Commit Graph

195 Commits

Author SHA1 Message Date
Philip Pfaffe 685c76d7a3 [NewPM][TSan] Reiterate the TSan port
Summary:
Second iteration of D56433 which got reverted in rL350719. The problem
in the previous version was that we dropped the thunk calling the tsan init
function. The new version keeps the thunk which should appease dyld, but is not
actually OK wrt. the current semantics of function passes. Hence, add a
helper to insert the functions only on the first time. The helper
allows hooking into the insertion to be able to append them to the
global ctors list.

Reviewers: chandlerc, vitalybuka, fedor.sergeev, leonardchan

Subscribers: hiraditya, bollu, llvm-commits

Differential Revision: https://reviews.llvm.org/D56538

llvm-svn: 351314
2019-01-16 09:28:01 +00:00
Fedor Sergeev b7871405fa [LoopUnroll] add parsing for unroll parameters in -passes pipeline
Allow to specify loop-unrolling with optional parameters explicitly
spelled out in -passes pipeline specification.
Introducing somewhat generic way of specifying parameters parsing via
FUNCTION_PASS_PARAMETRIZED pass registration.

Syntax of parametrized unroll pass name is as follows:
   'unroll<' parameter-list '>'

Where parameter-list is ';'-separate list of parameter names and optlevel
   optlevel: 'O[0-3]'
   parameter: { 'partial' | 'peeling' | 'runtime' | 'upperbound' }
   negated:  'no-' parameter

Example:
   -passes=loop(unroll<O3;runtime;no-upperbound>)

    this invokes LoopUnrollPass configured with OptLevel=3,
    Runtime, no UpperBound, everything else by default.

llvm-svn: 350808
2019-01-10 10:01:53 +00:00
Florian Hahn 9697d2a764 Revert r350647: "[NewPM] Port tsan"
This patch breaks thread sanitizer on some macOS builders, e.g.
http://green.lab.llvm.org/green/job/clang-stage1-configure-RA/52725/

llvm-svn: 350719
2019-01-09 13:32:16 +00:00
Philip Pfaffe 82f995db75 [NewPM] Port tsan
A straightforward port of tsan to the new PM, following the same path
as D55647.

Differential Revision: https://reviews.llvm.org/D56433

llvm-svn: 350647
2019-01-08 19:21:57 +00:00
Philip Pfaffe efb5ad1c58 [DA][NewPM] Add a printerpass and port the testsuite
The new-pm version of DA is untested. Testing requires a printer, so
add that and use it in the existing DA tests.

Differential Revision: https://reviews.llvm.org/D56386

llvm-svn: 350624
2019-01-08 14:06:58 +00:00
Teresa Johnson 853b962416 [ThinLTO] Handle chains of aliases
At -O0, globalopt is not run during the compile step, and we can have a
chain of an alias having an immediate aliasee of another alias. The
summaries are constructed assuming aliases in a canonical form
(flattened chains), and as a result only the base object but no
intermediate aliases were preserved.

Fix by adding a pass that canonicalize aliases, which ensures each
alias is a direct alias of the base object.

Reviewers: pcc, davidxl

Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, arphaman, llvm-commits

Differential Revision: https://reviews.llvm.org/D54507

llvm-svn: 350423
2019-01-04 19:04:54 +00:00
Philip Pfaffe b39a97c8f6 [NewPM] Port Msan
Summary:
Keeping msan a function pass requires replacing the module level initialization:
That means, don't define a ctor function which calls __msan_init, instead just
declare the init function at the first access, and add that to the global ctors
list.

Changes:
- Pull the actual sanitizer and the wrapper pass apart.
- Add a newpm msan pass. The function pass inserts calls to runtime
  library functions, for which it inserts declarations as necessary.
- Update tests.

Caveats:
- There is one test that I dropped, because it specifically tested the
  definition of the ctor.

Reviewers: chandlerc, fedor.sergeev, leonardchan, vitalybuka

Subscribers: sdardis, nemanjai, javed.absar, hiraditya, kbarton, bollu, atanasyan, jsji

Differential Revision: https://reviews.llvm.org/D55647

llvm-svn: 350305
2019-01-03 13:42:44 +00:00
Michael Kruse 7244852557 [Unroll/UnrollAndJam/Vectorizer/Distribute] Add followup loop attributes.
When multiple loop transformation are defined in a loop's metadata, their order of execution is defined by the order of their respective passes in the pass pipeline. For instance, e.g.

    #pragma clang loop unroll_and_jam(enable)
    #pragma clang loop distribute(enable)

is the same as

    #pragma clang loop distribute(enable)
    #pragma clang loop unroll_and_jam(enable)

and will try to loop-distribute before Unroll-And-Jam because the LoopDistribute pass is scheduled after UnrollAndJam pass. UnrollAndJamPass only supports one inner loop, i.e. it will necessarily fail after loop distribution. It is not possible to specify another execution order. Also,t the order of passes in the pipeline is subject to change between versions of LLVM, optimization options and which pass manager is used.

This patch adds 'followup' attributes to various loop transformation passes. These attributes define which attributes the resulting loop of a transformation should have. For instance,

     = !{!0, , !2}
     = !{!"llvm.loop.unroll_and_jam.enable"}
     = !{!"llvm.loop.unroll_and_jam.followup_inner", !3}
     = !{!"llvm.loop.distribute.enable"}

defines a loop ID () to be unrolled-and-jammed () and then the attribute  to be added to the jammed inner loop, which contains the instruction to distribute the inner loop.

Currently, in both pass managers, pass execution is in a fixed order and UnrollAndJamPass will not execute again after LoopDistribute. We hope to fix this in the future by allowing pass managers to run passes until a fixpoint is reached, use Polly to perform these transformations, or add a loop transformation pass which takes the order issue into account.

For mandatory/forced transformations (e.g. by having been declared by #pragma omp simd), the user must be notified when a transformation could not be performed. It is not possible that the responsible pass emits such a warning because the transformation might be 'hidden' in a followup attribute when it is executed, or it is not present in the pipeline at all. For this reason, this patche introduces a WarnMissedTransformations pass, to warn about orphaned transformations.

Since this changes the user-visible diagnostic message when a transformation is applied, two test cases in the clang repository need to be updated.

To ensure that no other transformation is executed before the intended one, the attribute `llvm.loop.disable_nonforced` can be added which should disable transformation heuristics before the intended transformation is applied. E.g. it would be surprising if a loop is distributed before a #pragma unroll_and_jam is applied.

With more supported code transformations (loop fusion, interchange, stripmining, offloading, etc.), transformations can be used as building blocks for more complex transformations (e.g. stripmining+stripmining+interchange -> tiling).

Reviewed By: hfinkel, dmgreen

Differential Revision: https://reviews.llvm.org/D49281
Differential Revision: https://reviews.llvm.org/D55288

llvm-svn: 348944
2018-12-12 17:32:52 +00:00
Max Kazantsev b9e65cbddf Introduce llvm.experimental.widenable_condition intrinsic
This patch introduces a new instinsic `@llvm.experimental.widenable_condition`
that allows explicit representation for guards. It is an alternative to using
`@llvm.experimental.guard` intrinsic that does not contain implicit control flow.

We keep finding places where `@llvm.experimental.guard` is not supported or
treated too conservatively, and there are 2 reasons to that:

- `@llvm.experimental.guard` has memory write side effect to model implicit control flow,
  and this sometimes confuses passes and analyzes that work with memory;
- Not all passes and analysis are aware of the semantics of guards. These passes treat them
  as regular throwing call and have no idea that the condition of guard may be used to prove
  something. One well-known place which had caused us troubles in the past is explicit loop
  iteration count calculation in SCEV. Another example is new loop unswitching which is not
  aware of guards. Whenever a new pass appears, we potentially have this problem there.

Rather than go and fix all these places (and commit to keep track of them and add support
in future), it seems more reasonable to leverage the existing optimizer's logic as much as possible.
The only significant difference between guards and regular explicit branches is that guard's condition
can be widened. It means that a guard contains (explicitly or implicitly) a `deopt` block successor,
and it is always legal to go there no matter what the guard condition is. The other successor is
a guarded block, and it is only legal to go there if the condition is true.

This patch introduces a new explicit form of guards alternative to `@llvm.experimental.guard`
intrinsic. Now a widenable guard can be represented in the CFG explicitly like this:


    %widenable_condition = call i1 @llvm.experimental.widenable.condition()
    %new_condition = and i1 %cond, %widenable_condition
    br i1 %new_condition, label %guarded, label %deopt

  guarded:
    ; Guarded instructions

  deopt:
    call type @llvm.experimental.deoptimize(<args...>) [ "deopt"(<deopt_args...>) ]

The new intrinsic `@llvm.experimental.widenable.condition` has semantics of an
`undef`, but the intrinsic prevents the optimizer from folding it early. This form
should exploit all optimization boons provided to `br` instuction, and it still can be
widened by replacing the result of `@llvm.experimental.widenable.condition()`
with `and` with any arbitrary boolean value (as long as the branch that is taken when
it is `false` has a deopt and has no side-effects).

For more motivation, please check llvm-dev discussion "[llvm-dev] Giving up using
implicit control flow in guards".

This patch introduces this new intrinsic with respective LangRef changes and a pass
that converts old-style guards (expressed as intrinsics) into the new form.

The naming discussion is still ungoing. Merging this to unblock further items. We can
later change the name of this intrinsic.

Reviewed By: reames, fedor.sergeev, sanjoy
Differential Revision: https://reviews.llvm.org/D51207

llvm-svn: 348593
2018-12-07 14:39:46 +00:00
Markus Lavin 4dc4ebd606 [PM] Port LoadStoreVectorizer to the new pass manager.
Differential Revision: https://reviews.llvm.org/D54848

llvm-svn: 348570
2018-12-07 08:23:37 +00:00
Vitaly Buka b8e6fa6638 [stack-safety] Empty local passes for Stack Safety Global Analysis
Reviewers: eugenis, vlad.tsyrklevich

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D54541

llvm-svn: 347610
2018-11-26 23:05:48 +00:00
Vitaly Buka 4493fe1c1b [stack-safety] Empty local passes for Stack Safety Local Analysis
Reviewers: eugenis, vlad.tsyrklevich

Subscribers: mgorny, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D54502

llvm-svn: 347602
2018-11-26 21:57:47 +00:00
Mikael Holmen b6f76002d9 [PM] Port Scalarizer to the new pass manager.
Patch by: markus (Markus Lavin)

Reviewers: chandlerc, fedor.sergeev

Reviewed By: fedor.sergeev

Subscribers: llvm-commits, Ka-Ka, bjope

Differential Revision: https://reviews.llvm.org/D54695

llvm-svn: 347392
2018-11-21 14:00:17 +00:00
Fedor Sergeev 412ed34744 [LoopUnroll] allow customization for new-pass-manager version of LoopUnroll
Unlike its legacy counterpart new pass manager's LoopUnrollPass does
not provide any means to select which flavors of unroll to run
(runtime, peeling, partial), relying on global defaults.

In some cases having ability to run a restricted LoopUnroll that
does more than LoopFullUnroll is needed.

Introduced LoopUnrollOptions to select optional unroll behaviors.
Added 'unroll<peeling>' to PassRegistry mainly for the sake of testing.

Reviewers: chandlerc, tejohnson
Differential Revision: https://reviews.llvm.org/D53440

llvm-svn: 345723
2018-10-31 14:33:14 +00:00
Leonard Chan eebecb3214 Revert "[PassManager/Sanitizer] Enable usage of ported AddressSanitizer passes with -fsanitize=address"
This reverts commit 8d6af840396f2da2e4ed6aab669214ae25443204 and commit
b78d19c287b6e4a9abc9fb0545de9a3106d38d3d which causes slower build times
by initializing the AddressSanitizer on every function run.

The corresponding revisions are https://reviews.llvm.org/D52814 and
https://reviews.llvm.org/D52739.

llvm-svn: 345433
2018-10-26 22:51:51 +00:00
Leonard Chan 64e21b5cfd [PassManager/Sanitizer] Port of AddresSanitizer pass from legacy to new PassManager
This patch ports the legacy pass manager to the new one to take advantage of
the benefits of the new PM. This involved moving a lot of the declarations for
`AddressSantizer` to a header so that it can be publicly used via
PassRegistry.def which I believe contains all the passes managed by the new PM.

This patch essentially decouples the instrumentation from the legacy PM such
hat it can be used by both legacy and new PM infrastructure.

Differential Revision: https://reviews.llvm.org/D52739

llvm-svn: 344274
2018-10-11 18:31:51 +00:00
Aditya Kumar 9e20ade72a Add support for new pass manager
Modified the testcases to use both pass managers
Use single commandline flag for both pass managers.

Differential Revision: https://reviews.llvm.org/D52708
Reviewers: sebpop, tejohnson, brzycki, SirishP
Reviewed By: tejohnson, brzycki

llvm-svn: 343662
2018-10-03 05:55:20 +00:00
Fedor Sergeev ee8d31c49e [New PM] Introducing PassInstrumentation framework
Pass Execution Instrumentation interface enables customizable instrumentation
of pass execution, as per "RFC: Pass Execution Instrumentation interface"
posted 06/07/2018 on llvm-dev@

The intent is to provide a common machinery to implement all
the pass-execution-debugging features like print-before/after,
opt-bisect, time-passes etc.

Here we get a basic implementation consisting of:
* PassInstrumentationCallbacks class that handles registration of callbacks
  and access to them.

* PassInstrumentation class that handles instrumentation-point interfaces
  that call into PassInstrumentationCallbacks.

* Callbacks accept StringRef which is just a name of the Pass right now.
  There were some ideas to pass an opaque wrapper for the pointer to pass instance,
  however it appears that pointer does not actually identify the instance
  (adaptors and managers might have the same address with the pass they govern).
  Hence it was decided to go simple for now and then later decide on what the proper
  mental model of identifying a "pass in a phase of pipeline" is.

* Callbacks accept llvm::Any serving as a wrapper for const IRUnit*, to remove direct dependencies
  on different IRUnits (e.g. Analyses).

* PassInstrumentationAnalysis analysis is explicitly requested from PassManager through
  usual AnalysisManager::getResult. All pass managers were updated to run that
  to get PassInstrumentation object for instrumentation calls.

* Using tuples/index_sequence getAnalysisResult helper to extract generic AnalysisManager's extra
  args out of a generic PassManager's extra args. This is the only way I was able to explicitly
  run getResult for PassInstrumentationAnalysis out of a generic code like PassManager::run or
  RepeatedPass::run.
  TODO: Upon lengthy discussions we agreed to accept this as an initial implementation
  and then get rid of getAnalysisResult by improving RepeatedPass implementation.

* PassBuilder takes PassInstrumentationCallbacks object to pass it further into
  PassInstrumentationAnalysis. Callbacks registration should be performed directly
  through PassInstrumentationCallbacks.

* new-pm tests updated to account for PassInstrumentationAnalysis being run

* Added PassInstrumentation tests to PassBuilderCallbacks unit tests.
  Other unit tests updated with registration of the now-required PassInstrumentationAnalysis.

  Made getName helper to return std::string (instead of StringRef initially) to fix
  asan builtbot failures on CGSCC tests.

Reviewers: chandlerc, philip.pfaffe
Differential Revision: https://reviews.llvm.org/D47858

llvm-svn: 342664
2018-09-20 17:08:45 +00:00
Eric Christopher 019889374b Temporarily Revert "[New PM] Introducing PassInstrumentation framework"
as it was causing failures in the asan buildbot.

This reverts commit r342597.

llvm-svn: 342616
2018-09-20 05:16:29 +00:00
Fedor Sergeev a5f279ea89 [New PM] Introducing PassInstrumentation framework
Pass Execution Instrumentation interface enables customizable instrumentation
of pass execution, as per "RFC: Pass Execution Instrumentation interface"
posted 06/07/2018 on llvm-dev@

The intent is to provide a common machinery to implement all
the pass-execution-debugging features like print-before/after,
opt-bisect, time-passes etc.

Here we get a basic implementation consisting of:
* PassInstrumentationCallbacks class that handles registration of callbacks
  and access to them.

* PassInstrumentation class that handles instrumentation-point interfaces
  that call into PassInstrumentationCallbacks.

* Callbacks accept StringRef which is just a name of the Pass right now.
  There were some ideas to pass an opaque wrapper for the pointer to pass instance,
  however it appears that pointer does not actually identify the instance
  (adaptors and managers might have the same address with the pass they govern).
  Hence it was decided to go simple for now and then later decide on what the proper
  mental model of identifying a "pass in a phase of pipeline" is.

* Callbacks accept llvm::Any serving as a wrapper for const IRUnit*, to remove direct dependencies
  on different IRUnits (e.g. Analyses).

* PassInstrumentationAnalysis analysis is explicitly requested from PassManager through
  usual AnalysisManager::getResult. All pass managers were updated to run that
  to get PassInstrumentation object for instrumentation calls.

* Using tuples/index_sequence getAnalysisResult helper to extract generic AnalysisManager's extra
  args out of a generic PassManager's extra args. This is the only way I was able to explicitly
  run getResult for PassInstrumentationAnalysis out of a generic code like PassManager::run or
  RepeatedPass::run.
  TODO: Upon lengthy discussions we agreed to accept this as an initial implementation
  and then get rid of getAnalysisResult by improving RepeatedPass implementation.

* PassBuilder takes PassInstrumentationCallbacks object to pass it further into
  PassInstrumentationAnalysis. Callbacks registration should be performed directly
  through PassInstrumentationCallbacks.

* new-pm tests updated to account for PassInstrumentationAnalysis being run

* Added PassInstrumentation tests to PassBuilderCallbacks unit tests.
  Other unit tests updated with registration of the now-required PassInstrumentationAnalysis.

Reviewers: chandlerc, philip.pfaffe
Differential Revision: https://reviews.llvm.org/D47858

llvm-svn: 342597
2018-09-19 22:42:57 +00:00
Fedor Sergeev 25de3f83be Revert rL342544: [New PM] Introducing PassInstrumentation framework
A bunch of bots fail to compile unittests. Reverting.

llvm-svn: 342552
2018-09-19 14:54:48 +00:00
Fedor Sergeev 875c938fec [New PM] Introducing PassInstrumentation framework
Summary:
Pass Execution Instrumentation interface enables customizable instrumentation
of pass execution, as per "RFC: Pass Execution Instrumentation interface"
posted 06/07/2018 on llvm-dev@

The intent is to provide a common machinery to implement all
the pass-execution-debugging features like print-before/after,
opt-bisect, time-passes etc.

Here we get a basic implementation consisting of:
* PassInstrumentationCallbacks class that handles registration of callbacks
  and access to them.

* PassInstrumentation class that handles instrumentation-point interfaces
  that call into PassInstrumentationCallbacks.

* Callbacks accept StringRef which is just a name of the Pass right now.
  There were some ideas to pass an opaque wrapper for the pointer to pass instance,
  however it appears that pointer does not actually identify the instance
  (adaptors and managers might have the same address with the pass they govern).
  Hence it was decided to go simple for now and then later decide on what the proper
  mental model of identifying a "pass in a phase of pipeline" is.

* Callbacks accept llvm::Any serving as a wrapper for const IRUnit*, to remove direct dependencies
  on different IRUnits (e.g. Analyses).

* PassInstrumentationAnalysis analysis is explicitly requested from PassManager through
  usual AnalysisManager::getResult. All pass managers were updated to run that
  to get PassInstrumentation object for instrumentation calls.

* Using tuples/index_sequence getAnalysisResult helper to extract generic AnalysisManager's extra
  args out of a generic PassManager's extra args. This is the only way I was able to explicitly
  run getResult for PassInstrumentationAnalysis out of a generic code like PassManager::run or
  RepeatedPass::run.
  TODO: Upon lengthy discussions we agreed to accept this as an initial implementation
  and then get rid of getAnalysisResult by improving RepeatedPass implementation.

* PassBuilder takes PassInstrumentationCallbacks object to pass it further into
  PassInstrumentationAnalysis. Callbacks registration should be performed directly
  through PassInstrumentationCallbacks.

* new-pm tests updated to account for PassInstrumentationAnalysis being run

* Added PassInstrumentation tests to PassBuilderCallbacks unit tests.
  Other unit tests updated with registration of the now-required PassInstrumentationAnalysis.

Reviewers: chandlerc, philip.pfaffe
Differential Revision: https://reviews.llvm.org/D47858

llvm-svn: 342544
2018-09-19 12:25:52 +00:00
Hiroshi Yamauchi 9775a620b0 [PGO] Control Height Reduction
Summary:
Control height reduction merges conditional blocks of code and reduces the
number of conditional branches in the hot path based on profiles.

if (hot_cond1) { // Likely true.
  do_stg_hot1();
}
if (hot_cond2) { // Likely true.
  do_stg_hot2();
}

->

if (hot_cond1 && hot_cond2) { // Hot path.
  do_stg_hot1();
  do_stg_hot2();
} else { // Cold path.
  if (hot_cond1) {
    do_stg_hot1();
  }
  if (hot_cond2) {
    do_stg_hot2();
  }
}

This speeds up some internal benchmarks up to ~30%.

Reviewers: davidxl

Reviewed By: davidxl

Subscribers: xbolva00, dmgreen, mehdi_amini, llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D50591

llvm-svn: 341386
2018-09-04 17:19:13 +00:00
Teresa Johnson 28023dbed7 [ThinLTO] Enable ThinLTO WholeProgramDevirt and LowerTypeTests in new PM
Summary:
Enable these passes for CFI and WPD in ThinLTO and LTO with the new pass
manager. Add a couple of tests for both PMs based on the clang tests
tools/clang/test/CodeGen/thinlto-distributed-cfi*.ll, but just test
through llvm-lto2 and not with distributed ThinLTO.

Reviewers: pcc

Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D49429

llvm-svn: 337461
2018-07-19 14:51:32 +00:00
Michael J. Spencer 7bb2767fba Recommit r335794 "Add support for generating a call graph profile from Branch Frequency Info." with fix for removed functions.
llvm-svn: 337140
2018-07-16 00:28:24 +00:00
David Green 963401d2be [UnrollAndJam] New Unroll and Jam pass
This is a simple implementation of the unroll-and-jam classical loop
optimisation.

The basic idea is that we take an outer loop of the form:

  for i..
    ForeBlocks(i)
    for j..
      SubLoopBlocks(i, j)
    AftBlocks(i)

Instead of doing normal inner or outer unrolling, we unroll as follows:

  for i... i+=2
    ForeBlocks(i)
    ForeBlocks(i+1)
    for j..
      SubLoopBlocks(i, j)
      SubLoopBlocks(i+1, j)
    AftBlocks(i)
    AftBlocks(i+1)
  Remainder Loop

So we have unrolled the outer loop, then jammed the two inner loops into
one. This can lead to a simpler inner loop if memory accesses can be shared
between the now jammed loops.

To do this we have to prove that this is all safe, both for the memory
accesses (using dependence analysis) and that ForeBlocks(i+1) can move before
AftBlocks(i) and SubLoopBlocks(i, j).

Differential Revision: https://reviews.llvm.org/D41953

llvm-svn: 336062
2018-07-01 12:47:30 +00:00
Chandler Carruth 7c557f804d [instsimplify] Move the instsimplify pass to use more obvious file names
and diretory.

Also cleans up all the associated naming to be consistent and removes
the public access to the pass ID which was unused in LLVM.

Also runs clang-format over parts that changed, which generally cleans
up a bunch of formatting.

This is in preparation for doing some internal cleanups to the pass.

Differential Revision: https://reviews.llvm.org/D47352

llvm-svn: 336028
2018-06-29 23:36:03 +00:00
Sean Fertile cd0d7634f6 Revert "Extend CFGPrinter and CallPrinter with Heat Colors"
This reverts r335996 which broke graph printing in Polly.

llvm-svn: 336000
2018-06-29 17:48:58 +00:00
Sean Fertile 3b0535b424 Extend CFGPrinter and CallPrinter with Heat Colors
Extends the CFGPrinter and CallPrinter with heat colors based on heuristics or
profiling information. The colors are enabled by default and can be toggled
on/off for CFGPrinter by using the option -cfg-heat-colors for both
-dot-cfg[-only] and -view-cfg[-only].  Similarly, the colors can be toggled
on/off for CallPrinter by using the option -callgraph-heat-colors for both
-dot-callgraph and -view-callgraph.

Patch by Rodrigo Caetano Rocha!

Differential Revision: https://reviews.llvm.org/D40425

llvm-svn: 335996
2018-06-29 17:13:58 +00:00
John Brawn bdbbd8381f Add a PhiValuesAnalysis pass to calculate the underlying values of phis
This pass is being added in order to make the information available to BasicAA,
which can't do caching of this information itself, but possibly this information
may be useful for other passes.

Incorporates code based on Daniel Berlin's implementation of Tarjan's algorithm.

Differential Revision: https://reviews.llvm.org/D47893

llvm-svn: 335857
2018-06-28 14:13:06 +00:00
Benjamin Kramer 269eb21e1c Revert "Add support for generating a call graph profile from Branch Frequency Info."
This reverts commits r335794 and r335797. Breaks ThinLTO+FDO selfhost.

llvm-svn: 335851
2018-06-28 13:15:03 +00:00
Michael J. Spencer 5bf1ead377 Add support for generating a call graph profile from Branch Frequency Info.
=== Generating the CG Profile ===

The CGProfile module pass simply gets the block profile count for each BB and scans for call instructions.  For each call instruction it adds an edge from the current function to the called function with the current BB block profile count as the weight.

After scanning all the functions, it generates an appending module flag containing the data. The format looks like:
```
!llvm.module.flags = !{!0}

 = !{i32 5, !"CG Profile", !1}
 = !{!2, , !4} ; List of edges
 = !{void ()* @a, void ()* @b, i64 32} ; Edge from a to b with a weight of 32
 = !{void (i1)* @freq, void ()* @a, i64 11}
 = !{void (i1)* @freq, void ()* @b, i64 20}
```

Differential Revision: https://reviews.llvm.org/D48105

llvm-svn: 335794
2018-06-27 23:58:08 +00:00
David Green aee7ad0cde Revert 333358 as it's failing on some builders.
I'm guessing the tests reply on the ARM backend being built.

llvm-svn: 333359
2018-05-27 12:54:33 +00:00
David Green 3034281b43 [UnrollAndJam] Add a new Unroll and Jam pass
This is a simple implementation of the unroll-and-jam classical loop
optimisation.

The basic idea is that we take an outer loop of the form:

for i..
  ForeBlocks(i)
  for j..
    SubLoopBlocks(i, j)
  AftBlocks(i)

Instead of doing normal inner or outer unrolling, we unroll as follows:

for i... i+=2
  ForeBlocks(i)
  ForeBlocks(i+1)
  for j..
    SubLoopBlocks(i, j)
    SubLoopBlocks(i+1, j)
  AftBlocks(i)
  AftBlocks(i+1)
Remainder

So we have unrolled the outer loop, then jammed the two inner loops into
one. This can lead to a simpler inner loop if memory accesses can be shared
between the now-jammed loops.

To do this we have to prove that this is all safe, both for the memory
accesses (using dependence analysis) and that ForeBlocks(i+1) can move before
AftBlocks(i) and SubLoopBlocks(i, j).

Differential Revision: https://reviews.llvm.org/D41953

llvm-svn: 333358
2018-05-27 12:11:21 +00:00
Chandler Carruth e6c30fdda7 Restore the LoopInstSimplify pass, reverting r327329 that removed it.
The plan had always been to move towards using this rather than so much
in-pass simplification within the loop pipeline, but we never got around
to it.... until only a couple months after it was removed due to disuse.
=/

This commit is just a pure revert of the removal. I will add tests and
do some basic cleanup in follow-up commits. Then I'll wire it into the
loop pass pipeline.

Differential Revision: https://reviews.llvm.org/D47353

llvm-svn: 333250
2018-05-25 01:32:36 +00:00
Fedor Sergeev 194a407bda [New PM][IRCE] port of Inductive Range Check Elimination pass to the new pass manager
There are two nontrivial details here:
* Loop structure update interface is quite different with new pass manager,
  so the code to add new loops was factored out

* BranchProbabilityInfo is not a loop analysis, so it can not be just getResult'ed from
  within the loop pass. It cant even be queried through getCachedResult as LoopCanonicalization
  sequence (e.g. LoopSimplify) might invalidate BPI results.

  Complete solution for BPI will likely take some time to discuss and figure out,
  so for now this was partially solved by making BPI optional in IRCE
  (skipping a couple of profitability checks if it is absent).

Most of the IRCE tests got their corresponding new-pass-manager variant enabled.
Only two of them depend on BPI, both marked with TODO, to be turned on when BPI
starts being available for loop passes.

Reviewers: chandlerc, mkazantsev, sanjoy, asbirlea
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D43795

llvm-svn: 327619
2018-03-15 11:01:19 +00:00
Vedant Kumar 3a408538f0 Remove the LoopInstSimplify pass (-loop-instsimplify)
LoopInstSimplify is unused and untested. Reading through the commit
history the pass also seems to have a high maintenance burden.

It would be best to retire the pass for now. It should be easy to
recover if we need something similar in the future.

Differential Revision: https://reviews.llvm.org/D44053

llvm-svn: 327329
2018-03-12 20:49:42 +00:00
Amjad Aboud f1f57a3137 Another try to commit 323321 (aggressive instruction combine).
llvm-svn: 323416
2018-01-25 12:06:32 +00:00
Amjad Aboud d53504e379 Reverted 323321.
llvm-svn: 323326
2018-01-24 14:48:49 +00:00
Amjad Aboud e4453233d7 [InstCombine] Introducing Aggressive Instruction Combine pass (-aggressive-instcombine).
Combine expression patterns to form expressions with fewer, simple instructions.
This pass does not modify the CFG.

For example, this pass reduce width of expressions post-dominated by TruncInst
into smaller width when applicable.

It differs from instcombine pass in that it contains pattern optimization that
requires higher complexity than the O(1), thus, it should run fewer times than
instcombine pass.

Differential Revision: https://reviews.llvm.org/D38313

llvm-svn: 323321
2018-01-24 12:42:42 +00:00
Easwaran Raman bdf20261d8 Add a pass to generate synthetic function entry counts.
Summary:
This pass synthesizes function entry counts by traversing the callgraph
and using the relative block frequencies of the callsites. The intended
use of these counts is in inlining to determine hot/cold callsites in
the absence of profile information.

The pass is split into two files with the code that propagates the
counts in a callgraph in a Utils file. I plan to add support for
propagation in the thinlto link phase and the propagation code will be
shared and hence this split. I did not add support to the old PM since
hot callsite determination in inlining is not possible in old PM
(although we could use hot callee heuristic with synthetic counts in the
old PM it is not worth the effort tuning it)

Reviewers: davidxl, silvas

Subscribers: mgorny, mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D41604

llvm-svn: 322110
2018-01-09 19:39:35 +00:00
Fedor Sergeev 4b86d79048 [PM] port Rewrite Statepoints For GC to the new pass manager.
Summary:
The port is nearly straightforward.
The only complication is related to the analyses handling,
since one of the analyses used in this module pass is domtree,
which is a function analysis. That requires asking for the results
of each function and disallows a single interface for run-on-module
pass action.

Decided to copy-paste the main body of this pass.
Most of its code is requesting analyses anyway, so not that much
of a copy-paste.

The rest of the code movement is to transform all the implementation
helper functions like stripNonValidData into non-member statics.

Extended all the related LLVM tests with new-pass-manager use.
No failures.

Reviewers: sanjoy, anna, reames

Reviewed By: anna

Subscribers: skatkov, llvm-commits

Differential Revision: https://reviews.llvm.org/D41162

llvm-svn: 320796
2017-12-15 09:32:11 +00:00
Chandler Carruth c34f789e38 Add a new pass to speculate around PHI nodes with constant (integer) operands when profitable.
The core idea is to (re-)introduce some redundancies where their cost is
hidden by the cost of materializing immediates for constant operands of
PHI nodes. When the cost of the redundancies is covered by this,
avoiding materializing the immediate has numerous benefits:
1) Less register pressure
2) Potential for further folding / combining
3) Potential for more efficient instructions due to immediate operand

As a motivating example, consider the remarkably different cost on x86
of a SHL instruction with an immediate operand versus a register
operand.

This pattern turns up surprisingly frequently, but is somewhat rarely
obvious as a significant performance problem.

The pass is entirely target independent, but it does rely on the target
cost model in TTI to decide when to speculate things around the PHI
node. I've included x86-focused tests, but any target that sets up its
immediate cost model should benefit from this pass.

There is probably more that can be done in this space, but the pass
as-is is enough to get some important performance on our internal
benchmarks, and should be generally performance neutral, but help with
more extensive benchmarking is always welcome.

One awkward part is that this pass has to be scheduled after
*everything* that can eliminate these kinds of redundancies. This
includes SimplifyCFG, GVN, etc. I'm open to suggestions about better
places to put this. We could in theory make it part of the codegen pass
pipeline, but there doesn't really seem to be a good reason for that --
it isn't "lowering" in any sense and only relies on pretty standard cost
model based TTI queries, so it seems to fit well with the "optimization"
pipeline model. Still, further thoughts on the pipeline position are
welcome.

I've also only implemented this in the new pass manager. If folks are
very interested, I can try to add it to the old PM as well, but I didn't
really see much point (my use case is already switched over to the new
PM).

I've tested this pretty heavily without issue. A wide range of
benchmarks internally show no change outside the noise, and I don't see
any significant changes in SPEC either. However, the size class
computation in tcmalloc is substantially improved by this, which turns
into a 2% to 4% win on the hottest path through tcmalloc for us, so
there are definitely important cases where this is going to make
a substantial difference.

Differential revision: https://reviews.llvm.org/D37467

llvm-svn: 319164
2017-11-28 11:32:31 +00:00
Hans Wennborg e1ecd61b98 Rename CountingFunctionInserter and use for both mcount and cygprofile calls, before and after inlining
Clang implements the -finstrument-functions flag inherited from GCC, which
inserts calls to __cyg_profile_func_{enter,exit} on function entry and exit.

This is useful for getting a trace of how the functions in a program are
executed. Normally, the calls remain even if a function is inlined into another
function, but it is useful to be able to turn this off for users who are
interested in a lower-level trace, i.e. one that reflects what functions are
called post-inlining. (We use this to generate link order files for Chromium.)

LLVM already has a pass for inserting similar instrumentation calls to
mcount(), which it does after inlining. This patch renames and extends that
pass to handle calls both to mcount and the cygprofile functions, before and/or
after inlining as controlled by function attributes.

Differential Revision: https://reviews.llvm.org/D39287

llvm-svn: 318195
2017-11-14 21:09:45 +00:00
Chandler Carruth 00a301d568 [PM] Port BoundsChecking to the new PM.
Registers it and everything, updates all the references, etc.

Next patch will add support to Clang's `-fexperimental-new-pass-manager`
path to actually enable BoundsChecking correctly.

Differential Revision: https://reviews.llvm.org/D39084

llvm-svn: 318128
2017-11-14 01:30:04 +00:00
Jun Bum Lim 0c99007db1 Recommit r317351 : Add CallSiteSplitting pass
This recommit r317351 after fixing a buildbot failure.

Original commit message:

    Summary:
    This change add a pass which tries to split a call-site to pass
    more constrained arguments if its argument is predicated in the control flow
    so that we can expose better context to the later passes (e.g, inliner, jump
    threading, or IPA-CP based function cloning, etc.).
    As of now we support two cases :

    1) If a call site is dominated by an OR condition and if any of its arguments
    are predicated on this OR condition, try to split the condition with more
    constrained arguments. For example, in the code below, we try to split the
    call site since we can predicate the argument (ptr) based on the OR condition.

    Split from :
          if (!ptr || c)
            callee(ptr);
    to :
          if (!ptr)
            callee(null ptr)  // set the known constant value
          else if (c)
            callee(nonnull ptr)  // set non-null attribute in the argument

    2) We can also split a call-site based on constant incoming values of a PHI
    For example,
    from :
          BB0:
           %c = icmp eq i32 %i1, %i2
           br i1 %c, label %BB2, label %BB1
          BB1:
           br label %BB2
          BB2:
           %p = phi i32 [ 0, %BB0 ], [ 1, %BB1 ]
           call void @bar(i32 %p)
    to
          BB0:
           %c = icmp eq i32 %i1, %i2
           br i1 %c, label %BB2-split0, label %BB1
          BB1:
           br label %BB2-split1
          BB2-split0:
           call void @bar(i32 0)
           br label %BB2
          BB2-split1:
           call void @bar(i32 1)
           br label %BB2
          BB2:
           %p = phi i32 [ 0, %BB2-split0 ], [ 1, %BB2-split1 ]

llvm-svn: 317362
2017-11-03 20:41:16 +00:00
Jun Bum Lim 0eb1c2d63a Revert "Add CallSiteSplitting pass"
Revert due to Buildbot failure.

This reverts commit r317351.

llvm-svn: 317353
2017-11-03 19:17:11 +00:00
Jun Bum Lim 2a58933519 Add CallSiteSplitting pass
Summary:
This change add a pass which tries to split a call-site to pass
more constrained arguments if its argument is predicated in the control flow
so that we can expose better context to the later passes (e.g, inliner, jump
threading, or IPA-CP based function cloning, etc.).
As of now we support two cases :

1) If a call site is dominated by an OR condition and if any of its arguments
are predicated on this OR condition, try to split the condition with more
constrained arguments. For example, in the code below, we try to split the
call site since we can predicate the argument (ptr) based on the OR condition.

Split from :
      if (!ptr || c)
        callee(ptr);
to :
      if (!ptr)
        callee(null ptr)  // set the known constant value
      else if (c)
        callee(nonnull ptr)  // set non-null attribute in the argument

2) We can also split a call-site based on constant incoming values of a PHI
For example,
from :
      BB0:
       %c = icmp eq i32 %i1, %i2
       br i1 %c, label %BB2, label %BB1
      BB1:
       br label %BB2
      BB2:
       %p = phi i32 [ 0, %BB0 ], [ 1, %BB1 ]
       call void @bar(i32 %p)
to
      BB0:
       %c = icmp eq i32 %i1, %i2
       br i1 %c, label %BB2-split0, label %BB1
      BB1:
       br label %BB2-split1
      BB2-split0:
       call void @bar(i32 0)
       br label %BB2
      BB2-split1:
       call void @bar(i32 1)
       br label %BB2
      BB2:
       %p = phi i32 [ 0, %BB2-split0 ], [ 1, %BB2-split1 ]

Reviewers: davidxl, huntergr, chandlerc, mcrosier, eraman, davide

Reviewed By: davidxl

Subscribers: sdesmalen, ashutosh.nema, fhahn, mssimpso, aemerson, mgorny, mehdi_amini, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D39137

llvm-svn: 317351
2017-11-03 19:01:57 +00:00
Matthew Simpson cb58558c2f Add CalledValuePropagation pass
This patch adds a new pass for attaching !callees metadata to indirect call
sites. The pass propagates values to call sites by performing an IPSCCP-like
analysis using the generic sparse propagation solver. For indirect call sites
having a small set of possible callees, the attached metadata indicates what
those callees are. The metadata can be used to facilitate optimizations like
intersecting the function attributes of the possible callees, refining the call
graph, performing indirect call promotion, etc.

Differential Revision: https://reviews.llvm.org/D37355

llvm-svn: 316576
2017-10-25 13:40:08 +00:00
Sanjay Patel 6fd4391ddd [DivRempairs] add a pass to optimize div/rem pairs (PR31028)
This is intended to be a superset of the functionality from D31037 (EarlyCSE) but implemented 
as an independent pass, so there's no stretching of scope and feature creep for an existing pass. 
I also proposed a weaker version of this for SimplifyCFG in D30910. And I initially had almost 
this same functionality as an addition to CGP in the motivating example of PR31028:
https://bugs.llvm.org/show_bug.cgi?id=31028

The advantage of positioning this ahead of SimplifyCFG in the pass pipeline is that it can allow 
more flattening. But it needs to be after passes (InstCombine) that could sink a div/rem and
undo the hoisting that is done here.

Decomposing remainder may allow removing some code from the backend (PPC and possibly others).

Differential Revision: https://reviews.llvm.org/D37121 

llvm-svn: 312862
2017-09-09 13:38:18 +00:00