Teach SCCP to create notconstant lattice values from inequality
assumes and nonnull metadata, and update getConstant() to make
use of them. Additionally isOverdefined() needs to be changed to
consider notconstant an overdefined value.
Handling inequality branches is delayed until our branch on undef
story in other passes has been improved.
Differential Revision: https://reviews.llvm.org/D83643
If an analysis is actually invalidated, there's already a log statement
for that: 'Invalidating analysis: FooAnalysis'.
Otherwise the statement is not very useful.
Reviewed By: asbirlea, ychen
Differential Revision: https://reviews.llvm.org/D84981
Determine whether switch edges are feasible based on range information,
and remove non-feasible edges lateron.
This does not try to determine whether the default edge is dead,
as we'd have to determine that the range is fully covered by the
cases for that.
Another limitation here is that we don't remove dead cases that
have the same successor as a live case. I'm not handling this
because I wanted to keep the edge removal based on feasible edges
only, rather than inspecting ranges again there -- this does not
seem like a particularly useful case to handle.
Differential Revision: https://reviews.llvm.org/D84270
Problem:
Right now, our "Running pass" is not accurate when passes are wrapped in adaptor because adaptor is never skipped and a pass could be skipped. The other problem is that "Running pass" for a adaptor is before any "Running pass" of passes/analyses it depends on. (for example, FunctionToLoopPassAdaptor). So the order of printing is not the actual order.
Solution:
Doing things like PassManager::Debuglogging is very intrusive because we need to specify Debuglogging whenever adaptor is created. (Actually, right now we're not specifying Debuglogging for some sub-PassManagers. Check PassBuilder)
This patch move debug logging for pass as a PassInstrument callback. We could be sure that all running passes are logged and in the correct order.
This could also be used to implement hierarchy pass logging in legacy PM. We could also move logging of pass manager to this if we want.
The test fixes looks messy. It includes changes:
- Remove PassInstrumentationAnalysis
- Remove PassAdaptor
- If a PassAdaptor is for a real pass, the pass is added
- Pass reorder (to the correct order), related to PassAdaptor
- Add missing passes (due to Debuglogging not passed down)
Reviewed By: asbirlea, aeubanks
Differential Revision: https://reviews.llvm.org/D84774
As far as I know, ipconstprop has not been used in years and ipsccp has
been used instead. This has the potential for confusion and sometimes
leads people to spend time finding & reporting bugs as well as
updating it to work with the latest API changes.
This patch moves the tests over to SCCP. There's one functional difference
I am aware of: ipconstprop propagates for each call-site individually, so
for functions that are called with different constant arguments it can sometimes
produce better results than ipsccp (at much higher compile-time cost).But
IPSCCP can be thought to do so as well for internal functions and as mentioned
earlier, the pass seems unused in practice (and there are no plans on working
towards enabling it anytime).
Also discussed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2020-July/143773.html
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D84447
Reapply with DTU update moved after CFG update, which is a
requirement of the API.
-----
Non-feasible control-flow edges are currently removed by replacing
the branch condition with a constant and then calling
ConstantFoldTerminator. This happens in a rather roundabout manner,
by inspecting the users (effectively: predecessors) of unreachable
blocks, and further complicated by the need to explicitly materialize
the condition for "forced" edges. I would like to extend SCCP to
discard switch conditions that are non-feasible based on range
information, but this is incompatible with the current approach
(as there is no single constant we could use.)
Instead, this patch explicitly removes non-feasible edges. It
currently only needs to handle the case where there is a single
feasible edge. The llvm_unreachable() branch will need to be
implemented for the aforementioned switch improvement.
Differential Revision: https://reviews.llvm.org/D84264
This patch updates IPSCCP to drop argmemonly and
inaccessiblemem_or_argmemonly if it replaces a pointer argument.
Fixes PR46717.
Reviewers: efriedma, davide, nikic, jdoerfert
Reviewed By: efriedma, jdoerfert
Differential Revision: https://reviews.llvm.org/D84432
It breaks stage-2 build. Clang crashed when compiling
llvm/lib/Target/Hexagon/HexagonFrameLowering.cpp
llvm/Support/GenericDomTree.h eraseNode: Node is not a leaf node
Non-feasible control-flow edges are currently removed by replacing
the branch condition with a constant and then calling
ConstantFoldTerminator. This happens in a rather roundabout manner,
by inspecting the users (effectively: predecessors) of unreachable
blocks, and further complicated by the need to explicitly materialize
the condition for "forced" edges. I would like to extend SCCP to
discard switch conditions that are non-feasible based on range
information, but this is incompatible with the current approach
(as there is no single constant we could use.)
Instead, this patch explicitly removes non-feasible edges. It
currently only needs to handle the case where there is a single
feasible edge. The llvm_unreachable() branch will need to be
implemented for the aforementioned switch improvement.
Differential Revision: https://reviews.llvm.org/D84264
As long as RenamedOp is not guaranteed to be accurate, we cannot
assert here and should just return false. This was already done
for the other conditions in this function.
Fixes https://bugs.llvm.org/show_bug.cgi?id=46814.
And adjust the indbrtest4 test to actually test what it's supposed
to. BB1 is supposed to be eliminated here, but isn't, because
BB0 still branches to it. This was lost due to the incomplete CHECK
lines.
If we inferred a range for the function return value, we can add !range
at all call-sites of the function, if the range does not include undef.
Reviewers: efriedma, davide, nikic
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D83952
Both users of predicteinfo (NewGVN and SCCP) are interested in
getting a cmp constraint on the predicated value. They currently
implement separate logic for this. This patch adds a common method
for this in PredicateBase.
This enables a missing bit of PredicateInfo handling in SCCP: Now
the predicate on the condition itself is also used. For switches
it means we know that the switched-on value is the same as the case
value. For assumes/branches we know that the condition is true or
false.
Differential Revision: https://reviews.llvm.org/D83640
Some of the tests in the llvm/test/Transforms/IPConstantProp directory
actually only use -ipsccp. Those tests belong to the other (IP)SCCP
tests in llvm/test/Transforms/SCCP/ and this commits moves them there to
avoid confusion with IPConstantProp.
Currently SCCP does not combine the information of conditions joined by
AND in the true branch or OR in the false branch.
For branches on AND, 2 copies will be inserted for the true branch, with
one being the operand of the other as in the code below. We can combine
the information using intersection. Note that for the OR case, the
copies are inserted in the false branch, where using intersection is
safe as well.
define void @foo(i32 %a) {
entry:
%lt = icmp ult i32 %a, 100
%gt = icmp ugt i32 %a, 20
%and = and i1 %lt, %gt
; Has predicate info
; branch predicate info { TrueEdge: 1 Comparison: %lt = icmp ult i32 %a, 100 Edge: [label %entry,label %true] }
%a.0 = call i32 @llvm.ssa.copy.140247425954880(i32 %a)
; Has predicate info
; branch predicate info { TrueEdge: 1 Comparison: %gt = icmp ugt i32 %a, 20 Edge: [label %entry,label %false] }
%a.1 = call i32 @llvm.ssa.copy.140247425954880(i32 %a.0)
br i1 %and, label %true, label %false
true: ; preds = %entry
call void @use(i32 %a.1)
%true.1 = icmp ne i32 %a.1, 20
call void @use.i1(i1 %true.1)
ret void
false: ; preds = %entry
call void @use(i32 %a.1)
ret void
}
Reviewers: efriedma, davide, mssimpso, nikic
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D77808
When all else fails, use range metadata to constrain the result
of loads and calls. It should also be possible to use !nonnull,
but that would require some general support for inequalities in
SCCP first.
Differential Revision: https://reviews.llvm.org/D83179
Take assume predicates into account when visiting ssa.copy. The
handling is the same as for branch predicates, with the difference
that we're always on the true edge.
Differential Revision: https://reviews.llvm.org/D83257
This patch updates SCCP/IPSCCP to use the computed range info to turn
sexts into zexts, if the value is known to be non-negative. We already
to a similar transform in CorrelatedValuePropagation, but it seems like
we can catch a lot of additional cases by doing it in SCCP/IPSCCP as
well.
The transform is limited to ranges that are known to not include undef.
Currently constant ranges from conditions are treated as potentially
containing undef, due to PR46144. Once we flip this, the transform will
be more effective in practice.
Reviewers: efriedma, davide
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D81756
Currently SCCP does not widen PHIs, stores or along call edges
(arguments/return values), but on operations that directly extend ranges
(like binary operators).
This means PHIs, stores and call edges are not pessimized by widening
currently, while binary operators are. The main reason for widening
operators initially was that opting-out for certain operations was
more straight-forward in the initial implementation (and it did not
matter too much, as range support initially was only implemented for a
very limited set of operations.
During the discussion in D78391, it was suggested to consider flipping
widening to PHIs, stores and along call edges. After adding support for
tracking the number of range extensions in ValueLattice, limiting the
number of range extensions per value is straight forward.
This patch introduces a MaxWidenSteps option to the MergeOptions,
limiting the number of range extensions per value. For PHIs, it seems
natural allow an extension for each (active) incoming value plus 1. For
the other cases, a arbitrary limit of 10 has been chosen initially. It would
potentially make sense to set it depending on the users of a
function/global, but that still needs investigating. This potentially
leads to more state-changes and longer compile-times.
The results look quite promising (MultiSource, SPEC):
Same hash: 179 (filtered out)
Remaining: 58
Metric: sccp.IPNumInstRemoved
Program base widen-phi diff
test-suite...ks/Prolangs-C/agrep/agrep.test 58.00 82.00 41.4%
test-suite...marks/SciMark2-C/scimark2.test 32.00 43.00 34.4%
test-suite...rks/FreeBench/mason/mason.test 6.00 8.00 33.3%
test-suite...langs-C/football/football.test 104.00 128.00 23.1%
test-suite...cations/hexxagon/hexxagon.test 36.00 42.00 16.7%
test-suite...CFP2000/177.mesa/177.mesa.test 214.00 249.00 16.4%
test-suite...ngs-C/assembler/assembler.test 14.00 16.00 14.3%
test-suite...arks/VersaBench/dbms/dbms.test 10.00 11.00 10.0%
test-suite...oxyApps-C++/miniFE/miniFE.test 43.00 47.00 9.3%
test-suite...ications/JM/ldecod/ldecod.test 179.00 195.00 8.9%
test-suite...CFP2006/433.milc/433.milc.test 249.00 265.00 6.4%
test-suite.../CINT2000/175.vpr/175.vpr.test 98.00 104.00 6.1%
test-suite...peg2/mpeg2dec/mpeg2decode.test 70.00 74.00 5.7%
test-suite...CFP2000/188.ammp/188.ammp.test 71.00 75.00 5.6%
test-suite...ce/Benchmarks/PAQ8p/paq8p.test 111.00 117.00 5.4%
test-suite...ce/Applications/Burg/burg.test 41.00 43.00 4.9%
test-suite...000/197.parser/197.parser.test 66.00 69.00 4.5%
test-suite...tions/lambda-0.1.3/lambda.test 23.00 24.00 4.3%
test-suite...urce/Applications/lua/lua.test 301.00 313.00 4.0%
test-suite...TimberWolfMC/timberwolfmc.test 76.00 79.00 3.9%
test-suite...lications/ClamAV/clamscan.test 991.00 1030.00 3.9%
test-suite...plications/d/make_dparser.test 53.00 55.00 3.8%
test-suite...fice-ispell/office-ispell.test 83.00 86.00 3.6%
test-suite...lications/obsequi/Obsequi.test 28.00 29.00 3.6%
test-suite.../Prolangs-C/bison/mybison.test 56.00 58.00 3.6%
test-suite.../CINT2000/254.gap/254.gap.test 170.00 176.00 3.5%
test-suite.../Applications/lemon/lemon.test 30.00 31.00 3.3%
test-suite.../CINT2000/176.gcc/176.gcc.test 1202.00 1240.00 3.2%
test-suite...pplications/treecc/treecc.test 79.00 81.00 2.5%
test-suite...chmarks/MallocBench/gs/gs.test 357.00 366.00 2.5%
test-suite...eeBench/analyzer/analyzer.test 103.00 105.00 1.9%
test-suite...T2006/445.gobmk/445.gobmk.test 1697.00 1724.00 1.6%
test-suite...006/453.povray/453.povray.test 1812.00 1839.00 1.5%
test-suite.../Benchmarks/Bullet/bullet.test 337.00 342.00 1.5%
test-suite.../CINT2000/252.eon/252.eon.test 426.00 432.00 1.4%
test-suite...T2000/300.twolf/300.twolf.test 214.00 217.00 1.4%
test-suite...pplications/oggenc/oggenc.test 244.00 247.00 1.2%
test-suite.../CINT2006/403.gcc/403.gcc.test 4008.00 4055.00 1.2%
test-suite...T2006/456.hmmer/456.hmmer.test 175.00 177.00 1.1%
test-suite...nal/skidmarks10/skidmarks.test 430.00 434.00 0.9%
test-suite.../Applications/sgefa/sgefa.test 115.00 116.00 0.9%
test-suite...006/447.dealII/447.dealII.test 1082.00 1091.00 0.8%
test-suite...6/482.sphinx3/482.sphinx3.test 141.00 142.00 0.7%
test-suite...ocBench/espresso/espresso.test 152.00 153.00 0.7%
test-suite...3.xalancbmk/483.xalancbmk.test 4003.00 4025.00 0.5%
test-suite...lications/sqlite3/sqlite3.test 548.00 551.00 0.5%
test-suite...marks/7zip/7zip-benchmark.test 5522.00 5551.00 0.5%
test-suite...nsumer-lame/consumer-lame.test 208.00 209.00 0.5%
test-suite...:: External/Povray/povray.test 1556.00 1563.00 0.4%
test-suite...000/186.crafty/186.crafty.test 298.00 299.00 0.3%
test-suite.../Applications/SPASS/SPASS.test 2019.00 2025.00 0.3%
test-suite...ications/JM/lencod/lencod.test 8427.00 8449.00 0.3%
test-suite...6/464.h264ref/464.h264ref.test 6797.00 6813.00 0.2%
test-suite...6/471.omnetpp/471.omnetpp.test 431.00 430.00 -0.2%
test-suite...006/450.soplex/450.soplex.test 446.00 447.00 0.2%
test-suite...0.perlbench/400.perlbench.test 1729.00 1727.00 -0.1%
test-suite...000/255.vortex/255.vortex.test 3815.00 3819.00 0.1%
Reviewers: efriedma, nikic, davide
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D79036
For IR generated by a compiler, this is really simple: you just take the
datalayout from the beginning of the file, and apply it to all the IR
later in the file. For optimization testcases that don't care about the
datalayout, this is also really simple: we just use the default
datalayout.
The complexity here comes from the fact that some LLVM tools allow
overriding the datalayout: some tools have an explicit flag for this,
some tools will infer a datalayout based on the code generation target.
Supporting this properly required plumbing through a bunch of new
machinery: we want to allow overriding the datalayout after the
datalayout is parsed from the file, but before we use any information
from it. Therefore, IR/bitcode parsing now has a callback to allow tools
to compute the datalayout at the appropriate time.
Not sure if I covered all the LLVM tools that want to use the callback.
(clang? lli? Misc IR manipulation tools like llvm-link?). But this is at
least enough for all the LLVM regression tests, and IR without a
datalayout is not something frontends should generate.
This change had some sort of weird effects for certain CodeGen
regression tests: if the datalayout is overridden with a datalayout with
a different program or stack address space, we now parse IR based on the
overridden datalayout, instead of the one written in the file (or the
default one, if none is specified). This broke a few AVR tests, and one
AMDGPU test.
Outside the CodeGen tests I mentioned, the test changes are all just
fixing CHECK lines and moving around datalayout lines in weird places.
Differential Revision: https://reviews.llvm.org/D78403
Summary: Currenlty BPI unconditionally creates post dominator tree each time. While this is not incorrect we can save compile time by reusing existing post dominator tree (when it's valid) provided by analysis manager.
Reviewers: skatkov, taewookoh, yrouban
Reviewed By: skatkov
Subscribers: hiraditya, steven_wu, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D78987
Integer ranges can be used for loaded/stored values. Note that widening
can be disabled for loads/stores, as we only rely on instructions that
cause continued increases to ranges to be widened (like binary
operators).
Reviewers: efriedma, mssimpso, davide
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D78433
Currently an unknown/undef value is marked as overdefined when merged
with an empty range. An empty range can occur in unreachable/dead code.
When merging the new unknown state (= no value known yet) with an empty
range, there still isn't any information about the value yet and we can
stay in unknown.
This gives a few nice improvements on the number of instructions removed
by IPSCCP:
Same hash: 170 (filtered out)
Remaining: 67
Metric: sccp.IPNumInstRemoved
Program base patch diff
test-suite...rks/FreeBench/mason/mason.test 3.00 6.00 100.0%
test-suite...nchmarks/McCat/18-imp/imp.test 3.00 5.00 66.7%
test-suite...C/CFP2000/179.art/179.art.test 2.00 3.00 50.0%
test-suite...ijndael/security-rijndael.test 2.00 3.00 50.0%
test-suite...ks/Prolangs-C/agrep/agrep.test 40.00 58.00 45.0%
test-suite...ce/Applications/Burg/burg.test 26.00 37.00 42.3%
test-suite...cCat/03-testtrie/testtrie.test 3.00 4.00 33.3%
test-suite...Source/Benchmarks/sim/sim.test 29.00 36.00 24.1%
test-suite.../Applications/spiff/spiff.test 9.00 11.00 22.2%
test-suite...s/FreeBench/neural/neural.test 5.00 6.00 20.0%
test-suite...pplications/treecc/treecc.test 66.00 79.00 19.7%
test-suite...langs-C/football/football.test 85.00 101.00 18.8%
test-suite...ce/Benchmarks/PAQ8p/paq8p.test 90.00 105.00 16.7%
test-suite...oxyApps-C++/miniFE/miniFE.test 37.00 43.00 16.2%
test-suite...rks/FreeBench/pifft/pifft.test 26.00 30.00 15.4%
test-suite...lications/sqlite3/sqlite3.test 481.00 548.00 13.9%
test-suite...marks/7zip/7zip-benchmark.test 4875.00 5522.00 13.3%
test-suite.../CINT2000/176.gcc/176.gcc.test 1117.00 1197.00 7.2%
test-suite...0.perlbench/400.perlbench.test 1618.00 1732.00 7.0%
Reviewers: efriedma, nikic, davide
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D78667
visitExtractValueInst uses mergeInValue, so it already can handle
constant ranges. Initially the early exit was using isOverdefined to
keep things as NFC during the initial move to ValueLatticeElement.
As the function already supports constant ranges, it can just use
ValueState[&I].isOverdefined.
Reviewers: efriedma, mssimpso, davide
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D78393
For non-integer constants/expressions and overdefined, I think we can
just use SimplifyBinOp to do common folds. By just passing a context
with the DL, SimplifyBinOp should not try to get additional information
from looking at definitions.
For overdefined values, it should be enough to just pass the original
operand.
Note: The comment before the `if (isconstant(V1State)...` was wrong
originally: isConstant() also matches integer ranges with a single
element. It is correct now.
Reviewers: efriedma, davide, mssimpso, aartbik
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D76459
Nikita Popov