6586 Commits
Author SHA1 Message Date
David Majnemer 4a45f0871a New EH representation for MSVC compatibility
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support.  Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.

Differential Revision: http://reviews.llvm.org/D11097

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243766 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-31 17:58:14 +00:00
Adam Nemet 52aafdb50a [LDist] Filter the checks locally rather than in LAA, NFC
Before, we were passing the pointer partitions to LAA.  Now, we get all
the checks from LAA and filter out the checks within partitions in
LoopDistribution.

This effectively concludes the steps to move filtering memchecks from
LAA into its clients.  There is still some cleanup left to remove the
unused interfaces in LAA that still take PtrPartition.

(Moving this functionality to LoopDistribution also requires
needsChecking on pointers to be made public.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243613 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-30 03:29:16 +00:00
Nick Lewycky 6fc1adf9c7 Fix typo "fuction" noticed in comments in AssumptionCache.h, and also all the other files that have the same typo. All comments, no functionality change! (Merely a "fuctionality" change.)
Bonus change to remove emacs major mode marker from SystemZMachineFunctionInfo.cpp because emacs already knows it's C++ from the extension. Also fix typo "appeary" in AMDGPUMCAsmInfo.h.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243585 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-29 22:32:47 +00:00
Michael Zolotukhin 607fe5bb28 [Unroll] Handle SwitchInst properly.
Previously successor selection was simply wrong.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243545 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-29 18:10:33 +00:00
Michael Zolotukhin 815580fe7a [Unroll] Don't crash when simplified branch condition is undef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243544 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-29 18:10:29 +00:00
Sanjoy Das 44d65eac43 [Statepoints] Let patchable statepoints have a symbolic call target.
Summary:
As added initially, statepoints required their call targets to be a
constant pointer null if ``numPatchBytes`` was non-zero.  This turns out
to be a problem ergonomically, since there is no way to mark patchable
statepoints as calling a (readable) symbolic value.

This change remove the restriction of requiring ``null`` call targets
for patchable statepoints, and changes PlaceSafepoints to maintain the
symbolic call target through its transformation.

Reviewers: reames, swaroop.sridhar

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11550

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243502 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-28 23:50:30 +00:00
Michael Zolotukhin c82121e77d [Unroll] Add debug dumps to loop-unroll analyzer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243471 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-28 20:07:29 +00:00
Michael Zolotukhin 8ae1a0f789 [Unroll] Don't analyze blocks outside the loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243466 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-28 19:21:21 +00:00
Adam Nemet bd426c622e [LDist][LVer] Explicitly pass the set of memchecks to LoopVersioning, NFC
Before the patch, the checks were generated internally in
addRuntimeCheck.  Now, we use the new overloaded version of
addRuntimeCheck that takes the ready-made set of checks as a parameter.

The checks are now generated by the client (LoopDistribution) with the
new RuntimePointerChecking::generateChecks API.

Also the new printChecks API is used to print out the checks for
debugging.

This is to continue the transition over to the new model whereby clients
will get the full set of checks from LAA, filter it and then pass it to
LoopVersioning and in turn to addRuntimeCheck.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243382 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-28 05:01:53 +00:00
Sanjoy Das 477137f4d7 [LSR] Generate and use zero extends
Summary:
If a scale or a base register can be rewritten as "Zext({A,+,1})" then
LSR will now consider a formula of that form in its normal cost
computation.

Depends on D9180

Reviewers: qcolombet, atrick

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9181

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243348 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-27 23:27:51 +00:00
Pete Cooper 2deaa2924e Revert "Remove unnecessary null check. NFC."
This reverts commit r243167.

Duncan pointed out that dyn_cast can return null in these cases, so this
was an unsafe commit to make.  Sorry for the noise.

Worryingly there were no tests which fail...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243302 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-27 18:37:58 +00:00
Jingyue Wu 580991b5c9 Roll forward r243250
r243250 appeared to break clang/test/Analysis/dead-store.c on one of the build
slaves, but I couldn't reproduce this failure locally. Probably a false
positive as I saw this test was broken by r243246 or r243247 too but passed
later without people fixing anything.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243253 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-26 19:10:03 +00:00
Jingyue Wu e48b1257f1 Revert r243250
breaks tests


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243251 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-26 18:30:13 +00:00
Jingyue Wu 9f141640b5 [TTI/CostModel] improve TTI::getGEPCost and use it in CostModel::getInstructionCost
Summary:
This patch updates TargetTransformInfoImplCRTPBase::getGEPCost to consider
addressing modes. It now returns TCC_Free when the GEP can be completely folded
to an addresing mode.

I started this patch as I refactored SLSR. Function isGEPFoldable looks common
and is indeed used by some WIP of mine. So I extracted that logic to getGEPCost.

Furthermore, I noticed getGEPCost wasn't directly tested anywhere. The best
testing bed seems CostModel, but its getInstructionCost method invokes
getAddressComputationCost for GEPs which provides very coarse estimation. So
this patch also makes getInstructionCost call the updated getGEPCost for GEPs.
This change inevitably breaks some tests because the cost model changes, but
nothing looks seriously wrong -- if we believe the new cost model is the right
way to go, these tests should be updated.

This patch is not perfect yet -- the comments in some tests need to be updated.
I want to know whether this is a right approach before fixing those details.

Reviewers: chandlerc, hfinkel

Subscribers: aschwaighofer, llvm-commits, aemerson

Differential Revision: http://reviews.llvm.org/D9819

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243250 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-26 17:28:13 +00:00
Chen Li 7b0238cdc1 [LoopUnswitch] Improve loop unswitch pass to find trivial unswitch conditions more effectively
Summary:
This patch improves trivial loop unswitch. 

The current trivial loop unswitch only checks if loop header's terminator contains a trivial unswitch condition. But if the loop header only has one reachable successor (due to intentionally or unintentionally missed code simplification), we should consider the successor as part of the loop header. Therefore, instead of stopping at loop header's terminator, we should keep traversing its successors within loop until reach a *real* conditional branch or switch (whose condition can not be constant folded). This change will enable a single -loop-unswitch pass to unswitch multiple trivial conditions (unswitch one trivial condition could open opportunity to unswitch another one in the same loop), while the old implementation can unswitch only one per pass. 

Reviewers: reames, broune

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11481

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243203 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-25 03:21:06 +00:00
Lawrence Hu 5136ca2c6d Handle loop with negtive induction variable increment
This patch extend LoopReroll pass to hand the loops which
is similar to the following:

      while (len > 1) {
            sum4 += buf[len];
            sum4 += buf[len-1];
            len -= 2;
        }

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243171 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 22:01:49 +00:00
Pete Cooper b0fd31a910 Remove unnecessary null check. NFC.
Since both places which set this variable do so with dyn_cast, and not
dyn_cast_or_null, its impossible to get a nullptr here, so we can remove
the check.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243167 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 21:38:01 +00:00
Pete Cooper 9f2f1650c4 Use make_range(rbegin(), rend()) to allow foreach loops. NFC.
Instead of the pattern

for (auto I = x.rbegin(), E = x.end(); I != E; ++I)

we can use make_range to construct the reverse range and iterate using
that instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243163 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 21:13:43 +00:00
Philip Reames ec2871f730 [RewriteStatepointsForGC] Adjust naming scheme to be more stable
The names for instructions inserted were previous dependent on iteration order.  By deriving the names from the original instructions, we can avoid instability in tests without resorting to ordered traversals.  It also makes the IR mildly easier to read at large scale.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243140 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 19:01:39 +00:00
Michael Zolotukhin fc561accb7 Handle resolvable branches in complete loop unroll heuristic.
Summary:
Resolving a branch allows us to ignore blocks that won't be executed, and thus make our estimate more accurate.
This patch is intended to be applied after D10205 (though it could be applied independently).

Reviewers: chandlerc

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10206

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243084 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 01:53:04 +00:00
Philip Reames a8f6ce415b [RewriteStatepointsForGC] Fix release build warning
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243076 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 00:42:55 +00:00
Philip Reames eb902a7509 [RewriteStatepointsForGC] Use a worklist algorithm for first part of base pointer algorithm [NFC]
The new code should hopefully be equivalent to the old code; it just uses a worklist to track instructions which need to visited rather than iterating over all instructions visited each time. This should be faster, but the primary benefit is that the purpose should be more clear and the diff of adding another instruction type (forthcoming) much more obvious.

Differential Revision: http://reviews.llvm.org/D11480



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243071 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 00:02:11 +00:00
Jingyue Wu cab4b8c41b [NaryReassociate] remove redundant code
This check is already done by findClosestMatchingDominator.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243065 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-23 23:13:37 +00:00
Philip Reames e2d5247dee [RewriteStatepointsForGC] Rename PhiState to reflect that it's associated w/more than just PHIs
Today, Select instructions also have associated PhiStates.  In the near future, so will ExtractElement and SuffleVector.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243056 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-23 22:49:14 +00:00
Philip Reames 173e222715 [RewriteStatepointsForGC] Use idomatic mechanisms for debug tracing [NFC]
Deleting much of the code using trace-rewrite-statepoints and use idiomatic DEBUG statements instead.  This includes adding operator<< to a helper class.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243054 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-23 22:25:26 +00:00
Philip Reames 6c5bfdf124 [RewriteStatepointsForGC] Simplify code around meet of PhiStates [NFC]
We don't need to pass in the map from BDV to PhiStates; we can instead handle that externally and let the MeetPhiStates helper class just meet PhiStates.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243045 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-23 21:41:27 +00:00
Matt Wala 106d75d396 [Scalarizer] Fix potential for stale data in Scattered across invocations
Summary:
Scalarizer has two data structures that hold information about changes
to the function, Gathered and Scattered. These are cleared in finish()
at the end of runOnFunction() if finish() detects any changes to the
function.

However, finish() was checking for changes by only checking if
Gathered was non-empty. The function visitStore() only modifies
Scattered without touching Gathered. As a result, Scattered could have
ended up having stale data if Scalarizer only scalarized store
instructions. Since the data in Scattered is used during the execution
of the pass, this introduced dangling pointer errors.

The fix is to check whether both Scattered and Gathered are empty
before deciding what to do in finish(). This also fixes a problem
where the Function can be modified although the pass returns false.

Reviewers: rnk

Subscribers: rnk, srhines, llvm-commits

Differential Revision: http://reviews.llvm.org/D10459

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243040 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-23 20:53:46 +00:00
Chandler Carruth 8de7149b0d [GMR] Add a late run of GlobalsModRef to the main pass pipeline behind
the general GMR-in-non-LTO flag.

Without this, we have the global information during the CGSCC pipeline
for GVN and such, but don't have it available during the late loop
optimizations such as the vectorizer. Moreover, after the CGSCC pipeline
has finished we have substantially more accurate and refined call graph
information, function annotations, etc, which will make GMR even more
powerful than it is early in the pipelien.

Note that we have to play silly games with preserving AliasAnalysis
(which is now trivially preserved) in order to let a module analysis
magically be preserved into the entire function pass pipeline.
Simultaneously we have to not make GMR an immutable pass in order to be
able to re-run it and collect fresh data on the final call graph.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242999 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-23 09:34:01 +00:00
Chandler Carruth 52ab0bc417 [PM/AA] Extract the ModRef enums from the AliasAnalysis class in
preparation for de-coupling the AA implementations.

In order to do this, they had to become fake-scoped using the
traditional LLVM pattern of a leading initialism. These can't be actual
scoped enumerations because they're bitfields and thus inherently we use
them as integers.

I've also renamed the behavior enums that are specific to reasoning
about the mod/ref behavior of functions when called. This makes it more
clear that they have a very narrow domain of applicability.

I think there is a significantly cleaner API for all of this, but
I don't want to try to do really substantive changes for now, I just
want to refactor the things away from analysis groups so I'm preserving
the exact original design and just cleaning up the names, style, and
lifting out of the class.

Differential Revision: http://reviews.llvm.org/D10564

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242963 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-22 23:15:57 +00:00
Chandler Carruth f020cb2f75 [PM/AA] Remove all of the dead AliasAnalysis pointers being threaded
through APIs that are no longer necessary now that the update API has
been removed.

This will make changes to the AA interfaces significantly less
disruptive (I hope). Either way, it seems like a really nice cleanup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242882 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-22 09:52:54 +00:00
Chen Li 5015f9766b [LoopUnswitch] Code refactoring to separate trivial loop unswitch and non-trivial loop unswitch in processCurrentLoop()
Summary: The current code in LoopUnswtich::processCurrentLoop() mixes trivial loop unswitch and non-trivial loop unswitch together. It goes over all basic blocks in the loop and checks if a condition is trivial or non-trivial unswitch condition. However, trivial unswitch condition can only occur in the loop header basic block (where it controls whether or not the loop does something at all). This refactoring separate trivial loop unswitch and non-trivial loop unswitch. Before going over all basic blocks in the loop, it checks if the loop header contains a trivial unswitch condition. If so, unswitch it. Otherwise, go over all blocks like before but don't check trivial condition any more since they are not possible to be in the other blocks. This code has no functionality change.

Reviewers: meheff, reames, broune

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11276

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242873 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-22 05:26:29 +00:00
Chandler Carruth 2cf40d1ae5 [SROA] Fix a nasty pile of bugs to do with big-endian, different alloca
types and loads, loads or stores widened past the size of an alloca,
etc.

This started off with a bug report about big-endian behavior with
bitfields and loads and stores to a { i32, i24 } struct. An initial
attempt to fix this was sent for review in D10357, but that didn't
really get to the root of the problem.

The core issue was that canConvertValue and convertValue in SROA were
handling different bitwidth integers by doing a zext of the integer. It
wouldn't do a trunc though, only a zext! This would in turn lead SROA to
form an i24 load from an i24 alloca, zext it to i32, and then use it.
This would at least produce the wrong value for big-endian systems.

One of my many false starts here was to correct the computation for
big-endian systems by shifting. But this doesn't actually work because
the original code has a 64-bit store to the entire 8 bytes, and a 32-bit
load of the last 4 bytes, and because the alloc size is 8 bytes, we
can't lose that last (least significant if bigendian) byte! The real
problem here is that we're forming an i24 load in SROA which is actually
not sufficiently wide to load all of the necessary bits here. The source
has an i32 load, and SROA needs to form that as well.

The straightforward way to do this is to disable the zext logic in
canConvertValue and convertValue, forcing us to actually load all
32-bits. This seems like a really good change, but it in turn breaks
several other parts of SROA.

First in the chain of knock-on failures, we had places where we were
doing integer-widening promotion even though some of the integer loads
or stores extended *past the end* of the alloca's memory! There was even
a comment about preventing this, but it only prevented the case where
the type had a different bit size from its store size. So I added checks
to handle the cases where we actually have a widened load or store and
to avoid trying to special integer widening promotion in those cases.

Second, we actually rely on the ability to promote in the face of loads
past the end of an alloca! This is important so that we can (for
example) speculate loads around PHI nodes to do more promotion. The bits
loaded are garbage, but as long as they aren't used and the alignment is
suitable high (which it wasn't in the test case!) this is "fine". And we
can't stop promoting here, lots of things stop working well if we do. So
we need to add specific logic to handle the extension (and truncation)
case, but *only* where that extension or truncation are over bytes that
*are outside the alloca's allocated storage* and thus totally bogus to
load or store.

And of course, once we add back this correct handling of extension or
truncation, we need to correctly handle bigendian systems to avoid
re-introducing the exact bug that started us off on this chain of misery
in the first place, but this time even more subtle as it only happens
along speculated loads atop a PHI node.

I've ported an existing test for PHI speculation to the big-endian test
file and checked that we get that part correct, and I've added several
more interesting big-endian test cases that should help check that we're
getting this correct.

Fun times.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242869 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-22 03:32:42 +00:00
Nick Lewycky f17fb8d947 Fix a performance problem in memcpyopt by removing a linear scan over ranges when inserting a new range. No functionality change intended. Patch by Anthony Pesch!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242843 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-21 21:56:26 +00:00
Philip Reames 4ccee6b377 [RewriteStatepointsForGC] minor style cleanup
Use a named lambda for readability, common some code, remove a stale comments, and use llvm style variable names.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242827 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-21 19:04:38 +00:00
Philip Reames d0db907e73 [RewriteStatepointsForGC] Hoist some code out of a loop
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242808 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-21 17:18:03 +00:00
Philip Reames 5769e19790 [RewriteStatepointsForGC] Delete trivial code
A bit more code cleanup: delete some a trivial true assertion and supporting code, remove a redundant cast, and use count in assertions where feasible.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242805 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-21 16:51:17 +00:00
Philip Reames 052b66199d [RewriteStatepointsForGC] Minor code cleanup [NFC]
We can use builders to simplify part of the code and we only check for the existance of the metadata value; this enables us to delete some redundant code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242751 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-21 00:49:55 +00:00
Chandler Carruth c1a9c38190 [PM/AA] Remove the addEscapingUse update API that won't be easy to
directly model in the new PM.

This also was an incredibly brittle and expensive update API that was
never fully utilized by all the passes that claimed to preserve AA, nor
could it reasonably have been extended to all of them. Any number of
places add uses of values. If we ever wanted to reliably instrument
this, we would want a callback hook much like we have with ValueHandles,
but doing this for every use addition seems *extremely* expensive in
terms of compile time.

The only user of this update mechanism is GlobalsModRef. The idea of
using this to keep it up to date doesn't really work anyways as its
analysis requires a symmetric analysis of two different memory
locations. It would be very hard to make updates be sufficiently
rigorous to *guarantee* symmetric analysis in this way, and it pretty
certainly isn't true today.

However, folks have been using GMR with this update for a long time and
seem to not be hitting the issues. The reported issue that the update
hook fixes isn't even a problem any more as other changes to
GetUnderlyingObject worked around it, and that issue stemmed from *many*
years ago. As a consequence, a prior patch provided a flag to control
the unsafe behavior of GMR, and this patch removes the update mechanism
that has questionable compile-time tradeoffs and is causing problems
with moving to the new pass manager. Note the lack of test updates --
not one test in tree actually requires this update, even for a contrived
case.

All of this was extensively discussed on the dev list, this patch will
just enact what that discussion decides on. I'm sending it for review in
part to show what I'm planning, and in part to show the *amazing* amount
of work this avoids. Every call to the AA here is something like three
to six indirect function calls, which in the non-LTO pipeline never do
any work! =[

Differential Revision: http://reviews.llvm.org/D11214

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242605 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-18 03:26:46 +00:00
Cong Hou 8770f7af5f Create a wrapper pass for BranchProbabilityInfo.
This new wrapper pass is useful when we want to do branch probability analysis conditionally (e.g. only in PGO mode) but don't want to add one more pass dependence.

http://reviews.llvm.org/D11241



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242349 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-15 22:48:29 +00:00
Chen Li c2fa6d64b4 [LoopUnswitch] Add an else clause to IsTrivialUnswitchCondition() when checking HeaderTerm instruction type
Summary:
This is a trivial code change with no functionality effect. 

When LoopUnswitch determines trivial unswitch condition, it checks whether the loop header's terminator instruction is a branch instruction or switch instruction since trivial unswitch condition can only apply to these two instruction types. The current code does not fail the check directly on other instruction types, but check the nullness of LoopExitBB variable instead. The added else clause makes the check fail immediately on other instruction types and makes the code more obvious.  

Reviewers: reames

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11239

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242345 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-15 22:41:13 +00:00
Michael Zolotukhin 67ee52cf04 [LoopUnrolling] Handle cast instructions.
During estimation of unrolling effect we should be able to propagate
constants through casts.

Differential Revision: http://reviews.llvm.org/D10207

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242257 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-15 00:19:51 +00:00
Adam Nemet 00b675df73 [LAA] Introduce RuntimePointerChecking::PointerInfo, NFC
Turn this structure-of-arrays (i.e. the various pointer attributes) into
array-of-structures.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242219 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 22:32:50 +00:00
Adam Nemet 944e082905 [LAA] Lift RuntimePointerCheck out of LoopAccessInfo, NFC
I am planning to add more nested classes inside RuntimePointerCheck so
all these triple-nesting would be hard to follow.

Also rename it to RuntimePointerChecking (i.e. append 'ing').

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242218 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 22:32:44 +00:00
Tim Northover 0d71b6afcb GVN: use a static array instead of regenerating it each time. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242202 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 21:14:58 +00:00
Tim Northover 0e34491fef GVN: tolerate an instruction being replaced without existing in the leaderboard
Sometimes an incidentally created instruction can duplicate a Value used
elsewhere. It then often doesn't end up in the leader table. If it's later
removed, we attempt to remove it from the leader table and segfault.

Instead we should just ignore the removal request, which won't cause any
problems. The reverse situation, where the original instruction is replaced by
the new one (which you might think could leave the leader table empty) cannot
occur, because the incidental instruction will never be found in the first
place.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242199 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 21:03:18 +00:00
David Majnemer 2a27389edc [SROA] Don't de-atomic volatile loads and stores
Volatile loads and stores are made visible in global state regardless of
what memory is involved.  It is not correct to disregard the ordering
and synchronization scope because it is possible to synchronize with
memory operations performed by hardware.

This partially addresses PR23737.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242126 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 06:19:58 +00:00
Pete Cooper 71a4b301fd Loop idiom recognizer was replacing too many uses of popcount.
When spotting that a loop can use ctpop, we were incorrectly replacing all uses of a value with a value derived from ctpop.

The bug here was exposed because we were replacing a use prior to the ctpop with the ctpop value and so we have a use before def, i.e., we changed

 %tobool.5 = icmp ne i32 %num, 0
 store i1 %tobool.5, i1* %ptr
 br i1 %tobool.5, label %for.body.lr.ph, label %for.end

to

 store i1 %1, i1* %ptr
 %0 = call i32 @llvm.ctpop.i32(i32 %num)
 %1 = icmp ne i32 %0, 0
 br i1 %1, label %for.body.lr.ph, label %for.end

Even if we inserted the ctpop so that it dominates the store here, that would still be incorrect.  The store doesn’t want the result of ctpop.

The fix is very simple, and involves replacing only the branch condition with the ctpop instead of all uses.

Reviewed by Hal Finkel.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242068 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 21:25:33 +00:00
Mark Heffernan 8a9e01d606 Enable runtime unrolling with unroll pragma metadata
Enable runtime unrolling for loops with unroll count metadata ("#pragma unroll N")
and a runtime trip count. Also, do not unroll loops with unroll full metadata if the
loop has a runtime loop count. Previously, such loops would be unrolled with a
very large threshold (pragma-unroll-threshold) if runtime unrolled happened to be
enabled resulting in a very large (and likely unwise) unroll factor.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242047 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 18:26:27 +00:00
Benjamin Kramer ed5546e50b Avoid using Loop::getSubLoopsVector.
Passes should never modify it, just use the const version. While there
reduce copying in LoopInterchange. No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242041 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 17:21:14 +00:00
David Majnemer a1b821fac9 [LICM] Don't try to sink values out of loops without any exits
There is no suitable basic block to sink instructions in loops without
exits.  The only way an instruction in a loop without exits can be used
is as an incoming value to a PHI.  In such cases, the incoming block for
the corresponding value is unreachable.

This fixes PR24013.

Differential Revision: http://reviews.llvm.org/D10903

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241987 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-12 03:53:05 +00:00