[InstCombine] Infer nusw + nneg -> nuw for getelementptr (#111144)

If the gep is nusw (usually via inbounds) and the offset is
non-negative, we can infer nuw.

Proof: https://alive2.llvm.org/ce/z

[InstCombine] Infer nusw + nneg -> nuw for getelementptr (#111144)

If the gep is nusw (usually via inbounds) and the offset is
non-negative, we can infer nuw.

Proof: https://alive2.llvm.org/ce/z/ihztLy

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[LLVM][IR] Use splat syntax when printing Constant[Data]Vector. (#112548)

[InstCombine] Set `samesign` when converting signed predicates into unsigned (#112642)

Alive2: https://alive2.llvm.org/ce/z/6cqdt-

[InstCombine] Remove optional LoopInfo dependency

https://github.com/llvm/llvm-project/pull/106075 has removed the
last dependency on LoopInfo in InstCombine, so don't fetch the
analysis anymore and

[InstCombine] Remove optional LoopInfo dependency

https://github.com/llvm/llvm-project/pull/106075 has removed the
last dependency on LoopInfo in InstCombine, so don't fetch the
analysis anymore and remove the use-loop-info pass option.

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[InstCombine] Canonicalize constant GEPs to i8 source element type (#68882)

This patch canonicalizes getelementptr instructions with constant
indices to use the `i8` source element type. This makes

[InstCombine] Canonicalize constant GEPs to i8 source element type (#68882)

This patch canonicalizes getelementptr instructions with constant
indices to use the `i8` source element type. This makes it easier for
optimizations to recognize that two GEPs are identical, because they
don't need to see past many different ways to express the same offset.

This is a first step towards
https://discourse.llvm.org/t/rfc-replacing-getelementptr-with-ptradd/68699.
This is limited to constant GEPs only for now, as they have a clear
canonical form, while we're not yet sure how exactly to deal with
variable indices.

The test llvm/test/Transforms/PhaseOrdering/switch_with_geps.ll gives
two representative examples of the kind of optimization improvement we
expect from this change. In the first test SimplifyCFG can now realize
that all switch branches are actually the same. In the second test it
can convert it into simple arithmetic. These are representative of
common optimization failures we see in Rust.

Fixes https://github.com/llvm/llvm-project/issues/69841.

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[InstCombine] Don't reassociate GEPs for loop invariance

Since D146813, LICM will reassociate GEPs to expose hoisting
opportunities itself. Don't perform this transform in InstCombine,
where it is f

[InstCombine] Don't reassociate GEPs for loop invariance

Since D146813, LICM will reassociate GEPs to expose hoisting
opportunities itself. Don't perform this transform in InstCombine,
where it is fragile because it depends on an optional LoopInfo
analysis.

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[InstCombine] Convert tests to opaque pointers (NFC)

The two debuginfo tests go away because the relevant transforms
no longer occur in this form, e.g. the "cast of alloca" transform
just doesn't ex

[InstCombine] Convert tests to opaque pointers (NFC)

The two debuginfo tests go away because the relevant transforms
no longer occur in this form, e.g. the "cast of alloca" transform
just doesn't exist with opaque pointers.

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[InstCombine] Name instructions in test (NFC)

[InstCombine] create a pass options container and add "use-loop-info" argument

This is a cleanup/modernization patch requested in D144045 to make loop
analysis a proper optional parameter to the pas

[InstCombine] create a pass options container and add "use-loop-info" argument

This is a cleanup/modernization patch requested in D144045 to make loop
analysis a proper optional parameter to the pass rather than a
semi-arbitrary value inherited via the pass pipeline.

It's a bit more complicated than the recent patch I started copying from
(D143980) because InstCombine already has an option for MaxIterations
(added with D71145).

I debated just deleting that option, but it was used by a pair of existing
tests, so I put it into a struct (code largely copied from SimplifyCFG's
implementation) to make the code more flexible for future options
enhancements.

I didn't alter the pass manager invocations of InstCombine in this patch
because the patch was already getting big, but that will be a small
follow-up as noted with the TODO comment.

Differential Revision: https://reviews.llvm.org/D144199

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[AsmParser] Remove typed pointer auto-detection

IR is now always parsed in opaque pointer mode, unless
-opaque-pointers=0 is explicitly given. There is no automatic
detection of typed pointers anymo

[AsmParser] Remove typed pointer auto-detection

IR is now always parsed in opaque pointer mode, unless
-opaque-pointers=0 is explicitly given. There is no automatic
detection of typed pointers anymore.

The -opaque-pointers=0 option is added to any remaining IR tests
that haven't been migrated yet.

Differential Revision: https://reviews.llvm.org/D141912

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[NFC][1/n] Remove -enable-new-pm=0 flags from lit tests

This is the first patch in a series intended for removing flag
-enable-new-pm=0 from lit tests. This is part of a bigger
effort of completely

[NFC][1/n] Remove -enable-new-pm=0 flags from lit tests

This is the first patch in a series intended for removing flag
-enable-new-pm=0 from lit tests. This is part of a bigger
effort of completely removing legacy code related to legacy
pass manager in favor of currently default new pass manager.

In this patch flag has been removed only from tests where no significant
change has been required because checks has been duplicated for
both PMs.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D134150

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[InstCombine] Fix inbounds preservation when swapping GEPs (PR44206)

When reassociating GEPs, we can only keep inbounds if both original
GEPs were inbounds, and their offsets have the same sign. For

[InstCombine] Fix inbounds preservation when swapping GEPs (PR44206)

When reassociating GEPs, we can only keep inbounds if both original
GEPs were inbounds, and their offsets have the same sign. For the
sake of simplicity, I only handle the case where both offsets are
non-negative here.

It would probably be fine to just not preserve inbounds at all here,
but as I don't see a compile-time impact for adding the
isKnownNonNegative() calls I went with this more conservative
approach.

Fixes https://github.com/llvm/llvm-project/issues/44206.

Differential Revision: https://reviews.llvm.org/D126687

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[InstCombine] When swapping GEPs, only keep inbounds if both are

If only one of the GEPs is inbounds, then after swapping, there is
no guarantee that one of them will be inbounds as well
(see e.g. h

[InstCombine] When swapping GEPs, only keep inbounds if both are

If only one of the GEPs is inbounds, then after swapping, there is
no guarantee that one of them will be inbounds as well
(see e.g. https://alive2.llvm.org/ce/z/agaCnp).

This is only a partial fix, because even if both are inbounds, the
result is not necessarily inbounds (if the offsets have different
signs).

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[InstCombine] Always create new GEPs when swapping GEPs

As the long explanatory comment attests, performing the modification
in place is pretty tricky. Drop this unnecessary complexity and
always cr

[InstCombine] Always create new GEPs when swapping GEPs

As the long explanatory comment attests, performing the modification
in place is pretty tricky. Drop this unnecessary complexity and
always create new instructions.

This should be NFC-ish, but can probably cause difference due to
worklist order.

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[InstCombine] Add tests for inbounds handling in loop invariant GEP fold (NFC)

[IRBuilder] Add IsInBounds parameter to CreateGEP()

We commonly want to create either an inbounds or non-inbounds GEP
based on a boolean value, e.g. when preserving inbounds from
existing GEPs. Dire

[IRBuilder] Add IsInBounds parameter to CreateGEP()

We commonly want to create either an inbounds or non-inbounds GEP
based on a boolean value, e.g. when preserving inbounds from
existing GEPs. Directly accept such a boolean in the API, rather
than requiring a ternary between CreateGEP and CreateInBoundsGEP.

This change is not entirely NFC, because we now preserve an
inbounds flag in a constant expression edge-case in InstCombine.

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Revert rG1c9bec727ab5c53fa060560dc8d346a911142170 : [InstCombine] Fold (gep (oneuse(gep Ptr, Idx0)), Idx1) -> (gep Ptr, (add Idx0, Idx1)) (PR51069)

Reverted (manually due to merge conflicts) while r

Revert rG1c9bec727ab5c53fa060560dc8d346a911142170 : [InstCombine] Fold (gep (oneuse(gep Ptr, Idx0)), Idx1) -> (gep Ptr, (add Idx0, Idx1)) (PR51069)

Reverted (manually due to merge conflicts) while regressions reported on PR51540 are investigated

As noticed on D106352, after we've folded "(select C, (gep Ptr, Idx), Ptr) -> (gep Ptr, (select C, Idx, 0))" if the inner Ptr was also a (now one use) gep we could then merge the geps, using the sum of the indices instead.

I've limited this to basic 2-op geps - a more general case further down InstCombinerImpl.visitGetElementPtrInst doesn't have the one-use limitation but only creates the add if it can be created via SimplifyAddInst.

https://alive2.llvm.org/ce/z/f8pLfD (Thanks Roman!)

Differential Revision: https://reviews.llvm.org/D106450

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[InstCombine] Avoid folding GEPs across loop boundaries

Folding a GEP from outside to inside a loop will materialize an add where there wasn't an equivalent operation before. Check the containing lo

[InstCombine] Avoid folding GEPs across loop boundaries

Folding a GEP from outside to inside a loop will materialize an add where there wasn't an equivalent operation before. Check the containing loops before making this fold.

Reviewed By: lebedev.ri

Differential Revision: https://reviews.llvm.org/D107935

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[NFC][InstCombine] Add test for one-use one-index geps in different loops

[InstCombine] allow for constant-folding in GEP transform

This would crash the reduced test or as described in
https://llvm.org/PR51485
...because we can't mark a constant (-expression) with 'inboun

[InstCombine] allow for constant-folding in GEP transform

This would crash the reduced test or as described in
https://llvm.org/PR51485
...because we can't mark a constant (-expression) with 'inbounds'.

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[InstCombine] Fold (gep (oneuse(gep Ptr, Idx0)), Idx1) -> (gep Ptr, (add Idx0, Idx1)) (PR51069)

As noticed on D106352, after we've folded "(select C, (gep Ptr, Idx), Ptr) -> (gep Ptr, (select C, Idx

[InstCombine] Fold (gep (oneuse(gep Ptr, Idx0)), Idx1) -> (gep Ptr, (add Idx0, Idx1)) (PR51069)

As noticed on D106352, after we've folded "(select C, (gep Ptr, Idx), Ptr) -> (gep Ptr, (select C, Idx, 0))" if the inner Ptr was also a (now one use) gep we could then merge the geps, using the sum of the indices instead.

I've limited this to basic 2-op geps - a more general case further down InstCombinerImpl.visitGetElementPtrInst doesn't have the one-use limitation but only creates the add if it can be created via SimplifyAddInst.

https://alive2.llvm.org/ce/z/f8pLfD (Thanks Roman!)

Differential Revision: https://reviews.llvm.org/D106450

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[InstCombine] Fold `(X >>? C1) << C2` patterns to shift+bitmask (PR37872)

This is essentially finalizes a revert of rL155136,
because nowadays the situation has improved, SCEV can model
all these pa

[InstCombine] Fold `(X >>? C1) << C2` patterns to shift+bitmask (PR37872)

This is essentially finalizes a revert of rL155136,
because nowadays the situation has improved, SCEV can model
all these patterns well, and we canonicalize rotate-like patterns
into a funnel shift intrinsics in InstCombine.
So this should not cause any pessimization.

I've verified the canonicalize-{a,l}shr-shl-to-masking.ll transforms
with alive, which confirms that we can freely preserve exact-ness,
and no-wrap flags.

Profs:
* base: https://rise4fun.com/Alive/gPQ
* exact-ness preservation: https://rise4fun.com/Alive/izi
* nuw preservation: https://rise4fun.com/Alive/DmD
* nsw preservation: https://rise4fun.com/Alive/SLN6N
* nuw nsw preservation: https://rise4fun.com/Alive/Qp7

Refs. https://reviews.llvm.org/D46760

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[test][InstCombine][NewPM] Fix InstCombine tests under NPM

Some of these depended on analyses being present that aren't provided
automatically in NPM.

early_dce_clobbers_callgraph.ll was previously

[test][InstCombine][NewPM] Fix InstCombine tests under NPM

Some of these depended on analyses being present that aren't provided
automatically in NPM.

early_dce_clobbers_callgraph.ll was previously inlining a noinline function?

cast-call-combine.ll relied on the legacy always-inline pass being a
CGSCC pass and getting rerun.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D88187

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Revert "Temporarily Revert "Add basic loop fusion pass.""

The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552

[InstCombine] Properly change GEP type when reassociating loop invariant GEP chains

Summary:
This is a fix to PR37005.

Essentially, rL328539 ([InstCombine] reassociate loop invariant GEP chains to

[InstCombine] Properly change GEP type when reassociating loop invariant GEP chains

Summary:
This is a fix to PR37005.

Essentially, rL328539 ([InstCombine] reassociate loop invariant GEP chains to enable LICM) contains a bug
whereby it will convert:
%src = getelementptr inbounds i8, i8* %base, <2 x i64> %val
%res = getelementptr inbounds i8, <2 x i8*> %src, i64 %val2
into:
%src = getelementptr inbounds i8, i8* %base, i64 %val2
%res = getelementptr inbounds i8, <2 x i8*> %src, <2 x i64> %val

By swapping the index operands if the GEPs are in a loop, and %val is loop variant while %val2
is loop invariant.

This fix recreates new GEP instructions if the index operand swap would result in the type
of %src changing from vector to scalar, or vice versa.

Reviewers: sebpop, spatel

Reviewed By: sebpop

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45287

llvm-svn: 329331

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