The GPUDivergenceAnalysis is now renamed to just "DivergenceAnalysis"
since there is no conflict with LegacyDivergenceAnalysis. In the
legacy PM, this analysis can only be used through the legacy DA
serving as a wrapper. It is now made available as a pass in the new
PM, and has no relation with the legacy DA.
The new DA currently cannot handle irreducible control flow; its
presence can cause the analysis to run indefinitely. The analysis is
now modified to detect this and report all instructions in the
function as divergent. This is super conservative, but allows the
analysis to be used without hanging the compiler.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D96615
This adds basic MVE costs for SMIN/SMAX/UMIN/UMAX, as well as MINNUM and
MAXNUM representing fmin and fmax. It tightens up the costs, not using a
ICmp+Select cost.
Differential Revision: https://reviews.llvm.org/D96603
This patch uses the function getShuffleCost with SK_Reverse to compute the cost
for experimental.vector.reverse.
For scalable vector type, it adds a table will the legal types on
AArch64TTIImpl::getShuffleCost to not assert in BasicTTIImpl::getShuffleCost,
and for fixed vector, it relies on the existing cost model in BasicTTIImpl.
Depends on D94883
Differential Revision: https://reviews.llvm.org/D95603
At this point, we can treat the case of GEP/GEP aliasing and
GEP/non-GEP aliasing in essentially the same way. The only
differences are that we need to do an additional negative GEP base
check, and that we perform a bailout on unknown sizes for the
GEP/non-GEP case (the latter exists only to limit compile-time).
This change is not quite NFC due to the peculiar effect that
the DecomposedGEP for V2 can actually be non-trivial even if V2
is not a GEP. The reason for this is that getUnderlyingObject()
can look through LCSSA phi nodes, while stripPointerCasts() doesn't.
This can lead to slightly better results if single-entry phi nodes
occur inside a loop, where looking through the phi node via aliasPhi()
would subject it to phi cycle equivalence restrictions. It would
probably make sense to adjust pointer cast stripping (for AA) to
handle this case, and ensure consistent results.
Instcombine will convert the nonnull and alignment assumption that use the boolean condtion
to an assumption that uses the operand bundles when knowledge retention is enabled.
Differential Revision: https://reviews.llvm.org/D82703
This fixes an overly restrictive assumption that the vector is a FixedVectorType,
in code that tries to calculate the cost of a cast operation when splitting
a too-wide vector. The algorithm works the same for scalable vectors, so this
patch removes the cast<FixedVectorType>.
Reviewed By: david-arm
Differential Revision: https://reviews.llvm.org/D96253
COST(zext (<4 x i32> load(...) to <4 x i64>)) != 0 when
<4 x i64> is an illegal result type that requires splitting
of the operation.
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D96250
The motivation for this is that I'm looking at an example that uses shifts as induction variables. There's lots of other omissions, but one of the first I noticed is that we can't compute tight known bits. (This indirectly causes SCEV's range analysis to produce very poor results as well.)
Differential Revision: https://reviews.llvm.org/D96440
This reverts commit b7d870eae7fdadcf10d0f177faa7409c2e37d776 and the
subsequent fix "[Polly] Fix build after AssumptionCache change (D96168)"
(commit e6810cab09fcbc87b6e5e4d226de0810e2f2ea38).
It caused indeterminism in the output, such that e.g. the
polly-x86_64-linux buildbot failed accasionally.
This adds the CostKind to getMVEVectorCostFactor, so that it can
automatically account for CodeSize costs, where it returns a cost of 1
not the MVEFactor used for Throughput/Latency. This helps simplify the
caller code and allows us to get the codesize cost more correct in more
cases.
Instcombine will convert the nonnull and alignment assumption that use the boolean condtion
to an assumption that uses the operand bundles when knowledge retention is enabled.
Differential Revision: https://reviews.llvm.org/D82703
When doing some recent debugging of the IROutliner, and using the similarity pass for debugging, just having the basic block and function isn't really enough to get all the information. This adds the first and last instruction to the output of the IRSimilarityPrinting pass to give better information to a user.
Reviewer: paquette
Differential Revision: https://reviews.llvm.org/D94304
PR49043 exposed a problem when it comes to RAUW llvm.assumes. While
D96106 would fix it for GVNSink, it seems a more general concern. To
avoid future problems this patch moves away from the vector of weak
reference model used in the assumption cache. Instead, we track the
llvm.assume calls with a callback handle which will remove itself from
the cache if the call is deleted.
Fixes PR49043.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D96168
MemorySSA currently treats lifetime.end intrinsics as not aliasing
anything. This breaks MemorySSA-based MemCpyOpt, because we'll happily
move a read of a pointer below a lifetime.end intrinsic, as no clobber
is reported.
I think the MemorySSA modelling here isn't correct: lifetime.end(p)
has approximately the same effect as doing a memcpy(p, undef), and
should be treated as a clobber.
This patch removes the special handling of lifetime.end, leaving
alias analysis to handle it appropriately.
Differential Revision: https://reviews.llvm.org/D95763
This patch adds a cost model for SK_Broadcast in
AArch64TTIImpl::getShuffleCost with scalable vector.
Without this patch, the scalable vector type relies on BasicTTIImpl cost
implementation and assert.
Differential Revision: https://reviews.llvm.org/D95598
Extend applyLoopGuards() to take into account conditions/assumes proving some
value %v to be divisible by D by rewriting %v to (%v / D) * D. This lets the
loop unroller and the loop vectorizer identify more loops as not requiring
remainder loops.
Differential Revision: https://reviews.llvm.org/D95521
In computeLoadConstantCompareExitLimit, the addrec used to compute the
exit count should be from the loop which the exiting block belongs to.
Reviewed by: mkazantsev
Differential Revision: https://reviews.llvm.org/D92367
This adds sadd.sat, uadd.sat, ssub.sat and usub.sat costs for AArch64,
similar to how they were recently added for ARM.
Differential Revision: https://reviews.llvm.org/D95292
I have removed an unnecessary assert in LoopVectorizationCostModel::getInstructionCost
that prevented a cost being calculated for select instructions when using
scalable vectors. In addition, I have changed AArch64TTIImpl::getCmpSelInstrCost
to only do special cost calculations for fixed width vectors and fall
back to the base version for scalable vectors.
I have added a simple cost model test for cmps and selects:
test/Analysis/CostModel/sve-cmpsel.ll
and some simple tests that show we vectorize loops with cmp and select:
test/Transforms/LoopVectorize/AArch64/sve-basic-vec.ll
Differential Revision: https://reviews.llvm.org/D95039
We tend to assume that the AA pipeline is by default the default AA
pipeline and it's confusing when it's empty instead.
PR48779
Initially reverted due to BasicAA running analyses in an unspecified
order (multiple function calls as parameters), fixed by fetching
analyses before the call to construct BasicAA.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D95117
This patch sets the default for llvm tests, with the exception of tests
under Reduce, because quite a few of them use 'FileCheck' as parameter
to a tool, and including a flag as that parameter would complicate
matters.
The rest of the patch undo-es the lit.local.cfg changes we progressively
introduced as temporary measure to avoid regressions under various
directories.
Differential Revision: https://reviews.llvm.org/D95111
We tend to assume that the AA pipeline is by default the default AA
pipeline and it's confusing when it's empty instead.
PR48779
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D95117
If a function doesn't contain loops and does not call non-willreturn
functions, then it is willreturn. Loops are detected by checking
for backedges in the function. We don't attempt to handle finite
loops at this point.
Differential Revision: https://reviews.llvm.org/D94633
This patch pre-commits a test case with wrong exit count
analysis for D92367.
Reviewed by: mkazantsev
Differential Revision: https://reviews.llvm.org/D94657
Currently LLVM is relying on ValueTracking's `isKnownNonZero` to attach `nonnull`, which can return true when the value is poison.
To make the semantics of `nonnull` consistent with the behavior of `isKnownNonZero`, this makes the semantics of `nonnull` to accept poison, and return poison if the input pointer isn't null.
This makes many transformations like below legal:
```
%p = gep inbounds %x, 1 ; % p is non-null pointer or poison
call void @f(%p) ; instcombine converts this to call void @f(nonnull %p)
```
Instead, this semantics makes propagation of `nonnull` to caller illegal.
The reason is that, passing poison to `nonnull` does not immediately raise UB anymore, so such program is still well defined, if the callee does not use the argument.
Having `noundef` attribute there re-allows this.
```
define void @f(i8* %p) { ; functionattr cannot mark %p nonnull here anymore
call void @g(i8* nonnull %p) ; .. because @g never raises UB if it never uses %p.
ret void
}
```
Another attribute that needs to be updated is `align`. This patch updates the semantics of align to accept poison as well.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D90529
Just like llvm.assume, there are a lot of cases where we can just ignore llvm.experimental.noalias.scope.decl.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D93042
We have no lowering for VSELECT vXi1, vXi1, vXi1, so mark them as
expanded to turn them into a series of logical operations.
Differential Revision: https://reviews.llvm.org/D94946
This adds some basic MVE sadd_sat/ssub_sat/uadd_sat/usub_sat costs,
based on when the instruction is legal. With smaller than legal types
that are promoted we generate shr(qadd(shl, shl)), so the cost is 4
appropriately.
Differential Revision: https://reviews.llvm.org/D94958
This patch computes the cost for vector.reduce<operand> for scalable vectors.
The cost is split into two parts: the legalization cost and the horizontal
reduction.
Differential Revision: https://reviews.llvm.org/D93639
We did not have specific costs for larger than legal truncates that were
not otherwise cheap (where they were next to stores, for example). As
MVE does not have a dedicated instruction for them (and we do not use
loads/stores yet), they should be expensive as they get expanded to a
series of lane moves.
Differential Revision: https://reviews.llvm.org/D94260
