2020-01-14 03:09:13 +08:00
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; Validate ThinLTO post link pipeline when we have instrumentation PGO
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;
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; Postlink pipelines:
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2021-04-06 12:31:07 +08:00
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; RUN: opt -disable-verify -verify-cfg-preserved=0 -debug-pass-manager \
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2020-01-14 03:09:13 +08:00
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; RUN: -passes='thinlto<O1>' -S %s 2>&1 \
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2020-10-30 12:54:45 +08:00
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; RUN: | FileCheck %s --check-prefixes=CHECK-O,CHECK-O1,%llvmcheckext
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2021-04-06 12:31:07 +08:00
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; RUN: opt -disable-verify -verify-cfg-preserved=0 -debug-pass-manager \
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2020-01-14 03:09:13 +08:00
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; RUN: -passes='thinlto<O2>' -S %s 2>&1 \
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2020-10-30 12:54:45 +08:00
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; RUN: | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ,%llvmcheckext
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2021-04-06 12:31:07 +08:00
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; RUN: opt -disable-verify -verify-cfg-preserved=0 -debug-pass-manager -passes-ep-pipeline-start='no-op-module' \
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2020-01-14 03:09:13 +08:00
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; RUN: -passes='thinlto<O3>' -S %s 2>&1 \
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2020-10-30 12:54:45 +08:00
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; RUN: | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23SZ,%llvmcheckext
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2021-04-06 12:31:07 +08:00
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; RUN: opt -disable-verify -verify-cfg-preserved=0 -debug-pass-manager \
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2020-01-14 03:09:13 +08:00
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; RUN: -passes='thinlto<Os>' -S %s 2>&1 \
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2020-10-30 12:54:45 +08:00
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; RUN: | FileCheck %s --check-prefixes=CHECK-O,CHECK-Os,CHECK-O23SZ,%llvmcheckext
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2021-04-06 12:31:07 +08:00
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; RUN: opt -disable-verify -verify-cfg-preserved=0 -debug-pass-manager \
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2020-01-14 03:09:13 +08:00
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; RUN: -passes='thinlto<Oz>' -S %s 2>&1 \
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2020-10-30 12:54:45 +08:00
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; RUN: | FileCheck %s --check-prefixes=CHECK-O,CHECK-Oz,CHECK-O23SZ,%llvmcheckext
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2021-04-06 12:31:07 +08:00
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; RUN: opt -disable-verify -verify-cfg-preserved=0 -debug-pass-manager -new-pm-debug-info-for-profiling \
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2020-01-14 03:09:13 +08:00
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; RUN: -passes='thinlto<O2>' -S %s 2>&1 \
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2020-10-30 12:54:45 +08:00
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; RUN: | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ,%llvmcheckext
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; Suppress FileCheck --allow-unused-prefixes=false diagnostics.
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; CHECK-NOEXT: {{^}}
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2021-05-04 07:09:56 +08:00
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; CHECK-O: Running pass: Annotation2Metadata
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2020-01-14 03:09:13 +08:00
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; CHECK-O-NEXT: Running pass: ForceFunctionAttrsPass
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; CHECK-EP-PIPELINE-START-NEXT: Running pass: NoOpModulePass
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; CHECK-O-NEXT: Running pass: PGOIndirectCallPromotion
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; CHECK-O-NEXT: Running analysis: ProfileSummaryAnalysis
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; CHECK-O-NEXT: Running analysis: InnerAnalysisManagerProxy
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; CHECK-O-NEXT: Running analysis: OptimizationRemarkEmitterAnalysis
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; CHECK-O-NEXT: Running pass: InferFunctionAttrsPass
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; CHECK-O-NEXT: Running analysis: TargetLibraryAnalysis
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2021-04-13 02:51:51 +08:00
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; CHECK-O-NEXT: Running pass: LowerExpectIntrinsicPass
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2020-01-14 03:09:13 +08:00
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; CHECK-O-NEXT: Running pass: SimplifyCFGPass
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; CHECK-O-NEXT: Running analysis: TargetIRAnalysis
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; CHECK-O-NEXT: Running analysis: AssumptionAnalysis
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; CHECK-O-NEXT: Running pass: SROA
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; CHECK-O-NEXT: Running analysis: DominatorTreeAnalysis
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; CHECK-O-NEXT: Running pass: EarlyCSEPass
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; CHECK-O-NEXT: Running analysis: TargetLibraryAnalysis
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; CHECK-O3-NEXT: Running pass: CallSiteSplittingPass
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2021-03-24 22:11:32 +08:00
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; CHECK-O2-NEXT: Running pass: OpenMPOptPass
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; CHECK-O3-NEXT: Running pass: OpenMPOptPass
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Restore "[WPD/LowerTypeTests] Delay lowering/removal of type tests until after ICP"
This restores commit 80d0a137a5aba6998fadb764f1e11cb901aae233, and the
follow on fix in 873c0d0786dcf22f4af39f65df824917f70f2170, with a new
fix for test failures after a 2-stage clang bootstrap, and a more robust
fix for the Chromium build failure that an earlier version partially
fixed. See also discussion on D75201.
Reviewers: evgeny777
Subscribers: mehdi_amini, Prazek, hiraditya, steven_wu, dexonsmith, arphaman, davidxl, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D73242
2020-03-18 02:08:35 +08:00
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; CHECK-O-NEXT: Running pass: LowerTypeTestsPass
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2020-01-14 03:09:13 +08:00
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; CHECK-O-NEXT: Running pass: IPSCCPPass
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; CHECK-O-NEXT: Running pass: CalledValuePropagationPass
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; CHECK-O-NEXT: Running pass: GlobalOptPass
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2020-07-29 08:08:24 +08:00
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; CHECK-O-NEXT: Running pass: PromotePass
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2020-01-14 03:09:13 +08:00
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; CHECK-O-NEXT: Running pass: DeadArgumentEliminationPass
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; CHECK-O-NEXT: Running pass: InstCombinePass
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; CHECK-O-NEXT: Running analysis: AAManager
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2021-01-21 08:53:03 +08:00
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; CHECK-O-NEXT: Running analysis: BasicAA
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; CHECK-O-NEXT: Running analysis: ScopedNoAliasAA
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; CHECK-O-NEXT: Running analysis: TypeBasedAA
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2020-01-14 03:09:13 +08:00
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; CHECK-O-NEXT: Running analysis: OuterAnalysisManagerProxy
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; CHECK-O-NEXT: Running analysis: BlockFrequencyAnalysis on foo
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; These next two can appear in any order since they are accessed as parameters
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; on the same call to BlockFrequencyInfo::calculate.
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; CHECK-O-DAG: Running analysis: LoopAnalysis on foo
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2020-04-28 17:31:20 +08:00
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; CHECK-O-DAG: Running analysis: BranchProbabilityAnalysis on foo
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; CHECK-O-NEXT: Running analysis: PostDominatorTreeAnalysis on foo
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2020-01-14 03:09:13 +08:00
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; CHECK-O-NEXT: Running pass: SimplifyCFGPass
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2020-04-29 04:25:15 +08:00
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; CHECK-O-NEXT: Running pass: ModuleInlinerWrapperPass
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; CHECK-O-NEXT: Running analysis: InlineAdvisorAnalysis
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[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 15:40:12 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: RequireAnalysisPass<{{.*}}GlobalsAA
|
|
|
|
; CHECK-O-NEXT: Running analysis: GlobalsAA
|
|
|
|
; CHECK-O-NEXT: Running analysis: CallGraphAnalysis
|
2021-04-27 23:56:11 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: InvalidateAnalysisPass<{{.*}}AAManager
|
|
|
|
; CHECK-O-NEXT: Invalidating analysis: AAManager
|
[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 15:40:12 +08:00
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; CHECK-O-NEXT: Running pass: RequireAnalysisPass<{{.*}}ProfileSummaryAnalysis
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[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 15:40:12 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: LICM
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: LoopRotatePass
|
|
|
|
; CHECK-O-NEXT: Running pass: LICM
|
|
|
|
; CHECK-O-NEXT: Running pass: SimpleLoopUnswitchPass
|
|
|
|
; CHECK-O-NEXT: Running pass: SimplifyCFGPass
|
|
|
|
; CHECK-O-NEXT: Running pass: InstCombinePass
|
|
|
|
; CHECK-O-NEXT: Running pass: LoopSimplifyPass
|
|
|
|
; CHECK-O-NEXT: Running pass: LCSSAPass
|
|
|
|
; CHECK-O-NEXT: Running pass: LoopIdiomRecognizePass
|
[PassManager] Run Induction Variable Simplification pass *after* Recognize loop idioms pass, not before
Currently, `-indvars` runs first, and then immediately after `-loop-idiom` does.
I'm not really sure if `-loop-idiom` requires `-indvars` to run beforehand,
but i'm *very* sure that `-indvars` requires `-loop-idiom` to run afterwards,
as it can be seen in the phase-ordering test.
LoopIdiom runs on two types of loops: countable ones, and uncountable ones.
For uncountable ones, IndVars obviously didn't make any change to them,
since they are uncountable, so for them the order should be irrelevant.
For countable ones, well, they should have been countable before IndVars
for IndVars to make any change to them, and since SCEV is used on them,
it shouldn't matter if IndVars have already canonicalized them.
So i don't really see why we'd want the current ordering.
Should this cause issues, it will give us a reproducer test case
that shows flaws in this logic, and we then could adjust accordingly.
While this is quite likely beneficial in-the-wild already,
it's a required part for the full motivational pattern
behind `left-shift-until-bittest` loop idiom (D91038).
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D91800
2020-11-26 00:17:25 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: IndVarSimplifyPass
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: LoopDeletionPass
|
|
|
|
; CHECK-O-NEXT: Running pass: LoopFullUnrollPass
|
|
|
|
; CHECK-O-NEXT: Running pass: SROA on foo
|
|
|
|
; CHECK-Os-NEXT: Running pass: MergedLoadStoreMotionPass
|
|
|
|
; CHECK-Os-NEXT: Running pass: GVN
|
|
|
|
; CHECK-Os-NEXT: Running analysis: MemoryDependenceAnalysis
|
|
|
|
; CHECK-Os-NEXT: Running analysis: PhiValuesAnalysis
|
|
|
|
; CHECK-Oz-NEXT: Running pass: MergedLoadStoreMotionPass
|
|
|
|
; CHECK-Oz-NEXT: Running pass: GVN
|
|
|
|
; CHECK-Oz-NEXT: Running analysis: MemoryDependenceAnalysis
|
|
|
|
; CHECK-Oz-NEXT: Running analysis: PhiValuesAnalysis
|
|
|
|
; CHECK-O2-NEXT: Running pass: MergedLoadStoreMotionPass
|
|
|
|
; CHECK-O2-NEXT: Running pass: GVN
|
|
|
|
; CHECK-O2-NEXT: Running analysis: MemoryDependenceAnalysis
|
|
|
|
; CHECK-O2-NEXT: Running analysis: PhiValuesAnalysis
|
|
|
|
; CHECK-O3-NEXT: Running pass: MergedLoadStoreMotionPass
|
|
|
|
; CHECK-O3-NEXT: Running pass: GVN
|
|
|
|
; CHECK-O3-NEXT: Running analysis: MemoryDependenceAnalysis
|
|
|
|
; CHECK-O3-NEXT: Running analysis: PhiValuesAnalysis
|
2021-01-10 17:52:01 +08:00
|
|
|
; CHECK-O1-NEXT: Running pass: MemCpyOptPass
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: SCCPPass
|
|
|
|
; CHECK-O-NEXT: Running pass: BDCEPass
|
|
|
|
; CHECK-O-NEXT: Running analysis: DemandedBitsAnalysis
|
|
|
|
; CHECK-O-NEXT: Running pass: InstCombinePass
|
|
|
|
; CHECK-O23SZ-NEXT: Running pass: JumpThreadingPass
|
2020-07-31 01:14:02 +08:00
|
|
|
; CHECK-O23SZ-NEXT: Running analysis: LazyValueAnalysis
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O23SZ-NEXT: Running pass: CorrelatedValuePropagationPass
|
2020-07-31 01:14:02 +08:00
|
|
|
; CHECK-O23SZ-NEXT: Invalidating analysis: LazyValueAnalysis
|
2020-10-21 17:21:50 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: ADCEPass
|
2021-01-10 17:52:01 +08:00
|
|
|
; CHECK-O23SZ-NEXT: Running pass: MemCpyOptPass
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O23SZ-NEXT: Running pass: DSEPass
|
|
|
|
; CHECK-O23SZ-NEXT: Running pass: LoopSimplifyPass
|
|
|
|
; CHECK-O23SZ-NEXT: Running pass: LCSSAPass
|
2020-07-29 08:08:24 +08:00
|
|
|
; CHECK-O23SZ-NEXT: Running pass: LICMPass
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: SimplifyCFGPass
|
|
|
|
; CHECK-O-NEXT: Running pass: InstCombinePass
|
|
|
|
; CHECK-O-NEXT: Running pass: GlobalOptPass
|
|
|
|
; CHECK-O-NEXT: Running pass: GlobalDCEPass
|
|
|
|
; CHECK-O-NEXT: Running pass: EliminateAvailableExternallyPass
|
|
|
|
; CHECK-O-NEXT: Running pass: ReversePostOrderFunctionAttrsPass
|
|
|
|
; CHECK-O-NEXT: Running pass: RequireAnalysisPass<{{.*}}GlobalsAA
|
|
|
|
; CHECK-O-NEXT: Running pass: Float2IntPass
|
|
|
|
; CHECK-O-NEXT: Running pass: LowerConstantIntrinsicsPass
|
|
|
|
; CHECK-EXT: Running pass: {{.*}}::Bye
|
2020-07-29 08:08:24 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: LoopSimplifyPass on foo
|
|
|
|
; CHECK-O-NEXT: Running pass: LCSSAPass on foo
|
|
|
|
; CHECK-O-NEXT: Running pass: LoopRotatePass
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: LoopDistributePass
|
2020-04-07 02:16:48 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: InjectTLIMappings
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: LoopVectorizePass
|
|
|
|
; CHECK-O-NEXT: Running pass: LoopLoadEliminationPass
|
|
|
|
; CHECK-O-NEXT: Running analysis: LoopAccessAnalysis
|
|
|
|
; CHECK-O-NEXT: Running pass: InstCombinePass
|
|
|
|
; CHECK-O-NEXT: Running pass: SimplifyCFGPass
|
|
|
|
; CHECK-O2-NEXT: Running pass: SLPVectorizerPass
|
|
|
|
; CHECK-O3-NEXT: Running pass: SLPVectorizerPass
|
|
|
|
; CHECK-Os-NEXT: Running pass: SLPVectorizerPass
|
2020-05-23 00:13:18 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: VectorCombinePass
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: InstCombinePass
|
|
|
|
; CHECK-O-NEXT: Running pass: LoopUnrollPass
|
|
|
|
; CHECK-O-NEXT: Running pass: WarnMissedTransformationsPass
|
|
|
|
; CHECK-O-NEXT: Running pass: InstCombinePass
|
|
|
|
; CHECK-O-NEXT: Running pass: RequireAnalysisPass<{{.*}}OptimizationRemarkEmitterAnalysis
|
|
|
|
; CHECK-O-NEXT: Running pass: LoopSimplifyPass
|
|
|
|
; CHECK-O-NEXT: Running pass: LCSSAPass
|
2020-07-29 08:08:24 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: LICMPass
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: AlignmentFromAssumptionsPass
|
|
|
|
; CHECK-O-NEXT: Running pass: LoopSinkPass
|
|
|
|
; CHECK-O-NEXT: Running pass: InstSimplifyPass
|
|
|
|
; CHECK-O-NEXT: Running pass: DivRemPairsPass
|
|
|
|
; CHECK-O-NEXT: Running pass: SimplifyCFGPass
|
|
|
|
; CHECK-O-NEXT: Running pass: CGProfilePass
|
|
|
|
; CHECK-O-NEXT: Running pass: GlobalDCEPass
|
|
|
|
; CHECK-O-NEXT: Running pass: ConstantMergePass
|
2020-12-30 05:32:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: RelLookupTableConverterPass
|
|
|
|
; CHECK-O-NEXT: Running analysis: TargetIRAnalysis
|
2020-11-13 17:46:55 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: AnnotationRemarksPass on foo
|
2020-01-14 03:09:13 +08:00
|
|
|
; CHECK-O-NEXT: Running pass: PrintModulePass
|
|
|
|
|
|
|
|
; Make sure we get the IR back out without changes when we print the module.
|
|
|
|
; CHECK-O-LABEL: define void @foo(i32 %n) local_unnamed_addr {
|
|
|
|
; CHECK-O-NEXT: entry:
|
|
|
|
; CHECK-O-NEXT: br label %loop
|
|
|
|
; CHECK-O: loop:
|
|
|
|
; CHECK-O-NEXT: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ]
|
|
|
|
; CHECK-O-NEXT: %iv.next = add i32 %iv, 1
|
|
|
|
; CHECK-O-NEXT: tail call void @bar()
|
|
|
|
; CHECK-O-NEXT: %cmp = icmp eq i32 %iv, %n
|
|
|
|
; CHECK-O-NEXT: br i1 %cmp, label %exit, label %loop
|
|
|
|
; CHECK-O: exit:
|
|
|
|
; CHECK-O-NEXT: ret void
|
|
|
|
; CHECK-O-NEXT: }
|
|
|
|
;
|
|
|
|
; Ignore a bunch of intervening metadata containing profile data.
|
|
|
|
;
|
|
|
|
|
|
|
|
declare void @bar() local_unnamed_addr
|
|
|
|
|
|
|
|
define void @foo(i32 %n) local_unnamed_addr {
|
|
|
|
entry:
|
|
|
|
br label %loop
|
|
|
|
loop:
|
|
|
|
%iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ]
|
|
|
|
%iv.next = add i32 %iv, 1
|
|
|
|
tail call void @bar()
|
|
|
|
%cmp = icmp eq i32 %iv, %n
|
|
|
|
br i1 %cmp, label %exit, label %loop
|
|
|
|
exit:
|
|
|
|
ret void
|
|
|
|
}
|
|
|
|
|
|
|
|
!llvm.module.flags = !{!0}
|
|
|
|
|
|
|
|
!0 = !{i32 1, !"ProfileSummary", !1}
|
|
|
|
!1 = !{!2, !3, !4, !5, !6, !7, !8, !9}
|
|
|
|
!2 = !{!"ProfileFormat", !"InstrProf"}
|
|
|
|
!3 = !{!"TotalCount", i64 0}
|
|
|
|
!4 = !{!"MaxCount", i64 0}
|
|
|
|
!5 = !{!"MaxInternalCount", i64 0}
|
|
|
|
!6 = !{!"MaxFunctionCount", i64 0}
|
|
|
|
!7 = !{!"NumCounts", i64 0}
|
|
|
|
!8 = !{!"NumFunctions", i64 0}
|
|
|
|
!9 = !{!"DetailedSummary", !10}
|
|
|
|
!10 = !{!11, !12, !13, !14, !15, !16, !17, !18, !19, !20, !21, !22, !23, !24, !25, !26}
|
|
|
|
!11 = !{i32 10000, i64 0, i32 0}
|
|
|
|
!12 = !{i32 100000, i64 0, i32 0}
|
|
|
|
!13 = !{i32 200000, i64 0, i32 0}
|
|
|
|
!14 = !{i32 300000, i64 0, i32 0}
|
|
|
|
!15 = !{i32 400000, i64 0, i32 0}
|
|
|
|
!16 = !{i32 500000, i64 0, i32 0}
|
|
|
|
!17 = !{i32 600000, i64 0, i32 0}
|
|
|
|
!18 = !{i32 700000, i64 0, i32 0}
|
|
|
|
!19 = !{i32 800000, i64 0, i32 0}
|
|
|
|
!20 = !{i32 900000, i64 0, i32 0}
|
|
|
|
!21 = !{i32 950000, i64 0, i32 0}
|
|
|
|
!22 = !{i32 990000, i64 0, i32 0}
|
|
|
|
!23 = !{i32 999000, i64 0, i32 0}
|
|
|
|
!24 = !{i32 999900, i64 0, i32 0}
|
|
|
|
!25 = !{i32 999990, i64 0, i32 0}
|
|
|
|
!26 = !{i32 999999, i64 0, i32 0}
|