[IR] Convert from nocapture to captures(none) (#123181)

This PR removes the old `nocapture` attribute, replacing it with the new
`captures` attribute introduced in #116990. This change is
intended

[IR] Convert from nocapture to captures(none) (#123181)

This PR removes the old `nocapture` attribute, replacing it with the new
`captures` attribute introduced in #116990. This change is
intended to be essentially NFC, replacing existing uses of `nocapture`
with `captures(none)` without adding any new analysis capabilities.
Making use of non-`none` values is left for a followup.

Some notes:
* `nocapture` will be upgraded to `captures(none)` by the bitcode
reader.
* `nocapture` will also be upgraded by the textual IR reader. This is to
make it easier to use old IR files and somewhat reduce the test churn in
this PR.
* Helper APIs like `doesNotCapture()` will check for `captures(none)`.
* MLIR import will convert `captures(none)` into an `llvm.nocapture`
attribute. The representation in the LLVM IR dialect should be updated
separately.

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[Attributor] Don't construct pretty GEPs

Bring this in line with other transforms like ArgPromotion/SROA/
SCEVExpander and always produce canonical i8 GEPs.

[Attributor] Try to remove argmem effects after signature rewrite

If the new signature has only readnone pointers we can remove any argmem
effect from the function signature.

[Attributor] Allow IR-attr deduction for non-IPO amendable functions

If the function is non-IPO amendable we do skip most attributes/AAs.
However, if an AA has a isImpliedByIR that can deduce the at

[Attributor] Allow IR-attr deduction for non-IPO amendable functions

If the function is non-IPO amendable we do skip most attributes/AAs.
However, if an AA has a isImpliedByIR that can deduce the attribute from
other attributes, we can run those. For now, we manually enable them,
if we have more later we can use some automation/flag.

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[Attributor] Remove the iteration count verification

It was never really useful to track #iterations, though it helped during
the initial development. What we should track, in a follow up, are
poten

[Attributor] Remove the iteration count verification

It was never really useful to track #iterations, though it helped during
the initial development. What we should track, in a follow up, are
potentially #updates. That is also what we should restrict instead of
the #iterations.

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[Attributor][OpenMP][NFC] Cleanup tests via update script

[Attributor] Convert some tests to opaque pointers (NFC)

These were converted without adjustments.

[Attribute] Clean up test prefixes (NFC)

Now that the legacy PM is no longer tested, the huge matrix of
test prefixes used by attributor tests is no longer needed and very
confusing for the casual r

[Attribute] Clean up test prefixes (NFC)

Now that the legacy PM is no longer tested, the huge matrix of
test prefixes used by attributor tests is no longer needed and very
confusing for the casual reader. Reduce the prefixes down to just
CHECK, TUNIT and CGSCC.

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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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[Attributor] Replace AAValueSimplify with AAPotentialValues

For the longest time we used `AAValueSimplify` and
`genericValueTraversal` to determine "potential values". This was
problematic for many

[Attributor] Replace AAValueSimplify with AAPotentialValues

For the longest time we used `AAValueSimplify` and
`genericValueTraversal` to determine "potential values". This was
problematic for many reasons:
- We recomputed the result a lot as there was no caching for the 9
locations calling `genericValueTraversal`.
- We added the idea of "intra" vs. "inter" procedural simplification
only as an afterthought. `genericValueTraversal` did offer an option
but `AAValueSimplify` did not. Thus, we might end up with "too much"
simplification in certain situations and then gave up on it.
- Because `genericValueTraversal` was not a real `AA` we ended up with
problems like the infinite recursion bug (#54981) as well as code
duplication.

This patch introduces `AAPotentialValues` and replaces the
`AAValueSimplify` uses with it. `genericValueTraversal` is folded into
`AAPotentialValues` as are the instruction simplifications performed in
`AAValueSimplify` before. We further distinguish "intra" and "inter"
procedural simplification now.

`AAValueSimplify` was not deleted as we haven't ported the
re-materialization of instructions yet. There are other differences over
the former handling, e.g., we may not fold trivially foldable
instructions right now, e.g., `add i32 1, 1` is not folded to `i32 2`
but if an operand would be simplified to `i32 1` we would fold it still.

We are also even more aware of function/SCC boundaries in CGSCC passes,
which is good even if some tests look like they regress.

Fixes: https://github.com/llvm/llvm-project/issues/54981

Note: A previous version was flawed and consequently reverted in
6555558a80589d1c5a1154b92cc3af9495f8f86c.

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Revert "[Attributor] Replace AAValueSimplify with AAPotentialValues"

This reverts commit f17639ea0cd30f52ac853ba2eb25518426cc3bb8 as three
AMDGPU tests haven't been updated. Will need to verify the

Revert "[Attributor] Replace AAValueSimplify with AAPotentialValues"

This reverts commit f17639ea0cd30f52ac853ba2eb25518426cc3bb8 as three
AMDGPU tests haven't been updated. Will need to verify the changes are
not regressions we should avoid.

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[Attributor] Replace AAValueSimplify with AAPotentialValues

For the longest time we used `AAValueSimplify` and
`genericValueTraversal` to determine "potential values". This was
problematic for many

[Attributor] Replace AAValueSimplify with AAPotentialValues

For the longest time we used `AAValueSimplify` and
`genericValueTraversal` to determine "potential values". This was
problematic for many reasons:
- We recomputed the result a lot as there was no caching for the 9
locations calling `genericValueTraversal`.
- We added the idea of "intra" vs. "inter" procedural simplification
only as an afterthought. `genericValueTraversal` did offer an option
but `AAValueSimplify` did not. Thus, we might end up with "too much"
simplification in certain situations and then gave up on it.
- Because `genericValueTraversal` was not a real `AA` we ended up with
problems like the infinite recursion bug (#54981) as well as code
duplication.

This patch introduces `AAPotentialValues` and replaces the
`AAValueSimplify` uses with it. `genericValueTraversal` is folded into
`AAPotentialValues` as are the instruction simplifications performed in
`AAValueSimplify` before. We further distinguish "intra" and "inter"
procedural simplification now.

`AAValueSimplify` was not deleted as we haven't ported the
re-materialization of instructions yet. There are other differences over
the former handling, e.g., we may not fold trivially foldable
instructions right now, e.g., `add i32 1, 1` is not folded to `i32 2`
but if an operand would be simplified to `i32 1` we would fold it still.

We are also even more aware of function/SCC boundaries in CGSCC passes,
which is good even if some tests look like they regress.

Fixes: https://github.com/llvm/llvm-project/issues/54981

Note: A previous version was flawed and consequently reverted in
6555558a80589d1c5a1154b92cc3af9495f8f86c.

show more ...

Revert "[Attributor] Replace AAValueSimplify with AAPotentialValues"

This reverts commit da50dab1ae111e9e6cb0248a47a038b17f798705.

Patch broke AMD GPU OpenMP offload buildbots.
https://lab.llvm.org

Revert "[Attributor] Replace AAValueSimplify with AAPotentialValues"

This reverts commit da50dab1ae111e9e6cb0248a47a038b17f798705.

Patch broke AMD GPU OpenMP offload buildbots.
https://lab.llvm.org/buildbot/#/builders/193/builds/13246

show more ...

[Attributor] Replace AAValueSimplify with AAPotentialValues

For the longest time we used `AAValueSimplify` and
`genericValueTraversal` to determine "potential values". This was
problematic for many

[Attributor] Replace AAValueSimplify with AAPotentialValues

For the longest time we used `AAValueSimplify` and
`genericValueTraversal` to determine "potential values". This was
problematic for many reasons:
- We recomputed the result a lot as there was no caching for the 9
locations calling `genericValueTraversal`.
- We added the idea of "intra" vs. "inter" procedural simplification
only as an afterthought. `genericValueTraversal` did offer an option
but `AAValueSimplify` did not. Thus, we might end up with "too much"
simplification in certain situations and then gave up on it.
- Because `genericValueTraversal` was not a real `AA` we ended up with
problems like the infinite recursion bug (#54981) as well as code
duplication.

This patch introduces `AAPotentialValues` and replaces the
`AAValueSimplify` uses with it. `genericValueTraversal` is folded into
`AAPotentialValues` as are the instruction simplifications performed in
`AAValueSimplify` before. We further distinguish "intra" and "inter"
procedural simplification now.

`AAValueSimplify` was not deleted as we haven't ported the
re-materialization of instructions yet. There are other differences over
the former handling, e.g., we may not fold trivially foldable
instructions right now, e.g., `add i32 1, 1` is not folded to `i32 2`
but if an operand would be simplified to `i32 1` we would fold it still.

We are also even more aware of function/SCC boundaries in CGSCC passes,
which is good.

Fixes: https://github.com/llvm/llvm-project/issues/54981

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Revert "[Attributor] CGSCC pass should not recompute results outside the SCC"

This reverts commit 0d7f81e31315f8cda56ce6fde5ff5145e0325c51, it caused
the AMDGPU tests that use the Attributor to fail.

[Attributor] CGSCC pass should not recompute results outside the SCC

When we run the CGSCC pass we should only invest time on the SCC. We can
initialize AAs with information from the module slice bu

[Attributor] CGSCC pass should not recompute results outside the SCC

When we run the CGSCC pass we should only invest time on the SCC. We can
initialize AAs with information from the module slice but we should not
update those AAs.

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[Attributor] Cleanup manifest and liveness for CGSCC passes

There was some ad-hoc handling of liveness and manifest to avoid
breaking CGSCC guarantees. Things always slipped through though.
This cle

[Attributor] Cleanup manifest and liveness for CGSCC passes

There was some ad-hoc handling of liveness and manifest to avoid
breaking CGSCC guarantees. Things always slipped through though.
This cleanup will:

1) Prevent us from manifesting any "information" outside the CGSCC.
This might be too conservative but we need to opt-in to annotation
not try to avoid some problematic ones.
2) Avoid running any liveness analysis outside the CGSCC. We did have
some AAIsDeadFunction handling to this end but we need this for all
AAIsDead classes. The reason is that AAIsDead information is only
correct if we actually manifest it, since we don't (see point 1) we
cannot actually derive/use it at all. We are currently trying to
avoid running any AA updates outside the CGSCC but that seems to
impact things quite a bit.
3) Assert, don't check, that our modifications (during cleanup) modifies
only CGSCC functions.

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[Attributor] Make interprocedural value explicit in genericValueTraversal

genericValueTraversal can look through arguments and allow value
simplification across function boundaries. In fact, the lat

[Attributor] Make interprocedural value explicit in genericValueTraversal

genericValueTraversal can look through arguments and allow value
simplification across function boundaries. In fact, the latter already
happened unchecked. With this change we allow the user of
genericValueTraversal to opt-out of interprocedural traversal if
required. We explicitly look through arguments now which helps to do
various things, incl. the propagation of constants into OpenMP parallel
regions (on the host).

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[Attributor][FIX] Liveness handling in the isAssumedDead helpers

This fixes a conceptual problem with our AAIsDead usage which conflated
call site liveness with call site return value liveness. With

[Attributor][FIX] Liveness handling in the isAssumedDead helpers

This fixes a conceptual problem with our AAIsDead usage which conflated
call site liveness with call site return value liveness. Without the
fix tests would obviously miscompile as we make genericValueTraversal
more powerful (in a follow up). The effects on the tests are mixed but
mostly marginal. The most prominent one is the lack of `noreturn` for
functions. The reason is that we make entire blocks live at the same
time (for time reasons). Now that we actually look at the block
liveness, which we need to do, the return instructions are live and
will survive. As an example, `noreturn_async.ll` has been modified
to retain the `noreturn` even with block granularity. We could address
this easily but there is little need in practice.

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[Attributor] Generalize GEP construction

Make use of the getGEPIndicesForOffset() helper for creating GEPs.
This handles arrays as well, uses correct GEP index types and
reduces code duplication.

D

[Attributor] Generalize GEP construction

Make use of the getGEPIndicesForOffset() helper for creating GEPs.
This handles arrays as well, uses correct GEP index types and
reduces code duplication.

Differential Revision: https://reviews.llvm.org/D112263

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[Attributor] Introduce AAPointerInfo

This patch introduces AAPointerInfo which tracks the uses of a pointer
and places them in "bins" based on their offset from the base and access
size.

As with ot

[Attributor] Introduce AAPointerInfo

This patch introduces AAPointerInfo which tracks the uses of a pointer
and places them in "bins" based on their offset from the base and access
size.

As with other AAs, any pointer can be tracked but it is up to the user
to make sense of the results. The user in this patch is AAValueSimplify
and AAPotentialValues which both utilize AAPointerInfo to determine the
value of a load. For now, this is restricted to loads of allocas and
internal globals. Through the use of AAPointerInfo and the "bins" we can
track struct members separately. The users also know that storing only
zeros (at unknown indices) will result in loading only 0 (from unknown
indices). Other than that, the users are flow and context insensitive
(for now).

To deal with the "bins" more easily, AAPointerInfo provides a
forallInterfearingAccesses that applies a callback on all accesses
that might interfere with a given load or store.

Differential Revision: https://reviews.llvm.org/D104432

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[Attributor][NFC] Update tests after D94741

The update_test_checks script can now check for global symbols and is able
to handle them properly when they differ across prefixes, e.g.,
attribute #0 mi

[Attributor][NFC] Update tests after D94741

The update_test_checks script can now check for global symbols and is able
to handle them properly when they differ across prefixes, e.g.,
attribute #0 might be different in different runs.

This patch simply updates all the Attributor tests with the new script.

Reviewed By: sstefan1

Differential Revision: https://reviews.llvm.org/D97906

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[Attributor][FIX] Properly promote arguments pointers to arrays

When we promote pointer arguments we did compute a wrong offset and use
a wrong type for the array case.

Bug reported and reduced by

[Attributor][FIX] Properly promote arguments pointers to arrays

When we promote pointer arguments we did compute a wrong offset and use
a wrong type for the array case.

Bug reported and reduced by Whitney Tsang <whitneyt@ca.ibm.com>.

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