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
Let separate-const-offset-from-gep pass handle trunc() when it calculates
constant offset relative to base. The pass itself may insert trunc()
instructions when it canonicalises array indices to pointer-size integers
and needs to handle trunc() in order to evaluate the offset.
Differential Revision: https://reviews.llvm.org/D46732
llvm-svn: 332142
Phi nodes can reside in live blocks but one of their incoming
arguments can come from a dead block. Dead blocks and reassociate
don't play nice together. In fact, reassociate performs an RPO
as a first step to avoid processing dead blocks.
The reason why Reassociate might not fixpoint when examining
dead blocks is that the following:
%xor0 = xor i16 %xor1, undef
%xor1 = xor i16 %xor0, undef
is perfectly valid LLVM IR (if it appears in a dead block),
so the worklist algorithm keeps pushing the two instructions for
reexamination. Note that this is not Reassociate fault, at least
not entirely. It's llvm that has a weird definition of dominance.
Fixes PR37390.
llvm-svn: 332100
This commit adds a wrapper for std::distance() which works with ranges.
As it would be a common case to write `distance(predecessors(BB))`, this
also introduces `pred_size()` and `succ_size()` helpers to make that
easier to write.
Differential Revision: https://reviews.llvm.org/D46668
llvm-svn: 332057
Summary:
This change teaches DSE that the atomic memory intrinsics can be overwriten
partially in the same way as the non-atomic forms. Specifically, that the
atomic memcpy & memset can be shortened at the end and that the atomic memset
can be shortened at the beginning, if they partially overwritten
by later stores.
Reviewers: mkazantsev, skatkov, apilipenko, efriedma, rsmith, spatel, filcab, sanjoy
Reviewed By: efriedma
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45584
llvm-svn: 331991
Summary:
MergedLoadStoreMotion::mergeStores is using some heuristics
to limit the amount of stores that it tries to sink (see
MagicCompileTimeControl in MergedLoadStoreMotion.cpp). The
heuristic involves counting the number of instructions in
one of the basic blocks that is part of the transformation.
We now ignore dbg intrinsics when counting instruction for
the MagicCompileTimeControl heuristic. This to make sure that
the amount of stores that are sunk doesn't depend on the amount
of debug information (if -g is used or not).
Reviewers: Gerolf, davide, majnemer
Reviewed By: davide
Subscribers: dberlin, bjope, aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D46600
llvm-svn: 331852
Computing this property within the existing walk ensures that the cost is linear with the size of the block. If we did this from within isGuaranteedToExecute, it would be quadratic without some very fancy caching.
This allows us to reliably catch a hoistable instruction within a header which may throw at some point *after* our hoistable instruction. It doesn't do anything for non-header cases, but given how common single block loops are, this seems very worthwhile.
llvm-svn: 331557
Two of these are immediately dereferenced on the next line. The other two are passed immediately to the IRBuilder constructor which can't handle a nullptr.
llvm-svn: 331500
These are casts on users of a PHINode to Instruction. I think since PHINode is an Instruction any users would also be Instructions. At least a cast will give us an assertion if its wrong.
llvm-svn: 331498
Summary:
Some of our internal testing detected a major compile time regression which I've
tracked down to:
r278938 - Revert "Reassociate: Reprocess RedoInsts after each inst".
It appears that processing long chains of reassociatable instructions causes
non-linear (potentially exponential) growth in the number of times an
instruction is revisited. For example, the included test revisits instructions
220 times in a 20-instruction test.
It appears that r278938 reversed the order instructions were visited and that
this is preventing scheduled revisits from being cancelled as a result of
visiting the instructions naturally during normal processing. However, simply
reversing the order also harmed the generated code. Upon closer inspection, it
was discovered that revisits occurred in the opposite order to the first pass
(Thanks to escha for spotting that).
This patch makes the revisit order consistent with the first pass which allows
more revisits to be cancelled. This does appear to have a small impact on the
generated code in few cases but it significantly reduces compile-time.
After this patch, our internal test that was most affected by the regression
dropped from ~2 million revisits to ~4k resulting in Reassociate having 0.46%
of the runtime it had before (99.54% improvement).
Here's the summaries reported by lnt for the LLVM test-suite with --benchmarking-only:
| metric | geomean before patch | geomean after patch | delta |
| ----- | ----- | ----- | ----- |
| compile time | 0.1956 | 0.1261 | -35.54% |
| execution time | 0.3240 | 0.3237 | - |
| code size | 7365.4459 | 7365.6079 | - |
The results have a few wins and losses on compile-time, mostly in the +/- 2.5% range. There was one outlier though:
| Performance Regressions - compile_time | Δ | Previous | Current |
| MultiSource/Benchmarks/ASC_Sequoia/CrystalMk/CrystalMk | 9.82% | 2.0473 | 2.2483 |
Reviewers: javed.absar, dberlin
Reviewed By: dberlin
Subscribers: kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D45734
llvm-svn: 331381
This is a follow-up to r331272.
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
https://reviews.llvm.org/D46290
llvm-svn: 331275
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
phi is on lhs of a comparison op.
For the following testcase,
L1:
%t0 = add i32 %m, 7
%t3 = icmp eq i32* %t2, null
br i1 %t3, label %L3, label %L2
L2:
%t4 = load i32, i32* %t2, align 4
br label %L3
L3:
%t5 = phi i32 [ %t0, %L1 ], [ %t4, %L2 ]
%t6 = icmp eq i32 %t0, %t5
br i1 %t6, label %L4, label %L5
We know if we go through the path L1 --> L3, %t6 should always be true. However
currently, if the rhs of the eq comparison is phi, JumpThreading fails to
evaluate %t6 to true. And we know that Instcombine cannot guarantee always
canonicalizing phi to the left hand side of the comparison operation according
to the operand priority comparison mechanism in instcombine. The patch handles
the case when rhs of the comparison op is a phi.
Differential Revision: https://reviews.llvm.org/D46275
llvm-svn: 331266
unswitch and replace it with the amazingly simple update API code.
This addresses piles of FIXMEs around the update logic here and makes
everything substantially simpler.
llvm-svn: 331247
code review.
It turns out this *is* necessary, and I read the comment on the API
correctly the first time. ;]
The `applyUpdates` routine requires that updates are "balanced". This is
in order to cleanly handle cycles like inserting, removing, nad then
re-inserting the same edge. This precludes inserting the same edge
multiple times in a row as handling that would cause the insertion logic
to become *ordered* instead of *unordered* (which is what the API
provides).
It happens that in this specific case nothing (other than an assert and
contract violation) goes wrong because we're never inserting and
removing the same edge. The implementation *happens* to do the right
thing to eliminate redundant insertions in that case.
But the requirement is there and there is an assert to catch it.
Somehow, after the code review I never did another asserts-clang build
testing loop-unswich for a long time. As a consequence, I didn't notice
this despite a bunch of testing going on, but it shows up immediately
with an asserts build of clang itself.
llvm-svn: 331246
See r331124 for how I made a list of files missing the include.
I then ran this Python script:
for f in open('filelist.txt'):
f = f.strip()
fl = open(f).readlines()
found = False
for i in xrange(len(fl)):
p = '#include "llvm/'
if not fl[i].startswith(p):
continue
if fl[i][len(p):] > 'Config':
fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
found = True
break
if not found:
print 'not found', f
else:
open(f, 'w').write(''.join(fl))
and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.
No intended behavior change.
llvm-svn: 331184
The effect of doing so is not disrupting the LoopPassManager when mixing this pass with other loop passes. This should help locality of access substaintially and avoids the cost of computing PostDom.
The assumption here is that the full GuardWidening (which does use PostDom) is run as a canonicalization before loop opts and that this version is just catching cases exposed by other loop passes. (i.e. LoopPredication, IndVarSimplify, LoopUnswitch, etc..)
llvm-svn: 331094
The idea is to have a pass which performs the same transformation as GuardWidening, but can be run within a loop pass manager without disrupting the pass manager structure. As demonstrated by the test case, this doesn't quite get there because of issues with post dom, but it gives a good step in the right direction. the motivation is purely to reduce compile time since we can now preserve locality during the loop walk.
This patch only includes a legacy pass. A follow up will add a new style pass as well.
llvm-svn: 331060
We currently support LCSSA PHI nodes in the outer loop exit, if their
incoming values do not come from the outer loop latch or if the
outer loop latch has a single predecessor. In that case, the outer loop latch
will be executed only if the inner loop gets executed. If we have multiple
predecessors for the outer loop latch, it may be executed even if the inner
loop does not get executed.
This is a first step to support the case described in
https://bugs.llvm.org/show_bug.cgi?id=30472
Reviewers: efriedma, karthikthecool, mcrosier
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D43237
llvm-svn: 331037
This also means we have to check if the latch is the exiting block now,
as `transform` expects the latches to be the exiting blocks too.
https://bugs.llvm.org/show_bug.cgi?id=36586
Reviewers: efriedma, davide, karthikthecool
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D45279
llvm-svn: 330806
Summary:
When Reassociate is rewriting an expression tree it may
reuse old binary expression nodes, for new expressions.
Whenever an expression node is reused, but with a non-trivial
change in the result, we need to invalidate any debug info
that is associated with the node.
If for example rewriting
x = mul a, b
y = mul c, x
into
x = mul c, b
y = mul a, x
we still get the same result for 'y', but 'x' is a new expression.
All debug info referring to 'x' must be invalidated (marked as
optimized out) since we no longer calculate the expected value.
As a side-effect this patch avoid (at least some) problems where
reassociate could end up creating IR with debug-use before def.
Earlier the dbg.value nodes where left untouched in the IR, while
the reused binary nodes where sinked to just before the root node
of the rewritten expression tree. See PR27273 for more info about
such problems.
Reviewers: dblaikie, aprantl, dexonsmith
Reviewed By: aprantl
Subscribers: JDevlieghere, llvm-commits
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D45975
llvm-svn: 330804
Summary:
Use a MapVector instead of a DenseMap for RemMap since it is iteratated
over and the order of iteration can effect the order that new
instructions are created. This can in turn effect the use list order of
div/rem input values if multiple new instructions are created that share
any input values.
Reviewers: spatel
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D45858
llvm-svn: 330792
update API for dominators rather than doing manual, hacky updates.
This is just the first step, but in some ways the most important as it
moves the non-trivial unswitching to update the domtree rather than
fully recalculating it each time.
Subsequent patches should remove the custom update logic used by the
trivial unswitch and replace it with uses of the update API.
This also fixes a number of bugs I was seeing when testing non-trivial
unswitch due to it querying the quasi-correct dominator tree. Now the
tree is 100% correct and safe to query. That said, there are still more
bugs I can see with non-trivial unswitch just running over the test
suite, so more bugfix patches are needed as well.
Thanks to both Sanjoy and Fedor for reviews and testing!
Differential Revision: https://reviews.llvm.org/D45943
llvm-svn: 330787
After D43236, we started interchanging loops with empty dependence
matrices. In isProfitableForVectorization, we try to determine if
interchanging makes the loop dependences more friendly to the
vectorizer. If there are no dependences, we should not interchange,
based on that heuristic.
Reviewers: efriedma, mcrosier, karthikthecool, blitz.opensource
Reviewed By: mcrosier
Differential Revision: https://reviews.llvm.org/D45208
llvm-svn: 330738
loop unswitch.
This code incorrectly added the header to the loop block set early. As
a consequence we would incorrectly conclude that a nested loop body had
already been visited when the header of the outer loop was the preheader
of the nested loop. In retrospect, adding the header eagerly doesn't
really make sense. It seems nicer to let the cycle be formed naturally.
This will catch crazy bugs in the CFG reconstruction where we can't
correctly form the cycle earlier rather than later, and makes the rest
of the logic just fall out.
I've also added various asserts that make these issues *much* easier to
debug.
llvm-svn: 330707
This code path can very clearly be called in a context where we have
baselined all the cloned blocks to a particular loop and are trying to
handle nested subloops. There is no harm in this, so just relax the
assert. I've added a test case that will make sure we actually exercise
this code path.
llvm-svn: 330680
(notionally Scalar.h is part of libLLVMScalarOpts, so it shouldn't be
included by InstCombine which doesn't/shouldn't need to depend on
ScalarOpts)
llvm-svn: 330669
If a loop with child loops becomes our new inner loop after
interchanging, we only need to update LoopInfo for the blocks defined in
the old outer loop. BBs in child loops will stay there.
Reviewers: efriedma, karthikthecool, mcrosier
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D45970
llvm-svn: 330653
Summary: We do not need nonull attribute if we know an argument is going to be constant.
Reviewers: junbuml, davide, fhahn
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45608
llvm-svn: 330641
Summary:
Skip basic blocks not reachable from the entry node
in MemCpyOptPass::iterateOnFunction.
Code that is unreachable may have properties that do not exist
for reachable code (an instruction in a basic block can for
example be dominated by a later instruction in the same basic
block, for example if there is a single block loop).
MemCpyOptPass::processStore is only safe to use for reachable
basic blocks, since it may iterate past the basic block
beginning when used for unreachable blocks. By simply skipping
to optimize unreachable basic blocks we can avoid asserts such
as "Assertion `!NodePtr->isKnownSentinel()' failed."
in MemCpyOptPass::processStore.
The problem was detected by fuzz tests.
Reviewers: eli.friedman, dneilson, efriedma
Reviewed By: efriedma
Subscribers: efriedma, llvm-commits
Differential Revision: https://reviews.llvm.org/D45889
llvm-svn: 330635
Summary:
This change teaches DSE that the atomic memory intrinsics are stores
that can be eliminated, and can allow other stores to be eliminated.
This change specifically does not teach DSE that these intrinsics
can be partially eliminated (i.e. length reduced, and dest/src changed);
that will be handled in another change.
Reviewers: mkazantsev, skatkov, apilipenko, efriedma, rsmith
Reviewed By: efriedma
Subscribers: dmgreen, llvm-commits
Differential Revision: https://reviews.llvm.org/D45535
llvm-svn: 330629
The condition this was asserting doesn't actually hold. I've added
comments to explain why, removed the assert, and added a fun test case
reduced out of 403.gcc.
llvm-svn: 330564
It also adds a check making sure PHIs for operands are all in the same
block.
Patch by Daniel Berlin <dberlin@dberlin.org>
Reviewers: dberlin, davide
Differential Revision: https://reviews.llvm.org/D43865
llvm-svn: 330444
Reapply the patches with a fix. Thanks Ilya and Hans for the reproducer!
This reverts commit r330416.
The issue was that removing predecessors invalidated uses that we stored
for rewrite. The fix is to finish manipulating with CFG before we select
uses for rewrite.
llvm-svn: 330431
Revert r330413: "[SSAUpdaterBulk] Use SmallVector instead of DenseMap for storing rewrites."
Revert r330403 "Reapply "[PR16756] Use SSAUpdaterBulk in JumpThreading." one more time."
r330403 commit seems to crash clang during our integrate while doing PGO build with the following stacktrace:
#2 llvm::SSAUpdaterBulk::RewriteAllUses(llvm::DominatorTree*, llvm::SmallVectorImpl<llvm::PHINode*>*)
#3 llvm::JumpThreadingPass::ThreadEdge(llvm::BasicBlock*, llvm::SmallVectorImpl<llvm::BasicBlock*> const&, llvm::BasicBlock*)
#4 llvm::JumpThreadingPass::ProcessThreadableEdges(llvm::Value*, llvm::BasicBlock*, llvm::jumpthreading::ConstantPreference, llvm::Instruction*)
#5 llvm::JumpThreadingPass::ProcessBlock(llvm::BasicBlock*)
The crash happens while compiling 'lib/Analysis/CallGraph.cpp'.
r3340413 is reverted due to conflicting changes.
llvm-svn: 330416
Hopefully, changing set to vector removes nondeterminism detected by
some bots, or the new assert will catch something.
This reverts commit r330180.
llvm-svn: 330403
Summary:
The following changes addresses the following two issues.
1) The existing loop rotation pass contains both loop latch simplification and loop rotation. So one flag RotationOnly is added to be passed to the loop rotation pass.
2) The threshold value is initialized with MAX_UINT since the loop rotation utility should not have threshold limit.
Reviewers: dmgreen, efriedma
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D45582
llvm-svn: 330362
Summary:
This fixes the bug pointed out in review with non-trivial unswitching.
This also provides a basis that should make it pretty easy to finish
fleshing out a routine to scan an entire function body for irreducible
control flow, but this patch remains minimal for disabling loop
unswitch.
Reviewers: sanjoy, fedor.sergeev
Subscribers: mcrosier, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D45754
llvm-svn: 330357
If those operands change, we might find a leader for ValueOp, which
could enable new phi-of-op creation.
This fixes a case where we missed creating a phi-of-ops node. With D43865
and this patch, bootstrapping clang/llvm works with -enable-newgvn, whereas
without it, the "value changed after iteration" assertion is triggered.
Reviewers: dberlin, davide
Reviewed By: dberlin
Differential Revision: https://reviews.llvm.org/D42180
llvm-svn: 330334
After investigation discussed in D45439, it would seem that the nsw
flag restriction is unnecessary in most cases. So the IsInductionVar
lambda has been removed, the functionality extracted, and now only
require nsw when using eq/ne predicates.
Differential Revision: https://reviews.llvm.org/D45617
llvm-svn: 330256
One more, hopefully the last, bug is fixed: when forming UsesToRewrite
we should ignore phi operands coming from edges that we want to delete.
This reverts r329910.
llvm-svn: 330175
As suggested in https://reviews.llvm.org/D45631#1068338,
looking at haveNoCommonBitsSet() users, and *trying* to
show the change effect elsewhere.
llvm-svn: 330100
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.
Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.
Reviewers: kcc, pcc, danielcdh, jmolloy, sanjoy, dberlin, ruiu
Reviewed By: ruiu
Subscribers: ruiu, llvm-commits
Differential Revision: https://reviews.llvm.org/D45142
llvm-svn: 330059
Created a helper function to query for non negative SCEVs. Uses the
SGE predicate to catch constants that could be interpreted as
negative.
Differential Revision: https://reviews.llvm.org/D45481
llvm-svn: 329907
This is based on an example that was recently posted on llvm-dev:
void *propagate_null(void* b, int* g) {
if (!b) {
return 0;
}
(*g)++;
return b;
}
https://godbolt.org/g/xYk3qG
The original code or constant propagation in other passes has obscured the fact
that the phi can be removed completely.
Differential Revision: https://reviews.llvm.org/D45448
llvm-svn: 329755
Summary:
SSAUpdater is a bottleneck in JumpThreading, and this patch improves the
situation by using SSAUpdaterBulk instead.
Compile time impact: no noticable changes on CTMark, a big improvement
on the test from PR16756.
Reviewers: dberlin, davide, MatzeB
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D44282
llvm-svn: 329644
Summary:
We do not try to move the instructions and split the block till we
know the blocks can be split, i.e. BCE-cmp-insts can be separated from
non-BCE-cmp-insts.
Reviewers: davide, courbet
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D44443
llvm-svn: 329564
In IRCE, we have a very old legacy check that works when we collect comparisons that we
treat as range checks. It ensures that the value against which the indvar is compared is
loop invariant and is also positive.
This latter condition remained there since the times when IRCE was only able to handle
signed latch comparison. As the optimization evolved, it now learned how to intersect
signed or unsigned ranges, and this logic has no reliance on the fact that the right border
of each range should be positive.
The old implementation of this non-negativity check was also naive enough and just looked
into ranges (while most of other IRCE logic tries to use power of SCEV implications), so this
check did not allow to deal with the most simple case that looks like follows:
int size; // not known non-negative
int length; //known non-negative;
i = 0;
if (size != 0) {
do {
range_check(i < size);
range_check(i < length);
++i;
} while (i < size)
}
In this case, even if from some dominating conditions IRCE could parse loop
structure, it could only remove the range check against `length` and simply
ignored the check against `size`.
In this patch we remove this obsolete check. It will allow IRCE to pick comparison
against `size` as a potential range check and then let Range Intersection logic
decide whether it is OK to eliminate it or not.
Differential Revision: https://reviews.llvm.org/D45362
Reviewed By: samparker
llvm-svn: 329547
LoopInterchange relies on LoopInfo being up-to-date, so we should
preserve it after interchanging. This patch updates restructureLoops to
move the BBs of the interchanged loops to the right place.
Reviewers: davide, efriedma, karthikthecool, mcrosier
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D45278
llvm-svn: 329264
Summary:
If the callsite is inside landing pad, do not perform callsite splitting.
Callsite splitting uses utility function llvm::DuplicateInstructionsInSplitBetween, which eventually calls llvm::SplitEdge. llvm::SplitEdge calls llvm::SplitCriticalEdge with an assumption that the function returns nullptr only when the target edge is not a critical edge (and further assumes that if the return value was not nullptr, the predecessor of the original target edge always has a single successor because critical edge splitting was successful). However, this assumtion is not true because SplitCriticalEdge returns nullptr if the destination block is a landing pad. This invalid assumption results assertion failure.
Fundamental solution might be fixing llvm::SplitEdge to not to rely on the invalid assumption. However, it'll involve a lot of work because current API assumes that llvm::SplitEdge never fails. Instead, this patch makes callsite splitting to not to attempt splitting if the callsite is in a landing pad.
Attached test case will crash with assertion failure without the fix.
Reviewers: fhahn, junbuml, dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45130
llvm-svn: 329250
Fixes cases like the new test @nonuniform. In that test, %cc itself
is a uniform value; however, when reading it after the end of the loop in
basic block %if, its value is effectively non-uniform, so the branch is
non-uniform.
This problem was encountered in
https://bugs.freedesktop.org/show_bug.cgi?id=103743; however, this change
in itself is not sufficient to fix that bug, as there is another issue
in the AMDGPU backend.
As discovered after committing an earlier version of this change, this
exposes a subtle interaction between this pass and DivergenceAnalysis:
since we remove and re-create branch instructions, we can no longer rely
on DivergenceAnalysis for branches in subregions that were already
processed by the pass.
Explicitly remove branch instructions from DivergenceAnalysis to
avoid dangling pointers as a matter of defensive programming, and
change how we detect non-uniform subregions.
Change-Id: I32bbffece4a32f686fab54964dae1a5dd72949d4
Differential Revision: https://reviews.llvm.org/D43743
llvm-svn: 329165
It also updates test/Transforms/LoopInterchange/call-instructions.ll
to use accesses where we can prove dependence after D35430.
Reviewers: sebpop, karthikthecool, blitz.opensource
Reviewed By: sebpop
Differential Revision: https://reviews.llvm.org/D45206
llvm-svn: 329111
For Hexagon, peeling loops with small runtime trip count is beneficial for our
benchmarks. We set PeelCount in HexagonTargetInfo.cpp and we use PeelCount set
by the target for computing the desired peel count.
Differential Revision: https://reviews.llvm.org/D44880
llvm-svn: 329042
In r312664 (D36404), JumpThreading stopped threading edges into
loop headers. Unfortunately, I observed a significant performance
regression as a result of this change. Upon further investigation,
the problematic pattern looked something like this (after
many high level optimizations):
while (true) {
bool cond = ...;
if (!cond) {
<body>
}
if (cond)
break;
}
Now, naturally we want jump threading to essentially eliminate the
second if check and hook up the edges appropriately. However, the
above mentioned change, prevented it from doing this because it would
have to thread an edge into the loop header.
Upon further investigation, what is happening is that since both branches
are threadable, JumpThreading picks one of them at arbitrarily. In my
case, because of the way that the IR ended up, it tended to pick
the one to the loop header, bailing out immediately after. However,
if it had picked the one to the exit block, everything would have
worked out fine (because the only remaining branch would then be folded,
not thraded which is acceptable).
Thus, to fix this problem, we can simply eliminate loop headers from
consideration as possible threading targets earlier, to make sure that
if there are multiple eligible branches, we can still thread one of
the ones that don't target a loop header.
Patch by Keno Fischer!
Differential Revision: https://reviews.llvm.org/D42260
llvm-svn: 328798
The existing LoopRotation.cpp is implemented as one of loop passes instead of
being a utility. The user cannot easily perform the loop rotation selectively
(or on demand) under different optimization level. For example, the loop
rotation is needed as part of the logic to convert a loop into a loop with
bottom test for a transformation. If the loop rotation is simply added as a
loop pass before the transformation, the pass is skipped if it is compiled at
–O0 or if it is explicitly disabled by the user, causing the compiler to
generate incorrect code. Furthermore, as a loop pass it will rotate all loops
instead of just the relevant loops.
We provide a utility interface for the loop rotation so that the loop rotation
can be called on demand. The changeset is as follows:
- Create a new file lib/Transforms/Utils/LoopRotationUtils.cpp and move the main
implementation of class LoopRotate into this file.
- Create a new file llvm/include/Transform/Utils/LoopRotationUtils.h with the
interface LoopRotation(...).
- Original LoopRotation.cpp is changed to use the utility function LoopRotation
in LoopRotationUtils.cpp. This is done in the same way community did for
mem-to-reg implementation.
Patch by Jin Lin!
Differential Revision: https://reviews.llvm.org/D44595
llvm-svn: 328766
As a follow-up to r328480, this updates the logic for the decreasing
safety checks in a similar manner:
- CanBeMax is replaced by CannotBeMaxInLoop which queries
isLoopEntryGuardedByCond on the maximum value.
- SumCanReachMin is replaced by isSafeDecreasingBound which includes
some logic from parseLoopStructure and, again, has been updated to
use isLoopEntryGuardedByCond on the given bounds.
Differential Revision: https://reviews.llvm.org/D44776
llvm-svn: 328613
Implement TTI interface for targets to indicate that the LSR should give
priority to post-incrementing addressing modes.
Combination of patches by Sebastian Pop and Brendon Cahoon.
Differential Revision: https://reviews.llvm.org/D44758
llvm-svn: 328490
CanBeMin is currently used which will report true for any unknown
values, but often a check is performed outside the loop which covers
this situation:
for (int i = 0; i < N; ++i)
...
if (N > 0)
for (int i = 0; i < N; ++i)
...
So I've add 'LoopGuardedAgainstMin' which reports whether N is
greater than the minimum value which then allows loop with a variable
loop count to be optimised. I've also moved the increasing bound
checking into its own function and replaced SumCanReachMax is another
isLoopEntryGuardedByCond function.
llvm-svn: 328480
For comparisons with parameters, we can use the ParamState lattice
elements which also provide constant range information. This improves
the code for PR33253 further and gets us closer to use
ValueLatticeElement for all values.
Also, as we are using the range information in the solver directly, we
do not need tryToReplaceWithConstantRange afterwards anymore.
Reviewers: dberlin, mssimpso, davide, efriedma
Reviewed By: mssimpso
Differential Revision: https://reviews.llvm.org/D43762
llvm-svn: 328307
Transforms/Scalar/SCCP.cpp implemented both the Scalar and IPO SCCP, but
this meant Transforms/Scalar including Transfroms/IPO headers, creating
a circular dependency. (IPO depends on Scalar already) - so move the IPO
SCCP shims out into IPO and the basic library implementation accessible
from Scalar/SCCP.h to be used from the IPO/SCCP.cpp implementation.
llvm-svn: 328250
Summary:
LoopPredication is not profitable when the loop is known to always exit
through some block other than the latch block.
A coarse grained latch check can cause loop predication to predicate the
loop, and unconditionally deoptimize.
However, without predicating the loop, the guard may never fail within the
loop during the dynamic execution because the non-latch loop termination
condition exits the loop before the latch condition causes the loop to
exit.
We teach LP about this using BranchProfileInfo pass.
Reviewers: apilipenko, skatkov, mkazantsev, reames
Reviewed by: skatkov
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D44667
llvm-svn: 328210
The dominator tree analysis can be preserved easily.
Some other kinds of analysis can probably be preserved
too.
Reviewers: junbuml, dberlin
Reviewed By: dberlin
Differential Revision: https://reviews.llvm.org/D43173
llvm-svn: 328206
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.
Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.
Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.
llvm-svn: 328165
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
MemCpyOpt pass to cease using:
1) The old getAlignment() API of MemoryIntrinsic in favour of getting source & dest specific
alignments through the new API.
2) The old IRBuilder CreateMemCpy/CreateMemMove single-alignment APIs in favour of the new
API that allows setting source and destination alignments independently.
We also add a few tests to fill gaps in the testing of this pass.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642, rL324653, rL324654, rL324773, rL324774,
rL324781, rL324784, rL324955, rL324960, rL325816, rL327398, rL327421 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 328097
Summary:
If the operands of a udiv/urem can be proved to fit within a smaller
power-of-two-sized type, reduce the width of the udiv/urem.
Backed out for causing performance regressions. Re-landing
because we've determined that these regressions were noise.
Original Differential Revision: https://reviews.llvm.org/D44102
llvm-svn: 328096
Summary: Fix a bug in entry block shuffled to middle of the chain.
Reviewers: davide, courbet
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D44642
llvm-svn: 327971
LICM deletes trivially dead instructions which it won't attempt to sink.
Attempt to salvage debug values which reference these instructions.
llvm-svn: 327800
JumpThreading iterates over F until the IR quiesces. Transforming
unreachable BBs increases compile time and it is also possible to
never stabilize causing JumpThreading to hang. An older attempt at
fixing this problem was D3991 where removeUnreachableBlocks(F)
was called before JumpThreading began. This has a few drawbacks:
* expensive - the routine attempts to fix up the IR to identify
additional BBs that can be removed along with unreachable BBs.
* aggressive - does not identify and preserve the shape of the IR.
At a minimum it does not preserve loop hierarchies.
* invasive - altering reachable blocks it may disrupt IR shapes
that could have otherwise been JumpThreaded.
This patch avoids removeUnreachableBlocks(F) and instead tracks
unreachable BBs in a SmallPtrSet using DominatorTree to validate the
initial state of all BBs. We then rely on subsequent passes to identify
and remove these unreachable blocks from F.
Reviewers: dberlin, sebpop, kuhar, dinesh.d
Reviewed by: sebpop, kuhar
Subscribers: hiraditya, uabelho, llvm-commits
Differential Revision: https://reviews.llvm.org/D44177
llvm-svn: 327713
If the loop body contains conditions of the form IndVar < #constant, we
can remove the checks by peeling off #constant iterations.
This improves codegen for PR34364.
Reviewers: mkuper, mkazantsev, efriedma
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D43876
llvm-svn: 327671
If we've already established an invariant scope with an earlier generation, we don't want to hide it in the scoped hash table with one with a later generation. I noticed this when working on the invariant-load handling, but it also applies to the invariant.start case as well.
Without this change, my previous patch for invariant-load regresses some cases, so I'm pushing this without waiting for review. This is why you don't make last minute tweaks to patches to catch "obvious cases" after it's already been reviewed. Bad Philip!
llvm-svn: 327655
This is a follow up to https://reviews.llvm.org/D43716 which rewrites the invariant load handling using the new infrastructure. It's slightly more powerful, but only in somewhat minor ways for the moment. It's not clear that DSE of stores to invariant locations is actually interesting since why would your IR have such a construct to start with?
Note: The submitted version is slightly different than the reviewed one. I realized the scope could start for an invariant load which was proven redundant and removed. Added a test case to illustrate that as well.
Differential Revision: https://reviews.llvm.org/D44497
llvm-svn: 327646
There are two nontrivial details here:
* Loop structure update interface is quite different with new pass manager,
so the code to add new loops was factored out
* BranchProbabilityInfo is not a loop analysis, so it can not be just getResult'ed from
within the loop pass. It cant even be queried through getCachedResult as LoopCanonicalization
sequence (e.g. LoopSimplify) might invalidate BPI results.
Complete solution for BPI will likely take some time to discuss and figure out,
so for now this was partially solved by making BPI optional in IRCE
(skipping a couple of profitability checks if it is absent).
Most of the IRCE tests got their corresponding new-pass-manager variant enabled.
Only two of them depend on BPI, both marked with TODO, to be turned on when BPI
starts being available for loop passes.
Reviewers: chandlerc, mkazantsev, sanjoy, asbirlea
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D43795
llvm-svn: 327619
Summary:
Before this patch call graph is like this in the LoopUnrollPass:
tryToUnrollLoop
ApproximateLoopSize
collectEphemeralValues
/* Use collected ephemeral values */
computeUnrollCount
analyzeLoopUnrollCost
/* Bail out from the analysis if loop contains CallInst */
This patch moves collection of the ephemeral values to the tryToUnrollLoop
function and passes the collected values into both ApproximateLoopsize (as
before) and additionally starts using them in analyzeLoopUnrollCost:
tryToUnrollLoop
collectEphemeralValues
ApproximateLoopSize(EphValues)
/* Use EphValues */
computeUnrollCount(EphValues)
analyzeLoopUnrollCost(EphValues)
/* Ignore ephemeral values - they don't contribute to the final cost */
/* Bail out from the analysis if loop contains CallInst */
Reviewers: mzolotukhin, evstupac, sanjoy
Reviewed By: evstupac
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43931
llvm-svn: 327617
If we have an invariant.start with no corresponding invariant.end, then the memory location becomes invariant indefinitely after the invariant.start. As a result, anything dominated by the start is guaranteed to see the value the memory location had when the invariant.start executed.
This patch adds an AvailableInvariants table which tracks the generation a particular memory location became invariant and then uses that information to allow value forwarding that would otherwise be disallowed by potentially aliasing stores. (Reminder: In EarlyCSE everything clobbers everything by default.)
This should be compatible with the MemorySSA variant, but design is generational. We can and should add first class support for invariant.start within MemorySSA at a later time. I took a quick look at doing so, but probably need some input from a MemorySSA expert.
Differential Revision: https://reviews.llvm.org/D43716
llvm-svn: 327577
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
SROA pass to cease using the old getAlignment() & setAlignment() APIs of MemoryIntrinsic in
favour of getting source & dest specific alignments through the new API. This allows us
to enhance visitMemTransferInst to be more aggressive setting the alignment in memcpy
calls that it creates, as well as to only change the alignment of a memcpy/memmove
argument that it replaces.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642, rL324653, rL324654, rL324773, rL324774,
rL324781, rL324784, rL324955, rL324960, rL325816 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
Reviewers: chandlerc, bollu, efriedma
Reviewed By: efriedma
Subscribers: efriedma, eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D42974
llvm-svn: 327398
LoopInstSimplify is unused and untested. Reading through the commit
history the pass also seems to have a high maintenance burden.
It would be best to retire the pass for now. It should be easy to
recover if we need something similar in the future.
Differential Revision: https://reviews.llvm.org/D44053
llvm-svn: 327329
getNumUses is a linear operation. It walks a linked list to get a count. So in this case its better to just ask if there are any users rather than how many.
llvm-svn: 327314
This reverts r326908, originally landed as D44102.
Reverted for causing performance regressions on x86. (These regressions
are not yet understood.)
llvm-svn: 327252
There are six separate instances of getPointerOperand() utility.
LoopVectorize.cpp has one of them,
and I don't want to create a 7th one while I'm trying to move
LoopVectorizationLegality into a separate file
(eventual objective is to move it to Analysis tree).
See http://lists.llvm.org/pipermail/llvm-dev/2018-February/120999.html
for llvm-dev discussions
Closes D43323.
Patch by Hideki Saito <hideki.saito@intel.com>.
llvm-svn: 327173
In r263618, JumpThreading learned to look trough simple cast instructions, but
only if the source of those cast instructions was a phi/cmp i1 (in an effort to
limit compile time effects). I think this condition is too restrictive. For
switches with limited value range, InstCombine will readily introduce an extra
trunc instruction to a smaller integer type (e.g. from i8 to i2), leaving us in
the somewhat perverse situation that jump-threading would work before running
instcombine, but not after. Since instcombine produces this pattern, I think we
need to consider it canonical and support it in JumpThreading. In general,
for limiting recursion, I think the existing restriction to phi and cmp nodes
should be sufficient to avoid looking through unprofitable chains of
instructions.
Patch by Keno Fischer!
Differential Revision: https://reviews.llvm.org/D42262
llvm-svn: 327150
Summary:
If the operands of a udiv/urem can be proved to fit within a smaller
power-of-two-sized type, reduce the width of the udiv/urem.
Backed out for failing an assert in clang bootstrap builds. Re-landing
with a fix for handling non-power-of-two inputs (e.g. udiv i24).
Original Differential Revision: https://reviews.llvm.org/D44102
llvm-svn: 326908
Breaks bootstrap builds: clang built with this patch asserts while
building MCDwarf.cpp: Assertion `castIsValid(op, S, Ty) && "Invalid
cast!"' failed.
llvm-svn: 326900
Summary:
If the operands of a udiv/urem can be proved to fit within a smaller
power-of-two-sized type, reduce the width of the udiv/urem.
Reviewers: spatel, sanjoy
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D44102
llvm-svn: 326898
It's been quite some time the Dependence Analysis (DA) is broken,
as it uses the GEP representation to "identify" multi-dimensional arrays.
It even wrongly detects multi-dimensional arrays in single nested loops:
from test/Analysis/DependenceAnalysis/Coupled.ll, example @couple6
;; for (long int i = 0; i < 50; i++) {
;; A[i][3*i - 6] = i;
;; *B++ = A[i][i];
DA used to detect two subscripts, which makes no sense in the LLVM IR
or in C/C++ semantics, as there are no guarantees as in Fortran of
subscripts not overlapping into a next array dimension:
maximum nesting levels = 1
SrcPtrSCEV = %A
DstPtrSCEV = %A
using GEPs
subscript 0
src = {0,+,1}<nuw><nsw><%for.body>
dst = {0,+,1}<nuw><nsw><%for.body>
class = 1
loops = {1}
subscript 1
src = {-6,+,3}<nsw><%for.body>
dst = {0,+,1}<nuw><nsw><%for.body>
class = 1
loops = {1}
Separable = {}
Coupled = {1}
With the current patch, DA will correctly work on only one dimension:
maximum nesting levels = 1
SrcSCEV = {(-2424 + %A)<nsw>,+,1212}<%for.body>
DstSCEV = {%A,+,404}<%for.body>
subscript 0
src = {(-2424 + %A)<nsw>,+,1212}<%for.body>
dst = {%A,+,404}<%for.body>
class = 1
loops = {1}
Separable = {0}
Coupled = {}
This change removes all uses of GEP from DA, and we now only rely
on the SCEV representation.
The patch does not turn on -da-delinearize by default, and so the DA analysis
will be more conservative in the case of multi-dimensional memory accesses in
nested loops.
I disabled some interchange tests, as the DA is not able to disambiguate
the dependence anymore. To make DA stronger, we may need to
compute a bound on the number of iterations based on the access functions
and array dimensions.
The patch cleans up all the CHECKs in test/Transforms/LoopInterchange/*.ll to
avoid checking for snippets of LLVM IR: this form of checking is very hard to
maintain. Instead, we now check for output of the pass that are more meaningful
than dozens of lines of LLVM IR. Some tests now require -debug messages and thus
only enabled with asserts.
Patch written by Sebastian Pop and Aditya Kumar.
Differential Revision: https://reviews.llvm.org/D35430
llvm-svn: 326837
Change doCallSiteSplitting to iterate until we reach the terminator instruction.
tryToSplitCallSite can replace BB's terminator in case BB is a successor of
itself. Then IE will be invalidated and we also have to check the current
terminator.
Reviewers: junbuml, davidxl, davide, fhahn
Reviewed By: fhahn, junbuml
Differential Revision: https://reviews.llvm.org/D43824
llvm-svn: 326793
Summary:
RewriteStatepointsForGC collects parse points for further processing.
During the collection if a callsite is found in an unreachable block
(DominatorTree::isReachableFromEntry()) then all unreachable blocks are
removed by removeUnreachableBlocks(). Some of the removed blocks could
have been reachable according to DominatorTree::isReachableFromEntry().
In this case the collected parse points became stale and resulted in a
crash when accessed.
The fix is to unconditionally canonicalize the IR to
removeUnreachableBlocks and then collect the parse points.
The added test crashes with the old version and passes with this patch.
Patch by Yevgeny Rouban!
Reviewed by: Anna
Differential Revision: https://reviews.llvm.org/D43929
llvm-svn: 326748
getCompare returns true, false or undef constants if the comparison can
be evaluated, or nullptr if it cannot. This is in line with what
ConstantExpr::getCompare returns. It also allows us to use
ConstantExpr::getCompare for comparing constants.
Reviewers: davide, mssimpso, dberlin, anna
Reviewed By: davide
Differential Revision: https://reviews.llvm.org/D43761
llvm-svn: 326720
Summary:
We can discard initial blocks that do other work
We do not need to limit ourselves to just the first block in the chain.
Reviewers: courbet, davide
Reviewed By: courbet
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D44029
llvm-svn: 326698
Iterating through predecessors of `TailBB` while removing their
terminators leads to use after-free, because the predecessor list is
changing on each removal.
llvm-svn: 326668
Summary:
`musttail` calls can't be naively splitted. The split blocks must
include not only the call instruction itself, but also (optional)
`bitcast` and `return` instructions that follow it.
Clone `bitcast` and `ret`, place them into the split blocks, and
remove the tail block when done.
Reviewers: junbuml, mcrosier, davidxl, davide, fhahn
Reviewed By: fhahn
Subscribers: JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D43729
llvm-svn: 326666
Currently when AllowRemainder is disabled, pragma unroll count is not
respected even though there is no remainder. This bug causes a loop
fully unrolled in many cases even though the user specifies a unroll
count. Especially it affects OpenCL/CUDA since in many cases a loop
contains convergent instructions and currently AllowRemainder is
disabled for such loops.
Differential Revision: https://reviews.llvm.org/D43826
llvm-svn: 326585
Do not replace results of `musttail` calls with a constant if the
call itself can't be removed.
Do not zap returns of `musttail` callees, if the call site can't be
removed and replaced with a constant.
Do not zap returns of `musttail`-calling blocks, this breaks
invariant too.
Patch by Fedor Indutny
Differential Revision: https://reviews.llvm.org/D43695
llvm-svn: 326404
Summary:
Fix a bug in MergeICmp that can lead to a BCECmp block being processed more than once and eventually lead to a broken LLVM module.
The problem is that if the non-constant value is not produced by the last block, the producer will be processed once when the its parent block
is processed and second time when the last block is processed.
We end up having 2 same BCECmpBlock in the merge queue. And eventually lead to a broken LLVM module.
Reviewers: courbet, davide
Reviewed By: courbet
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43825
llvm-svn: 326318
Removes verifyDomTree, using assert(verify()) everywhere instead, and
changes verify a little to always run IsSameAsFreshTree first in order
to print good output when we find errors. Also adds verifyAnalysis for
PostDomTrees, which will allow checking of PostDomTrees it the same way
we check DomTrees and MachineDomTrees.
Differential Revision: https://reviews.llvm.org/D41298
llvm-svn: 326315
In case we update a ValuePHI node created earlier, we could update it
based on a different OpPHI which could be in a different block.
We need to update the TempToBlock mapping reflecting the new block,
otherwise we would end up placing the new phi node in a wrong block.
This problem is exposed by the test case in
https://bugs.llvm.org/show_bug.cgi?id=36504.
This patch fixes a slightly simpler problem than in the bug report. In
the bug's re-producer, the additional problem is that we are re-using a
ValuePHI node with to few incoming values for the new OpPHI. If this
patch makes sense, I will follow it up with a patch that creates a new
PHI node if the existing PHI node has a different number of incoming
values.
Reviewers: davide, dberlin
Reviewed By: dberlin
Differential Revision: https://reviews.llvm.org/D43770
llvm-svn: 326181
The dependency matrix is only empty if no conflicting load/store
instructions have been found. In that case, it is safe to interchange.
For the LLVM test-suite, after this change around 1900 loops are
interchanged, whereas it is 15 before this change. On cortex-a57,
this gives an improvement of -0.57% on the geomean execution
time of SPEC2006, SPEC2000 and the test-suite. There are a
few small perf regressions, but I think we can improve on those
by making the cost model better.
Reviewers: karthikthecool, mcrosier
Reviewed by: karthikthecool
Differential Revision: https://reviews.llvm.org/D43236
llvm-svn: 326077
Summary:
This fixes cases like the new test @nonuniform. In that test, %cc itself
is a uniform value; however, when reading it after the end of the loop in
basic block %if, its value is effectively non-uniform.
This problem was encountered in
https://bugs.freedesktop.org/show_bug.cgi?id=103743; however, this change
in itself is not sufficient to fix that bug, as there is another issue
in the AMDGPU backend.
Change-Id: I32bbffece4a32f686fab54964dae1a5dd72949d4
Reviewers: arsenm, rampitec, jlebar
Subscribers: wdng, tpr, llvm-commits
Differential Revision: https://reviews.llvm.org/D40546
llvm-svn: 325881
Summary:
MemDep caches results that signify that a dependence is non-local, and
there is currently no way to invalidate such cache entries.
Unfortunately, when MLSM sinks a store that can result in a non-local
dependence becoming a local one, and then MemDep gives wrong answers.
The easiest way out here is to just say that MLSM does indeed not
preserve MemDep results.
Reviewers: davide, Gerolf
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43177
llvm-svn: 325880
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
AlignmentFromAssumptions pass to cease using the old getAlignment()/setAlignment API of
MemoryIntrinsic in favour of getting/setting source & dest specific alignments through
the new API. This allows us to simplify some of the code in this pass and also be more
aggressive about setting the source and destination alignments separately.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642, rL324653, rL324654, rL324773, rL324774,
rL324781, rL324784, rL324955, rL324960 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
Reviewers: hfinkel, bollu, reames
Reviewed By: reames
Subscribers: reames, llvm-commits
Differential Revision: https://reviews.llvm.org/D43081
llvm-svn: 325816
This results in 15 additional unique source variables in a stage2 build
of FileCheck (at '-Os -g'), with a negligible increase in the size of
the .debug_loc section.
llvm-svn: 325660
Summary:
We used to remove the first memmove in cases like this:
memmove(p, p+2, 8);
memmove(p, p+2, 8);
which is incorrect. Fix this by changing isPossibleSelfRead to what was most
likely the intended behavior.
Historical note: the buggy code was added in https://reviews.llvm.org/rL120974
to address PR8728.
Reviewers: rsmith
Subscribers: mcrosier, llvm-commits, jlebar
Differential Revision: https://reviews.llvm.org/D43425
llvm-svn: 325641
Summary:
The LazyValueInfo pass caches a copy of the DominatorTree when available.
Whenever there are pending DominatorTree updates within JumpThreading's
DeferredDominance object we cannot use the cached DT for LVI analysis.
This commit adds the new methods enableDT() and disableDT() to LVI.
JumpThreading also sets the appropriate usage model before calling LVI
analysis methods.
Fixes https://bugs.llvm.org/show_bug.cgi?id=36133
Reviewers: sebpop, dberlin, kuhar
Reviewed by: sebpop, kuhar
Subscribers: uabelho, llvm-commits, aprantl, hiraditya, a.elovikov
Differential Revision: https://reviews.llvm.org/D42717
llvm-svn: 325356
Now that we have the new TBAA metadata format that is capable of
representing accesses to aggregates, we can propagate TBAA access
tags from memory setting and transferring intrinsics to load and
store instructions and vice versa.
Since SROA produces lots of new loads and stores on optimized
builds, this change significantly decreases the share of
undecorated memory accesses on such builds.
Differential Revision: https://reviews.llvm.org/D41563
llvm-svn: 325329
In r325063, we salvaged debug values from dying instructions in
GVN::processBlock() and GVN::performScalarPRE().
The change in performScalarPRE(), while correct, is unhelpful. It
introduced a call to salvageDebugInfo() which was immediately followed
by a RAUW, meaning it prevented the RAUW from efficiently updating
dbg.value intrinsics. This commit reverts the mistake and tightens up
the affected test case.
llvm-svn: 325308
This results in small increases in the size of the .debug_loc section
and the number of unique source variables in a stage2 build of opt.
llvm-svn: 325301
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
For basic blocks with instructions between the beginning of the block
and a call we have to duplicate the instructions before the call in all
split blocks and add PHI nodes for uses of the duplicated instructions
after the call.
Currently, the threshold for the number of instructions before a call
is quite low, to keep the impact on binary size low.
Reviewers: junbuml, mcrosier, davidxl, davide
Reviewed By: junbuml
Differential Revision: https://reviews.llvm.org/D41860
llvm-svn: 325126
We can use incremental dominator tree updates to avoid re-calculating
the dominator tree after interchanging 2 loops.
Reviewers: dmgreen, kuhar
Reviewed By: kuhar
Differential Revision: https://reviews.llvm.org/D43176
llvm-svn: 325122
Making a width of GEP Index, which is used for address calculation, to be one of the pointer properties in the Data Layout.
p[address space]:size:memory_size:alignment:pref_alignment:index_size_in_bits.
The index size parameter is optional, if not specified, it is equal to the pointer size.
Till now, the InstCombiner normalized GEPs and extended the Index operand to the pointer width.
It works fine if you can convert pointer to integer for address calculation and all registered targets do this.
But some ISAs have very restricted instruction set for the pointer calculation. During discussions were desided to retrieve information for GEP index from the Data Layout.
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120416.html
I added an interface to the Data Layout and I changed the InstCombiner and some other passes to take the Index width into account.
This change does not affect any in-tree target. I added tests to cover data layouts with explicitly specified index size.
Differential Revision: https://reviews.llvm.org/D42123
llvm-svn: 325102
This preserves an additional 581 unique source variables in a stage2
build of clang (according to `llvm-dwarfdump --statistics`). It
increases the size of the .debug_loc section by 0.1% (or 87139 bytes).
Differential Revision: https://reviews.llvm.org/D43255
llvm-svn: 325063
According to `llvm-dwarfdump --statistics` this salvages 43 additional
unique source variables in a stage2 build of clang. It increases the
size of the .debug_loc section by 0.002% (or 2864 bytes).
Differential Revision: https://reviews.llvm.org/D43220
llvm-svn: 325035
For basic blocks with instructions between the beginning of the block
and a call we have to duplicate the instructions before the call in all
split blocks and add PHI nodes for uses of the duplicated instructions
after the call.
Currently, the threshold for the number of instructions before a call
is quite low, to keep the impact on binary size low.
Reviewers: junbuml, mcrosier, davidxl, davide
Reviewed By: junbuml
Differential Revision: https://reviews.llvm.org/D41860
llvm-svn: 325001
In cases where the OuterMostLoopLatchBI only has a single successor,
accessing the second successor will fail.
This fixes a failure when building the test-suite with loop-interchange
enabled.
Reviewers: mcrosier, karthikthecool, davide
Reviewed by: karthikthecool
Differential Revision: https://reviews.llvm.org/D42906
llvm-svn: 324994
Update BlockColors after splitting predecessors. Do not allow splitting
EHPad for sinking when the BlockColors is not empty, so we can
simply assign predecessor's color to the new block.
Fixes PR36184
llvm-svn: 324916
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
LoopIdiom pass to cease using the old IRBuilder CreateMemCpy single-alignment APIs in
favour of the new API that allows setting source and destination alignments independently.
This allows us to be slightly more aggressive in setting the alignment of memcpy calls that
loop idiom creates.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324626
Summary:
GVN hoist pass is using PostDominatorTree analysis, therefore the analysis
should be listed in the pass initialization as a dependency.
Reviewed By: sebpop
Differential Revision: https://reviews.llvm.org/D43007
Author: ashlykov <arkady.shlykov@intel.com>
llvm-svn: 324597
Add support of uge and sge latch condition to Loop Prediction for
reverse loops.
Reviewers: apilipenko, mkazantsev, sanjoy, anna
Reviewed By: anna
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42837
llvm-svn: 324589
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
DeadStoreElimination pass to cease using the old getAlignment() API of MemoryIntrinsic
in favour of getting dest specific alignments through the new API.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324402
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
InferAddressSpaces pass to cease using:
1) The old getAlignment() API of MemoryIntrinsic in favour of getting source & dest specific
alignments through the new API.
2) The old IRBuilder CreateMemCpy/CreateMemMove single-alignment APIs in favour of the new
API that allows setting source and destination alignments independently.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324395
- Fix condition for detecting that a complex basic block was the first in
the chain.
- Add tests.
This was caught by buildbots when submitting rL324319.
llvm-svn: 324341
In the motivating case from PR35681 and represented by the macro-fuse-cmp test:
https://bugs.llvm.org/show_bug.cgi?id=35681
...there's a 37 -> 31 byte size win for the loop because we eliminate the big base
address offsets.
SPEC2017 on Ryzen shows no significant perf difference.
Differential Revision: https://reviews.llvm.org/D42607
llvm-svn: 324289
ScalarEvolution::isKnownPredicate invokes isLoopEntryGuardedByCond without check
that SCEV is available at entry point of the loop. It is incorrect and fixed by patch.
To bugs additionally fixed:
assert is moved after the check whether loop is not a nullptr.
Usage of isLoopEntryGuardedByCond in ScalarEvolution::isImpliedCondOperandsViaNoOverflow
is guarded by isAvailableAtLoopEntry.
Reviewers: sanjoy, mkazantsev, anna, dorit, reames
Reviewed By: mkazantsev
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42417
llvm-svn: 324204
Summary:
Before emitting code for scaled registers, we prevent
SCEVExpander from hoisting any scaled addressing mode
by emitting all the bases first. However, these bases
are being forced to the final type, resulting in some
odd code.
For example, if the type of the base is an integer and
the final type is a pointer, we will emit an inttoptr
for the base, a ptrtoint for the scale, and then a
'reverse' GEP where the GEP pointer is actually the base
integer and the index is the pointer. It's more intuitive
to use the pointer as a pointer and the integer as index.
Patch by: Bevin Hansson
Reviewers: atrick, qcolombet, sanjoy
Reviewed By: qcolombet
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42103
llvm-svn: 323946
Summary:
There's an asymmetry in the definitions of findBaseDefiningValueOfVector() and
findBaseDefiningValue() of RS4GC. The later handles call and invoke instructions,
and the former does not. This appears to be simple oversight. This patch remedies
the oversight by adding the call and invoke cases to findBaseDefiningValueOfVector().
Reviewers: DaniilSuchkov, anna
Reviewed By: anna
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42653
llvm-svn: 323764
Summary:
The JumpThreading pass has several locations where to the variable name LI
refers to a LoadInst type. This is confusing and inhibits the ability to use
LI for LoopInfo as a member of the JumpThreading class. Minor formatting
and comments were also altered to reflect this change.
Reviewers: dberlin, kuba, spop, sebpop
Reviewed by: sebpop
Subscribers: sebpop, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D42601
llvm-svn: 323695
This pretty much reverts r322006, except that we keep the test,
because we work around the issue exposed in a different way (a
recursion limit in value tracking). There's still probably some
sequence that exposes this problem, and the proper way to fix that
for somebody who has time is outlined in the code review.
llvm-svn: 323630
- using qualified pointer addrspace in intrinsics class to avoid .f32 mangling
- changed too common atomic mangling to ds
- added missing intrinsics to AMDGPUTTIImpl::getTgtMemIntrinsic
Reviewed by: b-sumner
Differential Revision: https://reviews.llvm.org/D42383
llvm-svn: 323516
Max Kazantsev