Florian Hahn fbcf8a8cbb [ConstraintElim] Add (UGE, var, 0) to unsigned system for new vars. (#76262) ...

The constraint system used for ConstraintElimination assumes all
varibles to be signed. This can cause missed optimization in the
unsigned system, due to missing the information that all variables are
unsigned (non-negative).

Variables can be marked as non-negative by adding Var >= 0 for all
variables. This is done for arguments on ConstraintInfo construction and
after adding new variables. This handles cases like the ones outlined in
https://discourse.llvm.org/t/why-does-llvm-not-perform-range-analysis-on-integer-values/74341

The original example shared above is now handled without this change,
but adding another variable means that instcombine won't be able to
simplify examples like https://godbolt.org/z/hTnra7zdY

Adding the extra variables comes with a slight compile-time increase
https://llvm-compile-time-tracker.com/compare.php?from=7568b36a2bc1a1e496ec29246966ffdfc3a8b87f&to=641a47f0acce7755e340447386013a2e086f03d9&stat=instructions:u

stage1-O3    stage1-ReleaseThinLTO    stage1-ReleaseLTO-g  stage1-O0-g
 +0.04%           +0.07%                   +0.05%           +0.02%
stage2-O3    stage2-O0-g    stage2-clang
  +0.05%         +0.05%        +0.05%

https://github.com/llvm/llvm-project/pull/76262

2023-12-23 15:53:48 +01:00

..

AArch64

[InstCombine] Set disjoint flag when turning Add into Or. (#72702)

2023-11-27 12:54:11 -08:00

ARM

Revert "[PM] Execute IndVarSimplifyPass precede RessociatePass" (#71617)

2023-11-08 09:22:55 +08:00

SystemZ

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X86

[InstCombine] Replace non-demanded undef vector with poison

2023-12-18 16:12:37 +01:00

2010-03-22-empty-baseclass.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

assume-explosion.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

basic.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

bitcast-store-branch.ll

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bitfield-bittests.ll

Revert "Temporarily Revert "Add basic loop fusion pass.""

2019-04-17 04:52:47 +00:00

cmp-logic.ll

[CVP] When expanding urem, always freeze the nominator

2022-12-31 05:00:43 +03:00

d83507-knowledge-retention-bug.ll

[NFC] Port all PhaseOrdering tests to -passes= syntax

2022-12-08 02:38:50 +03:00

dae-dce.ll

[Pipelines] Restore old DAE position in LTO pipeline

2023-03-14 17:00:17 +01:00

dce-after-argument-promotion-loads.ll

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dce-after-argument-promotion.ll

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deletion-of-loops-that-became-side-effect-free.ll

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dse-ephemeral-value-captures.ll

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early-arg-attrs-inference.ll

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expect.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

fast-basictest.ll

[NFC] Port all PhaseOrdering tests to -passes= syntax

2022-12-08 02:38:50 +03:00

fast-reassociate-gvn.ll

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func-attrs.ll

[Pipeline] Adjust PostOrderFunctionAttrs placement in simplification pipeline

2023-03-06 09:01:45 -08:00

gdce.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

gep-null-compare-in-loop.ll

[InstCombine] Preserve inbounds when folding select of GEP

2023-07-07 09:56:33 +02:00

globalaa-retained.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

gvn-replacement-vs-hoist.ll

[InstCombine] Infer nneg on zext when forming from non-negative sext (#70706)

2023-10-30 12:09:43 -07:00

icmp-ashr-breaking-select-idiom.ll

Revert "Revert "[InstCombine] Add oneuse checks to shr + cmp constant folds.""

2023-10-28 03:12:15 -07:00

inlining-alignment-assumptions.ll

[InferAlignment] Enable InferAlignment pass by default

2023-09-20 12:08:52 +05:30

instcombine-sroa-inttoptr.ll

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lifetime-sanitizer.ll

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loop-access-checks.ll

[ConstraintElim] Use isKnownNonNegative for condition transfer. (#72879)

2023-11-21 10:09:35 +00:00

loop-rotation-vs-common-code-hoisting.ll

[ValueTracking] Add dominating condition support in computeKnownBits() (#73662)

2023-12-06 14:17:18 +01:00

lower-table-based-cttz.ll

Recommit "[AggressiveInstCombine] Lower Table Based CTTZ

2022-09-20 13:12:47 +02:00

lto-licm.ll

[InstCombine] Infer nneg on zext when forming from non-negative sext (#70706)

2023-10-30 12:09:43 -07:00

memset-tail.ll

Revert "[FunctionAttrs] Propagate some func/arg/ret attributes from caller to callsite (WIP)"

2023-06-13 00:53:31 -05:00

min_max_loop.ll

[InstCombine] Use zext's nneg flag for icmp folding (#70845)

2023-11-13 00:53:53 +08:00

min-max-abs-cse.ll

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minmax.ll

[Passes] add a tail-call-elim pass near the end of the opt pipeline

2022-07-25 15:25:47 -04:00

openmp-opt-module.ll

[OpenMP][NFC] Split the reduction buffer size into two components

2023-11-06 11:50:41 -08:00

partialord-ule.ll

[SimplifyCFG] Handle two equal cases in switch to select

2021-04-04 17:27:28 +02:00

pr32544.ll

Revert "[SCCP] Support NUW/NSW inference for all overflowing binary operators."

2023-01-28 21:33:28 +00:00

pr36760.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

pr39116.ll

[NFC] Port all PhaseOrdering tests to -passes= syntax

2022-12-08 02:38:50 +03:00

pr39282.ll

[PhaseOrdering] Regenerate test checks (NFC)

2023-10-12 14:40:13 +02:00

pr40750.ll

[NFC] Port all PhaseOrdering tests to -passes= syntax

2022-12-08 02:38:50 +03:00

pr44461-br-to-switch-rotate.ll

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pr45682.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

pr45687.ll

[PhaseOrdering] Remove RUN lines for legacy PM (NFC)

2022-04-21 14:43:00 +02:00

pr62311.ll

[InstCombine] (icmp eq A, -1) & (icmp eq B, -1) --> (icmp eq (A&B), -1)

2023-06-08 09:00:05 +05:30

pr64289-tce.ll

[TailCallElim] Remove the readonly attribute of byval.

2023-08-09 07:07:47 +08:00

PR6627.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

reassociate-after-unroll.ll

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reassociate-gvn-bdce.ll

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reassociate-instcombine.ll

[InstCombine] fold udiv with common shl amount in operands

2022-10-12 11:12:26 -04:00

recompute-globalsaa.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

rotate.ll

[PhaseOrdering] Remove unused check-prefixes

2020-11-08 13:30:18 +00:00

runtime-check-removal.ll

[ConstraintElim] Add (UGE, var, 0) to unsigned system for new vars. (#76262)

2023-12-23 15:53:48 +01:00

scev-custom-dl.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

scev.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

simplifycfg-options.ll

[InstCombine] Try to fold not into cmp iff other users of cmp are freely invertible

2022-12-19 00:24:28 +03:00

simplifycfg-switch-lowering-vs-correlatedpropagation.ll

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single-iteration-loop-sroa.ll

[InstCombine] Revert D125845

2022-11-29 22:02:40 +00:00

srem.ll

[SCCP] convert signed div/rem to unsigned for non-negative operands, 2nd try

2022-09-07 11:56:29 -04:00

swap-promotion.ll

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switch_with_geps.ll

[PhaseOrdering] Add data layout to test (NFC)

2023-12-20 11:49:34 +01:00

two-shifts-by-sext.ll

[InstCombine] Add exact flags for ext idiom shr (shl X, Y), Y (#72483)

2023-11-16 17:30:01 +08:00

vector-select.ll

PhaseOrdering: Convert tests to opaque pointers

2022-11-27 21:26:41 -05:00

vector-trunc-inseltpoison.ll

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vector-trunc.ll

[PhaseOrdering] Remove unused check-prefixes

2020-11-08 13:30:18 +00:00