Commit Graph

369 Commits

Author SHA1 Message Date
Peter Collingbourne
b981e1c7e5 Introduce GlobalSplit pass.
This pass splits globals into elements using inrange annotations on
getelementptr indices.

Differential Revision: https://reviews.llvm.org/D22295

llvm-svn: 287178
2016-11-16 23:40:26 +00:00
Tom Stellard
b2bb468ce3 RegAllocGreedy: Properly initialize this pass, so that -run-pass will work
Reviewers: qcolombet, MatzeB

Subscribers: wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D26572

llvm-svn: 286895
2016-11-14 21:50:13 +00:00
Igor Laevsky
1777237add [LCSSA] Perform LCSSA verification only for the current loop nest.
Now LPPassManager will run LCSSA verification only for the top-level loop
which was processed on the current iteration.

Differential Revision: https://reviews.llvm.org/D25873

llvm-svn: 285394
2016-10-28 12:57:20 +00:00
Dehao Chen
ecb41605f5 Add Loop Sink pass to reverse the LICM based of basic block frequency.
Summary: LICM may hoist instructions to preheader speculatively. Before code generation, we need to sink down the hoisted instructions inside to loop if it's beneficial. This pass is a reverse of LICM: looking at instructions in preheader and sinks the instruction to basic blocks inside the loop body if basic block frequency is smaller than the preheader frequency.

Reviewers: hfinkel, davidxl, chandlerc

Subscribers: anna, modocache, mgorny, beanz, reames, dberlin, chandlerc, mcrosier, junbuml, sanjoy, mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D22778

llvm-svn: 285308
2016-10-27 16:30:08 +00:00
Michael Ilseman
eba5480140 Add -strip-nonlinetable-debuginfo capability
This adds a new function to DebugInfo.cpp that takes an llvm::Module
as input and removes all debug info metadata that is not directly
needed for line tables, thus effectively stripping all type and
variable information from the module.

The primary motivation for this feature was the bitcode work flow
(cf. http://lists.llvm.org/pipermail/llvm-dev/2016-June/100643.html
for more background). This is not wired up yet, but will be in
subsequent patches.  For testing, the new functionality is exposed to
opt with a -strip-nonlinetable-debuginfo option.

The secondary use-case (and one that works right now!) is as a
reduction pass in bugpoint. I added two new bugpoint options
(-disable-strip-debuginfo and -disable-strip-debug-types) to control
the new features. By default it will first attempt to remove all debug
information, then only the type info, and then proceed to hack at any
remaining MDNodes.

Thanks to Adrian Prantl for stewarding this patch!

llvm-svn: 285094
2016-10-25 18:44:13 +00:00
Anna Thomas
0e0d440281 [StripGCRelocates] New pass to remove gc.relocates added by RS4GC
Summary:
Utility pass to remove gc.relocates created by rewrite statepoints for GC.
With respect to safepoint verification, the IR generated would be incorrect, and cannot run
as such.

This would be a single transformation on the final optimized IR.
The benefit of the pass is for easy analysis when the IRs are 'polluted' by too
many gc.relocates.
Added tests.

test run: All RS4GC tests with -verify option. Local downstream tests on large
IR files. This also works when the pointer being gc.relocated is another
gc.relocate.

Reviewers: sanjoy, reames

Subscribers: beanz, mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D25096

llvm-svn: 284855
2016-10-21 18:43:16 +00:00
Rong Xu
40080ca01c Conditionally eliminate library calls where the result value is not used
Summary:
This pass shrink-wraps a condition to some library calls where the call
result is not used. For example:
   sqrt(val);
 is transformed to
   if (val < 0)
     sqrt(val);
Even if the result of library call is not being used, the compiler cannot
safely delete the call because the function can set errno on error
conditions.
Note in many functions, the error condition solely depends on the incoming
parameter. In this optimization, we can generate the condition can lead to
the errno to shrink-wrap the call. Since the chances of hitting the error
condition is low, the runtime call is effectively eliminated.

These partially dead calls are usually results of C++ abstraction penalty
exposed by inlining. This optimization hits 108 times in 19 C/C++ programs
in SPEC2006.

Reviewers: hfinkel, mehdi_amini, davidxl

Subscribers: modocache, mgorny, mehdi_amini, xur, llvm-commits, beanz

Differential Revision: https://reviews.llvm.org/D24414

llvm-svn: 284542
2016-10-18 21:36:27 +00:00
Tim Northover
dc91ae935f GlobalISel: rename legalizer components to match others.
The previous names were both misleading (the MachineLegalizer actually
contained the info tables) and inconsistent with the selector & translator (in
having a "Machine") prefix. This should make everything sensible again.

The only functional change is the name of a couple of command-line options.

llvm-svn: 284287
2016-10-14 22:18:18 +00:00
Michael Ilseman
65a382e8fc Revert "Add -strip-nonlinetable-debuginfo capability"
This reverts commit r283473.

Reverted until review is completed.

llvm-svn: 283478
2016-10-06 18:30:26 +00:00
Michael Ilseman
ae58e6368d Add -strip-nonlinetable-debuginfo capability
This adds a new function to DebugInfo.cpp that takes an llvm::Module
as input and removes all debug info metadata that is not directly
needed for line tables, thus effectively stripping all type and
variable information from the module.

The primary motivation for this feature was the bitcode work flow
(cf. http://lists.llvm.org/pipermail/llvm-dev/2016-June/100643.html
for more background). This is not wired up yet, but will be in
subsequent patches.  For testing, the new functionality is exposed to
opt with a -strip-nonlinetable-debuginfo option.

The secondary use-case (and one that works right now!) is as a
reduction pass in bugpoint. I added two new bugpoint options
(-disable-strip-debuginfo and -disable-strip-debug-types) to control
the new features. By default it will first attempt to remove all debug
information, then only the type info, and then proceed to hack at any
remaining MDNodes.

llvm-svn: 283473
2016-10-06 17:58:38 +00:00
Matt Arsenault
cfe01e963c Move AArch64BranchRelaxation to generic code
llvm-svn: 283459
2016-10-06 15:38:53 +00:00
Mehdi Amini
21a9844262 Rename NameAnonFunctions to NameAnonGlobals to match what it is doing (NFC)
llvm-svn: 281745
2016-09-16 16:56:30 +00:00
Sriraman Tallam
0bea49c555 [PM] Port CFGViewer and CFGPrinter to the new Pass Manager
Differential Revision: https://reviews.llvm.org/D24592

llvm-svn: 281640
2016-09-15 18:35:27 +00:00
Hal Finkel
d3039d9a41 Add a counter-function insertion pass
As discussed in https://reviews.llvm.org/D22666, our current mechanism to
support -pg profiling, where we insert calls to mcount(), or some similar
function, is fundamentally broken. We insert these calls in the frontend, which
means they get duplicated when inlining, and so the accumulated execution
counts for the inlined-into functions are wrong.

Because we don't want the presence of these functions to affect optimizaton,
they should be inserted in the backend. Here's a pass which would do just that.
The knowledge of the name of the counting function lives in the frontend, so
we're passing it here as a function attribute. Clang will be updated to use
this mechanism.

Differential Revision: https://reviews.llvm.org/D22825

llvm-svn: 280347
2016-09-01 09:42:39 +00:00
Geoff Berry
4a45626e2f [EarlyCSE] Optionally use MemorySSA. NFC.
Summary:
Use MemorySSA, if requested, to do less conservative memory dependency
checking.

This change doesn't enable the MemorySSA enhanced EarlyCSE in the
default pipelines, so should be NFC.

Reviewers: dberlin, sanjoy, reames, majnemer

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D19821

llvm-svn: 280279
2016-08-31 19:24:10 +00:00
Quentin Colombet
1636e7c63b [GlobalISel] Add a fallback path to SDISel.
When global-isel fails on a MachineFunction MF, MF will be cleaned up
and given to SDISel.
Thanks to this fallback, we can already perform correctness test even if
we support only a small portion of the functions in a test.

llvm-svn: 279891
2016-08-27 00:18:31 +00:00
Chandler Carruth
90665f11d7 [PM] Port the always inliner to the new pass manager in a much more
minimal and boring form than the old pass manager's version.

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

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

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

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

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

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

Anyways, hopefully a reasonable starting point for this pass.

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

llvm-svn: 278896
2016-08-17 02:56:20 +00:00
Teresa Johnson
8d0046afe0 [PM] Port LoopDataPrefetch to new pass manager
Summary:
Refactor the existing support into a LoopDataPrefetch implementation
class and a LoopDataPrefetchLegacyPass class that invokes it.
Add a new LoopDataPrefetchPass for the new pass manager that utilizes
the LoopDataPrefetch implementation class.

Reviewers: mehdi_amini

Subscribers: sanjoy, mzolotukhin, nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D23483

llvm-svn: 278591
2016-08-13 04:11:27 +00:00
Michael Kuperstein
ff7325ed4c [PM] Port LowerInvoke to the new pass manager
llvm-svn: 278531
2016-08-12 17:28:27 +00:00
Teresa Johnson
69629c2314 [PM] Port NameAnonFunction pass to new pass manager
Summary:
Port the NameAnonFunction pass and add a test.

Depends on D23439.

Reviewers: mehdi_amini

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D23440

llvm-svn: 278509
2016-08-12 14:03:36 +00:00
Michael Kuperstein
3948eae2ef [PM] Port SpeculativeExecution to the new PM
Differential Revision: https://reviews.llvm.org/D23033

llvm-svn: 277393
2016-08-01 21:48:33 +00:00
Brendon Cahoon
e37295579e MachinePipeliner pass that implements Swing Modulo Scheduling
Software pipelining is an optimization for improving ILP by
overlapping loop iterations. Swing Modulo Scheduling (SMS) is
an implementation of software pipelining that attempts to
reduce register pressure and generate efficient pipelines with
a low compile-time cost.

This implementaion of SMS is a target-independent back-end pass.
When enabled, the pass should run just prior to the register
allocation pass, while the machine IR is in SSA form. If the pass
is successful, then the original loop is replaced by the optimized
loop. The optimized loop contains one or more prolog blocks, the
pipelined kernel, and one or more epilog blocks.

This pass is enabled for Hexagon only. To enable for other targets,
a couple of target specific hooks must be implemented, and the
pass needs to be called from the target's TargetMachine
implementation.

Differential Review: http://reviews.llvm.org/D16829

llvm-svn: 277169
2016-07-29 16:44:44 +00:00
Adam Nemet
9449a00cc1 [BPI] Add new LazyBPI analysis
Summary:
The motivation is the same as in D22141: In order to add the hotness
attribute to optimization remarks we need BFI to be available in all
passes that emit optimization remarks.  BFI depends on BPI so unless we
make this lazy as well we would still compute BPI unconditionally.

The solution is to use the new LazyBPI pass in LazyBFI and only compute
BPI when computation of BFI is requested by the client.

I extended the laziness test using a LoopDistribute test to also cover
BPI.

Reviewers: hfinkel, davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D22835

llvm-svn: 277083
2016-07-28 23:31:12 +00:00
Michael Kuperstein
9f5bccd412 [PM] Port LowerGuardIntrinsic to the new PM.
llvm-svn: 277057
2016-07-28 22:08:41 +00:00
David Majnemer
618a29cbe1 [coroutines] Part 3 of N: Adding Boilerplate for Coroutine Passes
This adds boilerplate code for all coroutine passes,
the passes are no-ops for now.
Also, a small test has been added to verify that passes execute in
the expected order or not at all if coroutine support is disabled.

Patch by Gor Nishanov!

Differential Revision: https://reviews.llvm.org/D22847

llvm-svn: 277033
2016-07-28 21:04:31 +00:00
Ahmed Bougacha
fdc59ed6fb [GlobalISel] Introduce an instruction selector.
And implement it for AArch64, supporting x/w ADD/OR.

Differential Revision: https://reviews.llvm.org/D22373

llvm-svn: 276875
2016-07-27 14:31:55 +00:00
Michael Kuperstein
e46ec47350 [PM] Port SymbolRewriter to the new PM
Differential Revision: https://reviews.llvm.org/D22703

llvm-svn: 276687
2016-07-25 20:52:00 +00:00
Tim Northover
e35b03e144 GlobalISel: implement legalization pass, with just one transformation.
This adds the actual MachineLegalizeHelper to do the work and a trivial pass
wrapper that legalizes all instructions in a MachineFunction. Currently the
only transformation supported is splitting up a vector G_ADD into one acting on
smaller vectors.

llvm-svn: 276461
2016-07-22 20:03:43 +00:00
Wei Mi
6b0c2bfc2b [PM] Port NaryReassociate to the new PM
Differential Revision: https://reviews.llvm.org/D22648

llvm-svn: 276349
2016-07-21 22:28:52 +00:00
Teresa Johnson
ef461cc7ce [PM] Port FunctionImport Pass to new PM
Summary: Port FunctionImport Pass to new PM.

Reviewers: mehdi_amini, davide

Subscribers: davidxl, llvm-commits

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

llvm-svn: 275916
2016-07-18 21:22:24 +00:00
Adam Nemet
40da722c35 [LoopDist] Port to new PM
Summary:
The direct motivation for the port is to ensure that the OptRemarkEmitter
tests work with the new PM.

This remains a function pass because we not only create multiple loops
but could also version the original loop.

In the test I need to invoke opt
with -passes='require<aa>,loop-distribute'.  LoopDistribute does not
directly depend on AA however LAA does.  LAA uses getCachedResult so
I *think* we need manually pull in 'aa'.

Reviewers: davidxl, silvas

Subscribers: sanjoy, llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D22437

llvm-svn: 275811
2016-07-18 16:29:27 +00:00
Adam Nemet
3e5f3565d1 [OptRemarkEmitter] Port to new PM
Summary:
The main goal is to able to start using the new OptRemarkEmitter
analysis from the LoopVectorizer.  Since the vectorizer was recently
converted to the new PM, it makes sense to convert this analysis as
well.

This pass is currently tested through the LoopDistribution pass, so I am
also porting LoopDistribution to get coverage for this analysis with the
new PM.

Reviewers: davidxl, silvas

Subscribers: llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D22436

llvm-svn: 275810
2016-07-18 16:29:21 +00:00
Dehao Chen
84b1505453 [PM] Convert IVUsers analysis to new pass manager.
Summary: Convert IVUsers analysis to new pass manager.

Reviewers: davidxl, silvas

Subscribers: junbuml, sanjoy, llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D22434

llvm-svn: 275698
2016-07-16 22:51:33 +00:00
Adam Nemet
cb89dd6834 [OptRemark,LDist] RFC: Add hotness attribute
Summary:
This is the first set of changes implementing the RFC from
http://thread.gmane.org/gmane.comp.compilers.llvm.devel/98334

This is a cross-sectional patch; rather than implementing the hotness
attribute for all optimization remarks and all passes in a patch set, it
implements it for the 'missed-optimization' remark for Loop
Distribution.  My goal is to shake out the design issues before scaling
it up to other types and passes.

Hotness is computed as an integer as the multiplication of the block
frequency with the function entry count.  It's only printed in opt
currently since clang prints the diagnostic fields directly.  E.g.:

  remark: /tmp/t.c:3:3: loop not distributed: use -Rpass-analysis=loop-distribute for more info (hotness: 300)

A new API added is similar to emitOptimizationRemarkMissed.  The
difference is that it additionally takes a code region that the
diagnostic corresponds to.  From this, hotness is computed using BFI.
The new API is exposed via an analysis pass so that it can be made
dependent on LazyBFI.  (Thanks to Hal for the analysis pass idea.)

This feature can all be enabled by setDiagnosticHotnessRequested in the
LLVM context.  If this is off, LazyBFI is not calculated (D22141) so
there should be no overhead.

A new command-line option is added to turn this on in opt.

My plan is to switch all user of emitOptimizationRemark* to use this
module instead.

Reviewers: hfinkel

Subscribers: rcox2, mzolotukhin, llvm-commits

Differential Revision: http://reviews.llvm.org/D21771

llvm-svn: 275583
2016-07-15 17:23:20 +00:00
Dehao Chen
7ad979406b [PM] Convert LoopInstSimplify Pass to new PM
Summary: Convert LoopInstSimplify to new PM. Unfortunately there is no exisiting unittest for this pass.

Reviewers: davidxl, silvas

Subscribers: silvas, llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D22280

llvm-svn: 275576
2016-07-15 16:42:11 +00:00
Sebastian Pop
b636a525d4 code hoisting pass based on GVN
This pass hoists duplicated computations in the program. The primary goal of
gvn-hoist is to reduce the size of functions before inline heuristics to reduce
the total cost of function inlining.

Pass written by Sebastian Pop, Aditya Kumar, Xiaoyu Hu, and Brian Rzycki.
Important algorithmic contributions by Daniel Berlin under the form of reviews.

Differential Revision: http://reviews.llvm.org/D19338

llvm-svn: 275561
2016-07-15 13:45:20 +00:00
Jun Bum Lim
11a2b91ee2 [PM] Port Dead Loop Deletion Pass to the new PM
Summary: Port Dead Loop Deletion Pass to the new pass manager.

Reviewers: silvas, davide

Subscribers: llvm-commits, sanjoy, mcrosier

Differential Revision: https://reviews.llvm.org/D21483

llvm-svn: 275453
2016-07-14 18:28:29 +00:00
Nico Weber
e9dcd55ff0 Revert r275401, it caused PR28551.
llvm-svn: 275420
2016-07-14 14:41:25 +00:00
Sebastian Pop
f51ad9a239 code hoisting pass based on GVN
This pass hoists duplicated computations in the program. The primary goal of
gvn-hoist is to reduce the size of functions before inline heuristics to reduce
the total cost of function inlining.

Pass written by Sebastian Pop, Aditya Kumar, Xiaoyu Hu, and Brian Rzycki.
Important algorithmic contributions by Daniel Berlin under the form of reviews.

Differential Revision: http://reviews.llvm.org/D19338

llvm-svn: 275401
2016-07-14 12:18:53 +00:00
Dean Michael Berris
b3cb9bd89d XRay: Add entry and exit sleds
Summary:
In this patch we implement the following parts of XRay:

- Supporting a function attribute named 'function-instrument' which currently only supports 'xray-always'. We should be able to use this attribute for other instrumentation approaches.
- Supporting a function attribute named 'xray-instruction-threshold' used to determine whether a function is instrumented with a minimum number of instructions (IR instruction counts).
- X86-specific nop sleds as described in the white paper.
- A machine function pass that adds the different instrumentation marker instructions at a very late stage.
- A way of identifying which return opcode is considered "normal" for each architecture.

There are some caveats here:

1) We don't handle PATCHABLE_RET in platforms other than x86_64 yet -- this means if IR used PATCHABLE_RET directly instead of a normal ret, instruction lowering for that platform might do the wrong thing. We think this should be handled at instruction selection time to by default be unpacked for platforms where XRay is not availble yet.

2) The generated section for X86 is different from what is described from the white paper for the sole reason that LLVM allows us to do this neatly. We're taking the opportunity to deviate from the white paper from this perspective to allow us to get richer information from the runtime library.

Reviewers: sanjoy, eugenis, kcc, pcc, echristo, rnk

Subscribers: niravd, majnemer, atrick, rnk, emaste, bmakam, mcrosier, mehdi_amini, llvm-commits

Differential Revision: http://reviews.llvm.org/D19904

llvm-svn: 275367
2016-07-14 04:06:33 +00:00
Adam Nemet
071e00e973 [BFI] Add new LazyBFI analysis pass
Summary:
This is necessary for D21771.  In order to add the hotness attribute to
optimization remarks we need BFI to be available in all passes that emit
optimization remarks.

However we don't want to pay for computing BFI unless the hotness
attribute is requested.

This is achieved by making BFI lazy at the very high-level through a new
analysis pass -- BFI is not calculated unless requested.

I am adding a test to check the laziness under D21771 where the first
user of the analysis is added.

Reviewers: hfinkel, dexonsmith, davidxl

Subscribers: davidxl, dexonsmith, llvm-commits

Differential Revision: http://reviews.llvm.org/D22141

llvm-svn: 275250
2016-07-13 05:01:48 +00:00
Dehao Chen
9b4dc6d522 New pass manager for LICM.
Summary: Port LICM to the new pass manager.

Reviewers: davidxl, silvas

Subscribers: krasin, vitalybuka, silvas, davide, sanjoy, llvm-commits, mehdi_amini

Differential Revision: http://reviews.llvm.org/D21772

llvm-svn: 275222
2016-07-12 22:37:48 +00:00
Dehao Chen
c181c867aa [PM] Port LoopIdiomRecognize Pass to new PM
Summary: Port LoopIdiomRecognize Pass to new PM

Reviewers: davidxl

Subscribers: davide, sanjoy, mzolotukhin, llvm-commits

Differential Revision: http://reviews.llvm.org/D22250

llvm-svn: 275202
2016-07-12 18:45:51 +00:00
Vitaly Buka
d3a08f0254 Revert "New pass manager for LICM."
Summary: This reverts commit r275118.

Subscribers: sanjoy, mehdi_amini

Differential Revision: http://reviews.llvm.org/D22259

llvm-svn: 275156
2016-07-12 06:25:32 +00:00
Dehao Chen
75ac849ab9 New pass manager for LICM.
Summary: Port LICM to the new pass manager.

Reviewers: davidxl, silvas

Subscribers: silvas, davide, sanjoy, llvm-commits, mehdi_amini

Differential Revision: http://reviews.llvm.org/D21772

llvm-svn: 275118
2016-07-11 22:45:24 +00:00
Xinliang David Li
fa55840e59 Rename LoopAccessAnalysis to LoopAccessLegacyAnalysis /NFC
llvm-svn: 274927
2016-07-08 20:55:26 +00:00
Wei Mi
3d33c761b3 [PM] Port UnreachableBlockElim to the new Pass Manager
Differential Revision: http://reviews.llvm.org/D22124

llvm-svn: 274824
2016-07-08 03:32:49 +00:00
Chad Rosier
470696c7ac [MemorySSA] Reinstate the legacy printer and verifier.
Differential Revision: http://reviews.llvm.org/D22058

llvm-svn: 274679
2016-07-06 21:20:47 +00:00
George Burgess IV
9f9488ba33 [CFLAA] Split into Anders+Steens analysis.
StratifiedSets (as implemented) is very fast, but its accuracy is also
limited. If we take a more aggressive andersens-like approach, we can be
way more accurate, but we'll also end up being slower.

So, we've decided to split CFLAA into CFLSteensAA and CFLAndersAA.

Long-term, we want to end up in a place where CFLSteens is queried
first; if it can provide an answer, great (since queries are basically
map lookups). Otherwise, we'll fall back to CFLAnders, BasicAA, etc.

This patch splits everything out so we can try to do something like
that when we get a reasonable CFLAnders implementation.

Patch by Jia Chen.

Differential Revision: http://reviews.llvm.org/D21910

llvm-svn: 274589
2016-07-06 00:26:41 +00:00
Michael Kuperstein
42c218049d [PM] Port ConstantHoisting to the new Pass Manager
Differential Revision: http://reviews.llvm.org/D21945

llvm-svn: 274411
2016-07-02 00:16:47 +00:00