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2019-07-29[DivergenceAnalysis] Add methods for querying divergence at useJay Foad1-0/+10
Summary: The existing isDivergent(Value) methods query whether a value is divergent at its definition. However even if a value is uniform at its definition, a use of it in another basic block can be divergent because of divergent control flow between the def and the use. This patch adds new isDivergent(Use) methods to DivergenceAnalysis, LegacyDivergenceAnalysis and GPUDivergenceAnalysis. This might allow D63953 or other similar workarounds to be removed. Reviewers: alex-t, nhaehnle, arsenm, rtaylor, rampitec, simoll, jingyue Reviewed By: nhaehnle Subscribers: jfb, jvesely, wdng, hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D65141 llvm-svn: 367218
2019-01-19Update the file headers across all of the LLVM projects in the monorepoChandler Carruth1-4/+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
2018-11-30[DA] GPUDivergenceAnalysis for unstructured GPU kernelsNicolai Haehnle1-0/+33
Summary: This is patch #3 of the new DivergenceAnalysis <https://lists.llvm.org/pipermail/llvm-dev/2018-May/123606.html> The GPUDivergenceAnalysis is intended to eventually supersede the existing LegacyDivergenceAnalysis. The existing LegacyDivergenceAnalysis produces incorrect results on unstructured Control-Flow Graphs: <https://bugs.llvm.org/show_bug.cgi?id=37185> This patch adds the option -use-gpu-divergence-analysis to the LegacyDivergenceAnalysis to turn it into a transparent wrapper for the GPUDivergenceAnalysis. Reviewers: nhaehnle Reviewed By: nhaehnle Subscribers: jholewinski, jvesely, jfb, llvm-commits, alex-t, sameerds, arsenm, nhaehnle Differential Revision: https://reviews.llvm.org/D53493 llvm-svn: 348048
2018-10-19[TI removal] Switch some newly added code over to use `Instruction`Chandler Carruth1-6/+5
directly. llvm-svn: 344768
2018-10-18[DA] DivergenceAnalysis for unstructured, reducible CFGsNicolai Haehnle1-0/+425
Summary: This is patch 2 of the new DivergenceAnalysis (https://reviews.llvm.org/D50433). This patch contains a generic divergence analysis implementation for unstructured, reducible Control-Flow Graphs. It contains two new classes. The `SyncDependenceAnalysis` class lazily computes sync dependences, which relate divergent branches to points of joining divergent control. The `DivergenceAnalysis` class contains the generic divergence analysis implementation. Reviewers: nhaehnle Reviewed By: nhaehnle Subscribers: sameerds, kristina, nhaehnle, xbolva00, tschuett, mgorny, llvm-commits Differential Revision: https://reviews.llvm.org/D51491 llvm-svn: 344734
2018-08-30[NFC] Rename the DivergenceAnalysis to LegacyDivergenceAnalysisNicolai Haehnle1-340/+0
Summary: This is patch 1 of the new DivergenceAnalysis (https://reviews.llvm.org/D50433). The purpose of this patch is to free up the name DivergenceAnalysis for the new generic implementation. The generic implementation class will be shared by specialized divergence analysis classes. Patch by: Simon Moll Reviewed By: nhaehnle Subscribers: jvesely, jholewinski, arsenm, nhaehnle, mgorny, jfb, llvm-commits Differential Revision: https://reviews.llvm.org/D50434 Change-Id: Ie8146b11be2c50d5312f30e11c7a3036a15b48cb llvm-svn: 341071
2018-07-13DivergenceAnalysis: added debug outputTim Renouf1-5/+16
Summary: This commit does two things: 1. modified the existing DivergenceAnalysis::dump() so it dumps the whole function with added DIVERGENT: annotations; 2. added code to do that dump if the appropriate -debug-only option is on. Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D47700 Change-Id: Id97b605aab1fc6f5a11a20c58a99bbe8c565bf83 llvm-svn: 336998
2017-12-13Remove redundant includes from lib/Analysis.Michael Zolotukhin1-1/+0
llvm-svn: 320617
2017-06-15DivergencyAnalysis patch for reviewAlexander Timofeev1-1/+1
llvm-svn: 305494
2016-05-09DivergenceAnalysis: Fix crash with no return blocksMatt Arsenault1-1/+7
The post dominator tree does not have a root node in this case. llvm-svn: 268933
2016-04-29DivergenceAnalysis: Fix crash with unreachable blocksMatt Arsenault1-0/+5
Unreachable blocks may not be in the dominator tree, so don't crash on them. llvm-svn: 268001
2016-04-18[NFC] Header cleanupMehdi Amini1-1/+0
Removed some unused headers, replaced some headers with forward class declarations. Found using simple scripts like this one: clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap' Patch by Eugene Kosov <claprix@yandex.ru> Differential Revision: http://reviews.llvm.org/D19219 From: Mehdi Amini <mehdi.amini@apple.com> llvm-svn: 266595
2016-04-14[DivergenceAnalysis] Treat PHI with incoming undef as constantNicolai Haehnle1-1/+1
Summary: If a PHI has an incoming undef, we can pretend that it is equal to one non-undef, non-self incoming value. This is particularly relevant in combination with the StructurizeCFG pass, which introduces PHI nodes with undefs. Previously, this lead to branch conditions that were uniform before StructurizeCFG to become non-uniform afterwards, which confused the SIAnnotateControlFlow pass. This fixes a crash when Mesa radeonsi compiles a shader from dEQP-GLES3.functional.shaders.switch.switch_in_for_loop_dynamic_vertex Reviewers: arsenm, tstellarAMD, jingyue Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D19013 llvm-svn: 266347
2016-02-25Introduce analysis pass to compute PostDominators in the new pass manager. NFCHongbin Zheng1-3/+4
Differential Revision: http://reviews.llvm.org/D17537 llvm-svn: 261902
2016-02-25Revert "Introduce analysis pass to compute PostDominators in the new pass ↵Hongbin Zheng1-4/+3
manager. NFC" This reverts commit a3e5cc6a51ab5ad88d1760c63284294a4e34c018. llvm-svn: 261891
2016-02-25Introduce analysis pass to compute PostDominators in the new pass manager. NFCHongbin Zheng1-3/+4
Differential Revision: http://reviews.llvm.org/D17537 llvm-svn: 261882
2016-01-27Make some headers self-contained, remove unused includes that violate layering.Benjamin Kramer1-1/+0
llvm-svn: 258937
2015-12-18[DivergenceAnalysis] fix a bug in computing influence regionsJingyue Wu1-7/+19
Fixes PR25864 llvm-svn: 256036
2015-10-10Analysis: Remove implicit ilist iterator conversionsDuncan P. N. Exon Smith1-2/+2
Remove implicit ilist iterator conversions from LLVMAnalysis. I came across something really scary in `llvm::isKnownNotFullPoison()` which relied on `Instruction::getNextNode()` being completely broken (not surprising, but scary nevertheless). This function is documented (and coded to) return `nullptr` when it gets to the sentinel, but with an `ilist_half_node` as a sentinel, the sentinel check looks into some other memory and we don't recognize we've hit the end. Rooting out these scary cases is the reason I'm removing the implicit conversions before doing anything else with `ilist`; I'm not at all surprised that clients rely on badness. I found another scary case -- this time, not relying on badness, just bad (but I guess getting lucky so far) -- in `ObjectSizeOffsetEvaluator::compute_()`. Here, we save out the insertion point, do some things, and then restore it. Previously, we let the iterator auto-convert to `Instruction*`, and then set it back using the `Instruction*` version: Instruction *PrevInsertPoint = Builder.GetInsertPoint(); /* Logic that may change insert point */ if (PrevInsertPoint) Builder.SetInsertPoint(PrevInsertPoint); The check for `PrevInsertPoint` doesn't protect correctly against bad accesses. If the insertion point has been set to the end of a basic block (i.e., `SetInsertPoint(SomeBB)`), then `GetInsertPoint()` returns an iterator pointing at the list sentinel. The version of `SetInsertPoint()` that's getting called will then call `PrevInsertPoint->getParent()`, which explodes horribly. The only reason this hasn't blown up is that it's fairly unlikely the builder is adding to the end of the block; usually, we're adding instructions somewhere before the terminator. llvm-svn: 249925
2015-09-21[DivergenceAnalysis] Separated definition of class into header.Marcello Maggioni1-54/+25
The definition of the DivergenceAnalysis pass was in a CPP file and wasn't accessible to users of the analysis to get it through "getAnalysis<>()". This patch extracts the definition into a separate header that can be used by users of the analysis to fetch the results. Patch by Volkan Keles (vkeles@apple.com) llvm-svn: 248186
2015-08-06Rename inst_range() to instructions() for consistency. NFCNico Rieck1-3/+3
llvm-svn: 244248
2015-06-23Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)Alexander Kornienko1-1/+1
Apparently, the style needs to be agreed upon first. llvm-svn: 240390
2015-06-19Fixed/added namespace ending comments using clang-tidy. NFCAlexander Kornienko1-1/+1
The patch is generated using this command: tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \ -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \ llvm/lib/ Thanks to Eugene Kosov for the original patch! llvm-svn: 240137
2015-04-10Divergence analysis for GPU programsJingyue Wu1-0/+337
Summary: Some optimizations such as jump threading and loop unswitching can negatively affect performance when applied to divergent branches. The divergence analysis added in this patch conservatively estimates which branches in a GPU program can diverge. This information can then help LLVM to run certain optimizations selectively. Test Plan: test/Analysis/DivergenceAnalysis/NVPTX/diverge.ll Reviewers: resistor, hfinkel, eliben, meheff, jholewinski Subscribers: broune, bjarke.roune, madhur13490, tstellarAMD, dberlin, echristo, jholewinski, llvm-commits Differential Revision: http://reviews.llvm.org/D8576 llvm-svn: 234567
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