History log of /llvm-project-15.0.7/llvm/test/Analysis/BranchProbabilityInfo/basic.ll (Results 1 – 25 of 31)
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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
# 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
# 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.


# 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
# 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


# 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
# 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
# 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
# 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
# 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
# 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


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
# 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
# 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


# 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

show more ...


Revision tags: llvmorg-3.5.2, llvmorg-3.5.2-rc1
# 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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