When we simplify at least one operand in the Attributor simplification
we can use the InstSimplify to work on the simplified operands. This
allows us to avoid duplication of the logic.
Depends on D106189
Differential Revision: https://reviews.llvm.org/D106190
D106185 allows us to determine if a store is needed easily. Using that
knowledge we can start to delete dead stores.
In AAIsDead we now track more state as an instruction can be dead (= the
old optimisitc state) or just "removable". A store instruction can be
removable while being very much alive, e.g., if it stores a constant
into an alloca or internal global. If we would pretend it was dead
instead of only removablewe we would ignore it when we determine what
values a load can see, so that is not what we want.
Differential Revision: https://reviews.llvm.org/D106188
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
As a first step to simplify loads we only handle `null` and `undef`
underlying objects, as well as objects that have the load as a single user.
Loads of those values can be replaced by the initializer, if any.
Proper reasoning is introduced in a follow up patch
Differential Revision: https://reviews.llvm.org/D103862
Not all attributes are able to handle the interprocedural step and
follow the uses into a call site. Let them be able to combine call site
uses instead. This might result in some unused values/arguments being
leftover but it removes problems where we misused "is dead" even though
it was actually "is simplified/replaced".
We explicitly check for dead values due to constant propagation in
`AAIsDeadValueImpl::areAllUsesAssumedDead` instead.
Differential Revision: https://reviews.llvm.org/D103858
Broke check-clang, see https://reviews.llvm.org/D102307#2869065
Ran `git revert -n ebbe149a6f08535ede848a531a601ae6591cfbc5..269416d41908bb670f67af689155d5ab8eea689a`
Not all attributes are able to handle the interprocedural step and
follow the uses into a call site. Let them be able to combine call site
uses instead. This might result in some unused values/arguments being
leftover but it removes problems where we misused "is dead" even though
it was actually "is simplified/replaced".
We explicitly check for dead values due to constant propagation in
`AAIsDeadValueImpl::areAllUsesAssumedDead` instead.
Differential Revision: https://reviews.llvm.org/D103858
Since D86233 we have `mustprogress` which, in combination with
`readonly`, implies `willreturn`. The idea is that every side-effect
has to be modeled as a "write". Consequently, `readonly` means there
is no side-effect, and `mustprogress` guarantees that we cannot "loop"
forever without side-effect.
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D94125
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
This is a follow-up of D95238's LangRef update.
This patch updates `programUndefinedIfUndefOrPoison(V)` to return true if
`V` is used by any memory-accessing instruction.
Interestingly, this affected many tests in Attributors, mainly about adding noundefs.
The tests are updated using llvm/utils/update_test_checks.py. I checked that the diffs
are about updating noundefs.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D96642
Summary:
The module slice describes which functions we can analyze and transform
while working on an SCC as part of the Attributor-CGSCC pass. So far we
simply restricted it to the SCC.
Reviewers: jdoerfert
Differential Revision: https://reviews.llvm.org/D86319
This patch introduces a new abstract attribute `AANoUndef` which corresponds to `noundef` IR attribute and deduce them.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D85184
All these tests already explicitly test against both legacy PM and NPM.
$ sed -i 's/ -attributor / -attributor -enable-new-pm=0 /g' $(rg --path-separator // -l -- -passes=)
$ sed -i 's/ -attributor-cgscc / -attributor-cgscc -enable-new-pm=0 /g' $(rg --path-separator // -l -- -passes=)
Now all tests in Transforms/Attributor/ pass under NPM.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D84813
Summary:
All tests are updated, except wrapper.ll since it is not working nicely
with newly created functions.
Reviewers: jdoerfert, uenoku, baziotis, homerdin
Subscribers: arphaman, jfb, kuter, bbn, okura, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D84130
Attributor tests are mostly updated using the auto upgrade scripts but
sometimes we forget. If we do it manually or continue using old check
lines that still match we see unrelated changes down the line. This is
just a cleanup.
This patch introduces an improvement in the Alignment of the loads
generated in createReplacementValues() by querying AAAlign attribute for
the best Alignment for the base.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D76550
We should never give up on AAIsDead as it guards other AAs from
unreachable code (in which SSA properties are meaningless). We did
however use required dependences on some queries in AAIsDead which
caused us to invalidate AAIsDead if the queried AA got invalidated.
We now use optional dependences instead. The bug that exposed this is
added to the liveness.ll test and other test changes show the impact.
Bug report by @sdmitriev.
During an update of AAIsDead, new instructions become live. If we query
information from them, the result is often just the initial state, e.g.,
for call site `noreturn` and `nounwind`. We will now trigger an update
for cached attributes during the AAIsDead update, though other AAs might
later use the same API.
In a recent patch we introduced a problem with abstract attributes that
were assumed dead at some point. Since `Attributor::updateAA` was
introduced in 95e0d28b71, we did not
remember the dependence on the liveness AA when an abstract attribute
was assumed dead and therefore not updated.
Explicit reproducer added in liveness.ll.
---
Single run of the Attributor module and then CGSCC pass (oldPM)
for SPASS/clause.c (~10k LLVM-IR loc):
Before:
```
calls to allocation functions: 509242 (345483/s)
temporary memory allocations: 98666 (66937/s)
peak heap memory consumption: 18.60MB
peak RSS (including heaptrack overhead): 103.29MB
total memory leaked: 269.10KB
```
After:
```
calls to allocation functions: 529332 (355494/s)
temporary memory allocations: 102107 (68574/s)
peak heap memory consumption: 19.40MB
peak RSS (including heaptrack overhead): 102.79MB
total memory leaked: 269.10KB
```
Difference:
```
calls to allocation functions: 20090 (1339333/s)
temporary memory allocations: 3441 (229400/s)
peak heap memory consumption: 801.45KB
peak RSS (including heaptrack overhead): 0B
total memory leaked: 0B
```
When the Attributor was created the test update scripts were not well
suited to deal with the challenges of IR attribute checking. This
partially improved.
Since then we also added three additional configurations that need
testing; in total we now have the following four:
{ TUNIT, CGSCC } x { old pass manager (OPM), new pass manager (NPM) }
Finally, the number of developers and tests grew rapidly (partially due
to the addition of ArgumentPromotion and IPConstantProp tests), which
resulted in tests only being run in some configurations, different
prefixes being used, and different "styles" of checks being used.
Due to the above reasons I believed we needed to take another look at
the test update scripts. While we started to use them, via UTC_ARGS:
--enable/disable, the other problems remained. To improve the testing
situation for *all* configurations, to simplify future updates to the
test, and to help identify subtle effects of future changes, we now use
the test update scripts for (almost) all Attributor tests.
An exhaustive prefix list minimizes the number of check lines and makes
it easy to identify and compare configurations.
Tests have been adjusted in the process but we tried to keep their
intend unchanged.
Reviewed By: sstefan1
Differential Revision: https://reviews.llvm.org/D76588
When the Attributor was created the test update scripts were not well
suited to deal with the challenges of IR attribute checking. This
partially improved.
Since then we also added three additional configurations that need
testing; in total we now have the following four:
{ TUNIT, CGSCC } x { old pass manager (OPM), new pass manager (NPM) }
Finally, the number of developers and tests grew rapidly (partially due
to the addition of ArgumentPromotion and IPConstantProp tests), which
resulted in tests only being run in some configurations, different
prefixes being used, and different "styles" of checks being used.
Due to the above reasons I believed we needed to take another look at
the test update scripts. While we started to use them, via UTC_ARGS:
--enable/disable, the other problems remained. To improve the testing
situation for *all* configurations, to simplify future updates to the
test, and to help identify subtle effects of future changes, we now use
the test update scripts for (almost) all Attributor tests.
An exhaustive prefix list minimizes the number of check lines and makes
it easy to identify and compare configurations.
Tests have been adjusted in the process but we tried to keep their
intend unchanged.
Reviewed By: sstefan1
Differential Revision: https://reviews.llvm.org/D76588
Query AAValueSimplify on pointers in memory accessing instructions to take
advantage of the constant propagation (or any other value simplification) of such values.
We used coarse-grained liveness before, thus we looked if the
instruction was executed, but we did not use fine-grained liveness,
hence if the instruction was needed or could be deleted even if the
surrounding ones are live. This patches introduces this level of
liveness checks together with other liveness queries, e.g., for uses.
For more control we enforce that all liveness queries go through the
Attributor.
Test have been adjusted to reflect the changes or augmented to prevent
deletion of the parts we want to check.
Reviewed By: sstefan1
Differential Revision: https://reviews.llvm.org/D73313
In addition to the module pass, this patch introduces a CGSCC pass that
runs the Attributor on a strongly connected component of the call graph
(both old and new PM). The Attributor was always design to be used on a
subset of functions which makes this patch mostly mechanical.
The one change is that we give up `norecurse` deduction in the module
pass in favor of doing it during the CGSCC pass. This makes the
interfaces simpler but can be revisited if needed.
Reviewed By: hfinkel
Differential Revision: https://reviews.llvm.org/D70767
If all call sites are in `norecurse` functions we can derive `norecurse`
as the ReversePostOrderFunctionAttrsPass does. This should make
ReversePostOrderFunctionAttrsLegacyPass obsolete once the Attributor is
enabled.
Reviewed By: uenoku
Differential Revision: https://reviews.llvm.org/D72017
A pointer is privatizeable if it can be replaced by a new, private one.
Privatizing pointer reduces the use count, interaction between unrelated
code parts. This is a first step towards replacing argument promotion.
While we can already handle recursion (unlike argument promotion!) we
are restricted to stack allocations for now because we do not analyze
the uses in the callee.
Reviewed By: uenoku
Differential Revision: https://reviews.llvm.org/D68852
This patch modularizes the way we check for no-alias call site arguments
by putting the existing logic into helper functions. The reasoning was
not changed but special cases for readonly/readnone were added.
Summary:
This patch moves the test cases related to Attributor to `Transforms/Attributor` folder.
We have used `Transforms/FunctionAttrs` as the primary folder for Attributor test but we need to change testing way now.
For the test cases which I think functionattrs doesn't infer anything something like (willreturn, nosync, value-simplify, h2s ..etc), I moved them with the command `git mv`.
For the test cases in which functoinattrs and attributor are tested, I copied the test to the folder and remove the check only used by functoinattrs.
Reviewers: jdoerfert, sstefan1
Reviewed By: jdoerfert
Subscribers: jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70843
Johannes Doerfert