This reverts commit 4e413e1621,
which landed almost 10 months ago under premise that the original behavior
didn't match reality and was breaking users, even though it was correct as per
the LangRef. But the LangRef change still hasn't appeared, which might suggest
that the affected parties aren't really worried about this problem.
Please refer to discussion in:
* https://reviews.llvm.org/D87399 (`Revert "[InstCombine] erase instructions leading up to unreachable"`)
* https://reviews.llvm.org/D53184 (`[LangRef] Clarify semantics of volatile operations.`)
* https://reviews.llvm.org/D87149 (`[InstCombine] erase instructions leading up to unreachable`)
clang has `-Wnull-dereference` which will diagnose the obvious cases
of null dereference, it was adjusted in f4877c78c0,
but it will only catch the cases where the pointer is a null literal,
it will not catch the cases where an arbitrary store is expected to trap.
Differential Revision: https://reviews.llvm.org/D105338
Added check for switch-terminated blocks in loops.
Now if a block is terminated with a switch, we try to find out which of the
cases is taken on 1st iteration and mark corresponding edge from the block
to the case successor as live.
Patch by Dmitry Makogon!
Differential Revision: https://reviews.llvm.org/D105688
Reviewed By: nikic, mkazantsev
This patch removes the IsPairwiseForm flag from the Reduction Cost TTI
hooks, along with some accompanying code for pattern matching reductions
from trees starting at extract elements. IsPairWise is now assumed to be
false, which was the predominant way that the value was used from both
the Loop and SLP vectorizers. Since the adjustments such as D93860, the
SLP vectorizer has not relied upon this distinction between paiwise and
non-pairwise reductions.
This also removes some code that was detecting reductions trees starting
from extract elements inside the costmodel. This case was
double-counting costs though, adding the individual costs on the
individual instruction _and_ the total cost of the reduction. Removing
it changes the costs in llvm/test/Analysis/CostModel/X86/reduction.ll to
not double count. The cost of reduction intrinsics is still tested
through the various tests in
llvm/test/Analysis/CostModel/X86/reduce-xyz.ll.
Differential Revision: https://reviews.llvm.org/D105484
There was an alias between 'simplifycfg' and 'simplify-cfg' in the
PassRegistry. That was the original reason for this patch, which
effectively removes the alias.
This patch also replaces all occurrances of 'simplify-cfg'
by 'simplifycfg'. Reason for choosing that form for the name is
that it matches the DEBUG_TYPE for the pass, and the legacy PM name
and also how it is spelled out in other passes such as
'loop-simplifycfg', and in other options such as
'simplifycfg-merge-cond-stores'.
I for some reason the name should be changed to 'simplify-cfg' in
the future, then I think such a renaming should be more widely done
and not only impacting the PassRegistry.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D105627
C++23 will make these conversions ambiguous - so fix them to make the
codebase forward-compatible with C++23 (& a follow-up change I've made
will make this ambiguous/invalid even in <C++23 so we don't regress
this & it generally improves the code anyway)
Patch tries to improve the vectorization of stores. Originally, we just
check the type and the base pointer of the store.
Patch adds some extra checks to avoid non-profitable vectorization
cases. It includes analysis of the scalar values to be stored and
triggers the vectorization attempt only if the scalar values have
same/alt opcode and are from same basic block, i.e. we don't end up
immediately with the gather node, which is not profitable.
This also improves compile time by filtering out non-profitable cases.
Part of D57059.
Differential Revision: https://reviews.llvm.org/D104122
Revived D101297 in its original form + added some changes in X86
legalization cehcking for masked gathers.
This solution is the most stable and the most correct one. We have to
check the legality before trying to build the masked gather in SLP.
Without this check we have incorrect cost (for SLP) in case if the masked gather
is not legal/slower than the gather. And we're missing some
vectorization opportunities.
This can be fixed in the cost model, but in this case we need to add
special checks for the cost of GEPs for ScatterVectorize node, add
special check for small trees, etc., i.e. there are a lot of corner
cases here and there, which insrease code base and make it harder to
maintain the code.
> Can't we rely on cost model to deal with this? This can be profitable for futher vectorization, when we can start from such gather loads as seed.
The question from D101297. Actually, no, it can't. Actually, simple
gather may give us better result, especially after we started
vectorization of insertelements. Plus, like I said before, the cost for
non-legal masked gathers leads to missed vectorization opportunities.
Differential Revision: https://reviews.llvm.org/D105042
Some of the SPEC tests end up with reduction+(sext/zext(<n x i1>) to <n x im>) pattern, which can be transformed to [-]zext/trunc(ctpop(bitcast <n x i1> to in)) to im.
Also, reduction+(<n x i1>) can be transformed to ctpop(bitcast <n x i1> to in) & 1 != 0.
Differential Revision: https://reviews.llvm.org/D105587
- ``externally_initialized`` variables would be initialized or modified
elsewhere. Particularly, CUDA or HIP may have host code to initialize
or modify ``externally_initialized`` device variables, which may not
be explicitly referenced on the device side but may still be used
through the host side interfaces. Not preserving them triggers the
elimination of them in the GlobalDCE and breaks the user code.
Reviewed By: yaxunl
Differential Revision: https://reviews.llvm.org/D105135
This adds support for opaque pointers to expandAddToGEP() by always
generating an i8 GEP for opaque pointers. After looking at some other
cases (constexpr GEP folding, SROA GEP generation), I've come around
to the idea that we should use i8 GEPs for opaque pointers, because
the alternative would be to guess a GEP type from surrounding code,
which will not be reliable. Ultimately, i8 GEPs is where we want to
end up anyway, and opaque pointers just make that the natural choice.
There are a couple of other places in SCEVExpander that check pointer
element types, I plan to update those when I run across usable test
coverage that doesn't assert elsewhere.
Differential Revision: https://reviews.llvm.org/D105398
The reduction matching was probably only dealing with binops
when it was written, but we have now generalized it to handle
select and intrinsics too, so assert on that too.
Before this patch we would normally use the ABI alignment which can be
to high for the context alginment.
For spilled values we don't need ABI alignment, since the frame entry's
address is not escaped.
rdar://79664965
Differential Revision: https://reviews.llvm.org/D105288
Resubmit after the following changes:
* Fix a latent bug related to unrolling with required epilogue (see e49d65f). I believe this is the cause of the prior PPC buildbot failure.
* Disable non-latch exits for epilogue vectorization to be safe (9ffa90d)
* Split out assert movement (600624a) to reduce churn if this gets reverted again.
Previous commit message (try 3)
Resubmit after fixing test/Transforms/LoopVectorize/ARM/mve-gather-scatter-tailpred.ll
Previous commit message...
This is a resubmit of 3e5ce4 (which was reverted by 7fe41ac). The original commit caused a PPC build bot failure we never really got to the bottom of. I can't reproduce the issue, and the bot owner was non-responsive. In the meantime, we stumbled across an issue which seems possibly related, and worked around a latent bug in 80e8025. My best guess is that the original patch exposed that latent issue at higher frequency, but it really is just a guess.
Original commit message follows...
If we know that the scalar epilogue is required to run, modify the CFG to end the middle block with an unconditional branch to scalar preheader. This is instead of a conditional branch to either the preheader or the exit block.
The motivation to do this is to support multiple exit blocks. Specifically, the current structure forces us to identify immediate dominators and *which* exit block to branch from in the middle terminator. For the multiple exit case - where we know require scalar will hold - these questions are ill formed.
This is the last change needed to support multiple exit loops, but since the diffs are already large enough, I'm going to land this, and then enable separately. You can think of this as being NFCIish prep work, but the changes are a bit too involved for me to feel comfortable tagging the review that way.
Differential Revision: https://reviews.llvm.org/D94892
Before we replaced value by registering all their uses. However, as we
replace a value old uses become stale. We now replace values explicitly
and keep track of "new values" when doing so to avoid replacing only
uses in stale/old values but not their replacements.
We often need to deal with the value lattice that contains none and
undef as special values. A simple helper makes this much nicer.
Differential Revision: https://reviews.llvm.org/D103857
When we do simplification via AAPotentialValues or AAValueConstantRange
we need to simplify the operands of an instruction we deconstruct first.
This does not only improve the result, see for example range.ll, but is
required as we allow outside AAs to provide simplification rules via
callbacks. If we do ignore the simplification rules and base other
simplifications on the IR instead we can create an inconsistent state.
As part of making ScalarEvolution's handling of pointers consistent, we
want to forbid multiplying a pointer by -1 (or any other value). This
means we can't blindly subtract pointers.
There are a few ways we could deal with this:
1. We could completely forbid subtracting pointers in getMinusSCEV()
2. We could forbid subracting pointers with different pointer bases
(this patch).
3. We could try to ptrtoint pointer operands.
The option in this patch is more friendly to non-integral pointers: code
that works with normal pointers will also work with non-integral
pointers. And it seems like there are very few places that actually
benefit from the third option.
As a minimal patch, the ScalarEvolution implementation of getMinusSCEV
still ends up subtracting pointers if they have the same base. This
should eliminate the shared pointer base, but eventually we'll need to
rewrite it to avoid negating the pointer base. I plan to do this as a
separate step to allow measuring the compile-time impact.
This doesn't cause obvious functional changes in most cases; the one
case that is significantly affected is ICmpZero handling in LSR (which
is the source of almost all the test changes). The resulting changes
seem okay to me, but suggestions welcome. As an alternative, I tried
explicitly ptrtoint'ing the operands, but the result doesn't seem
obviously better.
I deleted the test lsr-undef-in-binop.ll becuase I couldn't figure out
how to repair it to test what it was actually trying to test.
Recommitting with fix to MemoryDepChecker::isDependent.
Differential Revision: https://reviews.llvm.org/D104806
When skimming through old review discussion, I noticed a post commit comment on an earlier patch which had gone unaddressed. Better late (4 months), than never right?
I'm not aware of an active problem with the combination of non-latch exits and epilogue vectorization, but the interaction was not considered and I'm not modivated to make epilogue vectorization work with early exits. If there were a bug in the interaction, it would be pretty hard to hit right now (as we canonicalize towards bottom tested loops), but an upcoming change to allow multiple exit loops will greatly increase the chance for error. Thus, let's play it safe for now.
As part of making ScalarEvolution's handling of pointers consistent, we
want to forbid multiplying a pointer by -1 (or any other value). This
means we can't blindly subtract pointers.
There are a few ways we could deal with this:
1. We could completely forbid subtracting pointers in getMinusSCEV()
2. We could forbid subracting pointers with different pointer bases
(this patch).
3. We could try to ptrtoint pointer operands.
The option in this patch is more friendly to non-integral pointers: code
that works with normal pointers will also work with non-integral
pointers. And it seems like there are very few places that actually
benefit from the third option.
As a minimal patch, the ScalarEvolution implementation of getMinusSCEV
still ends up subtracting pointers if they have the same base. This
should eliminate the shared pointer base, but eventually we'll need to
rewrite it to avoid negating the pointer base. I plan to do this as a
separate step to allow measuring the compile-time impact.
This doesn't cause obvious functional changes in most cases; the one
case that is significantly affected is ICmpZero handling in LSR (which
is the source of almost all the test changes). The resulting changes
seem okay to me, but suggestions welcome. As an alternative, I tried
explicitly ptrtoint'ing the operands, but the result doesn't seem
obviously better.
I deleted the test lsr-undef-in-binop.ll becuase I couldn't figure out
how to repair it to test what it was actually trying to test.
Differential Revision: https://reviews.llvm.org/D104806
Code assumes that uses of single predecessor phis are not live accross
suspend points. Cleanup any single predecessor phis preceeding the code
making this assumption.
rdar://76020301
Differential Revision: https://reviews.llvm.org/D105488
Compare type IDs and DFS numbering for basic block instead of addresses
to fix non-determinism.
Differential Revision: https://reviews.llvm.org/D105031
The resume partial functions generated for swift suspend points will now
use a Swift mangling suffix.
Await resume partial functions will use the suffix 'TQ'[0-9]+'_' (e.g "...TQ0_")
and suspend resume partial functions will use the suffix 'TY'[0-9]+'_'
(e.g "...TY1_").
Reviewed By: nate_chandler
Differential Revision: https://reviews.llvm.org/D104144
This reverts commit 706bbfb35b.
The committed version moves the definition of VPReductionPHIRecipe out
of an ifdef only intended for ::print helpers. This should resolve the
build failures that caused the revert
This patch adds a TTI function, isElementTypeLegalForScalableVector, to query
whether it is possible to vectorize a given element type. This is called by
isLegalToVectorizeInstTypesForScalable to reject scalable vectorization if
any of the instruction types in the loop are unsupported, e.g:
int foo(__int128_t* ptr, int N)
#pragma clang loop vectorize_width(4, scalable)
for (int i=0; i<N; ++i)
ptr[i] = ptr[i] + 42;
This example currently crashes if we attempt to vectorize since i128 is not a
supported type for scalable vectorization.
Reviewed By: sdesmalen, david-arm
Differential Revision: https://reviews.llvm.org/D102253
This reverts commit 3fed6d443f,
bbcbf21ae6 and
6c3451cd76.
The changes causing build failures with certain configurations, e.g.
https://lab.llvm.org/buildbot/#/builders/67/builds/3365/steps/6/logs/stdio
lib/libLLVMVectorize.a(LoopVectorize.cpp.o): In function `llvm::VPRecipeBuilder::tryToCreateWidenRecipe(llvm::Instruction*, llvm::ArrayRef<llvm::VPValue*>, llvm::VFRange&, std::unique_ptr<llvm::VPlan, std::default_delete<llvm::VPlan> >&) [clone .localalias.8]':
LoopVectorize.cpp:(.text._ZN4llvm15VPRecipeBuilder22tryToCreateWidenRecipeEPNS_11InstructionENS_8ArrayRefIPNS_7VPValueEEERNS_7VFRangeERSt10unique_ptrINS_5VPlanESt14default_deleteISA_EE+0x63b): undefined reference to `vtable for llvm::VPReductionPHIRecipe'
collect2: error: ld returned 1 exit status
This patch is a first step towards splitting up VPWidenPHIRecipe into
separate recipes for the 3 distinct cases they model:
1. reduction phis,
2. first-order recurrence phis,
3. pointer induction phis.
This allows untangling the code generation and allows us to reduce the
reliance on LoopVectorizationCostModel during VPlan code generation.
Discussed/suggested in D100102, D100113, D104197.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D104989
Splits `getSmallestAndWidestTypes` into two functions, one of which now collects
a list of all element types found in the loop (`ElementTypesInLoop`). This ensures we do not
have to iterate over all instructions in the loop again in other places, such as in D102253
which disables scalable vectorization of a loop if any of the instructions use invalid types.
Reviewed By: sdesmalen
Differential Revision: https://reviews.llvm.org/D105437
that release the retained object
This patch fixes what looks like a longstanding bug in ARC optimizer
where it reverses the order of objc_retain calls and objc_release calls
that retain and release the same object.
The code in ARC optimizer that is responsible for code motion takes the
following steps:
1. Traverse the CFG bottom-up and determine how far up objc_release
calls can be moved. Determine the insertion points for the
objc_release calls, but don't actually move them.
2. Traverse the CFG top-down and determine how far down objc_retain
calls can be moved. Determine the insertion points for the
objc_retain calls, but don't actually move them.
3. Try to move the objc_retain and objc_release calls if they can't be
removed.
The problem is that the insertion points for the objc_retain calls are
determined in step 2 without taking into consideration the insertion
points for objc_release calls determined in step 1, so the order of an
objc_retain call and an objc_release call can be reversed, which is
incorrect, even though each step is correct in isolation.
To fix this bug, this patch teaches the top-down traversal step to take
into consideration the insertion points for objc_release calls
determined in the bottom-up traversal step. Code motion for an
objc_retain call is disabled if there is a possibility that it can be
moved past an objc_release call that releases the retained object.
rdar://79292791
Differential Revision: https://reviews.llvm.org/D104953
This follows up patches for the unsigned siblings:
0c400e8953c7b658aeb5
We are translating an offset signed compare to its
unsigned equivalent when one end of the range is
at the limit (zero or unsigned max).
(X + C2) >s C --> X <u (SMAX - C) (if C == C2 - 1)
(X + C2) <s C --> X >u (C ^ SMAX) (if C == C2)
This probably does not show up much in IR derived
from C/C++ source because that would likely have
'nsw', and we have folds for that already.
As with the previous unsigned transforms, the folds
could be generalized to handle non-constant patterns:
https://alive2.llvm.org/ce/z/Y8Xrrm
; sgt
define i1 @src(i8 %a, i8 %c) {
%c2 = add i8 %c, 1
%t = add i8 %a, %c2
%ov = icmp sgt i8 %t, %c
ret i1 %ov
}
define i1 @tgt(i8 %a, i8 %c) {
%c_off = sub i8 127, %c ; SMAX
%ov = icmp ult i8 %a, %c_off
ret i1 %ov
}
https://alive2.llvm.org/ce/z/c8uhnk
; slt
define i1 @src(i8 %a, i8 %c) {
%t = add i8 %a, %c
%ov = icmp slt i8 %t, %c
ret i1 %ov
}
define i1 @tgt(i8 %a, i8 %c) {
%c_offnot = xor i8 %c, 127 ; SMAX
%ov = icmp ugt i8 %a, %c_offnot
ret i1 %ov
}
The function vectorizeChainsInBlock does not support scalable vector,
because function like canReuseExtract and isCommutative in the code
path assert with scalable vectors.
This patch avoids vectorizing blocks that have extract instructions with scalable
vector..
Differential Revision: https://reviews.llvm.org/D104809
This patch fixes an issue which occurred in CodeGenPrepare and
HWAddressSanitizer, which both at some point create a map of Old->New
instructions and update dbg.value uses of these. They did this by
iterating over the dbg.value's location operands, and if an instance of
the old instruction was found, replaceVariableLocationOp would be
called on that dbg.value. This would cause an error if the same operand
appeared multiple times as a location operand, as the first call to
replaceVariableLocationOp would update all uses of the old instruction,
invalidating the old iterator and eventually hitting an assertion.
This has been fixed by no longer iterating over the dbg.value's location
operands directly, but by first collecting them into a set and then
iterating over that, ensuring that we never attempt to replace a
duplicated operand multiple times.
Differential Revision: https://reviews.llvm.org/D105129
This API is not compatible with opaque pointers, the method
accepting an explicit pointer element type should be used instead.
Thankfully there were few in-tree users. The BPF case still ends
up using the pointer element type for now and needs something like
D105407 to avoid doing so.
Same as other CreateLoad-style APIs, these need an explicit type
argument to support opaque pointers.
Differential Revision: https://reviews.llvm.org/D105395
This replaces the current ad-hoc implementation,
by syncing the code from InstCombine's implementation in `InstCombinerImpl::visitUnreachableInst()`,
with one exception that here in SimplifyCFG we are allowed to remove EH instructions.
Effectively, this now allows SimplifyCFG to remove calls (iff they won't throw and will return),
arithmetic/logic operations, etc.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D105374
D74751 added `ClearDSOLocalOnDeclarations` and dropped dso_local for
isDeclarationForLinker `GlobalValue`s. It missed a case for imported
declarations (`doImportAsDefinition` is false while `isPerformingImport` is
true). This can lead to a linker error for a default visibility symbol in
`ld.lld -shared`.
When `ClearDSOLocalOnDeclarations` is true, we check
`isPerformingImport() && !doImportAsDefinition(&GV)` along with
`GV.isDeclarationForLinker()`. The new condition checks an imported declaration.
This patch fixes a `LLVMPolly.so` link error using a trunk clang -DLLVM_ENABLE_LTO=Thin.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D104986
Mimics similar change for InstCombine:
ce192ced2b / D104602
All these uses are in blocks that aren't reachable from function's entry,
and said blocks are removed by SimplifyCFG itself,
so we can't really test this change.
This tries to bail out if the PHI is in a `catchswitch` BB in
InstCombine. A PHI cannot be combined into a non-PHI instruction if it
is in a `catchswitch` BB, because `catchswitch` BB cannot have any
non-PHI instruction other than `catchswitch` itself.
The given test case started crashing after D98058.
Reviewed By: lebedev.ri, rnk
Differential Revision: https://reviews.llvm.org/D105309
Somewhat related to D105338.
While it is up for discussion whether or not volatile store traps,
so far there has been no complaints that volatile load/cmpxchg/atomicrmw also may trap.
And even if simplifycfg currently concervatively believes that to be the case,
instcombine does not: https://godbolt.org/z/5vhv4K5b8
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D105343
In the original review D87149 it was mentioned that this approach was tried,
and it lead to infinite combine loops, but i'm not seeing anything like that now,
neither in the `check-llvm`, nor on some codebases i tried.
This is a recommit of d9d65527c2,
which i immediately reverted because i have messed up something
during branch switch, and 597ccc92ce
accidentally ended up being pushed, which was very much not the intention.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D105339
In the original review D87149 it was mentioned that this approach was tried,
and it lead to infinite combine loops, but i'm not seeing anything like that now,
neither in the `check-llvm`, nor on some codebases i tried.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D105339
The compiler should not ignore UndefValue when gathering the scalars,
otherwise the resulting code may be less defined than the original one.
Also, grouped scalars to insert them at first to reduce the analysis in
further passes.
Differential Revision: https://reviews.llvm.org/D105275
If the store address does not dominate the matrix multiply, try to hoist
address computation instructions without side-effects and/or memory
reads before the multiply, to allow fusion.
Reviewed By: thegameg
Differential Revision: https://reviews.llvm.org/D105193
With 'for' loop there is is a single place where 'Current' is adjusted. It helps to avoid copy paste and makes a bit easy to understand overall loop controll flow.
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D101044
Previously we used the vector type, but we're loading/storing
invididual elements so I think only element alignment should matter.
Noticed while looking at the code for something else so I don't
have a test case.
Differential Revision: https://reviews.llvm.org/D105220
We need the compiler generated variable to override the weak symbol of
the same name inside the profile runtime, but using LinkOnceODRLinkage
results in weak symbol being emitted which leads to an issue where the
linker might choose either of the weak symbols potentially disabling the
runtime counter relocation.
This change replaces the use of weak definition inside the runtime with
an external weak reference to address the issue. We also place the
compiler generated symbol inside a COMDAT group so dead definition can
be garbage collected by the linker.
Differential Revision: https://reviews.llvm.org/D105176
This follows up to D104665 (which added umulo handling alongside the existing uaddo case), and generalizes for the remaining overflow intrinsics.
I went to add analogous handling to LVI, and discovered that LVI already had a more general implementation. Instead, we can port was LVI does to instcombine. (For context, LVI uses makeExactNoWrapRegion to constrain the value 'x' in blocks reached after a branch on the condition `op.with.overflow(x, C).overflow`.)
Differential Revision: https://reviews.llvm.org/D104932
In lots of places we were calling setDebugLocFromInst and passing
in the same Builder member variable found in InnerLoopVectorizer.
I personally found this confusing so I've changed the interface
to take an Optional<IRBuilder<> *> and we can now pass in None
when we want to use the class member variable.
Differential Revision: https://reviews.llvm.org/D105100
Now we lack a benchmark to measure the performance change for each
commit.
Since coro elide is the main optimization in coroutine module, I wonder
it may be an estimation to count the number of elided coroutine in
private code bases.
e.g., for a certain commit, if we found that the number of elided goes
down, we could find it before the commit check-in.
Reviewed By: lxfind
Differential Revision: https://reviews.llvm.org/D105095
This is one sibling of the fold added with c7b658aeb5 .
(X + C2) <u C --> X >s ~C2 (if C == C2 + SMIN)
I'm still not sure how to describe it best, but we're
translating 2 constants from an unsigned range comparison
to signed because that eliminates the offset (add) op.
This could be extended to handle the more general (non-constant)
pattern too:
https://alive2.llvm.org/ce/z/K-fMBf
define i1 @src(i8 %a, i8 %c2) {
%t = add i8 %a, %c2
%c = add i8 %c2, 128 ; SMIN
%ov = icmp ult i8 %t, %c
ret i1 %ov
}
define i1 @tgt(i8 %a, i8 %c2) {
%not_c2 = xor i8 %c2, -1
%ov = icmp sgt i8 %a, %not_c2
ret i1 %ov
}
Relevant discussion can be found at: https://lists.llvm.org/pipermail/llvm-dev/2021-January/148197.html
In the existing design, An SCC that contains a coroutine will go through the folloing passes:
Inliner -> CoroSplitPass (fake) -> FunctionSimplificationPipeline -> Inliner -> CoroSplitPass (real) -> FunctionSimplificationPipeline
The first CoroSplitPass doesn't do anything other than putting the SCC back to the queue so that the entire pipeline can repeat.
As you can see, we run Inliner twice on the SCC consecutively without doing any real split, which is unnecessary and likely unintended.
What we really wanted is this:
Inliner -> FunctionSimplificationPipeline -> CoroSplitPass -> FunctionSimplificationPipeline
(note that we don't really need to run Inliner again on the ramp function after split).
Hence the way we do it here is to move CoroSplitPass to the end of the CGSCC pipeline, make it once for real, insert the newly generated SCCs (the clones) back to the pipeline so that they can be optimized, and also add a function simplification pipeline after CoroSplit to optimize the post-split ramp function.
This approach also conforms to how the new pass manager works instead of relying on an adhoc post split cleanup, making it ready for full switch to new pass manager eventually.
By looking at some of the changes to the tests, we can already observe that this changes allows for more optimizations applied to coroutines.
Reviewed By: aeubanks, ChuanqiXu
Differential Revision: https://reviews.llvm.org/D95807
There must be a better way to describe this pattern in words?
(X + C2) >u C --> X <s -C2 (if C == C2 + SMAX)
This could be extended to handle the more general (non-constant)
pattern too:
https://alive2.llvm.org/ce/z/rdfNFP
define i1 @src(i8 %a, i8 %c1) {
%t = add i8 %a, %c1
%c2 = add i8 %c1, 127 ; SMAX
%ov = icmp ugt i8 %t, %c2
ret i1 %ov
}
define i1 @tgt(i8 %a, i8 %c1) {
%neg_c1 = sub i8 0, %c1
%ov = icmp slt i8 %a, %neg_c1
ret i1 %ov
}
The pattern was noticed as a by-product of D104932.
We already implemented this for the select form, but the intrinsic form was missing. Note that this doesn't change poison behavior as 1 is non-poison, and the optimized form is still poison exactly when x is.
The remarks will trigger on some functions that are marked cold, such as the
`__muldc3` intrinsic functions. Change the remarks to avoid these functions.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D105196
This patch adds additional remarks, suggesting the use of `noescape` for failed
globalization and indicating when internalization failed.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D105150
Now the option is off by default. Since we are not sure if this option
would make the compile time increase aggressively. Although we tested it
on SPEC2017, we may need to test more to make it on by default.
Reviewed By: SjoerdMeijer
Differential Revision: https://reviews.llvm.org/D104365
Now we lack a benchmark to measure the performance change for each
commit.
Since coro elide is the main optimization in coroutine module, I wonder
it may be an estimation to count the number of elided coroutine in
private code bases.
e.g., for a certain commit, if we found that the number of elided goes
down, we could find it before the commit check-in.
Reviewed By: lxfind
Differential Revision: https://reviews.llvm.org/D105095
This allows application code checks if origin tracking is on before
printing out traces.
-dfsan-track-origins can be 0,1,2.
The current code only distinguishes 1 and 2 in compile time, but not at runtime.
Made runtime distinguish 1 and 2 too.
Reviewed By: browneee
Differential Revision: https://reviews.llvm.org/D105128
The code was previously relying on the fact that an incorrectly
typed global would result in the insertion of a BitCast constant
expression. With opaque pointers, this is no longer the case, so
we should check the type explicitly.
After SLP + LTO we may have have reduction(shuffle V, poison,
mask). This can be simplified to just reduction(V) if the mask is only
for single vector and just all elements from this vector are permuted,
without reusing, replacing with undefs and/or other values, etc.
Differential Revision: https://reviews.llvm.org/D105053
If we unroll a loop in the vectorizer (without vectorizing), and the cost model requires a epilogue be generated for correctness, the code generation must actually do so.
The included test case on an unmodified opt will access memory one past the expected bound. As a result, this patch is fixing a latent miscompile.
Differential Revision: https://reviews.llvm.org/D103700
While we might eventually want to disallow allocas that do not have the
alloca-AS set, it seems undesirable to crash on them. Add a cast when
required so that we can support such allocas (at least here).
Differential Revision: https://reviews.llvm.org/D104866
This patch fixes a crash when the target instruction for sinking is
dead. In that case, no recipe is created and trying to get the recipe
for it results in a crash. To ensure all sink targets are alive, find &
use the first previous alive instruction.
Note that the case where the sink source is dead is already handled.
Found by
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35320
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D104603
Previously in setCostBasedWideningDecision if we encountered an
invariant store we just assumed that we could scalarize the store
and called getUniformMemOpCost to get the associated cost.
However, for scalable vectors this is not an option because it is
not currently possibly to scalarize the store. At the moment we
crash in VPReplicateRecipe::execute when trying to scalarize the
store.
Therefore, I have changed setCostBasedWideningDecision so that if
we are storing a scalable vector out to a uniform address and the
target supports scatter instructions, then we should use those
instead.
Tests have been added here:
Transforms/LoopVectorize/AArch64/sve-inv-store.ll
Differential Revision: https://reviews.llvm.org/D104624
In all of these, the value must be an instruction for us to succeed anyway,
so change it to maybe hopefully make further changes more straight-forward.
We could use a bigger hammer and bail out on any constant
expression, but there's a regression test that appears to
validly do the transform (although it may not have been
intending to check that optimization).
Currently OpenMPOpt will only check if a function is a kernel before deciding not to internalize it. Any uncalled function that gets internalized will be trivially dead in the module so this is unnnecessary.
Depends on D102423
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D104890