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Revision tags: llvmorg-20.1.0, llvmorg-20.1.0-rc3, llvmorg-20.1.0-rc2, llvmorg-20.1.0-rc1, llvmorg-21-init, llvmorg-19.1.7, llvmorg-19.1.6, llvmorg-19.1.5, llvmorg-19.1.4, llvmorg-19.1.3, llvmorg-19.1.2, llvmorg-19.1.1, llvmorg-19.1.0, llvmorg-19.1.0-rc4, llvmorg-19.1.0-rc3, llvmorg-19.1.0-rc2, llvmorg-19.1.0-rc1, llvmorg-20-init, llvmorg-18.1.8, llvmorg-18.1.7, llvmorg-18.1.6, llvmorg-18.1.5, llvmorg-18.1.4, llvmorg-18.1.3, llvmorg-18.1.2, llvmorg-18.1.1, llvmorg-18.1.0, llvmorg-18.1.0-rc4, llvmorg-18.1.0-rc3, llvmorg-18.1.0-rc2, llvmorg-18.1.0-rc1, llvmorg-19-init, llvmorg-17.0.6, llvmorg-17.0.5, llvmorg-17.0.4, llvmorg-17.0.3, llvmorg-17.0.2, llvmorg-17.0.1, llvmorg-17.0.0, llvmorg-17.0.0-rc4, llvmorg-17.0.0-rc3, llvmorg-17.0.0-rc2, llvmorg-17.0.0-rc1, llvmorg-18-init, llvmorg-16.0.6, llvmorg-16.0.5, llvmorg-16.0.4, llvmorg-16.0.3, llvmorg-16.0.2, llvmorg-16.0.1, llvmorg-16.0.0, llvmorg-16.0.0-rc4, llvmorg-16.0.0-rc3, llvmorg-16.0.0-rc2, llvmorg-16.0.0-rc1, llvmorg-17-init, llvmorg-15.0.7, llvmorg-15.0.6, llvmorg-15.0.5, llvmorg-15.0.4, llvmorg-15.0.3, llvmorg-15.0.2, llvmorg-15.0.1, llvmorg-15.0.0, llvmorg-15.0.0-rc3, llvmorg-15.0.0-rc2, llvmorg-15.0.0-rc1, llvmorg-16-init, llvmorg-14.0.6, llvmorg-14.0.5, llvmorg-14.0.4, llvmorg-14.0.3, llvmorg-14.0.2, llvmorg-14.0.1, llvmorg-14.0.0, llvmorg-14.0.0-rc4, llvmorg-14.0.0-rc3, llvmorg-14.0.0-rc2, llvmorg-14.0.0-rc1, llvmorg-15-init, llvmorg-13.0.1, llvmorg-13.0.1-rc3, llvmorg-13.0.1-rc2, llvmorg-13.0.1-rc1, llvmorg-13.0.0, llvmorg-13.0.0-rc4, llvmorg-13.0.0-rc3 |
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50153213 |
| 01-Sep-2021 |
Arthur Eubanks <[email protected]> |
[test][NewPM] Remove RUN lines using -analyze
Only tests in llvm/test/Analysis.
-analyze is legacy PM-specific.
This only touches files with `-passes`.
I looked through everything and made sure t
[test][NewPM] Remove RUN lines using -analyze
Only tests in llvm/test/Analysis.
-analyze is legacy PM-specific.
This only touches files with `-passes`.
I looked through everything and made sure that everything had a new PM equivalent.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D109040
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Revision tags: llvmorg-13.0.0-rc2, llvmorg-13.0.0-rc1, llvmorg-14-init, llvmorg-12.0.1, llvmorg-12.0.1-rc4, llvmorg-12.0.1-rc3, llvmorg-12.0.1-rc2, llvmorg-12.0.1-rc1, llvmorg-12.0.0, llvmorg-12.0.0-rc5, llvmorg-12.0.0-rc4, llvmorg-12.0.0-rc3, llvmorg-12.0.0-rc2, llvmorg-11.1.0, llvmorg-11.1.0-rc3, llvmorg-12.0.0-rc1, llvmorg-13-init, llvmorg-11.1.0-rc2, llvmorg-11.1.0-rc1, llvmorg-11.0.1, llvmorg-11.0.1-rc2, llvmorg-11.0.1-rc1, llvmorg-11.0.0, llvmorg-11.0.0-rc6, llvmorg-11.0.0-rc5, llvmorg-11.0.0-rc4, llvmorg-11.0.0-rc3, llvmorg-11.0.0-rc2, llvmorg-11.0.0-rc1, llvmorg-12-init, llvmorg-10.0.1, llvmorg-10.0.1-rc4, llvmorg-10.0.1-rc3, llvmorg-10.0.1-rc2 |
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9fb074e7 |
| 18-Jun-2020 |
Evgeniy Brevnov <[email protected]> |
[BPI] Improve static heuristics for "cold" paths.
Current approach doesn't work well in cases when multiple paths are predicted to be "cold". By "cold" paths I mean those containing "unreachable" in
[BPI] Improve static heuristics for "cold" paths.
Current approach doesn't work well in cases when multiple paths are predicted to be "cold". By "cold" paths I mean those containing "unreachable" instruction, call marked with 'cold' attribute and 'unwind' handler of 'invoke' instruction. The issue is that heuristics are applied one by one until the first match and essentially ignores relative hotness/coldness of other paths.
New approach unifies processing of "cold" paths by assigning predefined absolute weight to each block estimated to be "cold". Then we propagate these weights up/down IR similarly to existing approach. And finally set up edge probabilities based on estimated block weights.
One important difference is how we propagate weight up. Existing approach propagates the same weight to all blocks that are post-dominated by a block with some "known" weight. This is useless at least because it always gives 50\50 distribution which is assumed by default anyway. Worse, it causes the algorithm to skip further heuristics and can miss setting more accurate probability. New algorithm propagates the weight up only to the blocks that dominates and post-dominated by a block with some "known" weight. In other words, those blocks that are either always executed or not executed together.
In addition new approach processes loops in an uniform way as well. Essentially loop exit edges are estimated as "cold" paths relative to back edges and should be considered uniformly with other coldness/hotness markers.
Reviewed By: yrouban
Differential Revision: https://reviews.llvm.org/D79485
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5c31b8b9 |
| 31-Oct-2020 |
Arthur Eubanks <[email protected]> |
Revert "Use uint64_t for branch weights instead of uint32_t"
This reverts commit 10f2a0d662d8d72eaac48d3e9b31ca8dc90df5a4.
More uint64_t overflows.
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10f2a0d6 |
| 30-Sep-2020 |
Arthur Eubanks <[email protected]> |
Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32. To be more consistent everywhere and remove lots of casts from uint64
Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32. To be more consistent everywhere and remove lots of casts from uint64_t to uint32_t, use i64 for branch_weights.
Reviewed By: davidxl
Differential Revision: https://reviews.llvm.org/D88609
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2a4e704c |
| 27-Oct-2020 |
Nico Weber <[email protected]> |
Revert "Use uint64_t for branch weights instead of uint32_t"
This reverts commit e5766f25c62c185632e3a75bf45b313eadab774b. Makes clang assert when building Chromium, see https://crbug.com/1142813 fo
Revert "Use uint64_t for branch weights instead of uint32_t"
This reverts commit e5766f25c62c185632e3a75bf45b313eadab774b. Makes clang assert when building Chromium, see https://crbug.com/1142813 for a repro.
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e5766f25 |
| 30-Sep-2020 |
Arthur Eubanks <[email protected]> |
Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32. To be more consistent everywhere and remove lots of casts from uint64
Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32. To be more consistent everywhere and remove lots of casts from uint64_t to uint32_t, use i64 for branch_weights.
Reviewed By: davidxl
Differential Revision: https://reviews.llvm.org/D88609
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84a8ca1e |
| 17-Sep-2020 |
Arthur Eubanks <[email protected]> |
[NewPM] Pin -lazy-branch-prob and -lazy-block-freq tests to legacy PM
NPM passes just use the normal versions of these analyses instead. Also pin any tests with -analyze to legacy PM.
Reviewed By:
[NewPM] Pin -lazy-branch-prob and -lazy-block-freq tests to legacy PM
NPM passes just use the normal versions of these analyses instead. Also pin any tests with -analyze to legacy PM.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D87857
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dcfa78a4 |
| 04-Jun-2020 |
Yevgeny Rouban <[email protected]> |
Extend InvokeInst !prof branch_weights metadata to unwind branches
Allow InvokeInst to have the second optional prof branch weight for its unwind branch. InvokeInst is a terminator with two successo
Extend InvokeInst !prof branch_weights metadata to unwind branches
Allow InvokeInst to have the second optional prof branch weight for its unwind branch. InvokeInst is a terminator with two successors. It might have its unwind branch taken many times. If so the BranchProbabilityInfo unwind branch heuristic can be inaccurate. This patch allows a higher accuracy calculated with both branch weights set.
Changes: - A new section about InvokeInst is added to the BranchWeightMetadata page. It states the old information that missed in the doc and adds new about the second branch weight. - Verifier is changed to allow either 1 or 2 branch weights for InvokeInst. - A new test is written for BranchProbabilityInfo to demonstrate the main improvement of the simple fix in calcMetadataWeights(). - Several new testcases are created for Inliner. Those check that both weights are accounted for invoke instruction weight calculation. - PGOUseFunc::setBranchWeights() is fixed to be applicable to InvokeInst.
Reviewers: davidxl, reames, xur, yamauchi Tags: #llvm Differential Revision: https://reviews.llvm.org/D80618
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07239c73 |
| 02-Jun-2020 |
Yevgeny Rouban <[email protected]> |
[BrachProbablityInfo] Proportional distribution of reachable probabilities
When fixing probability of unreachable edges in BranchProbabilityInfo::calcMetadataWeights() proportionally distribute rema
[BrachProbablityInfo] Proportional distribution of reachable probabilities
When fixing probability of unreachable edges in BranchProbabilityInfo::calcMetadataWeights() proportionally distribute remainder probability over the reachable edges. The old implementation distributes the remainder probability evenly. See examples in the fixed tests.
Reviewers: yamauchi, ebrevnov Tags: #llvm Differential Revision: https://reviews.llvm.org/D80611
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81384874 |
| 21-May-2020 |
Yevgeny Rouban <[email protected]> |
[BrachProbablityInfo] Set edge probabilities at once and fix calcMetadataWeights()
Hide the method that allows setting probability for particular edge and introduce a public method that sets probabi
[BrachProbablityInfo] Set edge probabilities at once and fix calcMetadataWeights()
Hide the method that allows setting probability for particular edge and introduce a public method that sets probabilities for all outgoing edges at once. Setting individual edge probability is error prone. More over it is difficult to check that the total probability is 1.0 because there is no easy way to know when the user finished setting all the probabilities.
Related bug is fixed in BranchProbabilityInfo::calcMetadataWeights(). Changing unreachable branch probabilities to raw(1) and distributing the rest (oldProbability - raw(1)) over the reachable branches could introduce total probability inaccuracy bigger than 1/numOfBranches.
Reviewers: yamauchi, ebrevnov Tags: #llvm Differential Revision: https://reviews.llvm.org/D79396
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Revision tags: llvmorg-10.0.1-rc1, llvmorg-10.0.0, llvmorg-10.0.0-rc6, llvmorg-10.0.0-rc5, llvmorg-10.0.0-rc4, llvmorg-10.0.0-rc3, llvmorg-10.0.0-rc2, llvmorg-10.0.0-rc1, llvmorg-11-init, llvmorg-9.0.1, llvmorg-9.0.1-rc3, llvmorg-9.0.1-rc2 |
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2da205d4 |
| 02-Dec-2019 |
Taewook Oh <[email protected]> |
Reland "b19ec1eb3d0c [BPI] Improve unreachable/ColdCall heurstics to handle loops."
Summary: b19ec1eb3d0c has been reverted because of the test failures with PowerPC targets. This patch addresses th
Reland "b19ec1eb3d0c [BPI] Improve unreachable/ColdCall heurstics to handle loops."
Summary: b19ec1eb3d0c has been reverted because of the test failures with PowerPC targets. This patch addresses the issues from the previous commit.
Test Plan: ninja check-all. Confirmed that CodeGen/PowerPC/pr36292.ll and CodeGen/PowerPC/sms-cpy-1.ll pass
Subscribers: llvm-commits
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5d21f75b |
| 27-Nov-2019 |
taewookoh <[email protected]> |
Revert b19ec1eb3d0c
Summary: This reverts commit b19ec1eb3d0c as it fails powerpc tests
Subscribers: llvm-commits
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b19ec1eb |
| 27-Nov-2019 |
Taewook Oh <[email protected]> |
[BPI] Improve unreachable/ColdCall heurstics to handle loops.
Summary: While updatePostDominatedByUnreachable attemps to find basic blocks that are post-domianted by unreachable blocks, it currently
[BPI] Improve unreachable/ColdCall heurstics to handle loops.
Summary: While updatePostDominatedByUnreachable attemps to find basic blocks that are post-domianted by unreachable blocks, it currently cannot handle loops precisely, because it doesn't use the actual post dominator tree analysis but relies on heuristics of visiting basic blocks in post-order. More precisely, when the entire loop is post-dominated by the unreachable block, current algorithm fails to detect the entire loop as post-dominated by the unreachable because when the algorithm reaches to the loop latch it fails to tell all its successors (including the loop header) will "eventually" be post-domianted by the unreachable block, because the algorithm hasn't visited the loop header yet. This makes BPI for the loop latch to assume that loop backedges are taken with 100% of probability. And because of this, block frequency info sometimes marks virtually dead loops (which are post dominated by unreachable blocks) super hot, because 100% backedge-taken probability makes the loop iteration count the max value. updatePostDominatedByColdCall has the exact same problem as well.
To address this problem, this patch makes PostDominatedByUnreachable/PostDominatedByColdCall to be computed with the actual post-dominator tree.
Reviewers: skatkov, chandlerc, manmanren
Reviewed By: skatkov
Subscribers: manmanren, vsk, apilipenko, Carrot, qcolombet, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70104
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Revision tags: llvmorg-9.0.1-rc1, llvmorg-9.0.0, llvmorg-9.0.0-rc6, llvmorg-9.0.0-rc5, llvmorg-9.0.0-rc4, llvmorg-9.0.0-rc3, llvmorg-9.0.0-rc2, llvmorg-9.0.0-rc1, llvmorg-10-init, llvmorg-8.0.1, llvmorg-8.0.1-rc4, llvmorg-8.0.1-rc3, llvmorg-8.0.1-rc2, llvmorg-8.0.1-rc1, llvmorg-8.0.0, llvmorg-8.0.0-rc5, llvmorg-8.0.0-rc4, llvmorg-8.0.0-rc3, llvmorg-7.1.0, llvmorg-7.1.0-rc1, llvmorg-8.0.0-rc2, llvmorg-8.0.0-rc1, llvmorg-7.0.1, llvmorg-7.0.1-rc3, llvmorg-7.0.1-rc2, llvmorg-7.0.1-rc1, llvmorg-7.0.0, llvmorg-7.0.0-rc3, llvmorg-7.0.0-rc2, llvmorg-7.0.0-rc1, llvmorg-6.0.1, llvmorg-6.0.1-rc3, llvmorg-6.0.1-rc2, llvmorg-6.0.1-rc1, llvmorg-5.0.2, llvmorg-5.0.2-rc2, llvmorg-5.0.2-rc1, llvmorg-6.0.0, llvmorg-6.0.0-rc3, llvmorg-6.0.0-rc2, llvmorg-6.0.0-rc1, llvmorg-5.0.1, llvmorg-5.0.1-rc3, llvmorg-5.0.1-rc2, llvmorg-5.0.1-rc1, llvmorg-5.0.0, llvmorg-5.0.0-rc5, llvmorg-5.0.0-rc4, llvmorg-5.0.0-rc3, llvmorg-5.0.0-rc2, llvmorg-5.0.0-rc1, llvmorg-4.0.1, llvmorg-4.0.1-rc3, llvmorg-4.0.1-rc2 |
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ba831f78 |
| 18-May-2017 |
Serguei Katkov <[email protected]> |
[BPI] Reduce the probability of unreachable edge to minimal value greater than 0
The probability of edge coming to unreachable block should be as low as possible. The change reduces the probability
[BPI] Reduce the probability of unreachable edge to minimal value greater than 0
The probability of edge coming to unreachable block should be as low as possible. The change reduces the probability to minimal value greater than zero.
The bug https://bugs.llvm.org/show_bug.cgi?id=32214 show the example when the probability of edge coming to unreachable block is greater than for edge coming to out of the loop and it causes incorrect loop rotation.
Please note that with this change the behavior of unreachable heuristic is a bit different than others. Specifically, before this change the sum of probabilities coming to unreachable blocks have the same weight for all branches (it was just split over all edges of this block coming to unreachable blocks). With this change it might be slightly different but not to much due to probability of taken branch to unreachable block is really small.
Reviewers: chandlerc, sanjoy, vsk, congh, junbuml, davidxl, dexonsmith Reviewed By: chandlerc, dexonsmith Subscribers: reames, llvm-commits Differential Revision: https://reviews.llvm.org/D30633
llvm-svn: 303327
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63c9c811 |
| 12-May-2017 |
Serguei Katkov <[email protected]> |
[BPI] Ignore remainder while distributing the remaining probability from unreachanble
This is a follow up patch for https://reviews.llvm.org/rL300440 to address a comment.
To make implementation to
[BPI] Ignore remainder while distributing the remaining probability from unreachanble
This is a follow up patch for https://reviews.llvm.org/rL300440 to address a comment.
To make implementation to be consistent with other cases we just ignore the remainder after distribution of remaining probability between reachable edges.
If we reduced the probability of some edges coming to unreachable blocks we should distribute the remaining part across other edges coming to reachable blocks to satisfy the condition that sum of all probabilities should be equal to one. If this remaining part is not divided by number of "reachable" edges then we get this remainder. This remainder probability should be pretty small. Other cases just ignore if the sum of probabilities is not equal to one so we do the same.
Reviewers: chandlerc, sanjoy, vsk, junbuml, reames Reviewed By: reames Subscribers: reames, llvm-commits Differential Revision: https://reviews.llvm.org/D32124
llvm-svn: 302883
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Revision tags: llvmorg-4.0.1-rc1 |
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2616bbb1 |
| 17-Apr-2017 |
Serguei Katkov <[email protected]> |
[BPI] Use metadata info before any other heuristics
Metadata potentially is more precise than any heuristics we use, so it makes sense to use first metadata info if it is available. However it makes
[BPI] Use metadata info before any other heuristics
Metadata potentially is more precise than any heuristics we use, so it makes sense to use first metadata info if it is available. However it makes sense to examine it against other strong heuristics like unreachable one. If edge coming to unreachable block has higher probability then it is expected by unreachable heuristic then we use heuristic and remaining probability is distributed among other reachable blocks equally.
An example where metadata might be more strong then unreachable heuristic is as follows: it is possible that there are two branches and for the branch A metadata says that its probability is (0, 2^25). For the branch B the probability is (1, 2^25). So the expectation is that first edge of B is hotter than first edge of A because first edge of A did not executed at least once. If first edge of A points to the unreachable block then using the unreachable heuristics we'll set the probability for A to (1, 2^20) and now edge of A becomes hotter than edge of B. This is unexpected behavior.
This fixed the biggest part of https://bugs.llvm.org/show_bug.cgi?id=32214
Reviewers: sanjoy, junbuml, vsk, chandlerc
Reviewed By: chandlerc
Subscribers: llvm-commits, reames, davidxl
Differential Revision: https://reviews.llvm.org/D30631
llvm-svn: 300440
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ecebc3db |
| 12-Apr-2017 |
Serguei Katkov <[email protected]> |
[BPI] Refactor post domination calculation and simple fix for ColdCall
Collection of PostDominatedByUnreachable and PostDominatedByColdCall have been split out of heuristics itself. Update of the da
[BPI] Refactor post domination calculation and simple fix for ColdCall
Collection of PostDominatedByUnreachable and PostDominatedByColdCall have been split out of heuristics itself. Update of the data happens now for each basic block (before update for PostDominatedByColdCall might be skipped if unreachable or matadata heuristic handled this basic block).
This separation allows re-ordering of heuristics without loosing the post-domination information.
Reviewers: sanjoy, junbuml, vsk, chandlerc, reames
Reviewed By: chandlerc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31701
llvm-svn: 300029
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Revision tags: llvmorg-4.0.0, llvmorg-4.0.0-rc4, llvmorg-4.0.0-rc3, llvmorg-4.0.0-rc2, llvmorg-4.0.0-rc1, llvmorg-3.9.1, llvmorg-3.9.1-rc3, llvmorg-3.9.1-rc2, llvmorg-3.9.1-rc1 |
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3822939b |
| 23-Sep-2016 |
Jun Bum Lim <[email protected]> |
Enhance calcColdCallHeuristics for InvokeInst
Summary: When identifying cold blocks, consider only the edge to the normal destination if the terminator is InvokeInst and let calcInvokeHeuristics() d
Enhance calcColdCallHeuristics for InvokeInst
Summary: When identifying cold blocks, consider only the edge to the normal destination if the terminator is InvokeInst and let calcInvokeHeuristics() decide edge weights for the InvokeInst.
Reviewers: mcrosier, hfinkel, davidxl
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D24868
llvm-svn: 282262
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Revision tags: llvmorg-3.9.0, llvmorg-3.9.0-rc3, llvmorg-3.9.0-rc2, llvmorg-3.9.0-rc1 |
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aa3506c5 |
| 28-Jul-2016 |
Adam Nemet <[email protected]> |
[BPI] Add new LazyBPI analysis
Summary: The motivation is the same as in D22141: In order to add the hotness attribute to optimization remarks we need BFI to be available in all passes that emit opt
[BPI] Add new LazyBPI analysis
Summary: The motivation is the same as in D22141: In order to add the hotness attribute to optimization remarks we need BFI to be available in all passes that emit optimization remarks. BFI depends on BPI so unless we make this lazy as well we would still compute BPI unconditionally.
The solution is to use the new LazyBPI pass in LazyBFI and only compute BPI when computation of BFI is requested by the client.
I extended the laziness test using a LoopDistribute test to also cover BPI.
Reviewers: hfinkel, davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D22835
llvm-svn: 277083
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Revision tags: llvmorg-3.8.1, llvmorg-3.8.1-rc1 |
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6e5dd414 |
| 05-May-2016 |
Xinliang David Li <[email protected]> |
[PM] Port Branch Probability Analysis pass to the new pass manager.
Differential Revision: http://reviews.llvm.org/D19839
llvm-svn: 268601
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Revision tags: llvmorg-3.8.0, llvmorg-3.8.0-rc3, llvmorg-3.8.0-rc2, llvmorg-3.8.0-rc1, llvmorg-3.7.1, llvmorg-3.7.1-rc2, llvmorg-3.7.1-rc1 |
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15ea0163 |
| 25-Sep-2015 |
Cong Hou <[email protected]> |
Use fixed-point representation for BranchProbability.
BranchProbability now is represented by its numerator and denominator in uint32_t type. This patch changes this representation into a fixed poin
Use fixed-point representation for BranchProbability.
BranchProbability now is represented by its numerator and denominator in uint32_t type. This patch changes this representation into a fixed point that is represented by the numerator in uint32_t type and a constant denominator 1<<31. This is quite similar to the representation of BlockMass in BlockFrequencyInfoImpl.h. There are several pros and cons of this change:
Pros:
1. It uses only a half space of the current one. 2. Some operations are much faster like plus, subtraction, comparison, and scaling by an integer.
Cons:
1. Constructing a probability using arbitrary numerator and denominator needs additional calculations. 2. It is a little less precise than before as we use a fixed denominator. For example, 1 - 1/3 may not be exactly identical to 1 / 3 (this will lead to many BranchProbability unit test failures). This should not matter when we only use it for branch probability. If we use it like a rational value for some precise calculations we may need another construct like ValueRatio.
One important reason for this change is that we propose to store branch probabilities instead of edge weights in MachineBasicBlock. We also want clients to use probability instead of weight when adding successors to a MBB. The current BranchProbability has more space which may be a concern.
Differential revision: http://reviews.llvm.org/D12603
llvm-svn: 248633
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Revision tags: llvmorg-3.7.0, llvmorg-3.7.0-rc4, llvmorg-3.7.0-rc3, llvmorg-3.7.0-rc2, llvmorg-3.7.0-rc1, llvmorg-3.6.2, llvmorg-3.6.2-rc1, llvmorg-3.6.1, llvmorg-3.6.1-rc1 |
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a73f3d51 |
| 15-Apr-2015 |
Daniel Jasper <[email protected]> |
Re-apply r234898 and fix tests.
This commit makes LLVM not estimate branch probabilities when doing a single bit bitmask tests.
The code that originally made me discover this is:
if ((a & 0x1) =
Re-apply r234898 and fix tests.
This commit makes LLVM not estimate branch probabilities when doing a single bit bitmask tests.
The code that originally made me discover this is:
if ((a & 0x1) == 0x1) { .. }
In this case we don't actually have any branch probability information and should not assume to have any. LLVM transforms this into:
%and = and i32 %a, 1 %tobool = icmp eq i32 %and, 0
So, in this case, the result of a bitwise and is compared against 0, but nevertheless, we should not assume to have probability information.
CodeGen/ARM/2013-10-11-select-stalls.ll started failing because the changed probabilities changed the results of ARMBaseInstrInfo::isProfitableToIfCvt() and led to an Ifcvt of the diamond in the test. AFAICT, the test was never meant to test this and thus changing the test input slightly to not change the probabilities seems like the best way to preserve the meaning of the test.
llvm-svn: 234979
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2defea0e |
| 14-Apr-2015 |
Rafael Espindola <[email protected]> |
Revert "The code that originally made me discover this is:"
This reverts commit r234898. CodeGen/ARM/2013-10-11-select-stalls.ll was faling.
llvm-svn: 234903
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8229ebb9 |
| 14-Apr-2015 |
Daniel Jasper <[email protected]> |
The code that originally made me discover this is:
if ((a & 0x1) == 0x1) { .. }
In this case we don't actually have any branch probability information and should not assume to have any. LLV
The code that originally made me discover this is:
if ((a & 0x1) == 0x1) { .. }
In this case we don't actually have any branch probability information and should not assume to have any. LLVM transforms this into:
%and = and i32 %a, 1 %tobool = icmp eq i32 %and, 0
So, in this case, the result of a bitwise and is compared against 0, but nevertheless, we should not assume to have probability information.
llvm-svn: 234898
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Revision tags: llvmorg-3.5.2, llvmorg-3.5.2-rc1 |
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a79ac14f |
| 27-Feb-2015 |
David Blaikie <[email protected]> |
[opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.
A similar migration script can be used to update test
[opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.
A similar migration script can be used to update test cases, though a few more test case improvements/changes were required this time around: (r229269-r229278)
import fileinput import sys import re
pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")
for line in sys.stdin: sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))
Reviewers: rafael, dexonsmith, grosser
Differential Revision: http://reviews.llvm.org/D7649
llvm-svn: 230794
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