6079 Commits

Author SHA1 Message Date
James Molloy
6a8908e979 [GlobalsAA] Partially back out r248576
See PR25822 for a more full summary, but we were conflating the concepts of "capture" and "escape". We were proving nocapture and using that proof to infer noescape, which is not true. Escaped-ness is a function-local property - as soon as a value is used in a call argument it escapes. Capturedness is a related but distinct property. It implies a *temporally limited* escape. Consider:

  static int a;
  int b;
  int g(int * nocapture arg);
  int f() {
    a = 2;  // Even though a escapes to g, it is not captured so can be treated as non-escaping here.
    g(&a);  // But here it must be treated as escaping.
    g(&b);  // Now that g(&a) has returned we know it was not captured so we can treat it as non-escaping again.
  }

The original commit did not sufficiently understand this nuance and so caused PR25822 and PR26046.

r248576 included both a performance improvement (which has been backed out) and a related conformance fix (which has been kept along with its testcase).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257058 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-07 13:33:28 +00:00
Weiming Zhao
b85410e4f3 Recommit r256952 "Filtering IR printing for print-after-all/print-before-all"
Fix lit test fail due to outputting an extra line.

Differential Revision: http://reviews.llvm.org/D15776



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256987 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-06 22:55:03 +00:00
Weiming Zhao
4357b8d663 Revert r256952 due to lit test fails.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256954 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-06 18:31:44 +00:00
Weiming Zhao
79d91e563f Filtering IR printing for print-after-all/print-before-all
Summary:
This patch implements "-print-funcs" option to support function filtering for IR printing like -print-after-all, -print-before etc.
Examples:
  -print-after-all -print-funcs=foo,bar

Reviewers: mcrosier, joker.eph

Subscribers: tejohnson, joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D15776

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256952 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-06 18:20:25 +00:00
Philip Reames
9a7a90005c [BasicAA] Extract WriteOnly predicate on parameters [NFC]
Since writeonly is the only missing attribute and special case left for the memset/memcpy family of intrinsics, rearrange the code to make that much more clear.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256949 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-06 18:10:35 +00:00
Amaury Sechet
c9f1b312c4 Revert "GlobalsAA: Take advantage of ArgMemOnly, InaccessibleMemOnly and InaccessibleMemOrArgMemOnly attributes"
Summary:
This reverts commit 5a9e526f29cf8510ab5c3d566fbdcf47ac24e1e9.

As per discussion in D15665

This also add a test case so that regression introduced by that diff are not reintroduced.

Reviewers: vaivaswatha, jmolloy, hfinkel, reames

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15919

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256932 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-06 13:23:52 +00:00
Philip Reames
ef80e8aad9 [BasicAA] Remove special casing of memset_pattern16 in favor of generic attribute inference
Most of the properties of memset_pattern16 can be now covered by the generic attributes and inferred by InferFunctionAttrs.  The only exceptions are:
- We don't yet have a writeonly attribute for the first argument.
- We don't have an attribute for modeling the access size facts encoded in MemoryLocation.cpp.  

Differential Revision: http://reviews.llvm.org/D15879



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256911 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-06 04:53:16 +00:00
Philip Reames
719759b2fa [BasicAA] Delete dead code related to memset/memcpy/memmove intrinsics [NFCI]
We only need to describe the writeonly property of one of the arguments. All of the rest of the semantics are nicely described by existing attributes in Intrinsics.td.

Differential Revision: http://reviews.llvm.org/D15880



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256910 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-06 04:43:03 +00:00
Manuel Jacob
397864c712 [Statepoints] Refactor GCRelocateOperands into an intrinsic wrapper. NFC.
Summary:
This commit renames GCRelocateOperands to GCRelocateInst and makes it an
intrinsic wrapper, similar to e.g. MemCpyInst.  Also, all users of
GCRelocateOperands were changed to use the new intrinsic wrapper instead.

Reviewers: sanjoy, reames

Subscribers: reames, sanjoy, llvm-commits

Differential Revision: http://reviews.llvm.org/D15762

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256811 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-05 04:03:00 +00:00
Philip Reames
1aeaf6cd63 [MDA] Don't be quite as conservative for noalias functions
If we encounter a noalias call that alias analysis can't analyse, we can fall down into the generic call handling rather than giving up entirely. I noticed this while reading through the code for another purpose.

I can't seem to write a test case which changes; that sorta makes sense given any test case would have to be an inconsistency in AA. Suggestions welcome.

Differential Revision: http://reviews.llvm.org/D15825



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256802 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-05 00:49:14 +00:00
Philip Reames
e14c161b0e [MemoryBuiltins] Remove isOperatorNewLike by consolidating non-null inference handling
This patch removes the isOperatorNewLike predicate since it was only being used to establish a non-null return value and we have attributes specifically for that purpose with generic handling. To keep approximate the same behaviour for existing frontends, I added the various operator new like (i.e. instances of operator new) to InferFunctionAttrs. It's not really clear to me why this isn't handled in Clang, but I didn't want to break existing code and any subtle assumptions it might have.

Once this patch is in, I'm going to start separating the isAllocLike family of predicates. These appear to be being used for a mixture of things which should be more clearly separated and documented. Today, they're being used to indicate (at least) aliasing facts, CSE-ability, and default values from an allocation site.

Differential Revision: http://reviews.llvm.org/D15820



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256787 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-04 22:49:23 +00:00
Nick Lewycky
9e83b9f4a1 Fix comment in typo. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256761 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-04 16:44:44 +00:00
Chandler Carruth
ab99ec2ce7 Fix a horrible infloop in value tracking in the face of dead code.
Amazingly, we just never triggered this without:
1) Moving code around for MetadataTracking so that a certain *different*
   amount of inlining occurs in the per-TU compile step.
2) Then you LTO opt or clang with a bootstrap, and get inlining, loop
   opts, and GVN line up everything *just* right.

I don't really know how we didn't hit this before. We really need to be
fuzz testing stuff, it shouldn't be hard to trigger. I'm working on
crafting a reduced nice test case, and will submit that when I have it,
but I want to get LTO build bots going again.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256735 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-04 07:23:12 +00:00
Craig Topper
2921ff9ffc Use std::is_sorted and std::none_of instead of manual loops. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256719 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-03 19:43:40 +00:00
Sanjay Patel
08e3bf995e [ValueTracking] fix bug computing isKnownToBeAPowerOfTwo() with arithmetic shift right (PR25900)
This is a fix for:
https://llvm.org/bugs/show_bug.cgi?id=25900

If we think that an arithmetic right shift of a power of two is always a power of two, 
an sdiv gets wrongly converted to udiv.

Differential Revision: http://reviews.llvm.org/D15827



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256655 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-30 22:40:52 +00:00
Philip Reames
d70fde56aa [MemoryBuiltins] Delete dead code [NFC]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256565 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-29 17:04:43 +00:00
Easwaran Raman
0651a407f6 Refactor inline costs analysis by removing the InlineCostAnalysis class
InlineCostAnalysis is an analysis pass without any need for it to be one.
Once it stops being an analysis pass, it doesn't maintain any useful state
and the member functions inside can be made free functions. NFC.

Differential Revision: http://reviews.llvm.org/D15701



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256521 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-28 20:28:19 +00:00
Elena Demikhovsky
84f6badccc Implemented cost model for masked gather and scatter operations
The cost is calculated for all X86 targets. When gather/scatter instruction
is not supported we calculate the cost of scalar sequence.

Differential revision: http://reviews.llvm.org/D15677



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256519 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-28 20:10:59 +00:00
Chandler Carruth
b3028527cb [lcg] Fix a few more formatting goofs found by clang-format. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256480 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-28 01:54:20 +00:00
Chandler Carruth
5276bfeab1 Add a missing const qualifier on the context instruction. This somehow
has always been missing. =/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256371 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-24 09:08:08 +00:00
JF Bastien
d7f93b3cb5 Fix SCEV r256338.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256344 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-23 18:18:53 +00:00
Sanjoy Das
32b3dea698 [SCEV] Fix getLoopBackedgeTakenCounts
The way `getLoopBackedgeTakenCounts` is written right now isn't
correct. It will try to compute and store the BE counts of a Loop
 #{child loop} number of times (which may be zero).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256338 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-23 17:48:14 +00:00
David Majnemer
07a42297a7 [OperandBundles] Have GlobalsModRef play nice with operand bundles
A call site's use of a Value might not correspond to an argument
operand but to a bundle operand.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256329 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-23 09:58:46 +00:00
Akira Hatanaka
37de9d09f1 Provide a way to specify inliner's attribute compatibility and merging.
This reapplies r256277 with two changes:

- In emitFnAttrCompatCheck, change FuncName's type to std::string to fix
  a use-after-free bug.
- Remove an unnecessary install-local target in lib/IR/Makefile. 

Original commit message for r252949:

Provide a way to specify inliner's attribute compatibility and merging
rules using table-gen. NFC.

This commit adds new classes CompatRule and MergeRule to Attributes.td,
which are used to generate code to check attribute compatibility and
merge attributes of the caller and callee.

rdar://problem/19836465


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256304 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-22 23:57:37 +00:00
Cong Hou
12ba7a9064 [BPI] Fix two potential divide-by-zero operations that are introduced in r256263.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256303 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-22 23:45:55 +00:00
Akira Hatanaka
4a8b38c05b Revert r256277 and r256279.
Some of the bots failed again.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256280 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-22 20:29:09 +00:00
Akira Hatanaka
a4912f5755 Provide a way to specify inliner's attribute compatibility and merging.
This reapplies r252990 and r252949. I've added member function getKind
to the Attr classes which returns the enum or string of the attribute.

Original commit message for r252949:

Provide a way to specify inliner's attribute compatibility and merging
rules using table-gen. NFC.

This commit adds new classes CompatRule and MergeRule to Attributes.td,
which are used to generate code to check attribute compatibility and
merge attributes of the caller and callee.

rdar://problem/19836465


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256277 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-22 20:00:05 +00:00
Cong Hou
40288f7238 [BPI] Replace weights by probabilities in BPI.
This patch removes all weight-related interfaces from BPI and replace
them by probability versions. With this patch, we won't use edge weight
anymore in either IR or MC passes. Edge probabilitiy is a better
representation in terms of CFG update and validation.


Differential revision: http://reviews.llvm.org/D15519 




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256263 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-22 18:56:14 +00:00
Jun Bum Lim
e7f0062250 Enhance BranchProbabilityInfo::calcUnreachableHeuristics for InvokeInst
This is recommit of r256028 with minor fixes in unittests:
  CodeGen/Mips/eh.ll
  CodeGen/Mips/insn-zero-size-bb.ll

Original commit message:

When identifying blocks post-dominated by an unreachable-terminated block
in BranchProbabilityInfo, consider only the edge to the normal destination
block if the terminator is InvokeInst and let calcInvokeHeuristics() decide
edge weights for the InvokeInst.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256202 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-21 22:00:51 +00:00
Michael Zolotukhin
4c1d77039a [ValueTracking] Properly handle non-sized types in isAligned function.
Reviewers: apilipenko, reames, sanjoy, hfinkel

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15597

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256192 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-21 20:38:18 +00:00
Jingyue Wu
509e2e953b [DivergenceAnalysis] fix a bug in computing influence regions
Fixes PR25864



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256036 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-18 21:44:26 +00:00
Rafael Espindola
a4c2a53b4b Revert "Enhance BranchProbabilityInfo::calcUnreachableHeuristics for InvokeInst"
This reverts commit r256028.

It broke:

    LLVM :: CodeGen/Mips/eh.ll
    LLVM :: CodeGen/Mips/insn-zero-size-bb.ll

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256032 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-18 21:23:32 +00:00
Jun Bum Lim
ec63ff81dd Enhance BranchProbabilityInfo::calcUnreachableHeuristics for InvokeInst
When identifying blocks post-dominated by an unreachable-terminated block
in BranchProbabilityInfo, consider only the edge to the normal destination
block if the terminator is InvokeInst and let calcInvokeHeuristics() decide
edge weights for the InvokeInst.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256028 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-18 20:53:47 +00:00
Andrew Kaylor
81cf167ed6 [WinEH] Update LCSSA to handle catchswitch with handlers inside and outside a loop
Differential Revision: http://reviews.llvm.org/D15630



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256005 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-18 18:12:35 +00:00
Vaivaswatha Nagaraj
5a9e526f29 GlobalsAA: Take advantage of ArgMemOnly, InaccessibleMemOnly and InaccessibleMemOrArgMemOnly attributes
Summary:
1. Modify AnalyzeCallGraph() to retain function info for external functions
if the function has [InaccessibleMemOr]ArgMemOnly flags.
2. When analyzing the use of a global is function parameter at a call site,
mark the callee also as modifying the global appropriately.
3. Add additional test cases.

Depends on D15499

Reviewers: hfinkel, jmolloy

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15605

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255994 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-18 11:02:52 +00:00
Sanjoy Das
4b892417a6 [SCEV] Add and use SCEVConstant::getAPInt; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255921 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-17 20:28:46 +00:00
Andy Gibbs
02fd5dfa7c Revert r254592 (virtual dtor in SCEVPredicate).
Clang has better diagnostics in this case.  It is not necessary therefore
to change the destructor to avoid what is effectively an invalid warning
in gcc.  Instead, better handle the warning flags given to the compiler.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255905 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-17 16:43:53 +00:00
Justin Bogner
50776d0d9e LPM: Make callers of LPM.deleteLoopFromQueue update LoopInfo directly. NFC
As of r255720, the loop pass manager will DTRT when passes update the
loop info for removed loops, so they no longer need to reach into
LPPassManager APIs to do this kind of transformation. This change very
nearly removes the need for the LPPassManager to even be passed into
loop passes - the only remaining pass that uses the LPM argument is
LoopUnswitch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255797 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-16 18:40:20 +00:00
Justin Bogner
53252a19a9 Fix typo in r255720
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255724 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-16 00:17:34 +00:00
Justin Bogner
6da3c1a607 LPM: Simplify how passes mark loops for deletion. NFC
When a pass removes a loop it currently has to reach up into the
LPPassManager's internals to update the state of the iteration over
loops. This reverse dependency results in a pretty awkward interplay
of the LPPassManager and its Passes.

Here, we change this to instead keep track of when a loop has become
"unlooped" in the Loop objects themselves, then the LPPassManager can
check this and manipulate its own state directly. This opens the door
to allow most of the loop passes to work without a backreference to
the LPPassManager.

I've kept passes calling the LPPassManager::deleteLoopFromQueue API
now so I could put an assert in to prove that this is NFC, but a later
pass will update passes just to preserve the LoopInfo directly and
stop referencing the LPPassManager completely.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255720 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-16 00:01:02 +00:00
Nicolai Hahnle
44c3e26b95 AMDGPU: mark ldexp LibCalls as unavailable
Summary:
The LibCallSimplifier will turn llvm.exp2.* intrinsics into ldexp* libcalls
which do not make sense with the AMDGPU backend.

In the long run, we'll want an llvm.ldexp.* intrinsic to properly make use of
this optimization, but this works around the problem for now.

See also: http://reviews.llvm.org/D14327 (suggested llvm.ldexp.* implementation)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92709

Reviewers: arsenm, tstellarAMD

Differential Revision: http://reviews.llvm.org/D14990

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255658 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-15 17:24:15 +00:00
David Majnemer
868145efb0 [IR] Remove terminatepad
It turns out that terminatepad gives little benefit over a cleanuppad
which calls the termination function.  This is not sufficient to
implement fully generic filters but MSVC doesn't support them which
makes terminatepad a little over-designed.

Depends on D15478.

Differential Revision: http://reviews.llvm.org/D15479

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255522 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-14 18:34:23 +00:00
David Majnemer
b0b46be58a Try to appease a buildbot
The builder complains thusly:
error C2027: use of undefined type 'llvm::raw_ostream'

Try to make it happy by including raw_ostream.h

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255425 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-12 05:53:20 +00:00
David Majnemer
8cec2f2816 [IR] Reformulate LLVM's EH funclet IR
While we have successfully implemented a funclet-oriented EH scheme on
top of LLVM IR, our scheme has some notable deficiencies:
- catchendpad and cleanupendpad are necessary in the current design
  but they are difficult to explain to others, even to seasoned LLVM
  experts.
- catchendpad and cleanupendpad are optimization barriers.  They cannot
  be split and force all potentially throwing call-sites to be invokes.
  This has a noticable effect on the quality of our code generation.
- catchpad, while similar in some aspects to invoke, is fairly awkward.
  It is unsplittable, starts a funclet, and has control flow to other
  funclets.
- The nesting relationship between funclets is currently a property of
  control flow edges.  Because of this, we are forced to carefully
  analyze the flow graph to see if there might potentially exist illegal
  nesting among funclets.  While we have logic to clone funclets when
  they are illegally nested, it would be nicer if we had a
  representation which forbade them upfront.

Let's clean this up a bit by doing the following:
- Instead, make catchpad more like cleanuppad and landingpad: no control
  flow, just a bunch of simple operands;  catchpad would be splittable.
- Introduce catchswitch, a control flow instruction designed to model
  the constraints of funclet oriented EH.
- Make funclet scoping explicit by having funclet instructions consume
  the token produced by the funclet which contains them.
- Remove catchendpad and cleanupendpad.  Their presence can be inferred
  implicitly using coloring information.

N.B.  The state numbering code for the CLR has been updated but the
veracity of it's output cannot be spoken for.  An expert should take a
look to make sure the results are reasonable.

Reviewers: rnk, JosephTremoulet, andrew.w.kaylor

Differential Revision: http://reviews.llvm.org/D15139

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255422 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-12 05:38:55 +00:00
Akira Hatanaka
283d7ebfd0 [LazyValueInfo] Stop inserting overdefined values into ValueCache to
reduce memory usage.

Previously, LazyValueInfoCache inserted overdefined lattice values into
both ValueCache and OverDefinedCache. This wasn't necessary and was
causing LazyValueInfo to use an excessive amount of memory in some cases.

This patch changes LazyValueInfoCache to insert overdefined values only
into OverDefinedCache. The memory usage decreases by 70 to 75% when one
of the files in llvm is compiled.

rdar://problem/11388615

Differential revision: http://reviews.llvm.org/D15391


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255320 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-11 00:49:47 +00:00
Silviu Baranga
90f6cd579a Re-commit r255115, with the PredicatedScalarEvolution class moved to
ScalarEvolution.h, in order to avoid cyclic dependencies between the Transform
and Analysis modules:

[LV][LAA] Add a layer over SCEV to apply run-time checked knowledge on SCEV expressions

Summary:
This change creates a layer over ScalarEvolution for LAA and LV, and centralizes the
usage of SCEV predicates. The SCEVPredicatedLayer takes the statically deduced knowledge
by ScalarEvolution and applies the knowledge from the SCEV predicates. The end goal is
that both LAA and LV should use this interface everywhere.

This also solves a problem involving the result of SCEV expression rewritting when
the predicate changes. Suppose we have the expression (sext {a,+,b}) and two predicates
  P1: {a,+,b} has nsw
  P2: b = 1.

Applying P1 and then P2 gives us {a,+,1}, while applying P2 and the P1 gives us
sext({a,+,1}) (the AddRec expression was changed by P2 so P1 no longer applies).
The SCEVPredicatedLayer maintains the order of transformations by feeding back
the results of previous transformations into new transformations, and therefore
avoiding this issue.

The SCEVPredicatedLayer maintains a cache to remember the results of previous
SCEV rewritting results. This also has the benefit of reducing the overall number
of expression rewrites.

Reviewers: mzolotukhin, anemet

Subscribers: jmolloy, sanjoy, llvm-commits

Differential Revision: http://reviews.llvm.org/D14296



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255122 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-09 16:06:28 +00:00
Silviu Baranga
bdd73bcbd7 Revert r255115 until we figure out how to fix the bot failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255117 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-09 15:25:28 +00:00
Silviu Baranga
69c30d5b6c [LV][LAA] Add a layer over SCEV to apply run-time checked knowledge on SCEV expressions
Summary:
This change creates a layer over ScalarEvolution for LAA and LV, and centralizes the
usage of SCEV predicates. The SCEVPredicatedLayer takes the statically deduced knowledge
by ScalarEvolution and applies the knowledge from the SCEV predicates. The end goal is
that both LAA and LV should use this interface everywhere.

This also solves a problem involving the result of SCEV expression rewritting when
the predicate changes. Suppose we have the expression (sext {a,+,b}) and two predicates
  P1: {a,+,b} has nsw
  P2: b = 1.

Applying P1 and then P2 gives us {a,+,1}, while applying P2 and the P1 gives us
sext({a,+,1}) (the AddRec expression was changed by P2 so P1 no longer applies).
The SCEVPredicatedLayer maintains the order of transformations by feeding back
the results of previous transformations into new transformations, and therefore
avoiding this issue.

The SCEVPredicatedLayer maintains a cache to remember the results of previous
SCEV rewritting results. This also has the benefit of reducing the overall number
of expression rewrites.

Reviewers: mzolotukhin, anemet

Subscribers: jmolloy, sanjoy, llvm-commits

Differential Revision: http://reviews.llvm.org/D14296

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255115 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-09 15:03:52 +00:00
Sanjoy Das
8f28b0e1d8 [SCEV] Use for-each; NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255069 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-08 22:53:36 +00:00
Sanjoy Das
711641834a [SCEV] Move some struct declarations inside functions; NFC
Reduces the scope over which the struct is visible, making its usages
obvious.  I did not move structs in cases where this wasn't a clear
win (the struct is too large, or is grouped in some other interesting
way).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255003 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-08 04:32:54 +00:00