summaryrefslogtreecommitdiffstats
path: root/llvm/lib/Transforms/Utils/LoopUtils.cpp
Commit message (Collapse)AuthorAgeFilesLines
* Change semantics of fadd/fmul vector reductions.Sander de Smalen2019-06-111-8/+4
| | | | | | | | | | | | | | | | | | | | This patch changes how LLVM handles the accumulator/start value in the reduction, by never ignoring it regardless of the presence of fast-math flags on callsites. This change introduces the following new intrinsics to replace the existing ones: llvm.experimental.vector.reduce.fadd -> llvm.experimental.vector.reduce.v2.fadd llvm.experimental.vector.reduce.fmul -> llvm.experimental.vector.reduce.v2.fmul and adds functionality to auto-upgrade existing LLVM IR and bitcode. Reviewers: RKSimon, greened, dmgreen, nikic, simoll, aemerson Reviewed By: nikic Differential Revision: https://reviews.llvm.org/D60261 llvm-svn: 363035
* [LoopUtils][SLPVectorizer] clean up management of fast-math-flagsSanjay Patel2019-06-051-31/+21
| | | | | | | | | | | | | | | | Instead of passing around fast-math-flags as a parameter, we can set those using an IRBuilder guard object. This is no-functional-change-intended. The motivation is to eventually fix the vectorizers to use and set the correct fast-math-flags for reductions. Examples of that not behaving as expected are: https://bugs.llvm.org/show_bug.cgi?id=23116 (should be able to reduce with less than 'fast') https://bugs.llvm.org/show_bug.cgi?id=35538 (possible miscompile for -0.0) D61802 (should be able to reduce with IR-level FMF) Differential Revision: https://reviews.llvm.org/D62272 llvm-svn: 362612
* [NFC][Utils] deleteDeadLoop(): add an assert that exit block has some ↵Roman Lebedev2019-05-051-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | non-PHI instruction Summary: If `deleteDeadLoop()` is called on such a loop, that has "bad" exit block, one that e.g. has no terminator instruction, the `DIBuilder::insertDbgValueIntrinsic()` will be told to insert the Dbg Value Intrinsic after `nullptr` (since there is no first non-PHI instruction), which will cause it to not insert those instructions into any basic block. The instructions will be parent-less, and IR verifier will complain. It is rather obvious to track down the root cause when that happens, so let's just assert it never happens. Reviewers: sanjoy, davide, vsk Reviewed By: vsk Subscribers: llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D61008 llvm-svn: 359993
* Reland "Relax constraints for reduction vectorization"Sanjoy Das2019-03-121-20/+26
| | | | | | | | | | | | | | | | | | | | | Change from original commit: move test (that uses an X86 triple) into the X86 subdirectory. Original description: Gating vectorizing reductions on *all* fastmath flags seems unnecessary; `reassoc` should be sufficient. Reviewers: tvvikram, mkuper, kristof.beyls, sdesmalen, Ayal Reviewed By: sdesmalen Subscribers: dcaballe, huntergr, jmolloy, mcrosier, jlebar, bixia, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D57728 llvm-svn: 355889
* Revert "Relax constraints for reduction vectorization"Sanjoy Das2019-03-111-26/+20
| | | | | | This reverts commit r355868. Breaks hexagon. llvm-svn: 355873
* Relax constraints for reduction vectorizationSanjoy Das2019-03-111-20/+26
| | | | | | | | | | | | | | | | | | Summary: Gating vectorizing reductions on *all* fastmath flags seems unnecessary; `reassoc` should be sufficient. Reviewers: tvvikram, mkuper, kristof.beyls, sdesmalen, Ayal Reviewed By: sdesmalen Subscribers: dcaballe, huntergr, jmolloy, mcrosier, jlebar, bixia, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D57728 llvm-svn: 355868
* [DTU] Deprecate insertEdge*/deleteEdge*Chijun Sima2019-02-221-4/+3
| | | | | | | | | | | | | | | | Summary: This patch converts all existing `insertEdge*/deleteEdge*` to `applyUpdates` and marks `insertEdge*/deleteEdge*` as deprecated. Reviewers: kuhar, brzycki Reviewed By: kuhar, brzycki Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D58443 llvm-svn: 354652
* [MemorySSA & LoopPassManager] Update MemorySSA in formDedicatedExitBlocks.Alina Sbirlea2019-02-211-1/+3
| | | | | | | MemorySSA is now updated when forming dedicated exit blocks. Resolves PR40037. llvm-svn: 354623
* Implementation of asm-goto support in LLVMCraig Topper2019-02-081-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | This patch accompanies the RFC posted here: http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html This patch adds a new CallBr IR instruction to support asm-goto inline assembly like gcc as used by the linux kernel. This instruction is both a call instruction and a terminator instruction with multiple successors. Only inline assembly usage is supported today. This also adds a new INLINEASM_BR opcode to SelectionDAG and MachineIR to represent an INLINEASM block that is also considered a terminator instruction. There will likely be more bug fixes and optimizations to follow this, but we felt it had reached a point where we would like to switch to an incremental development model. Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii Differential Revision: https://reviews.llvm.org/D53765 llvm-svn: 353563
* Move DomTreeUpdater from IR to AnalysisRichard Trieu2019-02-061-1/+1
| | | | | | | | DomTreeUpdater depends on headers from Analysis, but is in IR. This is a layering violation since Analysis depends on IR. Relocate this code from IR to Analysis to fix the layering violation. llvm-svn: 353265
* [WarnMissedTransforms] Do not warn about already vectorized loops.Michael Kruse2019-02-041-7/+7
| | | | | | | | | | | | | LoopVectorize adds llvm.loop.isvectorized, but leaves llvm.loop.vectorize.enable. Do not consider such a loop for user-forced vectorization since vectorization already happened -- by prioritizing llvm.loop.isvectorized except for TM_SuppressedByUser. Fixes http://llvm.org/PR40546 Differential Revision: https://reviews.llvm.org/D57542 llvm-svn: 353082
* Check bool attribute value in getOptionalBoolLoopAttribute.Alina Sbirlea2019-01-291-1/+4
| | | | | | | | | | | | | | | Summary: Check the bool value of the attribute in getOptionalBoolLoopAttribute not just its existance. Eliminates the warning noise generated when vectorization is explicitly disabled. Reviewers: Meinersbur, hfinkel, dmgreen Subscribers: jlebar, sanjoy, llvm-commits Differential Revision: https://reviews.llvm.org/D57260 llvm-svn: 352555
* Update the file headers across all of the LLVM projects in the monorepoChandler Carruth2019-01-191-4/+3
| | | | | | | | | | | | | | | | | to reflect the new license. We understand that people may be surprised that we're moving the header entirely to discuss the new license. We checked this carefully with the Foundation's lawyer and we believe this is the correct approach. Essentially, all code in the project is now made available by the LLVM project under our new license, so you will see that the license headers include that license only. Some of our contributors have contributed code under our old license, and accordingly, we have retained a copy of our old license notice in the top-level files in each project and repository. llvm-svn: 351636
* [NFC] Move some functions to LoopUtilsMax Kazantsev2019-01-151-0/+36
| | | | llvm-svn: 351179
* Introduce llvm.loop.parallel_accesses and llvm.access.group metadata.Michael Kruse2018-12-201-42/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current llvm.mem.parallel_loop_access metadata has a problem in that it uses LoopIDs. LoopID unfortunately is not loop identifier. It is neither unique (there's even a regression test assigning the some LoopID to multiple loops; can otherwise happen if passes such as LoopVersioning make copies of entire loops) nor persistent (every time a property is removed/added from a LoopID's MDNode, it will also receive a new LoopID; this happens e.g. when calling Loop::setLoopAlreadyUnrolled()). Since most loop transformation passes change the loop attributes (even if it just to mark that a loop should not be processed again as llvm.loop.isvectorized does, for the versioned and unversioned loop), the parallel access information is lost for any subsequent pass. This patch unlinks LoopIDs and parallel accesses. llvm.mem.parallel_loop_access metadata on instruction is replaced by llvm.access.group metadata. llvm.access.group points to a distinct MDNode with no operands (avoiding the problem to ever need to add/remove operands), called "access group". Alternatively, it can point to a list of access groups. The LoopID then has an attribute llvm.loop.parallel_accesses with all the access groups that are parallel (no dependencies carries by this loop). This intentionally avoid any kind of "ID". Loops that are clones/have their attributes modifies retain the llvm.loop.parallel_accesses attribute. Access instructions that a cloned point to the same access group. It is not necessary for each access to have it's own "ID" MDNode, but those memory access instructions with the same behavior can be grouped together. The behavior of llvm.mem.parallel_loop_access is not changed by this patch, but should be considered deprecated. Differential Revision: https://reviews.llvm.org/D52116 llvm-svn: 349725
* [LoopUtils] Use i32 instead of `void`.Davide Italiano2018-12-131-1/+1
| | | | | | | | The actual type of the first argument of the @dbg intrinsic doesn't really matter as we're setting it to `undef`, but the bitcode reader is picky about `void` types. llvm-svn: 349069
* [LoopUtils] Prefer a set over a map. NFCI.Davide Italiano2018-12-131-6/+4
| | | | llvm-svn: 348999
* [LoopDeletion] Update debug values after loop deletion.Davide Italiano2018-12-121-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When loops are deleted, we don't keep track of variables modified inside the loops, so the DI will contain the wrong value for these. e.g. int b() { int i; for (i = 0; i < 2; i++) ; patatino(); return a; -> 6 patatino(); 7 return a; 8 } 9 int main() { b(); } (lldb) frame var i (int) i = 0 We mark instead these values as unavailable inserting a @llvm.dbg.value(undef to make sure we don't end up printing an incorrect value in the debugger. We could consider doing something fancier, for, e.g. constants, in the future. PR39868. rdar://problem/46418795) Differential Revision: https://reviews.llvm.org/D55299 llvm-svn: 348988
* [Unroll/UnrollAndJam/Vectorizer/Distribute] Add followup loop attributes.Michael Kruse2018-12-121-16/+247
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Revert r346810 "Preserve loop metadata when splitting exit blocks"Reid Kleckner2018-11-141-32/+0
| | | | | | | It broke the Windows self-host: http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/1457 llvm-svn: 346823
* Preserve loop metadata when splitting exit blocksCraig Topper2018-11-131-0/+32
| | | | | | | | | | LoopUtils.cpp contains a utility that splits an loop exit block, so that the new block contains only edges coming from the loop. In the case of nested loops, the exit path for the inner loop might also be the back-edge of the outer loop. The new block which is inserted on this path, is now a latch for the outer loop, and it needs to hold the loop metadata for the outer loop. (The test case gives a more concrete view of the situation.) Patch by Chang Lin (clin1) Differential Revision: https://reviews.llvm.org/D53876 llvm-svn: 346810
* Break LoopUtils into an Analysis file.Vikram TV2018-09-121-988/+1
| | | | | | | | | | | | | | | | | | | Summary: The InductionDescriptor and RecurrenceDescriptor classes basically analyze the IR to identify the respective IVs. So, it is better to have them in the "Analysis" directory instead of the "Transforms" directory. The rationale for this is to make the Induction and Recurrence descriptor classes available for analysis passes. Currently including them in an analysis pass produces link error (http://lists.llvm.org/pipermail/llvm-dev/2018-July/124456.html). Induction and Recurrence descriptors are moved from Transforms/Utils/LoopUtils.h|cpp to Analysis/IVDescriptors.h|cpp. Reviewers: dmgreen, llvm-commits, hfinkel Reviewed By: dmgreen Subscribers: mgorny Differential Revision: https://reviews.llvm.org/D51153 llvm-svn: 342016
* Move a transformation routine from LoopUtils to LoopVectorize.Vikram TV2018-09-101-68/+0
| | | | | | | | | | | | | | | | Summary: Move InductionDescriptor::transform() routine from LoopUtils to its only uses in LoopVectorize.cpp. Specifically, the function is renamed as InnerLoopVectorizer::emitTransformedIndex(). This is a child to D51153. Reviewers: dmgreen, llvm-commits Reviewed By: dmgreen Differential Revision: https://reviews.llvm.org/D51837 llvm-svn: 341776
* Move createMinMaxOp() out of RecurrenceDescriptor.Vikram TV2018-09-101-48/+47
| | | | | | | | | | Reviewers: dmgreen, llvm-commits Reviewed By: dmgreen Differential Revision: https://reviews.llvm.org/D51838 llvm-svn: 341773
* Update MemorySSA in BasicBlockUtils.Alina Sbirlea2018-08-211-1/+1
| | | | | | | | | | | Summary: Extend BasicBlocksUtils to update MemorySSA. Subscribers: sanjoy, arsenm, nhaehnle, jlebar, Prazek, llvm-commits Differential Revision: https://reviews.llvm.org/D45300 llvm-svn: 340365
* [UnJ] Rename hasInvariantIterationCount to ↵David Green2018-08-151-2/+2
| | | | | | | | hasIterationCountInvariantInParent NFC This hopefully describes the API of the function more precisely. llvm-svn: 339762
* [UnJ] Create a hasInvariantIterationCount function. NFCDavid Green2018-08-111-0/+22
| | | | | | | | | | Pulled out a separate function for some code that calculates if an inner loop iteration count is invariant to it's outer loop. Differential Revision: https://reviews.llvm.org/D50063 llvm-svn: 339500
* [Dominators] Convert existing passes and utils to use the DomTreeUpdater classChijun Sima2018-08-031-2/+4
| | | | | | | | | | | | | | | | | | Summary: This patch is the second in a series of patches related to the [[ http://lists.llvm.org/pipermail/llvm-dev/2018-June/123883.html | RFC - A new dominator tree updater for LLVM ]]. It converts passes (e.g. adce/jump-threading) and various functions which currently accept DDT in local.cpp and BasicBlockUtils.cpp to use the new DomTreeUpdater class. These converted functions in utils can accept DomTreeUpdater with either UpdateStrategy and can deal with both DT and PDT held by the DomTreeUpdater. Reviewers: brzycki, kuhar, dmgreen, grosser, davide Reviewed By: brzycki Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D48967 llvm-svn: 338814
* Rename DEBUG macro to LLVM_DEBUG.Nicola Zaghen2018-05-141-16/+19
| | | | | | | | | | | | | | | | The DEBUG() macro is very generic so it might clash with other projects. The renaming was done as follows: - git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g' - git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM - Manual change to APInt - Manually chage DOCS as regex doesn't match it. In the transition period the DEBUG() macro is still present and aliased to the LLVM_DEBUG() one. Differential Revision: https://reviews.llvm.org/D43624 llvm-svn: 332240
* Remove \brief commands from doxygen comments.Adrian Prantl2018-05-011-3/+3
| | | | | | | | | | | | | | | | We've been running doxygen with the autobrief option for a couple of years now. This makes the \brief markers into our comments redundant. Since they are a visual distraction and we don't want to encourage more \brief markers in new code either, this patch removes them all. Patch produced by for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done Differential Revision: https://reviews.llvm.org/D46290 llvm-svn: 331272
* Support generic expansion of ordered vector reduction (PR36732)Simon Pilgrim2018-04-091-0/+32
| | | | | | | | | | Without the fast math flags, the llvm.experimental.vector.reduce.fadd/fmul intrinsic expansions must be expanded in order. This patch scalarizes the reduction, applying the accumulator at the start of the sequence: ((((Acc + Scl[0]) + Scl[1]) + Scl[2]) + ) ... + Scl[NumElts-1] Differential Revision: https://reviews.llvm.org/D45366 llvm-svn: 329585
* Strip trailing whitespace. NFCI.Simon Pilgrim2018-04-061-8/+8
| | | | llvm-svn: 329421
* [MustExecute] Move isGuaranteedToExecute and related rourtines to AnalysisPhilip Reames2018-03-201-133/+1
| | | | | | Next step is to actually merge the implementations and get both implementations tested through the new printer. llvm-svn: 328055
* [LICM/mustexec] Extend first iteration must execute logic to fcmpsPhilip Reames2018-03-161-10/+9
| | | | | | | | | | This builds on the work from https://reviews.llvm.org/D44287. It turned out supporting fcmp was much easier than I realized, so let's do that now. As an aside, our -O3 handling of a floating point IVs leaves a lot to be desired. We do convert the float IV to an integer IV, but do so late enough that many other optimizations are missed (e.g. we don't vectorize). Differential Revision: https://reviews.llvm.org/D44542 llvm-svn: 327722
* [LICM] Ignore exits provably not taken on first iteration when computing ↵Philip Reames2018-03-151-1/+60
| | | | | | | | | | | | | | | | must execute It is common to have conditional exits within a loop which are known not to be taken on some iterations, but not necessarily all. This patches extends our reasoning around guaranteed to execute (used when establishing whether it's safe to dereference a location from the preheader) to handle the case where an exit is known not to be taken on the first iteration and the instruction of interest *is* known to be taken on the first iteration. This case comes up in two major ways: * If we have a range check which we've been unable to eliminate, we frequently know that it doesn't fail on the first iteration. * Pass ordering. We may have a check which will be eliminated through some sequence of other passes, but depending on the exact pass sequence we might never actually do so or we might miss other optimizations from passes run before the check is finally eliminated. The initial version (here) is implemented via InstSimplify. At the moment, it catches a few cases, but misses a lot too. I added test cases for missing cases in InstSimplify which I'll follow up on separately. Longer term, we should probably wire SCEV through to here to get much smarter loop aware simplification of the first iteration predicate. Differential Revision: https://reviews.llvm.org/D44287 llvm-svn: 327664
* [NFC] Factor out a helper function for checking if a block has a potential ↵Philip Reames2018-03-081-7/+4
| | | | | | early implicit exit. llvm-svn: 327065
* Move llvm::computeLoopSafetyInfo from LICM.cpp to LoopUtils.cpp. NFCDavid Green2018-02-141-0/+37
| | | | | | | | | Move computeLoopSafetyInfo, defined in Transforms/Utils/LoopUtils.h, into the corresponding LoopUtils.cpp, as opposed to LICM where it resides at the moment. This will allow other functions from Transforms/Utils to reference it. llvm-svn: 325151
* [LV] Use Demanded Bits and ValueTracking for reduction type-shrinkingChad Rosier2018-02-041-72/+144
| | | | | | | | | | | | | | | The type-shrinking logic in reduction detection, although narrow in scope, is also rather ad-hoc, which has led to bugs (e.g., PR35734). This patch modifies the approach to rely on the demanded bits and value tracking analyses, if available. We currently perform type-shrinking separately for reductions and other instructions in the loop. Long-term, we should probably think about computing minimal bit widths in a more complete way for the loops we want to vectorize. PR35734 Differential Revision: https://reviews.llvm.org/D42309 llvm-svn: 324195
* [NFC] fix trivial typos in commentsHiroshi Inoue2018-01-191-1/+1
| | | | | | "the the" -> "the" llvm-svn: 322934
* [LoopDeletion] Handle users in unreachable blockSerguei Katkov2018-01-121-0/+26
| | | | | | | | | | | | | | This is a fix for PR35884. When we want to delete dead loop we must clean uses in unreachable blocks otherwise we'll get an assert during deletion of instructions from the loop. Reviewers: anna, davide Reviewed By: anna Subscribers: llvm-commits, lebedev.ri Differential Revision: https://reviews.llvm.org/D41943 llvm-svn: 322357
* Use phi ranges to simplify code. No functionality change intended.Benjamin Kramer2017-12-301-8/+6
| | | | llvm-svn: 321585
* Make helpers static. No functionality change.Benjamin Kramer2017-12-241-3/+4
| | | | llvm-svn: 321425
* [LV] Support efficient vectorization of an induction with redundant castsDorit Nuzman2017-12-141-8/+133
| | | | | | | | | | | | | | | | | | | | | | | | | | | | D30041 extended SCEVPredicateRewriter to improve handling of Phi nodes whose update chain involves casts; PSCEV can now build an AddRecurrence for some forms of such phi nodes, under the proper runtime overflow test. This means that we can identify such phi nodes as an induction, and the loop-vectorizer can now vectorize such inductions, however inefficiently. The vectorizer doesn't know that it can ignore the casts, and so it vectorizes them. This patch records the casts in the InductionDescriptor, so that they could be marked to be ignored for cost calculation (we use VecValuesToIgnore for that) and ignored for vectorization/widening/scalarization (i.e. treated as TriviallyDead). In addition to marking all these casts to be ignored, we also need to make sure that each cast is mapped to the right vector value in the vector loop body (be it a widened, vectorized, or scalarized induction). So whenever an induction phi is mapped to a vector value (during vectorization/widening/ scalarization), we also map the respective cast instruction (if exists) to that vector value. (If the phi-update sequence of an induction involves more than one cast, then the above mapping to vector value is relevant only for the last cast of the sequence as we allow only the "last cast" to be used outside the induction update chain itself). This is the last step in addressing PR30654. llvm-svn: 320672
* [LoopUtils] simplify createTargetReduction(); NFCISanjay Patel2017-12-061-41/+25
| | | | llvm-svn: 319946
* [LoopUtils] fix variable name to match FMF vocabulary; NFCSanjay Patel2017-12-061-4/+4
| | | | llvm-svn: 319928
* [IR] redefine 'UnsafeAlgebra' / 'reassoc' fast-math-flags and add 'trans' ↵Sanjay Patel2017-11-061-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fast-math-flag As discussed on llvm-dev: http://lists.llvm.org/pipermail/llvm-dev/2016-November/107104.html and again more recently: http://lists.llvm.org/pipermail/llvm-dev/2017-October/118118.html ...this is a step in cleaning up our fast-math-flags implementation in IR to better match the capabilities of both clang's user-visible flags and the backend's flags for SDNode. As proposed in the above threads, we're replacing the 'UnsafeAlgebra' bit (which had the 'umbrella' meaning that all flags are set) with a new bit that only applies to algebraic reassociation - 'AllowReassoc'. We're also adding a bit to allow approximations for library functions called 'ApproxFunc' (this was initially proposed as 'libm' or similar). ...and we're out of bits. 7 bits ought to be enough for anyone, right? :) FWIW, I did look at getting this out of SubclassOptionalData via SubclassData (spacious 16-bits), but that's apparently already used for other purposes. Also, I don't think we can just add a field to FPMathOperator because Operator is not intended to be instantiated. We'll defer movement of FMF to another day. We keep the 'fast' keyword. I thought about removing that, but seeing IR like this: %f.fast = fadd reassoc nnan ninf nsz arcp contract afn float %op1, %op2 ...made me think we want to keep the shortcut synonym. Finally, this change is binary incompatible with existing IR as seen in the compatibility tests. This statement: "Newer releases can ignore features from older releases, but they cannot miscompile them. For example, if nsw is ever replaced with something else, dropping it would be a valid way to upgrade the IR." ( http://llvm.org/docs/DeveloperPolicy.html#ir-backwards-compatibility ) ...provides the flexibility we want to make this change without requiring a new IR version. Ie, we're not loosening the FP strictness of existing IR. At worst, we will fail to optimize some previously 'fast' code because it's no longer recognized as 'fast'. This should get fixed as we audit/squash all of the uses of 'isFast()'. Note: an inter-dependent clang commit to use the new API name should closely follow commit. Differential Revision: https://reviews.llvm.org/D39304 llvm-svn: 317488
* Fix a -Wparentheses warning. NFC.Hans Wennborg2017-10-041-1/+1
| | | | llvm-svn: 314936
* [LoopDeletion] Move deleteDeadLoop to to LoopUtils. NFCMarcello Maggioni2017-10-041-0/+122
| | | | llvm-svn: 314934
* Refactor collectChildrenInLoop to LoopUtils [NFC]Alina Sbirlea2017-09-151-0/+21
| | | | | | | | | | | | Summary: Move to LoopUtils method that collects all children of a node inside a loop. Reviewers: majnemer, sanjoy Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D37870 llvm-svn: 313322
* [LV] Minor savings to Sink casts to unravel first order recurrenceAyal Zaks2017-08-151-1/+2
| | | | | | | | | Two minor savings: avoid copying the SinkAfter map and avoid moving a cast if it is not needed. Differential Revision: https://reviews.llvm.org/D36408 llvm-svn: 310910
OpenPOWER on IntegriCloud