. We need to prevent
export of any refs to local values defined in module level asm (e.g. a
ref in normal IR), since that also requires renaming/promotion of the
local. To do that, the summary index builder looks at all values in the
module level asm string that are not marked Weak or Global, which is
exactly the set of locals that are defined. A summary is created for
each of these local defs and flagged as NoRename.

This required adding handling to the BitcodeWriter to look at GV
declarations to see if they have a summary (rather than skipping them
all).

Finally, added an assert to IRObjectFile::CollectAsmUndefinedRefs to
ensure that an MCAsmParser is available, otherwise the module asm parse
would silently fail. Initialized the asm parser in the opt tool for use
in testing this fix.

Fixes PR30610.

Reviewers: mehdi_amini

Subscribers: johanengelen, krasin, llvm-commits

Differential Revision: https://reviews.llvm.org/D26146

llvm-svn: 286297
2016-11-08 21:53:35 +00:00
Andrew Kaylor 9604f34996 [BasicAA] Teach BasicAA to handle the inaccessiblememonly and inaccessiblemem_or_argmemonly attributes
Differential Revision: https://reviews.llvm.org/D26382

llvm-svn: 286294
2016-11-08 21:07:42 +00:00
Sanjoy Das 2582e690b7 [TBAA] Drop support for "old style" scalar TBAA tags
Summary:
We've had support for auto upgrading old style scalar TBAA access
metadata tags into the "new" struct path aware TBAA metadata for 3 years
now.  The only way to actually generate old style TBAA was explicitly
through the IRBuilder API.  I think this is a good time for dropping
support for old style scalar TBAA.

I'm not removing support for textual or bitcode upgrade -- if you have
IR with the old style scalar TBAA tags that go through the AsmParser orf
the bitcode parser before LLVM sees them, they will keep working as
usual.

Note:

  %val = load i32, i32* %ptr, !tbaa !N
  !N = < scalar tbaa node >

is equivalent to

  %val = load i32, i32* %ptr, !tbaa !M
  !N = < scalar tbaa node >
  !M = !{!N, !N, 0}

Reviewers: manmanren, chandlerc, sunfish

Subscribers: mcrosier, llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D26229

llvm-svn: 286291
2016-11-08 20:46:01 +00:00
Piotr Padlewski 01659cb9fe NFC small changes in MemDep
llvm-svn: 286260
2016-11-08 18:20:51 +00:00
Amara Emerson 0b40201e13 Adds the loop end location to the loop metadata.
This additional information can be used to improve the locations when generating remarks for loops.

Patch by Florian Hahn.

Differential Revision: https://reviews.llvm.org/D25763

llvm-svn: 286227
2016-11-08 11:18:59 +00:00
Adam Nemet b103fc52d3 [OptDiag, opt-viewer] Save callee's location and display as link
With this we get a new field in the YAML record if the value being
streamed out has a debug location.  For examples, please see the changes
to the tests.

This is then used in opt-viewer to display a link for the callee
function in the inlining remarks.

Differential Revision: https://reviews.llvm.org/D26366

llvm-svn: 286169
2016-11-07 22:41:13 +00:00