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llvm-project/llvm/test/Analysis/ScalarEvolution
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Alexandre Isoard 405728fd47 [SCEV] Add URem support to SCEV 
In LLVM IR the following code:

    %r = urem <ty> %t, %b

is equivalent to

    %q = udiv <ty> %t, %b
    %s = mul <ty> nuw %q, %b
    %r = sub <ty> nuw %t, %q ; (t / b) * b + (t % b) = t

As UDiv, Mul and Sub are already supported by SCEV, URem can be implemented
with minimal effort using that relation:

    %r --> (-%b * (%t /u %b)) + %t

We implement two special cases:

  - if %b is 1, the result is always 0
  - if %b is a power-of-two, we produce a zext/trunc based expression instead

That is, the following code:

    %r = urem i32 %t, 65536

Produces:

    %r --> (zext i16 (trunc i32 %a to i16) to i32)

Note that while this helps get a tighter bound on the range analysis and the
known-bits analysis, this exposes some normalization shortcoming of SCEVs:

    %div = udim i32 %a, 65536
    %mul = mul i32 %div, 65536
    %rem = urem i32 %a, 65536
    %add = add i32 %mul, %rem

Will usually not be reduced.

llvm-svn: 312329
 		2017-09-01 14:59:59 +00:00
..
2007-07-15-NegativeStride.ll [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction 2015-02-27 19:29:02 +00:00
2007-08-06-MisinterpretBranch.ll
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2007-08-06-Unsigned.ll
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2007-09-27-LargeStepping.ll
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2007-11-14-SignedAddRec.ll
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2007-11-18-OrInstruction.ll
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2008-02-11-ReversedCondition.ll
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2008-02-12-SMAXTripCount.ll
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2008-02-15-UMax.ll
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2008-05-25-NegativeStepToZero.ll
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2008-06-12-BinomialInt64.ll
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2008-07-12-UnneededSelect1.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
2008-07-12-UnneededSelect2.ll
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2008-07-19-InfiniteLoop.ll
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2008-07-19-WrappingIV.ll
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2008-07-29-SGTTripCount.ll
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2008-07-29-SMinExpr.ll
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2008-08-04-IVOverflow.ll
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2008-08-04-LongAddRec.ll
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2008-11-02-QuadraticCrash.ll
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2008-11-15-CubicOOM.ll
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2008-11-18-LessThanOrEqual.ll [opaque pointer type] Add textual IR support for explicit type parameter to the call instruction 2015-04-16 23:24:18 +00:00
2008-11-18-Stride1.ll
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2008-11-18-Stride2.ll
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2008-12-08-FiniteSGE.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
2008-12-11-SMaxOverflow.ll
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2008-12-14-StrideAndSigned.ll
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2008-12-15-DontUseSDiv.ll
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2009-01-02-SignedNegativeStride.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
2009-04-22-TruncCast.ll
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2009-05-09-PointerEdgeCount.ll [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction 2015-02-27 19:29:02 +00:00
2009-07-04-GroupConstantsWidthMismatch.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
2010-09-03-RequiredTransitive.ll
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2011-03-09-ExactNoMaxBECount.ll
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2011-04-26-FoldAddRec.ll [PM] Clean up the testing for IVUsers, especially with the new PM. 2017-01-15 09:29:27 +00:00
2011-10-04-ConstEvolve.ll
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2012-03-26-LoadConstant.ll [opaque pointer type] Add textual IR support for explicit type parameter to the call instruction 2015-04-16 23:24:18 +00:00
2012-05-18-LoopPredRecurse.ll [PM] Clean up the testing for IVUsers, especially with the new PM. 2017-01-15 09:29:27 +00:00
2012-05-29-MulAddRec.ll
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SolveQuadraticEquation.ll [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction 2015-02-27 19:29:02 +00:00
ZeroStep.ll [SCEV] createAddRecFromPHI: Optimize for the most common case. 2017-05-03 23:53:38 +00:00
and-xor.ll
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avoid-assume-hang.ll ScalarEvolution assume hanging bugfix 2015-09-09 20:47:30 +00:00
avoid-infinite-recursion-0.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
avoid-infinite-recursion-1.ll [PM] Clean up the testing for IVUsers, especially with the new PM. 2017-01-15 09:29:27 +00:00
avoid-smax-0.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
avoid-smax-1.ll Revert "Change memcpy/memset/memmove to have dest and source alignments." 2015-11-19 05:56:52 +00:00
cache_loop_exit_limit.ll [SCEV] Re-enable "Cache results of computeExitLimit" 2017-08-03 08:41:30 +00:00
constant_condition.ll Revert "Revert "This patch builds on top of D13378 to handle constant condition."" 2015-10-07 18:14:25 +00:00
different-loops-recs.ll Re-enable "[SCEV] Do not fold dominated SCEVUnknown into AddRecExpr start" 2017-05-26 06:47:04 +00:00
div-overflow.ll
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do-loop.ll
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exhaustive-trip-counts.ll [SCEV] Compute max be count from shift operator only if all else fails 2016-06-30 02:47:28 +00:00
expander-replace-congruent-ivs.ll [SCEVExpander] Fix a failed cast<> assertion 2016-05-11 17:41:41 +00:00
exponential-behavior.ll [SCEV] Fix exponential time complexity by caching 2017-04-24 00:09:46 +00:00
ext-antecedent.ll [SCEV] Revert bailout added in r75511. 2015-03-26 17:28:26 +00:00
flags-from-poison-dbg.ll Teach isGuarantdToTransferExecToSuccessor about debug info intrinsics 2016-06-08 17:48:36 +00:00
flags-from-poison.ll [SCEV] Preserve NSW information for sext(subtract). 2017-08-04 20:19:46 +00:00
flattened-0.ll [SCEV] Add URem support to SCEV 2017-09-01 14:59:59 +00:00
fold.ll When simplifying a SCEV truncate by distributing, consider it a simplification to replace a cast, even if we end up with a trunc around the term. Fixes PR22960! 2015-03-20 02:25:00 +00:00
guards.ll Re-enable "[IndVars] Canonicalize comparisons between non-negative values and indvars" 2017-07-08 17:17:30 +00:00
how-far-to-zero.ll
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implied-via-addition.ll [ScalarEvolution] Re-enable Predicate implication from operations 2017-03-31 12:05:30 +00:00
implied-via-division.ll [ScalarEvolution] Re-enable Predicate implication from operations 2017-03-31 12:05:30 +00:00
incorrect-nsw.ll
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increasing-or-decreasing-iv.ll Remove trailing newline from test case; NFC 2016-03-09 01:51:44 +00:00
infer-prestart-no-wrap.ll [SCEV] Don't always add no-wrap flags to post-inc add recs 2016-05-29 00:32:17 +00:00
infer-via-ranges.ll [SCEV] Make isImpliedCond smarter. 2015-03-18 00:41:29 +00:00
invalidation.ll [PM] The assumption cache is fundamentally designed to be self-updating, 2017-01-15 00:26:18 +00:00
latch-dominating-conditions.ll [SCEV] Look at backedge dominating conditions (re-land r233447). 2015-04-01 18:24:06 +00:00
limit-depth.ll [SCEV] Use depth limit instead of local cache for SExt and ZExt 2017-06-30 05:04:09 +00:00
load-with-range-metadata.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
load.ll [SCEV] Add a `scalar-evolution-print-constant-ranges' option 2015-03-09 21:43:39 +00:00
max-addops-inline.ll [SCEV] Introduce add operation inlining limit 2017-01-26 13:33:17 +00:00
max-addrec-size.ll [SCEV] Limit max size of AddRecExpr during evolving 2017-07-23 15:40:19 +00:00
max-mulops-inline.ll [SCEV] Add a threshold to restrict number of mul operands to be inlined into SCEV 2016-10-20 21:38:39 +00:00
max-trip-count-address-space.ll [SCEV] Add a `scalar-evolution-print-constant-ranges' option 2015-03-09 21:43:39 +00:00
max-trip-count.ll [SCEV] Make howFarToZero max backedge-taken count check for precondition. 2017-01-11 21:07:15 +00:00
min-max-exprs.ll [SCEV] Mark AddExprs as nsw or nuw if legal 2015-10-22 19:57:19 +00:00
no-wrap-add-exprs.ll [SCEV] Commute zero extends through <nuw> additions 2015-10-22 19:57:38 +00:00
no-wrap-unknown-becount.ll Revert @llvm.assume with operator bundles (r289755-r289757) 2016-12-19 08:22:17 +00:00
non-IV-phi.ll [SCEV] Generalize the SCEV algorithm for creating expressions for PHI nodes 2015-10-30 15:02:28 +00:00
nowrap-preinc-limits.ll [SCEV] Don't always add no-wrap flags to post-inc add recs 2016-05-29 00:32:17 +00:00
nsw-offset-assume.ll Revert @llvm.assume with operator bundles (r289755-r289757) 2016-12-19 08:22:17 +00:00
nsw-offset.ll [SCEV] No-wrap flags are not propagated when folding "{S,+,X}+T ==> {S+T,+,X}" 2016-05-25 13:01:33 +00:00
nsw.ll [SCEV] Clarify behavior around max backedge taken count 2017-05-22 06:46:04 +00:00
nw-sub-is-not-nw-add.ll
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overflow-intrinsics.ll [SCEV] See through op.with.overflow intrinsics (re-apply) 2016-05-29 00:34:42 +00:00
pointer-sign-bits.ll
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pr3909.ll
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pr18606-min-zeros.ll [SCEV] Cache results during GetMinTrailingZeros query 2017-02-14 15:53:12 +00:00
pr18606.ll [SCEV] Memoize visitMulExpr results in SCEVRewriteVisitor. 2016-10-21 20:05:21 +00:00
pr22179.ll [opaque pointer type] Add textual IR support for explicit type parameter to gep operator 2015-03-13 18:20:45 +00:00
pr22641.ll Fix bug 22641 2015-02-24 01:02:42 +00:00
pr22674.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
pr22856.ll [SCEV] Fix PR22856. 2015-03-13 18:31:19 +00:00
pr24757.ll [SCEV] Make getUDivExactExpr handle non-nuw multiplies correctly. 2017-01-18 23:56:42 +00:00
pr25369.ll [SCEV] Fix PR25369 2015-11-02 02:06:01 +00:00
pr27315.ll [SCEV] Don't always add no-wrap flags to post-inc add recs 2016-05-29 00:32:17 +00:00
pr28705.ll Fix the runtime error caused by "Use ValueOffsetPair to enhance value reuse during SCEV expansion". 2016-08-09 20:40:03 +00:00
predicated-trip-count.ll Re-commit [SCEV] Introduce a guarded backedge taken count and use it in LAA and LV 2016-04-08 14:29:09 +00:00
range-signedness.ll [SCEV] Unify getUnsignedRange and getSignedRange 2015-03-09 21:43:43 +00:00
returned.ll Teach SCEV to look through returned-argument functions 2016-07-11 02:48:23 +00:00
scev-aa.ll [PM/AA] Wire up SCEVAA to the new pass manager's registry and test it. 2016-02-20 04:01:45 +00:00
scev-canonical-mode.ll This patch is to fix PR26529 caused by r259736. 2016-02-09 00:07:08 +00:00
scev-dispositions.ll [SCEV] Tweak the output format and content of -analyze 2016-05-03 17:49:57 +00:00
scev-expander-existing-value-offset.ll Recommit "Use ValueOffsetPair to enhance value reuse during SCEV expansion". 2016-08-09 20:37:50 +00:00
scev-expander-incorrect-nowrap.ll Bugfix: SCEVExpander incorrectly marks increment operations as no-wrap 2015-02-25 20:02:59 +00:00
scev-expander-reuse-gep.ll Create a getelementptr instead of sub expr for ValueOffsetPair if the 2016-09-14 04:39:50 +00:00
scev-expander-reuse-unroll.ll [UNROLL] Postpone ScalarEvolution::forgetLoop after TripCountSC is expanded 2016-08-25 16:17:18 +00:00
scev-expander-reuse-vect.ll [UNROLL] Postpone ScalarEvolution::forgetLoop after TripCountSC is expanded 2016-08-25 16:17:18 +00:00
scev-invalid.ll
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scev-prestart-nowrap.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
sext-inreg.ll [SCEV] Simplify/generalize howFarToZero solving. 2017-01-31 00:42:42 +00:00
sext-iv-0.ll [SCEV] Add a `scalar-evolution-print-constant-ranges' option 2015-03-09 21:43:39 +00:00
sext-iv-1.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
sext-iv-2.ll [opaque pointer type] Add textual IR support for explicit type parameter to gep operator 2015-03-13 18:20:45 +00:00
sext-mul.ll Model ashr(shl(x, n), m) as mul(x, 2^(n-m)) when n > m 2017-03-23 18:06:09 +00:00
sext-to-zext.ll [SCEV] Be less eager about demoting zexts to sexts 2016-03-03 18:31:23 +00:00
sext-zero.ll Model ashr(shl(x, n), m) as mul(x, 2^(n-m)) when n > m 2017-03-23 18:06:09 +00:00
shift-op.ll [SCEV] Compute max backedge count for loops with "shift ivs" 2015-10-28 21:27:14 +00:00
sle.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
smax-br-phi-idioms.ll [SCEV] Don't infinitely recurse on unreachable code 2016-08-05 18:34:14 +00:00
smax.ll
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trip-count-pow2.ll [SCEV] Clarify behavior around max backedge taken count 2017-05-22 06:46:04 +00:00
trip-count-switch.ll
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trip-count-unknown-stride.ll Reapplying r278731 after fixing the problem that caused it to be reverted. 2016-09-16 14:38:13 +00:00
trip-count.ll Be wary of abnormal exits from loop when exploiting UB 2016-06-09 01:13:59 +00:00
trip-count2.ll [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction 2015-02-27 19:29:02 +00:00
trip-count3.ll Revert "Change memcpy/memset/memmove to have dest and source alignments." 2015-11-19 05:56:52 +00:00
trip-count4.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
trip-count5.ll [SCEV] Un-grep'ify tests; NFC 2016-08-05 20:33:49 +00:00
trip-count6.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
trip-count7.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
trip-count8.ll
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trip-count9.ll
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trip-count10.ll
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trip-count11.ll [SCEV] Add a `scalar-evolution-print-constant-ranges' option 2015-03-09 21:43:39 +00:00
trip-count12.ll [opaque pointer type] Add textual IR support for explicit type parameter to load instruction 2015-02-27 21:17:42 +00:00
trip-count13.ll [LoopUnroll] Keep the loop test only on the first iteration of max-or-zero loops 2016-10-21 11:08:48 +00:00
trip-count14.ll [LoopUnroll] Keep the loop test only on the first iteration of max-or-zero loops 2016-10-21 11:08:48 +00:00
tripmultiple_calculation.ll [SCEV] Fix trip multiple calculation 2017-03-20 20:25:46 +00:00
undefined.ll
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unreachable-code.ll
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unsimplified-loop.ll
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urem-0.ll [SCEV] Add URem support to SCEV 2017-09-01 14:59:59 +00:00
zext-signed-addrec.ll [opaque pointer type] Add textual IR support for explicit type parameter to the call instruction 2015-04-16 23:24:18 +00:00
zext-wrap.ll [SCEV] Compute affine range in another way to avoid bitwidth extending. 2017-03-16 21:07:38 +00:00