2020-08-18 02:48:04 +02:00
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; RUN: opt -enable-new-pm=0 -mtriple=x86_64-- -O3 -debug-pass=Structure < %s -o /dev/null 2>&1 | FileCheck --check-prefixes=CHECK,%llvmcheckext %s
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2018-03-21 23:17:31 +01:00
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; REQUIRES: asserts
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; CHECK-LABEL: Pass Arguments:
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; CHECK-NEXT: Target Transform Information
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; CHECK-NEXT: Type-Based Alias Analysis
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; CHECK-NEXT: Scoped NoAlias Alias Analysis
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; CHECK-NEXT: Assumption Cache Tracker
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; CHECK-NEXT: Target Library Information
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; CHECK-NEXT: FunctionPass Manager
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; CHECK-NEXT: Module Verifier
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2019-06-08 17:37:47 +02:00
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; CHECK-EXT: Good Bye World Pass
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; CHECK-NOEXT-NOT: Good Bye World Pass
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2021-04-12 20:51:51 +02:00
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; CHECK-NEXT: Lower 'expect' Intrinsics
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Simplify the CFG
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; CHECK-NEXT: Dominator Tree Construction
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; CHECK-NEXT: SROA
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; CHECK-NEXT: Early CSE
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; CHECK-NEXT: Pass Arguments:
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; CHECK-NEXT: Target Library Information
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; CHECK-NEXT: Target Transform Information
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2018-03-21 23:57:33 +01:00
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; Target Pass Configuration
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; CHECK: Type-Based Alias Analysis
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Scoped NoAlias Alias Analysis
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; CHECK-NEXT: Assumption Cache Tracker
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; CHECK-NEXT: Profile summary info
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; CHECK-NEXT: ModulePass Manager
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2020-11-16 10:49:04 +01:00
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; CHECK-NEXT: Annotation2Metadata
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Force set function attributes
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; CHECK-NEXT: Infer set function attributes
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; CHECK-NEXT: FunctionPass Manager
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2018-11-14 11:04:30 +01:00
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; CHECK-NEXT: Dominator Tree Construction
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Call-site splitting
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; CHECK-NEXT: Interprocedural Sparse Conditional Constant Propagation
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2019-11-01 12:43:51 +01:00
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; CHECK-NEXT: FunctionPass Manager
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; CHECK-NEXT: Dominator Tree Construction
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Called Value Propagation
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; CHECK-NEXT: Global Variable Optimizer
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2019-11-01 12:43:51 +01:00
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; CHECK-NEXT: FunctionPass Manager
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; CHECK-NEXT: Dominator Tree Construction
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; CHECK-NEXT: Natural Loop Information
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2020-04-28 11:31:20 +02:00
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; CHECK-NEXT: Post-Dominator Tree Construction
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2019-11-01 12:43:51 +01:00
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; CHECK-NEXT: Branch Probability Analysis
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; CHECK-NEXT: Block Frequency Analysis
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: FunctionPass Manager
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; CHECK-NEXT: Dominator Tree Construction
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; CHECK-NEXT: Promote Memory to Register
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; CHECK-NEXT: Dead Argument Elimination
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; CHECK-NEXT: FunctionPass Manager
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; CHECK-NEXT: Dominator Tree Construction
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; CHECK-NEXT: Basic Alias Analysis (stateless AA impl)
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; CHECK-NEXT: Function Alias Analysis Results
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; CHECK-NEXT: Natural Loop Information
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; CHECK-NEXT: Lazy Branch Probability Analysis
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; CHECK-NEXT: Lazy Block Frequency Analysis
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; CHECK-NEXT: Optimization Remark Emitter
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; CHECK-NEXT: Combine redundant instructions
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; CHECK-NEXT: Simplify the CFG
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; CHECK-NEXT: CallGraph Construction
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; CHECK-NEXT: Globals Alias Analysis
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; CHECK-NEXT: Call Graph SCC Pass Manager
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; CHECK-NEXT: Remove unused exception handling info
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; CHECK-NEXT: Function Integration/Inlining
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2019-11-07 06:20:06 +01:00
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; CHECK-NEXT: OpenMP specific optimizations
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Deduce function attributes
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; CHECK-NEXT: Promote 'by reference' arguments to scalars
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; CHECK-NEXT: FunctionPass Manager
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; CHECK-NEXT: Dominator Tree Construction
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; CHECK-NEXT: SROA
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; CHECK-NEXT: Basic Alias Analysis (stateless AA impl)
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; CHECK-NEXT: Function Alias Analysis Results
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; CHECK-NEXT: Memory SSA
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; CHECK-NEXT: Early CSE w/ MemorySSA
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; CHECK-NEXT: Speculatively execute instructions if target has divergent branches
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; CHECK-NEXT: Function Alias Analysis Results
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; CHECK-NEXT: Lazy Value Information Analysis
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; CHECK-NEXT: Jump Threading
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; CHECK-NEXT: Value Propagation
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; CHECK-NEXT: Simplify the CFG
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; CHECK-NEXT: Dominator Tree Construction
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; CHECK-NEXT: Combine pattern based expressions
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; CHECK-NEXT: Basic Alias Analysis (stateless AA impl)
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; CHECK-NEXT: Function Alias Analysis Results
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; CHECK-NEXT: Natural Loop Information
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; CHECK-NEXT: Lazy Branch Probability Analysis
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; CHECK-NEXT: Lazy Block Frequency Analysis
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; CHECK-NEXT: Optimization Remark Emitter
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; CHECK-NEXT: Combine redundant instructions
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; CHECK-NEXT: Conditionally eliminate dead library calls
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; CHECK-NEXT: Natural Loop Information
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2020-04-28 11:31:20 +02:00
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; CHECK-NEXT: Post-Dominator Tree Construction
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Branch Probability Analysis
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; CHECK-NEXT: Block Frequency Analysis
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; CHECK-NEXT: Lazy Branch Probability Analysis
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; CHECK-NEXT: Lazy Block Frequency Analysis
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; CHECK-NEXT: Optimization Remark Emitter
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; CHECK-NEXT: PGOMemOPSize
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; CHECK-NEXT: Basic Alias Analysis (stateless AA impl)
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; CHECK-NEXT: Function Alias Analysis Results
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; CHECK-NEXT: Natural Loop Information
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; CHECK-NEXT: Lazy Branch Probability Analysis
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; CHECK-NEXT: Lazy Block Frequency Analysis
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; CHECK-NEXT: Optimization Remark Emitter
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; CHECK-NEXT: Tail Call Elimination
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; CHECK-NEXT: Simplify the CFG
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; CHECK-NEXT: Reassociate expressions
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; CHECK-NEXT: Dominator Tree Construction
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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 09:40:12 +02:00
|
|
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; CHECK-NEXT: Basic Alias Analysis (stateless AA impl)
|
|
|
|
; CHECK-NEXT: Function Alias Analysis Results
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|
|
|
; CHECK-NEXT: Memory SSA
|
2018-03-21 23:17:31 +01:00
|
|
|
; CHECK-NEXT: Natural Loop Information
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; CHECK-NEXT: Canonicalize natural loops
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; CHECK-NEXT: LCSSA Verifier
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; CHECK-NEXT: Loop-Closed SSA Form Pass
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; CHECK-NEXT: Scalar Evolution Analysis
|
[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 09:40:12 +02:00
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; CHECK-NEXT: Lazy Branch Probability Analysis
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; CHECK-NEXT: Loop Invariant Code Motion
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Rotate Loops
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; CHECK-NEXT: Loop Invariant Code Motion
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[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
2020-11-25 17:17:25 +01:00
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2018-03-21 23:17:31 +01:00
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2020-10-04 10:27:07 +02:00
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: MergedLoadStoreMotion
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2018-07-31 16:19:29 +02:00
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2018-03-21 23:17:31 +01:00
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2021-01-10 10:52:01 +01:00
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2018-03-21 23:17:31 +01:00
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2020-10-21 11:21:50 +02:00
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2018-03-21 23:17:31 +01:00
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2020-09-26 18:56:15 +02:00
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; CHECK-NEXT: Memory SSA
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2021-01-10 10:52:01 +01:00
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; CHECK-NEXT: MemCpy Optimization
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2018-03-21 23:17:31 +01:00
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2021-05-31 11:22:37 +02:00
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; CHECK-NEXT: Dead Store Elimination
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: LCSSA Verifier
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2020-10-16 09:42:18 +02:00
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Scalar Evolution Analysis
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2020-09-16 01:09:30 +02:00
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; CHECK-NEXT: Lazy Branch Probability Analysis
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2018-03-21 23:17:31 +01:00
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2019-11-01 12:43:51 +01:00
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2020-04-28 11:31:20 +02:00
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2019-11-01 12:43:51 +01:00
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2018-03-21 23:17:31 +01:00
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2019-09-19 18:31:17 +02:00
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2019-10-14 18:15:14 +02:00
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2020-02-13 19:49:44 +01:00
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2018-03-21 23:17:31 +01:00
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2020-04-28 11:31:20 +02:00
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Branch Probability Analysis
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2019-12-13 20:43:26 +01:00
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; CHECK-NEXT: Inject TLI Mappings
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Loop Vectorization
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; CHECK-NEXT: Canonicalize natural loops
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2019-04-15 18:49:00 +02:00
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; CHECK-NEXT: Lazy Branch Probability Analysis
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2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Loop Load Elimination
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; CHECK-NEXT: Basic Alias Analysis (stateless AA impl)
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; CHECK-NEXT: Dominator Tree Construction
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; CHECK-NEXT: Natural Loop Information
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; CHECK-NEXT: Scalar Evolution Analysis
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; CHECK-NEXT: Basic Alias Analysis (stateless AA impl)
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; CHECK-NEXT: Function Alias Analysis Results
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; CHECK-NEXT: Demanded bits analysis
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; CHECK-NEXT: Lazy Branch Probability Analysis
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; CHECK-NEXT: Lazy Block Frequency Analysis
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; CHECK-NEXT: Optimization Remark Emitter
|
2020-03-10 14:03:43 +01:00
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; CHECK-NEXT: Inject TLI Mappings
|
2018-03-21 23:17:31 +01:00
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|
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; CHECK-NEXT: SLP Vectorizer
|
2020-05-22 18:13:18 +02:00
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; CHECK-NEXT: Optimize scalar/vector ops
|
2018-03-21 23:17:31 +01:00
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; CHECK-NEXT: Optimization Remark Emitter
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|
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|
; CHECK-NEXT: Combine redundant instructions
|
|
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|
; CHECK-NEXT: Canonicalize natural loops
|
|
|
|
; CHECK-NEXT: LCSSA Verifier
|
|
|
|
; CHECK-NEXT: Loop-Closed SSA Form Pass
|
|
|
|
; CHECK-NEXT: Scalar Evolution Analysis
|
|
|
|
; CHECK-NEXT: Loop Pass Manager
|
|
|
|
; CHECK-NEXT: Unroll loops
|
|
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; CHECK-NEXT: Lazy Branch Probability Analysis
|
|
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|
; CHECK-NEXT: Lazy Block Frequency Analysis
|
|
|
|
; CHECK-NEXT: Optimization Remark Emitter
|
|
|
|
; CHECK-NEXT: Combine redundant instructions
|
2019-09-04 21:16:04 +02:00
|
|
|
; CHECK-NEXT: Memory SSA
|
2018-03-21 23:17:31 +01:00
|
|
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; CHECK-NEXT: Canonicalize natural loops
|
|
|
|
; CHECK-NEXT: LCSSA Verifier
|
|
|
|
; CHECK-NEXT: Loop-Closed SSA Form Pass
|
|
|
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; CHECK-NEXT: Scalar Evolution Analysis
|
[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 = !{!0, !1, !2}
!1 = !{!"llvm.loop.unroll_and_jam.enable"}
!2 = !{!"llvm.loop.unroll_and_jam.followup_inner", !3}
!3 = !{!"llvm.loop.distribute.enable"}
defines a loop ID (!0) to be unrolled-and-jammed (!1) and then the attribute !3 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 18:32:52 +01:00
|
|
|
; CHECK-NEXT: Lazy Branch Probability Analysis
|
|
|
|
; CHECK-NEXT: Lazy Block Frequency Analysis
|
2020-09-16 01:09:30 +02:00
|
|
|
; CHECK-NEXT: Loop Pass Manager
|
|
|
|
; CHECK-NEXT: Loop Invariant Code Motion
|
[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 = !{!0, !1, !2}
!1 = !{!"llvm.loop.unroll_and_jam.enable"}
!2 = !{!"llvm.loop.unroll_and_jam.followup_inner", !3}
!3 = !{!"llvm.loop.distribute.enable"}
defines a loop ID (!0) to be unrolled-and-jammed (!1) and then the attribute !3 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 18:32:52 +01:00
|
|
|
; CHECK-NEXT: Optimization Remark Emitter
|
|
|
|
; CHECK-NEXT: Warn about non-applied transformations
|
2018-03-21 23:17:31 +01:00
|
|
|
; CHECK-NEXT: Alignment from assumptions
|
|
|
|
; CHECK-NEXT: Strip Unused Function Prototypes
|
|
|
|
; CHECK-NEXT: Dead Global Elimination
|
|
|
|
; CHECK-NEXT: Merge Duplicate Global Constants
|
[LPM] Port CGProfilePass from NPM to LPM
Reviewers: hans, chandlerc!, asbirlea, nikic
Reviewed By: hans, nikic
Subscribers: steven_wu, dexonsmith, nikic, echristo, void, zhizhouy, cfe-commits, aeubanks, MaskRay, jvesely, nhaehnle, hiraditya, kerbowa, llvm-commits
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D83013
2020-07-08 21:30:28 +02:00
|
|
|
; CHECK-NEXT: Call Graph Profile
|
|
|
|
; CHECK-NEXT: FunctionPass Manager
|
|
|
|
; CHECK-NEXT: Dominator Tree Construction
|
|
|
|
; CHECK-NEXT: Natural Loop Information
|
|
|
|
; CHECK-NEXT: Lazy Branch Probability Analysis
|
|
|
|
; CHECK-NEXT: Lazy Block Frequency Analysis
|
2018-03-21 23:17:31 +01:00
|
|
|
; CHECK-NEXT: FunctionPass Manager
|
|
|
|
; CHECK-NEXT: Dominator Tree Construction
|
|
|
|
; CHECK-NEXT: Natural Loop Information
|
2020-04-28 11:31:20 +02:00
|
|
|
; CHECK-NEXT: Post-Dominator Tree Construction
|
2018-03-21 23:17:31 +01:00
|
|
|
; CHECK-NEXT: Branch Probability Analysis
|
|
|
|
; CHECK-NEXT: Block Frequency Analysis
|
|
|
|
; CHECK-NEXT: Canonicalize natural loops
|
|
|
|
; CHECK-NEXT: LCSSA Verifier
|
|
|
|
; CHECK-NEXT: Loop-Closed SSA Form Pass
|
|
|
|
; CHECK-NEXT: Basic Alias Analysis (stateless AA impl)
|
|
|
|
; CHECK-NEXT: Function Alias Analysis Results
|
|
|
|
; CHECK-NEXT: Scalar Evolution Analysis
|
|
|
|
; CHECK-NEXT: Block Frequency Analysis
|
|
|
|
; CHECK-NEXT: Loop Pass Manager
|
|
|
|
; CHECK-NEXT: Loop Sink
|
|
|
|
; CHECK-NEXT: Lazy Branch Probability Analysis
|
|
|
|
; CHECK-NEXT: Lazy Block Frequency Analysis
|
|
|
|
; CHECK-NEXT: Optimization Remark Emitter
|
|
|
|
; CHECK-NEXT: Remove redundant instructions
|
|
|
|
; CHECK-NEXT: Hoist/decompose integer division and remainder
|
|
|
|
; CHECK-NEXT: Simplify the CFG
|
2020-11-13 10:46:55 +01:00
|
|
|
; CHECK-NEXT: Annotation Remarks
|
2018-03-21 23:17:31 +01:00
|
|
|
; CHECK-NEXT: Module Verifier
|
|
|
|
; CHECK-NEXT: Bitcode Writer
|
|
|
|
; CHECK-NEXT: Pass Arguments:
|
2018-08-23 13:04:00 +02:00
|
|
|
; CHECK-NEXT: FunctionPass Manager
|
|
|
|
; CHECK-NEXT: Dominator Tree Construction
|
|
|
|
; CHECK-NEXT: Pass Arguments:
|
2018-03-21 23:17:31 +01:00
|
|
|
; CHECK-NEXT: Target Library Information
|
|
|
|
; CHECK-NEXT: FunctionPass Manager
|
|
|
|
; CHECK-NEXT: Dominator Tree Construction
|
|
|
|
; CHECK-NEXT: Natural Loop Information
|
2020-04-28 11:31:20 +02:00
|
|
|
; CHECK-NEXT: Post-Dominator Tree Construction
|
2018-03-21 23:17:31 +01:00
|
|
|
; CHECK-NEXT: Branch Probability Analysis
|
|
|
|
; CHECK-NEXT: Block Frequency Analysis
|
|
|
|
; CHECK-NEXT: Pass Arguments:
|
|
|
|
; CHECK-NEXT: Target Library Information
|
|
|
|
; CHECK-NEXT: FunctionPass Manager
|
|
|
|
; CHECK-NEXT: Dominator Tree Construction
|
|
|
|
; CHECK-NEXT: Natural Loop Information
|
2020-04-28 11:31:20 +02:00
|
|
|
; CHECK-NEXT: Post-Dominator Tree Construction
|
2018-03-21 23:17:31 +01:00
|
|
|
; CHECK-NEXT: Branch Probability Analysis
|
|
|
|
; CHECK-NEXT: Block Frequency Analysis
|
|
|
|
|
|
|
|
define void @f() {
|
|
|
|
ret void
|
|
|
|
}
|