Commit Graph

733 Commits

Author SHA1 Message Date
Sanjay Patel 403cfe5d70 [PassManager] unify late simplifycfg options between regular and LTO pipelines
This is split off from D102002, and I think it is clear that
the difference in behavior was not intended. Options were
added to SimplifyCFG over time, but different chunks of
the pass pipelines were not kept in sync.
2021-05-28 13:06:49 -04:00
eopXD fa488ea864 [LoopNest][LoopFlatten] Change LoopFlattenPass to LoopNest pass
This patch changes LoopFlattenPass from FunctionPass to LoopNestPass.

Utilize LoopNest and let function 'Flatten' generate information from it.

Reviewed By: Whitney

Differential Revision: https://reviews.llvm.org/D102904
2021-05-28 15:43:12 +00:00
eopXD e96d6f4821 Revert "[LoopNest][LoopFlatten] Change LoopFlattenPass to LoopNest pass"
This reverts commit 7952ddb21f.

Differential Revision: https://reviews.llvm.org/D103302
2021-05-28 07:58:06 +00:00
eopXD 7e06cf8f1b Revert "[LoopNest][LoopFlatten] Change LoopFlattenPass to LoopNest pass"
This reverts commit ffc4d3e068.
2021-05-28 07:48:04 +00:00
eopXD ffc4d3e068 [LoopNest][LoopFlatten] Change LoopFlattenPass to LoopNest pass
This patch changes LoopFlattenPass from FunctionPass to LoopNestPass.

Utilize LoopNest and let function 'Flatten' generate information from it.

Reviewed By: Whitney

Differential Revision: https://reviews.llvm.org/D102904
2021-05-28 07:25:53 +00:00
eopXD 7952ddb21f [LoopNest][LoopFlatten] Change LoopFlattenPass to LoopNest pass
This patch changes LoopFlattenPass from FunctionPass to LoopNestPass.

Utilize LoopNest and let function 'Flatten' generate information from it.

Reviewed By: Whitney

Differential Revision: https://reviews.llvm.org/D102904
2021-05-28 07:11:26 +00:00
maekawatoshiki 2165360003 [LoopUnrollAndJam] Change LoopUnrollAndJamPass to LoopNest pass
This patch changes LoopUnrollAndJamPass from FunctionPass to LoopNest pass.
The next patch will utilize LoopNest to effectively handle loop nests.

Reviewed By: Whitney

Differential Revision: https://reviews.llvm.org/D99149
2021-05-28 01:17:23 +09:00
Jamie Schmeiser 3879fcdb87 Reuse temporary files for print-changed=diff
Summary:
Make the file name and descriptors static so that they are reused by
print-changed=diff. This avoids errors about being unable to create
temporary files when doing the later comparisons in a large compile.

Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: aeubanks (Arthur Eubanks)
Differential Revision: https://reviews.llvm.org/D100116
2021-05-27 10:19:13 -04:00
maekawatoshiki e77d24f70a Revert "[LoopUnrollAndJam] Change LoopUnrollAndJamPass to LoopNest pass"
This reverts commit d65c32fb41.
2021-05-25 11:39:49 +09:00
maekawatoshiki d65c32fb41 [LoopUnrollAndJam] Change LoopUnrollAndJamPass to LoopNest pass
This patch changes LoopUnrollAndJamPass from FunctionPass to LoopNest pass.
The next patch will utilize LoopNest to effectively handle loop nests.

Reviewed By: Whitney

Differential Revision: https://reviews.llvm.org/D99149
2021-05-23 22:32:01 +09:00
Arthur Eubanks a52530dd6a Revert "[NPM] Do not run function simplification pipeline unnecessarily"
This reverts commit 97ab068034.

Depends on D100917, which is to be reverted.
2021-05-21 16:38:02 -07:00
maekawatoshiki fd53cb4148 Revert "[LoopUnrollAndJam] Change LoopUnrollAndJamPass to LoopNest pass"
This reverts commit cea7a3fe3d.
To investigate sanitizer-x86_64-linux-fast failure.
2021-05-22 01:40:43 +09:00
maekawatoshiki cea7a3fe3d [LoopUnrollAndJam] Change LoopUnrollAndJamPass to LoopNest pass
This patch changes LoopUnrollAndJamPass from FunctionPass to LoopNest pass.
The next patch will utilize LoopNest to effectively handle loop nests.

Reviewed By: Whitney

Differential Revision: https://reviews.llvm.org/D99149
2021-05-21 23:57:39 +09:00
Arthur Eubanks 0c509dbc7e [NewPM] Add options to PrintPassInstrumentation
To bring D99599's implementation in line with the existing
PrintPassInstrumentation, and to fix a FIXME, add more customizability
to PrintPassInstrumentation.

Introduce three new options. The first takes over the existing
"-debug-pass-manager-verbose" cl::opt.

The second and third option are specific to -fdebug-pass-structure. They
allow indentation, and also don't print analysis queries.

To avoid more golden file tests than necessary, prune down the
-fdebug-pass-structure tests.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D102196
2021-05-18 20:59:35 -07:00
Mats Larsen 0c557db617 [NewPM] Add C bindings for new pass manager
This patch contains the bare minimum to run the new Pass Manager from the LLVM-C APIs. It does not feature PGOOptions, PassPlugins or Debugify in its current state. Bugzilla: PR48499

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D102136
2021-05-17 11:45:47 -07:00
Nico Weber 0b33977872 Revert "[NewPM] Add C bindings for new pass manager"
This reverts commit cd220a0678.
Doesn't build.
2021-05-17 13:59:12 -04:00
Mats Larsen cd220a0678 [NewPM] Add C bindings for new pass manager
This patch contains the bare minimum to run the new Pass Manager from the LLVM-C APIs. It does not feature PGOOptions, PassPlugins or Debugify in its current state. Bugzilla: PR48499

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D102136
2021-05-17 10:48:45 -07:00
Nikita Popov fb9ed1979a [IR] Add BasicBlock::isEntryBlock() (NFC)
This is a recurring and somewhat awkward pattern. Add a helper
method for it.
2021-05-15 12:41:58 +02:00
Florian Hahn 860b37526a [Passes] Run GlobalsAA before LICM during LTO in new PM.
This patch adjusts the LTO pipeline in the new PM to run GlobalsAA
before LICM to match the legacy PM.

This fixes a regression where the new PM failed to vectorize loops that
require hoisting/sinking by LICM depending on GlobalsAA info.

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D102345
2021-05-13 13:11:18 +01:00
Florian Hahn 3eaf235855 [Passes] Use MemorySSA for LICM during LTO.
Split off from D102345 to commit this separately from other changes in
the patch. This aligns the behavior of the new PM with the legacy PM
for LTO, with respect to running LICM.

Together with the remaining changes in D102345, this fixes new PM
regressions where we fail to vectorize loops that are vectorized with
the legacy PM.
2021-05-13 12:16:41 +01:00
Sanjay Patel 88d8f10baf [PassManager] add helper function to hold set of vector passes (2nd try)
This is better no-functional-change-intended than the 1st attempt.
As noted in D102002, there were at least 2 diffs that went
unchecked in pass manager regressions tests: different pass
parameters (SimplifyCFG) and an extension point/callback.
Those should be lifted from the original code blocks correctly
now.
2021-05-10 14:43:00 -04:00
Sanjay Patel 822be4bec8 Revert "[PassManager] add helper function to hold set of vector passes"
This reverts commit fefcb1f878.
It was supposed to be NFC, but as noted in the post-commit
comments in D102002, that was not true: SimplifyCFG uses
different parameters and there's a difference in an
extension point / callback.
2021-05-10 10:59:30 -04:00
Arthur Eubanks 34a8a437bf [NewPM] Hide pass manager debug logging behind -debug-pass-manager-verbose
Printing pass manager invocations is fairly verbose and not super
useful.

This allows us to remove DebugLogging from pass managers and PassBuilder
since all logging (aside from analysis managers) goes through
instrumentation now.

This has the downside of never being able to print the top level pass
manager via instrumentation, but that seems like a minor downside.

Reviewed By: ychen

Differential Revision: https://reviews.llvm.org/D101797
2021-05-07 21:51:47 -07:00
Arthur Eubanks 6f7131002b [NewPM] Move analysis invalidation/clearing logging to instrumentation
We're trying to move DebugLogging into instrumentation, rather than
being part of PassManagers/AnalysisManagers.

Reviewed By: ychen

Differential Revision: https://reviews.llvm.org/D102093
2021-05-07 15:25:31 -07:00
Fangrui Song d8aba75a76 Internalize some cl::opt global variables or move them under namespace llvm 2021-05-07 11:15:43 -07:00
Sanjay Patel fefcb1f878 [PassManager] add helper function to hold set of vector passes
This is no-functional-change-intended (NFC) and split off from
D102002 (which proposes to eliminate the LTO-based differences).
2021-05-06 15:36:15 -04:00
Mircea Trofin 97ab068034 [NPM] Do not run function simplification pipeline unnecessarily
The CGSCC pass manager interplay with the FunctionAnalysisManagerCGSCCProxy is 'special' in the sense that the former will rerun the latter if there are changes to a SCC structure; that being said, some of the functions in the SCC may be unchanged. In that case, the function simplification pipeline will be re-run, which impacts compile time[1].

This patch allows the function simplification pipeline be skipped if it was already run and the function was not modified since.

The behavior is currently disabled by default. This is because, currently, the rerunning of the function simplification pipeline on an unchanged function may still result in changes. The patch simplifies investigating and fixing those cases where repeated function pass runs do actually positively impact code quality, while offering an easy workaround for those impacted negatively by compile time regressions, and not impacting mainline scenarios.

[1] A [[ http://llvm-compile-time-tracker.com/compare.php?from=eb37d3546cd0c6e67798496634c45e501f7806f1&to=ac722d1190dc7bbdd17e977ef7ec95e69eefc91e&stat=instructions | compile time tracker ]] run with the option enabled.

Differential Revision: https://reviews.llvm.org/D98103
2021-05-06 12:24:33 -07:00
Arthur Eubanks 2df3426fd1 [NewPM] Invalidate AAManager after populating GlobalsAA
GlobalsAA is only created at the beginning of the inliner pipeline.  If
an AAManager is cached from previous passes, it won't get rebuilt to
include the newly created GlobalsAA.

Reviewed By: mtrofin

Differential Revision: https://reviews.llvm.org/D101379
2021-05-03 16:37:32 -07:00
Gulfem Savrun Yeniceri 4423a7a09b [NewPM] Disable RelLookupTableConverter pass in LTO
Relative look table converter pass caused an issue when full lto
is enabled (reported in https://reviews.llvm.org/D94355).
This patch disables that pass from full lto pre-link phase optimization
pipeline until the issue is fixed.

Differential Revision: https://reviews.llvm.org/D101664
2021-04-30 21:23:40 +00:00
Florian Hahn ed9df5bd2f
[Passes] Run sinking/hoisting in SimplifyCFG earlier.
Hoisting and sinking instructions out of conditional blocks enables
additional vectorization by:

1. Executing memory accesses unconditionally.
2. Reducing the number of instructions that need predication.

After disabling early hoisting / sinking, we miss out on a few
vectorization opportunities. One of those is causing a ~10% performance
regression in one of the Geekbench benchmarks on AArch64.

This patch tires to recover the regression by running hoisting/sinking
as part of a SimplifyCFG run after LoopRotate and before LoopVectorize.

Note that in the legacy pass-manager, we run LoopRotate just before
vectorization again and there's no SimplifyCFG run in between, so the
sinking/hoisting may impact the later run on LoopRotate. But the impact
should be limited and the benefit of hosting/sinking at this stage
should outweigh the risk of not rotating.

Compile-time impact looks slightly positive for most cases.
http://llvm-compile-time-tracker.com/compare.php?from=2ea7fb7b1c045a7d60fcccf3df3ebb26aa3699e5&to=e58b4a763c691da651f25996aad619cb3d946faf&stat=instructions

NewPM-O3: geomean -0.19%
NewPM-ReleaseThinLTO: geoman -0.54%
NewPM-ReleaseLTO-g: geomean -0.03%

With a few benchmarks seeing a notable increase, but also some
improvements.

Alternative to D101290.

Reviewed By: lebedev.ri

Differential Revision: https://reviews.llvm.org/D101468
2021-04-30 12:23:57 +01:00
Evgeny Leviant 6a0283d0d2 [NewPM] Add an option to dump pass structure
Patch adds -debug-pass-structure option to dump pass structure when
new pass manager is used.

Differential revision: https://reviews.llvm.org/D99599
2021-04-29 10:29:42 +03:00
Arthur Eubanks 1dfb52a756 [NewPM] Mark some more wrapper passes as ignored
We shouldn't print IR when seeing these passes.
2021-04-21 23:55:02 -07:00
Joseph Huber b2ad63d3cf [OpenMP] Add OpenMPOpt as a Module pass
Summary:
This patch registers OpenMPOpt as a Module pass in addition to a CGSCC
pass. This is so certain optimzations that are sensitive to intact
call-sites can happen before inlining. The old `openmpopt` pass name is
changed to `openmp-opt-cgscc` and `openmp-opt` calls the Module pass.
The current module pass only runs a single check but will be expanded in
the future.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D99202
2021-04-20 12:28:58 -04:00
Arthur Eubanks c8f0a7c215 [NewPM] Cleanup IR printing instrumentation
Being lazy with printing the banner seems hard to reason with, we should print it
unconditionally first (it could also lead to duplicate banners if we
have multiple functions in -filter-print-funcs).

The printIR() functions were doing too many things. I separated out the
call from PrintPassInstrumentation since we were essentially doing two
completely separate things in printIR() from different callers.

There were multiple ways to generate the name of some IR. That's all
been moved to getIRName(). The printing of the IR name was also
inconsistent, now it's always "IR Dump on $foo" where "$foo" is the
name. For a function, it's the function name. For a loop, it's what's
printed by Loop::print(), which is more detailed. For an SCC, it's the
list of functions in parentheses. For a module it's "[module]", to
differentiate between a possible SCC with a function called "module".

To preserve D74814, we have to check if we're going to print anything at
all first. This is unfortunate, but I would consider this a special
case that shouldn't be handled in the core logic.

Reviewed By: jamieschmeiser

Differential Revision: https://reviews.llvm.org/D100231
2021-04-15 09:50:55 -07:00
Gulfem Savrun Yeniceri e96df3e531 [Passes] Add relative lookup table converter pass
Lookup tables generate non PIC-friendly code, which requires dynamic relocation as described in:
https://bugs.llvm.org/show_bug.cgi?id=45244

This patch adds a new pass that converts lookup tables to relative lookup tables to make them PIC-friendly.

Differential Revision: https://reviews.llvm.org/D94355
2021-04-13 01:29:41 +00:00
Sanjay Patel 661cc71a1c [PassManager][PhaseOrdering] lower expects before running simplifyCFG
Retry of 330619a3a6 that includes a clang test update.

Original commit message:

If we run passes before lowering llvm.expect intrinsics to metadata,
then those passes have no way to act on the hints provided by llvm.expect.
SimplifyCFG is the known offender, and we made it smarter about profile
metadata in D98898 <https://reviews.llvm.org/D98898>.

In the motivating example from https://llvm.org/PR49336 , this means we
were ignoring the recommended method for a programmer to tell the compiler
that a compare+branch is expensive. This change appears to solve that case -
the metadata survives to the backend, the compare order is as expected in IR,
and the backend does not do anything to reverse it.

We make the same change to the old pass manager to keep things synchronized.

Differential Revision: https://reviews.llvm.org/D100213
2021-04-12 15:07:53 -04:00
Arthur Eubanks be00edfee5 [NewPM] Fix -print-changed when a -filter-print-funcs function is removed
-filter-print-funcs -print-changed was crashing after the filter func
was removed by a pass with
  Assertion failed: After.find("*** IR Dump") == 0 && "Unexpected banner format."
We weren't printing the banner because when we have -filter-print-funcs,
we print each function separately, letting the print function filter out
unwanted functions.

Reviewed By: jamieschmeiser

Differential Revision: https://reviews.llvm.org/D100237
2021-04-12 11:55:17 -07:00
Sanjay Patel 23ac9d1e6e Revert "[PassManager][PhaseOrdering] lower expects before running simplifyCFG"
This reverts commit 330619a3a6.
There are clang tests that also need to be updated.
2021-04-12 13:58:54 -04:00
Sanjay Patel 330619a3a6 [PassManager][PhaseOrdering] lower expects before running simplifyCFG
If we run passes before lowering llvm.expect intrinsics to metadata,
then those passes have no way to act on the hints provided by llvm.expect.
SimplifyCFG is the known offender, and we made it smarter about profile
metadata in D98898.

In the motivating example from https://llvm.org/PR49336 , this means we
were ignoring the recommended method for a programmer to tell the compiler
that a compare+branch is expensive. This change appears to solve that case -
the metadata survives to the backend, the compare order is as expected in IR,
and the backend does not do anything to reverse it.

We make the same change to the old pass manager to keep things synchronized.

Differential Revision: https://reviews.llvm.org/D100213
2021-04-12 12:23:31 -04:00
Jingu Kang 798b0fd36b [NPM] Fix typo inisLTOPreLink for loop rotate
Differential Revision: https://reviews.llvm.org/D100033
2021-04-07 15:08:37 +01:00
Yevgeny Rouban b5c63e30ca [NewPM] Set verify-cfg-preserved=1 by default for debug builds 2021-04-07 08:34:30 +07:00
Fangrui Song a7ef45bc5c [NewPM] Fix -Wunused-lambda-capture in -DLLVM_ENABLE_ASSERTIONS=off builds after D91327 2021-04-06 11:30:20 -07:00
Yevgeny Rouban 98742e42fc [NewPM] Fix unused lambda capture build error
Fixes commit 39e3e3aa51d: Redesign of PreserveCFG Checker
2021-04-06 13:14:16 +07:00
Yevgeny Rouban 39e3e3aa51 [NewPM] Redesign of PreserveCFG Checker
The reason for the NewPM redesign is described in the commit
  cba3e783389a: [NewPM] Disable PreservedCFGChecker ...

The checker introduces an internal custom CFG analysis that tracks
current up-to date CFG snapshot. The analysis is invalidated along
any other CFG related analysis (the key is CFGAnalyses). If the CFG
analysis is not invalidated at a functional pass exit then the checker
asserts that the CFG snapshot taken from this analysis is equals to
a snapshot of the current CFG.

Along the way:
- the function CFG::printDiff() is simplified by removing function
  name calculation. The name is printed by the caller;
- fixed CFG invalidated condition (see CFG::invalidate());
- StandardInstrumentations::registerCallbacks() gets additional
  optional parameter of type FunctionAnalysisManager*, which is
  needed by the checker to get the custom CFG analysis;
- several PM related tests updated to explicitly set
  -verify-cfg-preserved=1 as they need.

This patch is safe to land as the CFGChecker is left switched off
(the options -verify-cfg-preserved is false by default). It will be
switched on by a separate patch to minimize possible reverts.

Reviewed By: skatkov, kuhar

Differential Revision: https://reviews.llvm.org/D91327
2021-04-06 12:35:49 +07:00
Roman Lebedev a26f1bf67e
[PassManager] Run additional LICM before LoopRotate
Loop rotation often has to perform code duplication
from header into preheader, which introduces PHI nodes.

>>! In D99204, @thopre wrote:
>
> With loop peeling, it is important that unnecessary PHIs be avoided or
> it will leads to spurious peeling. One source of such PHIs is loop
> rotation which creates PHIs for invariant loads. Those PHIs are
> particularly problematic since loop peeling is now run as part of simple
> loop unrolling before GVN is run, and are thus a source of spurious
> peeling.
>
> Note that while some of the load can be hoisted and eventually
> eliminated by instruction combine, this is not always possible due to
> alignment issue. In particular, the motivating example [1] was a load
> inside a class instance which cannot be hoisted because the `this'
> pointer has an alignment of 1.
>
> [1] http://lists.llvm.org/pipermail/llvm-dev/attachments/20210312/4ce73c47/attachment.cpp

Now, we could enhance LoopRotate to avoid duplicating code when not needed,
but instead hoist loop-invariant code, but isn't that a code duplication? (*sic*)
We have LICM, and in fact we already run it right after LoopRotation.

We could try to move it to before LoopRotation,
that is basically free from compile-time perspective:
https://llvm-compile-time-tracker.com/compare.php?from=6c93eb4477d88af046b915bc955c03693b2cbb58&to=a4bee6d07732b1184c436da489040b912f0dc271&stat=instructions
But, looking at stats, i think it isn't great that we would no longer do LICM after LoopRotation, in particular:
| statistic name                                   | LoopRotate-LICM | LICM-LoopRotate |     Δ |       % | abs(%) |
| asm-printer.EmittedInsts                         | 9015930         | 9015799         |  -131 |   0.00% |  0.00% |
| indvars.NumElimCmp                               | 3536            | 3544            |     8 |   0.23% |  0.23% |
| indvars.NumElimExt                               | 36725           | 36580           |  -145 |  -0.39% |  0.39% |
| indvars.NumElimIV                                | 1197            | 1187            |   -10 |  -0.84% |  0.84% |
| indvars.NumElimIdentity                          | 143             | 136             |    -7 |  -4.90% |  4.90% |
| indvars.NumElimRem                               | 4               | 5               |     1 |  25.00% | 25.00% |
| indvars.NumLFTR                                  | 29842           | 29890           |    48 |   0.16% |  0.16% |
| indvars.NumReplaced                              | 2293            | 2227            |   -66 |  -2.88% |  2.88% |
| indvars.NumSimplifiedSDiv                        | 6               | 8               |     2 |  33.33% | 33.33% |
| indvars.NumWidened                               | 26438           | 26329           |  -109 |  -0.41% |  0.41% |
| instcount.TotalBlocks                            | 1178338         | 1173840         | -4498 |  -0.38% |  0.38% |
| instcount.TotalFuncs                             | 111825          | 111829          |     4 |   0.00% |  0.00% |
| instcount.TotalInsts                             | 9905442         | 9896139         | -9303 |  -0.09% |  0.09% |
| lcssa.NumLCSSA                                   | 425871          | 423961          | -1910 |  -0.45% |  0.45% |
| licm.NumHoisted                                  | 378357          | 378753          |   396 |   0.10% |  0.10% |
| licm.NumMovedCalls                               | 2193            | 2208            |    15 |   0.68% |  0.68% |
| licm.NumMovedLoads                               | 35899           | 31821           | -4078 | -11.36% | 11.36% |
| licm.NumPromoted                                 | 11178           | 11154           |   -24 |  -0.21% |  0.21% |
| licm.NumSunk                                     | 13359           | 13587           |   228 |   1.71% |  1.71% |
| loop-delete.NumDeleted                           | 8547            | 8402            |  -145 |  -1.70% |  1.70% |
| loop-instsimplify.NumSimplified                  | 12876           | 11890           |  -986 |  -7.66% |  7.66% |
| loop-peel.NumPeeled                              | 1008            | 925             |   -83 |  -8.23% |  8.23% |
| loop-rotate.NumNotRotatedDueToHeaderSize         | 368             | 365             |    -3 |  -0.82% |  0.82% |
| loop-rotate.NumRotated                           | 42015           | 42003           |   -12 |  -0.03% |  0.03% |
| loop-simplifycfg.NumLoopBlocksDeleted            | 240             | 242             |     2 |   0.83% |  0.83% |
| loop-simplifycfg.NumLoopExitsDeleted             | 497             | 20              |  -477 | -95.98% | 95.98% |
| loop-simplifycfg.NumTerminatorsFolded            | 618             | 336             |  -282 | -45.63% | 45.63% |
| loop-unroll.NumCompletelyUnrolled                | 11028           | 11032           |     4 |   0.04% |  0.04% |
| loop-unroll.NumUnrolled                          | 12608           | 12529           |   -79 |  -0.63% |  0.63% |
| mem2reg.NumDeadAlloca                            | 10222           | 10221           |    -1 |  -0.01% |  0.01% |
| mem2reg.NumPHIInsert                             | 192110          | 192106          |    -4 |   0.00% |  0.00% |
| mem2reg.NumSingleStore                           | 637650          | 637643          |    -7 |   0.00% |  0.00% |
| scalar-evolution.NumBruteForceTripCountsComputed | 814             | 812             |    -2 |  -0.25% |  0.25% |
| scalar-evolution.NumTripCountsComputed           | 283108          | 282934          |  -174 |  -0.06% |  0.06% |
| scalar-evolution.NumTripCountsNotComputed        | 106712          | 106718          |     6 |   0.01% |  0.01% |
| simple-loop-unswitch.NumBranches                 | 5178            | 4752            |  -426 |  -8.23% |  8.23% |
| simple-loop-unswitch.NumCostMultiplierSkipped    | 914             | 503             |  -411 | -44.97% | 44.97% |
| simple-loop-unswitch.NumSwitches                 | 20              | 18              |    -2 | -10.00% | 10.00% |
| simple-loop-unswitch.NumTrivial                  | 183             | 95              |   -88 | -48.09% | 48.09% |

... but that actually regresses LICM (-12% `licm.NumMovedLoads`),
loop-simplifycfg (`NumLoopExitsDeleted`, `NumTerminatorsFolded`),
simple-loop-unswitch (`NumTrivial`).

What if we instead have LICM both before and after LoopRotate?
| statistic name                                | LoopRotate-LICM | LICM-LoopRotate-LICM |     Δ |       % | abs(%) |
| asm-printer.EmittedInsts                      | 9015930         | 9014474              | -1456 |  -0.02% |  0.02% |
| indvars.NumElimCmp                            | 3536            | 3546                 |    10 |   0.28% |  0.28% |
| indvars.NumElimExt                            | 36725           | 36681                |   -44 |  -0.12% |  0.12% |
| indvars.NumElimIV                             | 1197            | 1185                 |   -12 |  -1.00% |  1.00% |
| indvars.NumElimIdentity                       | 143             | 146                  |     3 |   2.10% |  2.10% |
| indvars.NumElimRem                            | 4               | 5                    |     1 |  25.00% | 25.00% |
| indvars.NumLFTR                               | 29842           | 29899                |    57 |   0.19% |  0.19% |
| indvars.NumReplaced                           | 2293            | 2299                 |     6 |   0.26% |  0.26% |
| indvars.NumSimplifiedSDiv                     | 6               | 8                    |     2 |  33.33% | 33.33% |
| indvars.NumWidened                            | 26438           | 26404                |   -34 |  -0.13% |  0.13% |
| instcount.TotalBlocks                         | 1178338         | 1173652              | -4686 |  -0.40% |  0.40% |
| instcount.TotalFuncs                          | 111825          | 111829               |     4 |   0.00% |  0.00% |
| instcount.TotalInsts                          | 9905442         | 9895452              | -9990 |  -0.10% |  0.10% |
| lcssa.NumLCSSA                                | 425871          | 425373               |  -498 |  -0.12% |  0.12% |
| licm.NumHoisted                               | 378357          | 383352               |  4995 |   1.32% |  1.32% |
| licm.NumMovedCalls                            | 2193            | 2204                 |    11 |   0.50% |  0.50% |
| licm.NumMovedLoads                            | 35899           | 35755                |  -144 |  -0.40% |  0.40% |
| licm.NumPromoted                              | 11178           | 11163                |   -15 |  -0.13% |  0.13% |
| licm.NumSunk                                  | 13359           | 14321                |   962 |   7.20% |  7.20% |
| loop-delete.NumDeleted                        | 8547            | 8538                 |    -9 |  -0.11% |  0.11% |
| loop-instsimplify.NumSimplified               | 12876           | 12041                |  -835 |  -6.48% |  6.48% |
| loop-peel.NumPeeled                           | 1008            | 924                  |   -84 |  -8.33% |  8.33% |
| loop-rotate.NumNotRotatedDueToHeaderSize      | 368             | 365                  |    -3 |  -0.82% |  0.82% |
| loop-rotate.NumRotated                        | 42015           | 42005                |   -10 |  -0.02% |  0.02% |
| loop-simplifycfg.NumLoopBlocksDeleted         | 240             | 241                  |     1 |   0.42% |  0.42% |
| loop-simplifycfg.NumTerminatorsFolded         | 618             | 619                  |     1 |   0.16% |  0.16% |
| loop-unroll.NumCompletelyUnrolled             | 11028           | 11029                |     1 |   0.01% |  0.01% |
| loop-unroll.NumUnrolled                       | 12608           | 12525                |   -83 |  -0.66% |  0.66% |
| mem2reg.NumPHIInsert                          | 192110          | 192073               |   -37 |  -0.02% |  0.02% |
| mem2reg.NumSingleStore                        | 637650          | 637652               |     2 |   0.00% |  0.00% |
| scalar-evolution.NumTripCountsComputed        | 283108          | 282998               |  -110 |  -0.04% |  0.04% |
| scalar-evolution.NumTripCountsNotComputed     | 106712          | 106691               |   -21 |  -0.02% |  0.02% |
| simple-loop-unswitch.NumBranches              | 5178            | 5185                 |     7 |   0.14% |  0.14% |
| simple-loop-unswitch.NumCostMultiplierSkipped | 914             | 925                  |    11 |   1.20% |  1.20% |
| simple-loop-unswitch.NumTrivial               | 183             | 179                  |    -4 |  -2.19% |  2.19% |
| simple-loop-unswitch.NumBranches              | 5178            | 4752                 |  -426 |  -8.23% |  8.23% |
| simple-loop-unswitch.NumCostMultiplierSkipped | 914             | 503                  |  -411 | -44.97% | 44.97% |
| simple-loop-unswitch.NumSwitches              | 20              | 18                   |    -2 | -10.00% | 10.00% |
| simple-loop-unswitch.NumTrivial               | 183             | 95                   |   -88 | -48.09% | 48.09% |

I.e. we end up with less instructions, less peeling, more LICM activity,
also note how none of those 4 regressions are here. Namely:

| statistic name                                   | LICM-LoopRotate | LICM-LoopRotate-LICM |     Δ |        % |   abs(%) |
| asm-printer.EmittedInsts                         | 9015799         | 9014474              | -1325 |   -0.01% |    0.01% |
| indvars.NumElimCmp                               | 3544            | 3546                 |     2 |    0.06% |    0.06% |
| indvars.NumElimExt                               | 36580           | 36681                |   101 |    0.28% |    0.28% |
| indvars.NumElimIV                                | 1187            | 1185                 |    -2 |   -0.17% |    0.17% |
| indvars.NumElimIdentity                          | 136             | 146                  |    10 |    7.35% |    7.35% |
| indvars.NumLFTR                                  | 29890           | 29899                |     9 |    0.03% |    0.03% |
| indvars.NumReplaced                              | 2227            | 2299                 |    72 |    3.23% |    3.23% |
| indvars.NumWidened                               | 26329           | 26404                |    75 |    0.28% |    0.28% |
| instcount.TotalBlocks                            | 1173840         | 1173652              |  -188 |   -0.02% |    0.02% |
| instcount.TotalInsts                             | 9896139         | 9895452              |  -687 |   -0.01% |    0.01% |
| lcssa.NumLCSSA                                   | 423961          | 425373               |  1412 |    0.33% |    0.33% |
| licm.NumHoisted                                  | 378753          | 383352               |  4599 |    1.21% |    1.21% |
| licm.NumMovedCalls                               | 2208            | 2204                 |    -4 |   -0.18% |    0.18% |
| licm.NumMovedLoads                               | 31821           | 35755                |  3934 |   12.36% |   12.36% |
| licm.NumPromoted                                 | 11154           | 11163                |     9 |    0.08% |    0.08% |
| licm.NumSunk                                     | 13587           | 14321                |   734 |    5.40% |    5.40% |
| loop-delete.NumDeleted                           | 8402            | 8538                 |   136 |    1.62% |    1.62% |
| loop-instsimplify.NumSimplified                  | 11890           | 12041                |   151 |    1.27% |    1.27% |
| loop-peel.NumPeeled                              | 925             | 924                  |    -1 |   -0.11% |    0.11% |
| loop-rotate.NumRotated                           | 42003           | 42005                |     2 |    0.00% |    0.00% |
| loop-simplifycfg.NumLoopBlocksDeleted            | 242             | 241                  |    -1 |   -0.41% |    0.41% |
| loop-simplifycfg.NumLoopExitsDeleted             | 20              | 497                  |   477 | 2385.00% | 2385.00% |
| loop-simplifycfg.NumTerminatorsFolded            | 336             | 619                  |   283 |   84.23% |   84.23% |
| loop-unroll.NumCompletelyUnrolled                | 11032           | 11029                |    -3 |   -0.03% |    0.03% |
| loop-unroll.NumUnrolled                          | 12529           | 12525                |    -4 |   -0.03% |    0.03% |
| mem2reg.NumDeadAlloca                            | 10221           | 10222                |     1 |    0.01% |    0.01% |
| mem2reg.NumPHIInsert                             | 192106          | 192073               |   -33 |   -0.02% |    0.02% |
| mem2reg.NumSingleStore                           | 637643          | 637652               |     9 |    0.00% |    0.00% |
| scalar-evolution.NumBruteForceTripCountsComputed | 812             | 814                  |     2 |    0.25% |    0.25% |
| scalar-evolution.NumTripCountsComputed           | 282934          | 282998               |    64 |    0.02% |    0.02% |
| scalar-evolution.NumTripCountsNotComputed        | 106718          | 106691               |   -27 |   -0.03% |    0.03% |
| simple-loop-unswitch.NumBranches                 | 4752            | 5185                 |   433 |    9.11% |    9.11% |
| simple-loop-unswitch.NumCostMultiplierSkipped    | 503             | 925                  |   422 |   83.90% |   83.90% |
| simple-loop-unswitch.NumSwitches                 | 18              | 20                   |     2 |   11.11% |   11.11% |
| simple-loop-unswitch.NumTrivial                  | 95              | 179                  |    84 |   88.42% |   88.42% |

{F15983613} {F15983615} {F15983616}
(this is vanilla llvm testsuite + rawspeed + darktable)

As an example of the code where early LICM only is bad, see:
https://godbolt.org/z/GzEbacs4K

This does have an observable compile-time regression of +~0.5% geomean
https://llvm-compile-time-tracker.com/compare.php?from=7c5222e4d1a3a14f029e5f614c9aefd0fa505f1e&to=5d81826c3411982ca26e46b9d0aff34c80577664&stat=instructions
but i think that's basically nothing, and there's potential that it might
be avoidable in the future by fixing clang to produce alignment information
on function arguments, thus making the second run unneeded.

Differential Revision: https://reviews.llvm.org/D99249
2021-04-02 11:11:42 +03:00
Krasimir Georgiev c51e91e046 Revert "[Passes] Add relative lookup table converter pass"
This reverts commit 5178ffc7cf.

Compiling `llvm-profdata` with a compiler build from this produces a
crashing binary.
2021-03-30 14:13:37 +02:00
Gulfem Savrun Yeniceri 5178ffc7cf [Passes] Add relative lookup table converter pass
Lookup tables generate non PIC-friendly code, which requires dynamic relocation as described in:
https://bugs.llvm.org/show_bug.cgi?id=45244

This patch adds a new pass that converts lookup tables to relative lookup tables to make them PIC-friendly.

Differential Revision: https://reviews.llvm.org/D94355
2021-03-29 21:53:32 +00:00
Jamie Schmeiser 7f2ae3d55f add print-change diff modes that do not use colour
Summary:
The colour characters currently added to the output of -print-changed=diff
and -print-changed=diff-quiet cause difficulties when capturing the output
and examining it in an editor. Change the function to not have the colour
characters and add 2 new choices (-print-changed=cdiff and
-print-changed=cdiff-quiet) to retain the existing functionality of adding
the colour characters.

Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: aeubanks (Arthur Eubanks) yrouban (Yevgeny Rouban)
Differential Revision: https://reviews.llvm.org/D97398
2021-03-25 10:35:27 -04:00
Gulfem Savrun Yeniceri 5fbe1fdf17 Revert "[Passes] Add relative lookup table converter pass"
This reverts commit 5fd001a5ff
because it broke clang-with-thin-lto-ubuntu bot.
2021-03-24 18:59:33 +00:00
Gulfem Savrun Yeniceri 5fd001a5ff [Passes] Add relative lookup table converter pass
Lookup tables generate non PIC-friendly code, which requires dynamic relocation as described in:
https://bugs.llvm.org/show_bug.cgi?id=45244

This patch adds a new pass that converts lookup tables to relative lookup tables to make them PIC-friendly.

Differential Revision: https://reviews.llvm.org/D94355
2021-03-24 17:31:18 +00:00